JPH0450128Y2 - - Google Patents

Description

[Detailed Description of the Invention] Technical Field of the Invention The present invention relates to a grounding mechanism for preventing static electricity in a printer.

Prior Art A type of printer is being developed in which fanfold paper is introduced into the printer from the bottom of the printer body and is pushed through a printing mechanism by a pin tractor mechanism to print.

In such printers, since the pin tractor mechanism is located inside the printer body, it is difficult to load fanfold paper into the printer first, and for this purpose, the printer body must be attached to the upper and lower housings. The upper housing is pivoted so as to be swingable from the closed position to the open position in which the upper housing is swung upward, and the fanfold paper introduced from the lower housing to the upper housing is held in the open state of the upper housing. A space formed between the upper housing and the lower housing is used to expose part or all of the pin tractor mechanism in this space, thereby making it easy to load fanfold paper into the pin tractor mechanism. This was proposed by the present applicant as Utility Application No. 1983-4746.

Disadvantages of the Prior Art In the above-mentioned printers, the main body of the printer's printing mechanism is usually arranged in the upper housing, and the main body of the control circuit is arranged in the lower housing. The grounding path for the lower housing that must be provided in order to ensure the proper operation of the printing mechanism located inside the housing is inevitably long, which causes static noise, which can cause malfunctions in, for example, the LED display of a printer. The negative effects of electrostatic noise, such as those caused by electrostatic noise, were more likely to occur. For this reason, relatively expensive, highly conductive plating is applied to the main chassis bracket of the upper housing and its shaft support.
Efforts have been made to increase the conductivity between the bracket and the chassis side of the lower housing by applying conductive grease to the shaft support, but there are many uncertainties regarding the generation of static noise, so it is necessary to use the shortest possible grounding route. It was hoped that he would take this.

Purpose of the Invention The present invention aims to eliminate the drawbacks of the above-mentioned prior art and provide a highly reliable grounding mechanism for electrostatic countermeasures in a printer having an upper housing that is swingable relative to a lower housing. purpose.

Summary of the invention In order to achieve the above-mentioned purpose, the grounding mechanism for electrostatic countermeasures for a printer according to the invention is such that the main body of the printer's mechanism is placed in an upper housing that can swing relative to the lower housing, and In a printer in which a main body of a control circuit is arranged, an elastic grounding plate having a comb-like bent arm is attached to the chassis of the lower housing, and when the upper housing is closed, the elastic grounding plate connects to the main chassis of the upper housing. It is characterized in that it makes elastic contact and thereby performs earthing.

With this configuration, in the grounding mechanism according to the present invention, the chassis of the upper housing and the lower housing that are close to each other in the closed position are directly connected by the elastic grounding plate, and grounding can be performed over the shortest distance. This provides a highly reliable electrostatic noise countermeasure.

Embodiments of the invention Preferred embodiments of the invention will be described below with reference to the drawings.

FIG. 1 shows a preferred embodiment of a printer incorporating the grounding mechanism of the present invention, which includes an upper housing 1 and a lower housing 2. As shown in FIG. The upper housing 1 has a main chassis 3, on which a pair of brackets 4 are formed on both side edges, and a lower housing 2.
Pivot shafts 5 mounted on the brackets 4 extend through holes formed in these brackets 4, thereby allowing the upper housing 1 to be moved relative to the lower housing 2 into the closed position shown in FIG. 1 and in the closed position shown in FIG. It is made swingable between the shown open position and the open position. A stand 6 is arranged below the lower housing, and an insert formed in the bottom wall 2a of the lower housing is provided with a fanfold paper 7 pulled out from a stack 8 of fanfold paper 7 arranged inside the stand 6. It is adapted to be guided into the lower housing 2 through the opening 2b. The fanfold paper 7 introduced from the insertion opening 2b passes through the insertion opening 3a formed in the main chassis 3 of the upper housing 1 and is moved by a pin tractor mechanism 9 installed so that a part of it protrudes below. The fan fold is adapted to be pushed into the upper housing 1 (the entire pin tractor mechanism mechanism 9 may protrude toward the lower housing 2 side), and the fan fold that is pushed in this way The paper 7 is guided by a paper guide 10 to a print head 11 that constitutes a printing mechanism.
and a platen 12 to perform printing.

