COATING APPARATUS

A coating apparatus, which coats only the outer circumferential edge face of a workpiece with film-forming liquid, even if the workpiece is a non-circular thin lens or the like, a rotating mechanism is configured so that a workpiece and an imitating form having the same shape as the outer shape of the workpiece can rotate synchronously around the same rotation axis center, a coating mechanism includes a pressing roller that can rotate with the imitating form while being pressed against an outer circumferential edge face of the imitating form, and a coating part including a coating roller which, while being pressed against the outer circumferential edge face of the workpiece, rotates with the workpiece and applies the film forming liquid to the outer circumferential edge face of the workpiece, a rotary transmission unit that synchronously rotates the pressing roller and the coating roller having the same outer shape.

TECHNICAL FIELD

The present invention relates to a coating apparatus, and more particularly, to a coating apparatus which is able to coat the outer circumferential edge face of a workpiece of various shapes, such as a noncircular lens, with film-forming liquid.

BACKGROUND ART

The manufacturing process of optical instruments such as cameras and microscopes include the application of antireflection paint (e.g., black paint) to the periphery of the lens to prevent phenomena such as flare and ghosting that occur when incident light on the lens used in these optical instruments is reflected on the lens surface or outer lens surface. This coating process is also known as the black-coating process.

Since lenses used for the optical instruments come in various sizes and shapes, automation of the black-coating process is not easy. In addition, since the black-coating process requires high application precision, it is often applied manually by skilled workers using instruments such as brushes, making it difficult to improve work efficiency.

In view of these issues, coating apparatus for improving the efficiency of the coating process are disclosed, for example, in the following Patent Document 1 and 2.

The coating apparatus described in Patent Document 1 is configured to apply a coating material such as black ink to the periphery of a disc-shaped roll, transfer the coating material applied to the roll to the periphery of a disc-shaped transfer roll, and then apply the coating material transferred to the transfer roll to the periphery of a lens.

However, the roll transfer coating system described in Patent Document 1 cannot apply said coating material to optical elements that are not circular in shape, such as elliptic-format lenses, in a single process to the entire periphery.

In order to solve this problem, in the coating apparatus described in Patent Document 2, a cam of the same shape as the outer shape of the elliptic-format lens is fixed to the suction cylinder that holds the elliptic-format lens, a coating tip made of porous material is provided at the periphery of the elliptic-format lens, and a cam follower is provided at a position in contact with the cam. The cam follower is mounted on a lower slide table pressed by a lower spring via a cam base, and an upper slide table pressed by an upper spring is provided above the lower slide table, and the coating tip is mounted on the upper slide table via a tip holder.

According to the coating apparatus described in Patent Document 2, the cam, cam follower, lower slide table, and lower spring can adjust the distance from the coating tip to the lens coating surface in synchronization with the rotation of the elliptic-format lens, thereby automating the coating process for the periphery surface of the non-circular elliptic-format lens.

Problems to be Solved by the Invention

In recent years, in addition to the optical lenses for cameras and microscopes mentioned above, there has been a demand for the development of apparatus that can precisely apply light-shielding material to the outer circumferential edge face of non-circular thin lenses such as so-called smart glasses (glasses-type wearable devices), which display various information on the lens portion.

For example, assuming that the coating apparatus described in Patent Document 2 is used to apply the light-shielding material to the outer circumferential edge face of the thin lens, the coating apparatus described in Patent Document 2 will apply the light-shielding material by pressing the coating tip made of porous material against the outer circumferential edge face of the thin lens.

When using the coating apparatus described in Patent Document 2, the coating tip made of porous material is pressed against the outer circumferential edge face of the thin lens, so that the light-shielding material is applied not only to the outer circumferential edge face of the thin lens but also to the outer circumferential edge part, making it impossible to accurately apply said light-shielding material only to the outer circumferential edge face of the thin lens, in other words, with a coating width less than the thickness of the lens.

PRIOR ART DOCUMENT

Patent Document

SUMMARY OF THE INVENTION

Solution to Problem and Advantageous Effect of Invention

The present invention was developed in order to solve the above problem, and it is an object of the present invention to provide a coating apparatus, which make it possible to precisely coat only the outer circumferential edge face of a workpiece with film-forming liquid according to the outer shape of the workpiece, even if the workpiece is a non-circular thin lens or the like.

In order to achieve the above object, a coating apparatus according to a first aspect of the present invention is characterized by comprising a rotating mechanism that rotates a workpiece and a coating mechanism that applies the film-forming liquid to the outer circumferential edge face of the workpiece comprising:the rotating mechanism can synchronously rotate the workpiece and the imitating form having almost identical outline to the outline of the workpiece, at the same rotating axis center; andthe coating mechanism comprising:a pressing roller that can rotate with the imitating form while being pressed against the outer circumferential edge face of the imitating form;a coating part including a coating roller that is pressed against the outer circumferential edge face of the workpiece and rotates with the workpiece to apply the film-forming liquid to the outer circumferential edge face of the workpiece; anda rotary transmission unit that synchronously rotates the pressing roller and the coating roller, which have almost identical outline.

Using the coating apparatus according to the first aspect of the present invention, the rotating mechanism enables synchronized rotation of the workpiece and the imitating form having almost the same outline and the same rotating axis center.

By the coating mechanism, the pressing roller and the coating roller are pressed against the outer circumferential edge face of the imitating form and the workpiece, respectively. It is possible to synchronously rotate the pressing roller and the coating roller, which have almost identical outline, by means of the rotary transmission unit.

Therefore, the rotational motion of the imitating form and the pressing roller can be synchronized with the rotational motion of the workpiece and the coating roller.

The presence of the imitating form enables the coating roller to contact the outer circumferential edge face of the workpiece according to the shape of the workpiece (in other words, regardless of the shape of the workpiece) while rotating the coating roller.

It is also possible to precisely apply the film-forming liquid to the outer circumferential edge face of the workpiece with a coating width less than the thickness of the workpiece.

Even if the workpiece is thin and prone to damage such as cracks and breaks, the presence of the imitating form limits the pressing force of the coating roller against the outer circumferential edge face of the workpiece and prevents damage to the workpiece.

The coating apparatus according to a second aspect of the present invention is characterized by the coating mechanism comprising:a copying position adjustment mechanism that enables adjustment of the position of the pressing roller so that it moves along the outer circumferential edge face of the imitating form, while synchronizing the change in the distance from the center of rotation of the imitating form to the contact point between the imitating form and the pressing roller accompanied by rotation of the imitating form according to the first aspect of the present invention.

Using the coating apparatus according to the second aspect of the present invention, even when the distance from the center of rotation of the imitating form to the contact point between the imitating form and the pressing roller changes as the imitating form rotates (for example, when the workpiece and imitating form are non-circular), the position of the pressing roller is adjusted accurately by the copying position adjustment mechanism in synchronization with the change in distance so that the pressing roller rotates with the outer edge of the imitating form pressed against it.

The position of the coating roller will also be precisely adjusted in synchronization with this operation, so that the coating roller rotates with the coating roller pressed against the outer circumferential edge face of the workpiece, in synchronization with the change in distance.

Therefore, even if the workpiece is not only circular but also non-circular, the film-forming liquid can be precisely applied to the outer circumferential edge face of the workpiece with a coating width less than the thickness of the workpiece.

The coating apparatus according to a third aspect of the present invention is characterized by the copying position adjustment mechanism comprising:a moving mechanism that enables the attaching member to which the pressing roller, the coating part and the rotary transmission unit are operably attached to move in a first direction along a straight line connecting the center of rotation of the imitating form and the center of rotation of the pressing roller; anda pressing adjustment part that enables the pressing adjustment of the attaching member attached to the moving mechanism in the first direction according to the second aspects of the present invention.

Using the coating apparatus according to the third aspect of the present invention, the moving mechanism enables the attaching member to move in the first direction, and the pressing adjustment part enables the attaching member attached to the moving mechanism to adjust the pressure in the first direction.

Therefore, the attaching member can be moved in the first direction with the pressing roller, the coating part, and the rotation transmission mechanism integrated and with the pressing roller pressed against the imitating form so that it moves along the outer circumferential edge face of the imitating form.

This prevents misalignment of the axis of rotation of the pressing roller and the coating roller during the coating operation, and further improves the accuracy of the operation of pressing the coating roller against the workpiece so that it moves along the outer circumference shape of the workpiece.

The coating apparatus according to a fourth aspect of the present invention is characterized by the coating mechanism comprising:a coating roller pressing part, which adjust the power of pressing coating roller to the outer circumferential edge face of the workpiece according to any one of the first through third aspects of the present invention.

Using the coating apparatus according to the fourth aspect of the present invention, the coating roller pressing part moderately adjusts the force with which the coating roller presses down on the outer circumferential edge face of the workpiece, so that the film-forming liquid can be applied to the outer circumferential edge face of the workpiece with a constant pressing force.

The coating apparatus according to a fifth aspect of the present invention is characterized by the coating roller pressing part comprising:a elastic member, which arranged with variable force in a second direction along a straight line connecting the center of rotation of the workpiece and the center of rotation of the coating roller according to the fourth aspect of the present invention.

Using the coating apparatus according to the fifth aspect of the present invention, the elastic member can be adjusted so that the pressing force of the coating roller against the workpiece is less than the pressing force of the pressing roller against the imitating form.

Therefore, the film-forming liquid can be precisely applied to the outer circumferential edge face of the workpiece with the desired coating width and thickness while the coating roller is lightly pressed against the outer circumferential edge face of the workpiece. It can also enhance the prevention of damage to the workpiece.

The coating apparatus according to a sixth aspect of the present invention is characterized by the rotary transmission unit comprising:a first transmission unit for transmitting the rotation of the pressing roller;a second transmission unit for transmitting the rotation from the first transmission unit; anda third transmission unit for transmitting the rotation from the second transmission unit to the coating roller, wherein the first transmission unit comprises:a first rotary transmission part for rotating together with the shaft of rotation of the pressing roller, wherein the second transmission unit comprises:a first rotary transmission shaft which is attached to a second rotary transmission part rotating synchronously with the first rotary transmission part at one end and a third rotary transmission part rotating synchronously with the second rotary transmission part at the other end, wherein the third transmission unit comprises:a fourth rotary transmission part which is attached to the rotating shaft of the coating roller and rotates synchronously with the third rotary transmission part; anda swaying arm that supports the rotating shaft of the coating roller in a form that enables the coating roller to sway around the first rotary transmission shaft according to any one of the first through fifth aspects of the present invention.

Using the coating apparatus according to the sixth aspect of the present invention, the rotation of the pressing roller is synchronously transmitted to the coating roller via the first rotary transmission unit, the second rotary transmission unit, the first rotary transmission shaft, the third rotary transmission unit, and the fourth rotary transmission unit, and the coating roller is supported in a swayable form by the swaying arms around the first rotary transmission shaft.

The configuration is such that the rotation of the pressing roller is synchronously transmitted to the coating roller, and the force to press the coating roller against the outer circumferential edge face of the workpiece is easily adjusted.

The coating apparatus according to a seventh aspect of the present invention is characterized by the coating part comprising:a liquid supply section to supply film-forming liquid to the outer circumferential edge face of the coating roller; anda liquid scraper provided with a coating groove to form a coating width less than or equal to the thickness of the workpiece and arranged to be in contact with the outer circumferential edge face of the coating roller according to any one of the first through sixth aspects of the present invention.

Using the coating apparatus according to the seventh aspect of the present invention, the film-forming liquid is supplied from the liquid supply section to the outer circumferential edge face of the coating roller, and as the coating roller rotates, the liquid scraping section scrapes off the film-forming liquid in areas other than the coating groove areas, so that a linear film-forming liquid in the form of a coating groove is precisely applied to the outer circumferential edge face of the coating roller.

Therefore, by rotating the workpiece and the coating roller in the companion direction with the outer circumferential edge face portion of the coating roller coated with the linear film-forming liquid pressed against the outer circumferential edge face of the workpiece, the linear film-forming liquid is transferred to the outer circumferential edge face of the workpiece.

