Printing plate support device and printing plate removal mounting apparatus as well as methods of operating the same

Description Submit all comments and votes

BACKGROUND OF THE INVENTION

1. Technical Field of the Invention

The present invention relates to a printing plate support device for setting a printing plate at a predetermined position where the printing plate is removably mounted on a plate cylinder of a rotary press and a printing plate removably mounting apparatus as well as methods of operating the device and the apparatus.

2. Description of the Prior Art

In the field of rotary presses, such as a rotary press for newspapers, in which a plurality of printing plates are locked up onto a single plate cylinder, there have been known a variety of structures for mounting a printing plate on the plate cylinder and removing and discharging the printing plate mounted on the plate cylinder therefrom. Such structures are disclosed, for example, in Japanese Examined Patent Publication No. 3-67023 and No. 3-71262 and Japanese Unexamined Patent Publication Nos. 58-188657, 62-74654, 1-176558, 3-184849 and 4-363246.

Of these, the structures described in No. 3-67023 and others, except No. 3-71262, No. 58-188657 and No. 3-184849 above, are each designed to have a displacement mechanism in which a basic body including an arm portion by which a printing plate retaining portion for removably mounting a printing plate on a plate cylinder is provided at an open end is so arranged as to be displaceable in parallel to an axis of the plate cylinder along a rail. The arm portion is provided with a plurality of rotary mechanisms and a linear-drive mechanism such that the afore-mentioned printing plate retaining portion can be displaced at least between a region in which the printing plate is removably mounted on the plate cylinder opposed to the displacing basic body and a portion of the withdrawal that lies in the vicinity of the basic body. Further, the respective mechanism for each of the displacement, rotation and linear-drive needs to be controlled for its individual operation so that they may be operated in their mutually associated mechanism by high-precision control means in order to lock up the printing plate onto the plate cylinder by means of the printing plate retaining portion.

On the other hand, the structures described in No. 3-71262 and No. 58-188657 above are designed each to be provided corresponding to a printing plate lock-up position for a plate cylinder and to eliminate the need to be displaced in parallel to the axis of the plate cylinder and hence to eliminate the need for a displacement mechanism as disclosed in No. 3-67023 and others above. In these structures, however, a printing plate retaining portion that performs the printing plate lock-up operation for a plate cylinder is provided at an open end while an arm portion that comprises a large, a a medium and a small part is utilized. Accordingly, for the printing plate to be locked up onto the plate cylinder, the afore-mentioned rotary mechanisms are respectively operated in a functional association thereof.

Also, the structure described in No. 3-184849 above is so designed that respective printing portions may be stacked one upon another in the direction of their height and that they are disposed outside of a space across which are juxtaposed a pair of rotary presses. Also provided are a displacement mechanism such that the base body including the arm portion by which the printing plate retaining portion that performs the printing plate lock-up operation for the plate cylinder may be displaced along a vertically mounted guide, and a rotary mechanism which can be rotated about the center line of the afore-mentioned guide. The arm portion is provided with a plurality of rotary mechanisms so that the afore-mentioned printing plate retaining portion can be displaced at least between the operating region for removably mounting the printing plate for each plate cylinder in front of the aforementioned space of the two rotary presses as provided. Further, the respective mechanism for each of the displacement and the rotation needs to be controlled for its individual operation so that they may be operated in their mutually associated mechanism by high-precision control means in order to lock up the printing plate onto the plate cylinder by means of the printing plate retaining portion.

At this point, it should be noted that the printing plate lock-up apparatus described in any of the patent publications mentioned above ha unexceptionally been large in the amount of operation for the arm portion or the base body including the arm portion which must be a heavy body, and has so had its positioning accuracy which tends to become relatively low when the printing plate is locked up onto the plate cylinder. In addition, a large energy has been required in it to enable the heavy body to be operated and hence has been a cause that unavoidably increases its running cost. Furthermore, a need has arisen to provide a sufficient measure in order to ensure and maintain the security for an operator in the operating zone and thus has been a cause which increases the manufacturing cost.

Also, in these constructions, since the arm portion in which the printing plate retaining portion is provided is used to removably mount the printing plate onto the plate cylinder, a relatively complex associated operation has been required that resembles a manual operation by an operator. This has necessitated a complicated mechanism and a highly efficient control means, and accordingly has brought about a cause that again increases the manufacturing cost. Also, for a constantly stable operation to be obtained, a relatively frequent maintenance task has been required, thus, here again, pushing up the running cost.

