CN101596673B - Sandwich type piezoelectric transducer automatic assembly machine - Google Patents

Abstract

The invention discloses a sandwich type piezoelectric transducer automatic assembly machine. A push plate, a pressure plate, a support plate are sleeved on two vertical columns; wherein, the push plate axially slide along the vertical columns through a first copper bush; the pressure plate is fixed on the two vertical columns by a first screw nut to bear the axial pretightening force applied on the sandwich type piezoelectric transducer by a fuel tank; the support plate is fixed on the two columns by a second screw nut to install a first hydraulic motor; a second hydraulic motor is fixed on the push plate by a fourth screw nail, a vertical plate and a fifth screw nail; a jaw vice is fixed on the push plate by a bolt; the push plate axially slide along a guiding shaft through a second copper bush; the guiding shaft is mounted on a base by a screw thread; the first hydraulic motor drives a third screw nut of the sandwich type piezoelectric transducer to rotate by a first coupling and a dedicated sleeve, so as to generate axial pressure and press a piezoelectric ceramics tightly. In the invention, two hydraulic motors are adopted, therefore, the assembly precision and the assembly efficiency are high, the assembly operations is safe, and the assembly automation of the sandwich type piezoelectric transducer is realized.

Description

Automatic Assembly Machine for Sandwich Piezoelectric Transducers

technical field

The invention relates to the field of ultrasonic waves, in particular to an automatic assembly machine for sandwich piezoelectric transducers.

Background technique

Figure: With the rapid development of science and technology, intelligent ultrasonic equipment such as ultrasonic welding machines, ultrasonic cleaning machines, and ultrasonic processing machines have been more and more widely used, and the annual output is rapidly increasing at a rate of 15-20%. The sandwich piezoelectric transducer is the core device of intelligent ultrasonic equipment, and it is a high-efficiency, high-power electroacoustic conversion device. The sandwich piezoelectric transducer integrates the piezoelectric effect and the inverse piezoelectric effect. The assembly process of the sandwich piezoelectric transducer is the process of realizing the piezoelectric effect. The use process of the sandwich piezoelectric transducer It is the process of realizing the inverse piezoelectric effect.

The requirements of intelligent ultrasonic equipment for sandwich piezoelectric transducers are:

(1) The structure size is small, the instantaneous output power is 35-40w/cm ² , the continuous power is 7-8w/cm ² , and the power is large. 100~2200w;

(2) Less heat generation and low sound loss under long-term continuous and intermittent working conditions;

(3) Electroacoustic conversion efficiency > 80%;

(4) The sandwich piezoelectric transducer cannot be loosened when it is working;

(6) The piezoelectric ceramic sheet will not be broken under long-term working conditions;

(7) Low impedance, for a 15kHz 2200W sandwich piezoelectric transducer, its impedance is <12Ω.

(8) The capacitance is stable and the range of change is small.

However, due to the complex variability of ceramic materials, uneven particle distribution, complex sintering process, difficulty in controlling the flatness, roughness and parallelism of the radiating surface of sandwich piezoelectric transducer components, and pressure fluctuations, etc. , making it difficult for sandwich piezoelectric transducers to meet the above requirements. What is particularly prominent is that the development and production units of sandwich piezoelectric transducers in my country use torque wrenches to assemble sandwich piezoelectric transducers. The torque fluctuation range is 30-50Nm, and the piezoelectric fluctuation range is 3000-6000N, resulting in The frequency variation range of the sandwich piezoelectric transducer in mass production reaches 150-350Hz, the impedance variation range reaches 3-6Ω, and the capacitance variation range is 500-1200pf. The sandwich piezoelectric transducer has no clamping mechanism in the radial direction, so that the piezoelectric transducer will move in the radial direction (horizontal direction) during the assembly process, which may easily lead to scrapping of the sandwich piezoelectric transducer. The nut tightening mechanism of the piezoelectric transducer adopts a hydraulic torque wrench. During use, a column needs to be used to block the hydraulic torque wrench, and a counter torque is applied to the hydraulic torque wrench in the circumferential direction. Transducer nuts apply torque, increasing work time and sometimes causing operator injuries due to operator inattention. In the process of use, the conversion efficiency of the sandwich piezoelectric transducer is low, it is easy to generate heat, the ceramic sheet is easily broken, and the sandwich piezoelectric transducer is easy to loosen. The sandwich piezoelectric transducer and the ultrasonic generator Difficult to match and other issues, the production and application units of sandwich piezoelectric transducers urgently need to solve the above problems.

