CN201075843Y - Short column type ultrasound wave electric machine - Google Patents

Abstract

The utility model relates to a short columnar type ultrasonic motor and belongs to the technical field of ultrasonic motor manufacture, consisting of a stator, a rotor and a mounting fixing base. An upper fitting block and a lower fitting block of the stator are screw thread fit mechanism. The upper fitting block and the lower fitting block of the stator clamp a piezoceramics and lock tightly to form the stator. The rotor and a shaft are assembled together through a fixing screw. A fixing nut and a gasket lead the rotor to be pressed on the stator with a certain pre-pressure. The overall length of the stator is short and the rotor adopts an elastic supporting structure so as to improve the operation performance of the motor. The stator of the motor is arranged on the fixing base. The fixing base takes a shape of rhombus and is provided with an elastic supporting thin plate. The two ends of the fixing base are provided with two fixing mounting holes which can fix the whole motor on a position to be arra.

Description

Short column type ultrasonic motor

technical field

The utility model relates to a head-shaking ultrasonic motor, in particular to a short-column ultrasonic motor, which belongs to the technical field of ultrasonic motor manufacturing.

Background technique

Ultrasonic motor is a motor with a new driving principle. Compared with traditional electromagnetic motors, ultrasonic motors no longer use coils, and use piezoelectric ceramic inverse piezoelectric effects and frictional coupling between stators and rotors to complete the motor from electric energy to torque output energy. conversion. Therefore, compared with electromagnetic motors, ultrasonic motors have the advantages of fast response, low speed and high torque, no input self-locking, and no electromagnetic interference. The research on the cylindrical oscillating head ultrasonic motor started late. It adopts the Langevin vibrator structure. The motor stator uses a metal matching block to lock the piezoelectric ceramic. The motor assembly does not require bonding. The assembly process is simple, the cost is low, and it is convenient for automatic production. Therefore, the cylindrical shaking head ultrasonic motor has a wide range of applications in precision optical instruments, high-precision tracking servo control devices, and camera focusing.

Since the stator of the cylindrical oscillating head ultrasonic motor adopts the Langevin oscillator structure, in order to improve the energy conversion efficiency of the motor, the ratio between the length and diameter of the general stator needs to be greater than 2 times, and the oscillating motion of the stator is generated by the synthesis of two orthogonal bending vibrations of the stator. . Therefore, the overall structural length of the cylindrical oscillating head type ultrasonic motor is relatively long, which brings some problems to practical applications. In the current cylindrical oscillating head type ultrasonic motor, since the fixing of the stator will greatly affect its resonance mode, there are always problems in the fixing of the motor, which makes it difficult to apply the motor in a high-precision servo drive system. The utility model proposes a short-column ultrasonic motor, the ratio of the stator length to the diameter is close to 1:1, which greatly shortens the structural size of the motor. In the embodiment, the diameter of the motor stator is 15 mm, and the overall motor height is 18.5 mm. A fixed base structure with elastic support is proposed, so that when the motor is fixed to the position to be installed, the vibration amplitude of the motor stator is not affected, so that the impact on the normal operation of the motor is reduced to a small extent.

technical content

Technical problem: The purpose of this utility model is to provide a short-column ultrasonic motor, which greatly shortens the length of the motor while keeping the performance of the motor unchanged; Under the circumstances, the motor can be well fixed, so that the motor can be applied in a high-precision servo drive system.

