CN114536121B - Flexible clamping mechanism for grinding machining and grinding machining device - Google Patents

Abstract

The invention relates to a flexible clamping mechanism and a grinding device for grinding, including a chuck, the chuck is connected to a fixture plate through a plurality of connecting pieces, and the fixture plate is provided with an opening for a workpiece to pass through. The surface of the hole is fixed with a flexible gasket, and the connector is provided with a first piezoelectric stack on one side of the fixture plate and a second piezoelectric stack on the other side of the fixture plate, and the first piezoelectric stack is pressed by the first pressing member. On one side end surface of the fixture plate, the second piezoelectric stack is pressed against the other side end surface of the fixture plate by the second pressing member. The vibration sensor is installed on the fixture plate, and the clamping mechanism of the present invention has high processing precision.

Description

A flexible clamping mechanism and grinding device for grinding

technical field

The invention relates to the technical field of ultra-precision processing, in particular to a flexible clamping mechanism and processing device for grinding processing.

Background technique

The statements herein merely provide background information related to the present invention and do not necessarily constitute prior art.

According to the ultra-precision grinding processing requirements of large thin-walled rotary ceramic workpieces with a length of 1 meter to 4 meters, the surface accuracy of large thin-walled rotary ceramic workpieces is relatively low due to the influence of factors such as mechanical vibration and fixture clearance during the machining process. Poor, it is difficult to meet the precision requirements of ultra-precision machining. At the same time, there are many common assembly clearances, moments of inertia and other factors, resulting in large deviations in the ultra-precision grinding process of machine tools, which will seriously affect the machining accuracy of the workpiece surface.

The inventors have found that currently, when large-scale thin-walled rotary ceramic workpieces are processed, they are only fixed by chucks at the ends to form a cantilever beam structure, and the vibration of the workpiece is large during rotation, which reduces the machining accuracy. At the same time, in the prior art, there is no Considering the large vibration deviation caused by the gap between the workpiece and the fixture under different grinding conditions, the machining error is relatively large, and the vibration of the tool bar, workpiece vibration, and fixture vibration are not considered, resulting in deflection of the workpiece during rotation. It has an impact on the processing quality of the workpiece.

Contents of the invention

The object of the present invention is to overcome the deficiencies of the prior art, provide a flexible clamping mechanism for grinding, and improve the grinding precision and production efficiency.

To achieve the above object, the present invention adopts the following technical solutions:

In the first aspect, the embodiment of the present invention provides a flexible clamping mechanism for grinding, including a chuck, the chuck is connected to the clamping plate through a plurality of connecting pieces, and the clamping plate is provided with an opening for the workpiece to pass through. A flexible gasket is fixed on the surface of the hole, and the connector is provided with a first piezoelectric stack on one side of the fixture plate and a second piezoelectric stack on the other side of the fixture plate. The first piezoelectric stack passes through the first piezoelectric stack. The clamping part is pressed against one end face of the fixture plate, the second piezoelectric stack is pressed against the other end face of the clamping plate through the second pressing part, and the vibration sensor is installed on the clamping plate.

Optionally, the jig plate is arranged coaxially with the chuck, the connecting member is a connecting rod, and a plurality of connecting rods are evenly distributed along a circle centered on the center of the jig plate.

Optionally, a first pressure sensor is arranged between the first piezoelectric stack and the first pressing member, and a second pressure sensor is arranged between the second piezoelectric stack and the second pressing member.

Optionally, the first pressing part adopts a first compression nut threadedly connected with the connecting part, and the second pressing part adopts a second compressing nut threadedly connected with the connecting part.

Optionally, a plurality of counterweights are also installed on the fixture plate, and the counterweights and vibration sensors are arranged at equal intervals along the same circle centered on the center of the fixture plate, and the weight of the counterweights is equal to the weight of the vibration sensor. equal.

Optionally, a plurality of linear motion driving parts are installed on the fixture plate, and the plurality of linear motion driving parts are equidistantly spaced along the circle centered on the center of the fixture plate. The moving part of the linear driving part is connected with a push plate, and the push plate is provided with A flexible support block matching the shape of the workpiece, the push plate can exert pressure on the workpiece through the flexible support block.