In addition, a relatively large amount of time has been required to engage in the printing plate lock-up stage according to this relatively complex associated operation.

Moreover, in such a printing plate lock-up apparatus, since the printing plates must be taken one by one from a stock portion for them for their lock-up operation onto the plate cylinder, much time has been expended to lock them up onto the single plate cylinder. Hence, many contrivances have been required in order to enhance the operability of a rotary press machine.

SUMMARY OF THE INVENTION

With the foregoing prior-art problems taken into account, it is an important object of the present invention to simplify and to make lighter the operating mechanism of the conventional printing plate removably mounting apparatus, as well as to simplify its operation and to make its control easier.

It is another important object of the present invention to reduce the amount of operations involved in the conventional printing plate removably mounting apparatus.

It is a further important object of the present invention to enhance the positioning accuracy for such an apparatus when a printing plate is locked up onto a plate cylinder.

It is still a further object of the present invention to enable a predetermined positioning to be accomplished corresponding also to a variation in displacement of the plate cylinder in its axial direction.

It is yet a further object of the present invention to enhance the operability of a rotary press machine with a reduced manufacturing cost and a decreased with a reduced manufacturing cost and a decreased running cost and yet with a reduced time required for removably mounting a printing plate onto a plate cylinder.

It is an important object of the present invention to provide an improved printing plate support devise whereby the afore-mentioned conventional problems in the art of a rotary press machine can be obviated.

It is another important object of the present invention to provide an improved printing plate removably mounting apparatus whereby the afore-mentioned conventional problems in the art of a rotary press machine can be obviated.

It is a further important object of the present invention to provide highly efficient methods of operating the devise and the apparatus which are mentioned above.

In accordance with the present invention, there is provided, in a first aspect thereof, in an apparatus for locking up a printing plate in a rotary press having a plate cylinder which is displaceable in its axial direction, is capable of stopping in a predetermined phase of rotation and is provided on its periphery and in parallel to its axis with a printing plate lock-up means, in which the said printing plate is formed with a lock-up hook portion capable of being hooked on and off the printing plate lock-up means, a device for supporting the printing plate comprises:

a printing plate receiving means which is located at a position spaced from the said periphery of the said plate cylinder by a predetermined distance and is formed along the said plate cylinder with a reference site for defining the said lock-up hook portion of the said printing plate in parallel to the axis of the said plate cylinder and, when driven, is displaceable in parallel to the said axis of the plate cylinder;

a receiving position determining means which is so disposed as to be engageable with a positioning engagement portion that is provided at a predetermined position of the said lock-up hook portion of the printing plate mounted onto the said printing plate receiving means for positioning the said printing plate at a predetermined portion of the said printing plate receiving means; and

a stopping position determining means which is disposed at a side portion of the said printing plate receiving means, when driven is displaceable between a position that is opposed to a side end surface of the said plate cylinder and a position that is otherwise, and is adapted to abut on the said side end surface of the plate cylinder according to a displacement of the said printing plate receiving means for stopping the printing plate receiving means at a preselected position relative to the said plate cylinder.

The present invention also provides, in a second aspect thereof, in a rotary press adapted to lock up a printing plate and having a plate cylinder that is displaceable in an axial direction, is rotatable in both a normal drive and a reverse drive, is capable of being stopped in a predetermined phase of rotation, and is formed on its periphery and in parallel to its axis with a printing plate lock-up means, in which the said printing plate being formed with a plurality of lock-up hook portions capable of being hooked on and off the said printing plate lock-up means, and apparatus for removably mounting the printing plate on the plate cylinder comprises:

a printing plate support means disposed at a position along the said plating cylinder and spaced from a periphery thereof by a predetermined distance for supporting the said printing plate in a predetermined positional relationship with the said plate cylinder such that a said printing plate lock-up hook portion may lie in parallel to the axis of the said plate cylinder and be matched with an axial displacement of the said plate cylinder while mounting the said printing plate on the said plate cylinder in such a manner that the printing plate when detached therefrom can be guided towards an outlet direction;

a printing plate displacement means which is disposed in the vicinity of the said printing plate supported on the said printing plate support means and is capable of retaining the said printing plate supported by the said printing plate support means for mounting the said printing plate so as to freely advance at least one of the said lock-up hook portions so that the said printing plate can be fed out towards the said plate cylinder in accordance with a surface generally in contact with the said periphery of the plate cylinder;

