JP2002237625A - Rolled piezoelectric element manufacturing apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rolled piezoelectric element manufacturing apparatus capable of efficiently winding up a piezoelectric ceramic laminate using a simple constitution. SOLUTION: The rolled piezoelectric element manufacturing apparatus for manufacturing a rolled piezoelectric element by rolling a laminate 36, composed of a thin plate-like piezoelectric material layer and an electrode layer into a tubular shape has a first member 14 and a second member 12, disposed with a prescribed spacing from the first member and relatively moving with respect to the first member. The second member 12 is moved, relative to the first member 14, to roll the laminate 36 being contacted to the first and second members into a tubular shape.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus and a method for manufacturing a roll-type piezoelectric element in which a laminate composed of a piezoelectric material layer made of a ceramic piezoelectric material and an electrode layer has a spiral structure.

[0002]

2. Description of the Related Art Conventionally, a roll-type piezoelectric element is formed by forming electrodes on a piezoelectric ceramic thin plate made by a doctor blade method or the like on one entire surface by printing or the like to form a laminate.
It is manufactured by stacking two laminates and winding them in a roll shape so that the electrode-formed surface of the first laminate faces the electrode non-formed surface of the second laminate, and firing the laminate at a predetermined temperature.

[0003] When winding the piezoelectric laminate, a method has been adopted in which the piezoelectric laminate is wound around a shaft made of a material which is burned out during firing, or a center axis is removed before firing.

[0004]

However, in the method of winding the ceramic sheet around the center axis and winding it while applying pressure, when winding a ceramic sheet elongated in the winding axis direction, the straightness of the center axis and the length of the center axis may be reduced. Variations in diameter occur, making it difficult to produce a uniform roll-type piezoelectric element. In the case of a manufacturing method in which the central axis is extracted before firing, it is difficult to extract the central axis from the elongated roll. Furthermore, when the element is downsized, the above point becomes more difficult because the diameter of the central axis is also reduced. Further, if the ceramic sheet is wound while being pressed at the stage of winding around the center axis, problems such as breakage or stretching of the ceramic sheet are likely to occur.

For the above reasons, the above method is not suitable for mass production.

Accordingly, a technical problem to be solved by the present invention is to provide a roll-type piezoelectric element manufacturing apparatus capable of efficiently winding a piezoelectric ceramic laminate with a simple configuration.

[0007]

The present invention provides a roll-type piezoelectric element manufacturing apparatus having the following configuration in order to solve the above technical problems.

The roll type piezoelectric element manufacturing apparatus is an apparatus for manufacturing a roll type piezoelectric element formed by winding a laminate composed of a thin plate-like piezoelectric material layer made of a ceramic piezoelectric material and an electrode layer into a cylindrical shape. is there. The roll-type piezoelectric element manufacturing apparatus includes a first member and a second member that is disposed at a predetermined distance from the first member and relatively moves with respect to the first member.
The laminate has a cylindrical shape while rotating while being in contact with the first member and the second member by relative movement of the second member with respect to the first member. Rolled up.

In the above structure, the laminated body is, for example,
An electrode layer is formed by kneading a powder of lead zirconate titanate (PZT) or the like with a binder resin or the like with a solvent and printing the surface of a ceramic piezoelectric material called a green sheet formed in a sheet shape. The laminated body manufactured in this way is put between the first and second members. The first and second members are relatively moving, and the loaded laminate comes into contact with both members and is conveyed while rolling in the gap in the radial direction. When the distance between the two members is gradually reduced as the laminate advances in the direction in which the laminate is being conveyed, the laminate that has been loosely wound first becomes gradually narrower and tighter while slipping between the layers, and has a predetermined diameter. .

According to the above structure, since the roll-type piezoelectric element can be manufactured at a low pressure, the load applied to the laminated body is small, and even if a thin laminated body is used, there is no breakage or deformation and a high yield rate can be achieved. It is possible.

