Device for detecting form and location tolerance of inner hole of brake drum

Abstract

The utility model relates to the technical field of brake drum detection, and discloses a brake drum inner hole form and location tolerance detection device which comprises a detection table, a detection mechanism is arranged on the upper surface of the detection table, a positioning mechanism is arranged on the upper surface of the detection table and located on the outer side of the detection mechanism, and the positioning mechanism comprises a C-shaped plate. An adjusting rod is rotatably connected to the upper surface of the C-shaped plate in a penetrating mode, a gear is fixedly connected to the lower end of the adjusting rod, a ratchet wheel is fixedly connected to the position, located above the C-shaped plate, of the outer portion of the adjusting rod in a sleeving mode, a locking mechanism is arranged on the position, located on the rear side of the adjusting rod, of the upper surface of the C-shaped plate, and racks are slidably connected to the surfaces of the left side and the right side of the interior of the C-shaped plate. One end of the rack is fixedly connected with a positioning plate; the ratchet wheel and the pawl in the positioning mechanism are locked in a matched mode, it is guaranteed that clamping is stable and not loose, the positioning plate and the positioning blocks on the elastic plate are driven by transmission of the gear and the rack to clamp the brake drum in a self-adaptive mode, and the fixing requirements of brake drums of different specifications can be met.

Description

Technical Field

[0001] This utility model relates to the field of brake drum testing technology, specifically a device for detecting the form and position tolerances of the inner hole of a brake drum. Background Technology

[0002] The brake drum is the core component of a car's braking system. Its internal bore shape and position tolerances directly affect the uniformity of contact between the brake pads and the drum wall, which in turn determines braking performance, wear life, and driving safety.

[0003] In existing technologies, it is generally necessary to fix the brake drum using a tooling fixture and rotate a standard measuring piece along the inner wall of the brake drum, or to keep the standard measuring piece fixed and install a motor on the tooling fixture to drive the brake drum to rotate itself. Existing brake drum tolerance inspection methods have at least the following drawbacks:

[0004] 1. When measuring certain tolerances such as coaxiality, it is necessary to rotate the brake drum or standard measuring parts. If the brake drum is driven by a motor, it requires high energy consumption, which leads to an increase in equipment cost and energy cost.

[0005] Second, the brake drum or standard measuring parts are prone to displacement during rotation. Manufacturing errors of the brake drum and tooling fixtures will also affect the measured values ​​during the rotation of the brake drum, which can easily lead to measurement distortion and reduced tolerance measurement accuracy.

[0006] Chinese patent discloses a brake drum tolerance inspection device (authorization announcement number CN219829690U). This patented technology uses a positioning mandrel and a support surface to support and position the brake drum. By setting an angle between the support surface and the horizontal plane, the influence of manufacturing errors on tolerance inspection is eliminated. At the same time, this angle reduces the axial support force on the brake drum, making it easier for the brake drum to rotate around the positioning mandrel. The brake drum can be rotated manually, which helps to reduce the energy consumption required for rotating the brake drum and improves the convenience of tolerance inspection.

[0007] However, this technology still has obvious drawbacks: the arc and straight sections of the positioning mandrel are designed in a fixed manner, which cannot be adaptively adjusted according to the size of the positioning hole of the brake drum. This results in poor adaptability to brake drums of different specifications, and gaps or excessive tightness are easily generated during clamping, causing the positioning reference to shift or damage to the inner wall of the positioning hole. Utility Model Content

[0008] The purpose of this invention is to provide a device for detecting the form and position tolerances of the inner hole of a brake drum, so as to solve the problems mentioned in the background art.

[0009] To achieve the above objectives, this utility model provides the following technical solution:

[0010] A brake drum inner bore form and position tolerance inspection device includes an inspection table. An inspection mechanism is provided on the upper surface of the inspection table. A positioning mechanism is provided on the outer side of the inspection mechanism on the upper surface of the inspection table. The positioning mechanism includes a C-shaped plate. An adjusting rod is rotatably connected through the upper surface of the C-shaped plate. A gear is fixedly connected to the lower end of the adjusting rod, and a ratchet is fixedly sleeved on the outer side of the adjusting rod above the C-shaped plate. A locking mechanism is provided on the upper surface of the C-shaped plate behind the adjusting rod. A rack is slidably connected to both the left and right inner surfaces of the C-shaped plate. A positioning plate is fixedly connected to one end of the rack. An elastic plate is fixedly connected to one side of each of the two positioning plates facing each other. A positioning block is fixedly connected to the side of the elastic plate away from the positioning plate.

