Display system and display method

A display system includes: an imaging unit that images a mold from below; and a display unit that displays an image taken by the imaging unit together with a carry-in range of the mold in order to transport the mold in place between the stationary platen and the moving platen.

CROSS-REFERENCE TO RELATED APPLICATION

This application is based upon and claims the benefit of priority from Japanese Patent Application No. 2017-038929 filed on Mar. 2, 2017, the contents of which are incorporated herein by reference.

BACKGROUND OF THE INVENTION

Field of the Invention

The present invention relates to a display system and a display method of imaging and displaying a mold.

Description of the Related Art

Japanese Laid-Open Patent Publication No. 2002-028929 discloses a method of attaching a mold to an injection molding machine by bringing the mold between the stationary platen and the moving platen of the clamping device by means of a crane.

SUMMARY OF THE INVENTION

When a mold is transported from above by a crane into a space between the stationary platen and the moving platen in the clamping device of the injection molding machine, if the mold interferes with an obstacle (stationary platen, moving platen, tie bars, etc.), the mold and/or the obstacle will be damaged. To avoid this, the operator must operate the crane so that the mold will not interfere with any obstacle. The place where the operator controls the crane is around the injection molding machine. Particularly, in a case of a large injection molding machine, since there is a long distance from the operator to the place where the mold is carried into the injection molding machine, it is difficult to properly grasp the course through which the mold should be carried in. Therefore, in order to bring in the mold while avoiding interference with obstacles, skilled crane operation techniques are required and still a careful operation of the crane has taken time.

In view of the above, it is therefore an object of the present invention to provide a display system and a display method for assisting the carrying-in operation of a mold by displaying the state of a mold being conveyed between a stationary platen and a moving platen in a clamping device of an injection molding machine.

According to a first aspect of the present invention, a display system for displaying the state of a mold being transported from above into a space between a stationary platen and a moving platen that moves in a predetermined direction relative to the stationary platen in a clamping device includes: an imaging unit configured to image the mold from below; and

a display unit configured to display an image taken by the imaging unit together with a carry-in range of the mold in order to transport the mold in place between the stationary platen and the moving platen.

According to a second aspect of the present invention, a display method of displaying the state of a mold being transported from above into a space between a stationary platen and a moving platen that moves in a predetermined direction relative to the stationary platen in a clamping device includes: an imaging step of imaging the mold from below by an imaging unit; and a displaying step of displaying on a display unit the taken image together with a carry-in range of the mold in order to transport the mold in place between the stationary platen and the moving platen.

According to the present invention, it is possible to show the carry-in route of the mold to the operator who operates the crane. Therefore, the operator can put the mold in place between the stationary platen and the moving platen of the clamping device without causing the mold to interfere with the obstacles, and hence shorten the time for loading the mold.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

A display system and a display method according to the present invention will be detailed hereinbelow by describing preferred embodiments with reference to the accompanying drawings.

EMBODIMENT

FIG. 1is a view showing a configuration of a display system10and an injection molding machine12equipped with the display system10. The injection molding machine12includes an injector14, a clamping device16, and a machine base18that supports the injector14and the clamping device16. In the following description, an orthogonal XYZ coordinate system is set up where the X-direction (±X-direction), the Y-direction (±Y-direction), and the Z-direction (±Z-direction) are defined by the arrows shown in the drawings. It is assumed that the direction of gravity is the negative Z-direction (downward direction), and the injection molding machine12is set on the installation surface parallel to the XY-plane. The negative X-direction is the left direction inFIG. 1. The Y-direction is orthogonal to the paper surface ofFIG. 1, and the negative Y-direction is the front side of the paper surface ofFIG. 1.

The injector14has an injection cylinder20, and injects molten resin of the injection cylinder20through a nozzle20aof the injection cylinder20into a mold22(specifically, a cavity) of the clamping device16. The injector14and the clamping device16are installed on the machine base18so as to face each other along the X-direction in which the mold22is opened and closed. The axial direction of the injection cylinder20is parallel to the X-direction. The injector14injects molten resin into the mold22along the negative X-direction.

An unillustrated injection screw is arranged inside the injection cylinder20. This injection screw is moved in the positive X-direction rotating to charge and measure the molten resin. Then, the injection screw is moved in the negative X-direction toward the mold22, whereby the molten resin in the injection cylinder20is injected into the mold22through the nozzle20a. The injection cylinder20may be heated by, for example, a heater or the like to melt pellet resin supplied from an unillustrated hopper. The rotation of the injection screw and the movement thereof in the X-direction are actuated by an unillustrated drive source such as a servomotor.