Optionally, the flexible support block is provided with a card slot, the push plate is located inside the card slot, and the push plate is detachably connected to the flexible support block through the card slot.

Optionally, the linear motion driver is rotationally connected to one end of the adjusting rod, and the other end of the adjusting rod is screwed to the positioning block fixed on the fixture plate.

In a second aspect, an embodiment of the present invention provides a grinding device, including the flexible clamping mechanism for grinding described in the first aspect.

Optionally, the cutter bar of the grinding processing device is equipped with a vibration sensor and a tool bar vibration suppression element.

Beneficial effects of the present invention:

1. The clamping device of the present invention, by setting the clamp plate, plays a supporting and centering role on the workpiece, preventing the workpiece from deflecting during the rotation process, and at the same time, the vibration sensor is installed on the clamp plate, which can collect the real-time vibration of the clamp plate Information, considering the randomness of the vibration, when the vibration is too large, the first piezoelectric stack and the second piezoelectric stack are energized, thereby generating a vibration suppression signal through the first piezoelectric stack and the second piezoelectric stack, lowering the fixture plate The vibration amplitude and frequency can avoid large vibration of the fixture and ensure the processing quality.

2. The clamping device of the present invention is provided with a first pressure sensor and a second pressure sensor, which can detect the pressure information received by the clamp plate, so as to detect the axial offset generated by the clamp plate during processing. At this time, the first pressure sensor The electric stack and the second piezoelectric stack are energized, which can compensate the position of the fixture plate, ensure that the fixture body can fit the workpiece through the flexible gasket, and avoid gap errors affecting the machining accuracy, which better solves the lack of corresponding workpieces in the prior art And the combination of fixture vibration suppression and corresponding gap compensation, not only can realize vibration suppression, but also can automatically complete gap compensation and vibration suppression, improving grinding accuracy and production efficiency.

3. The clamping device of the present invention has a linear motion driver, a push plate and a flexible support block, which can buffer the shaking of the workpiece during the clamping process and also play a centering role in the clamping of the workpiece.

4. The clamping device of the present invention, the connector, the linear motion driver, the counterweight and the vibration sensor are all distributed at equal intervals along the circumference, which avoids the instability of the moment of inertia in the working state and ensures the machining accuracy.

5. In the grinding device of the present invention, a vibration motor and a vibration sensor are installed on the cutter bar, which can detect the vibration information of the cutter bar and control the work of the vibration motor, and utilize the vibration motor to suppress the vibration of the cutter bar to ensure machining accuracy.

Description of drawings

The accompanying drawings constituting a part of the present application are used to provide further understanding of the present application, and the schematic embodiments and descriptions of the present application are used to explain the present application and not to limit the present application.

Fig. 1 is a schematic diagram of the overall structure of Embodiment 1 of the present invention;

Fig. 2 is a side view of the overall structure of Embodiment 1 of the present invention;

Figure 3 is a schematic diagram of the assembly of the cushioning cylinder, the flexible support block and the adjusting rod in Embodiment 1 of the present invention;

Among them, 1. Cutter rod, 2. Bolt, 3. Cutter rod vibration suppression element, 4. Vibration sensor, 5. Rotary workpiece, 6. Grinding wheel, 7. Connecting rod, 8. First compression nut, 9 .First pressure sensor, 10. First piezoelectric stack, 11. Positioning block, 12. Adjusting rod, 13. Cushion cylinder, 14. Piston rod, 15. Push plate, 16. Flexible support block, 17. Vibration sensor, 18. Chuck, 19. Connecting rod adjustment nut, 20. Second compression nut, 21. Second pressure sensor, 22. Second piezoelectric stack, 23. Counterweight, 24. Fixture plate, 25. Flexible washer .

