JPS61168275A - Latch type piezoelectric actuator - Google Patents

Abstract

PURPOSE:To eliminate a magnetic interference with a simple structure, small- size, low power and low heating by applying a drive force to an inverting spring mechanism by a piezoelectric element. CONSTITUTION:A movable contact 3 is accelerated as a flying member by the forces generated at the first or second piezoelectric elements 5, 7 at voltage applying time, flown and a movable member is inverted. Thus, the stroke of the contact 3 of the magnitude of the times of several tens to several hundreds of the displacements of the elements 5, 7 can be obtained, and large contacting force is obtained. Further, since the piezoelectric element known as having high energy conversion efficiency is used as the drive source of the contact 3 as the member, magnetic interference is eliminated at low heating.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a latch-type actuator using a piezoelectric element.

(Prior art and its problems) Conventionally, electromagnetic actuators using coils have been used as latch-type actuators. However, electromagnetic actuators generate a magnetic field by energizing the coil and utilize the magnetic force. In order to move the movable members, a large amount of input energy is required, resulting in problems such as heat generation and magnetic interference.

Also, since it uses a coil, it was difficult to miniaturize it.

(Object of the invention) An object of the present invention is to eliminate such conventional drawbacks and provide a latch-type piezoelectric actuator with a simple structure, small size, low power consumption, low heat generation, and no magnetic interference. Structure) According to the present invention, a movable member is supported at one end and has a flight member at a free end; A latch-type piezoelectric actuator is obtained, characterized in that it is composed of a latch spring as a means for tilting the member, and an electrostrictive or piezoelectric element that faces the tilted side of the movable member and applies force to the flight member. .

(Detailed Description of Configuration) The present invention solves the problems of the prior art by adopting the above-described configuration.

First, by using an electrostrictive or piezoelectric element with high energy conversion efficiency and without copper loss or iron loss, which are the disadvantages of conventional electromagnetic systems, as a drive source for flight components, low power consumption, low heat generation, and magnetic interference are eliminated.

Moreover, the movable member can be operated like a cantilever beam or a link (by having one end supported and the other end free).

The movable member mates with a latch spring supported at a distance from the support of the movable member. At this time, the latch spring is joined so that a restoring force is applied, and the movable member is tilted to one side by the restoring force of the two-way spring. According to the configuration, when a force is applied to the movable member and the movable member passes over an extension line connecting the latch spring and the supporting portion of the movable member, the movable member undergoes a reversal action due to the force of the latch spring and is latched. . Further, the movable member is provided with a flying member, and an electrostrictive or piezoelectric element is arranged opposite to the inclined side of the movable member to apply force to the flying member, and in the initial state, either one of the electrostrictive or piezoelectric elements is disposed. and the flying parts are in contact with each other. Therefore, when a voltage is applied to an electrostrictive or piezoelectric element, the electrostrictive or piezoelectric element displaces very quickly, although slightly, so the flying member is accelerated by the electrostrictive or piezoelectric element, leaves the electrostrictive or piezoelectric element, and flies away. However, the movable member rotates accordingly. After that, when the movable member passes over the extension line connecting the latch spring and the supporting part of the movable member, the movable member is reversed by the force of the latch spring and is latched. At this time, the stroke of the flying member is caused by the electrostrictive or piezoelectric element. The amount of displacement is also much larger.

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

FIG. 1(a) is a schematic perspective view showing a refreshing example in which the present invention is applied to a relay, and FIG. 1(b) is a diagram for explaining the operation of FIG. 1(a). . In Figure 1-(a), a movable member 1 has one end rotatably supported by a base 2 and the other end free. Further, a movable contact 3 as a flying member is provided at the free end of the movable member 1, and a two-way spring 4 is provided on the movable member 1. Further, the latch spring 4 is connected to the base 2 at a distance from the support portion of the movable member 1. At this time, the movable member 1 is tilted to either side by the restoring force of the latch spring 4, and the movable contact 3 is connected to the first piezoelectric element 5 provided so as to correspond to the movable contact 3. It is supported so as to apply preload to the first fixed contact 6 bonded on the element 5.

On the other hand, a second piezoelectric element 7 is disposed opposite to the first piezoelectric element 5 and symmetrically to the supporting part of the movable member l, and a second fixed contact is disposed on the second piezoelectric element 7. 8 are joined.

In such a structure, when a voltage is applied to the first piezoelectric element 5, a small but rapid displacement occurs. At this time, the movable contact 3 supported in contact with the first fixed contact 6
receives a force from the first piezoelectric element 5, is accelerated, flies away from the first fixed contact 6, and when the movable contact 3 crosses the extension line connecting the movable member l of the base 2 and the support part of the latch spring 4, The movable member 1 is reversely operated by the return force of the latch spring 4, and the movable contact 3 is brought into contact with the second fixed contact 8 as shown in FIG. 1-(b). Next, when a voltage is applied to the second piezoelectric element 7, the movable contact 3 leaves the second fixed contact 8 and flies in the direction of the first fixed contact 6, and then reverses again and returns to the first fixed contact. In this way, the movable contact 3 is moved from the first fixed contact 6 to the second fixed contact 8,
or from the second fixed contact 8 to the first fixed contact 6)
It can be changed.

In the present invention, when a voltage is applied, the force generated by the first or second piezoelectric elements 5, 7 accelerates the movable contact 3t as a flying member, and inverts the movable member 1i. It is possible to obtain a stroke of the movable contact 3 that is several tens to hundreds of times larger than the amount of displacement of the second piezoelectric elements 5 and 7, and also to obtain a large contact force.

Furthermore, as a drive source for the movable contact 3 as a flight member,
Since it uses a piezoelectric element known for its high energy conversion efficiency, it has low power consumption, low heat generation, and eliminates magnetic interference.

Moreover, since there is no coil and the movable member 1 and the latch spring 4 perform all the latching operations as reversing springs, the structure is simple and compact.

In the above example, voltage was applied alternately to the first piezoelectric element 5 and the second piezoelectric element 7 to switch the movable contact. The movable contact 3f can also be switched by simultaneously applying a voltage. This type of usage has not been possible with conventional latch-type electromagnetic actuators.

Note that the voltage applied to the piezoelectric element needs to be raised quickly in the form of a pulse, but the pulse width may be short; for example, a pulse width of 0.1 ms is sufficient, and it does not matter if it is long. Since a piezoelectric element is electrically the same as a capacitor, it does not consume power and therefore does not generate heat even if a voltage is continuously applied for a long time. FIG. 2 is a schematic perspective view showing another embodiment to which the present invention't IJ relay is applied. In FIG. 2, the movable member 9 has a portal shape and is supported by the base IO, and the latch 4
is arranged at the center of the movable member 9. The movable member 9 is also provided with a movable contact 3 as a flying member.

Furthermore, a first piezoelectric element 5 and a second piezoelectric cable 7 are arranged so as to face the movable contact 3, and a first fixed contact 6 and a second fixed contact 8 are connected to each element. There is. Even in such a structure, the movable contact 3 can be switched from the first fixed contact 6 to the second fixed contact 8 by excitation of the first piezoelectric element 5, and the same effect as in the previous embodiment is achieved. Effects can be obtained.

FIG. 3 is a perspective view showing another embodiment, in which the movable member 1
1 is supported by a plate spring 12. Also, - movable member 1
1 is provided with a movable contact 3 and a latch spring 4. The movable member 11 can be supported by such a plate spring 12, and similar effects can be obtained in the present invention. In addition to the coil spring, the latch spring 4 may be a plate spring if a tensile force is generated.

FIG. 4 is a diagram showing an embodiment in which the present invention is applied to an optical path switch. In FIG. 4(a), the flight member 13 is provided on a movable member 14, and a mirror 15 is provided at the tip of the movable member 14. Furthermore, the movable member 14 is supported by the base 16, and the flying member 13 is in contact with the first piezoelectric element 5 due to the force of the latch spring 4. The second piezoelectric element 7 is arranged so as to be in contact with the flight member 13 when the movable member 14 performs a reversal operation, as shown in FIG. 4(b).

