Roller holding apparatus of printing press

A roller holding apparatus of a printing press comprises roller arms swingably supported by a metal roller, holders swingably supported by the roller arms for holding a rubber roller so as to be detachably mounted on the roller arms, and pressing members provided in the holders for pressing the rubber roller against the metal roller. The roller holding apparatus can perform roller replacement easily and quickly with a simple structure, and can always retain a set nip pressure.

The entire disclosure of Japanese Patent Application No. 2001-382503 filed on Dec. 17, 2001 including specification, claims, drawings and summary is incorporated herein by reference in its entirety.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to a holding apparatus for a roller, such as an ink roller, in a printing press such as a rotary press.

2. Description of the Related Art

In a rotary press or the like, there has so far been a device, as shown, for example, inFIG. 11(see Japanese Unexamined Patent Publication No. 2000-94648), for replacing an ink roller which is located at a position where the ink roller is difficult to replace.

In this replacing device, a lever101is pivotally supported on a shaft of an adjacent ink roller100. An ink roller103, which is present at a position where the ink roller103is difficult to replace, is supported by the lever101via a bearing102. By turning the lever101, the ink roller103, which is located at a position where it is difficult to replace, is moved to a position where it is easy to replace. At this position, the ink roller103is replaced.

In this device, however, an air cylinder104is used for adjusting nip pressure against a plate cylinder and the roller adjacent to the ink roller103located at the position where its replacement is difficult. Thus, a connecting mechanism105for connecting the lever101to the air cylinder104must be provided, making the entire mechanism complicated. Moreover, whenever the ink roller103, located at the position where its replacement is difficult, is moved to the position where its replacement is easy, a screw (not shown) of the connecting mechanism105has to be turned manually and undone. A work load is imposed on an operator, and it takes time to replace the ink roller.

As an automatic nip pressure adjusting mechanism for an adjacent roller, there is, for example, one as shown inFIG. 12(Japanese Utility Model Registration No. 2588289).

In this automatic nip pressure adjusting mechanism, a slot202is provided in an arm201supported on an adjacent roller200, a protuberance205is provided on a holder204of a roller203, and a hole is provided in a front end portion of the protuberance205. The protuberance205of the holder204is inserted through the slot202of the arm201, and a rod207supported by a pin206supported by the arm201is inserted through the hole of the protuberance205of the holder204. A helical compression spring209is provided between the protuberance205of the holder204and a locking nut208of the rod207. Thus, the automatic nip pressure adjusting mechanism is large in the number of the components, high in the cost, and complicated in the mechanism. Provision of this automatic nip pressure adjusting mechanism in the surroundings of the ink roller103located at the aforementioned position, where the replacement of the ink roller103is difficult, presents difficulty in terms of space, and is not acceptable at all.

SUMMARY OF THE INVENTION

The present invention has been accomplished to solve the above-described problems with the earlier technologies. It is the object of the invention to provide a roller holding apparatus of a printing press which can perform roller replacement easily and promptly with a simple structure, and which can always retain a set nip pressure.

According to the present invention, for attaining the above object, there is provided a roller holding apparatus of a printing press, comprising:

a first roller supported rotatably;

an arm supported swingably;

a holder, swingably supported by the arm, for holding a second roller so as to be detachably mounted on the arm; and

a pressing member, provided in the holder, for pressing the second roller against the first roller.

According to this feature, roller replacement can be performed easily and quickly with a simple structure, and a set nip pressure can be always retained.

In the roller holding apparatus of a printing press, the pressing member may urge the second roller toward the first roller by a first elastic member.

In the roller holding apparatus of a printing press, the pressing member may comprise a first depression provided in the holder on a side of the second roller; a first hole provided in the holder and communicating with the first depression; a first pin inserted into the first hole and provided with a contact portion in contact with the second roller; and a first elastic member interposed between the bottom of the first depression and the contact portion of the first pin.