a printing plate press means disposed in the vicinity and in front of the periphery of the said plate cylinder for being displaced in and out of contact with the said periphery of the plate cylinder, displacing a said printing plate lock-up hook portion towards the said printing plate lock-up means for the said plate cylinder and pressing the said printing plate against the said periphery of the plate cylinder to mount the said printing plate so as to be capable of wound round the said plate cylinder with a rotation thereof; and

a printing plate lock-up operating means disposed in the vicinity of said printing plate lock-up means of the said plate cylinder at a stoppage thereof in the predetermined phase of rotation for operating the said printing plate lock-up means of the said plate cylinder that is stopped in the said phase of rotation.

The said printing plate support means in the printing plate removably mounting apparatus in accordance with the present invention may also preferably comprise:

a printing plate receiving means which is located at a position spaced from the said periphery of the said plate cylinder by a predetermined distance and is forced along the said plate cylinder with a reference site for defining the said lock-up hook portion of the said printing plate in parallel to the axis of the said plate cylinder and, when driven, is displaceable in parallel to the said axis of the plate cylinder;

a receiving position determining means which is so disposed as to be engageable with a positioning engagement portion that is provided at a predetermined position of the said lock-up hook portion of the printing plate mounted on the said printing plate receiving means for positioning the said printing plate at a predetermined position of the said printing plate receiving means; and

a stopping position determining means which is disposed at a side portion of the said printing plate receiving means, when driven is displaceable between a position that is opposed to a side end surface of the said plate cylinder and a position that is otherwise, and is adapted to abut on the said side end surface of the plate cylinder according to a displacement of the said printing plate receiving means for stopping the printing plate receiving means at a preselected position relative to the said plate cylinder.

The present invention also provides in a further aspect thereof, a method of attaching a printing plate onto a plate cylinder in a rotary press having a printing plate lock-up means, a printing plate lock-up operating means, a printing plate support means, a printing plate press means, a printing plate displacement means, a receiving position determining means and a stop position determining means, which method comprises the steps of:

(a) providing the printing plate with a pair of lock-up hook portions and a positioning engagement portion;

(b) providing the said printing plate lock-up means with a hook member and a groove;

(c) providing the printing plate support means with a printing plate support bar;

(d) providing the said stop position determining means with a stopper member;

(e) providing the said printing plate press means with a roller member;

(f) providing the said printing plate displacement means with a plurality of suckers and a sucker support stay;

(g) rotating the said plate cylinder and stopping its rotation in a predetermined phase of rotation;

(h) hooking one of the said lock-up hook portions on the said printing plate support bar at a reference site while engaging the said positioning engagement portion with the said receiving position determining means corresponding to a right-hand side portion or a left-hand side portion of the said plate cylinder so as to mount the said printing plate on the said printing plate support means;

(i) displacing the said printing plate support bar in parallel to an axis of the said cylinder while displacing the said stop position determining means, and positioning, relative to the said plate cylinder, the said printing plate mounted on the said printing plate support means when the said stopper member is brought into contact with a side end surface of the said plate cylinder;

(j) attracting and retaining the said printing plate by means of the said suckers, displacing the said sucker support stay to a side of the said plate cylinder so as to displace and feed out the said printing plate, placing the said one lock-up portion in front of the said groove, and returning the said stop position determining means to an initial state thereof;

(k) actuating a pressing operation of the said roller member and a withdrawal action for the printing plate by the said printing plate displacement means to cause the said one lock-up hook portion to be hooked on one edge of the said groove, and returning the said printing plate displacement means to an initial state thereof;

(l) regularly rotating the said plate cylinder with the said printing plate pressed against a periphery thereof by the said roller member and displacing, along with the rotation of said plate cylinder, the said one lock-up rotation hooked on the said one edge of the groove to cause the said printing plate to be wound round the said plate cylinder;

(m) stopping the said plate cylinder for each one revolution thereof while continuingly pressing a region of the other of the said lock-up hook portions with the said printing plate press means;

(n) operating the printing plate lock-up operating means to operate the said printing plate lock-up means, and displacing the said other lock-up hook portion by means of the said hook member into a phase in which when it is thrusted into the said groove, there may arise no interference therewith;

(o) thrusting the said other lock-up portion into the said groove by means of the said roller member, displacing the said hook member by means of the said printing plate lock-up operating means, and hooking the said other lock-up hook portion with the said hook member; and

(p) returning the said printing plate press means and the said printing plate lock-up operating means to their respective initial states.

