Letter Punch

Abstract

A small-sized, light-weight and handy letter punch which comprises a base and an upper plate which are disposed in parallel to each other leaving a horizontal gap to receive documents to be punched therein and are connected at the side edges and end edges thereof forming a side wall and an end wall, respectively, and said upper plate being provided with a spring-actuated punch rod and said base being provided with a base plate having a punch hole to cooperate with said punch rod. The positioning of documents in punching is facilitated by fitting said documents to the insides of said side wall and end wall.

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to an improved letter punch. More particularly, the invention relates to an improved letter punch or letter perforator to make holes in sheets of paper, documents, slips or the like so as to file them. Still more, the present invention relates to a small-sized, light-weight and handy letter punch which is able to make a hole or holes in each sheet material as desired.

2. Description of the Prior Art

There are heretofore several letter punches which having one punch rod for making one hole or two punch rods for making two holes in each punching operation. In general, the two-hole punch is able to make separate two holes at a certain distance by a single operation, however, the size of the two-hole punch is somewhat larte and inconvenient to carry. While, the one-hole letter punch is a simplified type of said two-hole punch, so that when two holes are to be made by the one-hole punch which having only a depth guide, the distance between the punched holes is liable to vary which causes inconvenience in filing.

BRIEF SUMMARY OF THE INVENTION

In view of the above facts, the principal object of the present invention is to propose a novel and improved letter punch which having no defects as pointed out in the above.

Another object of the present invention is to propose said letter punch which having only one punch rod but being able to make two holes at a predetermined distance as well as one hole in like manner as the conventional one-hole punch.

A further object of the present invention is to propose the letter punch which is simple in structure, light in weight, easy to handle and reliable in perforation.

Still further, the object of the present invention is to propose the letter punch which can be easily produced at very low cost and in large quantities.

In accordance with the preferred embodiment of the invention, the letter punch of the present invention comprises a base and an upper plate which are disposed in parallel to each other leaving a horizontal gap to receive documents to be punched therein and are connected at the side edges and end edges thereof forming a side wall and an end wall, respectively. Further, said upper plate being provided with a spring-actuated punch rod and said base being provided with a base plate having a punch hole to cooperate with said punch rod. In the punching of the documents, the positioning can be carried out by fitting the edges of the documents to the insides of said side wall and end wall, because the distance between the center of said punch hole of said base plate and the inside of said end wall is equal to one half of the distance between the holes to be punched, and the distance between the center of said punch hole and the inside of said side wall is equal to the distance between the edge of binding side of documents to be punched and the hole to be formed.

Further, according to the present invention, the letter punch is provided with a waste box under the punch hole of said base plate to receive the waste paper of punching. Said punch rod to form the punched holes on the document is attached to said upper plate by forming a vertical cylinder on the upper surface of said upper plate and slidably inserting said punch rod into said cylinder. The upper end of said punch rod is provided with a punching knob and a coil spring is attached between this knob and said cylinder to impart the punch rod upward force. In punching, the punch rod is pushed down against the force of this coil spring.

Still further, the punching position can be correctly adjusted by providing positioning points to the upper surface of said upper plate of the letter punch.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other features of the present invention will be more fully understood by referring to the following detailed description presented solely for purpose of illustration and to the accompanying drawings in which:

FIG. 1 is a perspective view of an embodiment of the present invention;

FIG. 2 is a side elevation of the letter punch as shown in FIG. 1;

FIG. 3 is a vertical cross-sectional view of said letter punch;

FIG. 4 is a horizontal cross-sectional view taken along the line IV--IV in FIG. 3;

FIGS. 5 and 6 are plan views in partially cross-sections showing the positioning in punching; and

FIG. 7, (I) and (II) are plan views of sheets of paper which are perforated by the letter punch of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

Referring now to the accompanying drawings, especially to FIGS. 1 to 4, there is shown an embodiment of a letter punch of the present invention. This letter punch is rectangular in plan view, and comprises a base 1 and an upper plate 2 which are integrally connected on two sides to form a horizontal gap 3 for receiving documents to be punched. These base 1 and upper plate 2 may be formed by injection molding, compression molding or any other methods with using synthetic plastics. As shown in FIG. 4, said base 1 and upper plate 2 are connected by a side wall 4 and an end wall 5, which facilitate the positioning of documents in punching operation as explained in the following.

Further, said base 1 has a base plate 7 which is provided with a punch hole 6 in the middle portion thereof, and the lower side of said base plate 7 is provided with a waste box 9 having a lid 8. This lid 8 has a lip portion 10 which is inserted into a slot formed between an inside wall 9a and a bottom plate 12, thus the lid 8 can be swing-opened on said lip portion 10 as the fulcrum. Further, said lid 8 is provided with side lips 11 on the side edges and these lips 11 frictionally engage with both side walls of said waste box 9, thus the lid 8 can be supported on the bottom side of the waste box 9 when the lid 8 is closed. The remaining portion of the base 1 comprises a curved bottom portion 12 so that the thickness of the letter punch is reduced in this portion so as to facilitate the handling.

The above-mentioned upper plate 2 is provided with a vertical cylinder 13 which is concentric with the aforementioned punch hole 6 of said base plate 7, and a punch rod 14 is slidably inserted into this cylinder 13 directing its punch blade downward. On the upper end of said punch rod 14, a knob 15 is attached, and a coil spring 16 is provided between said knob 15 and inside stage of said cylinder 13. Thus the punch rod 14 can be kept at the withdrawn position away from the gap 3 by the spring action of said coil spring 16.