Since the coating groove is shaped to form a coating width less than the thickness of the workpiece, the film-forming liquid can be precisely applied to the outer circumferential edge face of the workpiece with a coating width less than the thickness of the workpiece.

The coating apparatus according to an eighth aspect of the present invention is characterized by the rotating mechanism comprising:a holding part to hold the workpiece; anda imitating form attachment part to which the imitating form is removably attached according to any one of the first through seventh aspects of the present invention.

Using the coating apparatus according to the eighth aspect of the present invention, the workpiece is held in the holding section and the imitating form can be attached to and detached from the imitating form mounting section.

Therefore, the workpieces can be easily replaced and, depending on the type of workpieces, the imitating forms can be installed with a shape that is almost identical to the outer shape of these workpieces. Therefore, a single apparatus can repeatedly coat the outer circumferential edge faces of many types of workpieces with different shapes, highly versatile apparatus can be realized.

The coating apparatus according to a ninth aspect of the present invention is characterized by the rotating mechanism comprising:a first rotating shaft connecting the holding part and the imitating form attachment part; anda second rotating shaft connected coaxially to the first rotating shaft and rotatable by a rotary drive force from a driver, whereinthe holding part, the first rotating shaft and the second rotating shaft have a suction path for adsorbing and holding the workpiece in the holding part according to the eighth aspect of the present invention.

Using the coating apparatus according to the ninth aspect of the present invention, the rotating mechanism is configured so that the first and second rotation shafts are connected on the same axis, allowing easy attachment and removal of the imitating form to and from the imitating form attachment section. Since the suction path is formed, the workpiece can be suctioned and held in the holding section, and the workpiece can be easily attached and detached.

The coating apparatus according to a tenth aspect of the present invention is characterized by the outer circumference length of the pressing roller is longer than the outer circumference length of the imitating form according to any one of the first through ninth aspects of the present invention.

Using the coating apparatus according to the tenth aspect of the present invention, since the outer circumference length of the pressing roller is longer than the outer circumference length of the imitating form, the rotation of the pressing roller is less than one revolution when the imitating form makes one revolution. So, during one revolution of the pressing roller, in other words, during one revolution of the coating roller, the film-forming liquid can be applied to the entire circumference of the outer circumferential edge face of the workpiece.

The coating apparatus according to an eleventh aspect of the present invention is characterized by the rotary transmission unit comprising:a fourth transmission unit that has a fifth rotary transmission part having the same outline as the coating roller and enables synchronized rotation of the fifth rotary transmission part and the coating roller around the same rotating axis center; anda fifth transmission unit that enables synchronized rotation of the pressing roller and the fifth rotary transmission part according to any one of the first through fifth aspects of the present invention.

Using the coating apparatus according to the eleventh aspect of the present invention, the fifth transmission mechanism synchronously rotates the pressing roller and the fifth rotation transmission unit, and the rotation of the fifth rotation transmission unit is synchronously transmitted to the coating roller via the fourth transmission mechanism. Therefore, the fifth transmission mechanism and the fourth transmission mechanism can reliably rotate the pressing roller and the coating roller synchronously. And the rotational motion of the imitating form, which rotates together with the pressing roller, and the rotational motion of the workpiece, which rotates together with the coating roller, can also be synchronized.

The coating apparatus according to a twelfth aspect of the present invention is characterized by the fifth transmission unit comprising:a sixth rotary transmission part that can rotate together with the pressing roller;a seventh rotary transmission part that has the same outline as the sixth rotary transmission part and can rotate together with the fifth rotary transmission part; anda second rotary transmission shaft that enables synchronized rotation of the sixth and seventh rotary transmission part according to the eleventh aspects of the present invention.

Using the coating apparatus according to the twelfth aspect of the present invention, the sixth and seventh rotary transmission part rotate synchronously via the second rotary transmission shaft, which causes the pressing roller and the fifth rotary transmission section to rotate synchronously, and the rotation of the fifth rotary transmission part is transmitted synchronously to the coating roller by the fourth transmission mechanism. Therefore, it is possible to synchronously rotate the pressing roller and the coating roller with high accuracy using a simple configuration.

The coating apparatus according to a thirteenth aspect of the present invention is characterized by the second rotary transmission shaft comprising a deflectable shaft or a universal joint according to the twelfth aspects of the present invention.

Using the coating apparatus according to a thirteenth aspect of the present invention, the second rotary transmission shaft is configured with a deflectable shaft or with a universal joint, so that even if some misalignment (eccentricity) occurs in the axial direction of rotation between the pressing roller and the coating roller during coating operation, the pressing roller and the coating roller can be rotated synchronously with high accuracy while absorbing or mitigating the misalignment.

The coating apparatus according to a fourteenth aspect of the present invention is characterized by the rotary transmission unit comprising:a eighth rotary transmission part rotatable together with the sixth rotary transmission part; anda driving part that rotates and drives the eighth rotary transmission part according to the twelfth or thirteenth aspects of the present invention.

Using the coating apparatus according to the fourteenth aspect of the present invention, by driving the eighth rotary transmission part by the driving part, the rotational force of the eighth rotary transmission part is transmitted to the pushing roller via the sixth rotary transmission part. The rotational force of the eighth rotary transmission part is transmitted to the fifth rotary transmission part via the sixth rotary transmission part, the second rotary transmission shaft, and the seventh rotary transmission part, and then from the fifth rotary transmission part to the coating roller via the fourth transmission unit.

Therefore, the rotational drive force of the driving part is transmitted to the pressing roller and the coating roller, and the pressing roller and the coating roller can be rotated synchronously with high accuracy.

The coating apparatus according to a fifteenth aspect of the present invention is characterized by a tooth profile is formed on the outer circumference face of each of the imitating form, the pressing roller, the fifth rotary transmission part, the sixth rotary transmission part, the seventh rotary transmission part and the eighth rotary transmission part, which can be engaged with each other according to the fourteenth aspects of the present invention.

Using the coating apparatus according to the fifteenth aspect of the present invention, the imitating form, the pressing roller, the fifth rotary transmission part, the sixth rotary transmission part, the seventh rotary transmission part, and the eighth rotary transmission part each have tooth profiles on their outer circumference face that can be engaged with each other, thereby reducing synchronization timing deviations and increasing synchronization accuracy can be reached.

The coating apparatus according to a sixteenth aspect of the present invention is characterized by the fifth transmission unit comprising:a sixth rotary transmission part that can rotate together with the pressing roller;a seventh rotary transmission part that has the same outline as the sixth rotary transmission part and can rotate together with the fifth rotary transmission part;a first driving part that rotates and drives the sixth rotary transmission part; anda second driving part that rotates and drives the seventh rotary transmission part according to the eleventh aspects of the present invention.

Using the coating apparatus according to the sixteenth aspect of the present invention, the rotary driving force of the first driving part is transmitted to the pressing roller via the sixth rotational transmission part, the rotary driving force of the second driving part is transmitted to the fifth rotary transmission part via the seventh rotary transmission part, and the rotation of the fifth rotary transmission part is synchronously transmitted to the coating roller by the fourth transmission unit.

Therefore, it is possible to synchronously rotate the pressing roller and the coating roller with high accuracy by means of a configuration that synchronizes the rotary drive of the first driving part and the second driving part.

The coating apparatus according to a seventeenth aspect of the present invention is characterized by a tooth profile is formed on the outer circumference face of each of the imitating form, the pressing roller, the fifth rotary transmission part, the sixth rotary transmission part, and the seventh rotary transmission part, which can be engaged with each other according to the sixteenth aspects of the present invention.

Using the coating apparatus according to the seventeenth aspect of the present invention, the imitating form, the pressing roller, the fifth rotary transmission part, the sixth rotary transmission part, and the seventh rotary transmission part each have tooth profiles on their outer circumference face that can be engaged with each other, thereby reducing synchronization timing deviations and increasing synchronization accuracy can be reached.

The coating apparatus according to a eighteenth aspect of the present invention is characterized by the fifth transmission unit comprising:a sixth rotary transmission part that can rotate together with the pressing roller;a seventh rotary transmission part that has the same outline as the sixth rotary transmission part and can rotate together with the fifth rotary transmission part;a eighth rotary transmission part rotatable together with the sixth rotary transmission part:a first driving part that rotates and drives the eighth rotary transmission part;a ninth rotary transmission part rotatable together with the seventh rotary transmission part: anda second driving part that rotates and drives the ninth rotary transmission part according to the eleventh aspects of the present invention.

Using the coating apparatus according to the eighteenth aspect of the present invention, the rotary driving force of the first driving part is transmitted to the pressing roller via the eighth rotary transmission part and the sixth rotary transmission part, the rotary driving force of the second driving part is transmitted to the fifth rotary transmission part via the ninth and seventh rotary transmission part, and the rotation of the fifth rotary transmission part is synchronously transmitted to the coating roller by the fourth transmission unit.

Therefore, it is possible to synchronously rotate the pressing roller and the coating roller with high accuracy by means of a configuration that synchronizes the rotary drive of the first driving part and the second driving part.

The coating apparatus according to a nineteenth aspect of the present invention is characterized by a tooth profile is formed on the outer circumference face of each of the imitating form, the pressing roller, the fifth rotary transmission part, the sixth rotary transmission part, the seventh rotary transmission part, the eighth rotary transmission part and the ninth rotary transmission part, which can be engaged with each other according to the eighteenth aspects of the present invention.

Using the coating apparatus according to the nineteenth aspect of the present invention, the imitating form, the pressing roller, the fifth rotary transmission part, the sixth rotary transmission part, the seventh rotary transmission part, the eighth rotary transmission part, and the ninth rotary transmission part each have tooth profiles on their outer circumference face that can be engaged with each other, thereby reducing synchronization timing deviations and increasing synchronization accuracy can be reached.

The coating apparatus according to a twentieth aspect of the present invention is characterized by the rotary transmission unit comprising:a first driving part that rotates and drives the pressing roller; anda second driving part that rotates and drives the coating roller according to any one of the first through fifth aspects of the present invention.

Using the coating apparatus according to the twentieth aspect of the present invention, the rotary driving force of the first driving part is transmitted to the pressing roller, and the rotary driving force of the second driving part is transmitted to the coating roller.

Therefore, it is possible to synchronously rotate the pressing roller and the coating roller with high accuracy by synchronizing the rotary drive of the first driving part and the second driving part.

And the rotational motion of the imitating form, which rotates together with the pressing roller, and the rotational motion of the workpiece, which rotates together with the coating roller, can also be synchronized.

The coating apparatus according to a twenty first aspect of the present invention is characterized by the imitating form is shaped with a curved section on its periphery, the radius of the pressing roller is set to be less than or equal to the minimum radius of curvature of the curved section of the imitating form according to any one of the eleventh through twentieth aspects of the present invention.

Using the coating apparatus according to the twenty first aspect of the present invention, the radius of the pressing roller is set below the minimum radius of curvature of the curved sections of the imitating form, so that even if the imitating form has a shape with a plurality of curved sections with different degrees of curvature, the pressing roller can be accurately copied by pressing it against all the curved sections of the imitating form.

Therefore, the film-forming liquid can be precisely applied to the outer circumferential edge face of the workpiece (i.e. having a plurality of the curved sections with different degrees of curvature), which has the same approximate shape as the imitating form, with the coating roller, which has the same approximate shape as the pressing roller.

The coating apparatus according to a twenty second aspect of the present invention is characterized by a pressing roller guide is mounted on the imitating form, the pressing roller guide is configured to guide the pressing roller along the curved section of the imitating form according to the twenty first aspects of the present invention.

Using the coating apparatus according to the twenty second aspect of the present invention, the pressing rollers can be securely guided along the curved section of the imitating form with the pressing rollers pressed against the curved section, even if the curved section of the imitating form has a large degree of curvature, by providing the pressing roller guide.

This allows the coating roller to precisely apply the film-forming liquid to the outer circumferential edge face of the workpiece, even if the workpiece has a curved shape with a large degree of curvature.

The coating apparatus according to a twenty third aspect of the present invention is characterized by the rotating mechanism comprising:a holding part to hold the workpiece;a third rotating shaft with a holding part attachable on one end and a imitating form attachable on the other end; anda support part that rotatably supports the third rotating shaft, whereinthe holding part and the third rotating shaft have a suction path for adsorbing and holding the workpiece in the holding part according to any one of the eleventh through twenty second aspects of the present invention.

