JPH07101588B2 - Displacement element and relay device using the same - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a displacement element and a relay device using the displacement element, and more specifically, from an antiferroelectric phase to a ferroelectric phase when a predetermined electric field is applied. The present invention relates to a displacement element capable of causing a digital displacement by a phase transition and maintaining a ferroelectric phase even after an electric field is cut off, and a keep relay type relay device using the displacement element.

[Prior Art] Conventionally, a relay that opens and closes an electrical contact is mainly of an electromagnetic drive type, and an electrical signal is applied to a coil, and a movable contact piece is moved by electromagnetic force generated to open and close the electrical contact. It is operating.

In such an electromagnetic relay, there is a limit to miniaturization and it is necessary to respond at high speed. Therefore, a piezoelectric relay using a piezoelectric bimorph element (Piezo Electric Products) ) Has been used. This piezoelectric relay uses a piezoelectric bimorph element in which two piezoelectric elements polarized in opposite directions are bonded together, and a snap drive spring or a permanent magnet is used to mechanically make the piezoelectric bimorph element a monostable or bistable state. The bimorph element is moved according to the electric signal to perform the relay operation.
In addition, a highly sensitive snap operation switch that combines a piezoelectric bimorph element and a spring, transmits deformation of the piezoelectric bimorph to a movable piece biased by the spring, and can be turned on and off within several tens of μm has been developed. In addition, a piezoelectric relay in which a plurality of piezoelectric actuators are stacked in layers to improve high-speed response is also known (for example, “OMRON Techinics No.70p52 (198
3) Sato et al or Jpn.J.Appl.Phys.24 Suppl.24−
3,190 (1985) S. Mitsuhashi et al ").

[Problems to be Solved by the Invention] However, in such a conventional electromagnetic relay, there is a problem in that power consumption is large to drive the relay, driving time is generated, and miniaturization and integration cannot be achieved. It was In addition, the piezoelectric relay requires a separate holding device to hold the relay contact in the on or off state, which consumes power and makes the entire device large, which naturally limits the miniaturization and integration. there were.

Therefore, the present invention has been made to solve such a problem, and is a displacement element that consumes less power, generates a small amount of heat, and can hold a displacement state without using a holding device, and the displacement element. It is an object of the present invention to provide an existing relay device.

Furthermore, in addition to the above-mentioned problems, a displacement device itself detects a temperature, and therefore, a relay device capable of returning a displacement state to an initial strain state when a predetermined temperature is reached without using another temperature detection mechanism. It is a thing.

[Means for Solving the Problem] In order to solve such a problem, the present invention digitally displaces a phase transition from an antiferroelectric phase to a ferroelectric phase induced when a predetermined electric field is applied. , A ferroelectric shape-memory ceramic element that maintains a ferroelectric phase even after the electric field is cut off, and electrodes formed on both sides of the shape-memory ceramic element, and a predetermined electric field is applied to the shape-memory ceramic element. The shape memory ceramics element is digitally displaced so that the displacement state can be continued even after the electric field is cut off.

Further, according to the present invention, the phase transition from the antiferroelectric phase to the ferroelectric phase induced when a predetermined electric field is applied causes digital displacement, and the ferroelectric phase is maintained even after the electric field is cut off. A ferroelectric shape memory ceramics element and electrodes formed on both surfaces of the first and second shape memory ceramics elements, wherein the first and second shape memory ceramics elements are laminated, A configuration is also adopted in which a predetermined electric field is applied to the shape memory ceramics element 1 to displace it, and the displacement state is continued even after the electric field is cut off.

Further, according to the present invention, the ferroelectric shape memory property that is digitally displaced by the phase transition from the antiferroelectric phase to the ferroelectric phase induced when a predetermined electric field is applied and maintains the ferroelectric phase even after the electric field is cut off. A laminated body in which a plurality of ceramic elements are laminated,
Insulating parts arranged in alternate stages on the stack so as to be zigzag on each side on both sides of the stack, and a metal conductor part continuously formed in the stacking direction through the insulating part,
A configuration is also adopted in which a predetermined electric field is applied to the metal conductor portion to displace the laminated body in the laminating direction, and the displacement state is continued even after the electric field is cut off.

Further, according to the present invention, the ferroelectric shape memory property is digitally displaced by the phase transition from the antiferroelectric phase to the ferroelectric phase induced when a predetermined electric field is applied, and the ferroelectric phase is maintained even after the electric field is cut off. It has a ceramic element and a mover that moves according to digital displacement of the shape memory ceramic element to turn on and off electrical contacts, and applies a predetermined electric field to digitally displace the shape memory ceramic element to turn electrical contacts on and off. In addition to reversing from one of the normal states, a configuration is adopted in which the ferroelectric phase is maintained and the reversal state is continued even after the electric field is cut off.

Further, according to the present invention, the ferroelectric shape memory property that is digitally displaced by the phase transition from the antiferroelectric phase to the ferroelectric phase induced when a predetermined electric field is applied and maintains the ferroelectric phase even after the electric field is cut off. A laminated body in which a plurality of ceramic elements are laminated,
Insulating portions arranged at alternate stages on each side of the laminated body in a zigzag manner on each side, metal conductor portions continuously formed in the laminating direction through the insulating portion, and the laminated body It has a mover that moves according to the digital displacement of the body and turns on and off the electric contact, and applies a predetermined electric field to the metal conductor part to displace the laminated body in the laminating direction to turn the electric contact on and off from the normal state. In addition, a structure was adopted in which the ferroelectric phase was maintained and its inversion state continued even after the electric field was cut off.

Further, according to the present invention, the ferroelectric shape memory property that is digitally displaced by the phase transition from the antiferroelectric phase to the ferroelectric phase induced when a predetermined electric field is applied and maintains the ferroelectric phase even after the electric field is cut off. It has a ceramic element and a mover that moves according to digital displacement of the shape memory ceramic element to turn on and off electrical contacts, and applies a predetermined electric field to digitally displace the shape memory ceramic element to turn electrical contacts on and off. While reversing from any normal state,
We also adopted a configuration in which the electrical contacts can be returned to the normal state again at a predetermined temperature.

Further, according to the present invention, the ferroelectric shape memory property is digitally displaced by the phase transition from the antiferroelectric phase to the ferroelectric phase induced when a predetermined electric field is applied, and the ferroelectric phase is maintained even after the electric field is cut off. A laminated body in which a plurality of ceramic elements are laminated,
Insulating portions arranged at alternate stages on each side of the laminated body in a zigzag manner on each side, metal conductor portions continuously formed in the laminating direction through the insulating portion, and the laminated body It has a mover that moves according to the digital displacement of the body and turns on and off the electric contact, and applies a predetermined electric field to the metal conductor part to displace the laminated body in the laminating direction to turn the electric contact on and off from the normal state. In addition, a configuration was adopted in which the electrical contacts can be returned to the normal state again at a predetermined temperature.

[Operation] In such a configuration, when a predetermined predetermined electric field is applied to the ferroelectric shape memory ceramics element, the shape memory ceramics element undergoes a phase transition from the antiferroelectric phase to the ferroelectric phase, whereby the shape memory Ceramic elements are digitally displaced. In that case, the shape-memory ceramic element can maintain the ferroelectric phase even after the electric field is cut off depending on its composition, and can maintain its displaced state, and the effect of memorizing the strained state of the ferroelectric phase can be obtained. In the present invention, this property is utilized to form the displacement element. When this is used in a relay device, a mover that moves according to the digital displacement of such a shape-memory ceramic element to turn on / off electrical contacts is provided, and a predetermined electric field is applied to the shape-memory ceramic element to digitally move it. The electric contact is turned on through the mover by turning the electric contact, and the ferroelectric phase is maintained and the on state is continued even after the electric field is cut off.

Further, in such a relay device, a predetermined electric field is applied to the shape memory ceramics element to digitally displace it, and the electric contact is reversed from the on (or off) state via the mover and the predetermined temperature is set. The electrical contact is restored to the on (or off) state again.

[Examples] The present invention will be described in detail below with reference to the examples shown in the drawings.

For example, when an electric field is applied to a lead zirconate titanate-based ceramic element, the antiferroelectric phase of the ceramic element suddenly undergoes a phase transition to a ferroelectric phase above a certain critical electric field. At that time, a large linear expansion strain of about 0.1% is exhibited relatively isotropically, and it is known that the ceramic element is digitally displaced by this phase transition. In this case, it has been found that the shape change of the ceramics includes a type 1 material that returns to the original state when the electric field is cut off, and a type 2 material that maintains the ferroelectric phase state even when the electric field is cut off. There is.

