Ceramic ball grinding device

Abstract

A ceramic ball grinding device belongs to the technical field of grinding. An existing ceramic ball surface grinding method has the problems that cost is high, grinding preparation time and machining time are long, and fragile materials are damaged. The ceramic ball grinding device comprises a working platform, a rotatable support and three grinding mechanisms, and one grinding mechanism is installed on the working platform and used for supporting and grinding ceramic balls; the rotatable support is positioned above one of the grinding mechanisms and can move up and down and rotate; the other two grinding mechanisms are installed on the rotatable support and symmetrically arranged on the two sides of the grinding ball. A ceramic ball is placed on the grinding mechanisms installed on the working platform, the other two grinding mechanisms move downwards and are attached to the surface of the ceramic ball, the three grinding mechanisms grind the ceramic ball at the same time, and the rotatable support drives the other two grinding mechanisms to rotate so that the surface of the ceramic ball can be ground through revolution and rotation at the same time. The device is mainly used for grinding the surface of the ceramic ball.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of grinding, and particularly relates to a ceramic ball grinding device capable of precisely controlling pressure. BACKGROUND

[0002] The ceramic ball is a spherical part made of ceramic material (such as alumina, aluminum nitride, silicon nitride, etc.) through high-temperature sintering, and has a wide range of applications in the industrial field due to its unique physical and chemical properties such as high-temperature resistance, corrosion resistance, high hardness and wear resistance.

[0003] The ceramic ball is mainly divided into two types according to its use. One is a structural ceramic ball used for mechanical support, such as a bearing rolling element. The other is a functional ceramic ball used for chemical filling, grinding medium, scientific research test, etc. The preparation process of the ceramic ball mainly includes the following steps: powder preparation, molding and sintering, and precision machining. Precision machining is an important link for controlling the surface roughness of the ceramic ball. Controlling the surface roughness of the ceramic ball can improve the friction and wear performance, prolong the fatigue life and ensure the functional reliability, which has an important influence on the performance of the ceramic ball. First, it can reduce friction and wear. When the roughness is too high, the ceramic surface microconvex body intensifies the microscopic cutting of the metal counterpart, accelerating wear. Controlling to the optimal value can increase the real contact area, reduce stress concentration, and reduce the overall wear rate by more than 30%. At the same time, it can improve the service life. Surface roughness is the main origin of fatigue cracks, and controlling the surface roughness can effectively improve the bearing rolling contact fatigue life. It also has an important influence on ensuring its functional performance. In new energy bearings, excessive roughness can cause electrochemical corrosion failure, etc. Therefore, controlling the surface roughness of the ceramic ball is of great significance in many industrial application scenarios. The current methods for controlling the surface roughness of the ceramic ball include V-shaped groove grinding, magnetic fluid polishing, and ultrasonic assisted polishing. The above methods have the problems of high cost, long preparation and processing time, and damage to brittle materials. SUMMARY

[0004] Therefore, the application provides a ceramic ball grinding device which can simultaneously receive the grinding of revolution and rotation on the surface of the ceramic ball, thereby improving the grinding precision.

[0005] To solve the above technical problems, the application adopts the technical scheme of:

[0006] The application relates to a ceramic ball grinding device which comprises a work platform, a rotatable support and three grinding mechanisms, wherein one grinding mechanism is installed on the work platform and used for supporting and grinding ceramic balls; the rotatable support is located above the grinding mechanism and can move up and down and rotate; the other two grinding mechanisms are installed on the rotatable support and symmetrically arranged on two sides of the grinding ball; the ceramic ball is placed on the grinding mechanism installed on the work platform, the other two grinding mechanisms are moved down and attached to the surface of the ceramic ball, the three grinding mechanisms simultaneously grind the ceramic ball, and the rotatable support drives the other two grinding mechanisms to rotate so that the surface of the ceramic ball is simultaneously subjected to revolution and rotation grinding.

[0007] Further, the rotatable support comprises an L-shaped connecting piece, a first stepping motor and a mounting seat, the first stepping motor is fixed on the L-shaped connecting piece, and the mounting seat is arranged below the L-shaped connecting piece and fixedly connected with the motor shaft of the first stepping motor; the other two grinding mechanisms are symmetrically installed on the mounting seat.