The clamping device16holds the mold22and performs an opening and closing operation for opening and closing the mold22and a clamping operation for generating clamping force by means of an unillustrated toggle mechanism and an unillustrated driving mechanism including a servomotor. The mold22includes a stationary half22aattached to a stationary platen24and a moving half22battached to a moving platen26. In a molding process, the clamping device16moves the moving half22bin the closing direction (positive X-direction) to bring the moving half22binto contact with the stationary half22a, and further moves the moving half22bin the closing direction (positive X-direction) to clamp the mold. Further, after the molding process, the clamping device16moves the moving half22bin the opening direction (negative X-direction) to separate the moving half22bfrom the stationary half22a.

The clamping device16includes the stationary platen24, the moving platen26, a rear platen28, and four tie bars30(30ato30d). The four tie bars30are arranged parallel to the X-direction and connect the stationary platen24and the rear platen28. The moving platen26is disposed between the stationary platen24and the rear platen28so as to be movable in the X-direction along the four tie bars30. The stationary platen24, the rear platen28, and the moving platen26have substantially square shapes, and four tie bars30are provided at four corners, respectively. The rear platen28and the moving platen26are arranged so as to be slidable in the X-direction relative to the tie bars30, and the stationary platen24is fixed to the tie bars30so as not to slide in the X-direction.

Here, as shown inFIGS. 2A and 2B, the mold22with the stationary half22aand the moving half22bintegrated is transported from above (positive Z-direction) downward (in the negative Z-direction), toward between the stationary platen24and the moving platen26, by an unillustrated crane. After the mold22is conveyed in place between the stationary platen24and the moving platen26, the stationary half22ais attached to the stationary platen24and the moving half22bis attached to the moving platen26.

During this operation, in order to convey the mold22in place between the stationary platen24and the moving platen26without having the mold22interfere with obstacles such as the stationary platen24, the moving platen26, the tie bars30, etc., it is necessary to lower the mold22by the crane so that the mold22is positioned within a mold-transportable area IA. Therefore, the mold-transportable area IA is specified as a region surrounded by the stationary platen24, the moving platen26, and two tie bars30(30a,30cor30b,30d) provided along the Y-direction, as shown inFIG. 3. The length in the X-direction of the mold-transportable area IA is the distance between the surface on the negative X-direction side of the stationary platen24and the surface on the positive X-direction side of the moving platen26(seeFIG. 2A). The length in the Y-direction (width direction) of the mold-transportable area IA is the distance between the two tie bars30(30a,30cor30b,30d) provided along the Y-direction (seeFIG. 2B).

It is assumed in the present embodiment that the positions of the two tie bars30aand30bthat are on the negative Y-direction side and are arranged along the vertical direction (Z-direction) are coincident with each other in the Y-direction while the positions of the two tie bars30cand30dthat are on the negative Y-direction side and are arranged along the vertical direction (Z-direction) are coincident with each other in the Y-direction. Further, it is also assumed that the positions of the two tie bars30aand30cthat are on the positive Z-direction side and are arranged along the Y-direction are coincident with each other in the Z-direction while the positions the two tie bars30band30dthat are on the negative Z-direction side and are arranged along the Y-direction are coincident with each other in the Z-direction.

Returning to the explanation withFIG. 1, the display system10displays the transported state of the mold22being carried between the stationary platen24and the moving platen26from above. The display system10includes an imaging unit32, a control unit34, and a display unit36. The imaging unit32is arranged in the machine base18of the injection molding machine12so as to be able to capture the transported state of the mold22from the lower side (the negative Z-direction side) which is the conveying direction side. The imaging unit32is located between and below the stationary platen24and the moving platen26(seeFIG. 2A). Further, the imaging unit32is positioned between two tie bars30(30a,30cor30b,30d) arranged along the Y-direction (seeFIG. 2B).

The control unit34acquires image data (hereinafter, simply referred to as an image) captured by the imaging unit32. The control unit34outputs the acquired image to the display unit36and outputs information indicating a carry-in range IR to the display unit36. The control unit34has an unillustrated storage medium that stores information on carry-in range IR. The information on carry-in range IR stored in the storage medium is information indicating the carry-in ranges IR of different sizes corresponding to predetermined distances from the imaging unit32. The predetermined distance from the imaging unit32is a distance from the imaging unit32to a certain point in the upward direction (positive Z-direction). Here, the control unit34may perform image processing on the acquired image and output the processed image to the display unit36.