Detailed ways

Example 1

This embodiment provides a flexible clamping mechanism for grinding, as shown in Fig. 1-Fig. Can. The chuck 18 and the fixture plate 24 are set at a set distance and coaxially arranged. The chuck 18 and the fixture plate 24 are connected as a whole through a plurality of connecting pieces. The traditional grinding machine only relies on the chuck to fix the workpiece. When the processing size For larger thin-walled rotary ceramic workpieces, the vibration generated by the workpiece is relatively large, and deflection is likely to occur during the rotation process. Therefore, in this embodiment, a fixture plate is provided to support the middle position of the workpiece, which reduces the workpiece’s vibration during rotation. vibrations during the process.

The connecting piece adopts connecting rods 7 , and a plurality of connecting rods 7 are distributed at equal intervals along the circumference with the center of the clamp plate 24 as the center.

On the chuck 18, a plurality of positioning holes are evenly opened along the circumference, and the positioning holes are threaded holes. The adjusting nut 19 is compressed on the surface of the chuck 18 to ensure the connection strength between the connecting rod 7 and the chuck 18 and prevent loosening.

In this embodiment, the chuck 18 is provided with six positioning holes equidistantly distributed along the circumference, of which three positioning holes are used for installing the connecting rods 7, and the three connecting rods 7 are equidistantly distributed along the circumference.

One end of the three connecting rods 7 is fixed to the chuck 18 , and the other end passes through the clamping plate 24 through the mounting holes provided on the clamping plate 24 .

Ring-shaped first piezoelectric stack 10 and second piezoelectric stack 22 are all installed on the three connecting rods 7, and the first piezoelectric stack 10 and the second piezoelectric stack 22 can adopt existing elements. Composed of electric ceramic chips, it can produce telescopic movement along its own axis after electrification.

Take the installation of the first piezoelectric stack 10 and the second piezoelectric stack 22 on one of the connecting rods 7 as an example for illustration:

The first piezoelectric stack 10 is sleeved on the outer periphery of the connecting rod 7 and is located on one side of the fixture plate 24. The connecting rod 7 is connected with a first pressing element, and the first piezoelectric stack is pressed against the fixture by the first pressing element. on this side of the board.

The first compression element adopts the first compression nut 8, which is threadedly connected with the connecting rod 7, and the first compression nut 8 can be rotated to press the first piezoelectric stack 10 against the side of the fixture plate.

A first pressure sensor 9 is disposed between the first compression nut 8 and the first piezoelectric stack 10 , and the first pressure sensor 9 is used to detect pressure information applied to it by the first piezoelectric stack 10 .

The second piezoelectric stack 22 is sleeved on the outer periphery of the connecting rod 7, and is located on the other side of the clamp plate 24. The connecting rod 7 is connected with a second pressing element, and the second piezoelectric stack 22 is pressed by the second pressing element. On this side of the clamp plate 24 .

The second pressing element adopts the second pressing nut 20, which is threadedly connected with the connecting rod 7, and the second pressing nut 20 can be rotated to press the second piezoelectric stack 22 against the side of the fixture plate.

A second pressure sensor 21 is disposed between the second compression nut 20 and the second piezoelectric stack 22 , and the second pressure sensor 21 is used to detect pressure information applied to it by the second piezoelectric stack.

Both the first piezoelectric stack 10 and the second piezoelectric stack 22 are connected to a power supply system, and can be powered by the power supply system.

The fixture plate 24 is provided with a hole, and the hole is arranged coaxially with the fixture plate 24, that is, the hole is set at the center of the fixture plate 24, and the size of the hole matches the size of the rotary workpiece 5 to be processed. The workpiece 5 is fixedly connected with the chuck 18 after passing through the clamping plate 24 .

A flexible gasket 25 is fixed on the hole surface of the hole. In this embodiment, the hole surface of the hole is provided with a slot, and the flexible gasket 25 is detachably fixed on the hole surface of the hole through the slot.

The flexible gasket 25 can be made of rubber material or other flexible materials, which can be set by those skilled in the art according to actual needs.

Multiple flexible gaskets 25 are produced to form a complete set of standardized flexible kits, which can be replaced with corresponding models according to different outer diameter structural parameters of the workpiece, and installed in the slots on the surface of the fixture plate for easy disassembly. At the same time, since the flexible gasket 25 is made of flexible material, it also has the function of absorbing vibration.

