Piezoelectric driven dual speed stage

Abstract

A piezoelectric driven dual-speed workbench, the base is installed with a vibrator support frame, a guide rail, and a slider by screws, a grating ruler is fixed on it, a clutch device and a guide device are installed on the upper support seat and the lower support seat, the flexible support plate of the drive device is connected to the vibrator support frame by screws, the drive plate is installed at the tail end of the guide device, the inner side is connected to the guide device by bolts, the outer side is affixed with friction material to contact the drive foot of the drive device, and the upper support seat is connected to the upper workbench through a box. The advantage is that through the piezoelectric vibrator and structural connection, a periodically alternating electrical signal is passed to form a torsional mode, and under the action of friction, the drive plate can be freely driven to move back and forth. That is, the original driving form in the process of moving the workbench is changed, and different workpieces can be moved at different speeds and with different working requirements during the work of the workbench.

Description

Technical Field

[0001] The invention belongs to a piezoelectric driven double-speed workbench. Background Art

[0002] The workbench plays a huge role in the production process of the enterprise, facilitating the storage, transportation and processing of products. During the transportation process, the workbench is the guarantee for the mechanized and automated transportation and processing of products.

[0003] The principles of various workbenches are roughly the same. They all control the moving direction of the workbench by contacting the limit or reversing device on the workbench with the reversing switch. They all use weak electricity to control strong electricity, but the CNC is done through a feedback device. However, they all use motors (servo motors or AC and DC motors) to transmit to the screw (ordinary screw or ball screw) to complete the movement of the workbench. The working principle of the traditional workbench is relatively simple, but it is difficult to implement because it involves complex circuits and complex mechanical structures. Summary of the invention

[0004] The purpose of the present invention is to solve the above-mentioned existing problems, change the original driving form during the movement of the workbench, and realize a piezoelectric driven dual-speed workbench that moves different workpieces at different speeds and different working requirements during the operation of the workbench.

[0005] The present invention is implemented as follows: the base of the double-speed workbench is installed with a vibrator support frame and a lower guide rail by screws, a lower slider is installed on the lower guide rail, a lower support plate is connected to the lower guide rail, a lower support seat is connected to the lower support plate by screws, an upper support seat is fixed to the upper support plate by set screws, a clutch device and a guide device are installed on the upper support seat and the lower support seat; the clutch device is fixed to the upper support seat and the lower support seat by a positioning plate and positioning screws, and the guide device is fixed to the upper support seat and the lower support seat by a shaft shoulder and a clamping ring; a flexible support plate of a driving device is connected to the vibrator support frame by screws, a driving plate is installed at the tail end of the guide device, the inner side is connected to the guide device by bolts, a friction material is attached to the outer side to contact with the driving foot of the driving device, and the upper The support seat is connected to the box body by screws, the box body is connected to the upper worktable, the lower worktable is installed on the upper part of the lower support seat, the upper slider is installed on the upper guide rail, the upper slider is connected to the upper support plate, the upper slider and the lower slider are both equipped with locking devices and grating scales, the guide device is connected by fixing screws, spring preload screws, springs, guide shafts, clamps, guide sleeves, and gaskets; the driving device is connected by positioning nut A, piezoelectric ceramic group A for bending, piezoelectric ceramic group B for torsion, positioning sleeves, flexible supporting plates, elastic rods, and driving feet, that is, the elastic rod of the driving device is equipped with flexible supporting plates, positioning sleeves, piezoelectric ceramic group B for torsion, driving feet, and piezoelectric ceramic group A for bending, and the end is fixed with positioning nut A. The clutch device is connected by positioning nut, intermediate sleeve, piezoelectric ceramic group, positioning plate, and elastic rod, that is, the elastic rod of the clutch device is equipped with positioning plate, piezoelectric ceramic group, intermediate sleeve, and the end is fixed by positioning nut. The locking device is composed of a lock core a, a supporting plate, a piezoelectric ceramic group, a spring, a gasket and a lock core b. That is, the lock core a of the locking device is connected to the lock core b and a spring is installed, and a piezoelectric ceramic group, a supporting plate and a gasket are installed on the lock core a and the lock core b.

