JPS61217262A - Printing hammer - Google Patents

Abstract

PURPOSE:To provide a fast-operating, highly reliable printing hammer by actuating more than two pieces of piezoelectric elements and flying members alternately to put a printing member in action. CONSTITUTION:A piezoelectric element serving as a driving source is composed of the first and second piezoelectric elements 8a, 8b. Each piezoelectric element has a power transmission on the front to provide power to a flying member, and the first and second flying members 4a, 4b are arranged on the front of each power transmission member 9 so that it may be pressed by a return spring. The first and second flying members 4a, 4b are caused to operate alternately making one set of two pieces so that a printing member 1 may be operated. In addition, the printing member 1 is subjected to the restriction of its return action after printing by a stopper 7 provided at the rear. Thus the rebound action effect is minimized by operating more than two pieces of piezoelectric elements and flying members alternately and the following operation can be accelerated. Consequently, it is possible to obtain a printing hammer capable of fast printing.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an impact-type printing hammer, and particularly to a free-flight printing hammer.

(Prior art and its problems) A free-flying printing hammer has the advantage of being able to provide a long stroke.

Conventionally, free-flying printing hammers using electromagnets have been widely used. However, those using electromagnets have low electrical/mechanical energy conversion efficiency, so it is necessary to provide a large amount of input energy for the required printing energy, and the use of electromagnets increases the size.

Therefore, in recent years, a printing hammer using a piezoelectric element with high electrical/mechanical energy conversion efficiency as a driving source has been considered. For example, Japanese Patent Publication No. 59-45165 discloses a printing hammer as shown in FIG. In FIG. M6, the piezoelectric element 61 has one end connected to the attachment member 62 and the other end connected to the force transmission member 63. In addition, the printing wire 6
The mooring portion 65 to which 4 is connected is pressed against the force transmitting member 63 by a coil spring 66. A printing wire 64 is supported by a guide hole 67.

When a voltage is applied to the piezoelectric element 61 during printing, the piezoelectric element 6
1 extends at high speed in the direction of arrow A, and the force transmitting member 63 is also displaced. Therefore, the printing wire 64 and the mooring portion 65 are accelerated by the force transmitted by the force transmitting member 63, fly freely over a much longer distance than the amount of extension of the piezoelectric element 61, and print dots at the tip of the printing wire 64.

A free-flying printing hammer using such a piezoelectric element has a simple structure and can be miniaturized. However, the method of free flight by applying force to the mooring part 65 by high-speed operation of the piezoelectric element conversely causes the printing wire 64 and the mooring part 65 to collide with the force transmission member 63 when they return to their original positions after printing. Rebound occurs, and the next printing operation or flight operation becomes difficult until the rebound operation subsides. In other words, in order to allow the printing wire 64 and the mooring portion 65 to fly freely, the force transmission member 63 and the mooring portion 65 must be hard enough to transmit force, and if the material is soft, the piezoelectric element 61 The movement is absorbed, making it difficult to fly freely. On the other hand, when the mooring portion 65 returns to its original position after printing, that is, when it comes into contact with the force transmitting member 63, a hard material causes rebound due to the repulsion. Although the piezoelectric element 61 operates at high speed, the amount of displacement is small, so if the amount of rebound is large, the next flight operation will be difficult. Printing hammers are required to have a simple and compact structure, and are also required to have a high printing speed, and the long waiting time for the rebound to settle down is a problem in increasing the speed.

(Object of the Invention) The object of the present invention is to eliminate the drawbacks of the conventional printing presses, and to provide a printing machine that is capable of high-speed operation and has high reliability.

(Structure of the Invention) According to the present invention, in a printing hammer that performs a printing operation by causing a printing needle to fly freely by the expansion and contraction movement of an electrostrictive or piezoelectric element, there is provided a printing member whose return movement is restricted by a stopper, and the printing member. at least two or more flying members disposed behind the board with a gap therebetween for applying force to the printing member; and 1. corresponding to the rear of each flying member. give force λ
, and the flying member is pressed against the electrostrictive or piezoelectric element by a return spring.

(Details of the configuration will be explained) The present invention solves the problems of the prior art by adopting the above-mentioned configuration.

First, the electrostrictive or piezoelectric element serving as the driving source is composed of at least two elements. One piezoelectric element is provided with a first piezoelectric element, and a second piezoelectric element is provided in parallel with the first piezoelectric element. At this time, the first and second piezoelectric elements extend and contract in the same direction, but each piezoelectric element is configured so that it can operate independently without interfering with each other's operations. That is, the piezoelectric element from which the drive source is driven is constituted by the second piezoelectric element.

Further, each piezoelectric element is provided with a force transmission device on its front surface to apply a force to the flight member, and the first and second flight members are arranged on the front surface of each force transmission member so as to be pressed by a return spring. Ru. Furthermore, a printing member serving as a printing means is arranged via a gap between the first and second flying members,
The printing member receives force from the first and second flying members. That is, the first and second flight members are 2.
A force is applied to the printing member as a set. Further, the printing member is restricted from returning after printing by a stopper at the rear. When a voltage is applied to the piezoelectric element in the metal part, the electrostrictive or piezoelectric element displaces very quickly, although slightly, so the first flying member It is accelerated by the force, leaves the force transmission member, and flies.