The carry-in range IR may be identical with the above-described mold-transportable area IA or may be smaller than the mold-transportable area IA. As shown inFIG. 3, by making the carry-in range IR smaller than the mold-transportable area IA, it is possible to further suppress the interference between the mold22and obstacles. The size of the carry-in range IR and the mold-transportable area IA indicates the size on the plane parallel to the XY-plane. Note that the imaging unit32also images the mold-transportable area IA surrounded by the stationary platen24, the moving platen26, and the four tie bars30.

The display unit36is arranged at a position visible from the crane's operator. The display unit36displays the state of the mold22being transported in order to assist transportation of the mold22into the clamping device16. The display unit36displays the image sent from the control unit34and the carry-in range IR based on the information on carry-in range IR. The displayed carry-in range IR is one having a size corresponding to a predetermined distance from the imaging unit32. The display position of the carry-in range IR on the image is determined according to the installation position of the imaging unit32and the predetermined distance from the imaging unit32. In this embodiment, for description simplicity, it is assumed that the carry-in range IR is smaller than the mold-transportable area IA.

FIG. 4is a diagram showing a display example of the display unit36. As shown inFIG. 4, on the display unit36the image captured by the imaging unit32is displayed with a frame F. This frame F shows the carry-in range IR, that is, the area surrounded by the frame F is the carry-in range IR. The displayed carry-in range IR shows a range having a size corresponding to the predetermined distance from the imaging unit32. For example, the carry-in range IR to be displayed may be one at a position 1 m high from the upper surface of the stationary platen24and the moving platen26. It is apparent that when the mold22is located in a short distance from the upper surface of the stationary platen24and the moving platen26, the displayed area surrounded by the stationary platen24, the moving platen26, and the tie bars30a,30csubstantially coincides with the carry-in range IR, the frame F may be hidden.

In this way, by displaying the carry-in range IR together with the image, it is possible to guide the mold22along the carry-in route. Therefore, the operator, as watching the image displayed on the display unit36, operates the crane so that the mold22displayed on the display unit36falls within the carry-in range IR, whereby it is possible to lead the mold22in place between the stationary platen24and the moving platen26without causing the mold22to interfere with any obstacles. Further, the time for loading the mold22can be shortened.

When the position of the mold22is located lower than the position at the predetermined distance from the imaging unit32, the mold22may be displayed greater than the carry-in range IR. In this case, the operator only needs to operate the crane so that the center of the mold22coincides with the center of carry-in range IR.

The displayed image of the mold22becomes smaller as the distance from the imaging unit32becomes longer, or becomes greater as the distance becomes shorter. Accordingly, the storage medium in the control unit34may store multiple pieces of information each representing a carry-in range IR of a size corresponding to a different predetermined distance from the imaging unit32. Further, the control unit34may output to the display unit36the multiple pieces of information indicating the multiple carry-in ranges IR stored in the storage medium. In this case, the display unit36displays image captured by the imaging unit32together with the multiple carry-in ranges IR based on the aforementioned multiple pieces of information.

For example as shown inFIG. 5, suppose that multiple pieces of information on carry-in ranges IR (IR1to IR3) of different sizes corresponding to respective distances A, B and C from the imaging unit32have been stored in the storage medium of the control unit34. In this case, as shown inFIG. 6the display unit36displays a frame F1showing the carry-in range IR corresponding to the distance A, a frame F2showing the carry-in range IR corresponding to the distance B, and a frame F3showing the carry-in range IR corresponding to the distance C, altogether. Since the distance A<the distance B<the distance C, the sizes of the displayed frames F become as follows: F1>F2>F3. The display positions of the carry-in ranges IR1, IR2, IR3on this image are determined depending on the installed position of the imaging unit32and the distances A, B, C.

In this case, first, the mold22is displayed on the display unit36to be smaller than the frame F3, and the mold22displayed gradually becomes greater as the mold22lowers. Thereafter, the mold22on the display becomes greater than the frame F3, and when the mold22lowers further, the mold22on the display becomes greater than the frame F2. Finally, the mold22on the display becomes greater than the frame F1.

