Patent Translate Powered by EPO and Google Notice This translation is machine-generated. It cannot be guaranteed that it is intelligible, accurate, complete, reliable or fit for specific purposes. Critical decisions, such as commercially relevant or financial decisions, should not be based on machine-translation output. DESCRIPTION JPH03254952 [0001] [Industrial Application Field] The present invention relates to a printing element, in particular, a printing element in which the dimensional distortion generated by the piezoelectric or electrostrictive longitudinal effect of the piezoelectric ceramic material is enlarged and transmitted to the printing wire for dot printing . [Prior Art] Conventionally, as such a printing element, there is, for example, one as shown in FIG. In this printing element, the drive source 1 consisting of laminated longitudinal effect piezoelectric elements that expand and contract by the application of voltage is attached to a frame (main frame 2) having a base 3 supporting one end of the drive source 1 in the expansion and contraction direction There is. A mover 5 disposed at the other end of the drive source 1 in the expansion / contraction direction is attached, and is connected to the mover 5 to have a motion conversion mechanism for expanding the expansion / contraction motion of the drive source 1. This motion conversion mechanism mainly includes a pair of leaf springs 6.7 having one end fixed to the main frame 2 and the mover 5, and a tilting body 8 connecting the other ends of the leaf springs 6.7. ing. The motion conversion mechanism converts the expansion and contraction movement of the drive source 1 due to the application of the voltage and the interruption of the voltage into the tilting movement of the tilting body 8 using the deflection of the plate spring 6.7. In accordance with this tilting movement, the wire 11 impacts in the two directions shown in FIG. In the printing element as described above, as shown in FIG. 4, for example, the thickness of the − layer is 98 μm and the piezoelectric constant aaS is 6, 35 × 10 −10 m / V as the driving source 1 The piezoelectric ceramic layer 42 having a constant M33 of 1,32 × 10 golo m / v 2 is stacked 180 layers via the electrode layer 41 having a thickness of 2 μm, and the total length is 18 mm. . Therefore, in order to obtain the displacement of the drive source 1 necessary for printing, for example, 15 μm, a drive voltage of 107 V is required. In the drawing, the arrow 45 indicates the polarization direction of the piezoelectric ceramic layer 41. In addition, the drive source 1 has a property that the strain 04-05-2019 1 accompanying polarization is released at the time of temperature rise, and therefore, unlike other components, it has a negative linear expansion coefficient (for example, -3 s ppm / ° C) in the stretching direction. Have. For this reason, the main frame 2 and the drive source 1 due to the / + 111 degrees one rise in operation. It is necessary to correct the difference in the amount of expansion of Therefore, a low expansion coefficient component (for example, an invar alloy with a linear expansion coefficient of +1.2 ppm / 'C) is used as the material of the main frame 2, and a rigid body having a large positive linear expansion coefficient as the temperature compensation material 12.13. (For example, aluminum having a linear expansion coefficient of +23.9 ppm / ° C. and a total length of 4 mm) was used. [Problem to be solved by the invention] However, there is a problem that the device described in 1 requires a high drive voltage (107 V on the upper side). In order to reduce this drive voltage, for example, it is easily considered to reduce the thickness of one layer of the piezoelectric ceramic layer 42 and to increase the number of stacked layers. However, such a multilayer device has a new problem that the reliability is lowered due to the temperature difference between the layer in the vicinity of the surface and the layer in the central portion during sintering, and the number of laminated layers can not be increased so much. In addition, since the low expansion coefficient component in the above-described apparatus is very expensive, there is a problem that the material cost is high. When the thermal conductivity of the drive source 1 is not sufficiently large, a temperature difference occurs between the drive source 1 and the temperature compensation member 12.13 during driving. For this reason, the dual temperature compensation effect is not obtained sufficiently, and the thermal expansion of the drive source 1 precedes, and the tip position of the wire 11 protrudes more than before the temperature rise. Therefore, there is also a problem that the end of the wire 11 is likely to cause a defect such as being caught by the ink ribbon. The