[0011] As a further embodiment of this utility model: the detection mechanism includes a rotating rod, the lower end of which is fixedly connected to a shell bearing, and a sliding sleeve is movably sleeved on the outside of the rotating rod. A support bolt is threaded through the front surface of the sliding sleeve, and a sliding tube is fixedly connected to the rear end of the sliding sleeve. A support bolt is threaded through the rear end of the upper surface of the sliding tube, and a sliding rod is movably connected inside the sliding tube. An indicator is fixedly connected to the rear end of the sliding rod.

[0012] As a further embodiment of this utility model: the locking mechanism includes a spring, a fixing block is fixedly connected to the rear end of the spring, and a pawl is fixedly connected to the front end of the spring, and a fixing rod is movably connected to the left end of the pawl.

[0013] As a further embodiment of this utility model: the lower end of the C-shaped plate is fixed to the upper surface of the testing table, and the C-shaped plate is located on the left side of the testing mechanism; the gear is meshed with the rack; and the two positioning plates are located on the front and rear sides of the testing mechanism, respectively.

[0014] As a further embodiment of this utility model: the shell bearing is fixed to the upper surface of the testing platform, the rear end of the first support bolt is attached to the rotating rod, and the lower end of the second support bolt is attached to the sliding rod.

[0015] As a further embodiment of this utility model: the pawl is attached to the ratchet, and the fixing block and the fixing rod are both fixed to the upper surface of the C-shaped plate.

[0016] Compared with the prior art, the beneficial effects of this utility model are:

[0017] This invention utilizes a ratchet and pawl locking mechanism in its positioning system to ensure secure clamping without loosening. Gear and rack transmission drives the positioning plate and the positioning block on the elastic plate to adaptively clamp the brake drum, accommodating the fixing requirements of brake drums of different sizes. During operation, only the adjusting rod needs to be rotated for quick positioning and release. Combined with the multi-directional adjustment function of the sliding sleeve and sliding rod in the detection mechanism, the alignment process of the indicator is simplified. The overall structure balances clamping reliability, ease of operation, and detection adaptability, significantly improving detection efficiency and accuracy. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of a brake drum inner bore form and position tolerance detection device.

[0019] Figure 2 This is a schematic diagram of the detection mechanism in the brake drum inner bore form and position tolerance detection device.

[0020] Figure 3 This is a schematic diagram of the positioning mechanism in the brake drum inner bore form and position tolerance detection device.

[0021] Figure 4 This is a schematic diagram of the locking mechanism in the brake drum inner bore form and position tolerance detection device.

[0022] In the diagram: 1. Testing table; 2. Testing mechanism; 3. Rotating rod; 4. Shell bearing; 5. Sliding sleeve; 6. Support bolt one; 7. Sliding tube; 8. Support bolt two; 9. Sliding rod; 10. Indicator; 11. Positioning mechanism; 12. C-shaped plate; 13. Adjusting rod; 14. Gear; 15. Ratchet; 16. Locking mechanism; 17. Spring; 18. Fixing block; 19. Pawl; 20. Fixing rod; 21. Rack; 22. Positioning plate; 23. Elastic plate; 24. Positioning block; 25. Brake drum. Detailed Implementation

[0023] Please see Figure 1 and Figure 2 In this embodiment of the present invention, the brake drum inner hole form and position tolerance detection device includes a detection platform 1, a detection mechanism 2 is provided on the upper surface of the detection platform 1, the detection mechanism 2 includes a rotating rod 3, a shell bearing 4 is fixedly connected to the lower end of the rotating rod 3, the shell bearing 4 is fixedly connected to the upper surface of the detection platform 1, a sliding sleeve 5 is movably sleeved on the outside of the rotating rod 3, a support bolt 6 is threadedly connected to the front surface of the sliding sleeve 5, the rear end of the support bolt 6 is attached to the rotating rod 3, a sliding tube 7 is fixedly connected to the rear end of the sliding tube 7, a support bolt 8 is threadedly connected to the rear end of the upper surface of the sliding tube 7, and a sliding rod 9 is movably connected inside the sliding tube 7, the lower end of the support bolt 8 is attached to the sliding rod 9, and an indicator 10 is fixedly connected to the rear end of the sliding rod 9.