As a result, when the operator controls the crane so as to fit the mold22within the smallest carry-in range IR among the displayed carry-in ranges IR greater than the mold22, it is possible to lead the mold22into place between the stationary platen24and the moving platen26without causing any interference with obstacles. Further, displaying the multiple carry-in ranges IR having different sizes corresponding to a plurality of distances enables precise guidance of the mold22through the carry-in route and makes it possible to shorten the time for loading the mold22.

VARIATIONAL EXAMPLES

The above-described embodiment can also be modified as follows.

In the above embodiment, the imaging unit32is provided on the machine base18so that the obstacles, i.e., the stationary platen24, the moving platen26, and the tie bars30can be imaged together with the mold22. In variational example 1, however, the imaging unit32is arranged at a position where the imaging unit32cannot capture the stationary platen24, the moving platen26, and the tie bars30. Here, also in variational example 1, as the above embodiment, the mold22is imaged from the side to which the mold is loaded (negative Z-direction side).

FIGS. 7A and 7Bare views showing an installation example of the imaging unit32in variational example 1,FIG. 7Abeing a diagram when the clamping device is viewed from the front andFIG. 7Bbeing a sectional diagram cut along a plane VIIB-VIIB inFIG. 7A. Here, the same components as those described in the above embodiment are allotted with the same reference numerals, and only the different points will be described.

The imaging unit32is arranged on the upper surface of the stationary platen24. Thereby, the imaging unit32does not pick up the image of the stationary platen24, the moving platen26, and the tie bars30, but can capture images of the mold22carried in by the crane. In this case, it is preferable that the imaging unit32is arranged between the two tie bars30(30a,30cor30b,30d) provided along the Y-direction (seeFIG. 7B).

FIG. 8is a diagram showing a display example of the display unit of variational example 1. As shown inFIG. 8, on the display unit36, the image captured by the imaging unit32is displayed with a frame F. This frame F shows the carry-in range IR. The area surrounded by the frame F is the carry-in range IR.

In this way, even if the obstacles, i.e., the stationary platen24, the moving platen26, and the tie bars30are not imaged, it is possible to guide the mold22through the carry-in route by displaying the image of the mold22together with the carry-in range IR. Therefore, the operator, as watching the image displayed on the display unit36, controls the crane so that the mold22displayed on the display unit36falls within the carry-in range IR, whereby it is possible to lead the mold22in place between the stationary platen24and the moving platen26without causing the mold22to interfere with any obstacles. Further, the time for loading the mold22can be shortened.

Also in variational example 1, the display unit36may simultaneously display multiple carry-in ranges IR each having a size corresponding to one of the predetermined different distances from the imaging unit32. In this manner, even if the obstacles, i.e., the stationary platen24, the moving platen26, and the tie bars30are not imaged, it is possible to exactly guide the mold22through the carry-in route by displaying the carry-in ranges IR corresponding to the multiple distances. As a result, when the operator controls the crane so as to fit the mold22within the smallest carry-in range IR among the displayed carry-in ranges IR greater than the mold22, it is possible to lead the mold22into place between the stationary platen24and the moving platen26without causing any interference with obstacles and shorten the time for loading the mold22.

FIG. 9is a diagram for explaining the configuration of a display system10in variational example 2. Here, the same components as those described in the above embodiment will be allotted with the same reference numerals, and only different points will be described.

The display system10further includes a distance measuring unit40in addition to the imaging unit32, the control unit34, and the display unit36. The distance measuring unit40is a distance measuring sensor that measures the distance. The distance measuring unit40is arranged at a lower position (negative Z-direction side) than the mold22to be carried in and measures a distance Lz to the mold22. The distance measuring unit40may be provided in the imaging unit32. The distance measuring unit40may be arranged between the stationary platen24and the moving platen26. Alternatively, the distance measuring unit40may be provided on the upper surface of the stationary platen24.

The control unit34calculates the size of the carry-in range IR corresponding to the distance Lz to the mold22measured by the distance measuring unit40. At this time, the storage medium in the control unit34may store information indicating the size of the carry-in range IR (hereinafter referred to as the standard carry-in range IRs) corresponding to the predetermined distance from the distance measuring unit40(hereinafter referred to as the standard distance Lzs). Then, the control unit34may calculate the carry-in range IR based on the distance Lz measured by the distance measuring unit40, the standard distance Lzs, and the size of the standard carry-in range IRs.