Pin tractor mechanism 9 is fanfold paper 7
A pair of perforation paper 7 is provided so as to engage with and feed the perforations on both sides of the perforation paper 7, and are guided by a drive shaft 13 and a guide shaft 14 parallel to each other as is well known. The spacing between the perforations can be adjusted to match the spacing of the perforations on both sides. Each pin tractor mechanism 9 is stretched around a tractor frame 15, a rotary body on a drive shaft 13, and a support body on a guide shaft 14 parallel to this, and is rotated by the drive of the drive shaft 13. It consists of an endless pin belt formed with a perforation engagement pin 16, a presser plate 17 pivotally fixed to the tractor frame 15, and the like.
As shown in the figure, there is a pin relief groove 17a, and as shown in FIG. 2, there is sufficient space between the upper housing 1 and the lower housing 2 when the upper housing 1 is in the open position When the presser plate 17 is opened using this space, the perforation of the fanfold paper 7 can be easily engaged with the pin 16 of the pin tractor mechanism 9. When the perforation 7 is engaged with the pin 16 and the presser plate 17 is closed to ensure the engagement between the pin 16 and the perforation, the upper housing 1 is opened as shown in FIG. When it is swung to the closed position, the fanfold paper 7 can be fed by the operation of the pin tractor mechanism 9. The print head 11 is supported on a carriage 19 that is slidably supported in a reciprocating manner by a pair of guide shafts 18, 18 parallel to the drive shaft 13, and is adapted to be reciprocated along the platen 12. ing. The operation of the pin tractor mechanism 9, the print head 11 and the platen 12 are synchronously timed to each other, e.g.
It is designed to be controlled by a control circuit (not shown), a portion of which is disposed within the chassis 20. Note that 21 is a bail roller, and paper guides 22, 22 are arranged around the platen 12 to guide the cut paper around the platen 12 in cooperation with a friction roller 23 for printing. It's getting old. The printed fanfold paper 7 is drawn out from a delivery opening 1b formed in the top wall 1a of the upper housing 1.

A feature of the present invention is a grounding mechanism that allows the printing mechanism in the upper housing 1, which is swingable to the open position, to be grounded to the lower housing 2 over the shortest distance.

That is, an opening 20a is formed in the top wall of the chassis 20 of the lower housing 2, and a comb-like shape as shown in FIGS. 3 and 4 is formed on the upper surface of one edge of the opening 20a in the top wall. Multiple bending arms 25
Base 25b of conductive elastic ground plate 25 with a
is attached, and the elastic earth plate 25 itself is elastically biased upward, but the bent free end 25c of the bending arm 25a is connected to the opening 20.
The ground plate 25 is inserted into and locked under the other end edge of the plate a, thereby preventing the elastic grounding plate 25 from flying upward due to the elastic biasing force. In this restrained state, the bending arm 2
The bent top portion 25d of the lower housing 2 is positioned so as to protrude above the top surface of the lower housing 2, as shown in FIG.

With this configuration, in the printing position where the upper housing 1 is swung to the closed position, the bent top portion 25d of the elastic grounding plate 25 is brought into contact with the main chassis 3 on the upper housing 1 and is The upper housing 1 is pressed downward against the elastic force, and the upper housing 1 can be grounded to the lower housing 2 by the shortest distance.

Effects of the Invention As described above, according to the present invention, an elastic ground plate is simply provided on the chassis of the lower housing of a printer having an upper housing that is swingable relative to the lower housing, and the upper housing is swung to the closed position. Sometimes, simply having it elastically abut against the main chassis of the upper housing has the advantage of providing a shortest distance grounding mechanism that can provide very good grounding performance.

[Brief explanation of the drawing]

Fig. 1 is a cross-sectional view of a printer incorporating an embodiment of the grounding mechanism of the present invention in a closed position, Fig. 2 is a cross-sectional view of the printer of Fig. 1 in an open position, and Fig. 3 is a cross-sectional view of an elastic grounding plate. A plan view, and FIG. 4 is a side view of FIG. 3. 1... Upper housing, 2... Lower housing, 3... Main chassis, 6... Stand, 7
...Fanfold paper, 8...Stack, 9...
...Pin tractor mechanism, 11...Print head, 1
2... platen, 20... chassis, 25... elastic ground plate.

Claims (1)

[Scope of utility model registration request] It consists of an upper housing in which the main mechanism of the printer is mounted, and a lower housing in which the main control circuit is arranged. an opening in the bottom wall of the lower housing for exposing at least a portion of a pin tractor mechanism disposed in the upper housing into a space formed between the housing and the lower housing when the housing is open; It is easy to load the fanfold paper introduced from the pin tractor mechanism into the pin tractor mechanism, guide it to the main body of the printer mechanism in the upper housing, and remove the printed fanfold paper from the opening provided in the top wall of the upper housing. In a printer of a type that discharges old paper, one end of an elastic grounding plate having a comb-like bent arm is attached to the chassis of the lower housing at a position remote from the pivot portion, and when the upper housing is in the closed position. the bending arm is configured to elastically contact the main chassis of the upper housing through an opening formed in the lower housing, and the other free end of the elastic ground plate is prevented from protruding upward from the lower housing. A grounding mechanism for preventing electrostatic discharge in a printer, characterized by being provided with a locking means for preventing static electricity.