JPS5917952B2 - Electrode delivery device for multiple electrode printing heads - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a wire delivery device for a multi-wire print head, and more particularly to a device for delivering electrode wires for a metal paper printer to compensate for wear of the electrode wires.

The problem of electrode wear is particularly noticeable in metal paper printers, especially high resolution metal paper printers with narrow printed electrodes.

In order for the print head to maintain constant operating characteristics,
The electrode must be allowed to advance over time to compensate for its wear. Applicants have previously suggested very high resolution multi-electrode printheads in which the electrodes are advanced by a plurality of contact rollers.

However, in such conventional configurations, when a large number of electrodes are required for high-resolution printing, the force distribution along the tangents of the two rollers becomes uneven due to the length of the rollers. There were 5 flaws that made me feel bad.

Another drawback was that these rollers were slightly bent. Therefore, the force that restrains the electrode from moving forward is lower in the middle area of the roller than in the edge area. This drawback precludes the use of contact roller solutions in the case of a large number of electrodes. An object of the present invention is to provide an electrode delivery device that can advance a plurality of electrodes uniformly.

Another object of the present invention is to provide an electrode delivery device that can reduce the length of the electrode delivered by one stepwise movement of the driving means.

In order to achieve these objects, the present invention forms a plurality of parallel grooves on at least one of the outer circumferential surface of the drum and the inner circumferential surface of the casing that houses the drum, and provides electrodes in these grooves. is accommodated, and the drum driving means is engaged near the outer peripheral surface of the drum.

FIG. 1 shows a schematic perspective view of a device with an electrode drum, a drive element and a printing head.

The drum 2 itself has a flat front surface, and a groove 3 on the other side as shown in FIGS. 3 and 4, and a helical bevel gear (external bevel gear) 13 for driving The outer surface of the electrode drum 2 is provided with several parallel grooves 3, as shown in FIGS. 3 to 6.

The grooves 3 have a spacing that corresponds to the spacing of the electrodes 4 of the printing head 7. The number of grooves 3 thus corresponds to the number of electrodes of the printing head 7. In the example, only four electrodes are shown instead of multiple electrodes for ease of understanding. Electrode drum 2 is housing 1
The electrodes 4 in the grooves 3 of the six-electrode drum 2 are advanced towards the printing head 7. Electrode drum 2
A threaded mandrel 1 is mounted on the drive shaft 11 to drive the
2 is provided, which is engaged with the external bevel gear on the side of the above-mentioned inclined surface of the electrode drum 2. , the drive shaft 11 is automatically driven via an electromagnetic drive 9 of conventional design. As soon as a predetermined amount of wear on the printing head portion of the electrode 4 has been reached, a so-called sensing electrode (not shown) generates a signal which acts on the electromagnetic drive 9 to advance the electrode 4 automatically. When this signal is obtained, the armature of the electromagnetic drive unit 9 is energized and the electrode drum 2 starts to move forward. The stroke path of the magnetic armature may be variable and adjusted using conventional techniques to provide a constant amount of electrode advancement. The motion of the magnetic armature is transferred to the drive shaft 11 via a switch mechanism (not shown). The drive shaft 11 is provided with a blocking element (not shown) in order to avoid unwanted return movement. Pulse-controlled electromagnetic step mechanisms are known in the art and will not be described here. The drive shaft 11 is provided with a threaded axle 12 that engages with a helical bevel gear 13 of the electrode drum 2 . When a forward pulse is obtained, the electrode drum 2 is moved a predetermined amount according to the stroke path of the magnetic armature, and the electrode 4 is advanced in the direction of the printing head 7. The electrode drum 2 will be explained in detail below.

As mentioned above, the electrode drum 2 is particularly designed as shown in FIG.
5 sea urchin. It has several parallel grooves 3 on its outer surface. Each groove 3 has a hollow hole 5 into which a wire-shaped electrode 4 is inserted. For geometrical reasons, all the cutouts 5 in the individual grooves 3 are arranged obliquely. Therefore, even though the grooves 3 are close to each other, the cutouts 45 are sufficiently separated from each other. The end of the wire-shaped electrode 4 inserted through the cutout hole 5 is bent toward the distal side of the electrode drum 2 and guided through the insulating tube to the contact plug 6. The wire-shaped electrode 4 bent inside the drum 2 is fixed to the inner surface of the electrode drum 2 by a locking plate 14 that conforms to the curved surface of the electrode drum 2.

This locking plate 14 can be fixed to the wall of the electrode drum 2 by screws or other suitable fastening means. The wire-shaped electrode 4 in the groove 3 of the electrode drum 2 follows almost only one plane into the groove 3.