[0006] The advantages of the present invention are:

[0007] 1. The piezoelectric ceramics used are used as piezoelectric vibrators. When the piezoelectric ceramic group A 7-2 is passed through a periodic alternating electrical signal, the piezoelectric vibrator forms a second-order bending vibration mode, the driving foot contacts the driving plate, applies pressure to the driving plate, and at the same time, the piezoelectric ceramic group B 7-3 is energized, and the vibrator forms a torsion mode. At this time, the bending and torsion are compounded, and under the action of friction, the driving plate 8 (mover) can be freely driven to move back and forth. That is, the original driving form in the process of moving the workbench is changed, and the working mode of moving different workpieces at different speeds and different working requirements during the working process of the workbench is realized;

[0008] 2. Compact structure, short transmission route, high torque density, low speed and high torque, no need for gear speed mechanism, greatly reducing the number of moving pairs, and can achieve direct drive. Therefore, compared with other systems, it greatly reduces the impact of vibration and noise, energy loss and transmission errors, and greatly improves the positioning accuracy and response speed of the system;

[0009] 3. Self-locking when power off. The locking device is designed by utilizing the piezoelectric properties of piezoelectric ceramics. Once the power is cut off, the locking device will lock immediately with fast response.

[0010] 4. The vibrator has small vibration inertia, fast response (millisecond level), and large holding torque. Since the structure is based on the piezoelectric effect and friction transmission is used between the vibrator (drive device) and the drive plate, it can rise from static to stable bending and torsion mode within milliseconds, and the braking response is faster due to the effect of friction. At the same time, the number of vibrators can be increased or decreased according to the required driving force. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 It is a front view of the structure of the present invention;

[0012] Figure 2 It is a left side view of the structure of the present invention;

[0013] Figure 3 A top view of the structure of the present invention;

[0014] Figure 4 It is a schematic diagram of the driving device of the present invention;

[0015] Figure 5 It is a schematic diagram of the clutch device of the present invention;

[0016] Figure 6 It is a schematic diagram of the locking device of the present invention;

[0017] Figure 7 It is a schematic diagram of the guide device of the present invention;

[0018] Figure 8 This is a schematic diagram of the installation of the grating ruler of the present invention;

[0019] Figure 9 (a) (b) (c) (d) are schematic diagrams of polarization modes of piezoelectric ceramic sheets;

[0020] Fig.10 A circuit diagram of connecting the driver and piezoelectric ceramics of the present invention;

[0021] Fig.11 The schematic diagram of the rectifier circuit of the present invention;

