JPS6127753Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a paper press plate for wrapping and fixing base paper or manuscript paper around a drum or platen of a copying plate making machine or the like.

2. Description of the Related Art It is well known that a paper press plate, which can be attached to and detached from a drum or platen, is used as a means for winding paper around a drum or platen.

This paper holding plate presses and fixes the overlapping portions of both edges of the paper to the drum, but it not only improves operability when loading and unloading the paper, but also prevents the paper from shifting or sagging while the machine is operating. It is necessary to be able to firmly press and hold the product without causing any damage.

In particular, when increasing the plate-making speed in a printing plate-making machine, it is essential that the drum rotates at a high speed, and as the drum rotates at a high speed, the centrifugal force or wind pressure applied to the paper on its surrounding surface increases at an accelerating rate. For this reason, with the conventional paper presser plate, there is a risk that the paper will separate from the drum.

The present invention provides a paper press plate that can maintain a sufficiently strong pressing force even at such high speed rotation.

Before explaining the configuration of the present invention, a conventional presser plate will be explained.

In FIG. 1, 1 is a drum, 2 is a recess formed in the axial direction on the circumferential surface of the drum, 3 and 4 are stepped surfaces on both sides of the recessed portion, and 5 is a paper edge insertion groove provided between the two steps. It is. Reference numeral 6 denotes a paper press plate, which is constructed by a single elastic metal piece 7 having both ends curved outward, or a rubber plate 8 etc. attached to the back surface thereof. Reference numeral 10 denotes a sheet of paper wound around a drum, both edges 11 and 12 of which are overlapped in the recess 2 and pressed and fixed by a presser plate 6 from above.

In the above-mentioned conventional product, it is possible to increase the pressing force and the frictional resistance with the paper surface to a certain extent by thickening the leaf spring 7 and further thickening the rubber layer 8. The depth will have to be increased. Therefore, it is not practical to increase the depth of the recess, and even if this method is done, it is not possible to strengthen the paper pressing and fixing force to the extent that it can withstand high-speed rotation. This is limited to low-speed machines with a drum rotation speed of about 300 to 600 v.pm.

The present inventor created a plastic molded cushion material in which a central ridge 20 is bulged from the same leaf spring so that the paper surface can be held in pressure contact with each end of the recessed steps 3 and 4 facing each other with the paper edge insertion groove 5 in between. 9 was attached and an experiment was conducted, and it was confirmed that a stronger pressing force than before was obtained.

The pressing force on the holding plate is generated by a leaf spring, and it is obvious that the pressing force of the leaf spring increases as the thickness of the leaf spring increases, provided that the material of the leaf spring is the same.

However, as described above, the thickness of the presser plate is limited by the thickness of the drum recess, so if the leaf spring is made thicker, the molded elastic cushion material 9 must be made thinner.

However, it is generally difficult to form a molded product with a small thickness, and the cost also increases.

The pressing plate of the present invention shown in FIG. 3 can increase the pressing force by making the plate spring relatively thick, and at the same time, exhibits a strong fixing effect even if the cushion material is thin.

In other words, it provides a particularly effective structure when the cushion material must be made thin.

The cushion material 9 in the present invention is a thin rubber plate or sponge plate 31, which is bonded to the back surface of the leaf spring 7 through a rod-shaped body 32 of hard rubber or other material at the center in order to provide the ridge portion 20 in a protruding manner. Due to the insertion of the rod-shaped body 32, the cushion material has a ridge 20 and a slope 21.
are formed at the same time, and a small gap is created between the sloped portion and the rod-shaped body, so that the cushioning effect is good. Furthermore, unlike molded products, a mold is not required, so there is an advantage that the cost can be significantly reduced, the thickness of the cushion material can be freely selected, and the thickness can be made thinner than in the case of molded products.

The above-mentioned original pressing plate has a ridge portion 20 that bulges in the center.
and elastic slopes 21 connected to the left and right sides of the drum, the paper in the recessed portion of the drum is pressed by the slopes 21 against the ends 3', 4' of the surface facing the stepped portion, and its center portion is pressed against the ridge 20. Therefore, due to the tension caused by being pushed into the groove 5, the pressing contact force at the end is further strengthened.

In this product as well, the flat part 22 has a pressing action as in the conventional product, and together with the pressing force, it can exert a strong fixing action, and even at a drum rotation speed of 800 to 1000 rpm. Can be held stably.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a main part of a conventional product, FIG. 2 is an enlarged sectional view of a main part of an improved product of the conventional product, and FIG. 3 is a perspective half-cut sectional view of a product according to the present invention. 3', 4' are the ends, 5 is the groove, 20 is the bulging ridge, 2
1 is a slope.

Claims (1)

[Scope of utility model registration request] In a removable paper press plate that presses the edge of paper against a grooved recess formed in the axial direction on the circumferential surface of a drum, etc., a rod-shaped body is installed in the center of the back side of a metal plate having a spring action. A paper press plate in which a rubber plate is adhered to cover the rod-shaped body, so that a peak part is bulged in the center, and slopes contacting opposite ends of the concave step part are formed on both sides of the peak part.