In brief explanation, the size of the carry-in range IR can be given by the relational expression: the size of the carry-in range IR=(the size of the standard carry-in range IRs)×(the standard distance Lzs)/(the distance Lz). That is, as the measured distance Lz becomes longer compared to the standard distance Lzs, the calculated size of the carry-in range IR becomes smaller relative to the standard carry-in range IRs. The control unit34outputs to the display unit36information representing the carry-in range IR of the calculated size.

The display unit36displays the carry-in range IR based on the information representing the calculated size of the carry-in range IR by the control unit34. Therefore, the display unit36displays the carry-in range IR having a size corresponding to the distance Lz measured by the distance measuring unit40, so that the displayed carry-in range IR changes in size according to the measured distance Lz.

In this way, by displaying the carry-in range IR of the size corresponding to the position of the mold22being carried in (the distance Lz from the distance measuring unit40to the mold22) together with the image of the mold22, it is possible to exactly guide the mold22through the carry-in route. Accordingly, the operator, as watching the image displayed on the display unit36, controls the crane so that the mold22displayed on the display unit36falls within the carry-in range IR, whereby it is possible to lead the mold22in place between the stationary platen24and the moving platen26without causing the mold22to interfere with any obstacle. Further, the time for loading the mold22can be shortened.

FIG. 10is a view showing a configuration of a display system10and a clamping device16of an injection molding machine12provided with the display system10according to variational example 3. Here, the same components as those described in the above embodiment will be allotted with the same reference numerals, and only different points will be described.

The clamping device16includes a toggle mechanism50arranged between the moving platen26and the rear platen28. The toggle mechanism50is a mechanism for moving the moving platen26in the X-direction with respect to the rear platen28. The toggle mechanism50includes a ball screw52, a crosshead54screwed with the ball screw52, and a link member56that connects the crosshead54with the moving platen26and the rear platen28and is extendable in the X-direction.

The ball screw52is kept parallel to the X-direction and attached to the rear platen28. The ball screw52is attached to the rear platen28such that the ball screw52is rotatable but immovable in the axial direction. The crosshead54is screwed with the ball screw52on the positive X-direction side with respect to the rear platen28. As the ball screw52rotates, the crosshead54moves in the X-direction. When the ball screw52rotates in the clockwise direction, the crosshead54moves in the positive X-direction, so that the link member56extends. As a result, the moving platen26moves in the positive X-direction relative to the rear platen28. Conversely, when the ball screw52rotates in the counterclockwise direction, the crosshead54moves in the negative X-direction, so that the link member56contracts. As a result, the moving platen26moves in the negative X-direction relative to the rear platen28.

The rotational force of a clamp opening/closing servomotor58provided in the clamping device16is transmitted to the ball screw52via a power transmission device60. Therefore, when the clamp opening/closing servomotor58rotates in the clockwise direction, the rotational force of the clamp opening/closing servomotor58is transmitted to the ball screw52so that the moving platen26(the moving half22b) moves in the positive X-direction to close the mold22. When the clamp opening/closing servomotor58rotates in the counterclockwise direction, the rotational force of the clamp opening/closing servomotor58is transmitted to the ball screw52so that the moving platen26(moving half22b) moves in the negative X-direction to open the mold22.

It should be noted that the power transmission device60is made up from a pulley60aprovided on the rotational shaft of the clamp opening/closing servomotor58, a pulley60bprovided on the ball screw52on the negative X-direction side with respect to the rear platen28, an endless belt60cwound around the pulleys60aand60b, and others.

Further, a threaded portion62is formed at the end part of each of the four tie bars30on the negative X-direction side, and four tie bar nuts64are screwed respectively to the four threaded portions62. The threaded portion62and the tie bar nut64are located on the negative X-direction side of the rear platen28. The tie bar nut64is supported by the rear platen28so as to be rotatable with respect to the rear platen28.

A mold thickness adjusting servomotor66provided in the clamping device16is a motor that adjusts the distance between the stationary platen24and the moving platen26under the condition in which the crosshead54has moved to the foremost position in the positive X-direction (in a state where the link member56is fully extended). Therefore, when the crosshead54has moved to the foremost position, clamping force acts on the mold22. The distance between the stationary platen24and the moving platen26is determined based on the thickness of the mold22and the clamping force.