present invention has been made to solve the above-mentioned problems, and provides a driving source comprising a laminated longitudinal effect piezoelectric element in which the thickness of one layer of the piezoelectric ceramic layer is reduced without reducing the reliability. With the goal. Furthermore, it aims at reducing the drive voltage of an element. Furthermore, the linear expansion coefficient of the drive source is controlled by changing the ratio of the length of the temperature compensation material to the laminated piezoelectric element, and the freedom of selection of the mainframe material is increased, thereby reducing the cost of the mainframe material. The purpose is Furthermore, it is an object of the present invention to reduce the temperature difference during driving between the driving source and the temperature compensation member as compared with the prior art, to improve the reliability of the temperature compensation effect, and to provide a low cost and highly reliable printing element. . [Means for Solving the Problems] In order to achieve the above object, the present invention provides a drive source that generates a piezoelectric longitudinal effect or an electrostrictive longitudinal effect by the application of an electric signal, and one end of the drive source in the stretching direction. A printing element provided with a frame having a base for supporting the movement and a motion conversion 04-05-2019 2 mechanism for expanding the expansion and contraction movement of the drive source, wherein the drive source comprises a plurality of laminated longitudinal effect electric machines configured by laminating piezoelectric ceramic layers A conversion element and a plurality of temperature compensation members for correcting the linear expansion coefficient of the laminated longitudinal effect electromechanical conversion element to make the linear expansion coefficient as the entire drive source identical to that of the frame are alternately arranged. It is characterized by becoming. [Operation] According to the present invention having the abovedescribed configuration, by laminating the required number of laminated longitudinal effect electro-mechanical transducers, − = 6̶a desired displacement amount can be obtained. The number of laminated conversion elements may be small. Therefore, temperature differences hardly occur at the center and the periphery during sintering. Therefore, even if the thickness of the layer is, for example, about 40 μm, it can be obtained while maintaining high reliability. In addition, since each stacked vertical effect electromechanical transducer is formed by stacking thin piezoelectric elements or electrostrictive elements, a large displacement can be obtained with a small voltage. Furthermore, since it is possible to shorten the length of the laminated longitudinal effect electromechanical transducer necessary to obtain an appropriate displacement, it is possible to lengthen the length of the temperature compensation material occupied in the drive source accordingly. Therefore, it becomes possible to use an inexpensive material for the frame. The linear expansion coefficient of the drive source can be freely adjusted in accordance with the linear expansion coefficient of the main frame material, and cost reduction of the main frame material can be realized. Further, by alternately arranging a plurality of laminated piezoelectric elements and a plurality of temperature compensation materials, heat generated by the elements is efficiently transmitted to the temperature compensation material. Therefore, the temperature difference at the time of driving between the laminated longitudinal effect electromechanical transducer and the temperature compensation material can be made smaller than that in the prior art. Therefore, an appropriate temperature compensation effect can be obtained. Embodiment An embodiment of the present invention will be described with reference to FIGS. 1 and 2. FIG. For convenience, the same parts as or parts equivalent to those of the conventional example are designated by the same reference numerals and the detailed description thereof is omitted. As shown in FIG. 1, the frame 80 supporting the driving source 1 is a substantially U-shaped sintered steel material having a coefficient of linear expansion of +12.1 ppm / 'C. The frame 80 has a main frame portion 2 extending parallel to the expansion and contraction direction of the drive source 1, and a lower end portion of the main frame portion 2 supports one end (lower end) of the expansion and contraction direction of the drive source 1 Three are protruding. A subframe portion 4 is formed in parallel to the main frame portion 2 so as to be connected to the base portion 3. The mover 5 is disposed at the