The rear flying member collides with the printing member, and the printing member moves forward due to the force and hits the paper and ink ribbon on the platen to perform a printing operation.

At the start of the printing operation, the first piezoelectric element only needs to be excited for a period of time to allow the first flying member to fly freely, and the applied voltage may be stopped when the flying member leaves the force transmitting member. . Further, after such a printing operation, the flying member returns to its original state due to the force of the return spring and the repulsive force of the printing member, but at this time, the flying member collides with the force transmitting member and rebounds. - On the other hand, the printing member also returns to its original position, but is braked by a stopper with a buffering effect. Here, the first flying member is rebounding on the force transmission member on the first piezoelectric element, and then a voltage is applied to the second piezoelectric element to cause the second flying member to fly. At this time, the printing member also rebounds to some extent on the stopper, but since the flight distance of the second flying member is large, the printing member can be easily moved by the collision action. Also, after printing, the second flying member collides with the force transmission member on the second piezoelectric element due to return, causing a rebound, but at this time, the above-mentioned first flying member HQ bounding action causes a force There is. Therefore, the next operation is performed by the first piezoelectric element.

By alternately operating two or more piezoelectric elements and the flying member in this way, it is possible to reduce the influence of the rebound operation and hasten the next operation of the printing member, making it possible to obtain a printing hammer capable of high-speed printing. can.

(Example) Examples of the present invention will be described in detail below with reference to the drawings.

FIG. 1 is a diagram showing one embodiment of the present invention, and FIG. 2 is a diagram for explaining the usage pattern of the embodiment of FIG. 1. In FIG. 1, a plate 2 with a printing needle 1 provided at its free end
is fixed to the attachment member 3 to constitute a printing member. Further, first and second flying members 4a and 4b are provided on the back surface of the plate genera 2 with a gap therebetween, and the first and second flying members 4a,
4b is supported by the guide hole 5 and is provided with a return barb 6. Also, on the back side of the leaf spring 2, there is a leaf spring 2.
A stopper is provided which dampens the return movement of the cylinder by a buffering effect. Furthermore, first and second flight members 4a, 4b
and the first and second flight members 4a, 4b corresponding to
The first and second piezoelectric elements 8a extend and contract in the direction of
, 8b are arranged and connected to the reporting member 3. First of all,
The first and twelfth piezoelectric elements 8a and 8b are separated from each other so that they can operate independently of each other, or the space between them is filled with a soft insulating material such as silicone rubber. A force transmitting member 9 made of a hard material such as metal is provided on the front surface of the first and second piezoelectric elements 8a and 8b, and a first and second flying member 4a are provided on the front surface of the force transmitting member 9, respectively.

4b is pressed and in contact with the return barb 6.

In such a structure, when a voltage is first applied to the first piezoelectric element 8a, the first piezoelectric element 8a as shown in FIG. 2(a)
A is displaced at high speed in the direction of arrow A, receives a force from the force transmission member 9 of the first flight member 4ald, and flies freely.

The rear flight member 4a collides with the front leaf spring 2,
The plate spring 2 is moved forward by the force, and hits the printing needle 1j on the plate spring 2, the platen 10, the printing paper 11, and the ink ribbon 12 to perform a printing operation. At this time, as shown in Figure 2 (
As shown in c), the first flying member 4a and the printing needle 1 move at a distance 14.1 which is much longer than the displacement 13 of the first piezoelectric element 8a.
Can move 5. Further, since the first flying member 4ai is caused to fly when the first piezoelectric element 8aFi reaches its maximum speed by its displacement operation, the applied voltage may be stopped when the first flying member 4a flies freely, and the first piezoelectric element 83 returns to its original length. The constant-temperature flying member 4a returns to its original position due to the repulsive force caused by the impact with the leaf spring 2 and the return spring 6, although the return speed varies depending on its mass. At this time, rebound occurs due to the impact with the force transmission member 9.

However, since the leaf spring 2 and the first flying member 4a are arranged apart from each other, the rebound of the first flying member 4a does not have any influence on the leaf spring 2. Further, the plate genera 2 is returned to its original position by the eye panel after the printing operation, but is braked by the stopper 7 which has a buffering effect. In addition, in the case of the next printing operation, the first flying member 4a still performs the rebound operation, but this time, as shown in FIGS. 2(b) and 2(c).
A voltage K is applied to the second piezoelectric element 8b as shown in FIG. 2, and the second flying member 4b is caused to fly freely by displacement 16 in the B direction.

