JPH0911582A - Small-sized printer - Google Patents

Abstract

PURPOSE: To provide a small-sized printer by fixing a circuit board to a base plate at the part approaching a connection pawl through the conductive rivet provided corresponding to the connection pawl to exclude the effect by static electricity to the utmost. CONSTITUTION: A control substrate 20 provided with a group of elements controlling the sequence control of a printer is integrally attached to a base plate 5 by a conductive rivet 25. The cut piece 33 of a suppressing plate 30 comes into contact with a part of a frame 6 by its elastic force so as to correct the shift of upper and lower cases 1, 10 to set a panel substrate 17 to earth potential and a vertical plate part 32 is pressed to the rear surface of a central rear wall 11 by the elastic force of the cut piece 33 to hold the flexible substrate 26 extending along the rear surface of the upper case 10 in cooperation with a horizontal part 31 so as to shield the same from the inside thereof. The flexible substrate 26 is suppressed from the entanglement with a movable part such as a carriage and held so as to suppress the effect by noise.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a small-sized printer whose main purpose is to prevent static electricity.

[0002]

2. Description of the Related Art In a small printer configured to invert a recording sheet fed from a hand at a printing unit and discharge it above a paper feeding unit, normally, a casing is provided in a lower case and an upper case so as to cope with jam processing and the like. The lower case supports the control board and the mechanical body via the base plate, while the upper case has an operation panel arranged on the upper surface.

Therefore, in this type of printer, conduction cannot be surely performed due to a gap between the circuit board on the upper case side and the mechanical body on the lower case side, or a part of the circuit board is vertically displaced. In the case of being located near the joint of the case, there is a problem that the element is damaged by being exposed to static electricity discharged at the joint.

[0004]

SUMMARY OF THE INVENTION The present invention has been made in view of such a problem.
It is to provide a new small printer that can eliminate the influence of static electricity as much as possible.

[0005]

That is, according to the present invention, as a small-sized printer for achieving such a problem, a circuit board in a portion close to the engaging portions of the case is made to correspond to these engaging portions. By fixing to the base plate via the provided conductive screw, at the same time, static electricity discharged from the engaging portion is released to the base plate via the screw.

[0006]

Embodiments of the present invention will be described below. The drawings all show one embodiment of the present invention.

In the drawings, reference numeral 1 is a lower case, and a base plate 5 provided on the lower case 1 is provided with a series of paper feed rollers, platen rollers, paper discharge rollers and a sheet discharge roller which constitute a sheet conveying path (not shown). A driving motor and a driving force transmission mechanism to be operated are arranged in a state of being supported by a frame (not shown), and a carriage is arranged in the vicinity of the platen roller via the frame 6 so as to be axially movable. A control board 20 provided with a group of elements for performing sequence control of the printer is integrally mounted on the base plate 5 with conductive screws 25.

As shown in FIG. 2, a part of the control board 20 of this type arranged in the small printer is located close to the one side wall 2 and the rear side wall 3 of the lower case 1, but in particular, . Are provided at the edge portion of the control board 20 close to the rear side wall 3 so as to face the engagement holes 4 provided in the rear side wall 3, and the control is performed by the screw 25a. While the substrate 20 is fixed on the base plate 5, static electricity discharged from the engaging claws 13 of the upper case 10 described later is released to the base plate.

A ground pattern 21 is provided on the rear surface of the control board 20 near the rear side wall 3 of the lower case 1 so as to be electrically connected to the screw 25a. Window holes 22 are formed in the edge portion so as to face openings such as the engagement holes 4 provided in the rear side wall 3, and the window holes 22 are exposed on the substrate 20. By the ground pattern 21
The static electricity discharged from the opening of the lower case 1 is released to the base plate 5.

On the other hand, the upper case indicated by reference numeral 10 in the drawing is
After that, the engaging claws 13 protruding from the back surface of the side wall 12 are engaged with the engaging holes 4 of the lower case 1, and are assembled on the lower case 1.

An operation panel 16 is provided on the upper surface of the upper case 10 on the front side of the top plate 14, and a panel board 17 electrically connected to the operation panel 16 is located behind the center of the upper case 10. Flexible boards 26 extend along the respective back surfaces from the wall 11 to the side walls 2 of the lower case 1 through the side walls thereof, and the other ends thereof are connected to the connectors 23 on the control board 20.

By the way, the restraining plate 30 shown in FIG. 4 presses and supports the flexible substrate 26 from the rear surface of the top plate 14 of the upper case to the rear surface of the central rear wall 11 while shielding the flexible substrate 26 and charging the panel substrate 17 with electric charges. Plays a role of dropping the above into the base plate 5 of the lower case 1 through the frame 6.

This restraining plate 30 is formed of a wide steel plate having elasticity, and the center thereof is L in the longitudinal direction.
Flexible circuit board 2 by bending in a letter shape
6 is formed as a horizontal plate portion 31 and a vertical plate portion 32 that press and support 6, and further, both sides of the vertical plate portion 32 are bent so as to project inward to form contact pieces 33, 33.