[0008] Further, the mounting seat comprises a left side supporting plate, a transverse supporting plate and a right side supporting plate which are sequentially connected, the left side supporting plate and the right side supporting plate are symmetrically arranged with the transverse supporting plate as the center, and the included angle between the left side supporting plate and the transverse supporting plate is greater than 90 degrees, and the included angle between the right side supporting plate and the transverse supporting plate is greater than 90 degrees.

[0009] Further, the grinding mechanism comprises a second stepping motor, a pressure sensor, a piezoelectric ceramic driver, an elastic coupling, a grinding tool and a shell, the motor shell of the second stepping motor is installed on the work platform, the left side supporting plate or the right side supporting plate, the motor shaft of the second stepping motor is connected with the shell, the pressure sensor, the piezoelectric ceramic driver and the elastic coupling are sequentially arranged in the shell and sequentially connected, and the elastic coupling is connected with the grinding tool.

[0010] Further, the grinding tool comprises a upper stepped cylinder and a lower cylinder which are coaxially connected, the upper stepped cylinder is inserted into the lower cylinder and in interference fit with the lower cylinder, and the upper stepped cylinder is filled with grinding paste.

[0011] Further, the longitudinal advancing mechanism is installed on the work platform and connected with the rotatable support, and is used for driving the up and down movement of the rotatable support.

[0012] Further, the longitudinal advancing mechanism comprises a supporting frame, a driving motor, a lead screw shaft, a nut and a sliding block, the supporting frame is vertically installed on the work platform, the driving motor is installed on the top of the supporting frame, the lead screw shaft is rotatably installed on the supporting frame, the nut is screwed on the lead screw shaft and fixedly connected with the sliding block, a sliding groove is formed in the supporting frame along the length direction, and the sliding block can slide in the sliding groove, and the rotatable support is installed on the sliding block.

[0013] Compared with the prior art, the application has the following beneficial effects:

[0014] 1、The application is designed with three grinding mechanisms, based on the principle of generative machining, by accurately controlling the relative movement between the grinding tool and the workpiece, the envelope or trajectory in motion to generate the desired machining surface. It does not depend on the shape of the mold, but through the concept of "motion creates shape", especially suitable for the machining of complex curved surface. One of the grinding mechanisms is used as the bottom support of the ceramic ball, and can also be used to grind the surface of the ceramic ball; the other two grinding mechanisms are symmetrically arranged on both sides of the ceramic ball, which can increase the range of the ceramic ball surface to be ground and speed up the efficiency of the ceramic ball grinding; it can also ensure that the ceramic ball can be evenly stressed during the grinding process, and ensure the quality of the ceramic ball grinding. In addition, the design of the rotatable support makes the two upper grinding mechanisms revolve around the center line of the ceramic ball, and the grinding mechanism can also rotate, that is, the surface of the ceramic ball is simultaneously subjected to the grinding of revolution and rotation, which can ensure the uniformity of the ceramic ball surface grinding and improve the grinding precision.

[0015] 2、The grinding mechanism of the application adopts the design of elastic coupling, which can apply low-pressure elastic pressure to the ceramic ball. Compared with high-pressure grinding of ultrasonic assisted grinding, it can reduce the defects such as pits and snowflake-like peeling of brittle ceramics such as silicon nitride on the surface of the ceramic ball. And through the control of the height of the upper grinding mechanism, the spring compression amount of the elastic coupling can be adjusted, and then the pressure applied by the elastic coupling to the surface of the ceramic ball can be controlled. The lower grinding mechanism does not have an elastic coupling, which can ensure the stable support of the ceramic ball. In addition, the grinding method using grinding paste has lower cost and relatively simple structure compared with the magnetic fluid polishing method, which reduces the difficulty of device use and installation.

[0016] 3、During the grinding process of the ceramic ball, the grinding pressure significantly affects the material removal rate. If the pressure is too large, it will cause the surface roughness to increase, the ceramic surface to scratch, and micro-cracks, etc. If the pressure is too small, it will result in low removal rate and low grinding efficiency. If the pressure is uneven, it will lead to uneven grinding and bring problems such as poor roundness and roughness control. The grinding mechanism of the application adopts the design of piezoelectric ceramic driver, which can adjust the voltage value of the piezoelectric ceramic driver and the compression amount of the spring coupling, so as to effectively control the pressure of the grinding tool. BRIEF DESCRIPTION OF DRAWINGS

[0017] The accompanying drawings are part of the present application and serve to provide a further understanding of the present application.