The present invention further provides, in another aspect thereof, a method of detaching a printing plate from a plate cylinder in a rotary press having a printing plate lock-up means, a printing plate lock-up operating means, a printing plate press means and a printing plate support means, which method comprises the steps of:

(a) providing the printing plate with a pair of lock-up hook portions;

(b) providing the said printing plate lock-up means with a hook member and a groove;

(c) providing the said printing plate support means with a printing plate support bar;

(d) providing the said printing plate press means with a roller member;

(e) rotating the said plate cylinder and stopping its rotation in a predetermined phase of rotation;

(f) pressing, with the said roller member, a region of a second of the said lock-up hook portions of the said printing plate that is locked up onto the said plate cylinder;

(g) operating the said printing plate lock-up operating means to operate the said printing plate lock-up means so as to release a hooking of the said second lock-up hook portion with the said hook member, and causing the said second lock-up hook portion to be projected out from the said groove by an elasticity of the said printing plate;

(h) thereafter, returning, with the said printing plate lock-up operating means, the said printing plate lock-up means to an initial state thereof while returning the said printing plate lock-up operating means itself to an initial state thereof;

(i) reversely rotating the said plate cylinder to cause the said printing plate to be gradually removed away from a periphery of the said plate cylinder, and causing the said second lock-up hook portion which is leading to arrive at the said printing plate support bar and to be guided into an outlet side by the said printing plate support bar;

(j) concurrently with the step (i), continuingly pressing, with the said roller member, the said printing plate brought about against the said periphery of the plate cylinder, and thereafter, returning the said roller member to an initial state thereof;

(k) after the said plate cylinder is further reversely rotated to exceed its one revolution, releasing a first of the said lock-up hook portions from one edge of the said groove while a phase of rotation is being reached in which the said printing plate lock-up means lies below the said printing plate support bar; and

(l) after the said phase of rotation is reached in which the said first lock-up hook portion is release from the one edge of the said groove, stopping the reverse rotation of the said plate cylinder when it reaches a suitable phase of rotation.

The present invention still further provides in yet another aspect thereof, a method of operating a printing plate removably mounting apparatus with a plate cylinder in a rotary press having a printing plate lock-up means, a printing plate lock-up operating means, a printing plate support means, a printing plate press means, a printing plate displacement means, a receiving position determining means and a stop position determining means, which method comprises the steps of:

(a) providing a printing plate with a a pair of lock-up hook portions and a positioning engagement portion;

(b) providing the said printing plate lock-up means with a hook member and a groove;

(c) providing the printing plate support means with a printing plate support bar;

(d) providing the said stop position determining means with a stopper member;

(e) providing the said printing plate press means with a roller member;

(f) providing the said printing plate displacement means with a plurality of suckers and a sucker support stay;

(g) rotating the said plate cylinder and stopping its rotation in a predetermined phase of rotation;

(h) hooking a first of the said lock-up hook portions on the said printing plate support bar at a reference site wile engaging the said positioning engagement portion with the said receiving position determining means corresponding to a right-hand side portion or a left-hand side portion of the said plate cylinder so as to mount the said printing plate on the said printing plate support means;

(i) displacing the said printing plate support bar in parallel to an axis of the said cylinder while displacing the said stop position determining means, and positioning, relative to the said plate cylinder, the said printing plate mounted on the said printing plate support means when the said stopper member is brought into contact with a side end surface of the said plate cylinder;

(j) attracting and retaining the said printing plate by means of the said suckers, displacing the said sucker support stay to a side of the said plate cylinder so as to displace and feed out the said printing plate, placing the said one lock-up portion in front of the said groove, and returning the said stop position determining means to an initial state thereof;

(k) actuating a pressing operation of the said roller member and a withdrawal action for the printing plate by the said printing plate displacement means to cause the said first lock-up hook portion to be hooked on one edge of the said groove, and returning the said printing plate displacement means to an initial state thereof;

