JPH057810B2 - - Google Patents

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, an electromagnetic actuator using a coil has been used as a latch-type actuator. However, electromagnetic actuators generate a magnetic field by energizing a coil and use the magnetic force to move a movable member, so they require a large amount of input energy and have problems such as heat generation and magnetic interference. Also, since it uses a coil, it is 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 which has a simple structure, is small in size, has low power consumption, low heat generation, and is free from magnetic interference.

(Structure of the Invention) The latch-type piezoelectric actuator of the present invention includes a leaf spring having a flying member, a support portion that supports the leaf spring in a curved manner, and a support portion that supports the flying member so as to be opposed to a convex surface of the curved leaf spring. and a means for applying a voltage with a steep rise to the piezoelectric element, and the flight member receives a force from the piezoelectric element by applying the steep voltage to the piezoelectric element. It is characterized in that the leaf spring is reversed by flying and flying.

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

First, by using a piezoelectric element, which is known for its high energy conversion efficiency, as the driving source for the flying member, it uses low power, generates little heat, and eliminates magnetic interference.

In addition, by applying an axial force to a leaf spring and bending it, the leaf spring becomes a reversible spring, and when the flight member provided on the leaf spring passes through a straight line connecting both ends of the leaf spring, the leaf spring reverses and latches. be done.

When a voltage is applied to the piezoelectric element, the piezoelectric element is slightly displaced very quickly, so the flying member receives a force from the piezoelectric element and is accelerated, leaving the piezoelectric element and flying. When the flying member passes through a straight line connecting both ends of the leaf spring, the leaf spring is reversed and latched, making it possible to obtain a stroke of the flying member that is much longer than the amount of displacement of the piezoelectric element.

Furthermore, since no coil is used and the reversal spring is also composed of a leaf spring, the structure is simple and compact.

(Example) Hereinafter, an example of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a diagram showing an embodiment in which the present invention is applied to a relay. In FIG. 1, a movable contact 2 is provided as a flight member near the center of a leaf spring 1, and both ends of the leaf spring 1 are inserted into grooves 3a and 3b as supporting parts provided in a mounting member 3, and the An axial force is applied to the spring 1, and the leaf spring 1 is curved. Also, one end 4 of the first piezoelectric element 4 in the expansion/contraction direction (direction of arrow A)
The first fixed contact 5 is connected to a, the second fixed contact 7 is connected to one end 6a of the second piezoelectric element 6 in the expansion/contraction direction (arrow B direction), and the first fixed contact 5 and the second The fixed contacts 7 are arranged opposite to each other with the movable contacts 2 interposed therebetween. Furthermore, as shown in FIG. 1a, the first piezoelectric element 4 is connected to the first fixed contact 5 disposed on the curved convex side of the leaf spring 1 so that the movable contact 2 contacts the first fixed contact 5 with a certain preload. The end 4b is fixed to the mounting member 3. The other end 6b of the second piezoelectric element 6 is fixed to the mounting member 3 so that the second fixed contact 7 is in a symmetrical position with respect to the first fixed contact 5 with respect to the straight line connecting both ends of the leaf spring 1. There is.

When a voltage is applied to the first piezoelectric element 4 in a state where the movable contact 2 is in contact with the first fixed contact 5 as shown in FIG. while displacing at a very high speed. Then, the movable contact 2 as a flying member that is in contact with the first fixed contact 5 is accelerated by receiving the force from the first piezoelectric element 4, flies away from the first fixed contact 5, and touches both ends of the leaf spring 1. The plate spring 1 is reversed and the movable contact 2 is in contact with the second fixed contact 7 as shown in FIG. 1b. Also, the first
The movable contact 2 is the second fixed contact 7 as shown in Figure b.
When a voltage is applied to the second piezoelectric element 6 from a state in which it is in contact with the movable contact 2, the movable contact 2 receives a force from the second piezoelectric element 6 in the direction of arrow B and is accelerated to the second fixed contact 7.
The leaf spring 1 moves in the opposite direction again, leaving the movable contact 2 in contact with the first fixed contact 5 as shown in FIG. 1A. In this way, the movable contact 2 can be switched from the first fixed contact 5 to the second fixed contact 7 or from the second fixed contact 7 to the first fixed contact 5.