[0018] Figure 1 is a structural schematic view of a ceramic ball grinding device of the present application.

[0019] Figure 2 is an assembly drawing of three grinding structures and a rotatable support.

[0020] Figure 3A cross-sectional view of the three grinding structures and the rotatable support after assembly.

[0021] BRIEF DESCRIPTION OF DRAWINGS

[0022] Workbench 1;

[0023] Rotatable support 2, L-shaped connecting piece 21, first stepper motor 22, mounting seat 23, left side support plate 231, transverse support plate 232, right side support plate 233;

[0024] Longitudinal advancing mechanism 3, support frame 31, drive motor 32, screw shaft 33, nut 34, sliding block 35;

[0025] Grinding mechanism 4, second stepper motor 41, elastic coupling 42, grinding tool 43, upper stepped cylinder 431, lower cylinder 432, pressure sensor 44, piezoelectric ceramic driver 45. DETAILED DESCRIPTION

[0026] The application will be described in detail below in conjunction with the drawings and specific embodiments.

[0027] The ceramic ball grinding device of the embodiment is mainly used for grinding the surface of a ceramic ball to increase the smoothness of the surface of the ceramic ball. Figure 1 It comprises a workbench 1, a rotatable support 2, a longitudinal advancing mechanism 3 and three grinding mechanisms. The longitudinal advancing mechanism 3 is installed on the workbench 1 and connected with the rotatable support 2, and is used to drive the up-and-down movement of the rotatable support 2. One of the grinding mechanisms is installed on the workbench 1 and below the rotatable support 2, and is used to support and grind the ceramic ball. For the convenience of the following description, this grinding mechanism is referred to as the lower grinding mechanism. The other two grinding mechanisms are installed on the rotatable support 2 and can rotate with the rotatable support 2. The two grinding mechanisms are symmetrically arranged on the two sides of the ceramic ball and are in close contact with the surface of the ceramic ball to grind the surface of the ceramic ball. Similarly, for the convenience of description, the two grinding mechanisms are referred to as the upper grinding mechanisms.

[0028] During the grinding process, the ceramic ball is placed on the lower grinding mechanism 5, and then the rotatable support 2 is driven to move downward by the longitudinal advancing mechanism 3. The two upper grinding mechanisms move downward synchronously with the rotatable support 2, until the two upper grinding mechanisms are close to the ceramic ball. At this time, the ceramic ball is in the middle position of the three grinding mechanisms. The two upper grinding mechanisms are driven to be in close contact with the surface of the ceramic ball, and the three grinding mechanisms are started to grind the surface of the ceramic ball. During the grinding process, the rotatable support 2 rotates the two upper grinding mechanisms to realize the overall grinding of the surface of the ceramic ball, and ensure the accuracy of the grinding of the ceramic ball.

[0029] The three grinding mechanisms are designed, one of which is used as the bottom support seat of the ceramic ball and can grind the surface of the ceramic ball, and the other two grinding mechanisms are symmetrically arranged on the two sides of the ceramic ball, which can increase the range of the ceramic ball surface to be ground and speed up the grinding efficiency of the ceramic ball, and can also ensure that the ceramic ball can be uniformly stressed during grinding and ensure the quality of the ceramic ball grinding. In addition, the design of the rotatable support 2 enables the two upper grinding mechanisms to revolve around the center line a of the ceramic ball, and the grinding mechanisms can also rotate, that is, the surface of the ceramic ball is simultaneously ground by revolution and rotation, which can ensure the uniformity of the ceramic ball surface grinding and improve the grinding precision.

[0030] Referring to Figure 1 The longitudinal advancing mechanism 3 of the embodiment comprises a support frame 31, a driving motor 32, a screw shaft 33, a nut 34 and a sliding block 35. The support frame 31 is vertically installed on the working platform 1, the driving motor 32 is installed on the top of the support frame 31, and the screw shaft 33 is arranged along the length direction of the support frame 31 and is rotationally installed on the support frame 31. The nut 34 is screwed on the screw shaft 33 and is fixedly connected with the sliding block 35. The support frame 31 is provided with a sliding groove along the length direction, and the sliding block 35 can slide in the sliding groove. The rotatable support 2 is installed on the sliding block 35. The driving motor 32 drives the screw shaft 33 to rotate, and the nut 34 moves along the axis of the screw shaft 33 under the limitation of the sliding block 35 and the sliding groove, thereby driving the sliding block 35 and the rotatable support 2 to move up and down, so as to adjust the distance between the two upper grinding mechanisms and the ceramic ball.