Using the coating apparatus according to the twenty third aspect of the present invention, the third rotating shaft is rotatably supported by the support part, and the holding part attachable is provided at one end of the third rotating shaft and the imitating form attachable is provided at the other end, so that the holding part and the imitating form can be easily attached and detached. The suction path is formed so that the workpiece can be held in the holding part by suction, and the workpiece can be easily attached or detached.

The coating apparatus according to a twenty fourth aspect of the present invention is characterized by the thickness of the outer circumferential edge face of the coating roller is less than or equal to the thickness of the outer circumferential edge face of the workpiece, wherein the coating part comprises:a liquid supply section to supply the film-forming liquid to the outer circumferential edge face of the coating roller;a liquid expansion part arranged to be in contact with the outer circumferential edge face of the coating roller; anda liquid scraper arranged to be in contact with the outer circumferential edge face of the coating roller according to any one of the eleventh through twenty third aspects of the present invention.

Using the coating apparatus according to the twenty fourth aspect of the present invention, the liquid supply section, the liquid expansion part, and the liquid scraper enable the film-forming liquid to adhere to the outer circumferential edge surface of the coating roller only, spreading the film-forming liquid without the film-forming liquid protruding from the outer circumferential edge surface.

The coating apparatus according to a twenty fifth aspect of the present invention is characterized by the liquid expansion part has a plurality of micro-grooves formed in the direction of rotation of the coating roller on the contact surface with the outer circumferential edge face of the coating roller according to the twenty fourth aspects of the present invention.

Using the coating apparatus according to the twenty fifth aspect of the present invention, the liquid expansion part is provided with a plurality of micro-grooves on the contact surface with the outer circumferential edge face of the coating roller, so that the film-forming liquid can adhere to the outer circumferential edge face of the coating roller while spreading it thinly and even. The coating the outer circumferential edge face of the workpiece can also be performed more neatly.

DESCRIPTION OF EMBODIMENTS

The preferred embodiments of the coating apparatus according to the present invention are described below by reference to the Figures.

The following embodiments of the invention are suitable specific examples of the invention and are subject to various technically preferred limitations, but the scope of the invention is not limited to these embodiments unless specifically stated to limit the invention in the following description.

FIG.1is a plan view showing an essential part configuration of the coating apparatus according to a first embodiment of the present invention;

FIG.2is a cross-sectional view showing an essential part of the II-II line inFIG.1; and

FIG.3is a cross-sectional view showing an essential part of the III-III line inFIG.1.

InFIGS.2and3, hatching showing cross sections is omitted for convenience of illustration.

A coating apparatus10is a device that allows film-forming liquid3to be applied with precision only to the outer circumferential edge face2a(FIG.2) of a workpiece2. the coating apparatus10has a rotating mechanism20that rotates the workpiece2and a coating mechanism30that applies the film-forming liquid3to the outer circumferential edge face2aof the workpiece2that is rotated by the rotating mechanism20. the rotating mechanism20and the coating mechanism30are located at the support base11.

In the present embodiment, it is assumed that the workpiece2to be coated is a thin lens with a non-circular shape for smart glasses, but the type, shape, size, etc. of the workpiece2are not limited to this.

Applicable the workpiece2can include various types of thin-plate-shaped components such as glass, lenses, mirrors, films, plastics and other resins, metals, or electronic circuit boards, regardless of whether they are circular or noncircular.

The rotating mechanism20has a holding part21that holds the workpiece2and a imitating form attachment part23to which a imitating form22, which has the same external shape as the workpiece2, is attached. The workpiece2held by the holding part21and the imitating form22attached to the imitating form attachment part23can rotate synchronously around the same rotating axis (A-axis).

The rotating mechanism20comprises a first rotating shaft24, which connects the holding part21and the imitating form attachment part23, and a second rotating shaft25, which is connected to the first rotating shaft24on the same axis (A axis) and can be rotated by rotational driving power from a driver27. The driver27consists of a high-precision rotary motor, such as a servo motor, for example, and the rotary driving power of the driver27is transmitted to the second rotating shaft25via a belt pulley mechanism27a. The second rotating shaft25is mounted in a bearing, such as a ball bearing, for example.

Rotation control of the second rotating shaft25by the driver27may be performed at a constant rotational speed, or rotational control may be performed at a varying rotational speed depending on the shape of the imitating form22.

The holding part21, the first rotating shaft24, and the second rotating shaft25are formed with a suction path26for holding the workpiece2in the holding part21by suction, and a vacuum device such as a vacuum pump or ejector, not shown, is connected to the lower end portion of the second rotating shaft25, which allows suction operation by the vacuum device.

Thus, the holding part21functions as a table to suction and hold the workpiece2. The configuration is such that the workpiece2is precisely positioned and placed on the top surface of the holding part21in an orientation that overlaps the imitating form22in plan view using an industrial robot such as a handling robot, which is not shown in the figure.

The imitating form22is configured to be detachable from the imitating form attachment part23, and in the present embodiment, the second rotating shaft25is inserted and attached to the center of rotation of the imitating form22. The imitating form22is, for example, made of metal and molded into the same shape as the outline of the workpiece2.

The coating mechanism30consists of a pressing roller31(FIGS.2and3), a coating part32including a coating roller33, a rotary transmission unit40(FIGS.2and3), a imitating position adjustment mechanism50, and a coating roller pressing part60.

The pressing roller31is pressed against a outer circumferential edge face22aof the imitating form22and is axially supported on a pressing roller rotating shaft41aso that it rotates about the center of the B axis according to the rotation of the imitating form22by the rotating mechanism20.

The pressing roller31, for example, is made of metal, has a predetermined hardness, and its outer surface has a predetermined surface roughness to enable it to rotate in companion with the imitating form22.

The coating roller33is axially supported by a coating roller rotating shaft43aso that it is pressed against the outer circumferential edge face2aof the workpiece2and applies the film-forming liquid3with a coating width less than the thickness of the workpiece2and rotating about the center of the D axis. The coating roller33is, for example, made of metal.

The pressing roller31and the coating roller33are circular in plan view and have the same external shape. The outline size of the pressing roller31is preferably designed so that its outer circumference length is longer than that of the imitating form22.

According to this configuration, the coating roller33, which has the same outline as the pressing roller31, can apply the film-forming liquid3to the entire circumference of the outer circumferential edge face2aof the workpiece2during one rotation.

The coating part32also has a liquid supply section34, a liquid scraper part35, and a liquid receiver36(FIGS.2and3) located near the outer surface of the coating roller33.

The liquid supply section34comprises a mechanism for supplying the film-forming liquid3to a outer circumferential edge face33aof the coating roller33, such as a nozzle part that discharges3supplied from a liquid holding part, not shown, into the outer circumferential edge face33a.

The liquid scraper part35has a coating groove35a(FIG.3) to form a coating width less than the thickness of the workpiece2, and consists of a mechanism including a scraping plate (scraper) or the like that is arranged to be in contact with the outer circumferential edge face33aof the coating roller33. The excess the film-forming liquid3scraped off by the liquid scraper part35is collected in the liquid receiver36.

The order of arrangement of the liquid supply section34and the liquid scraper part35is designed according to the direction of rotation of the coating roller33so that the film-forming liquid3fed from the liquid supply section34to the outer circumferential edge face33aof the coating roller33is scraped off by the liquid scraper part35.

The rotary transmission unit40is equipped with a mechanism that synchronously transmits the rotation of the pressing roller31to the coating roller33. The rotary transmission unit40preferably comprises a first transmission unit41(FIGS.2and3), which transmits the rotation of the pressing roller31, the second transmission unit42, which transmits the rotation from the first transmission unit41, and the third transmission unit43, which transmits the rotation from the second transmission unit42to the coating roller33.

The first transmission unit41comprises the pressing roller rotating shaft41a, which rotates with the pressing roller31, and a first gear41b, which is attached to the pressing roller rotating shaft41a. The pressing roller rotating shaft41ais attached to a bearing, for example, a ball bearing.

The second transmission unit42comprises a vertically oriented (first rotary transmission shaft) a rotary transmission shaft42a, a second gear42battached to the lower end (one end side) of the rotary transmission shaft42a, and the third gear42cattached to the upper end (other end) of the rotary transmission shaft42a.

The second gear42bis meshed with the first gear41bso as to rotate synchronously (companion rotation) with the first gear41b, and the third gear42cis mounted on the rotary transmission shaft42aso as to rotate synchronously with the second gear42b. The rotary transmission shaft42ais mounted on a bearing, for example, a ball bearing.

The third transmission unit43consists of the coating roller rotating shaft43a, which rotates with the coating roller33, the fourth gear43b, which is attached to the coating roller rotating shaft43a, and a swaying arm43c, which supports the coating roller rotating shaft43aon a shaft in a form that allows the coating roller33to pivot around the rotary transmission shaft42a.

The fourth gear43bis meshed with the third gear42cso as to rotate synchronously (companion rotation) with the third gear42c. the coating roller rotating shaft43ais mounted on a bearing, for example, a ball bearing.

In addition to the configuration in which the rotary transmission shaft42ais composed of one shaft, the rotating shaft portion of the swaying arm43cmay be composed of another rotating shaft, and the rotary transmission shaft42amay be divided into two rotating shafts to be rotated coaxially.

In the present embodiment, the first gear41band the second gear42bare examples of the first and second rotary transmission parts, and the third gear42cand the fourth gear43bare examples of the third and fourth rotary transmission parts. It is preferable to use gears with minimal backlash (the gap between tooth flanks when gears are meshed) for the first gear41b, the second gear42b, the third gear42c, and the fourth gear43b, preferably gears with no backlash, in order to improve the accuracy of synchronous rotation.

In another configuration example, the first gear41band the second gear42bmay be configured with a mechanism using a toothed pulley and toothed belt, and similarly, the third gear42cand the fourth gear43bmay be configured with a mechanism using a toothed pulley and toothed belt. In this case, too, it is preferable to use a toothed pulley and a toothed belt with minimal backlash, or more preferably, no backlash.

The imitating position adjustment mechanism50is a mechanism that allows the position of the pressing roller31to be adjusted to follow the outer circumferential edge face22aof the imitating form22while synchronizing with changes in the distance AE from the center of rotation (axis A) of the imitating form22to the contact point E (FIG.6) between the imitating form22and the pressing roller31with rotation of the imitating form22.

In the present embodiment, the imitating position adjustment mechanism50consists of a moving mechanism51and an attaching member pressing part52.

The moving mechanism51is a mechanism that allows a attaching member44, to which the pressing roller31, the coating part32, and the rotary transmission unit40are operably attached, to move in the first direction D1along the line AB (FIG.6) connecting the center of rotation (A axis) of the imitating form22and the center of rotation (B axis) of the pressing roller31(FIGS.2and3).

In the present embodiment, the moving mechanism51consists of two linear guide mechanisms arranged at predetermined intervals on the support base11.

The two linear guide mechanisms comprising the moving mechanism51have a guide rail51aand a slider51b, respectively, which are arranged in the first direction D1and move on the guide rail51a. The base of the attaching member44is mounted on the slider51b.

The attaching member pressing part52adjusts the pressure force to allow the attaching member44attached to the moving mechanism51to reciprocate in the first direction D1. In the present embodiment, the attaching member pressing part52comprises an air cylinder located at the support base11, wherein a piston rod52aof the air cylinder is oriented in the first direction D1and the tip of the piston rod52ais attached to the base of the attaching member44.

By using an air cylinder as the attaching member pressing part52, the configuration facilitates absorption or relaxation of the force when pressing the pressing roller31against the outer circumferential edge face22aof the imitating form22in accordance with changes in the distance between the A and B axes due to the rotation of the imitating form22. Pressing the pressing roller31to follow the shape of the outer circumference of the imitating form22, become more smoothly.

The coating roller pressing part60allows adjustment of the force that presses the coating roller33onto the outer circumferential edge face2aof the workpiece2.