In such a configuration, in the state shown in FIG. When the element 5 is excited, the flying member 13 receives a force from the first piezoelectric cable 5 and flies. At the same time, the movable member 14 rotates, and the flying member 13 moves toward the movable member 14 on the base 16.
When the movable member 14 crosses the extension line connecting the support portion of the latch spring 4 and the support portion of the latch spring 4, the movable member 14 reverses itself due to the restoring force of the latch spring 4, and enters the state shown in FIG. 4(b). Therefore, due to the rotation of Mi2-15, the angle to the incident light also changes9. Incident light from the direction of arrow C goes out in the direction of arrow E as reflected light. If a voltage is applied to the second piezoelectric element 7 while the flying member 13 is still in contact with the second piezoelectric cable 7 as shown in FIG. f,)
The flying member 13 returns to the state in which it is in contact with the first piezoelectric cord 5 as shown in FIG. In this way, the optical path can be switched.

It goes without saying that even in such an embodiment of the present invention, the effects of the present invention such as simple structure, small size, low power consumption, low heat generation, and no magnetic interference are similarly exhibited. FIG. 2 is a diagram showing an example in which the method is applied to a pen lifting mechanism such as a pen recorder. In FIG. 5 1), the movable member 18 provided with the pen holder 17 is attached to the latch spring 4.
is tilted towards the first piezoelectric element 5 by the flying member 13
and the first piezoelectric element 5 are in contact with each other. Further, the second piezoelectric element 7 is arranged symmetrically with respect to the support portion of the movable member 18. Furthermore, the pen 19 is supported by the pen holder 17.

In an embodiment with such a configuration, a voltage is applied to the first pressure 11 to the piezoelectric cable 5 while the flight member 13 is in contact with the first piezoelectric cable 5 as shown in FIG. 5(a). Then, the flying member 13 receives a force from the first piezoelectric element 5 and is accelerated, and when the first piezoelectric element 5 flies away from the movable member 13 and passes through the straight line between the movable member 18 and the support part of the latch spring 4, the movable member 18 The reversing operation brings the flying member 13 into contact with the second piezoelectric element 7 as shown in FIG. 5(b). Therefore pen 1
9 can be printed from top to bottom. Further, when a voltage is applied to the second piezoelectric element 7 with the flying member 13 in contact with the second piezoelectric element 7 as shown in FIG. 5(b), the movable member 18
is reversed again and the flying member 1 as shown in Fig. 5 (a.
3 returns to the state in which it is in contact with the first piezoelectric element 5. In this way, the ben 19 can be raised and lowered.

It goes without saying that even in such an embodiment of the present invention, the effects of the present invention such as simple structure, small size, low power consumption, low heat generation, and no magnetic interference are similarly exhibited. FIG. 6 shows the present invention. It is a figure which shows one Example which applied this to the switch of a flow path. In FIG. 6 (al), the movable member 20 is tilted toward the first piezoelectric element 5 (2) by the latch spring 4, and the flying member 13 on the movable member 20 and the first piezoelectric element 5 are in contact with each other. Further, the second piezoelectric element 7 is arranged symmetrically with respect to the support portion of the movable member 20. On the other hand, the movable member 20 and the valve 21 are connected by a link 22.

In an embodiment with such a configuration, when the flying member 13 is in contact with the first piezoelectric element 5 as shown in FIG.
θ).

When the full voltage is applied to the first piezoelectric element 5 in this state, the flying member 13 receives the force from the first piezoelectric element 5 and is accelerated, the first piezoelectric element 5 flies away from the movable member 20 and the latch spring 4. When the movable member 20 passes through the straight line connecting the supporting parts, the movable member 20 reverses and the flying member 13 comes into contact with the second piezoelectric element 7 as shown in FIG. 6(b). Pushed by the link 22 connected to the movable member 20,
Close the channel. Further, when a voltage is applied to the second piezoelectric element 7 while the flight member 13 is in contact with the second piezoelectric element 7 as shown in FIG. The flying member 13 as shown in FIG.

It goes without saying that even in this embodiment of the present invention, the effects of the present invention such as simple structure, small size, low power consumption, low heat generation, and no magnetic interference are similarly exhibited.

Further, as another embodiment of the present invention, an embodiment of a latch type relay using a curved spring is shown in FIGS. , Figure 7 (bl
(1) is a diagram for explaining the operation of (1). In FIG. 7, the movable member 23 is supported at one end, free at the other end, and can rotate like a cantilever beam or a link.