In the roller holding apparatus of a printing press, the pressing member may further comprise pressing force adjusting means for adjusting the pressing force of the pressing member.

In the roller holding apparatus of a printing press, the pressing member having the pressing force adjusting means may comprise a first hole provided in the holder and having a threaded portion provided in the inside thereof; an adjusting screw screwed into the threaded portion of the first hole and having a hole; a first pin inserted into the hole of the adjusting screw and having a contact portion in contact with the second roller; and a first elastic member interposed between the adjusting screw and the contact portion of the first pin.

The roller holding apparatus of a printing press may further comprise a second hole provided in one of the arm and the holder; a second pin provided in the other of the arm and the holder; and a second elastic member for urging the second pin toward the second hole.

The roller holding apparatus of a printing press may further comprise holding means for holding the arm at a replacement position where the second roller is replaced, and at a printing position where the second roller contacts a third roller.

In the roller holding apparatus of a printing press, the holding means may include first and second brackets fixed to a frame of the printing press; depressions provided in the first and second brackets or in the arm; and a fixing pin provided in the arm if the depressions are provided in the first and second brackets, or the fixing pin being provided in the first and second brackets if the depressions are provided in the arm, and the fixing pin being insertable into the depression provided in the first and second brackets or in the arm.

In the roller holding apparatus of a printing press, the holding means may include a stopper member fixed to a frame of the printing press; a stopper portion provided in the arm; and an actuator pivotally supported by the arm.

In the roller holding apparatus of a printing press, the holding means may include a stopper member fixed to a frame of the printing press; a stopper portion provided in the arm; and a second elastic member pivotally supported by the arm.

In the roller holding apparatus of a printing press, the arm may be provided with a handgrip for swinging the arm.

In the roller holding apparatus of a printing press, the arm may be supported so as to be swingable between a printing position where the second roller is in contact with the first roller and a third roller and printing is performed, and a replacement position where the second roller is separated from the third roller and the second roller is replaced.

In the roller holding apparatus of a printing press, the holder may be supported so as to be swingable between a holding position where the second roller is held by the arm, and a release position where the second roller can be replaced from and mounted on the arm, and the holder may be swung to the release position, with the arm being located at the replacement position, whereby the second roller can be replaced.

In the roller holding apparatus of a printing press, the pressing member may, at least, include a spring, and the arm may be located at the printing position, whereby a constant pressure against the first roller and the third roller is imparted to the second roller by the spring.

DETAILED DESCRIPTION OF THE INVENTION

Embodiments of the roller holding apparatus of the printing press according to the present invention will now be described in detail with reference to the accompanying drawings, which in no way limit the invention.

First Embodiment

FIG. 1is a side view of the essential parts of an inking device showing a first embodiment of the present invention.FIG. 2is a developed plan view of the essential parts of the inking device. FIGS.3(a) to3(c) are views illustrating actions of the essential parts of the inking device.FIG. 4is a side view of an inking unit of the inking device.

Of ink rollers2in an inking device (inking unit)1of a rotary press capable of rainbow printing, as shown inFIG. 4, a rubber roller (second roller)2cdisposed between metal rollers (first and third rollers)2aand2bcan be replaced where necessary. The rubber roller2cin the lowest stage at a position, where it is difficult to replace, can be moved by the present roller holding apparatus between a printing position and a replacement/mounting position, as indicated by arrows in the drawing.

A detailed description will be presented by reference toFIGS. 1 and 2. The metal roller2ais rotatably supported between right and left frames3of the inking device1via bearings4. A driving force is transmitted from a drive source (not shown) via gears5joined to the shaft ends of the metal roller2a.

Triangular roller arms6are pivotally (swingably) supported at shaft portions on both sides of a roller body of the metal roller2alocated inwardly of the bearings4. Front portions of the roller arms6are connected by a width determining/reinforcing handgrip7, while rear portions of the roller arms6are connected by a width determining/reinforcing stay8.