AS shown in FIGS. 4 and 5 in cross-sections, the base 1 and/or the upper plate 2 are provided with joint lips on the end edges and limited portions of side edges, and the base 1 and the upper plate 2 can be integrally assembled by inserting and bonding said joint lips with each other. By this connection of the joint lips, the aforementioned side wall 4 and end wall 5 for positioning the documents can be formed.

As these side wall 4 and end wall 5 determine the positions and distance of the holes to be made, the arrangement between these walls 4, 5, punch holes 6 and punch rod 14 must be made exactly. That is, as shown in FIG. 4, the distance A between the center of punch hole 6 and the inner surface of said end wall 5 is equal to one half of the distance between the two holes to be made, and the distance B between the center of the punch hole 6 and the inner surface of said side wall 4 is equal to the distnace between the center of punched hole and the edge of document. Further, the distance between the free end of the side wall 4 and the center of the punch hole 6 is also made B as shown in FIG. 4.

When punching a document, for example a letter, by using the letter punch as disclosed in the above, the letter may be inserted into said horizontal gap 3 and then the knob 15 on the upper plate is only pushed down.

The example as shown in FIG. 5 is a case in which two holes are to be made on a letter in order to bind the letter to a fastener of a file. The letter 17 is firstly folded in two at the center or a desired position, the folded letter 17 is then inserted into the gap 3 of the letter punch so as to fit the folded side 18 to the end wall 5 and the binding side 19 to the side wall 4. Then, the knob 15 may be pushed down by a finger tip against the force of the coil spring 16, thereby the punch rod 14 is depressed to punch through the letter 17 and the cut paper is dropped into the waste box 9. When the force of finger tip to the knob 15 is removed, the punch rod 14 returns to the origianl position by the force of the coil spring 16 and the letter having punched holes is released. The letter 17 after the punching is shown in FIG. 7 (I), in which the punched holes 20 are made at the distance of 2A and a distance of B from the binding side 19.

The example as shown in FIG. 6 is a case in which one hole is to be made on a letter. In this case, the binding side 19a of the letter 17a is inserted to the horizontal gap 3 as far as the side 19a reaches the end portion of said side wall, and the knob 15 is then pushed down to make a hole by the punch rod 14. When punched in this manner, the hole 20a at any position in a distance B apart from the edge of binding side 19a of the letter 17a as shown in FIG. 7 (II) can be made because the both sides of the punch rod 14 are free and the letter 17a can be moved up and down in FIG. 6. The positioning of the document in punching may be made correctly by a positioning point 21 indicating the position of punch rod 14 and a positioning point 22 indicating the edge of the binding side 19a, both points 21 and 22 being formed on the surface of upper plate 2. Further, according to the above method, any number of holes with any intervals may be formed in the letter.

As disclosed in the above, any necessary punch holes 20, 20a may be formed in the documents 17, 17a by using the punch of the present invention, in addition, though the punch rod 14 is only one, any number of holes can be made. For example, when three holes are to be made along the binding side, two holes are firstly made according to the method as shown in FIG. 5 and the other one hole may be made by the method as shown in FIG. 6 on the fold line 18 by opening the punched letter.

In the modifications of the present invention, the upper palte 2 can be connected to the base 1 only by the end wall 5, and the configuration in plan view of the upper plate 2 is not always the same as that of base 1. Further, the punch rod 14 may be moved integrally with the upper plate 2 by using elastic material. Still further, the end wall 5 and the side wall 4 can be formed by latticework or bar construction and the end portion of the side wall 4 may be provided with a separate guide wall.

It will be understood that the letter punch of the present invention can be made as small as being held in a palm of a lady, and that the letter punch of the invention is light-weight, small sized and simple in structure, and convenient and handy in use. It should be emphasized, however, that the specific embodiments described and shown herein are intended as merely illustrative and in no way restrictive of the invention.

Claims

What is claimed is:

1. A letter punch which comprises a base and an upper plate which are disposed in parallel to each other leaving a horizontal gap to receive documents to be punched therein and are connected at the side edges and end edges thereof forming a side wall and an end wall, respectively, and said upper plate being provided with a spring-actuated punch rod and said base being provided with a base plate having a punch hole to cooperate with said punch rod.

2. A letter punch as claimed in claim 1, in which the distance between the center of said punch hole of said base plate and the inside of said end wall is equal to one half of the distance between the holes to be punched, and the distance between the center of said punch hole of said base plate and the inside of said side wall is equal to the distance between the edge of binding side of document to be punched and the holes to be formed.

3. A letter punch as claimed in claim 1, in which a waste box is formed under said base plate to receive the waste paper of punching.

4. A letter punch as claimed in claim 1, in which said upper plate is integrally provided with a vertical cylinder which being concentric with said punch hole of said base plate, and said punch rod is installed within said cylinder and forced by a coil spring by way of a knob attached at the upper end of said punch rod.

5. A letter punch as claimed in claim 1, in which said upper plate is provided with positioning points, each of which indicating the center of punch rod and the end portion of said side wall.

6. A letter punch as claimed in claim 1, in which said base and upper plate are connected by bonding the joint lips provided along the edges of said members, and thereby forming rectangular side wall and end wall to faciliate the positioning of documents to be punched.

7. A letter punch as claimed in claim 1, in which the size of said punch is such that the punch can be held within a palm.