JPH0443517B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a printing hammer mechanism, and more particularly to a printing hammer mechanism for a dot impact printer that prints characters or figures in the form of a dot matrix.

[Conventional technology]

The printing hammer mechanism of conventional dot impact printers uses many electromagnets and permanent magnets, and when desired, electric power is applied from outside to excite the electromagnets and generate enough magnetic flux to cancel the magnetic flux of the permanent magnets. The print hammer was driven by the generated print hammer.

[Problems to be solved]

However, since electromagnets are used in the printing hammer mechanism of conventional dot impact printers, the input energy is large due to the joule heat generated by the electromagnetic coils, the eddy currents and hysteresis losses generated by the yoke and armature, etc. The disadvantage was that some parts of the system became heat and dissipated, resulting in extremely poor energy efficiency. Therefore, a large drive circuit is required, and the power supply capacity also becomes large, resulting in an increase in manufacturing costs. In addition, a large amount of iron and copper must be used, resulting in a large weight, which has the drawback of hindering printers from being faster, smaller, lighter, and less expensive.

[Means for solving problems]

In order to solve the above-mentioned drawbacks of the printing hammer mechanism of the conventional dot impact printer, the present invention has the following features:
It is an object of the present invention to provide a new printing hammer mechanism for a dot impact printer that can improve energy efficiency, reduce manufacturing costs, and reduce weight by eliminating electromagnets and permanent magnets.

For this purpose, the present invention includes a piezo element, a frame having one end of the piezo element fixed to a base part, and a frame having one end fixed to the other end of the piezo element and an intermediate part connected to the base part of the frame via a rotation fulcrum. a U-shaped outer frame having a central portion fixed to the other end of the lever arm, and one end of a printing wire fixed to an upper end portion fixed to both ends of the U-shaped outer frame. a printing hammer, one end of which is connected to the portion to which both ends of the U-shaped outer frame are fixed, the other end of which is locked to the base of the frame, and the center portion of which is connected in the direction in which the other end of the printing wire extends. and a buckling spring that is protruded and curved in a direction opposite to that of the lever arm and that snaps in response to the swinging of the other end of the lever arm in response to expansion and contraction of the piezo element. It provides:

〔Example〕

Next, the present invention will be explained in detail with reference to the drawings.

FIG. 1 is a perspective view of an embodiment of the printing hammer mechanism of the present invention.

Reference numeral 1 denotes a frame having a rigid body that can be considered as a rigid body, and is formed such that both leg portions 1b and 1c are parallel to a base portion 1a, and an extension portion 1d is formed at the end of one leg portion 1b. ing. 2
is a piezo element disposed between both ends 1b and 1c of the frame 1, and one end is fixed to the base part 1a of the frame 1. Reference numeral 3 denotes a lever arm whose one end, that is, the input end 3a, is fixed to the other end of the piezo element 2, and whose intermediate part 3b is fixed to the end of the leg part 1c of the frame 1 via the hinge part 4. The piezo element 2 swings with the hinge portion 4 as a rotational fulcrum in response to the expansion and contraction operations of the piezo element 2. Reference numeral 5 denotes a printing hammer whose upper or free end is fixed to one end of the printing wire 6 extending in the direction in which the piezo element 2 is arranged, and whose lower or fixed end is attached to the tip of the extension 1d of the frame 1. It is locked,
The center portion is a buckling spring 7 which is curved and protrudes in a direction opposite to the direction in which the printing wire 6 extends. 8
is a U that functions as a substantially rigid body whose central portion is fixed to the other end of the lever arm 3, that is, the output end 3c.
It is a character-shaped outer frame, and both ends 8a and 8b are fixed near the connecting part between the upper end of the printing hammer 5 and the buckling spring 7.

Further, the operation of the printing hammer mechanism of the present invention shown in FIG. 1 will be explained.

When a voltage is applied to the piezo element 2, the piezo element 2 rapidly contracts in the direction of arrow A due to electrostatic polarization. As the piezo element 2 contracts, the input end 3a of the lever arm 3 is pulled in the direction of arrow A, so the lever arm 3 rotates around the hinge part 4, and the output end 3c expands the contraction operation of the piezo element 2. and rapidly move in the direction of arrow B. As the output end 3c of the lever arm 3 moves in the direction of arrow B, the center portion of the U-shaped outer frame 8 is also moved in the direction of arrow B. When the central portion of the U-shaped outer frame 8 moves to some extent in the direction of arrow B, a snapping action occurs due to the action of the buckling spring 7, and the printing wire 6 of the printing hammer 5 suddenly and largely jumps out in the direction of arrow C. As a result, the printing wire 6 performs a predetermined printing operation.

When the voltage applied to the piezo element 2 is removed,
The piezo element 2 rapidly expands in the direction opposite to the direction of arrow A and returns to its initial state. As the piezo element 2 expands, the input end 3a of the lever arm 3 is pressed in the direction opposite to the direction of arrow A, so the lever arm 3 rotates around the hinge part 4 and the output end 3c moves in the direction of arrow B. moves rapidly in the opposite direction. As the output end 3c of the lever arm 3 moves in the direction opposite to the direction of arrow B, the center portion of the U-shaped outer frame 8 is also moved in the direction opposite to the direction of arrow B. When the center part of the U-shaped outer frame 8 moves to some extent in the direction opposite to the direction of arrow B, a snapping action occurs due to the action of the buckling spring 7, and the printing wire 6 of the printing hammer 5 is suddenly and largely displaced, and is moved in the direction of arrow C. retreat in the opposite direction.
As a result, the printing wire 6 returns to its original state and completes the predetermined printing operation.