The shape of the flexible washer 25 matches the shape of the workpiece to ensure that the flexible washer 25 can better fix the workpiece to be processed.

A vibration sensor 17 is installed on the jig plate 24 for detecting the vibration information of the jig plate 24 .

The vibration sensor 17 can be an existing vibration sensor, and the vibration sensor is installed on the side of the clamp plate 24 away from the chuck 18 .

Because the vibration sensor 17 is installed on the clamp plate 24, the moment of inertia will be unstable in the high-speed rotation process of the clamp plate, so a plurality of counterweights 23 are installed on the side of the vibration sensor installed on the clamp plate to balance the vibration sensor. weight.

The weight of the counterweight 23 is the same as that of the vibration sensor, and the vibration sensor 17 and a plurality of counterweights 23 are installed on the same circle with the center of the clamp plate 24 as the center of the circle, and the vibration sensor 17 and the plurality of counterweights 23 equally spaced distribution.

In this embodiment, two counterweights 23 are provided, and the two counterweights 23 and one vibration sensor 17 are distributed at equal intervals on the same circle centered on the center of the clamp plate 24 .

Fixture plate 24 is also provided with a plurality of positioning blocks on the side for installing vibration sensor 17 and counterweight 23, and a plurality of positioning blocks 11 is arranged at equal intervals along the circumference that takes the center of the clamp plate as a circle. In this embodiment, six positioning blocks are arranged. positioning blocks.

Wherein the three positioning blocks 11 are connected with the linear motion drive parts through the adjustment rod 12, and the linear motion drive parts are distributed at equal intervals along the circumference with the center of the clamp body as the center, and the adjustment rods are arranged along the radial direction of the clamp plate, which can The position of the linear motion driver can be adjusted radially to meet the needs of workpieces of different sizes.

In this embodiment, the linear motion driver adopts a buffer cylinder 13 , and the buffer cylinder 13 has three piston rods 14 .

One end of the adjustment rod 12 is threadedly connected with the positioning block 11, and the other end is rotatably connected with the cylinder body of the buffer cylinder 13 through a bearing. Rotating the adjustment rod 12 can adjust the position of the buffer cylinder 13 along the radial direction of the clamp plate.

The ends of the three piston rods 14 of the buffer cylinder 13 are fixedly connected to the push plate 15, the piston rods 14 can drive the push plate 15 to move radially along the clamp plate 24, the push plate 15 is provided with a flexible support block 16, and the flexible support block 16 The shape matches the shape of the workpiece, the flexible support block 16 can move synchronously with the push plate, and the push plate 15 can apply load to the workpiece through the flexible support block 16.

The push plate 15 is made of metal material with micro-deformation function to meet different workpiece surface structures. The buffer cylinder can adjust the pressure output through the adjustment of the internal air pressure, so that the output force of the three piston rods 14 can be adjusted.

In this embodiment, the flexible support block 16 is provided with a slot, and the push plate is disposed inside the slot and detachably snapped and fixed with the flexible support block 16 through the slot.

Flexible supporting block 16 is made a plurality of, forms a set of perfect parts, can change the model of different flexibility and different radian angles according to different workpiece structural parameters, flexible supporting block is connected with push plate 15 by draw-in groove, convenient dismounting.

By arranging the buffer cylinder 13, the push plate 15 and the flexible support block 16, the shaking generated during the clamping process of the workpiece can be buffered, and at the same time, the clamping of the workpiece can be centered.

In this embodiment, when the vibration sensor 17 collects the vibration information in the process of processing in real time, when the vibration is too large, the first piezoelectric stack 10 and the second piezoelectric stack 22 are energized, so that the first piezoelectric stack 10 and the second piezoelectric stack 22 are energized. The two piezoelectric stacks 22 generate vibration suppression signals, and the first piezoelectric stack 10 and the second piezoelectric stack 22 generate telescopic motions to increase the clamping force on the clamp plate 24, reduce the vibration amplitude and frequency of the clamp plate 24, and avoid clamping Greater vibration ensures the processing quality.