Further, since the diameter of the roll-type piezoelectric element is determined by the distance between the first and second members, it is possible to produce a uniform roll-type piezoelectric element without causing variations in straightness and diameter of the central axis. Can be.

Further, since the winding shaft is not used for manufacturing the roll type piezoelectric element, it is not necessary to remove the winding shaft after winding. Therefore, it is possible to wind a large-sized laminate. After winding a large-sized laminate, the roll-type piezoelectric element can be mass-produced by cutting in the axial direction.

Therefore, the laminate of piezoelectric ceramics can be efficiently rolled with a simple configuration.

The piezoelectric conversion element of the present invention can be constructed in various modes as described below.

[0015] Preferably, the distance between the first member and the second member is wide on the entrance side where the laminate is introduced, and gradually narrows toward the exit.

In the above structure, since the laminate is wound by rolling between the gaps provided between the first member and the second member, the gap is gradually narrowed to thereby reduce the lamination. You can gradually tighten your body.

Preferably, the distance between the first member and the second member is variable.

According to the above configuration, for example, by adjusting the position of the second member and changing the interval provided between the first member and the second member, various types of roll-type piezoelectric members are provided. A device can be manufactured.

[0019] Preferably, a contact surface of at least one of the first and second members in contact with the laminate is substantially flat.

In the above structure, since the laminate is rolled up by rolling in contact with the first and second members, a contact surface with at least one of the first and second members is laminated. Is preferably a plane.

According to the above configuration, it is easy to control the interval between the second members with high precision, and it is possible to control the dimensions of the roll-type piezoelectric element with high precision.

[0022] Preferably, at least one of the first and second members is formed in an endless belt shape.

According to the above configuration, at least one of the first and second members is configured as a belt conveyer, and is continuously rotated, whereby a roll-type piezoelectric element can be manufactured continuously.

Preferably, a contact surface of at least one of the first and second members, which contacts the laminate, is a substantially cylindrical surface.

According to the above arrangement, the first and second cylindrical members are formed.
By rotating at least one of the members about the central axis, a roll-type piezoelectric element can be manufactured continuously.

Preferably, the apparatus for manufacturing a roll-type piezoelectric element further includes a device for loosely winding at least a part of the laminated body to be charged and for setting a winding habit in advance so as to have a larger diameter than the completed state.

According to the above configuration, at least a part of the laminate to be put into the roll-type piezoelectric element manufacturing apparatus is gently wound in advance so as to have a larger diameter than the completed state. At the time of taking, it becomes easy to take up well.

Preferably, a contact surface of the first and second members which comes into contact with the laminate has a coefficient of static friction of 0.3 or more.

In the above structure, the contact surface of the first and second members with the laminate preferably has a friction coefficient that does not cause slippage when the laminate is wound, and a static friction coefficient of 0.3 or more. Then, this condition is satisfied.

Further, the present invention provides the following method for manufacturing a roll-type piezoelectric element.

In a method of manufacturing a roll-type piezoelectric element, an adhesive is applied to a contact surface of at least one of the first member and the second member, which is in contact with the laminate, using the above-described roll-type piezoelectric element manufacturing apparatus. The adhesive is applied and transferred while transferring the adhesive to the laminate when the laminate is wound into a cylindrical shape.

When an adhesive is applied to at least one contact surface of the first member and the second member, the laminate is rotated with the relative movement of the second member with respect to the first member, and the adhesive is applied to the outer periphery. Is applied. Thereafter, since the diameter of the laminate gradually decreases while causing slippage between the layers, the adhesive applied to the outer periphery is wound between the layers, and the winding end is bonded.

According to the above method, when manufacturing a roll-type piezoelectric element, the end of winding can be bonded, so that the wound laminate does not loosen again. Therefore, the piezoelectric ceramic laminate can be efficiently rolled.

[0034]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a roll type piezoelectric element manufacturing apparatus according to each embodiment of the present invention will be described with reference to the drawings.