[0022] Fig.12 Control flow chart of the present invention. DETAILED DESCRIPTION

[0023] The following is a detailed description in conjunction with the accompanying drawings: As shown in the figure, the base 20 of the double-speed workbench is installed with a vibrator support frame 5 and a lower guide rail 1 by screws, a lower slider 18 is installed on the lower guide rail 1, a lower support plate 17 is connected to the lower guide rail 1, a lower support seat 2 is connected to the lower support plate 17 by screws, an upper support seat 12 is fixed to the upper support plate 14 by a set screw 13, and a clutch device 10 and a guide device 21 are installed on the upper support seat 12 and the lower support seat 2; the clutch device 10 is fixed to the upper support seat 12 and the lower support seat 2 by a positioning plate 3 and a positioning screw 4, and the guide device 21 is fixed to the upper support seat 12 and the lower support seat 2 by a shoulder and a clamp ring; the flexible support plate of the driving device 7 is connected to the vibrator support frame 5 by a screw 6, the driving plate 8 is installed at the tail end of the guide device 21, the inner side is connected to the guide device 21 by bolts, and the outer side is affixed with friction material to contact the driving foot 7-7 of the driving device 7, the upper support seat 12 is connected to the box body 11 by screws, and the box body 11 is connected to the The upper worktable 9 is connected, the lower worktable 16 is installed on the upper part of the lower support seat 2, the upper slider 23 is installed on the upper guide rail 22, the upper slider 23 is connected to the upper support plate 14, the upper slider 23 and the lower slider 18 are both equipped with a locking device 15 and a grating ruler 19, and the guide device 21 is composed of a fixing screw 21-1, a spring pre-tightening screw 21-2, a spring 21-3, a guide shaft 21-4, a clamping ring 21-5, a guide sleeve 21-6, and a gasket 21-7; the driving device 7 The clutch device 10 is connected by a positioning nut A7-1, a piezoelectric ceramic group A 7-2 for bending, a piezoelectric ceramic group B 7-3 for twisting, a positioning sleeve 7-4, a flexible support plate 7-5, an elastic rod 7-6, and a driving foot 7-7, that is, the elastic rod 7-6 of the driving device 7 is equipped with a flexible support plate 7-5, a positioning sleeve 7-4, a piezoelectric ceramic group B 7-3 for twisting, a driving foot 7-7, and a piezoelectric ceramic group A 7-2 for bending, and the end is fixed by a positioning nut A7-1. The clutch device 10 is connected by a positioning nut 10-1, an intermediate sleeve 10-2, a piezoelectric ceramic group 10-3, a positioning plate 10-4, and an elastic rod 10-5, that is, the elastic rod 10-5 of the clutch device 10 is equipped with a positioning plate 10-4, a piezoelectric ceramic group 10-3, and an intermediate sleeve 10-2, and the end is pressed and fixed by a positioning nut 10-1. The locking device 15 is composed of a lock core a15-1, a support plate 15-2, a piezoelectric ceramic group 15-3, a spring 15-4, a gasket 15-5 and a lock core b15-6. That is, the lock core a15-1 of the locking device 15 is connected to the lock core b15-6 and the spring 15-4 is installed, and the piezoelectric ceramic group 15-3, the support plate 15-2 and the gasket 15-5 are installed on the lock core a15-1 and the lock core b15-6.

[0024] In the circuit, X1 is the piezoelectric ceramic group A 7-2 on the drive device 7, and X2 is the piezoelectric ceramic group B 7-3 on the drive device 7; the control chip used by the driver is DSP56F801, and the distance traveled by the workbench is fed back to the driver through the grating ruler 19. The driver automatically adjusts the 4-way PWM output amplitude through its own program to change the vibration amplitude of the piezoelectric ceramic, thereby adjusting the movement speed of the workbench. The device has the advantages of fast response when power is off and self-locking, and when combined with the grating ruler, the movement of the workbench can be controlled with high precision.

[0025] The working process of the workbench is as follows: when the workbench is not working, the clutch device 10 has no electrical signal and is in a retracted state, separated from the driving device 7 without interfering with each other, and the entire workbench is in a stationary state under the control of the locking device 15.

[0026] Single-speed motion: when the upper workbench is working (the lower workbench is stationary), a periodically alternating electrical signal is passed through the piezoelectric ceramic group A 7-2 on the left and right drive devices 7, and the vibrator forms a second-order bending vibration mode. At the same time, a periodically alternating electrical signal is passed through the piezoelectric ceramic group B 7-3, and the vibrator forms a torsional mode. The two are combined into a bending-torsion mode, and then an electrical signal is passed through the piezoelectric ceramic group 10-3 in the clutch device 10 of the upper workbench. The polarized piezoelectric ceramics become piezoelectric vibrators, generate vibrations, and will expand laterally to the left and right sides. At the same time, the piezoelectric ceramic group 15-3 on the locking device 15 contracts upon receiving the electrical signal and loses the locking effect on the track 1. At this time, the driving foot 7-7 of the driving device contacts the driving plate 8, pushing the workbench connected to the clutch device to move forward along the track 1. When the phase of the electrical signal of the piezoelectric ceramic group B 7-3 is changed, the workbench moves backward, and single-speed motion is achieved; similarly, when the lower workbench is working (the upper workbench is stationary), the above process is repeated to achieve single-speed motion.

