JPH085578B2 - Pin tractor - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pin tractor for feeding a paper used in various printers, typewriters and the like used as output devices for electronic computers, particularly personal computers.

(Prior Art) Generally, in various printers, typewriters, etc. used as output devices of electronic computers, in order to feed the paper used for them, the pins of an endless belt with pins are fed to both side edges of the paper. A pin tractor is used that feeds a sheet by engaging a hole and rotating a belt with a pin. In such a pin tractor,
Conventionally, as described in, for example, U.S. Pat. No. 4214691, a frame is movably supported by a guide shaft and a drive shaft arranged in parallel, and the position can be adjusted according to the width of a sheet to be fed. The lock means is provided so that it can be fixed to the guide shaft at a desired position.

(Problems to be Solved by the Invention) However, the locking means includes a tubular fixing member that is provided on the frame and is externally fitted to the guide shaft, and a lever that is rotatably externally fitted to the fixing member. Since the frame is usually formed of two members so that the toothed pulley can be supported from both sides, the number of parts is large, the cost is high, and the assembly is troublesome.

The present invention has been made in view of the above points, and an object of the present invention is to provide an inexpensive pin tractor with a reduced number of parts by forming the frame with a single member and using a simple locking means. To do.

(Means for Solving the Problems) In order to achieve the above object, the present invention provides a frame movably supported by a guide shaft, a locking means for fixing the frame to the guide shaft, and one end of the frame. The drive toothed pulley and the driven pulley rotatably supported at the section, and the pins wound around the pulleys and engaged with the paper feed holes on the surface of the belt base, are the back surface of the belt base. And a belt with a pin, each of which is provided with a tooth portion that meshes with the driving toothed pulley, and the locking means has a modified inner diameter mounting hole provided in the frame, and a radius fitted into the mounting hole. And an operating member having a tubular portion that is deformable in the direction, and the driven pulley is rotatably supported by the tubular portion of the operating member.

(Example) Hereinafter, the Example of this invention is described based on drawing.

In the paper feeding apparatus shown in FIG. 1, reference numerals 1 and 1 denote pin tractors having a width of the paper S with respect to a drive shaft 2 having a rectangular cross section and a guide shaft 3 having a circular cross section, which are arranged substantially parallel to each other. It is installed at the appropriate distance.

As shown in FIGS. 2 to 4, each of the pin tractors 1 has a plurality of pins 4 engaging with the feed holes S ₁ provided on both side edges of the paper S on the surface of the belt base at regular intervals. It has a belt 6 with a pin, which is projected and has a tooth portion 5 provided on the back surface,
By rotating the belt 6 with pins, the paper S
Is sent at a substantially constant speed. Belt with pin 6
Tooth portion 5 meshes with a drive toothed pulley 7 that is inserted into the drive shaft 2 so as to be movable only in the axial direction, and engages with a driven flat pulley 8 so that the pinned belt 6 rotates. It is designed to be driven.

The frame 9 of the pin tractor 1 is made of synthetic resin, and as shown in FIGS. 5 and 6, a protrusion 11 is formed in the central portion of one side surface of a substantially rectangular substrate portion 10. A support portion 13 on which a pressing member 12 made of synthetic resin is rotatably supported is formed in a protruding manner on the upper portion of 11. Then, between the frame 9 and the pressing member 12, the pin 4 of the belt 6 with pins is
The sheet S engaged with is held.

In addition, mounting holes 14 and 15 are formed on both sides of the protrusion 11 of the base plate portion 10 so as to penetrate the base plate portion 10, and one of the mounting holes 14 is fitted to the drive shaft 2 so as to rotate integrally. A toothed pulley 7 is rotatably supported. The driving toothed pulley 7 includes, as shown in FIG. 7, a pulley body 16 having a tooth portion 16a,
It comprises a flange 17 provided on one side of the pulley body 16 and a projecting portion 18 provided on the other side of the pulley body 16 and having a circumferential groove 18a, and the circuit board portion 10 is provided in the circumferential groove 18a of the projecting portion 18.
A locking portion 19 formed on the opposite side of the above is fitted and is rotatably attached to the substrate portion 10. A positioning mark 40 for the pinned belt 6 is provided on the exposed surface of the flange 17 (see FIG. 2).