FIGS. 1 (a) to 1 (c) show, for example, a ferroelectric shape represented by (Pb0.99Nb0.02) [(Zr0.6Sn0.4) 1-y Tiy] 0.98O3 (hereinafter referred to as PNZST). The electric field induced strain characteristics (lateral effect) when an electric field is applied to the memory ceramics are illustrated.

Fig. 1 (a) shows the characteristics when y = 0.060 and the electric field is V2.
At that time, the antiferroelectric phase undergoes a phase transition to the ferroelectric phase, causing a strain displacement of ΔL. The displacement amount is maintained until the electric field is reduced from V2 to V1, and a typical double hysteresis curve is formed, and the displacement returns to the original state due to the reduction of the electric field, so that the material is the first-type material described above. In this case, the amount of change in the phase transition (ΔL / L = 8x1
Compared with 0 ^-4 , the electric field dependence of the strain in the antiferroelectric state or the ferroelectric state is small, and the on / off state of the strain is realized, and it can be used as a "digital displacement element".

Composition with slightly higher titanium content than the PNZST system described above (y
= 0.063), once the ferroelectric phase is induced, the first
As shown in FIG. 9B, even if the electric field is Vo = 0, the antiferroelectric phase does not return, and the "effect of storing the strained state of the ferroelectric phase" is exhibited. This becomes a material of the second kind, and a reverse bias electric field must be applied in order to restore the original antiferroelectric phase.

Further, as shown in FIG. 1 (c), when the titanium content was further increased (y = 0.065), the ferroelectric phase once induced was no longer the antiferroelectric phase in the cycle of increasing or decreasing the electric field. To get the initial strained state without returning to
It is necessary to anneal up to 50 ℃.

The present invention relates to the second type material (y = 0.063) having the above-mentioned “effect of memorizing the strain state of the ferroelectric phase” and the third type material (y = having the effect of returning to the initial strain state due to temperature rise).
0.065) is used to form the displacement element. An example of a displacement element formed in this way is shown in FIG. In the figure, the second type material (y = 0.06) having the "effect of memorizing the strain state of the ferroelectric phase" is shown.
3) Sintered bulk consisting of 0.2mm thickness, 22mm length, 8m width
A rectangular sample of m is cut out to form shape memory ceramics elements 1 and 2, silver electrodes 3, 4 and 5 are baked, respectively, and two shape memory ceramics elements are bonded together, and the holding member 6 is formed. Then, the displacement element 10 was manufactured by holding.

In such a structure, as shown in FIG.
Apply a voltage of 500V. At this time, the shape memory ceramics element 1 is digitally displaced in the X direction by the phase transition from the antiferroelectric phase to the ferroelectric phase, and the displacement amount is about 100 μm as shown in FIG. After that, even if the applied voltage is set to 0, the shape-memory ceramic element 1 does not return to the original state, maintains the ferroelectric phase and maintains the displaced state, and exhibits shape-memory characteristics. In order to return the shape memory ceramic element to its original state, a reverse voltage of about 100V must be applied. From FIG. 3, in this displacement element 10,
Approximately 50 μm in anti-ferroelectric phase off state and ferroelectric phase on state
The above displacement difference is obtained.

FIG. 4 shows an embodiment in which the displacement element 10 shown in FIG. 2 is used as a relay. In the figure, the displacement element 10 having the configuration shown in FIG. 2 is held by a holding member 12 and attached to the base 11. The displacement induced by applying a predetermined electric field (about 500 V) to the displacement element 10 is the leaf-shaped spring 13
Transmitted through the armature 14 to cause the mover 14 to be displaced in a snap manner, thereby turning on the electric contact 15. Even if the voltage application is interrupted after the contact is turned on in this way, the displacement element 10
The shape-memory ceramic of (1) maintains its ferroelectric phase and can be kept in the ON state without requiring a separate holding circuit. To release this on state and turn it off, a reverse voltage (about -100V) may be applied. This relay turns on and off with a delay time of 10 msec with respect to the application of a step electric field of -100 V and 500 V, and a highly responsive keep relay (a relay that can maintain the ON state even when the drive input power is cut off) is obtained.

