JPH0663334U - Thermal head support device for line printer - Google Patents

Abstract

(57) [Abstract] [Purpose] To reduce the cost by reducing the number of parts of the thermal head support device in a line printer. [Structure] The left end of the leaf spring 15 is fixed to the thermal head 16 with a fixing screw 25. The U groove 23 of the bearing portion 22 provided in the middle portion of the leaf spring 15 is engaged with the head support shaft 14 provided in the body frame. The engaging portion 24 at the right end of the leaf spring 15 is engaged with the engaging groove 26 provided in the main body frame 11. As a result, the thermal head 16 is pressed by the plate spring 15 toward the platen 13 side. The reaction force acting on the leaf spring 15 is caused by the platen 13, the head support shaft 14 and the engaging groove 26, which are in a fixed position of the body frame.
The leaf spring 15 is held by receiving at three points. Therefore, the leaf spring 15 also functions as a head holding plate that elastically holds the thermal head 16 so as to absorb the parallel error between the platen 13 and the head support shaft 14. Therefore, it is not necessary to separately provide the head holding plate.

Description

[Detailed description of the device]

[Purpose of Invention]

[0002]

[Industrial applications]

 The present invention relates to a thermal head supporting device in a line printer.

[0003]

[Prior art]

 As shown in FIG. 4, in the conventional small-sized line printer, a platen 2 is rotatably supported on a main body frame 1, and a head support plate 4 is provided around a head support shaft 3 provided on the main body frame 1 as a center. Is swingably supported, a thermal head 5 is integrally provided on the lower surface of the head holding plate 4, and a spring 6 provided between the upper plate portion 1a of the body frame 1 and the head holding plate 4 A thermal head supporting device for pressing the thermal head (thermal line head) 5 toward the platen 2 is provided.

[0004]

[Problems to be solved by the device]

 As described above, the conventional thermal head support device requires three points, that is, the head support shaft 3, the head holding plate 4, and the spring 6, as the minimum necessary components, but in order to reduce the cost, this component is further required. It is necessary to reduce the score.

The present invention has been made in view of the above circumstances, and an object of the present invention is to reduce the number of components of the thermal head supporting device and reduce cost by replacing the head holding plate and the spring with a leaf spring. To do.

[Constitution of Device]

[0007]

[Means for Solving the Problems]

 The present invention movably mounts a thermal head 16 on a platen 13 pivotally supported on a main body frame 11 with a head support shaft 14 provided on the main body frame 11 as a fulcrum. In the line printer that presses against, the leaf spring 15 is used as the spring, one end of the leaf spring 15 is fixed to the thermal head 16, the middle portion of the leaf spring 15 is engaged with the head support shaft 14, and the leaf spring 15 Is a thermal head supporting device in a line printer in which the other end of is engaged with the main body frame 11.

[0008]

[Action]

 The leaf spring 15 of the present invention functions as a pressing spring that presses the thermal head 16 against the platen 13, and elastically holds the thermal head 16 so as to absorb the parallel error between the platen 13 and the head support shaft 14. It has a function as a head holding plate.

[0009]

【Example】

 Hereinafter, the present invention will be described in detail with reference to the embodiments shown in FIGS.

As shown in FIGS. 1 and 2, a platen 13 is rotatably supported on a body frame 11 by a platen shaft 12. Further, a head support shaft 14 is provided so as to span the main body frame 11, and a thermal head (thermal line head) 16 opposed to the platen 13 by a pair of leaf springs 15 is movably provided with the head support shaft 14 as a fulcrum. .

As shown in FIG. 3, the leaf spring 15 has a fixing screw insertion hole 21 at one end, and a pair of head support shaft engaging bearing portions 22 in the middle portion and a notch from the upper end of the bearing portion 22. The formed U groove 23 is provided, and the engaging portion 24 that engages with the main body frame 11 is provided at the other end.

Then, as shown in FIG. 1, one end of the leaf spring 15 is fixed to the thermal head 16 by the fixing screw 25 inserted into the insertion hole 21, and is attached to the middle portion of the leaf spring 15. The U groove 23 of the bearing portion 22 provided is engaged with the head support shaft 14, and the engagement portion 24 at the other end of the leaf spring 15 is engaged with the engagement groove 26 provided in the main body frame 11. .

As a result, the thermal head 16 is pressed against the platen 13 by the plate spring 15, and at the same time, the reaction force acting on the plate spring 15 is applied to the platen 13, the head support shaft 14 and the engaging groove in the fixed position. The leaf spring 15 is held by receiving at three points of 26.

In this way, the leaf spring 15 functions as a pressing spring that presses the thermal head 16 against the platen 13, and the thermal head 16 is installed so that the parallel error between the head support shaft 14 and the platen 13 can be absorbed. It has a function as a head holding plate for elastically holding. Therefore, the pressing force of the thermal head 16 against the platen 13 can be made uniform over the entire length of the platen 13.

Although a pair of leaf springs 15 are used in the above embodiment, one leaf spring 15 may be provided at the center of the thermal head 16.

[0016]

[Effect of device]

 According to the present invention, one end of the leaf spring is fixed to the thermal head, the middle portion of the leaf spring is engaged with the head support shaft provided on the body frame, and the other end of the leaf spring is engaged with the body frame. The plate spring not only functions as a thermal head pressing spring, but also as a head holding plate that can elastically hold the thermal head so as to absorb the parallel error between the head support shaft and the platen. Two types of parts, a holding plate and a spring, can be reduced to a leaf spring only, and the cost can be reduced by reducing the number of parts.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a thermal head support device in a line printer showing an embodiment of the present invention.

FIG. 2 is a front view of the same thermal head support device.

FIG. 3 is a perspective view showing a leaf spring used in the same thermal head supporting device.

FIG. 4 is a sectional view showing a conventional thermal head support device.

[Explanation of symbols]

 11 Body frame 13 Platen 14 Head support shaft 15 Leaf spring 16 Thermal head

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Akio Mizumura 1-1943 Higashi Oizumi 1-43, Higashi Oizumi, Nerima-ku, Tokyo Inside Tamura Corporation

Claims (1)

[Scope of utility model registration request] 1. A line printer in which a thermal head is movably provided on a platen pivotally supported by a main body frame with a head support shaft provided on the main body frame as a fulcrum, and the thermal head is pressed toward the platen by a spring. , A leaf spring is used as a spring, one end of the leaf spring is fixed to the thermal head, the middle portion of the leaf spring is engaged with the head support shaft, and the other end of the leaf spring is engaged with the main body frame. Thermal head support device for line printers.