JPS5921013Y2 - Print head position adjustment device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a print head position adjustment device in a serial printer or the like.

The print head in an impact dot printer defines dots by driving the print element facing the platen in small strokes at high speed, and forms characters etc. with an appropriate dot pattern. It is placed fairly close to the printing surface.

If the distance between the tip of the printing element and the platen is not within the specified range, it may result in unstable response, poor printing, or an excessive load on the printing element drive mechanism, resulting in abnormal wear or This causes fatigue and shortens the life of the print head.

For this reason, it is necessary to adjust the distance between the printing element and the platen within a predetermined range.

In addition, in this type of printer, recording paper of a constant thickness is not always used, and there are cases where several sheets of recording paper are printed on top of each other (for example, when printing slips, etc.), and the print head is adjusted each time. Position adjustment is required.

However, the conventional apparatus has a drawback that it is difficult to make accurate adjustments to suit the thickness or number of recording sheets unless the person is familiar with the mechanism.

The present invention is based on Utility Application No. 52-23711 (1983) filed by the applicant.
This is a print head position adjustment device disclosed in Japanese Utility Model Application No. 53-120108) which has been further improved to eliminate the above-mentioned drawbacks, and one embodiment thereof will be described below with reference to the drawings.

In FIG. 1, a print head 1 is connected to a support plate 2 having an angled cross-section.
is attached to.

This print head 1 is of a moving coil type, and its basic configuration is a print lever 3 whose lower part is fixed to a support plate 2, and a print lever 3 provided at the free end of the upper part and spaced apart from the platen 4 at a predetermined distance. The printing element 5 facing each other, the moving coil 6 fixed near the center of the back of the printing lever 3, the magnetic flux generating unit 7 that generates magnetic flux across the moving coil 6, and the magnetic flux generated at the back of the upper part of the printing lever 3. The ink ribbon guide 8 is fixed to the generator 7.

Although not shown, as is well known, a recording paper and an ink ribbon are inserted into a minute gap between the platen 4 and the printing element 5.

Then, by selectively applying a pulsed current to the moving coil 6, the moving coil 6 receives an impactful displacement force toward the platen 4 in cooperation with the magnetic flux of the magnetic flux generator section 7, and the printing lever 3 is oscillatingly displaced to the left using the support portion as an indicator, so that a dot is formed by the printing element 5.

The detailed structure and operation of this print head 1 will be omitted as they are not directly related to the present invention, but are disclosed in detail in Japanese Patent Application No. 1983-119506 "Impact Type Dot Printer" filed by the present applicant.

Further, the print head 1 is not limited to the above system and structure.

The support plate 2 has an upper bent portion 2a attached to the member 9 so as to be adjustable in position with the following structure.

The member 9 is a carriage (not shown) that is scanned in a direction perpendicular to the paper feeding direction of the recording paper (upper side in FIG. 1).

) and moves together with this carriage.

Of course, this member 9 can also be part of the carriage itself.

As shown in FIGS. 1 to 3, the member 9 has a large threaded portion 1.
0 a and a small screw part 10 b on the upper part of the screw 1
0 is fixed to the vertically bent portion 2a of the support plate 2 through a fitting hole 11 drilled in the center of the center of the support plate 2.

A position adjustment nut 12 is screwed into the large screw portion 10a.

The position adjustment nut 12 has many triangular shapes (
In this embodiment, 20 pawls 12a are formed at equal intervals, and a flat conical surface i2b is further formed at the bottom.

The position adjusting nut 12 also has a screwdriver groove 12C on its upper surface.

As shown in the second figure, small holes 13 are formed on both sides of the vertically bent portion 2a.
13 is formed, and a spring (not shown) is hooked into this small hole 13.13.

), the support plate 2 (print head 1) is urged in the direction of the arrow in FIG. 1 (diagonally backward).

Therefore, the conical surface 12b of the position adjustment nut 12 and the fitting hole 11 are in contact with each other at the front to position the print head 1, and there is a gap at the rear.

Further, a locking nut 15 is screwed into the small screw portion 10b by inserting a fine adjustment lever 14 which is rotatable around the small screw portion 10b.

The fine adjustment lever 14 is made of a spring material, and has a thin retaining piece 14a bent at right angles at one end thereof and capable of being retained between the claws 12a of the position adjustment nut 12.
A click member 16 is fixed to the other end.

The click member 16 has a click protrusion 16 at its lower part.
a is formed, and the upper part thereof is a knob 16b.

The design of the click member 16 may be changed so that it is formed integrally with the other end of the fine adjustment lever 14.

On the other hand, as shown in FIG. 3, the upright bent portion 2a of the support plate 2 has a plurality of ( In this embodiment, there are three click holes 17a,
17b and 17C are formed, and the click member 16
The protrusion 16a of these holes 17a, 17b,
17C and is stably fitted into the position.