At the same time, the first pressure sensor 9 and the second pressure sensor 21 can collect the pressure values that the first piezoelectric stack 10 and the second piezoelectric stack 22 are subjected to. When the collected pressure values change greatly, it means that the clamping plate 24 has At this time, the first piezoelectric stack 10 and the second piezoelectric stack 22 are energized, and the position compensation of the fixture plate 24 can be performed to ensure that the fixture plate 24 can fit the workpiece through the flexible gasket 25, avoiding the influence of gap errors Machining accuracy, better solve the problem of lack of corresponding workpiece and fixture vibration suppression and corresponding gap compensation combination in the prior art, not only can realize vibration suppression, but also can automatically complete gap compensation and vibration suppression, improving grinding accuracy and Productivity.

In this embodiment, the connecting rod 7, the buffer cylinder 13, the counterweight 23 and the vibration sensors are all distributed at equal intervals along the circumference, which avoids instability of the moment of inertia in the working state and ensures the machining accuracy.

Example 2

This embodiment provides a kind of grinding processing device, is provided with the flexible clamping mechanism that is used for grinding processing described in embodiment 1, also comprises cutter bar 1, and the end of cutter bar is provided with grinding wheel 6, and The rod 1 is fixed with a vibration sensor 4 and a tool bar vibration suppressing element 3 through a bolt 2. The tool bar vibration suppressing element 3 in this embodiment adopts an ultrasonic motor. It can be understood that the vibration suppressing element can also use a miniature vibration motor. Those skilled in the art can make selections according to actual needs.

Parts such as vibration sensor, pressure sensor, power supply system, cutter bar vibration suppressing element 3, buffer cylinder 13 among the present embodiment are all connected with control system, and vibration sensor, pressure sensor can transmit the information that gathers to control system, and control system controls The work of the power supply system, the tool rod vibration suppressing element 3, the buffer cylinder 13 and other components realizes the purpose of automatically suppressing the vibration of the grinding wheel and the fixture and compensating the gap error along with the processing process.

Other structures of the grinding device can adopt the structure of the existing grinding machine, and will not be described in detail here.

The grinding device of this embodiment has reasonable structural design, good operation quality, reliable operation, and high degree of generalization, which fully satisfies the suppression of high-precision grinding vibration during the ultra-precision grinding process of large thin-walled rotary ceramic workpieces. , error compensation system and high-precision control method requirements.

The working method of the grinding device of the present embodiment is:

When performing ultra-precision grinding on large thin-walled rotary parts, it is first necessary to select three matching connecting rods 7 according to the structural appearance parameters of the rotary workpiece 5 and adjust the second Compression nut 20, second pressure sensor 21 and annular second piezoelectric stack 22 installation positions, and ensure that each structure is aligned, and adjust the fixture plate 24 to be parallel to the machine tool datum plane, adjust and install the first compression nut 8, The positions of the first pressure sensor 9 and the ring-shaped first piezoelectric stack 10, adjust the contact force between each ring-shaped piezoelectric stack and the fixture plate; select the flexible gasket 25 model that matches the workpiece structure parameters, and install it on the The fixture plate 24 is perforated and fixed; three sets of flexible support blocks 16 matching the structural parameters of the workpiece are selected and installed on the push plate 15; the end of the rotary workpiece 5 is clamped on the chuck 18 of the machine tool and Determine the position, adjust the position between the flexible gasket 25 on the fixture plate 24 and the rotary body workpiece 5, and ensure that the rotary body workpiece 5 can fit the flexible gasket 25; by adjusting three sets of adjustment rods 12, the flexible support block and the rotary body The workpiece fits perfectly, and the fixture clamping is completed; select the appropriate tool bar 1 and grinding wheel 6, adjust and install the position of the tool bar vibration suppression element 3 on the vibration sensor 4 on the tool bar 1;