FIG. 5 shows another embodiment of the present invention. In the case of this embodiment, the displacement element is digitally displaced by the phase transition from the antiferroelectric phase to the ferroelectric phase induced when a predetermined electric field is applied, and maintains the ferroelectric phase even after the electric field is cut off. It is composed of a laminated body 30 in which a plurality of body shape memory ceramic elements 20 are laminated. Insulating portions 21 are arranged on both side surfaces of this laminated body at alternate stages so that each side surface is staggered. Further, a metal conductor portion 23 which is formed continuously through the insulating portion 21 in the stacking direction is formed. in this case,
Shape memory ceramic element 20 has a thickness of 0.2 mm
Individually stacked.

In such a configuration, a predetermined electric field (approx.
When 500 V) is applied, digital displacement is generated in each shape memory ceramic element 20 of the laminated body 30 and accumulated, and the laminated body is displaced in the X and X'directions. In that case, similarly to the embodiment of FIG. 2, the displacement element formed of the laminated body can continue its displacement state even after the electric field is cut off. Further, in order to return to the original state, similarly, for example, a voltage of about 100 V is applied in the reverse direction.

FIG. 6 shows an embodiment in which a displacement element composed of the laminated body 30 of FIG. 5 is used for a relay. In the figure, the laminated body 30 includes a push-up part 32 attached to a substrate 31, a support 33 attached to the substrate 31, and a support 34 attached to the first movable part 35.
It is supported between the push-up parts 36 and 37 via. The first movable portion 35 is connected to the substrate 31 via the hinge portion 38.
Further, the second movable portion 40 is connected to the first movable portion via the hinge portion 39. Further, the arm 41 is connected to the second movable portion via the substrate 31 and the ring spring 42 via the ring spring 43.

When an electric field of about 500 V is applied to the laminated body 30 in such a configuration, the shape memory ceramic element of the laminated body is displaced in the X direction, and this displacement is caused by the push-up portions 36, 37 and the first movable portion 3.
5, transmitted to the arm 41 via the second movable portion 40 and the ring springs 42 and 43, and displaces the arm 41 in the Y direction. In that direction, an electrical contact 44 is arranged, which turns it on. Since this shape memory ceramic element 20 maintains the ferroelectric phase even after the electric field is cut off, this on state can be continued until a reverse bias is applied. Therefore, a keep relay similar to the embodiment shown in FIG. 4 can be constructed.

The displacement element is not limited to the second type material (y = 0.063) having the “effect of memorizing the strain state of the ferroelectric phase”, but the third type having the “effect of returning to the initial strain state due to temperature rise”. A material (y = 0.065) may be used. The embodiment of the keep relay using the displacement element of the third type material is the fourth embodiment.
The relay device can be configured in the same manner as in FIG. 6 and FIG. 6, and in this relay device, the displacement element itself can detect the temperature and turn off the electrical contact. Therefore, this relay device can function as a multifunctional composite device having an electric contact on / off mechanism and an on-state holding mechanism as well as a temperature detection and off mechanism.

[Effect] As described above, according to the present invention, a predetermined electric field is applied to the shape memory ceramic element to digitally displace the shape memory ceramic element, and the displacement state can be continued even after the electric field is cut off. Therefore, by utilizing the effect of storing the strain state of the ferroelectric phase, a displacement element with low power consumption and high response can be obtained.

When this displacement element is used in a relay device, the ferroelectric phase can be maintained and the ON state can be continued even after the electric field is cut off, so the displacement state can be maintained without using a separate holding circuit, and high responsiveness is achieved. Thus, it is possible to obtain a miniaturized relay device with low power consumption.

Furthermore, if a third-class material (y = 0.065) that "obtains an initial strain state by temperature rise" is used as the displacement element, the displacement can be achieved without using any other temperature detection mechanism when turning off the electrical contact. The element itself can detect a predetermined temperature and turn off the contact, so that a temperature detection relay can be obtained.

[Brief description of drawings]

1 (a) to 1 (c) are characteristic diagrams showing the electric field distortion characteristics of the shape memory ceramics element used in the present invention, and FIG. 2 is a configuration diagram showing the configuration of the displacement element of the present invention. FIG. 3 is a characteristic diagram showing displacement characteristics of the displacement element of FIG.
FIG. 5 is a perspective view showing a configuration of a relay using the displacement element of FIG. 2, and FIGS. 5 (a) and 5 (b) are a sectional view and a perspective view of an embodiment in which a shape memory ceramics element is a laminated body. , Sixth
The drawing is a cross-sectional view showing a configuration of a relay using the laminated body of FIG. 1, 2 ... Shape-memory ceramic element 3, 4, 5 ... Electrode 10 ... Displacement element 20 ... Shape-memory ceramic element 21 ... Insulation part 22 ... Metal conductor part