In the present embodiment, the coating roller pressing part60is located on the side of the swaying arm43copposite the side on which the rotating mechanism20is located. The coating roller pressing part60comprises a elastic member61, which is positioned with variable force in the second direction D2(FIG.2) along the line AD connecting the center of rotation of the workpiece2(axis A) and the center of rotation of the coating roller33(axis D), and an attaching member62, to which the elastic member61is attached.

The attaching member62is attached to the top of the attaching member44. The elastic member61is composed of a compression coil spring, but may be composed of various spring members such as plate springs or other elastic materials such as air springs or rubber.

The following is a description of the operation of applying the film-forming liquid3to the outer circumferential edge face2aof the workpiece2using the coating apparatus10according to the first embodiment.

FIG.4is a figure showing an example of a workpiece, (a) is a plan view and (b) is a b-b cross section in (a). the workpiece2is a glass lens for smart glasses, for example, consisting of a non-circular lens with a width W of about the imitating position adjustment mechanism50to 60 mm, a height VW of about the coating mechanism30to 50 mm, and a thickness t of about 0.5 to 1 mm. The shape of the workpiece2is here an oval shape, but it may be an inverted trapezoidal or square shape.

FIG.5is a figure showing an example of a imitating form, (a) is a plan view and (b) is a b-b cross section in (a).

The imitating form22has the same shape as the outer shape of the workpiece2. The insertion hole22bis formed in the center of the imitating form22for insertion and attachment to the second rotating shaft25of the rotating mechanism20, and a attachment hole22c, a bolt or other fixture, is formed around the insertion hole22b, and the imitating form22can be attached to and detached from the imitating form attachment part23using said fixture.

The imitating form22is prepared for each type (shape) of the workpiece2. The imitating form22is preferably molded from a metal member. The imitating form22has a predetermined hardness and a predetermined surface roughness on its outer surface so that it can rotate around the pressing roller31in a companion rotation without misalignment (slippage). The imitating form22is preferably as thick as the thickness of the pressing roller31.

First, to start the coating operation, the workpiece2is placed on the holding part21of the coating apparatus10. The workpiece2is placed on the top surface of the holding part21by, for example, a handling robot, and is held in a suctioned position on the holding part21.

The workpiece2is installed on the holding part21so that the center of rotation of the workpiece2is aligned with the center of rotation of the imitating form22(center of rotation (A axis) of the first rotating shaft24and the second rotating shaft25) and the orientation of the workpiece2is aligned with the orientation of the imitating form22(so that the entire circumference of the workpiece2and the imitating form22overlap in plan view).

AlthoughFIGS.1to3show the state during the coating operation, it is possible to drive the imitating position adjustment mechanism50to evacuate the attaching member44to a predetermined position so that the imitating form22and the pressing roller31are a predetermined distance apart (e.g., 10 mm) when the workpiece2are attached and detached.

Once the workpiece2is in place on the top of the holding part21, the moving mechanism51and the attaching member pressing part52comprising the imitating position adjustment mechanism50are then driven to move the attaching member44so that the pressing roller31is pressed against the imitating form22.

When the pressing roller31is pressed against the imitating form22, the driver27of the rotating mechanism20is then driven, and the rotational driving force of the driver27drives the second rotating shaft25and the first rotating shaft24to rotate at a predetermined speed, and the imitating form22and the workpiece2begin to rotate synchronously.

When the imitating form22begins to rotate, the pressing roller31, which is being pressed against the imitating form22, begins to rotate in the companion direction to the imitating form22. The rotation of the pressing roller31is then transmitted to the coating roller33via the rotary transmission unit40(i.e., the pressing roller rotating shaft41a, the first gear41b, the second gear42b, the rotary transmission shaft42a, the third gear42c, the fourth gear43b, and the coating roller rotating shaft43a), and the coating roller33starts rotating synchronously with the pressing roller31.

In synchronization with the rotation of the coating roller33, a predetermined amount of the film-forming liquid3begins to be supplied from the liquid supply section34of the coating part32to the outer circumferential edge face33aof the coating roller33.

The supplied film-forming liquid3is scraped off by the liquid scraper part35, and the film-forming liquid3is applied to the outer circumferential edge face33aof the coating roller33in a linear pattern in the shape of the coating groove35a(coating width and thickness). Then, the film-forming liquid3is applied to the outer circumferential edge face2aof the workpiece2according to the rotation of the coating roller33.

FIG.6is schematic diagrams to explain the operation of the imitating form22and the pressing roller31during the coating operation by the coating apparatus10.

FIG.6(a)shows a scene in which the pressing roller31is pressed against the imitating form22, the imitating form22rotates to the left by rotational power from the driver27, and the pressing roller31rotates in a companion rotation (right rotation) following the rotation of the imitating form22.

FIG.6(b)shows the state when the imitating form22rotates 90 degrees left from the state inFIG.6(a).

FIG.6(c)shows the state when the imitating form22is rotated another 90 degrees to the left from the state inFIG.6(b).

The direction of rotation indicated by the arrow inFIG.6is an example, and it is also possible to configure the coating apparatus to rotate in the opposite direction to that of the arrow shown in the figure.

FIG.7is schematic diagrams to explain the operation of the workpiece2and the coating roller the coating roller33during the coating operation by the coating apparatus10.

FIG.7(a)shows a scene in which the coating roller33is pressed against the workpiece2, the workpiece2rotates left under rotational power from the driver27, and the coating roller33is applying the film-forming liquid3to the outer circumferential edge face2aof the workpiece2while rotating (right) in synchronization with the rotation of the pressing roller31transmitted via the rotary transmission unit40.

FIG.7(b)shows the state when the workpiece2is rotated 90 degrees left from the state inFIG.7(a).

FIG.7(c)shows the state when the workpiece2is rotated another 90 degrees to the left from the state shown inFIG.7(b).

FIG.7(d)shows the side of the workpiece2and the side of the coating roller33as viewed from the arrow X and Y directions shown inFIG.7(c).

FIG.7(a)shows the same timing state as shown inFIG.6(a); similarly,FIG.7(b)shows the same timing state as shown inFIG.6(b), andFIG.7(c)shows the same timing state as shown inFIG.6(c).

As shown inFIGS.6and7, the imitating form22and the workpiece2rotate synchronously with the rotational drive of the rotating mechanism20.

As shown inFIG.6, since the imitating form22is non-circular, as the imitating form22rotates, the distances AE, AE′, AE′, AE″ from the center of rotation of the imitating form22(axis A) to the contact points E, E′, E″ of the imitating form22and the pressing roller31changes.

In the state shown inFIG.6(b), the distance AE′ is shorter than the distance AE in the state shown inFIG.6(a). The position of the attaching member44is then adjusted by the imitating position adjustment mechanism50so that the position of the center of rotation (B axis) of the pressing roller31moves from B to B′ in synchronization with the change from distance AE to distance AE′ as the imitating form22rotates.

In the state shown inFIG.6(c), the distance is AE″, and the distance AE″ is longer than the distance AE′ in the state shown inFIG.6(b). Then, synchronizing the change from distance AE′ to distance AE″ with the rotation of the imitating form22, the attaching member44is adjusted by the imitating position adjustment mechanism50so that the position of the center of rotation (B axis) of the pressing roller31is shifted from B′ to B″.

Thus, the position of the pressing roller31is adjusted by the imitating position adjustment mechanism50so that the pressing roller31follows the outer circumferential edge face22aof the imitating form22, synchronizing with the change in the distance AE from the center of rotation (axis A) of the imitating form22to the point of contact E between the imitating form22and the pressing roller31as the imitating form22rotates.

The imitating form22and the workpiece2are arranged so that their centers of rotation are on the same axis (A axis) and their outer circumferences overlap each other in plan view, and the pressing roller31and the coating roller33are on the same axis (B and D axes) in the attaching member44where position adjustment is made by the imitating position adjustment mechanism50.

Therefore, the operation with the workpiece2and the coating roller33shown inFIG.7is basically synchronized with the operation with the imitating form22and the pressing roller31shown inFIG.6.

In other words, the position of the coating roller33(position of the center of rotation (D axis)) is adjusted by the imitating position adjustment mechanism50so that the coating roller33follows the outer circumferential edge face2aof the workpiece2, synchronizing the change in the distance AF from the center of rotation (A axis) of the workpiece2to the contact point F between the workpiece2and the coating roller33as the workpiece2rotates.

In addition, in the movement between the workpiece2and the coating roller33, the force of the coating roller33against the outer circumferential edge face2aof the workpiece2is adjustable by the elastic member61of the coating roller pressing part60.

That is, in the attaching member44, the pressing roller31and the coating roller33are arranged basically on the same axis (B and D axes), but the coating roller33is supported by the swaying arm43cin a form that allows it to pivot around the rotary transmission shaft42a. However, since the third gear42cattached to the rotary transmission shaft42aand the fourth gear43battached to the coating roller rotating shaft43aare engaged, the swing range (angle) of the coating roller33is limited to a small range.

Since the swaying arm43cis pressed by the elastic member61with variable force in the second direction D2(FIG.2), the pressing force when the coating roller33is pressed against the outer circumferential edge face2aof the workpiece2can be relieved and absorbed by the elastic member61.

Thus, it is possible to apply the film-forming liquid3with the coating roller33pressed against the outer circumferential edge face2aof the workpiece2with less force than the pressing roller31is pressed against the outer circumferential edge face22aof the imitating form22.

As shown inFIG.7(d), the film-forming liquid3supplied to the outer circumferential edge face33aof the coating roller33is scraped off by the liquid scraper part35except for the area where the coating groove35a(FIG.3) is formed by the liquid scraper part35, and is applied in a line with the shape of the coating groove35a(coating width and thickness).

The size of the coating groove35ais designed so that the coating width t1of the film-forming liquid3applied in a linear pattern is less than or equal to the thickness t of the workpiece2, and the coating thickness of the film-forming liquid3is less than several tens of micrometers, for example, for shading material. The shape of the coating groove35ais set according to the type and thickness of the workpiece2and the type of the film-forming liquid3.

AlthoughFIG.7(d)shows an example of a configuration in which the thickness of the coating roller33is greater than the thickness t of the workpiece2, in another configuration example, the thickness of the coating roller33may be configured with a paint width of t1less than the thickness t of the workpiece2.

The outer circumferential edge face33aportion of the coating roller33with the linear film-forming liquid3applied is pressed against the outer circumferential edge face2aof the workpiece2while rotating, so that the film-forming liquid3is applied (transferred) to the outer circumferential edge face2aof the workpiece2with a coating width of less than the thickness t of the workpiece2and with a predetermined coating thickness.

According to the coating apparatus10in the first embodiment, the rotating mechanism20allows synchronized rotation of the workpiece2held in the holding part21and the imitating form22attached to the imitating form attachment part23at the same rotation axis (A-axis) center.

By the coating mechanism30, the pressing roller31is rotated according to the rotation of the imitating form22with the pressing roller31pressed against the imitating form22, and the rotation of the pressing roller31is transmitted synchronously to the coating roller33by the rotary transmission unit40.

Therefore, with the coating roller33rotating synchronously with the pressing roller31and the coating roller33pressed against the outer circumferential edge face2aof the workpiece2rotating synchronously with the imitating form22, the film-forming liquid3is applied to the outer circumferential edge face2aof the workpiece2with a coating width less than the thickness of the workpiece2.

Even if the distance AE from the center of rotation (axis A) of the imitating form22to the contact point E between the imitating form22and the pressing roller31changes with the rotation of the imitating form22, which has a non-circular shape, the position of the pressing roller31is adjusted by the imitating position adjustment mechanism50in synchronization with the change in distance AE so that the pressing roller31rotates with the pressing roller31pressed against the outer circumferential edge face22aof the imitating form22, and the force pressing the coating roller33onto the outer circumferential edge face2aof the workpiece2is adjusted by the coating roller pressing part60.

Therefore, even if the workpiece2is not only circular but also noncircular, the film-forming liquid3can be precisely applied to the outer circumferential edge face2aof the workpiece2with a coating width less than the thickness t of the workpiece2.

According to the coating apparatus10, the imitating position adjustment mechanism50comprises the moving mechanism51and the attaching member pressing part52, wherein the moving mechanism51allows the attaching member44to move in the first direction D1and the attaching member pressing part52allows the attaching member44attached to the moving mechanism51to be pressure adjusted in the first direction D1.