(l) regularly rotating the said plate cylinder with the said printing plate pressed against a periphery thereof by the said roller member and displacing, along with the rotation of said plate cylinder, the said first lock-up hook portion hooked on the said one edge of the groove to cause the said printing plate to be wound round the said plate cylinder;

(m) stopping the said plate cylinder for each one revolution thereof while continuingly pressing a region of a second of the said lock-up hook portions with the said printing plate press means;

(n) operating the printing plate lock-up operating means to operate the said printing plate lock-up means, and displacing the said other lock-up hook portion by means of the said hook member into a phase in which when it is thrusted into the said groove, there may arise no interference therewith;

(o) thrusting the said second lock-up portion into the said groove by means of the said roller member, displacing the said hook member by means of the said printing plate lock-up operating means, and hooking the said second lock-up hook portion with the said hook member;

(p) returning the said printing plate press means and the said printing plate lock-up operating means to their respective initial state;

(q) rotating the said plate cylinder and stopping its rotation in a predetermined phase of rotation;

(r) pressing, with the said roller member, a region of the said second lock-up hook portion of the said printing plate that is locked up onto the said plate cylinder;

(s) operating the said printing plate lock-up operating means to operate the said printing plate lock-up means so as to release a hooking of the said second lock-up hook portion with the said hook member, and causing the said second lock-up hook portion to be projected out from the said groove by an elasticity of the said printing plate;

(t) thereafter, returning, with the said printing plate lock-up operating means, the said printing plate lock-up means to an initial state thereof while returning the said printing plate lock-up operating means itself to an initial state thereof;

(u) reversely rotating the said plate cylinder to cause the said printing plate to be gradually removed away from a periphery of the said plate cylinder, and causing the said second lock-up hook portion which is leading to arrive at the said printing plate support bar and to be guided into an outlet side by the said printing plate support bar;

(v) concurrently with the step (u), continuingly pressing, with the said roller member, the said printing plate brought about against the said periphery of the plate cylinder, and thereafter, returning the said roller member to an initial state thereof;

(w) after the said plate cylinder is further reversely rotated to exceed its one revolution, releasing the said first lock-up hook portion of the printing plate from the said one edge of the groove while a phase of rotation is being reached in which the said printing plate lock-up means lies below the said printing plate support bar; and

(x) after the said phase of rotation is reached in which the said first lock-up hook portion is released from the one edge of the said groove, stopping the reverse rotation of the said plate cylinder when it reaches a suitable phase of rotation.

According to the printing plate support device of the foregoing construction, first of all, i.e. for the reason that by means of the reference site for defining the lock-up hook portion in parallel to the axis of the plate cylinder, the lock-up hook portion may be defined in parallel to the axis of the plate cylinder and the positioning engagement portion disposed at a predetermined position of the lock-up hook portion may be engaged with the receiving position determining means disposed on the printing plate catching means, the printing plate may be located at a predetermined position of the printing plate receiving means. The printing plate may then be mounted on the printing plate receiving means by a suitable means or by way of a manual operation.

Subsequently, the printing plate receiving means may be driven and remain displaced until the stop position determining means disposed in parallel to the axis of the plate cylinder and at the side portion of the printing plate receiving means reaches the maximum axially displaceable position at which the side end portion of the plate cylinder may be turned up aside.

It follows that the stop position determining means may be driven and displaced to the position which is opposed to the side end surface of the plate cylinder.

Further, the printing plate receiving means may be driven and remain displaced until it is brought into contact with the side end surface which may be in parallel to the axis of the plate cylinder and with which the stop position determining means may be juxtaposed. As a result of its contact with the side end surface of the plate cylinder with which the stop position determining means is juxtaposed, the printing plate receiving means may be stopped, holding its predetermined positional relationship with the plate cylinder.

Also, according to the printing plate removably mounting apparatus of the foregoing construction, a mention may first be made of the printing plate lock-up. The plate cylinder may be stopped in a predetermined phase of rotation, that is, in a phase in which the printing plate lock-up means becomes, as will be described hereinafter, capable of being hooked off with one of the lock-up hook portions for the printing plate that is being fed out while the printing plate may be supported on the printing plate support means by defining its lock-up hook portion in parallel to the axis of the plate cylinder, locating it at a predetermined receiving position, and then mounting it on the printing plate support means by using a suitable means or by way of a manual operation.

