JP3330188B2 - Base paper clamp device for printing equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a stencil clamping device for a printing apparatus, and more particularly, to a stencil clamping device for clamping a stencil sheet on an outer peripheral surface of a rotationally driven plate cylinder in a stencil printing apparatus or the like.

[0002]

2. Description of the Related Art As a stencil clamping device for attaching a thin stencil sheet such as stencil paper to the outer peripheral surface of a plate cylinder of a rotary stencil printing apparatus, the stencil paper is mounted on the outer peripheral surface of the plate cylinder along one generatrix of the plate cylinder. A clamp plate mounted to be rotatable approximately 180 degrees between a base paper clamp position and a base paper unclamping position about an axis extending along the axis extending between the base plate and the outer peripheral surface of the plate cylinder at the base paper clamp position. A stencil clamping device for clamping a stencil with a stencil in between has already been proposed, which is disclosed, for example, in Japanese Utility Model Publication No. 1-26463.

[0003] In the above-described base paper clamping apparatus, the rotation of the clamp plate between the base paper clamp position and the base paper unclamping position is performed by a clamp drive gear provided on a pivot of the clamp plate and a drive gear provided on the output shaft. The drive gear is movable between an engagement position where the drive gear meshes with the clamp drive gear and a release position where the drive gear is separated from the engagement with the clamp drive gear and allows the plate cylinder to rotate freely. Using a motor movably mounted on the main body side of the stencil printing machine by the motor mount, the motor itself is moved to the meshing position together with the motor mount, and the drive gear meshes with the clamp drive gear, and the gear To fix the plate cylinder so that the plate cylinder cannot be rotated by capturing the pivot by a locking member provided on the motor mount so that a reaction force against rotation can be obtained. Ri has done to.

[0004]

In the above-described base paper clamp apparatus, a solenoid device is separately required as an actuator for moving the motor between the meshing position and the release position. Since the output required for maintaining the meshing relationship between the drive gear and the clamp drive gear under rotation is required, the output is relatively large.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems in the conventional stencil clamping device of a printing apparatus, and does not require a large-sized solenoid device. It is an object of the present invention to provide a base paper clamping device for a printing device that performs a simple clamping and unclamping operation.

[0006]

SUMMARY OF THE INVENTION According to the present invention, there is provided a base paper clamping apparatus for a printing apparatus for clamping a base paper on an outer peripheral surface of a rotationally driven plate cylinder. A clamp member that is rotatably displaceable and that can be moved between a clamp position that sandwiches and locks the base paper between the outer peripheral surface of the plate cylinder and a release position that releases the lock of the base paper, and is attached to the pivot. Clamp driving gear, a location pin attached to the plate cylinder, a sector gear that is rotatably provided on the main body side of the printing apparatus and selectively meshes with the clamp driving gear, and that is movable to the main body side of the printing apparatus. A locking member provided to selectively capture and engage the location pin to lock the plate cylinder at a predetermined rotation position; and a drive shaft system identical to the sector gear with the sector gear having a predetermined phase relationship. A cam that is mounted and drives the locking member to catch and engage the location pin prior to the sector gear meshing with the clamp drive gear due to rotation of the drive shaft system; and And a rotary drive actuator for rotary driving the system.

[0007]

According to the above construction, the drive shaft system is rotationally driven by the rotary drive actuator, so that the sector gear and the cam rotate together, and the sector gear engages with the clamp drive gear prior to engagement. The stop member catches and engages the location pin to prevent the plate cylinder from rotating, that is, the plate cylinder is fixed. From this state, the drive shaft system is continuously driven to rotate by the rotation drive actuator, so that the sector gear meshes with the clamp drive gear, and the gear mesh drives the pivot to rotate the clamp member between the clamp position and the release position. Rotational displacement.

[0008]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram of an embodiment of the present invention.

FIGS. 1 to 3 show an embodiment of a stencil clamping device for a printing apparatus according to the present invention. In these figures, reference numeral 1 denotes a plate cylinder. The plate cylinder 1 is rotatably supported around its own central axis by a support structure (not shown), and is shown around its own central axis. At 1, it is driven to rotate counterclockwise.

A head member 7 having a clamp-side stage surface portion 3 and an unclamping-side stage surface portion 5 is fixedly mounted on a part of the outer peripheral portion of the plate cylinder 1, and a pivot shaft 11 is attached to the head member 7 by a bracket 9. It is mounted rotatably. The pivot 11 extends along the generatrix (axis) direction of the plate cylinder 1, and a clamp plate 13 made of a strip-shaped thin plate is fixedly mounted on the pivot 11.

The clamp plate 13 is rotationally displaced together with the pivot 11 so that the clamp plate 13 is in contact with the clamp-side stage surface portion 3 with the base paper interposed therebetween and the clamp position is separated from the clamp-side stage surface portion 3 and joined to the unclamping stage surface portion 5 ( (Unclamping position).

A small-diameter clamp driving gear 15 is fixedly mounted on one end of the pivot 11.

Location pins 17 are provided on the end surface of the plate cylinder 1.
The location of the location pin 17 is set on a straight line connecting the center of the pivot 11 and the center of the plate cylinder 1 as shown in FIG.

A motor 21 is fixedly mounted on a main body side of the printing apparatus by a bracket 19. A sector gear 25 is fixedly mounted on the rotation output shaft 23 of the motor 21. The sector gear 25 is rotated by the rotation output shaft 23 and the plate cylinder 1
Are selectively engaged with the clamp drive gear 15 in a state where the plate is positioned at the plate discharging / rotating position as shown in the figure. The tooth region angle θ of the sector gear 25 is set to an angle that rotates the clamp plate 13 between the clamp position and the release position per one rotation of the rotation output shaft 23. By rotating the rotation output shaft 23 clockwise in FIG. 2 while the plate cylinder 1 is fixed in the rotation direction, the clamp plate 13 rotates from the clamp position to the release position. On the other hand, the rotation of the rotation output shaft 23 in the counterclockwise direction in FIG. 2 causes the clamp plate 13 to rotate from the release position to the clamp position.

A locking plate 31 is attached to a fixed side plate 27 on the main body side of the printing apparatus by a guide roller 29 so as to be vertically movable. The locking plate 31 has a bifurcated portion 33 for selectively catching engagement with the location pin 17, and the bifurcated portion 33 is provided when the plate cylinder 1 is located at the rotation of the plate receiving and discharging plate as shown. 33 is between a lowered position in which the rotation of the plate cylinder 1 is prevented by engagement with the location pin 17 and a raised position in which the forked portion 33 is separated from engagement with the location pin 17 and freely rotates the plate cylinder 1. It is guided by the guide roller 29 and reciprocates up and down.

A sector cam 35 is fixedly mounted on the rotation output shaft 23 of the motor 21 in parallel with the sector gear 25. A cam engaging surface portion 37 is provided on an upper end portion of the locking plate 31. The cam engaging surface portion 37 is provided with a fan-shaped cam 35 by biasing the locking plate 31 upward by a spring 39 in FIG. Is in contact with

The sector cam 35 is attached to the rotation output shaft 23 with a predetermined rotational phase relationship with respect to the sector gear 25, and the rotation of the rotation output shaft 23 causes the locking plate 31 to resist the spring force of the spring 39. Prior to the engagement of the sector gear 25 with the clamp drive gear 15,
The cam shape is set such that the locking plate 31 is returned to the raised position by the spring force of the spring 39 after the sector gear 25 is separated from the engagement with the clamp drive gear 15 after the sector gear 25 is separated from the engagement with the clamp drive gear 15.

FIG. 4 shows the relationship between the vertical movement of the locking plate 31 and the period of engagement between the sector gear 25 and the clamp driving gear 15. In FIG. 4, a period A is a period in which the locking plate 31 is located at the lowered position and the rotation of the plate cylinder 1 is blocked, and a period B is a period in which the sector gear 25 and the clamp driving gear 15 mesh with each other. Is shown.

During a normal printing operation, the sector gear 25 and the locking plate 31 are at the initial positions as shown in FIG. 1 and do not prevent the rotation of the plate cylinder 1. At the time of exchanging the base paper, the plate cylinder 1 is stopped at the rotation position for plate discharge / discharge as shown in the figure, and the clamp plate 13 is in the clamp position as shown in FIG. From this state, the rotation output shaft 23 is rotated clockwise in FIG. 1 by the motor 21 so that the sector gear 25 and the sector cam 35 are rotated.
Both rotate clockwise.

With this rotation, first, the sector cam 35 pushes down the locking plate 31 against the spring force of the spring 39, and the locking plate 31
Is located at the lowered position. Thereby, the forked part 33
Engages with and captures the location pin 17 of the plate cylinder 1 at the rotation of the plate cylinder, and captures the same.
Is non-rotatably fixed to the plate discharge rotation position.

Further, the rotation output shaft 23 is
As a result, the locking plate 31 is kept at the lowered position by the fan-shaped cam 35, that is, the plate cylinder 1 cannot rotate to the loading / unloading rotation position by being rotated clockwise in FIG. In the fixed state, the sector gear 25 meshes with the clamp drive gear 15, and the sector drive gear 25 rotates the clamp drive gear 15 counterclockwise.
As a result, the clamp plate 13 is pivotally displaced from the clamp position to the release position together with the pivot 11, and the clamp plate 13 is joined to the unclamping stage surface portion 5 to release the used base paper from being clamped.

When the rotation output shaft 23 rotates until the clamp plate 13 is at the release position, the sector gear 25 is separated from the engagement with the clamp drive gear 15 and the clamp drive gear 15
Is stopped.