Therefore, the leaf spring 24 is operated by the second flight member 4b. The leaf spring 2 also makes a slight rebound movement on the stopper 7, but since the flying distance 17 of the second flying member 4b is large, the leaf spring 2 is easily moved forward as shown in FIG. The printing operation can be performed by moving to □.In the next operation after the bending, the rebound of the first flying member 4a is exhausted, so the first piezoelectric element 88 is applied next. to operate the first flying member 4a to print.In this way, the first and second piezoelectric elements 8a, 8b and the flying member 4
By operating a and 4b, the leaf spring 2, which is a printing member, can be moved, and a delay in printing operation due to rebound can be prevented. As a result, a printing hammer for a printer capable of high-speed printing is obtained. Figure 2 (dl) is a conventional example in which the present invention is used, and the flying member is combined with the printing needle or serves as the printing needle, but since the flying member is allowed to fly freely, it has good force transmission efficiency. If only a hard force transmission member is used, the flight conditions are good, but on the other hand, when returning, the flight member collides with the force transmission member, resulting in a large rebound movement18.The amount of rebound is approximately half that of free flight. In some cases, it takes a long time for this rebound to be braked.The present invention eliminates these problems, provides a hammer that can be braked in a short time, and can perform high-speed printing operations.

In a printer, a line printer can be obtained by arranging such hammers horizontally, and a serial printer can be obtained by arranging them in a cylindrical shape. According to the present invention, it is possible to obtain a printing hammer for a printer that can be driven with low power, is compact, has a simple structure, and has a high speed.

FIG. 3 is a diagram showing another embodiment of the present invention.

In FIG. 3, the driving sources are the first, second,
Third piezoelectric elements 8a, 8b, 8e and corresponding first, second and third flight members 4a, 4b.

A leaf spring 2 having a printing needle 1 is operated by alternately operating 4ci. If the number of driving sources is increased in this way, the flight member 4
Even if the rebound operations of a, 4b, and 4c take a long time, the printing operation can be performed using other flying members, so that a printing hammer capable of high-speed printing operation can be obtained.

FIG. 4 is a diagram showing another embodiment of the present invention, in which the present invention is applied to a printing hem for a serial printer using a wire. In FIG. 4, the printing wire 19 is connected to the guide hole 20.
and behind it are the first and second flight section sides 4a.
, 4b, and first and second piezoelectric elements 8a serving as driving sources,
8b is placed. In this embodiment as well, a high-speed printing hammer can be obtained by alternately operating the first and second piezoelectric elements 8a and 8b.

FIG. 5 is a diagram showing another embodiment of the present invention, in which the first and second flying members 4a and 4b, which fly by the first and second piezoelectric elements 8a and 8b, are moved by a return leaf spring 21. I support it. Such a return leaf spring 21#'i stabilizes the flying motion of the first and second flying members 4a and 4b, and a printing hammer that does not require guide holes can be obtained. It goes without saying that even in this configuration, the plate springs 2, which have the entire printing needle 1, can operate at high speed, and a high-speed printing hammer can be obtained.

In the present invention described above, the piezoelectric element serving as the driving source can be applied in the case of a single plate with vertical effect or horizontal effect, or in the case of laminating multiple pieces, or even an electrostrictive element. Effects can be obtained.

(Effects of the Invention) According to the present invention, by having at least two or more piezoelectric elements and flying members and operating them alternately to operate the printing member, printing operation can be accelerated and high-speed printing operation can be performed.
You can get a small size and simple structure for printing.

[Brief explanation of drawings]

FIG. 1 is a diagram showing one embodiment of the present invention, FIG. 2 is a diagram for explaining the usage form of FIG. 1, FIG. 3 is a diagram showing another embodiment of the present invention, and FIG. Diagrams showing other embodiments of the present invention,
FIG. 5 is a diagram showing another embodiment of the present invention, and FIG. 6 is a diagram showing a conventional embodiment. Each symbol in the figure indicates the following content. DESCRIPTION OF SYMBOLS 1... Printing needle, 2... Plate spring, 3. 62... Attachment member, 4a... First flight member, 4b... Second flight member, 4c... Third flight member. Third flight member, 5,20.67・
... Guide hole, 6... Return spring, 7... Stopper, 8a... First piezoelectric element, 8b... Second piezoelectric element, 8c... Third piezoelectric element, 9. 63... Force transmission member, 10... Platen, 11... Printing paper, 12
... Ink ribbon, 13... Displacement of first piezoelectric element, 14... Displacement of first flight member, 15... Displacement of printing needle, 16... Displacement of second piezoelectric element , 17...
Displacement of second flight member, 18... Displacement of flight member, 1
9.64...Printing wire, 21...Returning board Genese Patent Attorney Susumu Hara 0 Clause 1 Figure 1 (lily) ni J
Remuscle 5
Fig. 4b) Ninojo 2 Icho also F Honsai Fig. 6 67 Kai'id JL

Claims (1)

[Claims] In a printing hammer that performs a printing operation by causing a printing needle to fly freely through the expansion and contraction movement of an electrostrictive or piezoelectric element, there is a printing member whose return movement is restricted by a stopper, and a printing member which is arranged behind the printing member with a gap therebetween and is used for printing. It is composed of at least two or more flight members for applying force to the members, and an electrostrictive or piezoelectric element for applying force corresponding to the rear part of each of the flight members, and the flight member is operated by a return spring to A printing hammer characterized by being pressed against an electrostrictive or piezoelectric element.