JPH0432744B2 - - Google Patents

Abstract

Such a matrix printer head with adjustable print wire guide (23), comprising a print wire drive assembly (2), arranged on the side remote from the print abutment (1), and a print wire adjustment assembly (3) facing the print abutment (1), is provided with a print wire adjustment drive (4). In order to permit the writing of letter-quality print by writing twice over one and the same line in oppositely running print passes with the required accuracy, a matrix printer head is provided in which, on the one hand, an adaptation of the print wire adjustment assembly (3) to the available print wires or their guides takes place and, on the other hand, the matrix printer head can be set extremely accurately with regard to the wire stroke, i.e. the advancement of each individual print wire, and with regard to the stroke length in the adjusting of the print wire guide (23), this extremely accurate setting being achieved by the print wire drive assembly (2) and the print wire adjustment assembly (3) in each case being arranged in a separate housing (5) and (15) respectively, by the two housings (5 and 15) being connected releasably to each other and by the print wire adjustment drive (4) being arranged so as to run approximately in the direction of the print wires (6) in the housing (15) of the print wire adjustment assembly (3). <IMAGE>

Description

[Detailed Description of the Invention] (a) Industrial Application Field The present invention comprises a printing needle drive mechanism disposed on the side remote from the print support, and a printing needle adjustment mechanism located facing the print support. The present invention relates to a matrix print head with an adjustable printing stylus guide comprising a printing stylus adjustment mechanism with a drive.

(b) Prior Art Matrix print heads of this type with adjustable printing stylus guides are used for printing rapid and/or beautiful characters. In the case of quick characters, printing is performed line by line from left to right and then from right to left without changing the position of the printing needle guide, whereas in the case of beautiful characters or beautiful characters that are printed relatively quickly, In this case, printing is performed by repeatedly printing one and the same line using reverse printing passes while adjusting the printing stylus guide. In this case, one needle row is composed of, for example, seven to nine needles. According to an arrangement of this type, seven printing needles can be arranged one above the other, one above the other, as long as there is structurally available space in the matrix print head.
It goes without saying that it is possible to provide a plurality of adjacent rows of nine needles arranged from a book.

Such a matrix printing head with an adjustable printing stylus guide is already known (DE 26 32 293). This known print head has two rows of equally spaced print wires which are vertically movable. Known matrix
In the print head, the print wires of the print needle row are mounted on support elements, one of which is fixed to the print head saddle and the other with a leaf spring at its upper end. It is arranged so that it can be moved in the vertical direction via a cam that is operated electromagnetically or manually while being held.

Furthermore, only one printing needle row consisting of nine printing needles is provided in the matrix print head, and in order to print beautiful characters, the mouthpiece, that is, the printing needle guide is moved a distance of "X" (from left to right). It is also known to adjust in a laterally moving printing path (from right to left) and to vary the spacing of the matrix electronically in the line direction in conjunction with this adjustment (cf. German Published Patent Application No. 30 41 877). . The gist of this known matrix print head is that it is provided with two printing needle guides whose heights can be adjusted relative to each other, but in many cases, the printing needle guides are arranged at a predetermined position. Since two electromagnets are required to guide the matrix to the position of
This is made clear from examples of conventionally known configurations of print heads. Another disadvantage of the known design is that it is very wide, since it provides a print needle guide in the area of the print support, i.e. in the position where the characters are to be printed, in the matrix print head. Because of this, it is difficult to visually see the matrix print head, which prints well, and the matrix print head is relatively heavy and requires 9 or 18 printing needles in conjunction with the printing needle adjustment mechanism. It is very difficult to install them at the same time due to the structure.

(c) Problems to be solved by the invention Therefore, an object of the present invention is to adapt the printing needle adjustment mechanism to an existing printing needle or printing needle guide, and to adjust the stroke of the printing needle, that is, each The matrix print head can be accurately adjusted in terms of the feed of the printing needle and the height when adjusting the printing needle guide, thereby ensuring the desired quality of beautiful characters. The goal is to provide a head.

(d) Means for solving the problem The above problem consists of a printing needle drive mechanism that drives the printing needle and a printing needle adjustment mechanism that adjusts the printing position of the printing needle, and the printing needle adjustment mechanism adjusts the printing position. It has a needle adjustment drive, an armature member whose position can be adjusted by the print needle adjustment drive, and a print needle guide fixed to the end of the armature member facing the print support. However, in the matrix print head, the position of the printing stylus guide can be adjusted in the vertical direction by moving the armature member within the air gap between the printing stylus adjustment drive and the armature member. An electromagnetic coil 20 is placed inside the casing 15 of the drive mechanism 4.
are arranged substantially in parallel along the longitudinal direction of the armature member 19, and at the end of the electromagnetic coil 4 on the printing needle guide 23 side, the armature member 19 is located between the metal magnet core 36 of the electromagnet of the printing needle adjustment drive mechanism. , an air gap 37 is formed to determine the amount of movement of the armature member, and the end of the armature member 19 on the printing needle drive mechanism 2 side is rotatable so as to form a magnetic path with the metal magnet core 36. The solution is a matrix print head with an adjustable printing needle guide, which is characterized in that it is connected.

According to the invention, the adjustment drive for adjusting the printing stylus guide can be adapted to the shape of the casing of the matrix print head.
There is no difficulty in the structure when extending the printing needle for a long time as usual. Furthermore, since the casings of the printing needle drive mechanism and the printing needle adjustment mechanism are separated, when the printing surface of the printing needle becomes worn and the length of the printing needle needs to be readjusted, the length of the printing needle can be readjusted. This is advantageous because it can be easily performed.

Moreover, since the electromagnetic coil 20 is arranged substantially parallel to the longitudinal direction of the armature member 19 extending in the longitudinal direction of the printing needle, the structure is compact and can be accommodated within the casing 15. Moreover, since it is housed within the casing 15, the electromagnetic coil 20 is reliably protected.

Furthermore, according to a preferred embodiment of the invention:
By providing a replaceable pad between the casing of the printing needle drive mechanism and the casing of the printing needle adjustment mechanism, it is possible to adjust the length of the printing needle whose length has been worn out unevenly. As such a pad, for example, a distance plate is used which has a thickness equal to the readjustment distance or the amount of wear of the printing stylus.

Printing is performed using an armature member extending in the length direction of the printing needle, an electromagnetic coil extending parallel to the armature member, an end support supporting the armature member, and a fixing device fixing the armature member. By configuring the stylus adjustment mechanism and securing the print stylus guide to the front end of the armature member, the configuration and dimensions of the print stylus adjustment device can be closely matched to the configuration of the matrix print head. Although it can be adapted to the extending structure of nine printing needles and a plurality of printing needle rows extending in the length direction and having the armature members arranged vertically in order, the matrix print head The height is only slightly higher than the conventional one. Furthermore, it is advantageous to incorporate the electromagnetic coil longitudinally and to provide the required adjustment distance to the printing stylus guide based on the above-described basic arrangement of the armature members.

According to another embodiment of the invention, it has been proposed that the armature member is constituted by a metal lever, said lever being rotatably supported in the region facing the printing needle drive mechanism. In this embodiment, the printing stylus guide can be adjusted a predetermined distance by only slightly tilting it. In addition,
The radius of rotation of the tilting movement is dimensioned so large that the bending movements occurring in the printing needle guide are so small as to be negligible.

In addition, the printing guide is securely fixed in the selected upper or lower adjustment position by moving the armature member in both adjustment directions of the printing needle under the action of the elastic force of one or more springs. I can do it.

Furthermore, the idea of the invention is to bias the armature member by means of a flexure spring in the region of the printing stylus drive mechanism and by means of a compression or tension spring in the region facing the print support. It was proposed in accordance with the practical aspects of The electromagnet overcomes the corresponding force of the spring, but in this case the deflection spring limits the exact extent of rotation of the armature member about the rear end support.

In addition, by arranging the armature member between the side guides, the accuracy of the above-mentioned tilting movement can be improved. This side guide allows the armature to be supported easily and with less wear.

According to another embodiment of the invention, it has been proposed that the electromagnet has a metallic magnetic core, which cooperates with the armature member to form an air gap. This embodiment makes it possible to limit the air gap very precisely, thereby significantly reducing flux losses, and thus keeping the current required to energize the electromagnetic coils low. At the same time, it is possible to prevent the matrix print head from heating up above an acceptable level. As is known, the matrix print head is equipped with a separate electromagnetic coil within the print stylus drive mechanism for operating each print stylus, which inevitably increases the temperature of the matrix print head to some extent. A particularly serious problem is the heating of matrix print heads above acceptable levels.

According to another embodiment of the invention, it has been proposed to provide a metallic magnet core within an electromagnetic coil made of an insulating material. According to this configuration, the supporting portion of the magnetic core can be formed to fix the magnetic core, so that the magnetic core is hardly displaced and moreover, stray loss of magnetic flux can be avoided.

It has also been proposed according to a further embodiment of the invention that the magnetic core of the electromagnetic coil forms an end support of the armature member in the region facing the printing stylus drive mechanism. With this configuration, it is possible to obtain the required magnetic circuit without requiring a large amount of space for the structural support of these components and without the risk of causing very large stray losses.

It has also been proposed according to another embodiment of the invention that the air gap between the magnet core and the armature member can be adjusted by means of an adjustment bolt mounted on the casing of the printing needle adjustment mechanism. . This feature is very important for printing beautiful characters by accurately adjusting the stroke of the printing needle guide between the two printing processes, that is, before the forward printing process or the backward printing process. .

By constructing a fixing device for fixing the armature member from a stopper for limiting the adjustment distance of the printing needle guide and a means for adjusting the air gap,
The work of adjusting the printing needle guide according to the adjustment distance of the printing needle guide can be improved. This configuration makes it possible to set the end position of the printing stylus guide very precisely and to make very precise adjustments to the printing lines in the actual use of the matrix printer. It is possible.

Furthermore, it is advantageous in terms of manufacturing technology that the printing needle adjustment mechanism is made of plastic and that the magnetic core of the electromagnetic coil is ultrasonically welded to the housing projection. This construction measure simplifies the fixing of the metal magnet core of the electromagnetic coil and makes it possible to dispense with special fixing means.

(E) Embodiments and Effects The present invention will be described in detail below with reference to the accompanying drawings illustrating embodiments of the present invention.

A matrix print head with an adjustable printing stylus guide is arranged opposite a print support 1, which is designed as a platen. The matrix print head according to the present invention is composed of a printing stylus driving mechanism 2 and a printing stylus adjusting mechanism 3. Print needle adjustment drive device 4
The configuration will be explained in detail later. The printing needle drive mechanism 2 is surrounded by a casing 5, and includes an electromagnetic coil 7 provided for each printing needle 6, a yoke main body 8, an armature plate 9, and an abutment piece 10.
, a printing needle head 11 , a return spring 12 , and a printing needle support member 13 are housed therein. The structure of the printing needle drive mechanism 2 whose purpose is to print printing points on the display paper 14 by operating the printing needle 6 is not a subject of the present invention. On the other hand,
It is essential in the present invention to fix the casing 5 to the casing 15 with the replaceable pad 16 interposed therebetween. Exchangeable bet 1
Inserting the printing needle 6 is the first step in accurately adjusting the printing needle 6. Note that if the length of the printing needle 6 is worn out in the area 17 of the print support 1,
Readjustment can be performed by removing one of the pads 16, and after the readjustment, the printing needle 6 is reground to the required length at the ruby 18 position.

A printing needle adjustment drive device 4 is provided in the main body 15 of the printing needle adjustment mechanism 3, and the printing needle adjustment drive device 4 extends in the length direction of the printing needle 6 substantially parallel to the printing needle 6. . By arranging it in this manner, the space for housing the printing needle adjustment drive device 4 can be saved, and it can be adapted to the elongated shape of the casing 15.

Furthermore, the printing needle adjustment mechanism 3 includes an armature member 19
, an electromagnetic coil 20 extending parallel to the armature member 19, an end support 21 supporting the armature member 19, and a fixing device 22 for the armature member 19, with the printing needle guide 23 at the front end. 19a. A ruby 18 is inserted through the tips of the nine printing needles 6 arranged in order in the vertical direction, and the ruby 18 is housed in the wall of the casing 15, and the armature member 19 is connected to the metal lever 24. The metal lever 24 is rotatably supported at its end 19b.
The metal lever 24 is adapted to move in one of the printing needle guide adjustment directions 25 and 26 under the action of the elastic force of a compression spring 27, and comes into contact with a stopper 28. The end 19b of the curved portion of the armature member 19 is accommodated in the recess 29, and the position of said end 19b is held by a flexure spring 30. A side guide 31 is provided so that the printing needle moves within a required plane.

The printing needle 6 is guided not only by a printing needle guide 23 but also by support surfaces 32, 33, and 34.

An insulated coil body 3 inside the electromagnetic coil 20
5 is provided, and a metal magnet core 36 is provided inside the coil body 35. The front end 36a of the magnet core 36 cooperates with the armature member 19 to form an air gap 37 which determines the amount of movement of the metal lever.

Since the armature member 19 is provided with the curved portion 19c, the deflection spring 30 can be smoothly engaged with the armature member 19. Magnet
The core 36 is a plastic casing protrusion 38
and is fixed by a fixing member 39 that is ultrasonically welded.

As a second step to improve the accuracy of the written image, an adjustment bolt 40 is attached to the casing 15 of the printing needle adjustment mechanism 3 in order to adjust the armature member 19 and the printing needle guide 23, By operating the adjustment bolt 40, the size of the air gap 37 and the printing needle guide 2 can be adjusted.
3 adjustment distance can be adjusted accurately. The coil body 35 is provided with a protrusion 41 which prevents stray losses in the magnetic flux in the magnetic circuit (consisting of the magnet core 36 and the armature member 19) due to the adjusting bolt 40 connected to the casing 15 made of plastic. will not occur.

[Brief explanation of drawings]

The attached drawing is a cross-sectional view of the printing needle drive mechanism and the printing needle adjustment mechanism cut in the axial direction. 1...Print support, 2...Print needle drive mechanism, 3...Print needle adjustment mechanism, 4...Print needle adjustment drive device, 5...Casing, 6...Print needle, 7
... Electromagnetic coil, 8 ... Yoke body, 9 ... Armature plate, 10 ... Contact piece, 11 ... Printing needle head,
12... Return spring, 13... Printing needle supporting member, 1
4...display paper, 15...casing, 16...
Pad, 18... Ruby, 19... Armature member,
20... Electromagnetic coil, 21... End support,
22... Fixing device, 23... Printing needle guide, 24
...Metal lever, 27...Compression spring, 28...
Stopper, 29...dent, 30...deflection spring, 31...side guide, 32, 33, 34...
Support surface, 36...Magnetic core, 37...Air gap, 38...Casing protrusion, 39...
...fixing member, 40...adjustment bolt.

Claims (1)

[Scope of Claims] 1. A printing needle adjustment drive device consisting of a printing needle drive mechanism that drives a printing needle and a printing needle adjustment mechanism that adjusts the printing position of the printing needle, and a printing needle adjustment drive device that adjusts the printing position by the printing needle adjustment mechanism; an armature member whose position can be adjusted by a needle adjustment drive; and a printing needle guide fixed to the end of the armature member facing the print support; In the matrix print head, the position of the printing needle guide can be adjusted in the vertical direction by moving the armature member within the air gap between the printing needle adjustment drive mechanism 4 and the armature member. The electromagnetic coil 20 is arranged substantially parallel to the longitudinal direction of the armature member 19,
At the end of the electromagnetic coil 4 on the printing needle guide 23 side, the armature member 19 forms an air gap 37 between it and the metal magnet core 36 of the electromagnet of the printing needle adjustment drive mechanism, which determines the amount of movement of the armature member. , the end of the armature member 19 on the printing needle drive mechanism 2 side is provided with an adjustable printing needle guide, which is rotatably connected to the metal magnet core 36 so as to form a magnetic path. Matrix
Print head. 2 Metal magnet core 36 of electromagnetic coil 20
is the area on the printing needle drive mechanism 2 side, and the armature member 19
1. A matrix printing machine equipped with an adjustable printing needle guide according to claim 1, characterized in that it forms a bearing part for supporting the printing needle guide.
Head. 3. The armature element 19 consists of a metal lever 24, which in the region facing the printing needle drive mechanism 2 is journalled without play by a flexible spring 30. A matrix print head with an adjustable printing stylus guide according to claim 1 or 2. 4. The armature member 19 is movable in the direction of the fixing device 22 by a spring 27 in a direction opposite to the direction of action of the magnetic force of the printing needle adjustment drive device 4. Matrix with adjustable printed stylus guide as described in section 3.
Print head. 5. Claim 1, characterized in that the air gap 37 between the magnet core 36 and the armature member 19 is adjustable by an adjustment bolt 40 attached to the casing 15 of the printing needle adjustment mechanism 3. A matrix print head having an adjustable printing stylus guide according to paragraph 4. 6. Claim 1, characterized in that the armature member 19 is disposed between the side guides 31.
A matrix print head equipped with an adjustable printing stylus guide according to any one of paragraphs 1 to 5.