other end (upper side in the first illustration) of the drive source 1 in the expansion / contraction direction so as to face one end portion of the main frame portion 2. A pair of plate springs 6.7 are fixed to the opposing surfaces of the main frame portion 2 and the 04-05-2019 3 mover 5 at their one end. The two leaf springs 6.7 are opposed to each other with a predetermined gap, and the other end (extending end) is connected by the tilting body 8. A tilting arm 10 having a printing wire 11 attached at its tip is fixed to the two surfaces of the tilting body 8. Note that, by displacing the other end of one plate spring 7 along the surface direction of the plate spring 6 with the plate spring 6.7 and the tilting body 8, the tilting body 8 is made to move to tilt. The facing surfaces of the drive source 1 and the base 3 of the frame 80 and the facing surfaces of the drive source 1 and the mover 5 are bonded by an adhesive. Further, between the upper end portion of the sub-frame portion 4 and the mover 5, the mover 5 is moved in parallel with the extension direction of the drive source 1 based on the extension of the drive source 1. 16 are provided. In the printing element described above, when a voltage is applied to the drive source 1, the drive source 1 expands, and based on this, the mover 5 is displaced (raised). At this time, the tilting arm 10 is tilted in the counterclockwise direction in FIG. 1 by the deflection of the leaf spring 6 and the leaf spring 7 under the displacement force of the mover 5. The tilting of the tilting arm 10 advances the printing wire 11 to the printing position. When the application of the voltage to the drive source 1 is cut off, the drive source 1 is shortened to the original state. Based on this, when the mover 5, the plate spring 6 and the plate spring 7 are returned to the original state, the printing wire 11 is returned to the standby position. At this time, the tilting arm 10 abuts on the stopper 35 and is supported at the standby position. Further, the parallel link mechanism 16 is elastically deformed based on the displacement of the movable element 5, whereby the movable element 5 is displaced in parallel with the expansion and contraction direction of the drive source 1. The drive source 1 is composed of a laminated piezoelectric element 40 and a temperature compensation material 12 as shown in FIG. -The thickness of the layer is 40 μm, and the piezoelectric constant (Iaa is 6. A piezoelectric ceramic layer 42 with 35 × 10 −10 m / V and an electrostriction constant Ma 3 of 1.32 × 10 9 − ′ ′ m / V 2 is stacked in 45 sheets via an electrode layer 41 with a thickness of −2 μm. Then, the number of laminated layers is simplified as three sheets) and integrally sintered with a length of 1.89 mm to obtain the laminated piezoelectric element 40. The laminated piezoelectric element 40 configured as described above has a piezoelectric longitudinal effect. Further, as the temperature compensation material 12, aluminum of 3 ° 15 mm in length is used. Then, the temperature compensation members 12 are alternately stacked on five 1 stacked piezoelectric elements 40 and four − , and are bonded with a known adhesive to make the drive source 1 of this embodiment. The drive source 1 has a length of 22 mm, and expands and contracts in the longitudinal direction (the downward direction in FIG. 2) by the application of a voltage and the interruption of the application. The linear expansion coefficient of the laminated piezoelectric element 40 used for the driving source 1 is −3, 8 ppm 10 C due to the effect of release at the time of temperature rise of strain accompanying the polarization of the element. However, the temperature compensation material 12 made of aluminum has a large positive linear expansion coefficient +23. Since it has 9 p pm / 'C, the linear expansion coefficient for the entire length of 04-05-2019 4 the drive source 1 is substantially +12. It is 1 p pm / 'C. This value is the same as the linear expansion coefficient of the frame 80. In the above embodiment, with the drive voltage of 76 V, the displacement of the drive source 1 of 15 μm necessary for printing could be obtained. Therefore, the drive voltage is greatly reduced as compared with the conventional device which required 107 V as the drive voltage. . In the laminated piezoelectric element 40, although the thickness of one layer of the piezoelectric ceramic layer 42 is extremely thin at 40 μm, the number of laminated layers is as small as 45 and the length is as small as 1.89 mm. Control of uniformity and densification, etc. is easy, and there is no decrease in reliability with respect to piezoelectric characteristics, insulation characteristics and the like. Therefore, stable performance can be maintained as compared with the conventional