FIG. 2 is a perspective view of another embodiment of the printing hammer mechanism of the present invention.

Reference numeral 11 denotes a frame having a rigid body that can be considered as a rigid body.
11c are formed to be parallel to each other, and an extension portion 11d is formed at the end of one leg portion 11b. A piezo element 12 is disposed between the legs 11b and 11c of the frame 11, and one end thereof is fixed to the base 11a of the frame 11. A lever arm 13 has one end, that is, an input end 13a, fixed to the other end of the piezo element 12, and an intermediate part 13b is fixed to the ends of the frame 11 and the leg part 11c via a hinge part 14. The piezo element 12 swings with the hinge portion 14 serving as a rotational fulcrum in response to the expansion and contraction operations of the piezo element 12. 15
is a printing hammer whose upper or free end is fixed to one end of the printing wire 16 extending in the opposite direction to the direction in which the piezo elements 12 are disposed, and whose lower or fixed end is attached to the extension 11d of the frame 11.
The buckling spring 17 is fixed to the tip end of the printing wire 16, and the center portion thereof is bent in a direction opposite to the direction in which the printing wire 16 extends. 18, the center portion is the other end of the lever arm 13, that is, the output end 13c.
It is a U-shaped outer frame that functions as a substantially rigid body, and both ends 18a and 18b are attached to the printing hammer 15.
The upper end portion of the buckling spring 17 is fixed near the connecting portion between the buckling spring 17 and the buckling spring 17.

Furthermore, the operation of the printing hammer mechanism of the present invention shown in FIG. 2 will be explained.

When a voltage is applied to the piezo element 12, the piezo element 12 rapidly expands in the direction of the lost mark A. As the piezo element 12 extends, the input end 13a of the lever arm 13 is pressed in the direction of arrow A, so the lever arm 13 rotates around the hinge part 14, and the output end 13c controls the elongation of the piezo element 12. It enlarges and moves rapidly in the direction of arrow B. Lever arm 1
As the 3a output end 13c moves in the direction of arrow B, the center portion of the U-shaped outer frame 18 is also moved in the direction of arrow B. When the center of the U-shaped outer frame 18 moves to a certain extent in the direction of arrow B, a snap action occurs due to the action of the buckling spring 17, and the printing wire 16 of the printing hammer 15
jumps out in the direction of arrow C with a sudden and large displacement.
As a result, the printing wire 16 performs a predetermined printing operation.

When the voltage applied to the piezo element 12 is removed, the piezo element rapidly contracts in the direction opposite to the direction of arrow A and returns to its original state. Viezo element 1
2, the input end 1 of the lever arm 13
3a is pulled in the direction opposite to the direction of arrow A, the lever arm 13 rotates around the hinge portion 14, and the output end 13c rapidly moves in the direction opposite to the direction of arrow B. Output end 13c of lever arm 13
As U moves in the direction opposite to the direction of arrow B,
The center portion of the character-shaped outer frame 18 is also moved in the direction opposite to the direction of arrow B. The center part of the U-shaped outer frame 18 is indicated by arrow B.
When the printing wire 16 moves to a certain extent in the opposite direction, a snapping action occurs due to the action of the buckling spring 17, and the printing wire 16 of the printing hammer 15 is rapidly and largely displaced, retreating in the direction opposite to the direction of the arrow C. As a result, the printing wire 16 returns to its original state and completes the predetermined printing operation.

〔Effect of the invention〕

As is clear from the above, the present invention utilizes the deformation of the piezo element due to electrostatic polarization, and uses a displacement magnification mechanism using a lever mechanism provided on the frame and a snap action mechanism using a buckling spring to expand the displacement of the piezo element. By expanding the amount of minute deformation and using this expanded displacement output to operate the printing hammer integrated with the snap operation mechanism, it generates less heat than the conventional electromagnetic printing hammer mechanism, making it extremely energy efficient. This has the effect of providing a high-speed printing hammer mechanism. Further, since the present invention utilizes a two-stage amplification displacement magnification mechanism using a lever mechanism and a snap operation mechanism, it is possible to easily obtain a large magnification ratio and, as a result, it has the effect of being able to be miniaturized.
In addition, in the present invention, since the printing hammer is driven by a snap action, it has the effect of making it possible to achieve a fixed printing operation and speeding up the printing operation. Further, since the present invention only utilizes a piezo element lever mechanism and a snap operation mechanism, it has the effect of reducing manufacturing costs.

[Brief explanation of drawings]

1 and 2 are perspective views of embodiments of the printing hammer mechanism of the present invention, respectively. 1, 11... Frame, 2, 12... Piezo element, 3, 13... Reper arm, 4, 14... Hinge section, 5, 15... Printing hammer, 6, 16...
Printing wire, 7, 17...Buckling spring, 8, 18...
...U-shaped outer frame.

Claims (1)

[Claims] 1 A piezo element, a frame having one end of the piezo element fixed to a base part, and a lever having one end fixed to the other end of the piezo element and an intermediate part fixed to the base part of the frame via a rotation fulcrum. an arm, a U-shaped outer frame having a center portion fixed to the other end of the lever arm, and a printing hammer having one end of a printing wire fixed to an upper end portion fixed to both ends of the U-shaped outer frame; One end is connected to the portion to which both ends of the U-shaped outer frame are fixed, the other end is locked to the base portion of the frame, and the central portion extends in a direction opposite to the extending direction of the other end of the printing wire. 1. A printing hammer mechanism comprising: a buckling spring that is protrudingly curved and snaps in response to swinging of the other end of the lever arm in response to expansion and contraction of the piezo element.