[0024] The shell bearing 4 includes a housing, an outer bearing ring fixed in the housing, and an inner bearing ring rotating in the outer bearing ring; the rotating rod 3 is fixed in the inner bearing ring, so the rotating rod 3 and the shell bearing 4 are in a state of mutual rotation.

[0025] The brake drum 25 is placed on the upper surface of the test bench 1 and is located outside the test mechanism 2. During the test, the center line of the brake drum 25 and the rotating rod 3 are the same line.

[0026] Loosening support bolt 6 is used to adjust the height of indicator 10, and loosening support bolt 8 is used to adjust the exposed length of slide rod 9, so that indicator 10 fits into the inner hole of brake drum 25. Indicator 10 moves in a circle through rotating rod 3 to perform detection.

[0027] The indicator 10 is preferably a dial indicator. Its probe is connected to the body through a precision bearing and can slide freely along the axis. When the probe contacts the surface to be measured, it will contract inward after being pressed. The amount of contraction is proportional to the external force. A spring is installed inside the body to provide axial restoring force for the probe. The spring stiffness is calibrated to ensure that the probe can rebound stably after being pressed, while avoiding rigid contact that could damage the surface to be measured.

[0028] exist Figure 1 , Figure 3 and Figure 4 In the middle section: A positioning mechanism 11 is provided on the upper surface of the testing table 1 outside the testing mechanism 2. The positioning mechanism 11 includes a C-shaped plate 12. The lower end of the C-shaped plate 12 is fixed to the upper surface of the testing table 1, and the C-shaped plate 12 is located on the left side of the testing mechanism 2. An adjusting rod 13 is rotatably connected through the upper surface of the C-shaped plate 12. A gear 14 is fixed to the lower end of the adjusting rod 13, and a ratchet 15 is fixedly sleeved on the outside of the adjusting rod 13 above the C-shaped plate 12. A locking mechanism 16 is provided on the upper surface of the C-shaped plate 12 behind the adjusting rod 13. The locking mechanism 16 includes a spring 17, and a fixing block is fixed to the rear end of the spring 17. 18, and a pawl 19 is fixedly connected to the front end of the spring 17. The pawl 19 is attached to the ratchet 15. A fixing rod 20 is movably connected to the left end of the pawl 19. The fixing block 18 and the fixing rod 20 are both fixedly connected to the upper surface of the C-shaped plate 12. The left and right sides of the interior of the C-shaped plate 12 are slidably connected to the rack 21. The gear 14 is meshed with the rack 21. A positioning plate 22 is fixedly connected to one end of the rack 21. The two positioning plates 22 are located on the front and rear sides of the detection mechanism 2, respectively. An elastic plate 23 is fixedly connected to the opposite side surface of the two positioning plates 22. A positioning block 24 is fixedly connected to the side surface of the elastic plate 23 away from the positioning plate 22.

[0029] Pad 19 engages with ratchet 15, allowing ratchet 15 and adjusting rod 13 to rotate normally, but not counterclockwise. Pulling pad 19 away from ratchet 15 allows it to rotate counterclockwise.

[0030] Rotating the adjusting rod 13 clockwise causes the two racks 21 to move relative to each other under the action of the gear 14, thereby bringing the two positioning plates 22 closer together. The positioning blocks 24 then clamp and position the brake drum 25. Under the action of the pawl 19 and the ratchet 15, the two positioning blocks 24 will not move in opposite directions, thus preventing the clamping from becoming loose.

[0031] The material of the elastic plate 23 is preferably rubber;

[0032] The two positioning blocks 24 are respectively positioned on the front and rear sides of the brake drum 25; the opposite side surfaces of the two positioning blocks 24 are both angular surfaces, which are suitable for fixing brake drums 25 of different specifications.