[0031] Referring to Figure 1 and Figure 2 The rotatable support 2 of the embodiment comprises an L-shaped connecting piece 21, a first stepping motor 22 and a mounting seat 23. The vertical plate of the L-shaped connecting piece 21 is fixed on the sliding block 35, the motor shell of the first stepping motor 22 is fixed on the horizontal plate of the L-shaped connecting piece 21, and the mounting seat 23 is arranged below the L-shaped connecting piece 21 and is fixedly connected with the motor shaft of the first stepping motor 22. When the first stepping motor 22 drives the mounting seat 23 to rotate, the mounting seat 23 drives the two upper grinding mechanisms thereon to rotate, thereby realizing the revolution of the two upper grinding mechanisms.

[0032] The mounting seat 23 of the embodiment is a bracket with a trapezoidal cross section. Specifically, it comprises a left support plate 231, a transverse support plate 232 and a right support plate 233 connected in sequence, and the left and right support plates 231 and 233 are arranged on the left and right sides of the ceramic ball respectively. The included angle between the left support plate 231 and the transverse support plate 232 is 120 degrees, and the included angle between the right support plate 233 and the transverse support plate 232 is also 120 degrees. After the two upper grinding mechanisms are installed on the left and right support plates 231 and 233 respectively, they can be arranged perpendicular to the surfaces of the left and right support plates 231 and 233, and the grinding tools of the two upper grinding mechanisms can extend to the position of the surface of the ceramic ball and generate a normal pressure on the surface of the ceramic ball.

[0033] Referring to Figure 3 The grinding mechanism 4 of the embodiment comprises a second stepper motor 41, a pressure sensor 44, a piezoelectric ceramic driver 45, an elastic coupling 42, a grinding tool 43 and a housing 46. The motor housing of the second stepper motor 41 is installed on the workbench 1, the left support plate 231 or the right support plate 233. The motor shaft of the second stepper motor 41 is connected with the housing 46. The pressure sensor 44, the piezoelectric ceramic driver 45 and the elastic coupling 42 are arranged in the housing 46 in sequence and are connected in sequence. The elastic coupling 42 is connected with the grinding tool 43.

[0034] The grinding pressure can be obtained in real time by the pressure sensor 44. The pressure sensor transmits the pressure value back to the terminal. The force value of the pressure sensor is read by the Arduino program, and is compared with the expected pressure value. According to the deviation value, the signal input of the high-voltage amplifier is controlled, the voltage value of the piezoelectric ceramic driver 45 is adjusted to control the elongation of the piezoelectric ceramic driver 45, and the compression amount of the spring coupling 42 is controlled to further precisely control the grinding pressure of the ceramic ball, so as to realize the precise grinding of the surface of the ceramic ball.

[0035] In combination with Figure 3The grinding tool 43 of the embodiment comprises a coaxially connected upper stepped cylinder 431 and a lower cylinder 432, the upper stepped cylinder 431 is inserted into the lower cylinder 432 and is in interference fit with the lower cylinder 432. The lower cylinder 432 is connected with the motor shaft of the elastic coupling 42 or the second stepping motor 41 through a screw. In use, the upper stepped cylinder 431 is filled with grinding paste, and the grinding tool 43 grinds the surface of the ceramic ball through the grinding paste. In some embodiments, the upper stepped cylinder 431 and the lower cylinder 432 are made of polytetrafluoroethylene. The outer diameter of the lower stepped cylinder is 20 mm, and the inner diameter is 13 mm. The maximum outer diameter of the upper stepped cylinder 431 is 13 mm, and the minimum outer diameter is 9 mm. The inner diameter of the upper stepped cylinder 431 is 7 mm. By changing the size of the upper stepped cylinder 431 and the height of the upper grinding mechanism, the grinding of ceramic balls with a diameter of less than 13 mm can be realized.