FIG. 1 shows a roll type piezoelectric element manufacturing apparatus according to a first embodiment of the present invention. In order to manufacture a roll-type piezoelectric device by the roll-type piezoelectric element manufacturing apparatus of the present embodiment, first, a preliminary winding step is performed. The preliminary winding step is a step of winding the laminate looser than a predetermined shape to form a winding habit. In the device shown in FIG. 1A, a groove 35 having a semicircular cross section is provided in a central portion of a main body 34.
In the preliminary winding step, the laminated body 30 in which electrodes are printed on green sheets of piezoelectric ceramics is arranged on the apparatus main body 34, and a part of the laminated body 30 existing on the groove 35 extends in the axial direction of the winding shaft 32. Sandwich it. In this state,
By rotating the winding shaft 32 in the direction of the arrow 50, the laminate 30 is wound into a circular shape more loosely than a predetermined shape along the shape of the groove having a semicircular cross-section, and a processed laminate having a winding habit. 36 are made.

As shown in FIG. 1 (b), the processed laminated body 36 having the curl is wound loosely, and the diameter thereof is made larger than the diameter of the roll type laminated body which is a finished product.

The rolled processing laminate 36 is put into a roll type piezoelectric element manufacturing apparatus shown in FIG. The roll type piezoelectric element manufacturing apparatus 10 has a belt conveyor 12 and a winding plate 14. Winding plate 14
Is fixed at a predetermined distance with respect to the belt conveyor 12, and is wide on the input port side as shown in FIG.
It gradually becomes narrower in the transport direction.

In the preliminary winding step, the processed laminated body 36 having a winding habit is introduced into the inlet 16. The loaded processed laminate 36 falls onto the belt conveyor 12. The belt conveyor 12 is rotating in the direction shown by the arrow 52,
The processing laminate 36 is transported. Processed stacked body 36 transported
a is in contact with both the belt conveyor 12 and the take-up plate 14 and rolls a gradually narrowing space as shown by 36b in the direction shown by the arrow 54, thereby forming a space 2 between the wound layers.
It is thinly wound while sliding at 1, 22, 23 and 24.

By appropriately adjusting the distance 15 between the belt conveyor 12 and the winding plate 14 at the outlet, a roll-type piezoelectric element 36c having a desired diameter can be manufactured.

An example of adjusting the interval between the outlets will be described below. When the thickness of the laminate is 100 μm and the length in the winding direction is 50 mm, the cross-sectional area when the winding is smallest is 5 m.
m ² and the diameter is about 2.52 mm. When the interval between the outlets is adjusted to 2.52 mm, the laminate is sufficiently wound and tightened, and a roll-type piezoelectric element 36 ′ having no center gap as shown in FIG. 3A can be obtained. When the interval between the outlets is set to 3 mm, a roll-type piezoelectric element 36 '' having an outer diameter of 3 mm and having a gap 40 at the winding center as shown in FIG. 3B is obtained.

FIG. 4 is a diagram showing another example of the configuration of the apparatus for performing the preliminary winding step. The device shown in FIG.
The main body 34a is composed of two plates 38a and 38b, and each plate is connected by a hinge 37. One board 3
8b is provided with a groove 35 having a semicircular cross section at its end. In the preliminary winding step, the laminated body 30 in which electrodes are printed on a green sheet of piezoelectric ceramic is
a, 38b along the surface thereof. In this state, the plate 38b is folded as shown by the arrow 56. The state at this time is shown in FIG. As shown in FIG.
The plate 38b passes through a state 38b 'shown by a broken line,
Rotating about the hinge as shown at 6, the plate 3
It is folded so as to overlap with 8a. As shown in FIG. 4C, the laminate 30 at this time is embossed along the groove of the plate 38b, and is folded while the folded portion 30 'is expanded.