Technical solution: The short-column ultrasonic motor of the present invention includes a stator, a rotor, a fixed base, and a shaft. The stator of the motor consists of an upper matching block on the stator, a lower matching block on the stator, a bearing, an upper piezoelectric ceramic, and a lower piezoelectric ceramic. Composed of ceramics and electrode sheets, a bearing is provided in the middle of the outer periphery of the shaft, and a lower matching block of the stator is arranged on the outer periphery of the bearing. The upper end of the electric ceramic is provided with an upper piezoelectric ceramic, and the upper end of the upper piezoelectric ceramic is provided with an upper matching block of the stator. The upper end of the upper piezoelectric ceramic and the lower end of the lower piezoelectric ceramic are tightly fitted between the upper matching block of the stator and the lower matching block of the stator. , the matching block on the stator is threadedly matched with the matching block on the lower stator, the rotor is arranged at the upper end of the matching block on the stator, the rotor and the shaft are connected by fixing screws, the fixing nut is set on the lower end of the matching block under the stator, and the fixed nut is connected with the matching block on the lower stator Gaskets are arranged between the upper piezoelectric ceramics and the lower piezoelectric ceramics, and four electrode pieces are arranged between the upper piezoelectric ceramics and the lower piezoelectric ceramics. The rotor is connected to the upper matching block of the stator through an elastic member; the lower end of the lower matching block of the stator is connected to the fixed base through a thin plate.

The connecting piece of the above-mentioned short-column ultrasonic motor is to open an upper outer ring groove, an inner groove, and a lower outer ring groove on the lower disc body of the elastic rotor, and the height from the bottom of the upper outer ring groove to the lower end of the connecting piece is 36% of the height of the elastic rotor , the height of the lower outer ring groove is 15% of the height of the elastic rotor, the width of the lower end of the connector is between 3% and 6% of the diameter of the elastic rotor, and the electrode sheets include a first electrode sheet, a second electrode sheet, a third electrode sheet, The fourth electrode sheet, each electrode sheet is equally distributed between the upper piezoelectric ceramic and the lower piezoelectric ceramic, the first electrode sheet and the third electrode sheet are a pair of electrodes, and the second electrode sheet and the fourth electrode sheet are a pair of electrodes , the piezoelectric ceramic regions corresponding to each pair of electrode sheets are polarized in opposite phases to each other, the elastic rotor and the shaft are connected by fixing screws, the thin plate is made of polymer, and the thin plate and the matching block under the stator are glued together.

Beneficial effects: the utility model is to provide a short-column ultrasonic motor. Compared with the general column-shaped oscillating-head ultrasonic motor, its structural size is short and small, the diameter of the stator is 15 mm, and the length of the motor is 18.5 mm. This short-column ultrasonic motor adopts an elastic fixed base, which can conveniently fix the motor at the position to be installed, and does not affect the operation of the motor so that the motor can be used in high-precision servo drive systems. The manufactured short-column ultrasonic motor with a diameter of 15mm has a wide operating frequency range and can run stably from 39kHz to 43kHz. The maximum speed exceeds 200r/min, the minimum speed is close to 8r/min, and the motor stall torque is 180gcm.

Description of drawings

Fig. 1 is the general structural diagram of the present utility model. Among them: fixed screw 1, elastic rotor 2, stator upper matching block 3, bearing 4, upper piezoelectric ceramic 5, lower piezoelectric ceramic 6, fixed base 7, lower stator matching block 8, electrode sheet 9, gasket 10, Fixed nut 11, shaft 12, thin plate 13, connecting piece 14.

Fig. 2 is a schematic diagram of the piezoelectric ceramic structure of the present invention. Among them, "+" means normal phase polarization, and "-" means reverse phase polarization. There are: a first electrode sheet 91 , a second electrode sheet 92 , a third electrode sheet 93 , and a fourth electrode sheet 94 .

Fig. 3 is a structural schematic diagram of the connector of the present invention.

Fig. 4 is a schematic structural view of the elastic rotor of the present invention. Wherein there are: upper outer ring groove 21, inner groove 22, lower outer ring groove 23.