[0036] During grinding, the upper stepped cylinder 431 of the grinding tool 43 is filled with grinding paste, and then the stepping motors of the three grinding mechanisms are started at the same time. The second stepping motor 41 drives the grinding tool 43 to rotate through the elastic coupling 42, and the grinding paste in the grinding tool 43 grinds the surface of the ceramic ball. As the ceramic ball is ground, the elastic coupling 42 can push the grinding tool 43 to move to the side of the ceramic ball, so that the grinding paste can always contact the surface of the ceramic ball to grind it.

[0037] The upper grinding mechanism of the embodiment adopts the design of the elastic coupling 42, which can apply low-pressure elastic pressure to the ceramic ball. Compared with high-pressure grinding of ultrasonic-assisted grinding, the defects such as pits and snowflake-shaped peeling of brittle ceramics such as silicon nitride on the surface of the ceramic ball can be reduced. Moreover, by controlling the height of the upper grinding mechanism, the spring compression amount of the elastic coupling 42 can be adjusted, and then the pressure applied by the elastic coupling 42 to the surface of the ceramic ball can be controlled. The lower grinding mechanism 5 is not provided with the elastic coupling 42, which can ensure the stable support of the ceramic ball. In addition, the grinding method using grinding paste has lower cost and relatively simple structure compared with the magnetic fluid polishing method, which reduces the difficulty of using and installing the device.

[0038] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, and are not intended to limit the protection scope of the present application. Although the present application has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present application can be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present application.

Claims

1. A ceramic ball grinding device, characterized in that, The device includes a working platform, a rotatable support, and three grinding mechanisms. One grinding mechanism is mounted on the working platform to support and grind ceramic balls. The rotatable support is located above the one grinding mechanism and can move up and down and rotate. The other two grinding mechanisms are mounted on the rotatable support and symmetrically arranged on both sides of the grinding ball. The ceramic ball is placed on the one grinding mechanism mounted on the working platform, and the other two grinding mechanisms move down and fit against the surface of the ceramic ball. The three grinding mechanisms grind the ceramic ball simultaneously. The rotatable support drives the other two grinding mechanisms to rotate so that the surface of the ceramic ball is simultaneously ground by both revolution and rotation.

2. The ceramic ball grinding device according to claim 1, characterized in that, The rotatable support includes an L-shaped connector, a first stepper motor, and a mounting base. The first stepper motor is fixedly mounted on the L-shaped connector, and the mounting base is located below the L-shaped connector and fixedly connected to the motor shaft of the first stepper motor. The other two grinding mechanisms are symmetrically mounted on the mounting base.

3. The ceramic ball grinding device according to claim 2, characterized in that, The mounting base includes a left support plate, a horizontal support plate, and a right support plate connected in sequence. The left and right support plates are symmetrically arranged with the horizontal support plate as the center, and the included angle between the left support plate and the horizontal support plate is controlled at 120 degrees, and the included angle between the right support plate and the horizontal support plate is controlled at 120 degrees.

4. The ceramic ball grinding device according to claim 3, characterized in that, The grinding mechanism includes a second stepper motor, a pressure sensor, a piezoelectric ceramic driver, a flexible coupling, a grinding wheel, and a housing. The motor housing of the second stepper motor is mounted on the work platform, the left support plate, or the right support plate. The motor shaft of the second stepper motor is connected to the housing. The pressure sensor, the piezoelectric ceramic driver, and the flexible coupling are sequentially arranged inside the housing and connected in sequence. The flexible coupling is connected to the grinding wheel.

5. A ceramic ball grinding device according to claim 4, characterized in that, The abrasive includes an upper stepped cylinder and a lower cylinder coaxially connected. The upper stepped cylinder is inserted into the lower cylinder and is interference-fitted with the lower cylinder. The upper stepped cylinder is filled with abrasive paste.

6. The ceramic ball grinding device according to claim 1, characterized in that, It also includes a longitudinal propulsion mechanism, which is installed on the working platform and connected to the rotatable support to drive the rotatable support to move up and down.

7. A ceramic ball grinding device according to claim 6, characterized in that, The longitudinal propulsion mechanism includes a support frame, a drive motor, a lead screw, a nut, and a slider. The support frame is vertically mounted on the work platform, the drive motor is mounted on the top of the support frame, the lead screw is rotatably mounted on the support frame, the nut is screwed onto the lead screw and fixedly connected to the slider, and a groove is provided on the support frame along its length, allowing the slider to slide within the groove. A rotatable support is mounted on the slider.

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