When the rotation output shaft 23 makes one rotation, it returns to the original state, and the printing cylinder 1 can be freely rotated. Thereafter, the printing cylinder 1 is rotated once, so that the outer circumference of the printing cylinder 1 is rotated. Plate discharging is performed to remove used base paper wound around the surface from the plate cylinder 1.

After completion of plate discharging, the rotation output shaft 23 is
As a result, the sector gear 25 and the sector cam 35 rotate together in the counterclockwise direction by being rotated in the counterclockwise direction in FIG. 1, and the locking plate 31 is first lowered by the sector cam 35 due to this rotation. The plate cylinder 1 is moved to the position, and the plate cylinder 1 is non-rotatably fixed again to the plate discharging and rotating position.

In this state, the leading end of a new base paper is set on the clamp-side stage surface portion 5, and thereafter, the rotation output shaft 23 is further rotated clockwise in FIG. In a state where the cylinder 1 is continuously fixed to the plate discharging rotation position so as not to rotate, the sector gear 2
5 meshes with the clamp drive gear 15, and the sector drive gear 25 drives the clamp drive gear 15 to rotate clockwise. As a result, the clamp plate 13 is pivotally displaced from the release position to the clamp position together with the pivot 15, and the leading end of the new stencil sheet is interposed between the clamp-side stage surface portion 5 and the clamp plate 13 and locked on the plate cylinder 1.

Then, after the rotation output shaft 23 makes one rotation and returns to the original state, the plate cylinder 1 is rotated once, so that a new base paper is wound around the outer peripheral surface of the plate cylinder 1 and mounted.

In the above embodiment, the sector gear 25 and the sector cam 35 are both provided directly on the rotary output shaft 23 of the motor 21. However, the sector gear 25 and the sector cam 35 are
As long as they are in the same drive shaft system rotated and driven by a single motor 21, they need not necessarily be provided on the same shaft.
For example, another gear may be interposed between the sector gear 25 and the rotation output shaft 23.

[0028]

As can be understood from the above description, according to the stencil clamping apparatus of the printing apparatus according to the present invention, the drive shaft system is driven to rotate by the rotary drive actuator, so that the sector gear and the cam rotate together. Before the sector gear meshes with the clamp drive gear, the locking member catches and engages with the location pin to prevent the plate cylinder from rotating, that is, the plate cylinder is fixed, and from this state, the rotary drive actuator continues to rotate. When the drive shaft system is driven to rotate, the sector gear meshes with the clamp drive gear, and the gear mesh drives the pivot to rotate the clamp member between the clamp position and the release position. Clamping and unclamping without the need for equipment, i.e. without multiple actuators Operation is reliably performed.

[Brief description of the drawings]

FIG. 1 is a rear view showing an embodiment of a base paper clamping device of a printing apparatus according to the present invention.

FIG. 2 is a front view showing an embodiment of a base paper clamping device of the printing apparatus according to the present invention.

FIG. 3 is an enlarged side view showing an embodiment of a base paper clamping device of the printing apparatus according to the present invention, with respect to main parts thereof.

FIG. 4 is a timing chart showing the relationship between the up and down movement period of the locking plate 31 and the engagement period between the sector gear 25 and the clamp drive gear 15 in the base paper clamp device of the printing apparatus according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Plate cylinder 3 Clamp stage surface part 5 Unclamp side stage surface part 11 Axis 13 Clamp plate 15 Clamp drive gear 17 Location pin 21 Motor 25 Sector gear 31 Lock plate 33 Bifurcated part 35 Sector cam 37 Cam engagement surface part

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) B41L 13/10 B41L 13/14 B41F 27/12

Claims (1)

(57) [Claims] 1. A stencil clamping device for a printing apparatus for clamping a stencil sheet on an outer peripheral surface of a rotationally driven plate cylinder, wherein the stencil plate is rotatably mounted on the plate cylinder by a pivot and is located between the outer peripheral surface of the plate cylinder. A clamp member movable between a clamp position for sandwiching and locking the base paper and a release position for releasing the locking of the base paper; a clamp drive gear mounted on the pivot; and a location pin mounted on the plate cylinder. A sector gear that is rotatably provided on the main body side of the printing apparatus and selectively meshes with the clamp drive gear; and is movably provided on the main body side of the printing apparatus and selectively captures and engages with the location pin. A locking member for locking the plate cylinder at a predetermined rotational position, and mounted on the same drive shaft system as the sector gear with a predetermined phase relationship with the sector gear, and the rotation of the drive shaft system causes the rotation. A cam that drives the locking member so that the locking member engages with the location pin before the sector gear meshes with the clamp drive gear; a rotary drive actuator that rotates the drive shaft system; A base paper clamping device for a printing apparatus, comprising: