JPS63312852A - Piezoelectric element drive type impact print head - Google Patents

Abstract

PURPOSE:To accurately transmit the elongation and contraction of a piezoelectric element without excess and deficiency by so disposing at lest one of two clamping means for clamping both first and second substrates at a frame as to cross the elongating or contracting direction of the element. CONSTITUTION:A printing unit 14 is inserted between partition walls 9 of a support 7 on a second substrate 3, and temporarily clamped by a clamping bolt 37 at a second substrate 3. Then, a first substrate 2 is turned over, and one end face of the frame 17 of a printing unit 14 is clamped by a clamping bolt 36 parallel to the elongating or contracting direction of a piezoelectric element 15 in a state in contact with the reference face F of the substrate 2. Thereafter, the bolt 37 of a direction crossing the elongating or contracting direction of the element 15 is clamped at an attachment piece 17a of the other end of the frame 17 to clamp both ends of the frame 17 of the unit 14. As a result, the attaching position of the frame 17 between the substrates 2 and 3 is not irregular in the elongating or contracting direction, and the elongation or contraction of the element 15 is accurately transmitted to a printing wire.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of application in the L industry) This invention relates to a piezoelectric element that expands and contracts when a voltage is applied, and a printing wire A that prints dots on a printing medium such as paper, and the expansion and contraction of the piezoelectric element. A motion transmission mechanism for transmitting motion to the element and motion transmission 41! The present invention relates to a piezoelectric element-driven VJ type impact print head in which a plurality of printing units constituted by a frame extending in the direction of expansion and contraction of the piezoelectric element are arrayed and supported on the frame.

(Prior Art) This type of print head includes, for example, Japanese Patent Application Laid-open IN+
There is one disclosed in Publication No. 60-969￥J.

In addition, in such a print head, recesses corresponding to the frames of the plurality of printing units 1 to 1 are formed in the head body, and the frames of the units 7 to 1 are respectively fitted into these recesses, and each presser foot There is one in which each printing unit is arranged and supported by holding down the frame. In the case of the J3 with this configuration, rattling may occur in the one-arrow portion between each of the four parts of the head body and the frame of each printing unit, which may adversely affect printing.

In order to fix each printing unit to the head body without any wobbling, the head body is made up of the first part. It is conceivable to fasten both ends of the frame of the character 11 unit to the second inner board using fastening means such as bolts.

(Problem to be solved by the invention) By the way, the piezoelectric element of the printing unit extends in the direction of expansion and contraction!
C1 in a frame supporting the piezoelectric element and supporting a motion transmission mechanism that transmits the expansion and contraction of the piezoelectric element to the printing wire. and the other end of the same frame to the second substrate, respectively, by tightening bolts parallel to the expansion and contraction direction of the piezoelectric element, the first
．． Between the second inner substrates, the position of each frame of the plurality of printing units is approximately one degree apart with respect to the direction of expansion and contraction of the piezoelectric element. Furthermore, each frame may be stretched in the direction of expansion and contraction of the piezoelectric element due to the tightening force of each of the bolts.

Furthermore, due to variation and elongation of the mounting positions of the respective frames in the direction of expansion and contraction of the piezoelectric element, there were problems such as the expansion and contraction of the piezoelectric element being unable to be transmitted to the printing Y V in an accurate manner. .

According to the present invention, the mounting position of the frame of each printing unit in the direction of expansion and contraction of the piezoelectric element is varied, and the frame is prevented from stretching, and both ends of the frame are connected to the first. Second
Among these, the technical problem to be solved is how to secure it to the substrate.

(Means for Solving the Problems) The present invention provides an L element that expands and contracts when a voltage is applied, and a method that transmits the expansion and contraction of the piezoelectric element to the printing wire A7 printed on the printing medium. A plurality of printing units each including a motion transmission mechanism, a frame supporting the element and the motion transmission structure and extending in the direction of expansion and contraction of the piezoelectric element, and supporting the frames of the printing unit 1- in an array. , draw a first substrate r3 that tightens one end of the frame in the expansion/contraction direction, and a second substrate that has a nose portion that supports the printing Y V and tightens the other end of the frame. , at least one of a fastening means for fastening the first board and the frame and a fastening means for fastening the second board and the frame is arranged to intersect with the expansion/contraction direction. The structure is sloppy.

(Function) According to the above configuration, both ends of the printing and TI unit frame are connected to the first. Among the fastening means r4 fastened to the second inner substrate, at least one of the fastening means is arranged so as to intersect the direction of expansion and contraction of the piezoelectric element. J3 between the second inner board
This prevents the mounting positions kj of the frames of each printing unit from varying in the direction of expansion and contraction of the piezoelectric element. In addition, the fastening force of the two fastening means prevents the room from being stretched in the direction of expansion and contraction of the piezoelectric element.

(Embodiment) An embodiment of the present invention will be described below with reference to the drawings.

In FIG. 1, which shows the print head from the side, and FIG. 2, which shows the print head from the front, the head main body 1 includes substantially rectangular plate-shaped first plates facing each other at a predetermined interval. It is mainly composed of second inner substrates 2 and 3 and pillars 4 that connect these inner substrates 2 and 3 at their four corners.

1st. Between the second IS plates 2 and 3, a plurality of (for example, 24) printing units 14 are arranged radially with respect to a center line passing through the center of these inner substrates 2.3.

On the front side of the second substrate 3, each printing 1 nit 1/I
A hollow nose portion 6 is provided in which a predetermined number of Iζ guide plates 5 for movably guiding the printing Y\730 are provided. Furthermore, the 20th λ is printed on the inner surface of the root 3: L
Support body 7 for radially positioning and supporting the unit 4
is arranged and there is C. This support body 7 is formed on a disc-shaped support plate 8 along the inner surface of the second substrate 3 and on the outer peripheral edge of this support plate 8, and is arranged radially between each adjacent printing unit 14. A frame 17 of the printing unit 14 is installed between each partition wall 9.
A support ring 10 is formed to support the outer surface of the holder. Furthermore, a center hole 11 that communicates with the inner hole of the nose portion 6 is provided in the center of the support plate 8, and a center hole 11 is provided on the inner surface of the 8Jl support plate 8 along the circumference of the center hole 11. A predetermined number of guide pins 12 for tilting and guiding the wire support arm 27 of each print-L unit 4 are provided in a protruding manner.

As shown in FIGS. 3, 4, and 5, each of the printing units 14 has a frame 17 equipped with a piezoelectric element 15 that expands and contracts when a voltage is applied, and a piezoelectric element 15 that expands and contracts when the piezoelectric element 15 prints. A motion transmission mechanism 16 for transmitting the motion to the wire V is disposed and supported.

The frame 17 is made of a metal plate having a vertically long rectangular shape substantially parallel to the expansion/contraction direction Ij of the piezoelectric element 15 and having a predetermined thickness. A piezoelectric element 15 is attached to the lower end of one side of the frame 17.
A support portion 19 that supports one end of the support member 19 through a temperature compensator 18 is provided to protrude in the lateral direction.

The piezoelectric ceramic layer 15 is made of laminated piezoelectric ceramic, and is expanded and contracted in the M layer direction (longitudinal direction) by applying a voltage. A temperature compensating material 18 is fixed to one end surface of the piezoelectric element 15 with an adhesive or the like. The pressure ff1i element 15 is supported on the support surface 19a of the support portion 19 in its temperature compensation material 18.

On the other end surface of the piezoelectric element 15, there is a rectangular iiJ motion equivalent 2.
It is fixed with adhesive material etc. This mover 20 is
The negative side faces the upper part of the negative side of the frame 17 with a predetermined gap. On the facing surfaces of the frame 17 and the mover 20, there are spring mounting surfaces 23, 24 for fixing the first and second leaf springs 21, 22 in a pair in the direction of expansion and contraction of the main body 15. They are formed parallel to each other and have flat surfaces.

The first leaf spring 21 is fixed to the spring mounting surface 23 of the frame 17 by brazing U or the like with one side of the first leaf spring 21 in contact with the spring.

A second leaf spring 22 is mounted on the spring mounting surface 24 of the movable element 20.
In the state in which the side plate surface is rotated (fixed by brazing etc.) It is polymerized to have the ability to move 0I.

Said 1st. Both second leaf springs 21 and 22 extend a predetermined length tJ from their respective spring mounting surfaces 23 and 24 in the direction of expansion and contraction of the piezoelectric element 15. A tilting member 25 is fixed to the tip end portions of both the first and second leaf springs 21,22. The tilting member 25 has a highly rigid base body 26 at its base, and
Main body is C
It is configured.

The base body 26 has a groove 28 recessed in its lower surface.
．． In the inserted state, the tips of the second leaf springs 21 and 22 are fixed to opposite sides of the opposite surfaces of the leaf springs 21 and 22 by brazing. The base of the wire support arm 27 is inserted into a groove 29 formed in the front side of the base body 26 and fixed thereto with a wax. The base end of a printing wire 30 is fixed to the tip of the wire support arm 27 by brazing.

Further, in this embodiment, in order to avoid moving the movable element 20 parallel to the direction of expansion and contraction of the Fi electric element 15 due to the application of voltage, an elastically deformable connecting tAt material 31 is provided between the frame 17 and the movable element 20. is installed. This connecting member 31 is longitudinally elongated along the stacking direction of the piezoelectric elements 15 on the side opposite to the frame 17, and its lower end is fixed to the end surface of the support part 19 of the frame 17, and its upper end is the third part of the 11T mover 20. It is fixed to the end face on the opposite side to the leaf spring 22 of No. 2.

Roughly speaking, the connecting member 31 is made of a plate material that has a plate width in a plane parallel to the plate surface of the frame 17 and is thin in a direction perpendicular thereto. The elastic force of the connecting member 31 is set so that the moving force of the movable element 20 due to the expansion of the piezoelectric element 15 acts almost equally on the second plate spring 22 and the connecting part 4131. 20 is F
[It is adapted to be moved in parallel in the direction of expansion and contraction of the mold element 15.]

Further, in this embodiment, at one end of the connecting member 31,
A pax 1-flange 32 made of low-resilience rubber is provided for abutting and supporting one side of the wide-V support arm 27 when the tilting member 25 returns to its tilting position. This back stopper 32 has an adhesive groove 33 for connecting member 31.
is formed.

Then, the back stopper 32 is fitted into the upper end of the connecting member 31 in its adhesive groove 33, and the adhesive tlli 33 is filled with adhesive from the adhesive filling holes 34 arranged in 11 stages on one side of the back stopper 32. By doing so, the back stopper 32 is fixed to the connecting member 31.

Note that the temperature compensating material 18 bonded to the lower end surface of the If electric element 15 is
) by the expansion (corrected, the support G of the frame 17
From the support surface 19a of the j section 19 to the end of the piezoelectric cord 15
The height of C is kept constant.

In addition, by slightly pushing up the lower surface of the temperature compensator 1a on the support part 19a, the connecting member 31 and the second leaf spring 22 A push pin 35 is provided for applying a spring force to the piezoelectric element 15 and constantly applying a compressive force to the piezoelectric cord 15.
After being driven in, the push-up pin 35 is fixed integrally with the support portion 19 by beam welding.

Each of the lead wires 38 and 39 led out with one end connected to both electrodes of the piezoelectric cord 15 of each printing unit 14 is supported by a holder 40 made of an electrically insulating material, and each other end is connected to the first substrate. It is connected by soldering to a predetermined power supply line 51 which is disposed and supported on a wiring board 5 made of electrically insulating T4 material and which is fixed to the outer surface of the board 2.

Each of the holders 40 includes a cylindrical support portion 41 that fits around the outer periphery of each indenter 15, and a wiring board that passes through a through hole 2a formed in the first substrate 2 from one side of the support portion 41. 50
The main body is a leg portion 42 that extends to the inner surface of the holder. A lead wire 38 led out from both electrodes of each pressure element 15 is attached to one side of the leg portion 42 of each holder 40.
Two guide grooves 43 and 44 are recessed for guiding and supporting the wiring board 39 toward the wiring board 50. Furthermore, the wiring board 50
A guide piece 4 is attached to one side of the end of the leg 42 that is in contact with the inner side of the leg 42.
5 is provided protrudingly, and each guide groove 43 is provided on this guide piece 45.
．． 44 is provided with through holes 46 and 47 through which the continuous FA is inserted.

The lead wires 38, 39 guided in the respective guide grooves 43, 44 are passed through the respective through holes 46, 47, and each end thereof is formed in a through hole (not shown) formed in the wiring board 50. and is connected to a predetermined power supply line 51 by soldering.

Note that a signal based on print data is sent to the power supply 1i151 of the wiring board 50 from the control circuit.

Now, each printing unit 4 configured as described above prints the inner surface of the first glue plate 2 as
With one end surface of the frame 17 of the button 14 in contact with each printed image on this reference surface F, the first substrate 2
The frame 17 is fastened by screwing a tightening bolt 36 parallel to the direction of expansion and contraction of the first electric element 15 into one end of the frame 17 from the outer surface of the frame 17 .

In the second substrate 3 whose other end side is fastened to the frame 17 by a tightening bolt 37, each printing unit 14 is provided on the inner surface of the plate-shaped portion 3a along the direction in which the printing units 14 are arranged. Tightening pieces 13 for tightening the frame 17 (f) are each protruded at right angles. Each of these tightening pieces 13
A long attachment hole 13a is formed in the direction of expansion and contraction of the piezoelectric cord 15. Then, tighten the tightening bolt 37 in the direction crossing the direction of expansion and contraction of the piezoelectric cord 15 into the mounting hole 1 of the tightening piece 13.
3a, each frame 1 of the printing unit 14.
The other end of each frame 17 is fastened to the second base 1f1i3 by screwing into a mounting piece 17a protruding from the other end surface of the frame 7.

In addition, in this embodiment, the pillar 4 of the head body 1, the printing
The frame 17 and the connecting member 31 of the L-knit 14 are made of materials with the same linear swelling ratio, so that they can cope with temperature changes.

This embodiment is constructed as described above. therefore,
A signal based on the printing data is output from the control circuit to each printing unit 14, and an electric current j1 is generated between both electrodes of the piezoelectric element 15.
When is applied, the piezoelectric element 15 extends by a predetermined length in the stacking direction, that is, in the direction of arrow X in FIG.
Along with this, the mover 20 is moved. Then, the second leaf spring 22 is pushed up along the first leaf spring 21 by the moving force of the movable element 20, and the second leaf spring 22 is moved between the movable element 20 and the base body 26 of the tilting member 25. It is elastically deformed into a curved shape between. Due to the curved elastic deformation of the second leaf spring 22, a rotational moment is generated in the direction of arrow P in FIG. Ru. Then, the printing wire S730 at the tip of the tilting member 25 is guided by a predetermined number of guide plates 5, and its tip is advanced to the printing position. In this way, by tilting the tilting member 25 due to the curved elastic deformation of the second leaf spring 22, the elongation of the piezoelectric element 15 is smoothly expanded (printing width \/
30.

When the voltage is no longer applied to the piezoelectric element 15, the piezoelectric element 15 is shortened to its original state. Then, the mover 20,
1st. The second leaf springs 21, 22 and the tilting member 25 are returned to their original states, and the printing wire 30 is returned to its original position.

Now, after the printing unit 14 is inserted between the partition walls 9 of the support 14 body 7 on the second board 3 and temporarily attached to the second board 3 with the bolts 37, the printing unit 14 is inserted into the first 24 boards. 2 is covered and one end surface of the frame 17 of the printing unit 14 is in contact with the reference surface F of the first substrate 2.
Tighten l by bolt 36 parallel to the expansion and contraction direction of 5.
l1i@ will be done. Then, by tightening the tightening bolt 37 in the direction that intersects the direction of expansion and contraction of the electric terminal 15 to the mounting piece 17a at the other end of the frame 17, both ends of the frame 17 of each printing unit 14 are tightened. It will be worn. Therefore, the frame 17 of each printing unit 14 is uneven in the direction of expansion and contraction of the piezoelectric element 15, and the first. The problem of being stuck between the second substrates 2 and 3 is eliminated.

Roughly speaking, since the tightening force of each tightening bolt 36, 37 that tightens both ends of the frame 17 does not act to extend the frame 17 in the direction of extension and contraction of the electric cable 14,
The elongation of the frame 17 is also eliminated.

In the above embodiment, a tightening piece is provided on the inner surface of the first substrate 2 to protrude at right angles, and the tightening bolt 36 inserted into the tightening piece is used to tighten the frame from a direction perpendicular to the direction of expansion and contraction of the piezoelectric element. 17 may be tightened.

(Effects of the Invention) As described above, according to the present invention, the first. In a device in which both ends of the frame of the printing unit are fastened to the second substrate by fastening means such as bolts, at least one of the fastening means is connected in the direction of expansion and contraction of the piezoelectric element. By arranging them so that they intersect, the first. Second
By attaching the frame of each printing unit between the two special plates, it is possible to prevent the position from varying in the direction of expansion and contraction of the piezoelectric element. Further, it is possible to prevent the frame from being stretched in the direction of expansion and contraction of the J-type cord due to the mutual binding force of the two fastening Ts. As a result,
There is an effect that the expansion and contraction of the piezoelectric element can be accurately transmitted to the printing liar 1 through the motion transmission mechanism.

[Brief explanation of drawings]

The drawings show one embodiment of the present invention; FIG. 1 is a side sectional view of the print head, FIG. 2 is a front view of the print head with parts broken, and FIG. 3 is a diagram showing the arrangement of the print head. FIG. 4 is a side view of the printing unit, and FIG. 5 is a plan view of the printing unit. 1... Head main body 2... First substrate 3... Second glue plate 4... Pillar (column member) 6... Nose portion 14... Printing unit 15... Piezoelectric element 16 ... Luck fJJ transmission mechanism 17... Frame 20... Mover! 21...First leaf spring 22...Second leaf spring 25...Tilt member 36.37...Tighten (' = J bolt (fastening means) Applicant Brazi Industries Co., Ltd. Agent Valve Fl! i-Hidehiko Okada (2 others) 17, a Figure 3

Claims (3)

[Claims] (1) A piezoelectric element that expands and contracts when a voltage is applied, a motion transmission mechanism that transmits the expansion and contraction of the piezoelectric element to a printing wire printed on a printing medium, and a piezoelectric element that supports the element and the motion transmission mechanism, and a plurality of printing units each including a frame extending in the expansion/contraction direction of the element; a first substrate that supports the frames of the printing unit in an array and fastens one end of the frame in the expansion/contraction direction; and the printing unit. a second board that has a nose portion that supports a wire and that fastens the other end of the frame; fastening means that fastens the first board and the frame; and the second board A piezoelectric element-driven impact print head, characterized in that at least one of the fastening means for fastening the frame and the frame is disposed so as to intersect with the expansion/contraction direction. (2) The piezoelectric element-driven impact printing according to claim 1, wherein the first substrate and the second substrate are connected by a plurality of pillar members extending parallel to the frame. head. (3) the second substrate includes a plate-shaped portion along the arrangement direction of the printing units and a portion protruding in the expansion/contraction direction;
The piezoelectric element-driven impact print head according to claim 1, wherein the other end of the frame is fastened by fastening means inserted into the protruding portion from a direction substantially perpendicular to the direction of expansion and contraction.