KR100768889B1 - Tiny ultrasonic linear actuator array and the manufacturing method thereby - Google Patents

Abstract

A tiny ultrasonic linear actuator array and a manufacturing method thereof are provided to be mounted on a printed circuit board without deterioration of efficiency. A tiny ultrasonic linear actuator array includes a plurality of tiny ultrasonic linear actuators(120), a supporting frame(110), and supporting arms(130). The plurality of tiny ultrasonic linear actuators(120) have various shapes such as a rectangular type, a linear type, a circular type, an ellipse type, a polygon type, a star type, and a heart type. The supporting frame(110) is contacted to a printed pattern of a printed circuit board simultaneously while supporting the elastic sheets of the tiny ultrasonic linear actuators(120). The supporting arms(130) connect the elastic sheets to each other or the elastic sheets to the supporting frame(110).

Description

Tiny ultrasonic linear actuator array and the manufacturing method

1 is an installation state diagram for explaining the operation principle of a single small ultrasonic linear actuator,

2A and 2B are plan and front views, respectively, of a small ultrasonic linear actuator array according to an embodiment of the present invention;

3A to 3F are schematic plan and side views for explaining a method for manufacturing a compact ultrasonic linear actuator array of the present invention;

4 is a process flowchart for explaining a method for manufacturing a compact ultrasonic linear actuator array of the present invention;

5 is an exploded perspective view illustrating a mounting process of a small ultrasonic linear actuator array of the present invention on a printed circuit board.

*** Explanation of symbols for the main parts of the drawing ***

10: vibrating body, 12: elastic sheet,

14, 16: piezoceramic sheet, 20: movable shaft support,

30, 32: bearing rubber ring, 40: moving shaft,

50: moving object, 100: TULA array,

100B: elastic sheet disc, 110: support frame,

120: monolithic TULA, 121: individual elastomeric sheet,

122, 123: individual piezoceramic sheets, 122a, 123a, 124a: adhesive,

124: moving shaft, 200: printed circuit board

The present invention relates to a compact ultrasonic linear actuator array and a method of manufacturing the same.

In case of small stepping motor that can be mounted for camera lens driving such as mobile phone or PDA (Personal Digital Assistant), reduction gear and cam should be used to convert fast rotation to linear movement. Due to backlash, errors occur and power consumption is very limited. In addition, such a stepping motor has disadvantages such as high current and heat generation.

In order to solve this problem, the present applicant has applied for an ultrasonic linear actuator using piezoelectric / electrical distortion elements as a patent application No. 14050 in 2004 and registered as a patent No. 443438. Refers to the generation of mechanical deformation when an electric field is applied to a crystal. Electrodistortion refers to a phenomenon in which mechanical deformation, or distortion, occurs when an electric field is applied to an electrodistortion material. Hereinafter, piezoelectric / electrical distortion elements are collectively referred to as 'piezoelectric elements', and ceramic materials are mainly used. This is commonly referred to as a 'piezoelectric ceramic' device. On the other hand, the name of the ultrasonic actuator is because the driving frequency is in the ultrasonic band, hereinafter, the small ultrasonic linear actuator is also called 'TULA' after the English name Tiny Ultrasonic Linear Actuator.

1 is an installation state diagram for explaining the operation principle of a single small ultrasonic linear actuator. As shown in FIG. 1, a general single TULA is formed on both the upper and lower surfaces (uni-morph type) or the upper and lower surfaces (bi-morph type) of the elastic sheet 12 and the elastic sheet 12, which are largely composed of a brass plate or the like. A moving shaft 40 attached to the center of the upper surface side piezoceramic sheet 14 of the piezoceramic sheets 14 and 16 to be attached and perpendicular to the sheet surface in the center of the piezoelectric ceramic sheet 14 of the vibrating body 10. ), The moving body 50 frictionally inserted into the moving shaft 40 to move forward and backward on the moving shaft 40, the moving shaft support 40 supporting both ends of the moving shaft 40, and the moving shaft support 20. It can be made to include a bearing rubber ring 30, 32 for supporting the moving shaft 50 while allowing the forward and backward movement of the moving shaft (50).

In the above-described configuration, the vibrating body 10 may be implemented as a disc-shaped sheet or a square sheet, the moving shaft 40 may be made of a light and durable material, for example, carbon fiber material.

However, the single TULA as described above and a method of manufacturing the same are suitable only for the movement of a single object, such as driving a zoom lens of a digital camera, but in fields requiring multiple TULA assemblies, for example, an electron whose output varies according to a desired input. In the field that requires a large number of line or matrix type TULA array, such as braille plate, there was a problem that is inefficient.