A bearing support portion9is provided on the inner surface of an intermediate portion of each of the roller arms6. The rubber roller2cis rotatably supported between the bearing support portions9via bearings10. Right and left holders11, as a pair, each in the shape of a bell crank (to be described later) enable the rubber roller2cto be mounted on and dismounted from the roller arms6, together with the bearings10.

The holder11is pivotally (swingably) supported at one end portion thereof by a pin12. A positioning pin (second pin)13provided in an intermediate portion of the holder11is inserted into and engaged with an engagement hole (second hole)14formed in the roller arm6. By these means, the rubber roller2cis unremovably held by the roller arm6. The positioning pin13is always urged by a compression spring (second elastic member)15in a direction in which the positioning pin13protrudes from the holder11toward the roller arm6.

When, at the replacement/mounting position of the rubber roller2c(see chain lines shown in FIG.1), the holder11is pivoted (swung) clockwise inFIG. 1until it hits an engagement pin (stopper pin)16formed on the roller arm6, the holder11is stably fixed at this position, and the rubber roller2ccan be replaced from and mounted on the roller arm6.

A pressing member17for pressing the rubber roller2cagainst the metal rollers2a,2bvia an elastic member is provided in the other end portion of the holder11. In the illustrated embodiment, the pressing member17comprises a depression (first depression)18provided in the holder11on a side of the rubber roller2c, a hole (first hole)19provided in the holder11and communicating with the depression18, a pin (first pin)20inserted into the hole19and having a contact portion20acontacting the bearing10of the rubber roller2c, and a compression spring (first elastic member)21interposed between the bottom of the depression18and the contact portion20aof the pin20. A stopper20bis provided in the pin20. The stopper20bis designed to prevent the pin20from slipping out of the holder11when the holder11is pivoted (swung) from the position of FIG.3(b) to the position of FIG.3(a).

Thus, at the printing position of the rubber roller2c(see solid lines shown in FIG.1), the bearing10of the rubber roller2cis pressed in the bearing support portion9in a predetermined direction by the compression spring21, whereby the nip pressure of the rubber roller2cagainst the metal rollers2a,2bis always kept constant.

The roller arm6is selectively positioned and fixed by holding means at the printing position and the replacement/mounting position of the rubber roller2c. In the illustrated embodiment, the holding means comprises a printing position fixing bracket22and a replacement/mounting position fixing bracket23secured to each of the right and left frames3, depressions24and25provided in the brackets22and23(or the roller arm6), a fixing pin26provided in the roller arm6(or the brackets22and23) and insertable into the depression24or25, and handle-equipped pivot covers27and28capable of closing the depressions24and25while the fixing pin26is being inserted into the depression24or25.

The roller holding apparatus of the present invention is constructed as described above. Next, its actions will be described with reference to FIGS.3(a) to3(c).

At the printing position of the rubber roller2c, as shown in FIG.3(c), the roller arm6is positioned and fixed at the printing position fixing bracket22via the fixing pin26as stated earlier.

In this state, the rubber roller2cis held by the holder11so as to be unremovable from the roller arm6, and is brought into contact with the metal rollers2aand2bby being elastically urged by the pressing member17provided in the holder11as stated earlier.

Under this urging force, the nip pressure (width), which affects printing quality, is always constant and requires no adjusting operation, even if the roller diameter changes, for example, as a result of thermal expansion.

When the rubber roller2cis to be replaced because of wear or the like, the engagement between the fixing pin26and the printing position fixing bracket22is released, then the handgrip7is gripped and moved to pivot (swing) the roller arm6clockwise about the shaft portion of the metal roller2a, thereby positioning and fixing the roller arm6at the replacement/mounting position fixing bracket23via the fixing pin26, as shown in FIG.3(b).

At this time, the positional relation between the holder11and the roller arm6remains unchanged, so that the rubber roller2cdoes not leave the metal roller2aeven when the roller arm6pivots (swings).