Detailed ways

Below is the specific embodiment of the utility model to further describe:

Embodiment one:

The short-column ultrasonic motor of the utility model is composed of fixing screws, a rotor, an upper matching block of a stator and a lower matching block of a stator, a bearing, a piezoelectric ceramic, a fixing base, a fixing nut and a gasket. The upper matching block of the stator and the lower matching block of the stator are threaded matching mechanisms, which clamp piezoelectric ceramics and lock to form the stator. The shaft is held together by means of set screws, set nuts and washers which press the rotor against the stator with a certain preload. The rotor of the motor is an elastic rotor 2, and the lower part of the elastic rotor 2 is a connecting piece 14, and after a preload is applied, the rotor produces elastic deformation. The flexible rotor has a diameter of 15mm and this motor has a length of 18.5mm. It can run stably at 39kHz-43kHz. When the wall thickness of the lower end of the connecting piece 14 is 0.45mm, the maximum speed of the motor is 180rpm, the surface wear of the motor stator increases obviously, the stall torque is about 50g·cm, and the noise of the motor is relatively large.

Fig. 2 is that the stator of the short-column ultrasonic motor of the present invention includes 2 piezoelectric ceramics and 4 electrode sheets, the 2 piezoelectric ceramics are the same, and 4 electrodes are evenly distributed between the 2 piezoelectric ceramics, which is 4 a polarized area. Two pieces of piezoelectric ceramics are symmetrically stacked together, and the excitation voltage is applied to the piezoelectric ceramics through the electrode sheets between each pair of electrodes. The stator of the motor is installed on the fixed base, which is rhombus-shaped, and is provided with an elastic supporting polymer sheet. There are two fixed mounting holes at both ends, which can fix the entire motor at the position to be installed.

Embodiment two:

The short-column ultrasonic motor of the utility model is composed of fixing screws, a rotor, an upper matching block of a stator and a lower matching block of a stator, a bearing, a piezoelectric ceramic, a fixing base, a fixing nut and a gasket. The upper matching block of the stator and the lower matching block of the stator are threaded matching mechanisms, which clamp piezoelectric ceramics and lock to form the stator. The shaft is held together by means of set screws, set nuts and washers which press the rotor against the stator with a certain preload. The rotor of the motor is an elastic rotor 2, and the lower part of the elastic rotor 2 is a connecting piece 14, and after a preload is applied, the rotor produces elastic deformation. The flexible rotor has a diameter of 15mm and this motor has a length of 18.5mm. It can run stably at 39kHz-43kHz. When the wall thickness of the lower end of the connecting piece 14 is 0.75mm, the maximum speed of the motor is 200rpm, the stall torque is about 180g·cm, and the motor runs smoothly and without noise.

Fig. 2 is that the stator of the short-column ultrasonic motor of the present invention includes 2 piezoelectric ceramics and 4 electrode sheets, the 2 piezoelectric ceramics are the same, and 4 electrodes are evenly distributed between the 2 piezoelectric ceramics, which is 4 a polarized area. Two pieces of piezoelectric ceramics are symmetrically stacked together, and the excitation voltage is applied to the piezoelectric ceramics through the electrode sheets between each pair of electrodes. The stator of the motor is installed on the fixed base, which is rhombus-shaped, and is provided with an elastic supporting polymer sheet. There are two fixed mounting holes at both ends, which can fix the entire motor at the position to be installed.

Embodiment three:

The short-column ultrasonic motor of the utility model is composed of fixing screws, a rotor, an upper matching block of a stator and a lower matching block of a stator, a bearing, a piezoelectric ceramic, a fixing base, a fixing nut and a gasket. The upper matching block of the stator and the lower matching block of the stator are threaded matching mechanisms, which clamp piezoelectric ceramics and lock to form the stator. The shaft is held together by means of set screws, set nuts and washers which press the rotor against the stator with a certain preload. The rotor of the motor is an elastic rotor 2 , and the contact part with the stator is a connecting piece 14 , and after a preload is applied, the rotor produces elastic deformation. The flexible rotor has a diameter of 15mm and this motor has a length of 18.5mm. It can run stably at 39kHz to 43kHz. When the wall thickness of the lower end of the connector 14 is 0.9mm, the maximum speed of the motor is 100rpm, the surface wear of the motor stator increases obviously, the stall torque is about 80g·cm, and the noise of the motor becomes larger.

