A sample fixing device for detecting thermal expansion coefficient of carbon brush
Patent Information
- Application Number
- CN202620079220.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2026-01-21
- Publication Date
- 2026-10-13
- Estimated Expiration
- 2036-01-21
AI Technical Summary
然而，传统固定装置中碳刷样品多为静止放置，与加热源的相对位置固定，导致样品靠近加热源的一侧与远离加热源的一侧存在明显温度梯度，受热不均匀，进而引发样品局部过度膨胀或膨胀不充分，造成热膨胀系数检测结果出现较大偏差，无法真实反映碳刷的热变形特性
1、该碳刷热膨胀系数检测用样品固定装置，通过设置由角铁、丝杆、转轮及支撑板构成的夹持组件，实现对不同尺寸规格碳刷样品的稳定夹持，有效避免碳刷样品在检测过程中发生位移或偏转，通过电机驱动圆台转动，能够带动碳刷样品进行周向旋转，配合侧板上的加热板实现均匀受热，避免碳刷样品局部受热不均导致的检测数据偏差问题。
Smart Images
Figure CN224847157U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of carbon brush testing technology, specifically a sample fixing device for testing the thermal expansion coefficient of carbon brushes. Background Technology
[0002] As a core, easily damaged component in electrical equipment such as motors, generators, and rectifiers, carbon brushes directly determine the operational stability and service life of the equipment. During operation, carbon brushes generate a significant amount of heat due to friction. Temperature changes trigger thermal expansion of the carbon brush itself. The coefficient of thermal expansion, a key parameter characterizing the thermal deformation of carbon brushes, is crucial for equipment structural design, clearance design, and predictive fault prediction. Therefore, accurate measurement of the coefficient of thermal expansion of carbon brushes is of great significance for the research and development and production of electrical equipment.
[0003] In the process of testing the coefficient of thermal expansion of carbon brushes, the sample fixing device is a core supporting equipment to ensure the accuracy of the test. It needs to achieve stable clamping of the carbon brush sample, uniform heating, and convenient detection of the expansion amount. However, in traditional fixing devices, the carbon brush sample is mostly placed statically with a fixed relative position to the heating source. This results in a significant temperature gradient between the side of the sample closer to the heating source and the side farther away from the heating source, leading to uneven heating. This, in turn, causes local over-expansion or insufficient expansion of the sample, resulting in a large deviation in the coefficient of thermal expansion test results, which cannot truly reflect the thermal deformation characteristics of the carbon brush. Utility Model Content
[0004] The purpose of this invention is to provide a sample fixing device for detecting the thermal expansion coefficient of carbon brushes, so as to solve the problems mentioned in the background art.
[0005] To achieve the above objectives, this utility model provides the following technical solution: a sample fixing device for detecting the thermal expansion coefficient of a carbon brush, comprising a fixing frame, a side plate fixedly connected to the end of the fixing frame, a heating plate fixedly installed on the side wall of the side plate, a movable seat slidably connected to the inner wall of the fixing frame, a bearing plate fixedly connected to the surface of the movable seat, a frustum rotatably connected to the surface of the bearing plate, a placement groove formed on the surface of the frustum, a clamping assembly provided inside the placement groove, the clamping assembly comprising an angle iron, the angle iron fitting against the inner wall of the placement groove, a lead screw rotatably connected to the outer wall of the angle iron, a wheel fixedly connected to the end of the lead screw, a support plate threadedly connected to the outer wall of the lead screw, and the support plate fixedly connected to the surface of the placement groove.
[0006] Preferably, a detection component is provided on the side of the support plate. The detection component includes an L-plate, which is fixedly connected to the side wall of the support plate. The side wall of the L-plate has a through hole, and a slide rod is slidably connected in the through hole. One end of the slide rod is fixedly connected to a contact plate, and the other end of the slide rod is fixedly connected to a protrusion. The contact plate and the support plate are elastically connected by a spring.
[0007] Preferably, a motor is fixedly connected to the surface of the movable seat, and the output shaft of the motor passes through the surface of the movable seat and the bearing plate and is fixedly connected to the bottom surface of the frustum. Two sets of through holes are opened on the side wall of the movable seat, and a guide rod is slidably connected in one set of the through holes. The guide rod is fixedly connected to the inner wall of the fixed frame.