Thus, the attaching member44can be moved in the first direction D1with the pressing roller31, the coating part32, and the rotary transmission unit40integrated and with the pressing roller31pressed against the imitating form22so that it moves along the circumferential shape of the imitating form22.

This prevents misalignment of the rotational axes (B and D axes) of the pressing roller31and the coating roller33during the coating operation, and further improves the accuracy of the operation to press the coating roller33against the workpiece2to move along the outer circumferential edge face2a.

According to the coating apparatus10, the coating roller pressing part60is equipped with the elastic member61, so that the elastic member61can adjust (relieve or absorb) the pressure force of the coating roller33against the workpiece2to be less than the pressure force of the pressing roller31against the imitating form22.

Therefore, with the coating roller33lightly pressed against the outer circumferential edge face2aof the workpiece2, the film-forming liquid3can be accurately applied to the outer circumferential edge face2aof the workpiece2with the desired coating width and thickness.

According to the coating apparatus10, the rotation of the pressing roller31is synchronously transmitted to the coating roller33via the first gear41b, the second gear42b, the rotary transmission shaft42a, the third gear42c, and the fourth gear43b, which constitute the rotary transmission unit40, and the coating roller33is configured to be pivotally supported by the swaying arm43cwith the rotary transmission shaft42aas a center.

This configuration enables a configuration in which the rotation of the pressing roller31is transmitted synchronously to the coating roller33and in which the force to push the coating roller33against the outer circumferential edge face2aof the workpiece2can be easily adjusted.

According to the coating apparatus10, since the coating part32is equipped with the liquid supply section34and the liquid scraper part35, the film-forming liquid3is supplied from the liquid supply section34to the outer circumferential edge face33aof the coating roller33, and as the coating roller33rotates, the film-forming liquid3is scraped off the portions except for the portion of the coating groove35aby the liquid scraper part35, so that a linear the film-forming liquid3in the shape of the coating groove35ais precisely applied and formed on the outer circumferential edge face33aof the coating roller33.

Therefore, by rotating the workpiece2and the coating roller33in the companion direction with the outer circumferential edge face33aportion of the coating roller33with the linear film-forming liquid3applied pressed against the outer circumferential edge face2aof the workpiece2, the linear film-forming liquid3is transferred to the outer circumferential edge face2aof the workpiece2and the film-forming liquid3can be applied to the outer circumferential edge face2aof the workpiece2with precision with a coating width less than the thickness of the workpiece2.

According to the coating apparatus10, the rotating mechanism20is configured so that the first rotating shaft24and the second rotating shaft25are connected on the same axis (A axis), which makes it easy to attach the imitating form22to the imitating form attachment part23, and the suction path26is formed so that the workpiece2can be adsorbed and held in the holding part21.

According to the coating apparatus10, since the pressing roller31and the coating roller33have the same external shape, the rotational cycles of the pressing roller31and the coating roller33can be synchronized with the rotation of the imitating form22and2, and the application to the outer circumferential edge face2aof the workpiece2by the coating roller33can be performed with high accuracy.

According to the coating apparatus10, the circumferential length of the pressing roller31is longer than the circumferential length of the imitating form22, so that even if the imitating form22makes one rotation, the rotation of the pressing roller31is less than one revolution, and thus the film-forming liquid3can be applied to the outer circumferential edge face2aof the workpiece2during one rotation of the pressing roller31.

According to the coating apparatus10, since the imitating form22is configured to be detachable from the imitating form attachment part23, for each type of the workpiece2, the imitating form22of the same shape as the outer shape of these workpieces can be attached. A single apparatus can perform application to the outer edge surfaces of many types of workpieces with different shapes, making it a highly versatile apparatus.

In the coating apparatus10for the first embodiment, the rotational transmission force of the driver27is transmitted to the second rotating shaft25via the belt pulley mechanism27a, but the form of drive by the driver27is not limited to this.

In another embodiment, the rotational transmission force of the driver27may be transmitted to the rotary transmission shaft42aof the rotary transmission unit40via a belt pulley mechanism or gears. Alternatively, the second gear42band the third gear42cmay be configured to drive and control the rotary shafts of the second gear42band the third gear42c, respectively, to rotate synchronously at separate the driver27without connecting them at the rotary transmission shaft42a.

FIG.8is a plan view showing an essential part configuration of the coating apparatus according to a second embodiment of the present invention;

FIG.9is a cross-sectional view showing an essential part of the IX-IX line inFIG.8;

FIG.10is a cross-sectional view showing an essential part during the coating operation of the IX-IX line;

FIG.11is a cross-sectional view showing an essential part of the XI-XI line inFIG.10;

FIG.12is a cross-sectional view showing an essential part of the XII-XII line inFIG.10; and

FIG.13is a cross-sectional view showing an essential part of the XIII-XIII line inFIG.10.

InFIGS.9-13, hatching showing cross sections is omitted for convenience of illustration.

InFIG.8, the workpiece is omitted.

Components having the same functions as the coating apparatus10shown inFIGS.1-3are marked with the same symbols, and their descriptions are omitted here.

A coating apparatus10A is a apparatus that allows the film-forming liquid3to be applied to the outer circumferential edge face2ain the workpiece2B (FIGS.9,10,12, and13) with precision only to the outer circumferential edge face2a.

The coating apparatus10A has the rotating mechanism20A that rotates the workpiece2B and a coating mechanism30A that applies the film-forming liquid3to the outer circumferential edge face2aof the workpiece2B rotated by20A.

As shown inFIGS.9and10, the rotating mechanism20A consists of the workpiece2B and a imitating form22A, which has an outline identical to that of the workpiece2B, and can rotate synchronously around the same rotation axis (A axis).

The rotating mechanism20A has a holding part21A, a third rotating shaft28, and a housing29that hold the workpiece2B, and the housing29has a bearing, such as a ball bearing, that supports the third rotating shaft28in a rotatable manner.

As shown inFIGS.9and10, the coating mechanism30A consists of a pressing roller31A, the coating part32A including the coating roller33A, and a rotary transmission unit70(FIGS.9and10). The coating mechanism30A further comprises the imitating position adjustment mechanism50A (FIGS.8and9) and the coating roller pressing part60A (FIG.8).

As shown inFIGS.8and9, a cantilevered form bracket (support member)12is fixed on the support base11A of the coating apparatus10A.

The rotating mechanism20A is attached to one side of the one end side (tip side) of an arm12aof the bracket12.

The coating mechanism30A is attached to one side of the other end side of the arm12aof the bracket12through a first sliding part13and a first attaching board14, which has a vertical rectangular shape.

The first sliding part13allows the coating mechanism30A to move back and forth in the direction of extension (horizontal direction) of the arm12a, and consists of a linear guide mechanism including, for example, a linear guide13aand a slider13b. the first attaching board14is attached to the slider13b, and the coating mechanism30A is attached to the first attaching board14.

A second attaching board15is attached to the other side of one end side of the arm12aand an air cylinder16is attached to the second attaching board15.

A rod16aof the air cylinder16can move back and forth horizontally toward the other end side of the arm12a.

The air cylinder16is designed to be pressure regulated by a control unit, not shown, to control the advancing and retreating movement of the rod16a.

The tip of the rod16aof the air cylinder16is attached to one end of a L-type Connection tool18via a joint17. It is preferable to use a floating joint for the joint17that can absorb eccentricity and angular misalignment.

The other end of the L-type Connection tool18is attached to the first attaching board14. The above configuration allows the coating mechanism30A attached to the first attaching board14to move back and forth horizontally along the linear guide13aby controlling the reciprocating motion of the rod16aof the air cylinder16.

Thus, according to the coating apparatus10A in the second embodiment, the imitating position adjustment mechanism50A is composed of the air cylinder16and the first sliding part13.

The imitating position adjustment mechanism50A is a mechanism that allows the position of the coating mechanism30A, including the pressing roller31A, to be adjusted to the third direction D3(FIG.8) to follow the outer circumferential edge face22aof the imitating form22A, while synchronizing the change from the center of rotation (A-axis) of the imitating form22A to the contact point E (FIG.16) between the imitating form22A and the pressing roller31A, as the imitating form22A rotates.

the first sliding part13is an example of a moving mechanism and the air cylinder16is an example of a pressure adjustment unit.

The first sliding part13is a mechanism that allows the first attaching board14, to which the pressing roller31A, the coating part32A, and the rotary transmission unit70are movably attached, to move D3along a line connecting the center of rotation (A axis) of the imitating form22A and the center of rotation (B axis) of the pressing roller31A (FIGS.9and10).

Since the pressure adjustment section is composed of the air cylinder16, it is configured to easily absorb or relax the force when pressing the pressing roller31A to follow the outer circumferential edge face22aof the imitating form22A in response to changes in the distance between the A and B axes as the imitating form22A is rotated. This makes it possible to perform the operation of pressing the pressing roller31A to follow the outer circumference shape of the imitating form22A more smoothly.

The third rotating shaft28, which constitutes the rotating mechanism20A, has a holding part attachment28aon one end to which the holding part21A can be attached and a imitating form attachment part28bon the other end to which the imitating form22A can be attached, as shown inFIGS.9and10.

The suction path26is formed on the holding part21A and the third rotating shaft28to hold the workpiece2B in the holding part21A for suction, and a vacuum device such as a vacuum pump or ejector, not shown, is connected to the lower end of the third rotating shaft28via a pipe coupling or the like to enable suction operation.

Therefore, the holding part21A functions as a table for suction-holding the workpiece2B, and suction grooves are formed radially on its top surface.

The configuration is such that the workpiece2B is precisely positioned and placed on the top surface of the holding part21A in an orientation that overlaps the imitating form22A in plan view using an industrial robot such as a handling robot, which is not shown in the figure.

As shown inFIGS.9and10, the imitating form22A is configured to be detachable from the imitating form attachment part28b, and a hole is formed in the center of rotation of the imitating form22A into which the third rotating shaft28is inserted. The imitating form22A is made of a metal or other material molded into an approximate identical shape to the outer shape of the workpiece2B.

The outer circumference of the imitating form22A has minute tooth profiles that mesh with the minute tooth profiles formed on the outer circumference of the pressing roller31A, which will be described later, and the outer shape connecting the pitch points of these tooth profiles is designed to be the same shape as the outer shape of the workpiece2B.

In addition, a pressing roller guide22dis attached to the imitating form22A to guide the pressing roller31A along the curved portion of its circumference.

As shown inFIGS.9and10, the pressing roller31A, which constitutes the coating mechanism30A, is configured to be rotatable (rotatable in the companion direction) with the imitating form22A while pressed against the outer circumferential edge face22aof the imitating form22A, and is integrated with a roller shaft31bto rotate about the B axis center.

The outer surface of the pressing roller31A has a micro tooth profile that meshes with the micro tooth profile formed on the outer surface of the imitating form22A, and the pressing roller31A functions as a small diameter gear.

The pressing roller31A and the roller shaft31bare made of metal, for example, but may be made of other hard materials.

As shown inFIGS.9and10, a housing37is attached to the lower end of the first attaching board14, and the roller shaft31bis rotatably attached to a bearing in the housing37.

A smaller diameter bearing31cis also attached to the upper end of the pressing roller31A. the smaller diameter bearing31cis for passing the pressing roller guide22dof the imitating form22A and has an outer diameter slightly larger than that of the pressing roller31A.

As shown inFIGS.9and10, the coating roller33A is for applying the film-forming liquid3to the outer circumferential edge face the outer circumferential edge face2aof the workpiece2B while being pressed against the outer circumferential edge face2aof the workpiece2B and rotating in the companion direction with the workpiece2B, and is integrated with a roller shaft33b.

The thickness of the outer circumferential edge face33aof the coating roller33A is designed to be less than or equal to the thickness of the outer circumferential edge face2aof the workpiece2B, more preferably less than the thickness of the outer circumferential edge face2a.

The workpiece2B has a thin shape and the thickness of2A is, for example, between 0.2 mm and 1 mm. The workpiece2B may have a thickness of 1 mm or more. The coating roller33A and the roller shaft33bare made of metal, for example, but may be made of other hard materials.