The present invention was devised to solve the above-mentioned problems. The present invention provides a small ultrasonic linear actuator array that requires a plurality of small ultrasonic linear actuators in a batch process and at the same time does not reduce the efficiency of a printed circuit board or other mechanical parts. It is an object of the present invention to provide a small ultrasonic linear actuator array and a method for manufacturing the same, which can be mounted simply and easily.

Small ultrasonic linear actuator array of the present invention for achieving the above object is in the vertical direction from the upper surface or the lower surface of the elastic sheet, the piezoelectric ceramic sheet is attached to the upper and lower surfaces and the upper piezoceramic sheet surface in the vertical direction A plurality of ultrasonic linear actuators including an attached moving shaft and a moving body frictionally inserted into the moving shaft to move forward and backward on the moving shaft; And at least two support arms interconnecting the elastomer sheets, and a support frame connected to the support arms of the elastomer sheets present at edges thereof to contact the electrode patterns of the printed circuit board.

On the other hand, the method of manufacturing a small ultrasonic linear actuator array of the present invention comprises the steps of (a) preparing an elastic sheet disc; (b) an ultrasonic wave comprising a plurality of individual elastic sheets constituting the plurality of ultrasonic linear actuator arrays by processing the elastic sheet discs, a support arm for interconnecting the individual elastic sheets, and a support frame in contact with an electrode pattern of a printed circuit board; Forming a linear actuator array pattern; (c) applying a piezoceramic exclusive adhesive to the top or bottom or top / bottom of the individual elastic sheet; (d) thermosetting the adhesive after attaching the individual piezoceramic sheets on the adhesive; (e) spot coating the coaxial fixing adhesive on the upper surface side of the individual piezoceramic sheet; and (f) collectively attaching a moving shaft on the spot coated adhesive layer.

Hereinafter, a small ultrasonic linear actuator array and a method of manufacturing the same according to a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings.

2A and 2B are plan and front views, respectively, of a small ultrasonic linear actuator array in accordance with one embodiment of the present invention. As shown in Fig. 2, the TULA array according to an embodiment of the present invention may have a specific shape such as a rectangular or line, circular, elliptical, polygonal or star-shaped or heart-shaped like this embodiment. A plurality of TULA 120 forming the shape, the support frame 110 and the individual TULA in contact with the printed pattern of the printed circuit board (not shown) while supporting the elastic sheet 121 of the TULA 120 located at the edge It may include a support arm 130 for connecting the elastic sheet 121 of 120 to each other or to the support frame 110.

In the above-described configuration, the individual elastic sheet 121, the support arm 130 and the support frame 110 can be formed by processing an elastic sheet disc made of a single body, such elastic sheet disc is a predetermined thickness For example, it may be made of a predetermined material of 0.2 mm thickness, for example brass or phosphor bronze. The individual elastic sheet 121 of each TULA 120 may be formed in a circular, rectangular or other shape, and furthermore, the length and width of the support arm 130 may vary depending on the size and shape of the individual elastic sheet 121. There will be.

On the other hand, the individual TULA 120 is attached to both the upper and lower surfaces (uni-morph type) or the upper and lower surfaces (bi-morph type) of the individual elastic sheet 121 and the individual elastic sheet 121 as described above. The piezoelectric ceramic sheets 122 and 123 are frictionally inserted into the moving shaft 124 and the moving shaft 124 attached in a direction perpendicular to the sheet surface at the center of the individual piezoelectric ceramic sheet 123 on the upper surface side. It may comprise a moving body 125 moving forward / backward on an axis 124, where parts of suitable shape and structure may be mounted to this moving body, depending on the application aspect.

3A to 3F are schematic plan views and side views for explaining a method for manufacturing a compact ultrasonic linear actuator array according to the present invention, and FIG. 4 is a process flowchart for explaining a method for manufacturing a compact ultrasonic linear actuator array according to the present invention. As shown in FIG. 4, first, in step S10, a brass plate or a phosphor bronze plate to be used as the elastic sheet disc 100B is prepared. Such an elastic sheet disc 100B may be implemented with a thickness of, for example, 0.2 mm. In this embodiment, as illustrated in FIG. 3A, an elastic sheet disc 100B formed of a circular plate is illustrated.

Next, in step S12, the prepared elastic sheet disc is processed to form a TULA array pattern. As the processing method, a known etching method is preferably used. That is, the photoresist is applied to the upper and rear surfaces of the elastic sheet original plate 100B, and a mask having a TULA array pattern formed thereon is placed thereon, and again irradiated with UV (Ultra Violet) light from the upper portion of the mask to form the TULA array pattern. The photoresist pattern may be formed by exposing the photoresist pattern, and a desired TULA array pattern may be formed on the elastic sheet disc by removing the portion where the photoresist pattern is formed by etching.