Then, as shown in FIG.3(a), the holder11is pivoted (swung) clockwise about the pin12to make contact with the engaging pin16. At this position, the holder11is fixed stably, as stated previously.

Consequently, the rubber roller2c, together with the bearings10, can be replaced and mounted relative to the roller arm6.

According to the above-described simple structure in which the roller arm6equipped with the holder11requiring no nip pressure adjusting operation is pivoted (swung) about the shaft portion of the metal roller2a, the rubber roller2cis moved from the position where it is difficult to replace, to the position where it is easy to replace. Hence, roller replacement can be performed easily and quickly.

Also, the handles of the pivot covers27and28, and the handgrip7, etc. are incorporated as components, so that no special tools are needed.

In the foregoing embodiment, the rubber roller2cis adapted to roll on the metal roller2a(FIGS.3(b) to3(c)). However, the rubber roller2cneed not roll on the metal roller2a, and may make contact with the metal roller2a(or metal rollers2a,2b) at the position shown in FIG.3(c) (the rotation center of the roller arm may be eccentric with respect to the axis of the metal roller). Moreover, the roller arm6may be free to pivot (swing) relative to the frame3.

Second Embodiment

FIG. 5is a side view of the holder portion showing a second embodiment of the present invention.

This is an embodiment, in which the pressing member17of the holder11in the first embodiment, is provided with pressing force adjusting means for adjusting the pressing force of the pressing member17. In the illustrated embodiment, the pressing member17comprises a hole (first hole)31provided in the holder11and having a threaded portion30formed in the inside thereof; an adjusting screw33screwed into the threaded portion30of the hole31and provided with a hole32; a pin (first pin)34inserted into the hole32of the adjusting screw33and having a contact portion34ain contact with the rubber roller2c; a compression spring (first elastic member)35interposed between the adjusting screw33and the contact portion34aof the pin34; and a locking nut36for preventing the loosening of the adjusting screw33. A stopper34bis provided in the pin34. The stopper34bis designed to prevent the pin34from escaping from the holder11when the holder11is pivoted (swung) from the position of FIG.3(b) to the position of FIG.3(a). Other constructions are the same as in the first embodiment.

According to the present embodiment, the degree to which the adjusting screw33is screwed in is changed, whereby the spring load of the compression spring35is varied. As a result, the pressing force of the pressing member17is changed, whereby the nip pressure of the rubber roller2cagainst the metal rollers2a,2bcan be adjusted arbitrarily.

Third Embodiment

FIG. 6is a side view of the essential parts of an inking device showing a third embodiment of the present invention.FIG. 7is a developed plan view of the essential parts of the inking device.

This is an embodiment, in which the holding means in the first embodiment for selectively positioning and fixing the roller arm6at the printing position and the replacement/mounting position of the rubber roller2c, is composed of a stopper member40fixed on the frame3and positionally adjustable by the degree of screwing-in; a stopper portion41provided in the roller arm6and capable of contacting the stopper member40; and an air cylinder (actuator)42having a piston rod front end pivotally connected to the roller arm6and a cylinder portion pivotally supported by the frame3. Other constructions are the same as in the first embodiment.

According to this embodiment, the air cylinder42is contracted to bring the stopper portion41into contact with the stopper member40, whereby the roller arm6can be held at the printing position of the rubber roller2c(see solid lines shown in FIG.6). On the other hand, the air cylinder42is expanded, whereby the roller arm6can be held at the replacement/mounting position of the rubber roller2c(see chain lines shown in FIG.6). This actuation of the air cylinder42can be performed by remote control.

In the present embodiment, the stopper member40, the stopper portion41, and the air cylinder42constitute the holding means. The holding means holds the roller arm6by the stopper member40, the stopper portion41, and the air cylinder42when the rubber roller2cis located at the printing position. When the rubber roller2cis located at the replacement/mounting position, the holding means holds the roller arm6by the air cylinder42.

