Device for magnifying displacement of piezoelectric element or the like and method for producing same
| Title: | Device for magnifying displacement of piezoelectric element or the like and method for producing same |
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| Patent Number: | 4,979,275 |
| Publication Date: | December 25, 1990 |
| Appl. No: | 07/397,751 |
| Application Filed: | August 23, 1989 |
| Abstract: | A method of producing a device for magnifying displacement of a piezoelectric element adapted to be displaced by application of voltage thereto. The method includes a first step of forming a movable member integrally with a frame through a connecting portion in such a manner as a space for inserting therein a piezoelectric element is defined between the movable member and a base portion of the frame; a second step of fixing the leaf spring to the frame and the movable member; and a third step of forming a separation groove in the connecting portion to separate the movable member from the frame. |
| Inventors: | Sakaida, Atsuo (Gifu, JPX); Ikezaki, Yoshiyuki (Nagoya, JPX); Iriguchi, Akira (Nagoya, JPX); Chikaoka, Yasuji (Aichi, JPX); Imoto, Yasuo (Nagoya, JPX) |
| Assignees: | Brother Kogyo Kabushiki Kaisha (Aichi, JPX) |
| Claim: | What is claimed is |
| Claim: | 1. A method of producing a device for magnifying displacement of a piezoelectric element adapted to be displaced by application of voltage thereto, said device comprising |
| Claim: | a frame extending substantially parallel to a direction of displacement of said piezoelectric element; |
| Claim: | a movable member fixed to one end of said piezoelectric element with respect to the direction of displacement; |
| Claim: | a first mount surface formed on said frame and extending substantially parallel to the direction of displacement; |
| Claim: | a second mount surface formed on said movable member and extending substantially parallel to the direction of displacement, said second mount surface being opposed to said first mount surface; |
| Claim: | a first leaf spring mounted at one end portion thereof on said first mount surface and extending substantially parallel to the direction of displacement; |
| Claim: | a second leaf spring mounted at its one end portion on said second mount surface and extending substantially parallel to the direction of displacement; and |
| Claim: | a rolling member fixed to other end portions of said first and second leaf springs, wherein when said piezoelectric element is displaced, said second leaf spring is displaced relative to said first leaf spring through said movable member to roll said rolling member, said method comprising |
| Claim: | a first step of forming said movable member integrally with said frame through a connecting portion to define a space for inserting therein said piezoelectric element between said movable member and a base portion of said frame; |
| Claim: | a second step of fixing said first and second leaf springs to said frame and said movable member; and |
| Claim: | a third step of forming a separation groove in said connecting portion to separate said movable member from said frame. |
| Claim: | 2. The method as defined in claim 1, wherein said second step includes fixing said rolling member to said leaf springs. |
| Claim: | 3. The method as defined in claim 1, wherein said second step includes fixing said leaf springs formed independently of each other to said frame and said movable member. |
| Claim: | 4. The method as defined in claim 1, wherein said second step includes fixing a single spring member to said frame and said movable member, and said third step includes forming a split groove extending from an end of said spring member on said connecting portion side toward said rolling member to thereby form said first and second leaf springs. |
| Claim: | 5. A method of producing a device for magnifying displacement of an elongated piezoelectric element adapted to be displaced by application of voltage thereto, comprising |
| Claim: | a first step of forming an integral frame body having a main frame extending along one side of said piezoelectric element, a supporting portion for supporting one end of said piezoelectric element with respect to a direction of displacement of said piezoelectric element, a movable member mounted on the other end of said piezoelectric element with respect to the direction of displacement of said piezoelectric element, and a sub frame extending along the other side of said piezoelectric element opposite to said main frame; |
| Claim: | a second step of fixing a pair of leaf springs connected at one end with a rocking member to said main frame and said movable member; |
| Claim: | a third step of forming a first parting slit between said main frame and said movable member and a second parting slit between said movable member and said sub frame to separate said main frame, said movable member and said sub frame; |
| Claim: | a fourth step of fixing a quadri-hinged parallel link mechanism between said movable member and said sub frame; and |
| Claim: | a fifth step of fixing said piezoelectric element between said supporting portion and said movable member. |
| Claim: | 6. The method as defined in claim 5, wherein said first step comprises injection-molding a mixture of metal powder and resin, heating a molding obtained above at a predetermined temperature, and sintering the molding at a predetermined temperature in an atmospheric gas. |
| Claim: | 7. The method as defined in claim 5, wherein said first step includes formation of a recess for inserting the other end of said leaf springs. |
| Claim: | 8. The method as defined in claim 5, wherein said first step includes formation of thin-walled portions of said movable member and said sub frame at a position where said quadri-hinged parallel link mechanism is fixed. |
| Claim: | 9. The method as defined in claim 5 further comprising a step of integrally forming said leaf springs with said rocking member. |
| Claim: | 10. The method as defined in claim 9 further comprising a step of fixing said rocking member to one end of a rocking arm and fixing the other end of said rocking arm to a printing wire. |
| Claim: | 11. The method as defined in claim 5, wherein said leaf springs are brazed to said main frame and said movable member. |
| Claim: | 12. The method as defined in claim 5, wherein said quadri-hinged parallel link mechanism is welded to said movable member and said sub frame. |
| Claim: | 13. The method as defined in claim 5, wherein said first and second parting slits are formed by laser cutting or wire-cut electrical discharge cutting. |
| Claim: | 14. The method as defined in claim 5, wherein said quadri-hinged parallel link mechanism comprises a pair of opposed parallel link plates and a bridge portion integrally connecting said parallel link plates, and said fourth step further comprising a step of mounting said parallel link plates on opposite side surfaces of said movable member and opposite side surfaces of said sub frame and a step of positioning said parallel link plates. |
| Claim: | 15. The method as defined in claim 5 further comprising a step of interposing between said supporting portion and said piezoelectric element a preload member for applying a given compression load to said piezoelectric element in a rest position of said piezoelectric element and a temperature compensating member having a characteristic of temperature-linear expansion contrary to that of said piezoelectric element. |
| Claim: | 16. The method as defined in claim 15, wherein said preload member has an inverted U-shaped configuration composed of an upper plate portion and a pair of side plate portions, and said interposing step comprises fixing said temperature compensating member to one end of said piezoelectric element, movably mounting said preload member on said supporting portion, and fixing said side plate portions of said preload member to opposite side surfaces of said supporting portion. |
| Claim: | 17. The method as defined in claim 6, wherein said meal powder is an alloy powder containing about 31 wt % or more of Ni, about 5 wt % or more of Co, and a residual quantity of Fe. |
| Current U.S. Class: | 29/2535; 29/416; 29/418; 310/328 |
| Current International Class: | H01L 4122 |
| Patent References Cited: | 3460244 August 1969 Metz 3524196 August 1970 Church et al. 3614486 October 1971 Smiley 3624896 December 1971 Danbeney et al. 3649857 March 1972 Knappe 3955049 May 1976 MacNeil et al. 4435666 March 1984 Fukui et al. 4518887 May 1985 Yano et al. 4547086 October 1985 Matsumoto et al. 4570095 February 1986 Uchikawa 4589786 May 1986 Fukui et al. 4672257 June 1987 Oota et al. 4675568 June 1987 Uchikawa et al. |
| Primary Examiner: | Hall, Carl E. |
| Attorney, Agent or Firm: | Oliff & Berridge |
| Accession Number: | edspgr.04979275 |
| Database: | USPTO Patent Grants |
| Language: | English |
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