When this printing plate removably mounting apparatus is equipped with the printing plate support means of the foregoing construction as a printing plate support means used therein, the plate cylinder may be stopped in a phase as described above while the printing plate may be supported on the printing plate support means as a result of the fact that the lock-up hook portion is defined in parallel to the axis of the plate cylinder by the reference site adapted to define the lock-up hook portion in parallel to the axis of the plate cylinder and that the position determining engagement portion disposed at a predetermined position of a said lock-up hook portion is engaged with the receiving position determining means disposed on the printing plate receiving means so as to be located at a predetermined position of the printing plate receiving means and is then mounted on the printing plate support means by a suitable means or by way of a manual operation.

Subsequent to the above, the printing plate displacement means may hold the printing plate supported on the printing plate support means and may then freely advance at least one of the hock-up hook portions so as to feed out the printing plate by a predetermined amount towards the plate cylinder, that is, until the one of the lock-up hook portions is brought into a point of its opposition to the printing plate lock-up means for the plate cylinder that remains stopped with an aforementioned predetermined phase of rotation.

Subsequently, one of the lock-up hook portion for the printing plate may be pressed by the printing plate press means towards the printing plate lock-up means and may then be hooked on the printing plate lock-up means by an interaction between a withdrawal operation by way of the printing plate displacement means and a displacement operation towards a suitable direction by way of the printing plate press means.

Still subsequently, a suitable position of the printing plate may be pressed by the printing plate press means against the peripheral surface of the plate cylinder to cause the printing plate to be wound round the plate cylinder by rotating the plate cylinder in the normal direction. Also, the printing plate displacement means may be returned to its original position. And, the plate cylinder having the printing plate wound thereround may then be stopped in a predetermined phase of rotation, that is, in a phase in which the other of the lock-up hook portions for the printing plate can be opposed to the printing plate lock-up means adapted to hook the same.

When the plate cylinder is stopped, the printing plate lock-up means adapted to hook the other lock-up hook portion for the printing plate may be operated into a preparatory hooking state in which the other lock-up hook portion can be hooked while the printing plate press means may be displaced to press the other lock-up hook portion against the printing plate lock-up means. When this pressing operation is completed, the printing plate lock-up operating means may, reversely to the above, be adapted to operate the printing plate lock-up means that lies in a hooking preparatory state, to hook the other lock-up hook portion for the printing plate, thereby locking up the printing plate onto the plate cylinder.

When the printing plate is to be detached, the plate cylinder may be stopped in a predetermined phase of rotation, that is, in a phase in which the printing plate lock-up means that hooks the other lock-up hook portion of the printing plate can be operated by the printing plate lock-up operating means, for example, in a phase which is the same as that in which the other lock-up hook portion of the printing plate is hooked by the printing plate lock-up means in the afore-mentioned lock-up operation for the printing plate.

Subsequently, the printing plate press means may press those sites which are in the vicinity of the other lock-up hook portion of the printing plate against the peripheral surface of the plate cylinder while the printing plate lock-up means may be operated by the printing plate lock-up operating means into a hooking preparatory state in the afore-mentioned lock-up for the printing plate.

When this takes place, the hooking state between the operated printing plate lock-up means and the other lock-up hook portion may be released and the printing plate may be detached from the peripheral surface of the plate cylinder by the fact that the side in which the other lock-up hook portion lies may leap up rather than the site which has been pressed by the printing plate press means, due to a resilient action of the printing plate.

In this sate, the plate cylinder may be reversely rotated to gradually detach the printing plate from the peripheral surface of the plate cylinder. The printing plate detached from the peripheral surface as the other lock-up hook portion reaches the printing plate support means may be moved away from the plate cylinder by the upper end of the printing plate support means with its leading end constituted by that other lock-up hook portion, and thus be guided into an outlet direction.

Further, the reversed rotation of the plate cylinder may be continued so that the printing plate lock-up means on which one of the lock-up hook portions is hooked may surpass the stopping phase of the plate cylinder in the afore-mentioned lock-up for the printing plate. The hooking state between the one of the lock-up hook portions and the printing plate lock-up means may thereby be released to complete the detachment of the printing plate from the plate cylinder. It is also preferable that in a suitable phase of the reversed rotation of the plate cylinder, the printing plate press means should be detached from the printing plate to release the printing plate from its press onto the peripheral surface of the plate cylinder.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will be understood more fully from the detailed description given hereinafter and from the accompanying drawings of certain preferred embodiments of the present invention, which, however, should not be taken to be limitative to the invention, but are for an explanation and understanding thereof only.

