A CT tube ball bearing high-temperature clearance measuring device and a measuring method thereof

Abstract

This invention relates to the field of bearing clearance measurement technology, and in particular to a high-temperature clearance measuring device and method for ball bearings in CT X-ray tubes. It includes a positioning base with clamping holes for clamping ball bearing assemblies; a heating module on one side of the positioning base for heating the ball bearing assembly; and a load module and a measuring module on the left and right sides of the positioning base, respectively. The load module applies radial or axial loads to one end of the ball bearing assembly. This invention can accurately measure the radial and axial clearance of ball bearing assemblies, ensuring the quality of CT X-ray tubes and achieving a detection capability from scratch. This invention can simulate the operating temperature of CT X-ray tubes, providing results closer to actual operating conditions, and can effectively screen out bearings with unacceptable clearance under hot conditions.

Description

Technical Field

[0001] This invention relates to the field of bearing clearance measurement technology, and in particular to a high-temperature clearance measuring device and method for CT ball bearings. Background Technology

[0002] The CT tube is the core component of a computed tomography (CT) scanner, with ball bearings inside supporting a high-speed rotating anode target disk. The bearing clearance (radial clearance and axial clearance) directly affects the tube's vibration, noise, and service life.

[0003] Currently, CT tube manufacturers generally lack the capability to inspect bearing clearance upon arrival at the factory, relying entirely on factory data provided by bearing manufacturers. However, bearing manufacturers typically perform measurements at room temperature, while the actual operating temperature of a CT tube can reach 400°C. Due to the difference in thermal expansion coefficients between the bearing material (such as bearing steel and balls) and the bearing housing material, there is a significant difference between the room temperature clearance and the clearance at the actual operating temperature. If the hot clearance is too small, it may cause the bearing to seize; if it is too large, it will cause excessive vibration, increased noise, or even premature failure. Summary of the Invention

[0004] This application addresses the shortcomings of existing production technologies by providing a high-temperature clearance measuring device and method for CT tube ball bearings. This device can simulate the working temperature of the CT tube and accurately measure the radial and axial clearance of the ball bearing assembly, ensuring the quality of the CT tube.

[0005] The technical solution adopted in this invention is as follows: A high-temperature clearance measuring device for ball bearings in a CT X-ray tube includes a positioning base with clamping holes for clamping ball bearing assemblies. A heating module is located on one side of the positioning base to heat the ball bearing assembly. A load module and a measuring module are located on the left and right sides of the positioning base, respectively. The load module applies a radial or axial load to one end of the ball bearing assembly. The measuring module includes a measuring support with axial mounting holes along the axial direction of the ball bearing assembly to be measured. An axial measuring element is installed in the axial mounting holes, with its measuring end facing one end face of the ball bearing assembly. A first radial mounting hole and a second radial mounting hole are located on the measuring support along the radial direction of the ball bearing assembly. A first radial measuring element is installed in the first radial mounting hole, and a second radial measuring element is installed in the second radial mounting hole. The measuring ends of the first and second radial measuring elements face the side faces of the ball bearing assembly, and the first and second radial measuring elements are symmetrically distributed about the central axis of the ball bearing assembly.

[0006] Furthermore, multiple threaded holes are provided on the side wall of the positioning base. These multiple threaded holes are equidistantly distributed on the same circumference. A positioning screw is connected to each of the multiple threaded holes, and the positioning end of the positioning screw can pass through the threaded hole and extend into the clamping hole.

[0007] Furthermore, the heating module includes a heating base with a heating hole at its center. A heating element is fixed to the inner wall of the heating hole, and the heating element is capable of heating the ball bearing assembly.

[0008] Furthermore, the heating element is a heating coil, which is electrically connected to the heating power supply. A thermostat is installed on one side of the heating element, and the thermostat is electrically connected to the heating power supply.

[0009] Furthermore, the outer surfaces of the axial measuring element, the first radial measuring element, and the second radial measuring element are connected by two locking nuts via threads, thereby locking the positions of the axial measuring element, the first radial measuring element, and the second radial measuring element onto the measuring support.

[0010] Furthermore, the axial measuring element, the first radial measuring element, and the second radial measuring element are electrically connected to the displacement monitor, which in turn is electrically connected to the host computer.

[0011] Furthermore, the load module includes a load bracket, the lower part of which is connected to one end of a ball bearing assembly by bolts, multiple axial hooks are provided on the lower side of the load bracket, a load mounting cavity is provided on the upper part of the load bracket, a weight is placed in the load mounting cavity, and multiple radial hooks are provided on the upper part of the load bracket.