[0027] Double-speed motion: a periodically alternating electrical signal is passed through the piezoelectric ceramic group A 7-2 and the piezoelectric ceramic group B 7-3 on the driving device 7, and at the same time, an electrical signal is passed through the clutch device 10 and the piezoelectric ceramic group of the locking device 15 of the upper and lower workbenches, so that the clutch device 10 reaches the working position, and the lock cores a15-1 and b15-6 of the locking device shrink at the same time. At this time, the workbench moves at the fastest speed, realizing double-speed motion.

[0028] When the voltage is adjusted, the speed of single-speed movement and double-speed movement will be changed, that is, the working mode of moving different workpieces at different speeds and with different working requirements during the working process of the workbench is realized.

[0029] When the electrical signals of the clutch device 10 and the locking device 15 are cut off, the clutch device 10 contracts and the two sides are no longer in contact. At the same time, the locking device 15 expands and locks. At this time, the workbench stops moving. When the electrical signals of the piezoelectric ceramic group A 7-2 and the piezoelectric ceramic group B 7-3 on the left and right drive devices are cut off, the workbench returns to a non-working state.

[0030] Control flow description: Fig.12 As shown, the power source is 220V AC, which is used to energize the driver and the rectifier (1) respectively. The driver can simultaneously adjust the voltage of the piezoelectric ceramic group A 7-2 and the piezoelectric ceramic group A 7-3. When the piezoelectric ceramic group A 7-2 receives a signal, it generates bending vibration. When the piezoelectric ceramic group B 7-3 receives a signal, it generates torsional vibration. The two work together to form a bending-torsion mode. After the rectifier receives the electrical signal, it converts it into a DC power supply. At the same time, the piezoelectric ceramic group 15-3 and the piezoelectric ceramic group 10-3 (3) are energized. After the piezoelectric ceramic group 15-3 receives the signal, it vibrates and contracts, so the locking device 15 contracts; after the piezoelectric ceramic group 10-3 receives the signal, it vibrates and expands, causing the clutch device 10 to expand; at this time, the driving foot 7-7 contacts the clutch device 10, and friction generates a driving force; therefore, under the joint action of the driving device 7, the clutch device 10, and the locking device 15, the workbench is driven to move; when the phase of the piezoelectric ceramic group B 7-3 is changed (half a cycle), the workbench moves in the opposite direction.

[0031] Piezoelectric ceramics are of uniform specifications and can be purchased or customized directly. However, they differ in application, resulting in bending, torsion, stretching (contraction), which is related to the polarization mode and pasting mode of the piezoelectric ceramic sheet, as shown in Figure 9. For example, a ring-shaped ceramic sheet has two sides divided equally into four equal parts. When opposite voltages are applied to the four sides on the left and right sides of the ceramic sheet, contraction or stretching will occur, as shown in Figure 9 (b); when opposite voltages are applied to the four sides on the upper and lower sides of the ceramic sheet in the axial direction, the ceramic sheet in the positive direction expands and the ceramic sheet in the negative direction contracts, and the two work together to produce bending, as shown in Figure 9 (c); in order to excite torsional vibration of the piezoelectric ceramic sheet in the torsional vibration mode, it is necessary to perform tangential polarization on the piezoelectric ceramic sheet, cut the circular ceramic sheet into several sectors, and then conduct polarization on the two cut sections, as shown in Figure 9 (d), to excite the torsional mode. Excitation frequency 2×10 4 ~3×10 4 Hz, voltage 10~80V.