In the drawings:

FIG. 1A is a cross-sectional view diagrammatically illustrating the entire construction of a certain embodiment according to present invention;

FIG. 1B is a perspective view diagrammatically illustrating a printing plate that may be used in the embodiment as shown in FIG. 1A and according to the present invention;

FIG. 1C is an enlarged cross-sectional view diagrammatically illustrating a portion of the embodiment as shown by the arrow A in FIG. 1A;

FIG. 2 is a diagrammatic view illustrating a portion of the embodiment as seen in the direction shown by the arrow B in FIG. 1A;

FIG. 3 is a diagrammatic view illustrating a portion of the embodiment as seen in the direction shown by the arrow C in FIG. 1A;

FIG. 4 is a diagrammatic view illustrating a portion of the embodiment as seen in the direction shown by the arrow D in FIG. 1A;

FIG. 5 is a diagrammatic view illustrating a portion of the embodiment as taken at E--E and as seen in the direction of the arrows in FIG. 4;

FIG. 6 is a diagrammatic view of a portion of the embodiment as taken at G--G and as seen in the direction shown by the arrows in FIGS. 2 and 3;

FIG. 7 is a diagrammatic view illustrating a portion of the embodiment as seen in the direction shown by the arrow D in FIG. 1A with a positional relationship with a plate cylinder between the frames at both sides;

FIGS. 8A through 8C are a flow chart illustrating a lock-up operation for mounting the printing plate onto the plate cylinder in the embodiment shown in FIGS. 1A through 1C;

FIGS. 9A and 9B are a flow chart illustrating a removal operation for detaching the printing plate from the plate cylinder in the embodiment shown in FIGS. 1A through 1C;

FIG. 10 is an operation diagrammatic view illustrating a state in which the plate cylinder is supported by a printing plate support bar which is positioned relative to the plate cylinder in the axial direction;

FIG. 11 is an operational diagrammatic view illustrating a state in which the printing plate is displaced to the side of the plate cylinder;

FIG. 12 is an operational diagrammatic view illustrating a state in which the printing plate is wound round the plate cylinder;

FIG. 13 is an operational diagrammatic view illustrating a printing plate lock-up operation of a printing plate lock-up means;

FIG. 14 is an operational diagrammatic view illustrating another printing plate lock-up operation of a printing plate lock-up means;

FIG. 15 is an operational diagrammatic view illustrating a state in which a printing plate lock-up operation is completed;

FIG. 16 is an operational diagrammatic view illustrating a printing plate removal operation for a printing plate lock-up means;

FIG. 17 is an operational diagrammatic view illustrating a printing plate removal operation for detaching a printing plate from a plate cylinder; and

FIG. 18 is an operational diagrammatic view illustrating another printing plate removal operation for detaching a printing plate from a plate cylinder.

DESCRIPTION OF THE PREFERRED EMBODIMENT

The present invention will be discussed hereinafter for a certain preferred embodiment and embodiments thereof with reference to the accompanying drawings. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention. It would be obvious, however, to a person skilled in the art that the present invention may be practiced without those specific details. In other instances, a well-known structure is not shown in detail in order not to unnecessarily obscure the essences of the present invention.

While the present invention relates in part to a printing plate lock-up device and a printing plate removably mounting apparatus, it should also be noted that since the printing plate support device is intended to correspond to the printing plate support means in the printing plate removably mounting apparatus, the explanation of the printing plate support means in the printing plate removably mounting apparatus hereinbelow also represents an explanation of the printing plate support device.

Now, referring to FIGS. 1A through 7, there is shown a printing plate removably mounting apparatus that embodies one aspect of the present invention. The printing plate removably mounting apparatus shown is provided for each plate cylinder PC in a rotary press and comprises a printing plate support means 1, a printing plate displacement means 2, a printing plate press means 3 and a printing plate lock-up operating means 4.

In the embodiment shown in FIG. 1A, the printing plate support means 1 is adapted to support a printing plate PP and is provided with a printing plate receiving means 11 for supporting the printing plate PP at a position which corresponds to the plate cylinder PC so that one PP1 of lock-up hook portions PP1 and PP2 (see FIG. 1B) foldedly formed in parallel to each other at a pair of sides (e.g. an upper side and a lower side), respectively, of the printing plate PP may be arranged to be in parallel to the axis of the plate cylinder PC (see FIGS. 1A, 4, 5 and 7).