[0012] A method for measuring the high-temperature clearance of ball bearings in a CT X-ray tube includes the following steps: Installation: Insert the ball bearing assembly to be tested directly into the mounting hole of the positioning base and tighten it with positioning screws; Heating: Activate the heating module to heat the ball bearing assembly to be tested to the preset temperature T, and then keep it at that temperature for 10 to 30 minutes; Radial clearance measurement: Apply radial force Fr1 to the ball bearing assembly in the first radial direction, and record the readings of the first radial measuring element Sr11 and the second radial measuring element Sr21; remove Fr1, apply radial force Fr2 in the second radial direction opposite to the first radial direction, and record Sr12 and Sr22; calculate the radial clearance according to the formula: Gr = |(Sr11 - Sr12) -(Sr21 - Sr22)| / 2; Axial clearance measurement: Apply a first axial force Fa1 to the ball bearing assembly and record the axial measuring element reading Sa1; remove Fa1 and apply a second axial force Fa2 in the opposite direction and record Sa2; calculate the axial clearance: Ga = |Sa1 - Sa2|; Data storage: The measured temperature T, radial clearance Gr, axial clearance Ga, measurement time, and other information are saved to the host computer.

[0013] The beneficial effects of this invention are as follows: This invention can accurately measure the radial and axial clearance of ball bearing assemblies, ensuring the quality of CT tubes and achieving detection capabilities from scratch. This invention can simulate the working temperature of CT tubes, and the results are closer to the actual working conditions, which can effectively screen out bearings with unqualified radial clearance under hot conditions. This invention uses an eddy current sensor, combined with radial-diameter bidirectional measurement and differential calculation, to automatically eliminate installation eccentricity errors and ensure measurement accuracy. Attached Figure Description

[0014] Figure 1 This is a perspective view of the present invention.

[0015] Figure 2 This is a first-view structural diagram of the present invention.

[0016] Figure 3 This is a second-view structural diagram of the present invention.

[0017] Figure 4 This is a half-sectional view of the ball bearing assembly clamping according to the present invention.

[0018] The components include: 1. Positioning base; 2. Positioning screw; 3. Heating base; 4. Heating element; 5. Heating power supply; 6. Measuring support; 7. Axial measuring element; 8. First radial measuring element; 9. Second radial measuring element; 10. Displacement monitor; 11. Host computer; 12. Temperature controller; 13. Load bracket; 14. Weight; 15. Radial hook; 16. Axial hook; 17. Ball bearing assembly. Detailed Implementation

[0019] The specific embodiments of the present invention will now be described with reference to the accompanying drawings.

[0020] like Figure 2 and Figure 3 As shown, a CT ball bearing high-temperature clearance measuring device includes a positioning base 1, which is used to position and clamp the ball bearing assembly 17 to be measured. The positioning base 1 has an axially penetrating clamping hole on its upper part, which can clamp the ball bearing assembly 17 for bearing clearance measurement.

[0021] like Figure 2 , Figure 3 and Figure 4As shown, three threaded holes are provided on the side wall of the positioning base 1. The three threaded holes are equidistantly distributed on the same circumference. A positioning screw 2 is connected to each of the three threaded holes. The positioning end of the positioning screw 2 can pass through the threaded hole and extend into the clamping hole. A positioning groove is provided on the side wall of the ball bearing assembly 17 along the circumferential direction. The positioning end of the positioning screw 2 can extend into the positioning groove of the ball bearing assembly 17 to realize the positioning and clamping of the ball bearing assembly 17 on the positioning base 1.

[0022] like Figure 2 and Figure 3 As shown, a heating module is provided on one side of the positioning base 1. The heating module includes a heating base 3. The heating base 3 has an axially penetrating heating hole at its center. A heating element 4 is fixed on the inner wall of the heating hole. The ball bearing assembly 17, after being clamped, extends into the heating hole. When the heating element 4 is working, it can heat the ball bearing assembly 17.

[0023] like Figure 1 As shown, the heating element 4 can be a heating coil, which is electrically connected to the heating power supply 5. A temperature controller 12 is also provided on one side of the heating element 4. The temperature controller 12 is electrically connected to the heating power supply 5. The heating problem can be precisely controlled by the temperature controller 12, which can heat the ball bearing to any temperature in the range of room temperature to 300℃, with a temperature control accuracy of ±2℃.