More specifically, the mold thickness adjusting servomotor66rotates the four tie bar nuts64via an unillustrated power transmission device. As the tie bar nuts64rotate, the tie bar nuts64move in the X-direction so that the rear platen28, the toggle mechanism50, and the moving platen26integrally move in the X-direction. When the mold thickness adjusting servomotor66rotates in the clockwise direction, the rear platen28, the toggle mechanism50, and the moving platen26move together in the positive X-direction, whereas as the mold thickness adjusting servomotor66rotates in the counterclockwise direction, the rear platen28, the toggle mechanism50, and the moving platen26integrally move in the negative X-direction.

The clamp opening/closing servomotor58and the mold thickness adjusting servomotor66are driven under the control of a control device68of the injection molding machine12. An encoder58afor detecting the rotational position, a rotational rate, and the like is provided in the clamp opening/closing servomotor58, whereas an encoder66afor detecting the rotational position, the rotational speed, and the like is provided in the mold thickness adjusting servomotor66. Based on the detection signals from the encoders58a,66a, the clamp opening/closing servomotor58and the mold thickness adjusting servomotor66are feedback-controlled by the control device68.

The distance (distance in the X-direction) Lx between the stationary platen24and the moving platen26is varied by driving the clamp opening/closing servomotor58(driver). Driving the mold thickness adjusting servomotor66(driver) also varies the distance Lx between the stationary platen24and the moving platen26. Therefore, the size of the mold-transportable area IA (more specifically, the length in the X-direction of the mold-transportable area IA) is changed by the driving of the drivers (the clamp opening/closing servomotor58and the mold thickness adjusting servomotor66).

Thus, the control unit34of the display system10obtains from the control device68information indicating the distance Lx between the stationary platen24and the moving platen26. The information that indicates the distance Lx between the stationary platen24and the moving platen26may be the detection signals from the encoders58aand66aor the rotation amounts of the clamp opening/closing servomotor58and the mold thickness adjusting servomotor66. The information that indicates the distance Lx may be the positional information of the rear platen28moved by the mold thickness adjusting servomotor66and the positional information of the moving platen26moved by the clamp opening/closing servomotor58. Further, the distance Lx between the stationary platen24and the moving platen26may be directly acquired by an unillustrated linear sensor.

The control unit34calculates the length of the carry-in range IR in the X-direction based on the acquired information indicating the distance Lx between the stationary platen24and the moving platen26. At this time, the storage medium in the control unit34may have stored the length of the carry-in range IR in the X-direction (hereinafter referred to as the standard carry-in range IRs) corresponding to the predetermined distance (hereinafter referred to as the standard distance Lxs) between the stationary platen24and the moving platen26. Then, the control unit34may calculate the length of the carry-in range IR in the X-direction based on the acquired distance Lx, the standard distance Lxs, and the length of the standard carry-in range IRs in the X-direction.

Briefly, the length the carry-in range IR in the X-direction can be determined by the relational expression: the length of the carry-in range IR in the X-direction=(the length of the standard carry-in range IRs in the X-direction)×(the distance Lx)/(the standard distance Lxs). That is, as the obtained distance Lx becomes longer compared to the standard distance Lxs, the calculated length of the carry-in range IR in the X-direction becomes greater. The control unit34outputs information representing the carry-in range IR of the calculated size to the display unit36. Here, the length of the carry-in range IR in the Y-direction is constant regardless of the acquired distance Lx.

The display unit36displays the carry-in range IR based on the information indicating the length of the carry-in range IR in the X-direction calculated by the control unit34. Therefore, the display unit36displays the carry-in range IR having a size corresponding to the distance Lx between the stationary platen24and the moving platen26, so that the displayed carry-in range IR changes in size according to the distance Lx.

In this manner, by displaying the carry-in range IR of the size corresponding to the distance Lx between the stationary platen24and the moving platen26together with the image showing the mold22, it is possible to exactly guide the mold22through the carry-in route. Accordingly, the operator, as watching the image displayed on the display unit36, controls the crane so that the mold22displayed on the display unit36falls within the carry-in range IR, whereby it is possible to lead the mold22in place between the stationary platen24and the moving platen26without causing the mold22to interfere with any obstacle. Further, the time for loading the mold22can be shortened.

The imaging unit32and the control unit34may be connected by wires or wirelessly. For example, the control unit34and the display unit36may be configured by a mobile terminal such as a PC tablet or a smartphone, so that the mobile terminal may acquire an image from the imaging unit32wirelessly. Thereby, the crane's operator can keep a mobile terminal near the crane's operator and readily watch the image taken by the imaging unit32on the mobile terminal.

