JPH0712727B2 - Printhead position adjustment device - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a print head position adjusting device used in printers, typewriters, and the like.

2. Description of the Related Art In recent years, printing devices such as printers and typewriters have
In order to improve the efficiency of printing work, there has been an increasing number of methods of stacking several sheets of paper at once and making original copies at the same time. Therefore, it is necessary to change the gap between the platen of the print head and the thickness of the paper.

There are conventional position adjusting devices for print heads, in which the auxiliary shaft is eccentric and the rotation thereof changes the height to change the clearance between the print head and the platen, or the platen moves back and forth.

A conventional print head position adjusting device will be described below.

FIG. 6 is a side view of a conventional print head position adjusting device. In the figure, 1 is a platen, 2 is a main shaft, 3 is a main shaft sleeve, and the main shaft 2 penetrates the main shaft sleeve 3. Four
Is the rear shaft. 5 is an eccentric pin and the rear shaft 4
Are provided at both ends of. 6 is a solenoid, 7 is a mount,
A ribbon cassette 8 is mounted on the gantry 7. Reference numeral 9 is a print head incorporating a print hammer 9a, and 10 is a carriage base.

The operation of the conventional print head position adjusting device configured as described above will be described.

Incidentally, FIG. 7 shows a state in which the gap between the print head and the platen is made wider than the state shown in FIG.

When widening the gap between the platen 1 and the tip of the printing hammer 9a, the rear shaft 4 is rotated around the eccentric pin 5 in the direction of the arrow θ so that the carriage base 10 is moved to the main shaft 2.
By rotating in the direction of θ ′ around the center, the gap between the platen 1 and the printing hammer 9a becomes large. On the contrary, when the gap is reduced, the operation reverse to the above operation may be performed.

Problems to be Solved by the Invention However, the conventional position adjusting device for a print head as described above has a problem that manufacturing process such as polishing of the eccentric pin of the rear shaft is very difficult and cost is increased.

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above-mentioned drawbacks and to provide an inexpensive print head position adjusting device which is easy to manufacture and process.

Means for Solving the Problems In order to solve the above problems, a print head position adjusting device of the present invention supports a platen having a printing surface on a chassis, and a main member supported on the chassis in parallel with the printing surface. A shaft and a carriage that is mounted parallel to the main shaft on a rear plate supported by the chassis as a guide and is slidable by being guided by the main shaft and sliding on a rear plate provided at a portion facing the rear plate of the carriage. An inclined plate inclined to the surface, a plate receiver interposed between the inclined plate and the rear plate and moving relative to the inclined plate, and interlocked with the plate receiver at a position facing the plate receiver via the inclined plate. And a projecting portion formed integrally with the plate receiver, and a bullet that is sandwiched between the projecting portion and the slanting plate to urge the slanting plate toward the plate receiving part. Sex member,
It is provided with a plurality of concavo-convex portions formed at positions where the elastic member on the protrusion side of the inclined plate is in pressure contact.

By moving the work plate receiver relative to the carriage, the gap between the print head mounted on the carriage and the printing surface of the platen can be adjusted.

EXAMPLES Examples of the present invention will be described below with reference to the accompanying drawings. In FIG. 1, 13 is a rear plate, both ends of which are fixed to a chassis (not shown). Reference numeral 11 denotes a plate receiver, and the sliding surface with the carriage base has an inclined surface 11b that is inclined with respect to the sliding surface with the rear plate, and is also inclined to the carriage-side sliding surface that slides with this inclined surface 11b. A surface 12a is provided. Further, the plate receiver 11 has a lever 11a.
Are integrally formed. 12 is a carriage base, 14 is a platen, 15 is a print head, 16 is a ribbon cassette, and 17 is a main shaft. FIG. 3 shows a view of the structure shown in FIG. 1 from the left side of the drawing.

4 and 5 are views for showing the movement of the plate receiver 11.

The plate receiver 11 is biased upward by a spring 18, and the plate receiver 13 is positioned by a wavy protrusion provided on the carriage base side of the lower surface of the spring. FIG. 5 shows a state in which the rear plate receiver 13 is moved to the right from the state shown in FIG. Further, FIG. 2 shows a side view of the main part in that case.

In FIGS. 1 and 4, when the plate receiver 11 is moved in the arrow A direction, the carriage base 12 is lowered in the B direction. As a result, the carriage base 12 rotates about the main shaft 17 in the counterclockwise direction (arrow θ'direction) and the platen 14 moves.
And the gap between the print head 15 and the print head 15 widens. Further, in order to reduce the gap between the print head 15 and the platen 14, the operation reverse to the above operation may be performed.

As described above, according to the present embodiment, in a printing apparatus capable of printing with various thicknesses of paper, it is possible to simply use a plate without using a large-scale structure such as providing an eccentric mechanism on a rear shaft as in the conventional case. It is possible to easily change the distance between the print head and the platen print surface by moving the lever 11a provided on the receiver 11 to the left and right.

Effect of the Invention The present invention adjusts the position of the print head on one side of the inclined plate,
Since the adjusted position can be held on the other side and the two functions are realized on both sides of the inclined plate, the device can be downsized, and the plate receiver and the protruding portion are sandwiched so as to sandwich the inclined plate. Since the elastic member is integrally formed and the elastic member is sandwiched between the protrusion and the inclined plate, the position adjustment and the holding of the adjusted position are integrally formed on the inclined plate, the elastic member, the plate receiver and the plate receiver. It is possible to realize an excellent print head position adjusting device that can be configured with three parts including a protrusion and can reduce the number of parts.

[Brief description of drawings]

FIG. 1 is a side view of a position adjusting device for a print head showing one embodiment of the present invention, FIG. 2 is a side view of a main portion after movement, and FIG.
FIG. 4 is a rear view of a main part, FIG. 4 is a rear cross-sectional view before movement, FIG. 5 is a rear cross-sectional view after movement, FIG. 6 is a side view of a conventional print head position adjusting device, and FIG. It is a side view after position adjustment of a moving device. 11 …… Plate receiver, 11a …… Lever 12 …… Carriage base, 12a …… Sliding surface 13 …… Rear plate, 14 …… Platen 15 …… Printing hammer, 16 …… Ribbon cassette 17 …… Main shaft

Claims (1)

[Claims] 1. A platen having a print surface is supported by a chassis, and a main shaft supported by the chassis parallel to the print surface and a rear plate supported by the chassis parallel to the main shaft are mounted as guides. A carriage that is slidable while being guided by the main shaft; an inclined plate that is provided in a portion of the carriage that faces the rear plate and that is inclined with respect to a sliding surface of the rear plate; A plate receiver that is interposed between the rear plate and moves relative to the inclined plate, and is integrally formed with the plate receiver at a position facing the plate receiver through the inclined plate so as to interlock with the plate receiver. A protrusion, and an elastic portion sandwiched between the protrusion and the inclined plate and biasing the inclined plate toward the plate receiver. When the position adjustment device of the print head, characterized in that a plurality of uneven portions formed in a position wherein the elastic member and pressed against the protrusion side of the inclined plate.