[0024] like Figure 2 and Figure 3 As shown, a load module and a measurement module are respectively installed on the left and right sides of the positioning base 1. The load module can apply radial or axial load to one end of the positioned ball bearing. When a load is applied, the measurement module can measure the radial or axial clearance of the other end of the positioned ball bearing assembly.

[0025] like Figure 2 and Figure 3 As shown, the measurement module includes a measurement support 6. An axial mounting hole is provided on the measurement support 6 along the axial direction of the ball bearing assembly to be measured. An axial measuring element 7 is installed within the axial mounting hole, with its measuring end facing one side of the ball bearing assembly to be measured. A first radial mounting hole and a second radial mounting hole are respectively provided on the measurement support 6 along the radial direction of the ball bearing assembly to be measured. A first radial measuring element 8 is installed within the first radial mounting hole, and a second radial measuring element 9 is installed within the second radial mounting hole. The measuring ends of the first radial measuring element 8 and the second radial measuring element 9 face the side of the ball bearing assembly to be measured, and the first radial measuring element 8 and the second radial measuring element 9 are symmetrically distributed about the central axis of the ball bearing assembly to be measured.

[0026] The axial measuring element 7, the first radial measuring element 8, and the second radial measuring element 9 are all eddy current displacement sensors. The outer surfaces of the axial measuring element 7, the first radial measuring element 8, and the second radial measuring element 9 are connected by two locking nuts through threads. The two locking nuts lock the positions of the axial measuring element 7, the first radial measuring element 8, and the second radial measuring element 9 onto the measuring support 6.

[0027] like Figure 1 As shown, the axial measuring element 7, the first radial measuring element 8, and the second radial measuring element 9 are electrically connected to the displacement monitor 10, which is in turn electrically connected to the host computer 11. The displacement monitor 10 can transmit the measured radial and axial clearance data of the ball bearing assembly to the host computer 11 for storage.

[0028] like Figure 2 , Figure 3 and Figure 4 As shown, the load module includes a load bracket 13. The lower part of the load bracket 13 is bolted to one end of the ball bearing assembly. Multiple axial hooks 16 are provided on the lower side of the load bracket 13. An axial load needs to be applied when measuring the bearing's axial clearance. A drive element is connected to the multiple axial hooks 16, allowing the drive element to axially pull the ball bearing assembly and move it axially. A load mounting cavity is provided on the upper part of the load bracket 13, and a weight is placed inside the load mounting cavity. Radial pressure is applied to the ball bearing assembly by the weight. Multiple radial hooks 15 are provided on the upper part of the load bracket 13. A radial load needs to be applied when measuring the bearing's radial clearance. A drive element is connected to the multiple axial hooks 16, allowing the drive element to apply radial tension to the ball bearing assembly.

[0029] A method for measuring the high-temperature clearance of ball bearings in a CT X-ray tube includes the following steps: Installation: Insert the ball bearing assembly 17 to be tested directly into the mounting hole of the positioning base 1 and tighten it with the positioning screw 2.

[0030] Heating: Start the heating module to heat the ball bearing assembly 17 to be tested to a preset temperature T, which ranges from 0℃ to 500℃, and then keep it at that temperature for 10 to 30 minutes.

[0031] Radial clearance measurement: Apply radial force Fr1 to the ball bearing assembly 17 in the first radial direction, and record the readings of the first radial measuring element 8 Sr11 and the second radial measuring element Sr21; remove Fr1, apply radial force Fr2 in the second radial direction opposite to the first radial direction, and record Sr12 and Sr22; calculate the radial clearance according to the formula: Gr = |(Sr11 -Sr12) - (Sr21 - Sr22)| / 2.

[0032] Axial clearance measurement: Apply a first axial force Fa1 to the ball bearing assembly 17 and record the reading Sa1 of the axial measuring element 7; remove Fa1 and apply a second axial force Fa2 in the opposite direction and record Sa2; calculate the axial clearance: Ga = |Sa1 - Sa2|.

[0033] Data storage: The measured temperature T, radial clearance Gr, axial clearance Ga, measurement time, and other information are saved to the host computer.

[0034] This invention can accurately measure the radial and axial clearance of ball bearing assemblies, ensuring the quality of CT tubes and achieving detection capabilities from scratch. This invention can simulate the working temperature of CT tubes, and the results are closer to the actual working conditions, which can effectively screen out bearings with unqualified radial clearance under hot conditions. This invention uses an eddy current sensor, combined with radial-diameter bidirectional measurement and differential calculation, to automatically eliminate installation eccentricity errors and ensure measurement accuracy.