The coating roller33A and the pressing roller31A have approximately the same diameter, more specifically, the pitch circle (reference circle) of the coating roller33A and the pressing roller31A have the same diameter.

The radius of the pressing roller31A is preferably set below the minimum radius of curvature among the curved portions of the outer circumference of the imitating form22A.

Since the pressing roller31A and the coating roller33A have the same diameter, the radius of the coating roller33A is also set below the smallest radius of curvature among the curved portions of the outer circumference of the workpiece2B.

According to this configuration, even if the imitating form22A has a complicated shape with curved portions with different degrees of curvature, the pressing roller31A can be accurately followed around the entire circumference of the outer circumferential edge face22aof the imitating form22A.

Since the pressing roller31A and the coating roller33A have the same diameter and the imitating form22A and the workpiece2B have the same shape, it is possible to precisely apply the film-forming liquid3to the entire circumference of the outer circumferential edge face2aof the workpiece2B by the coating roller33A even if the workpiece2B has a complicated shape with curved portions with different bends.

As shown inFIGS.9and10, the rotary transmission unit70is equipped with a mechanism for synchronous rotation of the pressing roller31A and the coating roller33A (in this case, rotation in the same direction and at the same rotational speed). The rotary transmission unit70comprises the fourth transmission unit71and the fifth transmission unit72.

The fourth transmission unit71is composed of a rotary transmission shaft71a, which has the same axis of rotation as the roller shaft33bof the coating roller33A, and the fifth gear71b, which is integrally provided at the lower end (one end) of the rotary transmission shaft71a, enabling synchronous rotation of the fifth gear71band the coating roller33A at the same axis of rotation center.

At the upper end of the first attaching board14, a housing76is attached via the second sliding part77that can slide horizontally. The rotary transmission shaft71ais rotatably mounted on a bearing in the housing76, and the roller shaft33bcan be mounted on its upper end (other end).

The fifth gear71bhas a minute tooth profile that meshes with the minute tooth profile formed on the outer circumference of the seventh gear72b, which will be described later, and the fifth gear71bfunctions as a small diameter gear.

The fifth gear71bhas the same diameter as the coating roller33A, more specifically, the pitch circle (reference circle) of the coating roller33A and the fifth gear71bhave the same diameter.

The fifth transmission unit72is located between the housing37and the housing76and is equipped with a mechanism to rotate the pressing roller31A and the fifth gear71bsynchronously (in this case, in the same rotational direction and at the same rotational speed).

The fifth transmission unit72comprises the sixth gear72a, the seventh gear72b, and a rotary transmission shaft72c.

The sixth gear72ais arranged to be rotatable (rotatable in the companion direction) together with the pressing roller31A.

The outer circumference of the sixth gear72ahas minute tooth profiles that mesh with the minute tooth profiles formed on the outer circumference of the pressing roller31A, and the sixth gear72afunctions as a large-diameter gearwheel.

The seventh gear72bhas the same diameter as the sixth gear72a, i.e., the same pitch circle (reference circle) diameter, and is arranged to be rotatable (rotatable in the companion direction) together with the fifth gear71b.

The outer circumference of the seventh gear72bhas minute tooth profiles that mesh with the minute tooth profiles formed on the outer circumference of the fifth gear71b, and the seventh gear72bfunctions as a large-diameter gearwheel.

The sixth gear72aand the seventh gear72bare connected by the rotary transmission shaft72cfor synchronous rotation. The rotary transmission shaft72cconsists of a deflectable shaft72dthat absorbs the shaft eccentricity. Instead of this the deflectable shaft72d, it may be composed of a shaft part including a universal joint.

The lower end (one end) of the rotary transmission shaft72cis rotatably mounted on a bearing provided in the housing37, and its upper end (the other end) is rotatably mounted on a bearing provided in the housing76.

The rotary transmission unit70has the eighth gear73, which is rotatable (rotatable in the companion direction) together with the sixth gear72a, and a driving motor74, which drives the eighth gear73to rotate. The driving motor74is attached to a motor attaching board75, and a rotating shaft74aof the driving motor74is attached to the eighth gear73. The driving motor74is composed of a high-precision rotary motor, such as a servo motor, for example.

The outer surface of the eighth gear73has a micro tooth profile that meshes with the micro tooth profile formed on the outer surface of the sixth gear72a.

When the rotating shaft74aof the driving motor74is driven to rotate, the eighth gear73rotates and its rotational force is transmitted to the pressing roller31A via the sixth gear72a, causing the pressing roller31A to rotate. At the same time, the rotational force of the eighth gear73is transmitted to the fifth gear71bvia the sixth gear72a, the rotary transmission shaft72c, and the seventh gear72b, causing the fifth gear71band the coating roller33A to rotate synchronously.

Thus, the rotary transmission unit70is configured to rotate the pressing roller31A and the coating roller33A synchronously.

The rotational force of the pressing roller31A is transmitted to the imitating form22A and the third rotating shaft28, causing the imitating form22A and the workpiece2B to rotate synchronously. Then, the film-forming liquid3is applied to the outer circumferential edge face2aof the workpiece2B by the coating roller33A, which rotates synchronously with the pressing roller31A.

The micro tooth shapes formed on the outer surface of the eighth gear73, the sixth gear72a, the pressing roller31A, the seventh gear72b, and the fifth gear71bare of the same shape. The shape of these tooth profiles is, for example, a concave tooth, the module is, for example, 0.1 to 0.8, preferably 0.2 to 0.4, and the pressure angle is, for example, but not limited to, 20 degrees.

As shown inFIGS.9and10, the coating part32A comprises the liquid supply section34A, which supplies the film-forming liquid3to the outer circumferential edge face33aof the coating roller33A, a bar coater35A, which is arranged to be in contact with the outer circumferential edge face33aof the coating roller33A, and a squeegee35B, which is arranged to be in contact with a outer circumferential edge part33c(FIG.17) of the coating roller33A.

The roller shaft33bis provided with a the liquid receiver36A that receives the extra film-forming liquid3that drips from the coating roller33A.

The liquid supply section34A consists of a coating base part34a, which is located above the housing76, a spacer34b, which is located above the coating base part34a, and a coating block34c, which is located above the spacer34b.

The coating base part34ahas a rounded corner rectangle on its top surface, a liquid reserve part34aa, and a tapered shape part34ab.

The tip of the tapered shape part34abis formed in the same arc as the outer circumferential edge face33aof the coating roller33A.

The spacer34bis formed of a thin plate less than the thickness of the coating roller33A. As shown inFIG.13, a hole34bahas the same shape as the liquid reserve part34aain the center and a slit hole34bbhas a tapered shape extending from the hole34ba. The tip of the slit hole34bbis formed in an arc shape that can contact the outer circumferential edge face33aof the coating roller33A.

The coating block34chas a tube part34ca, which has the same shape as the liquid reserve part34aa, and a tapered shape part34cbin the center.

The tapered shape part34cbof the coating block34cand the tapered shape part34abof the coating base part34aare identical in shape, and the spacer34bis interposed between the coating base part34aand the coating block34cto form a liquid channel34d(FIGS.10and13) in the slit hole34bbpart.

As shown inFIG.13, the bar coater35A is placed at the tip opening of the liquid channel34dof the liquid supply section34A.

The tip surface of the bar coater35A, i.e., the surface to be in contact with the outer circumferential edge face33aof the coating roller33A, has a plurality of microgrooves along the direction of rotation of the coating roller33A.

The groove spacing of the micro grooves is designed to be, for example, 0.05 mm to 0.2 mm, more preferably around 0.1 mm. The bar coater35A is an example of a liquid stretching part, as it is used to scrape off excess film-forming liquid3of the film-forming liquid3applied to3aof the coating roller33A while stretching it into a thin film.

In addition, the squeegee35B is placed at the tip of each of the coating base part34a's the tapered shape part34aband the coating block34c's the tapered shape part34cb.

As shown inFIG.17, each the squeegee35B is formed in the same arc shape as the circumference of the coating roller33A, and its tip is in a form that enables it to contact the outer circumferential edge part33con the upper and lower surfaces of the coating roller33A.

In other words, it is in the form of two the squeegee35B sandwiching the outer edge of the coating roller33A.

The squeegee35B are used to scrape off the film-forming liquid3adhered to the outer circumferential edge part33cof the coating roller33A and are an example of a liquid scraping part.

As shown inFIG.8,77is located between the housing76, to which the coating part32A is attached, and the first attaching board14.

Also, the elastic member61A and an attaching member62A, to which one end of the elastic member61A is attached, are placed between the housing76and the first attaching board14.

The elastic member61A is positioned with variable force along a line connecting the center of rotation of the workpiece2B (axis A) and the center of rotation of the coating roller33A (axis D) at the fourth direction D4(FIG.8).

The coating roller pressing part60A is comprised of the elastic member61A and the attaching member62A.

The coating roller pressing part60A allows fine adjustment of the force pressing the coating roller33A onto the outer circumferential edge face2aof the workpiece2B.

The operation of applying the film-forming liquid3to the outer circumferential edge face2aof the workpiece2B using the coating apparatus10A according to the second embodiment is described next.

FIG.14is a figure showing an example of a workpiece, (a) is a plan view and (b) is a b-b cross section in (a).

The workpiece2B is a lens for smart glasses, for example, a non-circular lens with a width and height of about the rotary transmission unit40to 60 mm and a thickness t of the outer circumferential edge face2aof about 0.2 to 1 mm.

The shape of the workpiece2B is, in this case, a rounded triangular shape with a curved section with a large curvature (curved corner).

The shape of the workpiece2B is not limited to this, and may be a rounded-angle inverted trapezoidal shape, a rounded-angle rectangular shape, a rounded-angle convex shape, or any other oval shape.

FIG.15is a figure showing an example of a imitating form, (a) is a plan view and (b) is a b-b cross section in (a).

The imitating form22A has a shape identical to the outline of the workpiece2B. In the center portion of the imitating form22A, the insertion hole22bis formed for insertion and attachment to the third rotating shaft28of the rotating mechanism20A. In the peripheral portion of the insertion hole22b, the attachment hole22c, a bolt or other fixture, is formed, and the imitating form22A can be attached to and detached from the imitating form attachment part28busing the fixture. In addition, the pressing roller guide22dis attached to the rounded corner of the imitating form22A.

The imitating form22A is prepared for each type (shape) of the workpiece2B.

The imitating form22A has tooth profiles formed on its outer circumference so that it can mesh with the tooth profiles formed on the outer circumference of the pressing roller31A and can rotate in a companion manner.

The shape of these tooth profiles is the same as the tooth profile formed on the pressing roller31A, e.g., coarse teeth, and the module is, for example, 0.1 to 0.8, preferably 0.2 to 0.4, and the pressure angle is, for example, 20 degrees, but not limited to this.

The imitating form22A is preferably molded from a metal member, but may also be molded from other hard materials.

First, in starting the coating operation, the workpiece2B is installed in the holding part21A of the coating apparatus10A.

The workpiece2B is installed on the top surface of the holding part21A by a handling robot, for example, and is held in a suctioned state on the holding part21A.

At this time, the workpiece2B is installed in the holding part21A so that the center of rotation of the workpiece2B is aligned with the center of rotation of the imitating form22A (center of rotation (A axis) of the third rotating shaft28) and the orientation of the workpiece2B is aligned with the orientation of the imitating form22A (so that the entire periphery of the workpiece2B and the imitating form22A overlap in plan view).

When attaching and detaching the workpiece2B, it is possible to drive the air cylinder16of the imitating position adjustment mechanism50A to move the coating mechanism30A out of position so that the imitating form22A and the pressing roller31A are a predetermined distance apart, as shown inFIGS.8and9.

Once the workpiece2B is in place on the top surface of the holding part21A, the air cylinder16comprising the imitating position adjustment mechanism50A is then driven to move the coating mechanism30A so that the pressing roller31A is pressed against the imitating form22A.

When the pressing roller31A is pressed against the imitating form22A, the driving motor74of the coating mechanism30A is then driven, and the eighth gear73begins to rotate at a predetermined speed by the rotational driving force of the driving motor74.