Further, the control unit34and the display unit36may be connected by wires or wirelessly. By connecting the control unit34and the display unit36wirelessly, it is possible to provide the display unit36around the crane's operator so that the operator can readily acquire the image taken by the imaging unit32on the mobile terminal.

Moreover, the control unit34may be a part of the control device68of the injection molding machine. The display unit36may be a display device of an unillustrated injection molding machine connected to the control device68. Thus, an inexpensive system can be realized.

The above variational examples 1 to 4 may be freely combined.

[Technical Ideas Obtained from the Embodiments]

Technical ideas that can be grasped from the above embodiment and variational examples 1 to 5 will be described hereinbelow.

A display system (10) display the state of a mold (22) being transported from above into a space between a stationary platen (24) and a moving platen (26) that moves in a predetermined direction relative to the stationary platen (24) in a clamping device (16). The display system (10) includes: an imaging unit (32) configured to image the mold (22) from below; and a display unit (36) configured to display an image taken by the imaging unit (32) together with a carry-in range (IR) of the mold (22) in order to transport the mold (22) in place between the stationary platen (24) and the moving platen (26).

This configuration makes it possible to help the crane's operator guide the mold (22) along the carry-in route. Therefore, the operator can bring the mold (22) in place between the stationary platen (24) and the moving platen (26) without causing the mold (22) to interfere with obstacles, and shorten the time for loading the mold (22).

The display unit (36) may be configured to display the carry-in range (IR) having a size corresponding to a predetermined distance from the imaging unit (32). Thereby, the operator can bring the mold (22) in place between the stationary platen (24) and the moving platen (26) without causing the mold (22) to interfere with obstacles, and shorten the time for loading the mold (22).

The display unit (36) may be configured to display a plurality of carry-in ranges (IR) each having a size corresponding to one of multiple predetermined different distances from the imaging unit (32). This configuration can help the crane's operator exactly guide the mold (22) through the carry-in route of the mold (22). Therefore, the operator can bring the mold (22) in place between the stationary platen (24) and the moving platen (26) without causing the mold (22) to interfere with obstacles, and shorten the time for loading the mold (22).

The display system (10) may further include a distance measuring unit (40) provided below the mold (22) and configured to measure the distance to the mold (22). The display unit (36) may be configured to display the carry-in range (IR) having a size corresponding to the distance measured by the distance measuring unit (40). This configuration can help the crane's operator exactly transport the mold (22) through the carry-in route of the mold (22). Therefore, the operator can bring the mold (22) in place between the stationary platen (24) and the moving platen (26) without causing the mold (22) to interfere with obstacles, and shorten the time for loading the mold (22).

The distance measuring unit (40) may be provided in the imaging unit (32), on the upper surface of the stationary platen (24), or between the stationary platen (24) and the moving platen (26). Thereby, the distance measuring unit (40) can measure the distance to the mold (22).

The imaging unit (32) may be provided on the upper surface of the stationary platen (24). Even with this configuration, it is possible to show the carry-in route of the mold (22) to the crane's operator. Therefore, the operator can put the mold (22) in place between the stationary platen (24) and the moving platen (26) without causing the mold (22) to interfere with obstacles, and shorten the time for loading the mold (22).

The imaging unit (32) may be provided between and below the stationary platen (24) and the moving platen (26). The imaging unit (32) may be configured to image the mold (22) together with possible obstacles that may interfere with the mold (22), the possible obstacles including the stationary platen (24), the moving platen (26), and tie bars (30) for guiding the moving platen (26) to move relative to the stationary platen (24). This configuration enables the operator to recognize the relative positional relationship between the mold (22) and the obstacles by viewing the image. Therefore, the operator can bring the mold (22) in place between the stationary platen (24) and the moving platen (26) without causing the mold (22) to interfere with obstacles, and shorten the time for loading the mold (22).

The display system (10) may further include a driving unit (58,66) configured to move the moving platen (26) relative to the stationary platen (24) so as to vary the distance between the moving platen (26) and the stationary platen (24). The display unit (36) may be configured to change the size of the carry-in range (IR) to be displayed according to the distance between the moving platen (26) and the stationary platen (24). Thereby, even when the distance between the moving platen (26) and the stationary platen (24) is changed, the operator can bring the mold (22) in place between the stationary platen (24) and the moving platen (26) without causing the mold (22) to interfere with obstacles, and shorten the time for loading the mold (22).

The present invention is not limited in particular to the embodiments described above, and further various modifications are possible without departing from the essence and gist of the present invention.