These surfaces are tangentially adjacent to the grooves 4 and are applied to the individual electrode positions of the printing head 7 by separate guiding devices, as shown in FIGS. 1, 6, 3 and 5. For this reason,
A recess 17 is provided in the upper part of the housing 1. This dent 17
The role of is to receive the printing head 7 and the cover wave 18. The position of the recess 17 is selected such that the electrode 4, which is held in one direction in the groove 3 of the electrode drum 2, is guided in the groove 19 provided in the surface 20 of the recess 17. These grooves 19 are also provided at intervals corresponding to the groove intervals of the electrode drum 2. In order to prevent the electrode 4 from coming off from these grooves 19, the surface 20 with the grooves 19 is covered with a flat cover plate 18.
covers. It may be fixed to the body of the housing 1 by a groove or other suitable fastening means. A printing head 7 with individual electrode guides is arranged in the body of the housing 1 in such a way that the electrode guides are aligned with the grooves 19. When the electrode drum 2 is moved in the direction of the arrow (FIG. 2), this advances the electrodes 4 in the direction of the printing head 7. It can be seen from FIGS. 2 and 5 that the electrode drum 2 is supported within the circular opening 16 of the housing 1 with high tolerances due to its cylindrical shape. The plurality of linear electrodes 4 in the grooves 19 of the electrode drum 2 are fixed in their respective positions by the wall of the circular opening 16 of the housing 1 that holds the electrode drum 2, and will not be deviated. Locking plate 1
4 has a protrusion 2 protruding from the surface of the electrode drum 2 (Fig. 7).
1 is provided.

This figure 7. The part where you want to display the details of Figure 4
7, a partial sectional view of the protrusion 21 of the locking plate 14 placed in the guide passage of the housing 1 is shown. This partial view shows how the electrode drum 2 is locked. In Figure 4 [
FIG. 7, which shows the details of "7", shows that the protrusion 21 of the locking plate 14 moves within the guide passage 15 of the housing 1. This feature ensures that the electrode drum 2 is guided within the housing 1 and avoids shifting of the electrode drum 2 from the circular opening 16 of the housing 1. FIG. 6 shows a partial cross-sectional view showing the electrodes 4 in the grooves 19 of the electrode drum 2, according to the section "6" in which the details of FIG. 4 are intended to be displayed.

The grooves 3 on the outer surface of the electrode drum 2 exhibit a substantially triangular cross section for arranging the electrodes 4. The electrode 4 is prevented from deviating from the groove 19 by the wall of the housing 1. As a variant of the embodiments shown in the drawings, the grooves 19 for the electrode passages may be provided not on the outer surface of the electrode drum 2 but on the inner surface of the circular opening 16, or both.

In such a configuration, since the grooves 3' and 19 are provided in the same housing 1, no shift of the electrode 4 will occur during its insertion into the groove 19 of the recess 17. Even in this configuration, the electrode 4 is fixed to the inside of the electrode drum 2 by the locking plate 14 as shown in FIG.

[Brief explanation of the drawing]

FIG. 1 is a schematic perspective view of the housing with the electrode drum, drive elements and printing head. 2 is a schematic front view of the arrangement according to FIG. 1; FIG. Third
1 is a schematic plan view of the arrangement according to FIG. 1; FIG. Figure 4 is line 4 in Figure 1 to show the electrode drum in a partial cross-sectional view of the housing.
-4 is a schematic plan view taken along 4. FIG. 5 is a schematic cross-sectional view taken along line 5--5 of FIG. 3 to show the housing with the drum. FIG. 6 is a partial cross-sectional view detailing portion "6" of FIG. 4 to show the electrodes extending into the grooves of the electrode drum. FIG. 7 is a partial cross-sectional view showing a protrusion of the locking plate extending into the guide passage of the housing. 1... Housing. 2... Electrode drum, 3... Groove, 4...
·····electrode. -5...Drilled hole. 6...
...Contact plug, 7...Print head, 16
......Circular opening, 19...Groove.

Claims (1)

[Claims] 1. A hollow drum, a housing housing the drum, parallel grooves provided on at least one of the outer peripheral surface of the drum and the inner peripheral surface of the housing to accommodate a plurality of electrodes, and the drum. A through hole provided in the drum for guiding the electrode to be connected to the contact plug on the inner peripheral surface of the drum, and an electrode disposed in a groove on the peripheral surface are printed along the tangential direction of the peripheral surface. An electrode delivery device for a multi-electrode printing head comprising means for guiding the electrodes to the head and drive means engaged near the outer circumferential surface of the drum to rotate the drum in steps for delivering the electrodes.