The pre-process apparatus is suitable for manufacturing a roll-type piezoelectric element in which electrodes are formed on both surfaces of the laminate 30 and wound from the center. In this type of roll-type piezoelectric element, a laminate in which electrodes are applied to both surfaces of a green sheet of piezoelectric ceramic is used. Even if there is a gap between the wound layers, the effective area of the electrode does not change, so that it is not necessary to apply a high pressure to bring the layers into close contact. According to this processed laminated body, by appropriately adjusting the interval 15 between the belt conveyor 12 and the winding plate 14, a roll-type piezoelectric element in which the layers are closely contacted as shown in FIG.
It is also possible to cope with a roll-type piezoelectric element having a winding 40 having a gap 40 between layers or at the center of winding as shown in FIG. Therefore, according to this apparatus, since the diameter can be arbitrarily controlled, the outer diameter of the roll-type piezoelectric element is determined by the thickness, length, and thickness of the winding shaft of the laminate, and fine adjustment is difficult. The problem can be solved. Also,
Since the roll-type piezoelectric element can be manufactured at a low pressure, the load applied to the laminated body is small, and even when a thin laminated body is manufactured, there is little breakage or deformation, and it is possible to manufacture at a high yield rate. Furthermore, since a winding shaft is not used, a large-sized laminate can be wound.

FIG. 5 shows the configuration of a roll type piezoelectric element manufacturing apparatus according to a second embodiment of the present invention. As schematically shown in FIG. 5, the roll-type piezoelectric element manufacturing apparatus of the present embodiment includes an upper winding plate 14 'and a lower winding plate 12'. The upper take-up plate 14 ′ is different from the lower take-up plate
It is installed with a gradually narrowing gap. The upper take-up plate 14 'performs a parallel movement along a locus shown by an arrow 56, and rotates and moves as shown by 14'a and 14'b. When the processed laminated body after the preliminary winding step is supplied from the input port, the processed laminated body 36 contacts the upper winding plate 14 'and the lower winding plate 12', and
It moves with the movement of 4 'and is wound up to a predetermined diameter until it is separated from the rear end of the upper winding plate as shown by 36e. The fact that the completed diameter of the roll-type piezoelectric element 36e is determined by the exit distance 15 is the same as in the above-described first embodiment.

The apparatus for manufacturing a roll-type piezoelectric element according to this embodiment is suitable for manufacturing a roll-type piezoelectric element in which the layers are brought into close contact with each other at high pressure.

In a roll-type piezoelectric element manufactured by stacking and winding two laminates each having an electrode provided on one side of a ceramic sheet, when a gap is formed between the winding layers, the portion becomes positive and negative electrodes. It is a defective part that is not pinched. For this reason, it is necessary to take up the laminate while applying pressure so that the layers are in close contact with each other.

For this purpose, the surface with which the processed laminated body 36 contacts needs to have high flatness and high rigidity. According to the second embodiment, the upper winding plate 1
The 4 'and the lower winding plate 12' can be made of metal or the like, and can have high flatness and high rigidity.

FIG. 6 shows the configuration of a roll-type piezoelectric element manufacturing apparatus according to a third embodiment of the present invention. As shown schematically in FIG. 6, the roll-type piezoelectric element manufacturing apparatus according to the present embodiment includes a fixed-side winding cylinder 12c and a movable-side winding cylinder 14c.
And The movable-side take-up cylinder 14c is provided so as to rotate in the direction indicated by the arrow 58 with respect to the fixed-side take-up cylinder 12c, and the distance between the surface thereof and the surface of the fixed-side take-up cylinder 12c gradually decreases. It is installed in. When the processed laminated body 36 after the preliminary winding step is introduced from the input port, the processed laminated body 36 enters a gap between the two cylinders as indicated by an arrow 60, and is wound into a rolling roll while being in contact with the surfaces of the two cylinders. Tightened. The finished diameter of the processed laminate 36f rolled to the outlet is determined by the distance between the two cylinders at the outlet, and is discharged out of the apparatus as indicated by an arrow 62.