Further, a driven flat pulley 8 is rotatably mounted in the other mounting hole 15 via a lock member 20 for fixing the pin tractor 1 to the guide shaft 3. Driven flat pulley 8
Is attached to one end of the pulley body 21 as shown in FIG.
A protrusion 22 to be fitted into the connector 15 is provided, and a flange 23 is provided at the other end.

Further, the mounting hole 15 has a shape in which the inner diameter changes in the circumferential direction, and the first hole 15e is formed by facing flat portions 15a and 15b, and circular curved portions 15c and 15d that connect them, First
And a circular second hole 15f continuous in the axial direction of the hole 15e.

As shown in FIGS. 9 and 10, the lock member 20 includes a lever portion 25 at one end of a tubular portion 24 and a retaining collar portion 26 at the other end.
Are provided respectively, and the guide shaft 3 is passed through them.
A through hole 27 is provided for inserting the. The tubular portion 24 is provided with axial flat surfaces 24a, 24a back to back, and the tubular portion 24 and the collar portion 26 are linearly formed at a position deviated from the flat surfaces 24a, 24a by approximately 90 degrees in the circumferential direction. Slits 24c, 24c are formed respectively.

As a result, the lock member 20 is rotated so that the flat surfaces 24a, 24a of the lock member 20 are flat in the first hole 15e of the mounting hole 15.
When the circumferential curved surface of the tubular portion 24 is restricted by the flat portions 15a and 15b away from 15b, the tubular portion 24 is deformed so as to reduce the inner diameter of the through hole 27, and thereby the guide shaft 3 is fixed. The pin tractor 1 is immovably fixed to the guide shaft 3 because it is pressed against and tightened.

As shown in FIG. 11, the holding member 12 is provided with a long hole 28 at a position corresponding to the movement path of the pin 4 of the pinned belt 6, and the engaging hole 13a of the support portion 13 of the frame 9 is formed. Shafts 29 and 30 that engage with 13b are provided. The shaft portions 29 and 30 are respectively provided so as to project from arm portions 32 and 33 that project from the substrate portion 31 in the same direction. One arm portion 32 is longer than the other arm portion 33, and a tip portion 32a as a claw portion has a support portion 1
It is elastically fitted in the recess 13c of 3 to hold the pressing member 12 at a predetermined opening. In addition, the shaft portions 29 and 30 respectively project in opposite directions.

According to the above-mentioned structure, the belt 6 with a pin is wound around the frame 9 from one side to attach the driving toothed pulley 7 and the driven flat pulley 8 to each other, and the driven flat pulley 8 is locked. Since it can be assembled by applying the member 20, the assembly workability is extremely good. Moreover, at that time, since the belt 6 with pins can be attached while observing the positioning mark 40, it is easy to position the pins of the belt 6 with pins on the left and right with respect to the drive shaft 2.

(Effects of the Invention) Since the present invention is configured as described above, it is possible to reduce the number of parts and manufacture at low cost.

[Brief description of drawings]

The drawings show an embodiment of the present invention. FIG. 1 is a perspective view of a paper feeding device using a pin tractor, and FIGS. 2 to 4 are a front view, a plan view and a partial sectional side view of the pin tractor, respectively.
5 is a plan view of the frame, FIG. 6 is a front view of the frame, FIGS. 7 and 8 are front views of a driving toothed pulley and a driven flat pulley, and FIGS. 9 and 10 are respectively. FIG. 11 is a front view and a partial sectional side view of the lock member, and FIG. 11 is a plan view of the pressing member. 1 ... pin tractor, 2 ... driving shaft, 3 ... guide shaft, 6
...... Pin belt, 7 …… Drive toothed pulley, 8 …… Flat pulley for driven, 9 …… Frame, 15 …… Mounting hole, 20 ……
Lock member, 24 …… Cylindrical part.

Claims (1)

[Claims] 1. A pin tractor for feeding a sheet having feed holes on both side edges, a frame movably supported by a guide shaft, a lock means for fixing the frame to the guide shaft, and one end portion of the frame. At the back surface of the belt base, there are a driving toothed pulley and a driven pulley rotatably supported in A belt with a pin, each of which has a tooth portion that meshes with the driving toothed pulley;
The locking means includes a mounting hole having a modified inner diameter provided in the frame, and an operating member having a tubular portion that is fitted into the mounting hole and is deformable in the radial direction. A pin tractor, wherein the driven pulley is rotatably supported.