In the present invention, the movable contact 2 as a flight member is accelerated by the force generated by the first or second piezoelectric elements 4, 6 when a voltage is applied, and the fly leaf spring 1 is reversed. It is possible to obtain a stroke of the movable contact 2 that is several tens to hundreds of times larger than the amount of displacement of the second piezoelectric elements 4 and 6, and also to obtain a large contact force.

Furthermore, since a piezoelectric element known for its high energy conversion efficiency is used as a drive source for the movable contact 2 as a flying member, there is no magnetic interference with low power consumption and low heat generation.

Furthermore, since there is no coil and the leaf spring is turned into a reversing spring by applying an axial force to perform the latching action, the structure is simple and compact.

In the above example, to switch the movable contact 2,
Although a voltage is applied alternately to the first piezoelectric element 4 and the second piezoelectric element 6, the movable contact 2 can also be applied by simultaneously applying a voltage to the first piezoelectric element 4 and the second piezoelectric element 6. Can be switched. Such usage has not been possible with conventional latch type electromagnetic actuators.

Note that the voltage applied to the piezoelectric element must be started up in a pulsed manner, but the pulse width may be short. For example, a pulse width of 0.1 ms is sufficient, and a longer pulse width does not matter. Since a piezoelectric element is electrically the same as a capacitor, it does not consume power even if voltage is continuously applied for a long time, and therefore does not generate heat.

FIG. 2 is a perspective view showing another embodiment in which the present invention is applied to a relay, and the shape of the mounting member 8 is different from that of the previous embodiment. It goes without saying that the effects of the present invention can be similarly exhibited regardless of the shape of the mounting member.

FIG. 3 is a diagram showing an embodiment in which the present invention is applied to a display device. In FIG. 3a, the leaf spring 1 connected to the flight member 9 and the first display board 11 is inserted into grooves 3a and 3b as supporting parts provided in the mounting member 3, and is bent by receiving an axial force. A flying member 9 is in contact with a first piezoelectric element 4 connected to a mounting member 3. The second piezoelectric element 6 is connected to the mounting member 3 in such a way that the flight member 9 comes into contact with it when the leaf spring 1 is reversed, as shown in FIG. 3b. Further, the second display plate 12 is attached to the mounting member 3 at a position where the first display plate 11 overlaps when the leaf spring 1 is reversed. Furthermore, a window 10 is provided above the second display board 12, and only the window 10 can be seen from the outside.

Now, as shown in FIG. 3a, the first display board 11
A case will be explained in which the characters "in use" are written on the second display board 12 and the characters "empty" are written on the second display board 12. When the flying member 9 is in contact with the first piezoelectric element 4 as shown in FIG. 3a, the word "sky" written on the second display board 12 can be seen from the outside through the window 10. . When a voltage is applied to the first piezoelectric element 4 from this state, the flight member 9
The flying member 9 flies away from the first piezoelectric element 4 and passes through the straight line connecting both ends of the leaf spring 1, causing the leaf spring 1 to perform a reversal operation and the flying member 9 to move to the second position as shown in FIG. 3b. The first display plate 1 is in contact with the second piezoelectric element 6.
1 overlaps on the second display board 12. Therefore, the words "in use" written on the first display board 11 can be seen from the outside through the window 10. Further, when a voltage is applied to the second piezoelectric element 6 from a state where the flight member 9 is in contact with the second piezoelectric element 6 as shown in FIG. The flying member 9 returns to the state in which it is in contact with the first piezoelectric element 4 as shown in FIG.
2 The word "sky" written above becomes visible.

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.