[0032] The piezoelectric ceramic material can be selected as PZT-4 piezoelectric ceramic, because it has a higher Curie point and phase transition point, can ensure stability over a wide range, and has relatively small dielectric loss, a higher electromechanical coupling coefficient, and good output characteristics.

[0033] The relevant parameters are shown in Table 1 and Table 2:

[0034]

[0035]

Claims

1. A piezoelectric driven dual-speed workbench, characterized in that: The base (20) is installed with a vibrator support frame (5) and a lower guide rail (1) by screws, a lower slider (18) is installed on the lower guide rail (1), a lower support plate (17) is connected to the lower guide rail (1), a lower support seat (2) is connected to the lower support plate (17) by screws, an upper support seat (12) is fixed to an upper support plate (14) by a set screw (13), a clutch device (10) and a guide device (21) are installed on the upper support seat (12) and the lower support seat (2); the clutch device (10) is installed and fixed on the upper support seat (12) and the lower support seat (2) by a first positioning plate (3) and a positioning screw (4), and the guide device (21) is fixed on the upper support seat (12) and the lower support seat (2) by a shaft shoulder and a clamping ring; a second elastic rod (10-5) of the clutch device (10) is sleeved with a second positioning plate (10-4), a first piezoelectric ceramic group (10-5) and a second elastic rod (10-5). -3), an intermediate sleeve (10-2), the end of which is fixed by a positioning nut (10-1); the driving device (7) is connected by a positioning nut A (7-1), a piezoelectric ceramic group A (7-2) for bending, a piezoelectric ceramic group B (7-3) for torsion, a positioning sleeve (7-4), a flexible support plate (7-5), a first elastic rod (7-6), and a driving foot (7-7), that is, the first elastic rod (7-6) of the driving device (7) is equipped with a flexible support plate (7-5), a positioning sleeve (7-4), a piezoelectric ceramic group B (7-3) for torsion, a driving foot (7-7), and a piezoelectric ceramic group A (7-2) for bending, and the end is fixed by a positioning nut A (7-1); the flexible support plate of the driving device (7) is connected to the vibrator support frame (5) by a screw (6), and the driving plate (8) is installed at the tail end of the guide device (21). The inner side is connected to the guide device (21) by bolts, and the outer side is affixed with friction material to contact the driving foot (7-7) of the driving device (7). The upper support seat (12) is connected to the box body (11) by screws, and the box body (11) is connected to the upper work table (9). The lower work table (16) is installed on the upper part of the lower support seat (2). The upper slider (23) is installed on the upper guide rail (22), and the upper slider (23) is connected to the upper support plate (14). The upper slider (23) and the lower slider (18) are both installed with A locking device (15) and a grating ruler (19); in the circuit, X1 is the piezoelectric ceramic group A (7-2) on the driving device (7), and X2 is the piezoelectric ceramic group B (7-3) on the driving device (7); the control chip used by the driver is DSP56F801, and the distance traveled by the workbench is fed back to the driver through the grating ruler (19). The driver automatically adjusts the 4-channel PWM output amplitude through its own program to change the vibration amplitude of the piezoelectric ceramic, so as to adjust the movement speed of the workbench.

2. A piezoelectric driven dual-speed workbench according to claim 1, characterized in that: The lock core a (15-1) and the lock core b (15-6) of the locking device (15) are connected and a locking device spring (15-4) is installed. A second piezoelectric ceramic group (15-3), a support plate (15-2) and a locking device gasket (15-5) are installed on the lock core a (15-1) and the lock core b (15-6).

3. A piezoelectric driven dual-speed workbench according to claim 1, characterized in that: The guide device (21) is connected by a fixing screw (21-1), a spring pre-tightening screw (21-2), a guide device spring (21-3), a guide shaft (21-4), a clamping ring (21-5), a guide sleeve (21-6), and a guide device gasket (21-7).

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