[0008] Preferably, another set of the through holes is threaded with a threaded rod, which passes through and is rotatably connected to the inner wall of the fixed frame. One end of the threaded rod is rotatably connected to the inner wall of the fixed frame, and the other end of the threaded rod is fixedly connected to a crank handle.
[0009] Preferably, a scale is provided on the surface of the slide bar.
[0010] Preferably, the bottom surface of the fixed frame is fixedly connected with four sets of symmetrically arranged support legs.
[0011] Compared with the prior art, this utility model provides a sample fixing device for detecting the thermal expansion coefficient of carbon brushes, which has the following beneficial effects: 1. This sample fixing device for carbon brush thermal expansion coefficient testing uses a clamping assembly consisting of angle iron, lead screw, rotating wheel and support plate to stably clamp carbon brush samples of different sizes and specifications, effectively preventing displacement or deflection of the carbon brush sample during testing. The rotating frustum driven by the motor can drive the carbon brush sample to rotate circumferentially, and the heating plate on the side plate can achieve uniform heating, avoiding the problem of test data deviation caused by uneven heating of the carbon brush sample.
[0012] 2. This sample fixing device for detecting the thermal expansion coefficient of carbon brushes uses a detection assembly consisting of an L-plate, a sliding rod, a contact plate, a spring, and a scale. The spring's elastic support ensures the contact plate remains in contact with the carbon brush sample surface. When the carbon brush sample expands due to heat, it pushes the sliding rod to move. The operator can directly read the displacement of the sliding rod using the scale, enabling real-time and intuitive detection of the carbon brush sample's thermal expansion. This eliminates the need for additional complex sensing equipment, reducing detection costs and simplifying the detection process. Attached Figure Description
[0013] Figure 1 This is a schematic diagram of the overall structure of this utility model; Figure 2This is a schematic diagram of the movable seat, bearing plate, and frustum structure of this utility model; Figure 3 This is a schematic diagram of the clamping component and detection component of this utility model.
[0014] In the diagram: 1. Fixed frame; 11. Support leg; 2. Side plate; 21. Heating plate; 3. Movable seat; 31. Bearing plate; 32. Motor; 33. Guide rod; 34. Threaded rod; 35. Handle; 4. Frustum; 41. Placement slot; 5. Clamping assembly; 51. Angle iron; 52. Lead screw; 53. Rotary wheel; 54. Support plate; 6. Detection assembly; 61. L-plate; 62. Slide rod; 63. Contact plate; 64. Protrusion; 65. Spring; 66. Ruler. Detailed Implementation
[0015] like Figures 1-3 As shown, this utility model provides a technical solution: a sample fixing device for detecting the thermal expansion coefficient of carbon brushes, including a fixing frame 1. Four sets of symmetrically arranged support legs 11 are fixedly connected to the bottom surface of the fixing frame 1. The four sets of symmetrically arranged support legs 11 support the fixing frame 1, maintaining a certain distance between the device and the ground to prevent direct contact between the bottom of the device and the ground, thus avoiding wear. A side plate 2 is fixedly connected to the end of the fixing frame 1. A heating plate 21 is fixedly installed on the side wall of the side plate 2. The side plate 2 is the mounting carrier for the heating plate 21, used to fix the heating plate 21. After being energized, it can generate stable heat, providing the high-temperature environment required for the thermal expansion detection of the carbon brush sample. A movable seat 3 is slidably connected to the inner wall of the fixed frame 1. A bearing plate 31 is fixedly connected to the surface of the movable seat 3. A frustum 4 is rotatably connected to the surface of the bearing plate 31. A motor 32 is fixedly connected to the surface of the movable seat 3. The output shaft of the motor 32 passes through the surfaces of the movable seat 3 and the bearing plate 31 and is fixedly connected to the bottom surface of the frustum 4. Two sets of through holes are provided on the side wall of the movable seat 3. A guide rod 33 is slidably connected in one set of through holes and is fixedly connected to the inner wall of the fixed frame 1. A threaded rod 34 is threadedly connected in the other set of through holes. The threaded rod 34 passes through and is rotatably connected to the inner wall of the fixed frame 1. One end of the threaded rod 34 is rotatably connected to the inner wall of the fixed frame 1, and the other end of the threaded rod 34 is fixedly connected to a crank 35. By manually turning the crank 35, the threaded rod 34 is rotated, causing the movable seat 3, under the action of the guide rod 33, to move the bearing plate 31 and the frustum 4 smoothly toward the heating plate 21, so that the carbon brush is close to the heating plate 21 for heating. Furthermore, during the heating process, the motor 32 is started so that its output shaft drives the frustum 4 to rotate at a uniform speed, so that the carbon brush sample rotates synchronously with the frustum 4, thereby allowing all parts of the sample to receive heat from the heating plate 21 evenly, avoiding deviations in the detection data caused by uneven local heating.