A part of the horizontal plate portion 31 of the holding plate 30 is
It is fixed to the back surface of the panel substrate 17 with screws 35 in a conductive state, and in this state, the contact piece 33 at the other end is brought into contact with a part of the frame 6 by its elastic force and holds the panel substrate 17 at the ground potential. There is. On the other hand, in this state, the horizontal plate portion 31 is pressed against the back surface of the top plate 14 of the upper case 10 by its elastic force, and the vertical plate portion 32 is pressed against the back surface of the central rear wall 11 by the reaction force of the contact piece 33. The flexible board 26 extending from the rear surface of the top plate 14 of the upper case to the rear surface of the central rear wall 11 is configured to be pressure-contacted and supported while being shielded by these plate portions 31 and 32.

In the embodiment constructed as described above, the engaging claws 13 of the upper case 10 are fitted into the engaging holes 4 of the lower case 1, and the upper case 10 is rotated while the upper case 10 is rotated about this point. 1, the contact pieces 33, 33 of the restraining plate 30 come into contact with a part of the frame 6 so as to fill the gap between the upper and lower cases 1, 10 by its elastic force, as shown in FIG. , The panel board 17 is set to the ground potential, and the vertical plate portion 32 is pressed against the back surface of the central rear wall 11 by the volatilization force of the contact piece 33. The flexible substrate 26 extending along the length is held so as to be shielded from the inside, and the flexible substrate 26 is held so as not to be entangled in a movable portion such as a carriage, and at the same time, to be prevented from being affected by noise.

On the other hand, under this assembled state, a part of the control board 20 is close to the rear side wall 3 of the lower case 1,
It becomes easy to be exposed to the static electricity discharged from the opening provided on this surface and the engaging claws 13 protruding on the inner surface of the upper case 10. However, as described above, the control board 20 has a portion facing the opening. The windows 22 are provided, and the ground pattern 21 provided on the back surface is used as the windows 22.
Since the panel substrate 20 is attached to the conductive base plate 5 by screws 25a provided at a portion facing the engaging claws 13, the panel substrate 20 is not exposed from the opening or the engaging claws 13. The discharged static electricity is directly flown to the base plate 5 via the ground pattern 21 and the screw 25a, and the generation of noise is suppressed in advance.

[0017]

As described above, according to the present invention, a conductive elastic plate is interposed between the panel substrate provided in the upper case and the mechanical body provided in the lower case, and the conductive elastic plate is extended inside the case. Since this flexible circuit board was pressed and supported by being covered with this elastic plate, the electrical continuity between the panel board and the machine body was ensured regardless of the deviation in the assembly of both cases, and The effect is eliminated, and the elastic force of this elastic material enables the flexible substrate to be effectively shielded and stably held.

Further, a portion of the circuit board near the engaging portions of both cases is fixed to the base plate by conductive screws provided so as to correspond to these engaging portions,
Further, the conductive film provided on the back surface of the circuit board so as to be connected to the screw is exposed on the surface by the window hole provided in the portion extending to the opening portion on the side surface of the case, so that the engaging claw is provided. The static electricity discharged from the openings and the openings can be released to the base plate through the conductive film exposed from the screws and the window holes, and the influence of static electricity on the element can be prevented in advance, and the generation of noise is effective. Can be eliminated.

[Brief description of the drawings]

FIG. 1 is a side view of a small printer showing an embodiment of the present invention.

FIG. 2 is a top view of the above printer.

FIG. 3 is a rear view showing a circuit board portion of the printer.

FIG. 4 is a perspective view showing a pressing plate.

[Explanation of symbols]

 1 Lower Case 3 Rear Side Wall 4 Engagement Hole 5 Base Plate 10 Upper Case 13 Engaging Claw 14 Top Plate 17 Panel Substrate 20 Control Substrate 25 Screw 26 Flexible Substrate 30 Suppression Plate 33 Contact Piece

Claims (3)

[Claims] 1. A small-sized printer configured to integrally combine upper and lower cases by engaging an engaging claw with an engaging hole, wherein a circuit board in a portion close to the engaging claw is
A small printer characterized by being fixed to a base plate via a conductive screw provided corresponding to the engaging claw. 2. A small printer, wherein upper and lower cases are integrally combined by engaging an engaging claw with an engaging hole, and a conductive film for connecting a conductive screw is provided on a back surface of a circuit board. A window hole for exposing the conductive film is formed on the upper surface of the circuit board in a portion close to the opening of the case side wall including the engagement hole. Small printer to do. 3. A small printer, wherein upper and lower cases are combined and integrated by engaging an engaging claw with an engaging hole, and a machine provided on the circuit board provided on the upper case and the lower case. A conductive elastic plate member is interposed between the body and a flexible substrate for connecting the circuit boards provided in both cases to each other and is pressed and supported on the inner surface of the case so as to be covered by the elastic plate member. A small printer characterized by that.