In the present embodiment, moreover, the roller arm6is pivoted (swung) by the air cylinder42, but a handgrip may be provided as in the other embodiments. Furthermore, a surface of the roller arm6, which defines the stopper portion41, is brought into contact with the stopper member40. However, a bracket may be mounted on the roller arm6, and this bracket may make contact with the stopper member40.

Fourth Embodiment

FIG. 8is a side view of the essential parts of an inking device showing a fourth embodiment of the present invention.FIG. 9is a developed plan view of the essential parts of the inking device.

This is an embodiment, in which the holding means in the first embodiment for selectively positioning and fixing the roller arm6at the printing position and the replacement/mounting position of the rubber roller2c, is composed of a stopper member50fixed on the frame3and positionally adjustable by the degree of screwing-in; a stopper portion51provided in the roller arm6and capable of contacting the stopper member50; and a roller arm urging/fixing member (third elastic member)53provided with a compression spring52and having an operating end pivotally connected to the roller arm6. Other constructions are the same as in the first embodiment.

According to this embodiment, simply by switching the handgrip7between two positions, the roller arm6is automatically and selectively positioned and fixed at the printing position and the replacement/mounting position of the rubber roller2cunder the spring force of the compression spring52. That is, when the handgrip7is brought to a solid-line position shown inFIG. 8, the stopper portion51is brought into contact with the stopper member50by the spring force of the roller arm urging/fixing member53equipped with the compression spring52, whereby the roller arm6can be held at the printing position of the rubber roller2c(see solid lines shown in FIG.8). On the other hand, the handgrip7is brought to a chain-line position shown inFIG. 8by once contracting the compression spring52during the pivoting (swinging) of the roller arm6. In this case, the roller arm6can be held at the replacement/mounting position (see chain lines shown inFIG. 8) of the rubber roller2cby the spring force of the roller arm urging/fixing member53equipped with the compression spring52. At this replacement/mounting position of the rubber roller2cas well, a stopper (not shown) for confining the roller arm6to this position may be provided in the frame3.

In the present embodiment, the stopper member50, the stopper portion51, and the roller arm urging/fixing member53, equipped with the compression spring52, constitute the holding means. The holding means holds the roller arm6by the stopper member50, the stopper portion51, and the roller arm urging/fixing member53equipped with the compression spring52, when the rubber roller2cis located at the printing position. When the rubber roller2cis located at the replacement/mounting position, the holding means holds the roller arm6by the roller arm urging/fixing member53equipped with the compression spring52.

Fifth Embodiment

FIG. 10is a side view of the essential parts of an inking device showing a fifth embodiment of the present invention.

In this embodiment, the handgrip7in the fourth embodiment is channel-shaped when viewed in a front view. Its right and left end shaft portions60are pivotally supported on the frame3(see FIG.9). A lever61is integrally connected to the shaft portion60. An arcuate link63has one end portion pivotally connected to the front end of the lever61by a pin62, and has the other end portion pivotally connected to the roller arm6by a pin64. When the handgrip7is pivoted from a solid-line position to a chain-line position (or vice versa) shown inFIG. 10, the roller arm6is pivoted (swung) from the printing position of the rubber roller2c(see solid lines shown inFIG. 10) to the replacement/mounting position of the rubber roller2c(see chain lines shown inFIG. 10) (or vice versa) via the lever6and the arcuate link63. Other constructions are the same as in the fourth embodiment.

According to the present embodiment, the same actions and effects as in the fourth embodiment are produced, and the degree of freedom is present in the disposition of the handgrip7. The handgrip7can be disposed easily at a position where it is easy to handle.

While the present invention has been described by the foregoing embodiments, it is to be understood that the invention is not limited thereby, but may be varied in many other ways. Such variations are not to be regarded as a departure from the spirit and scope of the invention, and all such modifications as would be obvious to one skilled in the art are intended to be included within the scope of the appended claims.