FIG. 4 is a diagram showing an embodiment in which the present invention is applied to an optical path switch. In FIG. 4a, the flying member 9 is provided at the center of the leaf spring 1, and the mirror 13 is provided intermediate the flying member 9 and the fixed end 3a of the leaf spring 1. Further, the leaf spring 1 is inserted into grooves 3a and 3b as supporting parts provided in the mounting member 3, and is bent by receiving an axial force, and the flight member 9 is connected to the first piezoelectric element 4 connected to the mounting member 3. are in contact with each other. The second piezoelectric element 6 is connected to the mounting member 3 so that the flight member 9 comes into contact with it when the leaf spring 1 reverses, as shown in FIG. 4b.

In an embodiment of such a configuration, when the flying member 9 is in contact with the first piezoelectric element 4 as shown in FIG. 4a, the leaf spring 1 is curved toward the first piezoelectric element 4. Therefore, the incident light from the direction of arrow C is reflected by the mirror 13 and goes out in the direction of arrow D as reflected light. When a voltage is applied to the first piezoelectric element 4 in this state, the flight member 9
The flying member 9 flies away from the first piezoelectric element 4 and passes through a straight line connecting both ends of the leaf spring 1, causing the leaf spring 1 to perform a reversal operation, as shown in FIG. 4b. It comes into contact with the second piezoelectric element 6. Therefore, the leaf spring 1 curves toward the second piezoelectric element 6, and the angle of the mirror 13 with respect to the incident light changes, so that the incident light from the direction of the arrow C becomes reflected light in the direction of the arrow E. go. Further, when a voltage is applied to the second piezoelectric element 6 from a state where the flying member 9 is in contact with the second piezoelectric element 6 as shown in FIG. 4b,
The leaf spring 1 reverses again and returns to the state in which the flying member 9 is in contact with the first piezoelectric element 4 as shown in FIG. 4a. In this way, the optical path can be switched.

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.

FIG. 5 is a diagram showing an embodiment in which the present invention is applied to a pen lifting mechanism such as a pen recorder. In FIG. 5a, the leaf spring 1 to which the pen holder 14 is connected
is a groove 3 as a support provided in the mounting member 3.
a, 3b, and is bent toward the first piezoelectric element 4 by receiving an axial force. A flying member 9 provided on the leaf spring 1 is in contact with a first piezoelectric element 4 connected to the mounting member 3. The second piezoelectric element 6 is
As shown in FIG. 5b, when the leaf spring 1 is reversed, it is connected to the mounting member 3 so that the flight member 9 comes into contact with it. Further, the pen 15 is supported by the pen holder 14.

In an embodiment with such a configuration, when a voltage is applied to the first piezoelectric element 4 while the flying member 9 is in contact with the first piezoelectric element 4 as shown in FIG. 5a, the flying member 9 It is accelerated by the force from the first piezoelectric element 4, flies away from the first piezoelectric element 4, passes through a straight line connecting both ends of the leaf spring 1, and the leaf spring 1 performs a reverse operation, as shown in FIG. 5b. The flying member 9 is in contact with the second piezoelectric element 6. Therefore, the pen 15 can descend from the top to the bottom to print. Further, when a voltage is applied to the second piezoelectric element 6 with the flight member 9 in contact with the second piezoelectric element 6 as shown in FIG. 5b, the leaf spring 1 performs the reverse operation again as shown in FIG. 5a The flying member 9 returns to the state in which it is in contact with the first piezoelectric element 4. In this way, the pen 15 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 can be similarly exhibited.

FIG. 6 is a diagram showing an embodiment in which the present invention is applied to a flow path switch. In FIG. 6a, the leaf spring 18 provided with the two flight members 16 and 17 has a groove 19a as a support provided in the mounting member 19,
The flying members 16 and 17 are inserted into the piezoelectric member 19b and curved by receiving an axial force, and are in contact with two first piezoelectric elements 20 and 21 connected to the mounting member 19. The two second piezoelectric elements 22, 23 are connected to the mounting member 19 so that when the leaf spring 18 is reversed, the two flying members 16, 17 are in contact with each other, as shown in FIG. 6b. Furthermore, the valve 24 that opens and closes the flow path is a leaf spring 1.
It is connected to the center of 8 by a link 25.