Claims (7)

[Claims] 1. A ferroelectric shape memory ceramic which is digitally displaced by a phase transition from an antiferroelectric phase to a ferroelectric phase induced when a predetermined electric field is applied, and maintains the ferroelectric phase even after the electric field is cut off. An element and electrodes formed on both sides of the shape-memory ceramic element, a predetermined electric field is applied to the shape-memory ceramic element to digitally displace the shape-memory ceramic element,
A displacement element characterized in that the displacement state can be continued even after the electric field is cut off. 2. A first and second ferroelectric layer, which is digitally displaced by a phase transition from an antiferroelectric phase to a ferroelectric phase induced when a predetermined electric field is applied, and maintains the ferroelectric phase even after the electric field is cut off. A dielectric shape memory ceramics element, and electrodes formed on both surfaces of the first and second shape memory ceramics elements, wherein the first and second shape memory ceramics elements are laminated to form a first A displacement element characterized by being capable of being displaced by applying a predetermined electric field to the shape memory ceramic element of (1) and continuing the displacement state even after the electric field is cut off. 3. A ferroelectric shape memory ceramic which is digitally displaced by a phase transition from an antiferroelectric phase to a ferroelectric phase induced when a predetermined electric field is applied and maintains the ferroelectric phase even after the electric field is cut off. A laminated body in which a plurality of elements are laminated, an insulating portion arranged on each side surface of the laminated body in a staggered manner on each side surface, and an insulating portion which is continuous in the laminating direction through the insulating portion. Displacement element comprising a metal conductor part formed by applying a predetermined electric field to the metal conductor part to displace the laminate in the stacking direction, and the displacement state can be continued even after the electric field is cut off. . 4. A ferroelectric shape memory ceramic that is digitally displaced by a phase transition from an antiferroelectric phase to a ferroelectric phase induced when a predetermined electric field is applied and maintains the ferroelectric phase even after the electric field is cut off. An element and a mover that moves according to a digital displacement of the shape memory ceramic element to turn on / off an electric contact, and applies a predetermined electric field to digitally displace the shape memory ceramic element to turn on / off the electric contact. A relay device which is capable of reversing from the normal state and maintaining the ferroelectric phase after the electric field is cut off so that the reversal state can be continued. 5. A ferroelectric shape memory ceramic which is digitally displaced by a phase transition from an antiferroelectric phase to a ferroelectric phase induced when a predetermined electric field is applied and maintains the ferroelectric phase even after the electric field is cut off. A laminated body in which a plurality of elements are laminated, an insulating portion arranged on each side surface of the laminated body in a staggered manner on each side surface, and an insulating portion which is continuous in the laminating direction through the insulating portion. And a mover that moves according to the digital displacement of the laminated body to turn on and off electrical contacts, and applies a predetermined electric field to the metallic conductor portion to displace the laminated body in the laminating direction. A relay device capable of reversing an electric contact from a normal state of either on or off, maintaining a ferroelectric phase and continuing the reversal state even after electric field interruption. 6. A ferroelectric shape memory ceramic that is digitally displaced by a phase transition from an antiferroelectric phase to a ferroelectric phase induced when a predetermined electric field is applied and maintains the ferroelectric phase even after the electric field is cut off. An element and a mover that moves according to a digital displacement of the shape memory ceramic element to turn on / off an electric contact, and applies a predetermined electric field to digitally displace the shape memory ceramic element to turn on / off the electric contact. A relay device, which is capable of reversing the normal state and returning the electrical contacts to the normal state again at a predetermined temperature. 7. A ferroelectric shape memory ceramic that is digitally displaced by a phase transition from an antiferroelectric phase to a ferroelectric phase induced when a predetermined electric field is applied, and maintains the ferroelectric phase even after the electric field is cut off. A laminated body in which a plurality of elements are laminated, an insulating portion arranged on each side surface of the laminated body in a staggered manner on each side surface, and an insulating portion which is continuous in the laminating direction through the insulating portion. And a mover that moves according to the digital displacement of the laminated body to turn on and off electrical contacts, and applies a predetermined electric field to the metallic conductor portion to displace the laminated body in the laminating direction. A relay device capable of reversing an electric contact from a normal state of either on or off and returning the electric contact to a normal state again at a predetermined temperature.