Figure 3b shows a state in which the desired TULA array pattern is formed on the elastomer sheet 100B by step S12, reference numeral CL is separated from the elastomer sheet original plate 100B after the manufacture of the TULA array 100 is completed. The cutting line for this is shown. And from FIG. 3C, process is demonstrated by this sectional drawing which cut | disconnected the line A-A of FIG. 3B.

4, in step S14, as shown in FIG. 3C, epoxy resins 122a and 122b dedicated to piezoelectric ceramics for the upper and lower surfaces or upper and lower surfaces of the individual elastic sheet of the TULA array pattern are collectively applied. For example, it may be printed and applied by a printing method using an aeroprinter.

Next, in step S16, the piezoceramic sheets 122 and 123 are attached to the epoxy resins 122a and 123a thus applied as shown in FIG. 3D, which is also applied to the piezoceramic sheet automatic feeding equipment. It can be attached in a batch. Next, in step S18, the piezoceramic sheets 122 and 123 are applied to the epoxy resins 122a and 123a to which the piezoelectric ceramic sheets 122 and 123 are attached to be cured. This step S18 may be performed using CB (Ceramic Bonding) equipment. Can be.

In this way, after the manufacturing process for the vibrating body is completed, in step S20, the epoxy resin 124a for fixing the moving shaft is attached to the moving shaft 124 on the upper side piezoelectric ceramic sheet 123 as shown in FIG. 3E. In spot application, this step S20 may be performed using an Automatic Ejcetion (AE) equipment.

Next, in step S22, the moving shaft 124 is collectively attached to the spot-coated epoxy resin 124a using a shaft fixing jig as shown in FIG. 3F, and again, in step S24, the above-mentioned CB equipment is used. Thus, the epoxy resin 124a between the vibrating body and the moving shaft 124 is cured.

Next, the produced TULA array 100 is separated from the elastic sheet original plate 100B by cutting the cutting line CL of the elastic sheet original plate 100B. Finally, by inserting the moving bodies 125 into the respective moving shafts 124 of the TULA array thus manufactured, the production of the TULA array is finally completed. Of course, it is necessary to connect the electrode lines to the individual piezoceramic sheets 122 and 123 afterwards, which may be implemented as FPCB (Flexible Printed Circuit Board).

5 is an exploded perspective view illustrating a mounting process of a small ultrasonic linear actuator of the present invention on a printed circuit board. As shown in FIG. 5, when the TULA array 100 of the present invention is mounted on a printed circuit board 200, the printed circuit board 200 may correspond to, for example, the shape and width of the support frame 110. By simple operation of placing and soldering on the electrode pattern 220 printed in a box shape, the electrode soldering work to the elastic sheet 121 of TULA can be completed in one operation. In this case, the portion where the TULA array 100 of the printed circuit board 200 is located is preferably formed as an empty space 210 to ensure smooth vibration of the vibrating body.

The small ultrasonic linear actuator array of the present invention and a method of manufacturing the same are not limited to the above-described embodiments and can be modified in various ways within the scope of the technical idea of the present invention. For example, unlike in the embodiment shown in FIG. 2, the space between any support arms connected to the individual elastic sheets may be actual, in which case the number of support arms is reduced to two or three. It could be increased to four or more.

According to the small ultrasonic linear actuator array and the manufacturing method of the present invention as described above, a small ultrasonic linear actuator array requiring a large number of small ultrasonic linear actuator by a batch process and at the same time without reducing the printed circuit It is possible to mount on the substrate simply and efficiently.

Claims (3)

Each of the vibrating bodies formed by attaching a piezoceramic sheet to an upper surface or a lower surface or an upper surface and a lower surface of the elastic sheet and a moving shaft attached to the vertical direction from the upper piezoelectric ceramic sheet surface and frictionally inserted into the moving shaft on the moving shaft. A plurality of ultrasonic linear actuators having a moving body moving forward and backward; At least two support arms interconnecting the elastomer sheets, respectively; And a support frame connected to the support arm of the elastic sheet existing at an edge thereof and in contact with the electrode pattern of the printed circuit board. (a) preparing an elastic sheet disc; (b) an ultrasonic wave comprising a plurality of individual elastic sheets constituting the plurality of ultrasonic linear actuator arrays by processing the elastic sheet discs, a support arm for interconnecting the individual elastic sheets, and a support frame in contact with an electrode pattern of a printed circuit board; Forming a linear actuator array pattern; (c) applying a piezoceramic exclusive adhesive to the top or bottom or top / bottom of the individual elastic sheet; (d) thermosetting the adhesive after attaching the individual piezoceramic sheets on the adhesive; (e) dot coating a moving shaft fixing adhesive on the upper surface side of the individual piezoceramic sheet; and (F) a method of manufacturing a compact ultrasonic linear actuator array comprising the step of attaching the moving shaft in a batch on the point-coated adhesive. The method of claim 2, wherein the adhesive is an epoxy resin.

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