On the other hand, the latch spring 24 is supported so as to be sandwiched between the free end portion of the movable member 23 and a support portion remote from the support portion of the movable member 23, and to be curved. This latch spring 24 acts similar to a compression spring to apply force to the movable member 23 so that it can be tilted to either side. In addition, in this configuration, when a force is applied to the movable member to return it in the direction of decreasing the inclination, when the extension line connecting the latch spring 24 and the support portion of the movable member 23 is passed, the movable member 23 is provided with the latch spring 24 and the movable member 23 is provided with the latch spring 24. , an electrostrictive or piezoelectric element 5゜7 that applies force to the movable contact 3 is arranged facing the inclined side of the movable member 23, and in a steady state, a fixed contact 6 on one of the electrostrictive or piezoelectric elements 5, 7 , 8 and the movable contact 3 are in contact with each other. Therefore, when a voltage is applied to the electrostrictive or piezoelectric elements 5 and 7, the electrostrictive or piezoelectric elements 5 and 7 produce a slight but very fast displacement as is well known, so the movable contact 3 The movable member 23 is accelerated by the deer, leaves the electrostrictive or piezoelectric elements 5 and 7, and flies, and the movable member 23 also rotates. Thereafter, when the rotating member 23 passes over the extension line connecting the latch spring 24 and the support portion of the movable member 23, the movable member 23 is reversed from its previous position to the reflection side by the compressive force of the latch spring 24 and is latched. At this time, the stroke of the movable contact 3 or the movable member 23 is extremely large compared to the amount of displacement generated by the electrostrictive or piezoelectric element. In this way, the present invention can also be applied to a latch spring 24 in which a leaf spring is bent and its return force is used.

Further, the present invention can be applied to a relay in which the latch spring 24 and the movable member 23 are integrated as shown in FIGS. 8 and 9, and similar effects can be obtained.

Note that the present invention can be applied not only to the above implementation but also to various latch type actuators and similar effects can be obtained.

The effects of the present invention are achieved by a structure in which two springs with different support ends are connected to a movable member provided with a flying member, and a piezoelectric element for making the flying member fly is arranged. The present invention also includes a single-plate piezoelectric element having a vertical effect or a horizontal effect.

Similar effects can be obtained and applied to laminated piezoelectric elements and even electrostrictive elements.

In addition, in the present invention, two piezoelectric elements are all arranged on both sides of the movable member, but by using a return means k)1
It is also possible to use a single piezoelectric element.

(Effect of the invention) According to the present invention, the structure is simple, small, and low power.

A latch-type piezoelectric actuator with low heat generation and no magnetic interference can be obtained.

[Brief explanation of drawings]

Fig. 1 (ta+) is a diagram showing an embodiment in which the present invention is applied to a relay, Fig. 1 (b) is a diagram for explaining the operation of (a), and Fig. 2 is a diagram showing an embodiment in which the present invention is applied to a relay. FIG. 3 is a diagram showing another embodiment of the present invention. FIG. 4 is a diagram showing an embodiment in which the present invention is applied to an optical path switch.
The figures show an embodiment in which the present invention is applied to a pen lifting mechanism such as a pen recorder, FIG. 6 shows an embodiment in which the present invention is applied to a flow path switch, and FIGS. 8 and 9 are diagrams showing other embodiments in which the present invention is applied to a relay. Each symbol in the figure indicates the following content. 1+ 9t 11+ 14+ 18t 20
t 23...Movable member s L 10t 16.
... Base, 3... Movable contact, 4.24... Latch spring, 5... First piezoelectric element, 6... First fixed contact, 7... Second piezoelectric element, 8... Second fixed contact, 12... Leaf spring, 13... Flight member, 15...
Mi7-, 17... Pen holder, 19... Pen, 21
... Valve, 22... Link. ;11't Figure (a) (b) O 5 Figure (a) (b) 21-6 Figure (a) 7 Second piezoelectric element (b) 78 Figure 79 Figure □ - 23 Movable member

Claims (1)

[Claims] A movable member having one end supported and a free end having a flight member, one end connected to the movable member, and the other end connected at a distance to a supporting portion of the movable member, and a means for tilting the movable member. A latch type piezoelectric actuator comprising: a latch spring; and an electrostrictive or piezoelectric element that faces the inclined side of the movable member and applies force to the flight member.