In turn, the sixth gear72a, which is engaged with the eighth gear73, rotates in the companion direction, and the pressing roller31A, which is also engaged with the sixth gear72a, begins to rotate in the companion direction.

When the sixth gear72arotates, the seventh gear72bconnected via the sixth gear72aand the rotary transmission shaft72crotates in the same direction as the sixth gear72a, synchronized with the rotation of the sixth gear72a. Furthermore, the fifth gear71b, which is engaged with the seventh gear72b, begins to rotate in the companion direction.

Then, the coating roller33A connected via the fifth gear71band the rotary transmission shaft71abegins to rotate in the same direction as the fifth gear71b.

The transmission of the rotational driving force from the driving motor74causes the pressing roller31A and the coating roller33A to rotate synchronously.

When the pressing roller31A and the coating roller33A begin to rotate, the imitating form22A with its tooth profile meshing with the pressing roller31A and each other begins to rotate in the companion direction, and the workpiece2B held by the holding part21A through the third rotating shaft28rotates in synchronization with that rotation.

As the coating roller33A rotates, the film-forming liquid3begins to be supplied from the liquid supply section34A of the coating part32A to the outer circumferential edge face33aof the coating roller33A. The supplied film-forming liquid3is scraped off the excess film-forming liquid3by the bar coater35A and the squeegee35B, and the film-forming liquid3is applied (adhered) in a line only to the outer circumferential edge face33aof the coating roller33A.

The film-forming liquid3applied to the outer circumferential edge face33aof the coating roller33A is then applied (transferred) to the outer circumferential edge face2aof the workpiece2B, which is rotating in the companion direction while being pressed against the outer circumferential edge face33aof the coating roller33A.

FIG.16is a schematic diagram illustrating the operation of the imitating form22A, the pressing roller31A, the sixth gear72a, and the eighth gear73during the coating operation by the coating apparatus10A.

FIG.16(a)shows a scene with the pressing roller31A pressed against the imitating form22A, the eighth gear73rotating to the right due to rotational power from the driving motor74, the sixth gear72arotating in companion (left) rotation following the rotation of the eighth gear73, the pressing roller31A rotating in companion (right) rotation following the rotation of the sixth gear72a, and the imitating form22A rotating in companion (left) rotation following the rotation of the pressing roller31A.

FIG.16(b)shows the state of the imitating form22A when it is rotated approximately 60 degrees to the left from the state shown inFIG.16(a).

The pressing roller guide22d(FIG.15) is positioned above the pressing roller31A (above the smaller diameter bearing31c(FIG.10)), and the structure is such that the position of the pressing roller31A at the curved corner of the imitating form22A is regulated (preventing misalignment) by the pressing roller guide22d.

As the imitating form22A rotates left and the curved corner of the imitating form22A approaches the pressing roller31A, a leftward pressure force is exerted on the pressing roller31A from the imitating form22A, and the imitating position adjustment mechanism50A (FIGS.8and9) moves the pressing roller31A, the sixth gear72a, and the eighth gear73(i.e., the coating mechanism30A) to the left for copying position adjustment.

FIG.16(c)shows the state of the imitating form22A when it is rotated another 60 degrees to the left from the state inFIG.16(b).

As the imitating form22A further rotates to the left and the curved corner of the imitating form22A moves away from the pressing roller31A, the imitating position adjustment mechanism50A (FIGS.8and9) exerts a rightward pressure on the imitating form22A from the pressing roller31A, causing the pressing roller31A, the sixth gear72a, and the eighth gear73(i.e., the coating mechanism30A) to move to the right, resulting in copying position adjustment.

The direction of rotation indicated by the arrow inFIG.16is an example, and it is also possible to configure the system to rotate in the opposite direction to that of the arrow shown in the figure.

FIG.17is a schematic diagram to illustrate the operation of the workpiece2B and the coating roller33A, the fifth gear71b, the seventh gear72bduring the coating operation by the coating apparatus10A.

FIG.17(a)shows the same timing state as that shown inFIG.16(a), and similarly,FIG.17(b)shows the same timing state as that shown inFIG.16(b), andFIG.17(c)shows the same timing state as that shown inFIG.16(c).

FIG.17(a)shows a scene in which the film-forming liquid3is being applied to the outer circumferential edge face2aof the workpiece2B with the coating roller33A pressed against the workpiece2B.

That is, the seventh gear72brotates in the same direction (left rotation) as the sixth gear72aconnected via the rotary transmission shaft72c, the fifth gear71brotates in a companion rotation (right rotation) following the rotation of the seventh gear72b, and the coating roller33A connected to the fifth gear71bvia the rotary transmission shaft71arotates in the same direction (right rotation) as the fifth gear71bwhile applying the film-forming liquid3to the outer circumferential edge face2aof the workpiece2B.

FIG.17(b)shows the state of the workpiece2B when it rotates 60 degrees to the left from the state shown inFIG.17(a).

As the workpiece2B rotates to the left and the curved corner of the workpiece2B approaches the coating roller33A, a leftward pressing force is exerted from the workpiece2B to the coating roller33A, and the imitating position adjustment mechanism50A (FIGS.8and9) moves the coating roller33A, the fifth gear71b, and the seventh gear72b(i.e., the coating mechanism30A) to the left to perform copying position adjustment.

At the same time, the pressing force of the coating part32A including the coating roller33A against the workpiece2B is finely adjusted by the coating roller pressing part60A (FIG.8) on the coating part32A.

FIG.17(c)shows the state of the workpiece2B when it is rotated another 60 degrees to the left from the state shown inFIG.17(b).

As the workpiece2B rotates further left and the curved corner of the workpiece2B moves away from the coating roller33A, the imitating position adjustment mechanism50A (FIGS.8and9) exerts a rightward pressure force on the workpiece2B from the coating roller33A, causing the coating roller33A, the fifth gear71b, and the seventh gear72b(i.e., the coating mechanism30A) to move to the right, resulting in copying position adjustment. At the same time, the pressing force of the coating part32A including the coating roller33A on the workpiece2B is finely adjusted by the coating roller pressing part60A (FIG.8) on the coating part32A.

FIG.17(d)shows an enlarged view of the side of the coating roller33A as seen from the arrow X direction shown inFIG.17(c), andFIG.17(e)shows the side of the workpiece2B as seen from the arrow Y direction shown inFIG.17(c).

The film-forming liquid3applied to the outer circumferential edge face33aof the coating roller33A is now only applied to the outer circumferential edge face2aof the workpiece2B.

As shown inFIGS.1and the joint17, the pressing roller31A and the coating roller33A rotate synchronously with the rotational drive of the driving motor74in the coating mechanism30A.

As shown inFIG.16, since the imitating form22A is non-circular, as the imitating form22A rotates, the distances AE, AE′, AE′, AE″ from the center of rotation (A-axis) of the imitating form22A to the contact points E, E′, E″ between the imitating form22A and the pressing roller31A will change.

In the state shown inFIG.16(b), the distance AE′ is longer than the distance AE in the state shown inFIG.16(a). The position of the coating mechanism30A is then adjusted by the imitating position adjustment mechanism50A (FIGS.8and9) so that the position of the center of rotation (B axis) of the pressing roller31A moves from B to B′ in synchronization with the change from distance AE to distance AE′ as the imitating form22A rotates.

In the state shown inFIG.16(c), the distance is AE″, and the distance AE″ is shorter than the distance AE′ in the state shown inFIG.16(b).

Then, synchronizing the change from distance AE′ to distance AE″ with the rotation of the imitating form22A, the position of the coating mechanism30A is adjusted by the imitating position adjustment mechanism50A so that the position of the center of rotation (B axis) of the pressing roller31A moves from B′ to B″.

Thus, the position of the pressing roller31A is adjusted by the imitating position adjustment mechanism50A so that the pressing roller31A follows the shape of the outer circumferential edge face22aof the imitating form22A while synchronizing with the change in the distance AE from the center of rotation (A-axis) of the imitating form22A to the contact point E between the imitating form22A and the pressing roller31A as the imitating form22A rotates.

The imitating form22A and the workpiece2B are arranged so that their centers of rotation are on the same axis (A axis) and their outer circumferences overlap each other in plan view, and the coating mechanism30A, whose position is adjusted by the imitating position adjustment mechanism50A, has the pressing roller31A and the coating roller33A on the same axis (B axis and D axis).

Therefore, the movement between the workpiece2B and the coating roller33A shown inFIG.17is basically synchronized with the movement between the imitating form22A and the pressing roller31A shown inFIG.16.

In other words, the position of the coating roller33A (position of the center of rotation (D axis)) is adjusted by the imitating position adjustment mechanism50A to follow the outer circumferential edge face33aof the coating roller33A, synchronizing with the change in the distance AF from the center of rotation (A axis) of the workpiece2B to the contact point F of the workpiece2B and the coating roller33A as the workpiece2B rotates.

In addition, in the operation between the workpiece2B and the coating roller33A, the force pressing the coating roller33A onto the outer circumferential edge face2aof the workpiece2B is adjustable by the elastic member61A of the coating roller pressing part60A (FIG.8).

In other words, in the coating mechanism30A, the pressing roller31A and the coating roller33A are basically arranged on the same axis (B and D axes), but the coating part32A, including the coating roller33A, is arranged in a form that allows sliding in the linear direction connecting the A and D axes by the second sliding part77, and the rotary transmission shaft72chas the deflectable shaft72d(FIGS.9and10).

However, the sliding range (distance) of the coating roller33A is limited to a very small range (a few mm or less).

Since the coating part32A is pressed by the elastic member61A with variable force to the fourth direction D4(FIG.8), the pressing force when the coating roller33A is pressed against the outer circumferential edge face2aof the workpiece2B can be relaxed or absorbed by the elastic member61A.

Therefore, it is possible to apply the film-forming liquid3with the coating roller33A pressed against the outer circumferential edge face2aof the workpiece2B with a force weaker than the force with which the pressing roller31A is pressed against the outer circumferential edge face22aof the imitating form22A.

As shown inFIG.17(d), the film-forming liquid3supplied to the outer circumferential edge face33aof the coating roller33A will be stretched into a thin film only on the outer circumferential edge face33a, as the excess film-forming liquid3is scraped off by the bar coater35A and the squeegee35B.

Since the thickness of the outer circumferential edge face33aof the coating roller33A is less than or equal to the thickness t of the workpiece2B, the coating width t1of the film-forming liquid3is less than or equal to the thickness t of the workpiece2B. The shape of the micro-groove of the bar coater35A is designed so that the coating thickness of the film-forming liquid3is less than several tens of micrometers, for example, for a light-shielding material.

The outer circumferential edge face33aportion of the coating roller33A with the film-forming liquid3applied is then pressed against the outer circumferential edge face2aof the workpiece2B while rotating, so that the film-forming liquid3is transferred and applied to the outer circumferential edge face2aof the workpiece2B with a coating width of less than the thickness t of the workpiece2B and with a predetermined coating thickness.

According to the coating apparatus10A in the second embodiment, the workpiece2B and the imitating form22A, which have the same outline, are configured by the rotating mechanism20A to rotate synchronously around the same rotating axis (A-axis).

With the pressing roller31A pressed against the outer circumferential edge face22aof the imitating form22A, and with the coating roller33A pressed against the outer circumferential edge face2aof the workpiece2B, by the coating mechanism30A respectively, the pressing roller31A and the coating roller33A can be rotated synchronously by the rotary transmission unit70.

Therefore, the rotational motion of the imitating form22A, which rotates together with the pressing roller31A, can be synchronized with that of the workpiece2B, which rotates together with the coating roller33A.

Even if the distance AE (FIG.16) from the center of rotation (A-axis) of the imitating form22A to the contact point E between the imitating form22A and the pressing roller31A changes as the imitating form22A, which has a noncircular shape, is rotated, the position of the pressing roller31A is precisely adjusted, synchronized with the change in distance AE so that the pressing roller31A rotates with the pressing roller31A pressed against the outer circumferential edge face22aof the imitating form22A, by the imitating position adjustment mechanism50A.