[0016] The surface of the frustum 4 has a placement groove 41 for placing a carbon brush sample. A clamping assembly 5 is installed inside the placement groove 41. The clamping assembly 5 includes an angle iron 51, which fits against the inner wall of the placement groove 41. A lead screw 52 is rotatably connected to the outer wall of the angle iron 51. A rotating wheel 53 is fixedly connected to the end of the lead screw 52. A support plate 54 is threaded onto the outer wall of the lead screw 52 and fixedly connected to the surface of the placement groove 41. By rotating the rotating wheel 53, the lead screw 52 causes the angle iron 51 to fit against the side wall of the carbon brush sample, stably clamping the sample and preventing displacement or detachment during rotation or heating.
[0017] A detection component 6 is provided on the side of the support plate 54. The detection component 6 includes an L-plate 61, which is fixedly connected to the side wall of the support plate 54. The side wall of the L-plate 61 has a through hole, and a slide rod 62 is slidably connected in the through hole. One end of the slide rod 62 is fixedly connected to a contact plate 63, and the other end of the slide rod 62 is fixedly connected to a protrusion 64. The contact plate 63 and the support plate 54 are elastically connected by a spring 65. A scale 66 is provided on the surface of the slide rod 62. Through the elastic support of the spring 65, the contact plate 63 is always in contact with the surface of the carbon brush sample. When the carbon brush sample expands due to heat, it pushes the slide rod 62 in the opposite direction, causing the spring 65 to compress. The operator can directly read the displacement of the slide rod 62 through the scale 66, realizing real-time and intuitive detection of the thermal expansion of the carbon brush sample. There is no need to configure additional complex sensing detection equipment, which reduces the detection cost and simplifies the detection process.
[0018] In this invention, during use, the operator places the carbon brush sample to be tested in the placement groove 41 on the surface of the frustum 4, aligning the side wall of the carbon brush sample with the clamping surface of the angle iron 51. Then, the operator manually rotates the rotating wheel 53, which drives the lead screw 52 to rotate synchronously. Since the lead screw 52 is threadedly connected to the support plate 54 and the angle iron 51 is fitted and limited against the inner wall of the placement groove 41, the rotational motion of the lead screw 52 is converted into the linear movement of the angle iron 51 along the inner wall of the placement groove 41 until the clamping surface of the angle iron 51 is tightly fitted against the side wall of the carbon brush sample, thus completing the stable clamping of the carbon brush sample and effectively preventing the sample from shifting or falling off during subsequent testing. According to the temperature gradient requirements for carbon brush thermal expansion coefficient testing, the operator manually turns the crank handle 35, which drives the threaded rod 34 to rotate on the inner wall of the fixed frame 1. Since the moving seat 3 is slidably connected to the guide rod 33 through a set of through holes, the guide rod 33 restricts the movement trajectory of the moving seat 3 to a straight line. The rotational movement of the threaded rod 34 is converted into the linear movement of the moving seat 3 along the guide rod 33, which in turn drives the bearing plate 31, the frustum 4 and the clamped carbon brush sample to move synchronously until the carbon brush sample and the heating plate 21 reach the preset distance.
[0019] Next, the operator turns on the power to the heating plate 21. After the heating plate 21 is powered on, it generates stable heat, providing a high-temperature environment required for thermal expansion detection of the carbon brush sample. At the same time, the motor 32 is started. The output shaft of the motor 32 drives the frustum 4 to rotate in a uniform circumferential direction. The frustum 4 drives the carbon brush sample to rotate synchronously, so that all parts of the carbon brush sample can receive heat from the heating plate 21 evenly, completely solving the problem of test data deviation caused by uneven local heating of the sample under the traditional fixing method.