Contents of the invention

The object of the present invention is to overcome the deficiencies of the prior art, and provide an automatic assembly machine for sandwich piezoelectric transducers with no radial offset and dislocation of piezoelectric ceramic sheets and devices, safe assembly operation, and high-efficiency assembly.

In order to achieve the above object, the present invention takes the following measures:

The sandwich piezoelectric transducer automatic assembly machine includes a base, a column, a push plate, a first copper bush, a pressure plate, a first nut, a support plate, a second nut, a first hydraulic motor, a first coupling, Special sleeve, copper gasket, sandwich piezoelectric transducer, oil cylinder, first screw, second screw, positioning block, third screw, vise, second hydraulic motor, second coupling, fourth Screws, vertical plates, fifth screws, second copper bushings, guide shafts, third nuts, rear reflectors, piezoelectric ceramic sheets, electrodes, front reflectors, two columns are installed on the base through threads, and the oil cylinder passes through The first screw is fixed on the base, and the push plate, pressure plate, and support plate are set on the two columns, wherein the push plate slides axially along the column through the first copper bushing, and the pressure plate is fixed on the two columns through the first nut , to withstand the axial preload exerted by the oil cylinder on the sandwich piezoelectric transducer; the support plate is fixed on the two columns through the second nut for installing the first hydraulic motor, and the second hydraulic motor is fixed through the fourth screw , the vertical plate, and the fifth screw are fixed on the push plate, the vise is fixed on the push plate by bolts, the push plate slides axially along the guide shaft through the second copper bushing, the guide shaft is installed on the base through threads, the first The hydraulic motor drives the third nut of the sandwich piezoelectric transducer to rotate through the first coupling and a special sleeve to generate axial pressure and compress the piezoelectric ceramic sheet.

The present invention has the beneficial effect compared with prior art:

(1) High assembly precision;

(2) The assembly efficiency is high, and there is no need to manually adjust the radial misalignment of the piezoelectric ceramic sheet during the assembly process;

(3) The assembly operation is safe and will not cause personal injury due to worker misoperation;

(4) Two hydraulic motors are used to realize the assembly automation of the sandwich piezoelectric transducer;

The sandwich piezoelectric transducer automatic assembly machine can be widely used in the fields of assembly, production and scientific research of sandwich piezoelectric transducers of various shapes and specifications.

Description of drawings

Fig. 1 is a front view of an automatic assembly machine for a sandwich piezoelectric transducer;

Fig. 2 is a side view of the sandwich-type piezoelectric transducer automatic assembly machine;

Fig. 3 is a top view (A-A view) of the sandwich-type piezoelectric transducer automatic assembly machine;

Fig. 4 (a) is the front view of the structure of the sandwich piezoelectric transducer to be assembled in the present invention;

Fig. 4 (b) is the structural side view of the sandwich type piezoelectric transducer to be assembled of the present invention;

In the figure: base 1, column 2, push plate 3, first copper bushing 4, pressure plate 5, first nut 6, support plate 7, second nut 8, first hydraulic motor 9, first coupling 10 , special sleeve 11, copper gasket 12, sandwich piezoelectric transducer 13, oil cylinder 14, first screw 15, second screw 16, positioning block 17, third screw 18, vise 19, second hydraulic Motor 20, second coupling 21, fourth screw 22, vertical plate 23, fifth screw 24, second copper bushing 25, guide shaft 26, third nut 27, rear reflector 28, piezoelectric ceramic sheet 29 , electrode 30, front reflector 31.

Detailed ways

The sandwich piezoelectric transducer automatic assembly machine includes a base 1, a column 2, a push plate 3, a first copper bush 4, a pressure plate 5, a first nut 6, a support plate 7, a second nut 8, a first hydraulic pressure Motor 9, first coupling 10, special sleeve 11, copper gasket 12, sandwich piezoelectric transducer 13, oil cylinder 14, first screw 15, second screw 16, positioning block 17, third screw 18. Vice 19, second hydraulic motor 20, second coupling 21, fourth screw 22, vertical plate 23, fifth screw 24, second copper bushing 25, guide shaft 26, third nut 27, rear Reflector 28, piezoelectric ceramic sheet 29, electrode 30, front reflector 31, two columns 2 are installed on the base 1 by threads, oil cylinder 14 is fixed on the base 1 by the first screw 15, push plate 3, pressing plate 5. The support plate 7 is set on the two columns 2, wherein the push plate 3 slides axially along the column 2 through the first copper bushing 4, the pressure plate 5 is fixed on the two columns 2 through the first nut 6, and bears the oil cylinder 14 Axial preload applied to the sandwich piezoelectric transducer 13; the support plate 7 is fixed on the two columns 2 through the second nut 8 for installing the first hydraulic motor 9, and the second hydraulic motor 20 passes through The fourth screw 22, the vertical plate 23, and the fifth screw 24 are fixed on the push plate 3, the vise 19 is fixed on the push plate 3 by bolts, and the push plate 3 slides axially along the guide shaft 26 through the second copper bushing 25, The guide shaft 26 is installed on the base 1 through threads, and the first hydraulic motor 9 drives the third nut 27 of the sandwich piezoelectric transducer 13 to rotate through the first coupling 10 and the special sleeve 11 to generate an axial Pressure compresses the piezoelectric ceramic sheet 29.