Synchronized with this action, the position of the coating roller33A will also be precisely adjusted, synchronized with the change in distance AE, so that the coating roller33A rotates with the coating roller33A pressed against the outer circumferential edge face2aof the workpiece2B.

Therefore, by providing the imitating form22A, which has a shape that is almost identical to the outer shape of the workpiece2B, the film-forming liquid3can be precisely applied only to the outer circumferential edge face2aof the workpiece2B, i.e., with a coating width less than the thickness of the workpiece2B, according to the shape of the workpiece2B (in other words, regardless of the shape of the workpiece2B).

Even if the workpiece2B is thin and prone to damage such as cracks and splits, the imitating form22A limits the pressing force of the coating roller33A against the outer circumferential edge face2aof the workpiece2B, thereby preventing damage to the workpiece2B.

According to the coating apparatus10A, the imitating position adjustment mechanism50A comprises the first sliding part13and the air cylinder16, wherein the first attaching board14attached to the coating mechanism30A is configured by the first sliding part13to be movable to the third direction D3.

The air cylinder16also allows the first attaching board14and the coating mechanism30A attached to the first sliding part13to be pressure-adjustable to the third direction D3.

Therefore, the first attaching board14can be moved to the third direction D3with the pressing roller31A, the coating part32A, and the rotary transmission unit70integrated and with the pressing roller31A pressed against the imitating form22A so that it follows the outer shape of the imitating form22A.

This prevents misalignment of the axes of rotation (B and D axes) of the pressing roller31A and the coating roller33A during the coating operation and enhances the accuracy of the operation of pressing the coating roller33A against the workpiece2B so that the coating roller33A follows the outer circumferential edge face2aof the workpiece2B.

According to the coating apparatus10A, since the coating roller pressing part60A comprises the elastic member61A and the second sliding part77, the elastic member61A and the second sliding part77make it possible to moderately adjust the force pressing the coating roller33A against the outer circumferential edge face2aof the workpiece2B.

For example, it is possible to adjust (relax or absorb) the pressing force of the coating roller33A against the workpiece2B so that the pressing force of the coating roller33A against the workpiece2B is less than the pressing force of the pressing roller31A against the imitating form22A.

Therefore, with the coating roller33A lightly pressed against the outer circumferential edge face2aof the workpiece2B, the film-forming liquid3can be precisely applied to the outer circumferential edge face2aof the workpiece2B with the desired coating width and thickness. In addition, the effect of preventing damage to the workpiece2B can be enhanced.

According to the coating apparatus10A, the fifth transmission unit72causes the pressing roller31A and the fifth gear71bto rotate synchronously, and the rotation of the fifth gear71bis transmitted synchronously to the coating roller33A via the fourth transmission unit71.

Therefore, the fifth transmission unit72and the fourth transmission unit71enable synchronized rotation of the pressing roller31A and the coating roller33A. Therefore, the synchronization accuracy between the rotational motion of the imitating form22A, which rotates together with the pressing roller31A, and that of the workpiece2B, which rotates together with the coating roller33A, can be increased. In addition, the spacing between the pressing roller31A and the coating roller33A can be adjusted by the fifth transmission unit72and the fourth transmission unit71.

According to the coating apparatus10A, the synchronized rotation of the sixth gear72aand the seventh gear72bvia the rotary transmission shaft72ccauses the synchronized rotation of the pressing roller31A, which is engaged with the sixth gear72a, and the fifth gear71b, which is engaged with the seventh gear72b, and the rotation of the fifth gear71bis transmitted synchronously to the coating roller33A via the rotary transmission shaft71a.

Therefore, it is possible to synchronously rotate the pressing roller31A and the coating roller33A with a simple configuration.

According to the coating apparatus10A, since the rotary transmission shaft72cis composed of the deflectable shaft72d, even if there is some misalignment (eccentricity) in the axial direction between the center of rotation of the pressing roller31A (B axis) and the center of rotation of the coating roller33A (D axis), it is possible to rotate the pressing roller31A and the coating roller33A synchronously with high accuracy while absorbing or mitigating such misalignment.

According to the coating apparatus10A, by driving the eighth gear73rotationally by the driving motor74, the rotational force of the eighth gear73is transmitted to the pressing roller31A via the sixth gear72a.

The rotational force of the eighth gear73is also transmitted to the fifth gear71bvia the sixth gear72a, the rotary transmission shaft72c, and the seventh gear72b, and then from the fifth gear71bto the coating roller33A via the rotary transmission shaft71a.

Therefore, the rotational drive force of the driving motor74is transmitted to the pressing roller31A and the coating roller33A, and the pressing roller31A and the coating roller33A can be rotated synchronously with high accuracy.

According to the coating apparatus10A, the outer surface of each of the imitating form22A, the pressing roller31A, the sixth gear72a, the eighth gear73, the seventh gear72b, and the fifth gear71bis formed with minute tooth profiles that can be engaged, thereby reducing deviations in synchronization timing of rotational movements and improving synchronization accuracy.

According to the coating apparatus10A, since the radius of the pressing roller31A is set below the minimum radius of curvature among the curved portions (curved corner portions) of the imitating form22A, even if the imitating form22A has a shape with multiple curved portions with different curvature, the pressing roller31A can be accurately imitated with all curved portions of the imitating form22A pressed against it.

Therefore, with the coating roller33A, which has the same outline shape as the pressing roller31A, the film-forming liquid3can be precisely applied to the outer circumferential edge face2a(i.e., having multiple curved sections with different degrees of curvature) of the workpiece2B, which has the same outline shape as the imitating form22A.

According to the coating apparatus10A, by providing the pressing roller guide22din the imitating form22A, even if the curved portion (curved corner, etc.) of the imitating form22A has a large degree of curvature (small radius of curvature), the pressing roller31A can be securely guided along the curved portion of the imitating form22A, with the pressing roller31A pressed against said curved portion.

As a result, even if the workpiece2B has a shape with a curved section with a large degree of curvature, the coating roller33A can accurately apply the film-forming liquid3to the outer circumferential edge face2aof the workpiece2B.

According to the coating apparatus10A, since the third rotating shaft28is rotatably supported by the housing29and the holding part attachment28ais provided at one end of the third rotating shaft28and the imitating form attachment part28bat the other end, the holding part21A and the imitating form22A can be easily attached and detached.

In addition, since the suction path26is formed on the third rotating shaft28and the holding part21A, the workpiece2B can be adsorbed and held on the holding part21A, and the workpiece2B can be easily attached and detached.

According to the coating apparatus10A, the liquid supply section34A, the bar coater35A, and the squeegee35B allow the film-forming liquid3to adhere to the outer circumferential edge face33aof the coating roller33A without protruding from the outer circumferential edge face33a, but only to that the outer circumferential edge face33awhile extending.

And since the thickness of the outer circumferential edge face33aof the coating roller33A is less than or equal to the thickness of the outer circumferential edge face2aof the workpiece2B, the film-forming liquid3can be applied while transferring cleanly from the outer circumferential edge face33aof the coating roller33A to the outer circumferential edge face2aof the workpiece2B.

According to the coating apparatus10A, the bar coater35A has a plurality of micro-grooves on its contact surface with the outer circumferential edge face33aof the coating roller33A, allowing the film-forming liquid3to adhere to the outer circumferential edge face33aof the coating roller33A while extending it thinly and evenly, the film-forming liquid3can be applied uniformly from the coating roller33A to the outer circumferential edge face2aof the workpiece2B, which has a thin plate shape.

FIG.18is a cross-sectional view showing an essential part configuration of the coating apparatus10B according to another embodiment of the present invention.

InFIG.18, hatching indicating the cross section is omitted for convenience of illustration. Components having the same functions as those of the coating apparatus10A shown inFIGS.8-10are marked with the same symbols, and their descriptions are omitted here.

The configuration in which the coating apparatus10B differs from the coating apparatus10A described above is the configuration of a rotary transmission unit70A comprising a coating mechanism30B.

In the coating apparatus10B, the fifth transmission unit72A comprising the rotary transmission unit70A has the sixth gear72athat can rotate together with the pressing roller31A, the seventh gear72bthat has the same outline as the sixth gear72aand can rotate together with the fifth gear71b, the first driving motor74A that drives the sixth gear72a, and the second driving motor74B that drives the seventh gear72b.

The sixth gear72ais attached to72e, which is rotatably supported on a shaft at the housing37. The seventh gear72bis attached to the seventh gear shaft72f, which is rotatably supported on a shaft at the housing76.

Two upper and lower motor attaching board75are attached to the first attaching board14, the first driving motor74A to the lower motor attaching board75and the second driving motor74B to the upper motor attaching board75.

In the coating apparatus10B, unlike the coating apparatus10A, without the rotary transmission shaft72cconnecting the sixth gear72aand the seventh gear72b, the rotational speeds of the first driving motor74A and the second driving motor74B are synchronously controlled to synchronize the rotation of the sixth gear72aand the seventh gear72b.

According to the coating apparatus10B, the rotational drive force of the first driving motor74A is transmitted to the pressing roller31A via the sixth gear72a, the rotational drive force of the second driving motor74B is transmitted to the fifth gear71bvia the seventh gear72band the rotation of the fifth gear71bis synchronously transmitted to the coating roller33A by the fourth transmission unit71.

Therefore, the pressing roller31A and the coating roller33A can be rotated precisely and synchronously by the configuration that synchronises the rotational drive of the first driving motor74A and the second driving motor74B.

FIG.19is a cross-sectional view showing an essential part configuration of the coating apparatus10C according to another embodiment of the present invention.

InFIG.19, hatching indicating the cross section is omitted for convenience of illustration. Components having the same functions as those of the coating apparatus10A shown inFIGS.8-10are marked with the same symbols, and their descriptions are omitted here.

The configuration in which the coating apparatus10C differs from the coating apparatus10A described above is the configuration of the rotary transmission unit70B comprising a coating mechanism30C.

In the coating apparatus10C, the fifth transmission unit72B comprising the rotary transmission unit70B has the sixth gear72athat can rotate together with the pressing roller31A, the seventh gear72bthat has the same outline as the sixth gear72aand can rotate together with the fifth gear71b, the eighth gear73that can rotate together with the sixth gear72a, the first driving motor74A that drives the eighth gear73, the ninth gear78that can rotate together with the seventh gear72b, and the second driving motor74B that drives the ninth gear78.

The sixth gear72ais attached to72e, which is rotatably supported on a shaft at the housing37. The seventh gear72bis attached to the seventh gear shaft72f, which is rotatably supported on a shaft at the housing76.

Two upper and lower motor attaching board75are attached to the first attaching board14, the first driving motor74A to the lower motor attaching board75and the second driving motor74B to the upper motor attaching board75.

In the coating apparatus10C, unlike the coating apparatus10A, without the rotary transmission shaft72cconnecting the sixth gear72aand the seventh gear72b, the rotational speeds of the rotating shaft74aof the first driving motor74A and the rotating shaft74aof the second driving motor74B are synchronously controlled to synchronise the rotation of83and72A, and the ninth gear78and the fifth transmission unit72B.

According to the coating apparatus10C, the rotational drive of the first driving motor74A is transmitted to the pressing roller31A via the eighth gear73and the sixth gear72a, the rotational drive of the second driving motor74B is transmitted to the fifth gear71bvia the ninth gear78and the seventh gear72b, and the rotation of the fifth gear71bis synchronously transmitted to the coating roller33A by the fourth transmission unit71.

Therefore, the pressing roller31A and the coating roller33A can be rotated precisely and synchronously by the configuration that synchronizes the rotational drive of the first driving motor74A and the second driving motor74B.

In yet another embodiment of coating apparatus, the roller shaft31bor the pressing roller31A may be driven rotationally by the first driving motor74A and the rotary transmission shaft71aor the fifth gear71bof the fourth transmission unit71may be driven rotationally by the second driving motor74B to synchronise the pressing roller31A and the coating roller33A.

INDUSTRIAL APPLICABILITY

The invention has a wide range of applications in the electronics industry and other fields dealing with thin lenses used in smart glasses, AR or VR goggles, etc., thin displays and cover lenses (cover glass) used in portable information terminals such as smartphones, smart watches and other wearable terminals.

DESCRIPTION OF REFERENCE SIGNS