Fig. 2 is that the stator of the short-column ultrasonic motor of the present invention includes 2 piezoelectric ceramics and 4 electrode sheets, the 2 piezoelectric ceramics are the same, and 4 electrodes are evenly distributed between the 2 piezoelectric ceramics, which is 4 a polarized area. Two pieces of piezoelectric ceramics are symmetrically stacked together, and the excitation voltage is applied to the piezoelectric ceramics through the electrode sheets between each pair of electrodes. The stator of the motor is installed on the fixed base, which is rhombus-shaped, and is provided with an elastic supporting polymer sheet. There are two fixed mounting holes at both ends, which can fix the entire motor at the position to be installed.

Claims (4)

1. a short column type ultrasonic motor, this motor comprises stator, elastic rotor (2), fixed base (7), pad (10), axle (12), it is characterized in that the stator of this motor is formed by matching block on the stator (3), the lower matching block of the stator (8), the bearing (4), the upper piezoelectric ceramic (5), the lower piezoelectric ceramic (6), and the electrode sheet (9). The bearing (4) is provided with an upper stator matching block (3) and a lower stator matching block (8) on the outer periphery of the bearing (4), the lower stator matching block (8) is connected with the bearing (4), and the stator upper matching block (3 ) and the upper part of the lower matching block (8) of the stator are threaded, and the upper end of the upper piezoelectric ceramic (5) and the lower end of the lower piezoelectric ceramic (6) are closely matched to the upper matching block (3) of the stator and the lower matching block of the stator (8), four electrode sheets (9) are arranged between the upper piezoelectric ceramic (5) and the lower piezoelectric ceramic (6), and an elastic rotor (2) is arranged at the upper end of the matching block (3) on the stator, The lower part of the elastic rotor (2) is provided with a connecting piece (14), the lower end of the connecting piece (14) is in contact with the upper end of the matching block (3) on the stator, the elastic rotor (2) is connected to the shaft (12), and the lower end of the stator is matched The lower end of the block (8) is provided with a fixed nut (11), and a gasket (10) is provided between the fixed nut (11) and the matching block (8) under the stator, and the lower end of the outer peripheral protrusion of the matching block (8) under the stator passes through the Thin plate (13) is connected on the fixed base (7). 2. The short column type ultrasonic motor according to claim 1, characterized in that the connecting piece (14) is to open the upper outer ring groove (21) and the inner groove ( 22), the lower outer ring groove (23), the height from the bottom of the upper outer ring groove (21) to the lower end of the connector (14) is 36% of the height of the elastic rotor (2), and the height of the lower outer ring groove (23) is elastic 15% of the height of the rotor (2), and the wall thickness of the lower end of the connecting piece (14) is between 3% and 6% of the diameter of the elastic rotor (2). 3. The short column type ultrasonic motor according to claim 1, characterized in that said electrode piece (9) comprises a first electrode piece (91), a second electrode piece (92), a third electrode piece (93) , the fourth electrode sheet (94), each electrode sheet is equally distributed between the upper piezoelectric ceramics (5) and the lower piezoelectric ceramics (6), the first electrode sheet (91) and the third electrode sheet (93) are one As for the counter electrode, the second electrode piece (92) and the fourth electrode piece (94) are a pair of electrodes, and the piezoelectric ceramic regions corresponding to each pair of electrode pieces are mutually oppositely polarized. 4. The short column type ultrasonic motor according to claim 1, characterized in that the elastic rotor (2) and the shaft (12) are connected by fixing screws (11), and the thin plate (13) is made of polymer nylon , the thin plate (13) and the matching block (8) under the stator are bonded together with epoxy glue.

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