The printing plate receiving means 11 is mounted to a pair of sub-frame SF and SF which are secured to a pair of frames F and F, respectively, at both sides of a rotary press. This is shown with respect to the frame at one side in each of the Figures except FIG. 7.

More specifically, the sub-frames SF and SF have mounted respectively thereon, via a pair of brackets 11a and 11a, a pair of guide rails 11b and 11b which extend in parallel to each other and to the axis of the plate cylinder PC and which, in turn, have respectively secured thereto a pair of displacement members 11c and 11c that are displaced along the guide rails 11b and 11b, respectively. Secured to these displacement members 11c and 11c is a printing plate support bar 11d which is displaced, integrally with the displacement members 11c and 11c, along the guide rails 11b and 11b.

Also, secured to either one of the sub-frames SF at a site that is opposed to a side end of one displacement member 1c is a hydraulic cylinder 11e which is so operated that its piston rod may be displaced in the directions as shown by the arrows .alpha. and .alpha.' in FIGS. 4 and 7, respectively. The piston rod of this hydraulic cylinder 11e is connected to one side end of the afore-mentioned one displacement member 11c.

Further, at a position at which the aforementioned printing plate support bar 11d is juxtaposed with the plate cylinder PC there is arranged an edge-shaped reference site 11f on which the one lock-up hook portion PP1 is capable of being hooked for defining the one lock-up hook portion PP1 to be in parallel to the axis of the plate cylinder PC when it is so hooked. In addition, there is arranged at a suitable position a sensing means (not shown) for detecting a printing plate PP as supported by the printing plate support bar 11d.

On the other hand, the printing plate receiving means 11 is provided with a receiving position determining means 12 that is designed to define a receiving position on the printing plate receiving means 11 for a printing plate PP as mounted thereon.

More specifically, the reference site 11f of the afore-mentioned printing plate receiving bar 11d is formed with the receiving position determining means 12 with which a recessed positioning portion PP3 (see FIG. 1B) formed at a predetermined position of the one lock-up hook portion PP1 for a printing plate PP is engaged for positioning the printing plate PP at a predetermined site of the printing plate support bar 11d.

Furthermore, the printing plate receiving means 11 on the other hand is provided with a stop position determining means 13 (see FIG. 5) that is deigned to stop the printing plate receiving means 11 when it has a predetermined positional relationship with the plate cylinder PC in accordance with a displacement of the plate cylinder PC in its axial direction.

More specifically, the end portion of a site of the afore-mentioned printing plate support bar 11d in front of the periphery of the plate cylinder PC has secured thereto a rotary actuator 13a whose output shaft is rotated by a predetermined angle in the directions as shown by the arrows .beta. and .beta.' in FIG. 1A, respectively, and a bearing block 13c which supports an intermediate shaft 13b so that the latter may have a common center to the output shaft of the rotary actuator 13a.

Also, one end of the afore-mentioned intermediate shaft 13b is connected to the output shaft of the rotary actuator 13a whereas its other end is connected to one end of a stopper arm 13d whose other end is threadedly coupled to a stopper member 13c so that it may be adjustably displaceable in parallel to the axis of the plate cylinder PC.

Accordingly, by operating the rotary actuator 13a, the intermediate shaft 13b, the stopper arm, 13d and the stopper member 13e will be integrally operated so that they may be displaced between a region in which they are opposed to the peripheral surface of the plate cylinder PC and a region in which they are otherwise.

As shown in FIG. 7, when the plate cylinder herein is constituted by the plate cylinder PC whose right-hand side portion PC1 and left-hand side portion PC2 are separately displaceable about their center in their axial directions, there are provided a pair of the stop position determining means 13 and 13 at both the end portions of the afore-mentioned printing plate support bar 11d, respectively. Then, the site at which the plate cylinder PC is supported is detected by the sensing means not shown and a particular operating one of the pair of the stop position determining means 13 is selected in conjunction with the direction of the operation of the piston rod of the afore-mentioned hydraulic cylinder 11e determined in accordance with a particular result of the detection. See FIGS. 1A, 1B, 4, 5 and 7.

The printing plate displacement means 2 in the embodiment shown in FIG. 1A is designed to attract and retain, upwardly of th