The piston of the oil cylinder 14 pushes the push plate 3, the sandwich piezoelectric transducer 13, the copper gasket 12 and the hydraulic motor 20 upwards until the copper gasket 12 is in contact with the pressure plate 5, and a certain axial pre-stress is applied. tension. The axial pretightening force has two purposes: (1) to prevent the components of the sandwich piezoelectric transducer 13 from moving or misaligning horizontally during assembly; (2) the friction torque generated by the axial pretightening force is used to overcome During the tightening of the sandwich piezoelectric transducer 13 by the nut 27 , the torsional moment is generated by the output end of the front reflector 31 and the axial positioning plane of the vise 19 .

The sandwich piezoelectric transducer 13 includes a third nut 27, a rear reflector 28, a piezoelectric ceramic sheet 29, an electrode 30, and a front reflector 31. The front reflector 31 is equipped with bolts, and the rear reflector 28 is sleeved on the bolts. , piezoelectric ceramic sheet 29, electrode 30, and compress with the 3rd nut 27.

Working process of the present invention is as follows:

(1) First place the sandwich piezoelectric transducer 13 in the vise 19, and use the second hydraulic motor 20 to push the vise 19 to clamp the sandwich piezoelectric transducer 13 in the radial direction to ensure that the sandwich piezoelectric transducer 13 The piezoelectric transducer will not move in the radial direction (horizontal direction), and the sandwich piezoelectric transducer will not be scrapped.

(2) The piston of the oil cylinder 14 pushes the push plate 3, the sandwich piezoelectric transducer 13, the copper gasket 12 and the second hydraulic motor 20 upward together until the copper gasket 12 contacts the pressure plate 5, and applies Certain axial preload.

(3) The first hydraulic motor 9 drives the third nut 27 of the sandwich piezoelectric transducer 13 to rotate through the first coupling 10 and the special sleeve 11, and generates an axial force to compress the piezoelectric ceramic sheet 29, The magnitude of the axial force is controlled by the electric charge generated by the piezoelectric effect and the control system, which improves the assembly efficiency of the sandwich piezoelectric transducer and ensures the safety of workers.

Claims (1)

1. An automatic assembly machine for sandwich piezoelectric transducers, characterized in that it includes a base (1), a column (2), a push plate (3), a first copper bushing (4), and a pressure plate (5) , the first nut (6), the support plate (7), the second nut (8), the first hydraulic motor (9), the first coupling (10), the special sleeve (11), the copper gasket (12 ), sandwich piezoelectric transducer (13), oil cylinder (14), first screw (15), second screw (16), positioning block (17), third screw (18), vise (19 ), the second hydraulic motor (20), the second coupling (21), the fourth screw (22), the vertical plate (23), the fifth screw (24), the second copper bushing (25), the guide shaft (26), the sandwich piezoelectric transducer (13) includes a third nut (27), a rear reflector (28), a piezoelectric ceramic sheet (29), an electrode (30), and a front reflector (31), The two columns (2) are installed on the base (1) through threads, the oil cylinder (14) is fixed on the base (1) through the first screw (15), the push plate (3), the pressure plate (5), the support plate (7) Set on two columns (2), wherein the push plate (3) slides axially along the column (2) through the first copper bushing (4), and the pressure plate (5) is fixed by the first nut (6) On the two columns (2), bear the axial pre-tightening force exerted by the oil cylinder (14) on the sandwich piezoelectric transducer (13); On a column (2), it is used to install the first hydraulic motor (9), and the second hydraulic motor (20) is fixed on the push plate (24) by the fourth screw (22), the vertical plate (23) and the fifth screw (24). 3), the vise (19) is fixed on the push plate (3) by bolts, the push plate (3) slides axially along the guide shaft (26) through the second copper bushing (25), and the guide shaft (26) passes through Threaded on the base (1), the first hydraulic motor (9) drives the third nut of the sandwich piezoelectric transducer (13) through the first coupling (10) and special sleeve (11) (27) rotates, produces axial pressure, compresses piezoelectric ceramic sheet (29).

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