In an embodiment with such a configuration, when the flying members 16, 17 are in contact with the first piezoelectric elements 20, 21 as shown in FIG. 6a, the fluid does not flow because the valve 24 does not close the flow path. It can flow like arrow F. In this state, the first piezoelectric element 20,
When voltage is applied to 21, the flying members 16 and 17 are accelerated by the force from the first piezoelectric elements 20 and 21, fly away from the first piezoelectric elements 20 and 21, and pass through a straight line connecting both ends of the leaf spring 18. The leaf spring 18 reverses and moves the flying member 16 as shown in FIG. 6b.
17 is in contact with the second piezoelectric elements 22 and 23. The valve 24 is then pushed by the link 25 connected to the leaf spring 18, closing the flow path. Further, when a voltage is applied to the second piezoelectric elements 22, 23 with the flying members 16, 17 in contact with the second piezoelectric elements 22, 23 as shown in FIG. Then, the flying members 16 and 17 as shown in FIG. 6a come into contact with the first piezoelectric elements 20 and 21, opening a flow path.

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.

It should be noted that the present invention can be applied not only to the above-mentioned embodiments but also to various latch-type actuators with similar effects. The effects of the present invention are achieved by applying an axial force to a leaf spring provided with a flying member to curve it, and creating a structure in which a piezoelectric element is arranged to fly the flying member.

Furthermore, in the above embodiment, piezoelectric elements were arranged on both the curved convex side and the opposite concave side of the leaf spring, but if the leaf spring return means is used, the curved convex side of the leaf spring Even if the piezoelectric element is arranged only on the side, the effects of the present invention can be similarly exhibited.

Further, in the present invention, similar effects can be obtained not only by a single-plate piezoelectric element having a longitudinal effect or a lateral effect, but also by a laminated piezoelectric element or an electrostrictive element.

(Effects of the Invention) According to the present invention, the structure is simple, small, low power,
A latch-type piezoelectric actuator with low heat generation and no magnetic interference can be obtained.

[Brief explanation of drawings]

Fig. 1 is a diagram showing one embodiment in which the present invention is applied to a relay, Fig. 2 is a diagram showing another embodiment in which the present invention is applied to a relay, and Fig. 3 is a diagram showing an embodiment in which the present invention is applied to a display. FIG. 4 is a diagram showing an embodiment in which the present invention is applied to an optical path switch; FIG. 5 is a diagram showing an embodiment in which the present invention is applied to a pen lifting mechanism such as a pen recorder; FIG. 6 is a diagram showing an embodiment in which the present invention is applied to a flow path switch. In the figure, 1, 18...plate spring, 2...movable contact, 3, 8, 19...mounting member, 4, 20, 2
1... First piezoelectric element, 5... First fixed contact,
6, 22, 23... Second piezoelectric element, 7... Second fixed contact, 9, 16, 17... Flight member, 10
... window, 11 ... first display board, 12 ... second display board, 13 ... mirror, 14 ... pen holder,
15...Pen, 24...Valve, and 25...Link are shown, respectively.

Claims (1)

[Claims] 1 A leaf spring having a flight member, a support portion that supports the leaf spring in a curved manner, a piezoelectric element that applies force to the flight member in opposition to a convex surface of the curved leaf spring, and a piezoelectric element that applies a force to the flight member, and a and a means for applying a steep voltage to the piezoelectric element, and by applying the steep voltage to the piezoelectric element, the flying member receives a force from the piezoelectric element and flies, and by flying, the leaf spring is reversed. A latch-type piezoelectric actuator that operates.