FIG. 7 shows the configuration of a roll-type piezoelectric element manufacturing apparatus according to a fourth embodiment of the present invention. The roll-type piezoelectric element manufacturing apparatus of the present embodiment includes a belt conveyor 12 and a winding plate 14, as schematically shown in FIG. The take-up plate 14 is not narrowed gradually from the inlet to the outlet, and is provided substantially parallel to the belt conveyor 12. Further, as shown in the drawing, the winding plate 14 can change the interval between the winding plate 14 and the belt conveyor 12.
It is provided so that the position can be changed between 14d indicated by the broken line. A predetermined load F is applied to the winding plate 14 by an arrow 7.
As shown by "0", it is set in the direction of the belt conveyor 12. The belt conveyor 12 rotates in a direction indicated by an arrow 66, and conveys the processed laminated body 36 input from the input port. When the processed laminated body 36 comes into contact with the winding plate 14, it rolls in the direction indicated by the arrow 64 with the movement of the belt conveyor 12, and is thinly tightened while causing slippage between the wound layers. Since the position of the take-up plate 14 is variable and a load is applied downward, the processed laminate 36 is strongly wound. That is,
By controlling the load F, the winding pressure can be adjusted, and the roll-type piezoelectric element 36g can be manufactured more favorably.

As a modified example of the roll type piezoelectric element manufacturing apparatus of the present invention, an example in which an adhesive is applied after winding the processed laminated body to prevent the end of the winding end from being loosened will be described. Although there is no particular limitation on the type of the manufacturing apparatus, an example of the manufacturing apparatus will be described with reference to the first embodiment shown in FIG.

In the apparatus for manufacturing a roll-type piezoelectric element shown in FIG. 2, an adhesive liquid supply section is provided on the belt conveyor 12 so that an appropriate amount of adhesive liquid can be supplied by means such as application or spraying. As described above, the processed laminated body 36 comes into contact with both the belt conveyor 12 and the winding plate 14 and is wound on the belt conveyor 12 while relatively rolling backward in the traveling direction. When the adhesive liquid supply unit is disposed behind the charging position, the adhesive liquid is applied to the outer periphery of the processed laminate 36. Thereafter, since the diameter of the processed laminate 36 gradually decreases while causing slippage between the layers, the adhesive applied to the outer periphery is also involved in the layers, and the winding end is bonded.

The adhesive liquid to be applied is preferably one that will be burned off during the firing process. Specifically, in the above example, a rubber-based adhesive is used, but a urethane-based or other organic-based adhesive can also be used. In addition, not only a liquid but also an adhesive material that is burned off in a firing step, such as a powdery adhesive that adheres under pressure or temperature, can be used.

In addition, as a means for maintaining the winding shape, a tape which is burned off in the firing step may be wound or clipped. It is also possible to utilize the self-tack property of the laminate or perform pressure bonding.

As another example, the laminate may be inserted into a tube made of ceramic or the like which does not cause firing or deformation at the firing temperature and fired. Since the wound laminate shrinks when fired, it can be easily removed from the tube.

In each of the above embodiments, the contact surface of the two members with which the processed laminate comes into contact preferably has a coefficient of friction that does not cause slippage when winding the laminate. Specifically, it is desirable that the coefficient of static friction is 0.3 or more. To adjust the coefficient of static friction, rubber, silicon, etc. may be provided on the contact surface, blasting, electrolytic corrosion,
The surface may be made uneven by means such as embossing.

In addition to the roll-type piezoelectric element manufacturing apparatus shown in the above-described embodiment, the same applies to a combination of a cylinder and a plane, or an elliptical or long cylinder whose winding surface is appropriately curved. A roll type piezoelectric element can be manufactured. For example, as shown in FIG. 8 showing the fourth embodiment,
By appropriately changing the interval between the take-up plate 14 and the belt conveyor 12 in the transport direction 68, the laminated body that has been once firmly tightened at the central portion 14x of the take-up plate moves to the rear portion 14y. The roll-type piezoelectric element 3 which is slightly loosened as a whole and is wound in a shape having a gap between layers.
It is also possible to produce 6h.