device, and the yield of the drive source 1 is also improved. Further, as the electromechanical transducer of the drive source 1 is used as described above, the low voltage driven laminated type is used, therefore, sufficient displacement can be obtained even if the length of the device with respect to the entire length is shortened. . Therefore, it is easy to increase the ratio of the length occupied by the temperature compensation vJ12, and a high linear expansion coefficient of the drive source 1 can be obtained. Therefore, for example, as described above, the linear expansion coefficient is +12. By setting to 1 ppm / 'C, a relatively inexpensive sintered steel material can be used as a frame. In addition, by changing the ratio of the length of the temperature compensation member 12 to the total length, the linear expansion coefficient of the entire drive source can be adjusted, and a frame made of another material can be used. Further, in the present embodiment, the temperature difference between the driving source 1 and the temperature compensating member 12 caused by the heat generation from the driving source during the printing operation is significantly smaller than that in the conventional example. For example, in the experimental example, the temperature difference between the central portion of the drive source 1 and the temperature compensation material 12 is around 25 ° C. In the case where the present embodiment is applied to this, the laminated piezoelectric element 40 and the temperature compensation material 12 The temperature difference with is about 2 ° C. As a result, the reliability of the effect of temperature compensation is enhanced, and the occurrence of a defect such as the tip of the conventional wire 11 being caught on the ink ribbon can be prevented. Furthermore, the present invention is not limited to the abovedescribed embodiment, and modifications can be made according to applications without departing from the scope of the present invention. For example, when aiming to reduce the driving voltage without considering the cost reduction of the main frame 2, the piezoelectric ceramic layer 42 having a thickness of 40 μm is used as the driving source 1, and the thickness of the layer is 2 μm. Integrally-sintered laminated piezoelectric element 40 (the same as in the previous example) with the integral piezoelectric longitudinal effect laminated on 86 sheets via the electrode layer 41 and having a length of 3.61 mm The driving voltage required for printing can be reduced to 45 V by using the temperature compensating material 12 and four aluminum pieces of 1 mm in length arranged and joined with an adhesive and having a length of 22 mm. 04-05-2019 5 Furthermore, as the driving source 1 for low voltage driving, a piezoelectric ceramic layer 42 having a thickness of -20 μm is stacked on 164 sheets of an electrode layer 41 having a thickness of -2 μm, and the length is 3.61 mm. 5 stacked piezoelectric elements 40 (the piezoelectric constant and the electrostriction constant are the same as in the previous embodiment) of the piezoelectric longitudinal effect of integral sintering and 4 pieces of aluminum having a length of 1 mm as the temperature compensation material 12 The drive voltage required for printing can be reduced to 23 V by using an adhesive having a length of 22 mm. [Effects of the Invention] As is apparent from the detailed description in detail, according to the printing element of the present invention, a laminated longitudinal effect piezoelectric element in which the thickness of one layer of the piezoelectric ceramic layer is reduced without reducing the reliability Can be obtained to reduce the driving voltage. In addition, by changing the ratio of the length of the temperature compensation material to that of the laminated piezoelectric element, the linear expansion coefficient of the drive source can be controlled, and the freedom of selection of the mainframe material is increased. Also, the temperature difference between the laminated longitudinal effect piezoelectric element and the temperature compensation material during driving is smaller than that in the conventional case, and the reliability of the temperature compensation effect can be improved. [0002] Brief description of the drawings [0003] 1 and 2 show an embodiment embodying the present invention. FIG. 1 is a side view of a printing element, and FIG. 2 is a schematic perspective view of a drive source. 3 and 4 show a conventional device, and FIG. 3 is a side view of the printing element, and FIG. 4 is a schematic perspective view of a drive source. In the figure, 1 is a drive source, 3 is a base, 5 is a mover, 12 is a temperature compensation material, 42 is a piezoelectric ceramic layer, and 80 is a frame. 04-05-2019 6
© Copyright 2021 DropDoc