When starting the machine tool and starting the machining process, the grinding wheel 6 is in contact with the rotary workpiece 5, and if it is detected that the vibration sensor generates a vibration signal on the tool bar 1, the tool bar vibration suppression element 3 will start to generate a vibration suppression signal, reducing the vibration of the tool bar 1. Vibration amplitude; if a small deviation occurs in the clamp plate 24 detected by the first pressure sensor 9 and the second pressure sensor 21, the second piezoelectric stack 22 of three sets of rings and the first piezoelectric stack 10 work together to simultaneously exert pressure on the clamp The plate 24 performs position compensation to ensure that the fixture plate 24 can fit perfectly with the rotary workpiece 5 through the flexible gasket 25, so as to avoid gap errors affecting the machining accuracy; at the same time, if the vibration sensor on the fixture plate 24 detects that the fixture plate has a large vibration signal, the first piezoelectric stack 10 and the second piezoelectric stack 22 of three sets of rings will start to work, generate corresponding vibration suppression signals, increase the clamping force to the clamping plate 24, reduce the vibration amplitude and frequency of the clamping plate to avoid The workpiece of the rotary body has a large vibration, which improves the processing quality.

Although the specific implementation of the present invention has been described above in conjunction with the accompanying drawings, it does not limit the protection scope of the present invention. Those skilled in the art should understand that on the basis of the technical solution of the present invention, those skilled in the art do not need to pay creative work Various modifications or variations that can be made are still within the protection scope of the present invention.

Claims (8)

1. A flexible clamping mechanism for grinding is characterized by comprising a chuck, wherein the chuck is connected with a clamp plate through a plurality of connecting pieces, the clamp plate is provided with an opening through which a workpiece passes, a flexible gasket is fixed on the hole surface of the opening, the connecting pieces are provided with a first piezoelectric stack positioned on one side of the clamp plate and a second piezoelectric stack positioned on the other side of the clamp plate, the first piezoelectric stack is pressed on one side end face of the clamp plate through a first pressing piece, the second piezoelectric stack is pressed on the other side end face of the clamp plate through a second pressing piece, and the clamp plate is provided with a vibration sensor;

a first pressure sensor is arranged between the first piezoelectric stack and the first pressing piece, and a second pressure sensor is arranged between the second piezoelectric stack and the second pressing piece;

the clamp plate is provided with a plurality of linear motion driving pieces, the linear motion driving pieces are arranged along a circumference facility which is in the center of the clamp plate and is at equal intervals, the moving part of each linear motion driving piece is connected with a push plate, the push plate is provided with a flexible supporting block matched with the shape of a workpiece, and the push plate can apply pressure to the workpiece through the flexible supporting block.

2. The flexible clamping mechanism for grinding operations as defined in claim 1 wherein said clamping plate is disposed coaxially with said chuck, said connecting members being connecting rods, a plurality of connecting rods being evenly distributed along a circumference centered on the center of said clamping plate.

3. A flexible clamping mechanism for grinding operations as defined in claim 1 wherein the first clamping member is a first compression nut threadably engaged with the attachment member and the second clamping member is a second compression nut threadably engaged with the attachment member.

4. The flexible clamping mechanism for grinding of claim 1 wherein the clamp plate further has a plurality of weights mounted thereon, the weights and the vibration sensor being spaced equally along a circle centered on the center of the clamp plate, and the weights being of equal weight to the vibration sensor.

5. The flexible clamping mechanism for grinding operations as defined in claim 1 wherein the flexible support block is provided with a slot, the push plate being located within the slot, the push plate being removably connected to the flexible support block via the slot.

6. The flexible clamping mechanism for grinding operations as defined in claim 1, wherein said linear actuator is rotatably connected to one end of an adjustment rod, and the other end of the adjustment rod is threadedly connected to a positioning block fixed to the clamping plate.

7. An abrasive machining apparatus characterized by being provided with the flexible clamping mechanism for abrasive machining according to any one of claims 1 to 6.

8. The grinding apparatus of claim 7 wherein the tool holder of the grinding apparatus is fitted with a vibration sensor and a tool holder vibration suppression element.

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