[0033] The working principle of this utility model is as follows: During testing, the brake drum 25 is placed on the upper surface of the testing table 1 and located outside the testing mechanism 2. The adjusting rod 13 is rotated clockwise, which drives the racks 21 on both sides to move relative to each other through the gear 14, so that the positioning blocks 24 on the two positioning plates 22 and the elastic plate 23 clamp the brake drum 25. The pawl 19 cooperates with the ratchet 15 to prevent loosening. The support bolt 16 is loosened to adjust the height of the sliding sleeve 5, and the support bolt 28 is loosened to adjust the extension length of the sliding rod 9, so that the indicator 10 contacts the inner wall of the brake drum 25. The sliding rod 9 is rotated to drive the indicator 10 to make a circular motion along the inner hole to detect the form and position tolerance. After completion, the pawl 19 is pulled back to disengage from the ratchet 15 and the adjusting rod 13 is rotated counterclockwise to release the positioning block 24 from the brake drum 25, so that the workpiece can be removed.

[0034] The above description is only a preferred embodiment of the present utility model, but the protection scope of the present utility model is not limited thereto. Any equivalent substitutions or changes made by those skilled in the art within the technical scope disclosed in the present utility model, based on the technical solution and inventive concept of the present utility model, should be included within the protection scope of the present utility model.

[0035] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

Claims

1. A brake drum inner bore form and position tolerance detection device, comprising a detection platform (1), wherein a detection mechanism (2) is provided on the upper surface of the detection platform (1), characterized in that, The upper surface of the testing platform (1) is provided with a positioning mechanism (11) located outside the testing mechanism (2). The positioning mechanism (11) includes a C-shaped plate (12). An adjusting rod (13) is rotatably connected through the upper surface of the C-shaped plate (12). A gear (14) is fixedly connected to the lower end of the adjusting rod (13). A ratchet (15) is fixedly sleeved on the outside of the adjusting rod (13) above the C-shaped plate (12). A locking mechanism (16) is provided on the upper surface of the C-shaped plate (12) behind the adjusting rod (13). A rack (21) is slidably connected to the left and right surfaces inside the C-shaped plate (12). A positioning plate (22) is fixedly connected to one end of the rack (21). An elastic plate (23) is fixedly connected to the opposite side surface of the two positioning plates (22). A positioning block (24) is fixedly connected to the side surface of the elastic plate (23) away from the positioning plate (22).

2. The brake drum inner bore form and position tolerance detection device according to claim 1, characterized in that, The detection mechanism (2) includes a rotating rod (3), the lower end of which is fixedly connected to a shell bearing (4), and a sliding sleeve (5) is movably sleeved on the outside of the rotating rod (3). A support bolt (6) is threaded through the front surface of the sliding sleeve (5), and a sliding tube (7) is fixedly connected to the rear end of the sliding sleeve (5). A support bolt (8) is threaded through the rear end of the upper surface of the sliding tube (7), and a sliding rod (9) is movably connected inside the sliding tube (7). A value indicator (10) is fixedly connected to the rear end of the sliding rod (9).

3. The brake drum inner bore form and position tolerance detection device according to claim 1, characterized in that, The locking mechanism (16) includes a spring (17), a fixing block (18) is fixedly connected to the rear end of the spring (17), and a pawl (19) is fixedly connected to the front end of the spring (17). A fixing rod (20) is movably connected to the left end of the pawl (19).

4. The brake drum inner bore form and position tolerance detection device according to claim 1, characterized in that, The lower end of the C-shaped plate (12) is fixed to the upper surface of the testing table (1), and the C-shaped plate (12) is located on the left side of the testing mechanism (2). The gear (14) is meshed with the rack (21), and the two positioning plates (22) are located on the front and rear sides of the testing mechanism (2) respectively.

5. The brake drum inner bore form and position tolerance detection device according to claim 2, characterized in that, The shell bearing (4) is fixed to the upper surface of the test bench (1), the rear end of the first support bolt (6) is attached to the rotating rod (3), and the lower end of the second support bolt (8) is attached to the sliding rod (9).

6. The brake drum inner bore form and position tolerance detection device according to claim 3, characterized in that, The pawl (19) is attached to the ratchet (15), and the fixing block (18) and the fixing rod (20) are both fixed to the upper surface of the C-shaped plate (12).

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