It should be noted that the present invention is not limited to the above embodiment, but can be implemented in various other modes.

[Brief description of the drawings]

FIG. 1 is a view showing a roll-type piezoelectric element manufacturing apparatus according to a first embodiment of the present invention.

FIG. 2 is a view for explaining the principle of the roll-type piezoelectric element manufacturing apparatus according to the first embodiment of the present invention.

FIG. 3 is a diagram illustrating an example of a roll-type piezoelectric element manufactured by the roll-type piezoelectric element manufacturing apparatus according to the first embodiment of the present invention.

FIG. 4 is a diagram showing another configuration example of an apparatus for performing a preliminary winding step.

FIG. 5 is a view showing a roll-type piezoelectric element manufacturing apparatus according to a second embodiment of the present invention.

FIG. 6 is a view showing a roll-type piezoelectric element manufacturing apparatus according to a third embodiment of the present invention.

FIG. 7 is a view showing a roll-type piezoelectric element manufacturing apparatus according to a fourth embodiment of the present invention.

FIG. 8 is a view showing a modification of the roll-type piezoelectric element manufacturing apparatus of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Roll-type piezoelectric element manufacturing apparatus 12 Belt conveyor 12 'Lower take-up plate 12c Fixed-side take-up cylinder 14 Take-up plate 14' Upper take-up plate 14c Movable-side take-up cylinder 16 Input port 30 Laminated body 30 'Folding part 32 Winding Take-up shaft 34, 34a Pre-winding device main body 35 Groove 36 Worked laminate 36 ', 36' 'Roll type piezoelectric element 37 Hinge 38a, 38b Plate 40 Air gap

Claims (9)

[Claims] 1. A roll-type piezoelectric element manufacturing apparatus for manufacturing a roll-type piezoelectric element formed by winding a laminate comprising a thin plate-like piezoelectric material layer made of a ceramic-based piezoelectric material and an electrode layer into a cylindrical shape, A first member, and a second member disposed at a predetermined distance from the first member and relatively moving with respect to the first member, wherein the second member with respect to the first member An apparatus for manufacturing a roll-type piezoelectric element, wherein a relative movement of a member causes the laminate to be wound into a cylindrical shape while rotating while being in contact with the first member and the second member. 2. The distance between the first member and the second member is wide at an entrance side where the laminate is introduced, and gradually narrows toward an exit direction. 2. The roll-type piezoelectric element manufacturing apparatus according to 1. 3. The roll-type piezoelectric device manufacturing apparatus according to claim 1, wherein a distance between the first member and the second member is variable. 4. The roll-type piezoelectric element manufacturing apparatus according to claim 1, wherein a contact surface of at least one of the first and second members that contacts the laminated body is substantially flat. 5. The roll-type piezoelectric element manufacturing apparatus according to claim 3, wherein at least one of the first and second members is formed in an endless belt shape. 6. The roll-type piezoelectric element manufacturing apparatus according to claim 1, wherein a contact surface of at least one of the first and second members that contacts the laminate is a substantially cylindrical surface. 7. The apparatus further comprises a device for loosely winding at least a part of the laminated body to be charged, and for setting a winding habit in advance so as to have a larger diameter than a completed state.
The roll-type piezoelectric element manufacturing apparatus according to claim 1. 8. The device according to claim 1, wherein a contact surface of the first and second members that contacts the laminate has a static friction coefficient of 0.3 or more. Roll type piezoelectric element manufacturing equipment. 9. A method for manufacturing a roll-type piezoelectric element using the roll-type piezoelectric element manufacturing apparatus according to claim 1, wherein the roll-type piezoelectric element is in contact with the laminate of at least one of the first member and the second member. A method of manufacturing a roll-type piezoelectric element, comprising applying an adhesive to a contact surface and winding the laminate while transferring the adhesive to the laminate when the laminate is wound into a cylindrical shape.