Claims

1. A CT tube ball bearing high temperature play measuring device comprising a positioning base (1), characterized in that: The positioning base (1) is provided with a clamping hole, which can clamp the ball bearing assembly (17); a heating module is provided on one side of the positioning base (1), which can heat the ball bearing assembly (17); a load module and a measuring module are respectively provided on the left and right sides of the positioning base (1), the load module can apply a radial load or an axial load to one end of the ball bearing assembly (17), the measuring module includes a measuring support (6), the measuring support (6) is provided with an axial mounting hole along the axial direction of the ball bearing assembly (17) to be measured, and an axial measuring element (7) is provided in the axial mounting hole. The measuring end of the element (7) faces one side of the ball bearing assembly (17). The measuring support (6) is provided with a first radial mounting hole and a second radial mounting hole along the radial direction of the ball bearing assembly (17). The first radial measuring element (8) is provided in the first radial mounting hole, and the second radial measuring element (9) is provided in the second radial mounting hole. The measuring ends of the first radial measuring element (8) and the second radial measuring element (9) face the side of the ball bearing assembly (17) respectively, and the first radial measuring element (8) and the second radial measuring element (9) are symmetrically distributed on the left and right with the central axis of the ball bearing assembly (17) as the center.

2. A CT tube ball bearing high temperature end play measuring device as defined in claim 1, wherein: The positioning base (1) has multiple threaded holes on its side wall. The multiple threaded holes are equidistantly distributed on the same circumference. Each of the multiple threaded holes is connected to a positioning screw (2). The positioning end of the positioning screw (2) can pass through the threaded hole and extend into the clamping hole.

3. A CT tube ball bearing high temperature end play measuring device as defined in claim 1 wherein: The heating module includes a heating base (3), a heating hole is provided in the center of the heating base (3), and a heating element (4) is fixed on the inner wall of the heating hole.

4. A CT tube ball bearing high temperature end play measuring device as defined in claim 3 wherein: The heating element (4) is a heating coil, which is electrically connected to the heating power supply (5). A temperature controller (12) is provided on one side of the heating element (4), and the temperature controller (12) and the heating power supply (5) are electrically connected.

5. The high-temperature clearance measuring device for ball bearings in a CT X-ray tube as described in claim 1, characterized in that: The outer surfaces of the axial measuring element (7), the first radial measuring element (8), and the second radial measuring element (9) are connected by two locking nuts through threads, and the positions of the axial measuring element (7), the first radial measuring element (8), and the second radial measuring element (9) are locked on the measuring support (6) by the two locking nuts.

6. The high-temperature clearance measuring device for CT X-ray tube ball bearings as described in claim 5, characterized in that: The axial measuring element (7), the first radial measuring element (8), and the second radial measuring element (9) are electrically connected to the displacement monitor (10), and the displacement monitor (10) is electrically connected to the host computer (11).

7. The high-temperature clearance measuring device for CT tube ball bearings as described in claim 1, characterized in that: The load module includes a load bracket (13), the lower part of which is connected to one end of a ball bearing assembly (17) by bolts. Multiple axial hooks (16) are provided on the lower side of the load bracket (13), a load mounting cavity is provided on the upper part of the load bracket (13), a weight is provided in the load mounting cavity, and multiple radial hooks (15) are provided on the upper part of the load bracket (13).

8. A method for measuring the high-temperature clearance of ball bearings in a CT X-ray tube, characterized in that, Includes the following steps: Installation: The ball bearing assembly (17) to be tested is directly installed into the mounting hole of the positioning base (1) and locked with the positioning screw (2); Heating: Start the heating module to heat the ball bearing assembly (17) to be tested to the preset temperature T, and then keep it at that temperature for 10 to 30 minutes; Radial clearance measurement: Apply radial force Fr1 to the ball bearing assembly (17) in the first radial direction, record the reading Sr11 of the first radial measuring element (8) and the reading Sr21 of the second radial measuring element; remove Fr1, apply radial force Fr2 in the second radial direction opposite to the first radial direction, and record Sr12 and Sr22; calculate the radial clearance according to the formula: Gr = |(Sr11 -Sr12) - (Sr21 - Sr22)| / 2; Axial clearance measurement: Apply a first axial force Fa1 to the ball bearing assembly (17) and record the reading Sa1 of the axial measuring element (7); remove Fa1 and apply a second axial force Fa2 in the opposite direction and record Sa2; calculate the axial clearance: Ga = |Sa1 - Sa2|; Data storage: The measured temperature T, radial clearance Gr, axial clearance Ga, measurement time, and other information are saved to the host computer.

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