[0020] During the thermal expansion of the carbon brush sample, the spring 65 always provides elastic support to the contact plate 63, ensuring that the contact plate 63 is in close contact with the surface of the carbon brush sample. As the temperature of the carbon brush sample rises and thermal expansion occurs, the expansion force of the sample pushes the contact plate 63 to move in the opposite direction. The contact plate 63 drives the slide rod 62 to slide synchronously along the through hole of the L plate 61, and the spring 65 is compressed accordingly. The operator can read the displacement of the slide rod 62 in real time by observing the scale value corresponding to the protrusion 64 on the scale 66. This displacement is the amount of thermal expansion of the carbon brush sample at the corresponding temperature. The operator can record the thermal expansion data at different heating times and temperatures according to the testing requirements, without the need for additional complex sensing and detection equipment, simplifying the testing process and reducing testing costs.
[0021] After the thermal expansion coefficient of the carbon brush sample is tested, the operator first turns off the power to the heating plate 21 and the switch of the motor 32 to stop the heating and rotation. After the carbon brush sample cools down to room temperature, the operator rotates the wheel 53 in the opposite direction to move the angle iron 51 away from the carbon brush sample and release the clamp on the carbon brush sample. Then the operator takes the tested carbon brush sample out of the placement slot 41.
[0022] The present invention has been described in detail above. However, modifications or improvements can be made to it, which will be obvious to those skilled in the art. Therefore, any modifications or improvements that do not depart from the spirit of the present invention are within the protection scope of the present invention.
Claims
1. A sample fixing device for detecting the thermal expansion coefficient of a carbon brush, comprising a fixing frame (1), characterized in that: A side plate (2) is fixedly connected to the end of the fixed frame (1). A heating plate (21) is fixedly installed on the side wall of the side plate (2). A movable seat (3) is slidably connected to the inner wall of the fixed frame (1). A bearing plate (31) is fixedly connected to the surface of the movable seat (3). A frustum (4) is rotatably connected to the surface of the bearing plate (31). A placement groove (41) is opened on the surface of the frustum (4). A clamping assembly (5) is provided inside the placement groove (41). The clamping assembly (5) includes an angle iron (51). The angle iron (51) is in contact with the inner wall of the placement groove (41). A lead screw (52) is rotatably connected to the outer wall of the angle iron (51). A rotating wheel (53) is fixedly connected to the end of the lead screw (52). A support plate (54) is threadedly connected to the outer wall of the lead screw (52). The support plate (54) is fixedly connected to the surface of the placement groove (41).
2. The sample fixing device for detecting the thermal expansion coefficient of a carbon brush according to claim 1, characterized in that: The side of the support plate (54) is provided with a detection component (6), which includes an L plate (61). The L plate (61) is fixedly connected to the side wall of the support plate (54). The side wall of the L plate (61) has a through hole, and a slide rod (62) is slidably connected in the through hole. One end of the slide rod (62) is fixedly connected to a contact plate (63), and the other end of the slide rod (62) is fixedly connected to a protrusion (64). The contact plate (63) and the support plate (54) are elastically connected by a spring (65).
3. The sample fixing device for detecting the thermal expansion coefficient of a carbon brush according to claim 1, characterized in that: A motor (32) is fixedly connected to the surface of the movable seat (3). The output shaft of the motor (32) passes through the surface of the movable seat (3) and the bearing plate (31) and is fixedly connected to the bottom surface of the frustum (4). Two sets of through holes are provided on the side wall of the movable seat (3). A guide rod (33) is slidably connected in one set of the through holes. The guide rod (33) is fixedly connected to the inner wall of the fixed frame (1).
4. The sample fixing device for detecting the thermal expansion coefficient of a carbon brush according to claim 3, characterized in that: Another set of through holes is threaded with a threaded rod (34), which is rotatably connected to the inner wall of the fixed frame (1). One end of the threaded rod (34) is rotatably connected to the inner wall of the fixed frame (1), and the other end of the threaded rod (34) is fixedly connected to a crank (35).
5. The sample fixing device for detecting the thermal expansion coefficient of a carbon brush according to claim 2, characterized in that: A scale (66) is provided on the surface of the slide bar (62).
6. The sample fixing device for detecting the thermal expansion coefficient of a carbon brush according to claim 1, characterized in that: The bottom surface of the fixed frame (1) is fixedly connected with four sets of symmetrically arranged support legs (11).