Furthermore, in FIG. 2, the member 9 has two guide pins 1.
8 is planted, and a guide pin 18 is installed in the vertically bent portion 2a.
Two guide grooves 19 are provided in which the guide pins 18 and the guide grooves 19 can slide, and the print head 1 is aligned perpendicularly and parallel to the platen 4 through a guide means composed of these guide pins 18 and guide grooves 19. It is movable.

Next, the position adjustment operation of the print head will be explained.

To adjust the position of the print head 1 at the factory, remove the stop nut 15 and remove the fine adjustment lever 14, or use the engagement piece 14a of the fine adjustment lever 14 and the claw part 12 of the adjustment nut 12.
Turn the adjusting nut 12 while loosening the locking nut 15 until it is disengaged from the locking nut 15.

By turning the adjusting nut 12, it is displaced upwards or downwards.

At this time, since the print head 1 is pushed by the spring in the direction of the arrow in FIG.
The contact position between the two changes while always being in close contact with the conical surface 12b of the print head 1, and the print head 1 moves forward or backward relative to the platen 4, and this operation causes the print head 1 to move forward or backward relative to the platen 4.
is aligned with the platen 4 at a predetermined position.

As shown in Figure 2.3, the fine adjustment lever 14 is engaged with its click member 16 (protrusion 16a), for example, in the leftmost click hole 17a, and the locking nut 15 is tightened.

Even when the locking nut 15 is screwed on, the fine adjustment lever 14 can rotate around the screw 10 (small screw portion 10b).

The above-mentioned position adjustment of the print head 1 is generally performed using general-purpose recording paper (the thickness of which is usually about 0.07 to 0.1 mm).

), and the product is sold to users in this state.

By the way, from the pitch of the adjusting nut 12 (or the large threaded portion 10a) and the taper angle of the conical surface 12b, the amount of movement of the print head 1 relative to the rotation angle of the adjusting nut 12 can be calculated, and based on this, the amount of movement of the print head 1 can be calculated. 17a,
17b and 17C are bored at appropriate angular intervals.For example, when the fine adjustment lever 14 is rotated from the click hole 17a to the click hole 17b or 17C in FIG. The engagement piece 14a is the claw part 1
2a, the adjustment nut 12 also rotates counterclockwise following the rotational movement of the fine adjustment lever 14, the fine adjustment nut 12 is displaced upward, and the print head 1 is rotated in advance. Displaces to the right by the set amount.

That is, as an example, the fine adjustment lever 14 may be inserted into the hole 17b.
By turning the fine adjustment lever 14 to the hole 1 position, the position of the print head can be finely adjusted to accommodate two sheets of general-purpose recording paper stacked or thick recording paper approximately corresponding thereto.
When turned to the 7C position, the position of the print head is finely adjusted to accommodate three sheets of general-purpose recording paper, or even thicker recording paper that corresponds thereto.

According to the print head position adjustment device according to the present invention described in detail above, fine adjustment of the print head position corresponding to the number of sheets of recording paper used or the thickness of the recording paper can be carried out extremely easily and extremely accurately. Therefore, the user can easily make this fine adjustment of the position by himself/herself without having to dispatch a service person from the manufacturer.

Furthermore, periodic adjustment services to deal with wear and tear on printing elements can be performed easily and quickly.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention, in which Fig. 1 is a side view showing a cross section of the main part, Fig. 2 is a plan view, and Fig. 3 is a plan view.
The figure is a sectional view taken along the line III--III in FIG. 2. DESCRIPTION OF SYMBOLS 1... Print head, 2... Support plate, 9... Member,
DESCRIPTION OF SYMBOLS 10... Screw, 11... Fitting hole part, 12... Adjustment nut, 12 a... Claw part, 12b... Conical surface, 1
4... Fine adjustment lever, 14 a... Engagement piece, 16.
17a, 17b, 17C...Clicking means, 18°19...Guiding means.

Claims (1)

[Claims for Utility Model Registration] A member that is scanned in a direction perpendicular to the feeding direction of recording paper; a print head mounted on the member; In a print head position adjustment device, the print head position adjustment device includes a guide means that is movable in a direction, a positioning means that determines a relative positional relationship between the member and the print head, and a spring that biases the print head rearward. the positioning means includes: a screw fixed to the member and protruding through a fitting hole formed in the support plate for the print head; a position adjustment nut having a conical surface that connects with the mating hole; a large number of pawls formed at equal intervals on the outer periphery of the position adjustment nut; rotatable about the screw; and The fine adjustment lever includes a locking piece that engages between the claws, and click means that stably locks the fine adjustment lever at a plurality of positions substantially equiangular with respect to the rotation center of the fine adjustment lever. A print head position adjustment device characterized by: