A pneumatic ratchet test fixture with self-locking vibration resistance

Abstract

This invention relates to the field of clamping technology, and discloses a pneumatic ratchet wrench test clamp with a self-locking anti-vibration design. The clamp includes a base, a ratchet wrench, and a brake pad, and also includes a pneumatically controlled clamp mounted on the base. The pneumatically controlled clamp is used to limit the ratchet wrench's position. The output end of the ratchet wrench cooperates with the brake pad. The pneumatically controlled clamp includes: two sets of half-shells, symmetrically fixed, for clamping the ratchet wrench; each half-shell has an air-drawing chamber inside; several sets of clamping components installed within the air-drawing chambers, which are compressed against the ratchet wrench by airflow; and an air exchange shell installed outside the two sets of half-shells for closing and opening the ends of the two sets of half-shells. This invention, through the design of the pneumatically controlled clamp, achieves continuous clamping force compensation driven by airflow. The clamping components are always driven by airflow during testing to maintain a tightened state, which can compensate for the micron-level gaps caused by vibration in real time, solving the clamping failure problem caused by stress relaxation in traditional rigid clamps.

Description

Technical Field

[0001] This invention relates to the field of fixture technology, specifically to a pneumatic ratchet test fixture with a self-locking anti-vibration design. Background Technology

[0002] Pneumatic ratchet wrenches, as efficient power tools, are widely used in automotive manufacturing, machinery repair, aerospace, and other fields. Their core function is to quickly tighten or loosen bolts by using compressed air to drive a ratchet mechanism. With increasing industrial automation, the market demands increasingly stringent performance requirements for pneumatic tools. For example, the stability of torque output, the accuracy of speed control, and durability directly impact production efficiency and operational safety. Therefore, standardized and systematic testing of pneumatic ratchet wrenches has become a crucial step in ensuring product quality and user safety.

[0003] Currently, there are devices available for testing and inspecting pneumatic ratchet wrenches. When testing or inspecting pneumatic ratchet wrenches, the wrenches need to withstand high-frequency vibration, impact loads, and large torque reaction forces. Traditional test fixtures are prone to positioning deviation or clamping failure due to vibration, which directly affects the accuracy of test data. In addition, long-term vibration causes fatigue damage to the mechanical structure, accelerates sensor drift or failure, and shortens the service life of the test equipment.

[0004] Currently, the rigid clamping method, even when clamped tightly, still has a certain degree of looseness in different directions. This is because the microscopic unevenness of the contact surface between the clamp and the wrench leads to uneven distribution of clamping stress. Under vibration excitation, local contact points undergo plastic deformation, producing micron-level displacement, which gradually reduces clamping stability. In addition, traditional rigid clamping only suppresses unidirectional displacement through vertical clamping force, but vibration energy can cause the wrench to slide laterally, or even cause loosening in multiple degrees of freedom. Summary of the Invention

[0005] The purpose of this invention is to provide a self-locking anti-vibration fixture for a pneumatic ratchet test clamp, so as to solve the problems mentioned in the background art.

[0006] To solve the above-mentioned technical problems, the present invention provides the following technical solution: a pneumatic ratchet wrench test fixture with self-locking vibration resistance, comprising a base, a ratchet wrench, and a brake pad, and further comprising a pneumatically controlled clamp mounted on the base, wherein the pneumatically controlled clamp is used to limit the ratchet wrench, the output end of the ratchet wrench cooperates with the brake pad, and the pneumatically controlled clamp includes:

[0007] Two sets of half-shells are fixed symmetrically to hold the ratchet wrench, and an air-drawing cavity is formed inside each half-shell.

[0008] Several sets of clamping components are installed inside the air intake chamber, and are squeezed by the ratchet wrench by the action of wind force;

[0009] The gas exchange shell is installed on the outside of the two sets of half-shells and is used to close and open the ends of the two sets of half-shells to allow the gas to move in different directions.

[0010] Furthermore, the brake pad has an integral polygonal end on its outer end, which engages with the output end of the ratchet wrench, and the brake pad can adjust the resistance.

[0011] Furthermore, the semi-shell includes a shell one and a shell two. The axes of the shell one and the shell two coincide, and the shell one is located outside the shell two. A buckle plate is fixed on the inner side of the shell one, and the outer side of the shell two has a buckle groove that cooperates with the buckle plate. The shell one and the shell two form an air-guiding cavity through the gap of the buckle plate.

[0012] One of the shells in the set of half-shells is fixed to the base.

[0013] Furthermore, both shell one and shell two of the two sets of semi-shells have extension plates extending from their sides, and multiple sets of the extension plates are stacked and fixed by bolts.

[0014] Furthermore, the outer side of the housing has multiple sets of through threaded holes, and the clamping assembly includes a windproof frame, a threaded shaft, and multiple sets of drive plates.

[0015] The threaded shaft is threadedly engaged with the threaded hole, the inner end of the threaded shaft abuts against the ratchet wrench, the wind-blocking frame is fixed on the outer side of the housing, the wind-blocking frame coincides with the axis of the threaded shaft, and the wind-blocking frame partially covers the threaded shaft, and several sets of the drive plates are fixed on the outer wall of the threaded shaft near the outer end.

[0016] Furthermore, the inner end of the threaded shaft is semi-circular.

[0017] Furthermore, the outer side of the overlapping extension piece is provided with a slot, and the ventilation shell includes two cover shells and a connecting strip for connecting the two cover shells. The outer side of each of the two cover shells has multiple air inlet holes that cooperate with different air ducts.

[0018] The two cover shells are located at both ends of the two sets of half shells, respectively covering both ends of the two sets of half shells. There are at least two connecting strips, which are respectively attached to the outside of the two sets of half shells. The length of the connecting strips is greater than the length of the two sets of half shells. The cover shells on both sides can be engaged with the slots on both sides. When one cover shell engages with the slot on one side, the cover shell on the other side will automatically disengage from the slot on the other side.

[0019] Furthermore, the outer side of the cover shell has a locking block, and the locking groove is L-shaped. When the cover shell is engaged with the locking groove, the locking block can rotate and fit into the locking groove to form a self-locking mechanism.

[0020] Compared with the prior art, the beneficial effects achieved by the present invention are:

[0021] 1. Through the design of pneumatically controlled clamps, the continuous clamping force compensation effect driven by wind is realized. The clamping components are always driven by airflow to maintain a tight state during the test, which can offset the micron-level gap caused by vibration in real time, and solve the clamping failure problem caused by stress relaxation of traditional rigid clamps.

[0022] 2. Driven by wind power, the pressure between the threaded shaft and the ratchet wrench at each position is similar. At the same time, the effect of wind power is limited, so the pressure between the threaded shaft and the ratchet wrench is limited, avoiding excessive pressure marks on the surface of the ratchet wrench.

[0023] 3. By limiting the ratchet wrench at multiple points in the circumferential direction, a geometrically adaptive clamping is formed. Even if the wrench has shape tolerances or vibration deformation, a uniform stress distribution can still be achieved through independent adjustment of each contact point, effectively reducing the risk of plastic deformation of the contact surface and effectively suppressing the ratchet wrench's multi-degree-of-freedom loosening. Attached Figure Description

[0024] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used in conjunction with embodiments of the invention to explain the invention and do not constitute a limitation thereof. In the drawings:

[0025] Figure 1 This is a schematic diagram of the overall structure of the present invention;

[0026] Figure 2 This is a schematic diagram of the separation structure of the brake pad and ratchet wrench of the present invention;

[0027] Figure 3 This is a schematic diagram of the separation structure of the air exchange shell and the pneumatic control fixture of the present invention;

[0028] Figure 4 This is a partially exploded structural diagram of the pneumatically controlled clamp of the present invention;

[0029] Figure 5 This is the present invention. Figure 4 A schematic diagram of the partially enlarged structure of the middle part;

[0030] Figure 6 This is a schematic diagram of the planar structure of the pneumatically controlled clamp of the present invention;

[0031] Figure 7 This is a schematic diagram of the cover shell structure of the present invention;

[0032] Figure 8 This is the present invention. Figure 7 A magnified schematic diagram of part B.

[0033] In the diagram: 1. Base; 2. Pneumatic clamp; 21. Housing 1; 211. Buckle plate; 22. Housing 2; 221. Buckle groove; 222. Threaded hole; 23. Clamping assembly; 231. Air baffle frame; 232. Threaded shaft; 233. Drive plate; 24. Air exchange housing; 241. Cover housing; 242. Connecting strip; 243. Air inlet; 244. Locking block; 245. Locking groove; 25. Extension piece; 26. Air intake chamber; 3. Ratchet wrench; 4. Brake pad; 41. Polygonal end. Detailed Implementation

[0034] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0035] Please see Figures 1-8 This invention provides a technical solution: Before testing, the ratchet wrench 3 is fixed by a clamp. However, this clamping is typically a one-time, direct fixation and does not provide additional clamping during subsequent testing, leading to situations where the ratchet wrench 3 is not fully secured. Even when fully secured, microscopic unevenness may exist on the contact surface between the clamp and the ratchet wrench 3. While manually shaking or wiggling the ratchet wrench 3 after initial fixation provides complete stability, micron-level displacement can occur during operation, causing vibration. Based on this, an improvement is proposed: a self-locking anti-vibration fixture for a pneumatic ratchet wrench testing fixture, such as... Figure 1-Figure 4 As shown, the device includes a base 1, a ratchet wrench 3, and a brake pad 4. It also includes a pneumatic clamp 2 mounted on the base 1. The pneumatic clamp 2 is used to limit the ratchet wrench 3. The output end of the ratchet wrench 3 engages with the brake pad 4. The pneumatic clamp 2 includes:

[0036] Two sets of half-shells are fixed symmetrically to hold the ratchet wrench 3, and an air-guiding cavity 26 is formed inside the half-shell;

[0037] Several sets of clamping components 23 are installed in the air chamber 26 and are squeezed by the ratchet wrench 3 by the action of wind force;

[0038] The air exchange shell 24 is installed on the outside of the two sets of half shells and is used to close and open the ends of the two sets of half shells to realize the movement of gas in different directions.

[0039] Specifically, a brake pad 4 for testing the ratchet wrench 3 is simply installed on the base 1. The ratchet wrench 3 is installed on the base 1 via a pneumatic clamp 2. The pneumatic clamp 2 is configured as two sets of half-shells, which can cooperate with each other or separate from each other. The half-shells have multiple air-guiding chambers 26 inside, and the air-guiding chambers 26 have clamping components 23. The clamping components 23 are driven by the gas moving in the air-guiding chambers 26. Even when the ratchet wrench 3 is working, the gas in the air-guiding chambers 26 continues to move, maintaining the clamping force of the clamping components 23 on the ratchet wrench 3. Even if the ratchet wrench 3 experiences local vibration, it will be tightened immediately.

[0040] like Figure 2 The brake pad 4 shown is separate from the ratchet wrench 3. The outer end of the brake pad 4 has an integral polygonal end 41, which is engaged with the output end of the ratchet wrench 3. The brake pad 4 can adjust the resistance. The brake pad 4 is driven to rotate by the pneumatic action of the ratchet wrench 3 to achieve detection. This detection method is an existing technology.

[0041] like Figure 4 The diagram shows two sets of half-shells, with the upper half-shell consisting of a first shell 21 and a second shell 22. The axes of the first shell 21 and the second shell 22 coincide, and the first shell 21 is located outside the second shell 22. A buckle plate 211 is fixed to the inner side of the first shell 21, and the outer side of the second shell 22 has a buckle groove 221 that mates with the buckle plate 211. The first shell 21 and the second shell 22 form an air-drawing cavity 26 through the gap of the buckle plate 211.

[0042] The shell 21 of a set of half-shells is fixed to the base 1.

[0043] Specifically, the half-shell includes a first shell 21 and a second shell 22. Both the first shell 21 and the second shell 22 have extension tabs 25 on their edges. The two sets of extension tabs 25 overlap and are fixed together by the two sets of extension tabs 25. The first shell 21 and the second shell 22 of the two half-shells are arranged symmetrically from top to bottom and are fixed by bolts on the extension tabs 25. The inner side of the first shell 21 has a buckle plate 211 that engages with the buckle groove 221 of the second shell 22, thereby forming multiple air-guiding chambers 26. The clamping assembly 23 is located within the air-guiding chambers 26.

[0044] like Figure 4 As shown, both shell 1 21 and shell 2 22 in the two sets of half shells have extension plates 25 extending from their sides. Multiple sets of extension plates 25 are stacked and fixed by bolts. It should be noted that the function of the extension plates 25 is to fix shell 1 21 and shell 2 22 in the two sets of half shells to each other to form a whole, so as to avoid vibration caused by the ratchet wrench 3 after clamping.

[0045] like Figure 5As shown, the outer side of the housing 22 has multiple sets of through threaded holes 222, and the clamping assembly 23 includes a windproof frame 231, a threaded shaft 232 and multiple sets of drive plates 233.

[0046] The threaded shaft 232 is threadedly engaged with the threaded hole 222. The inner end of the threaded shaft 232 abuts against the ratchet wrench 3. The wind-blocking frame 231 is fixed on the outer side of the housing 22. The wind-blocking frame 231 coincides with the axis of the threaded shaft 232, and the wind-blocking frame 231 partially covers the threaded shaft 232. Several sets of drive plates 233 are fixed on the outer wall of the threaded shaft 232 near the outer end.

[0047] Specifically, the threaded shaft 232 is threadedly connected to the housing 22 through the threaded hole 222 on the housing 22. The multi-dry drive plate 233 is fixed on the outside of the threaded shaft 232, and the wind baffle 231 blocks half of the drive plate 233. The shape of the drive plate 233 can be set to a straight or arc shape according to the actual situation. Changing the shape of the drive plate 233 mainly affects the thrust generated by the gas.

[0048] like Figure 6 As shown, the inner end of the threaded shaft 232 is semi-circular. This semi-circular portion abuts against the ratchet wrench 3. Even with slight deviations in the shape of the ratchet wrench 3, contact can be maintained through geometric adaptation. If the inner end of the threaded shaft 232 were flat, it would have a certain edge. When this edge is pressed against the ratchet wrench 3, it could easily leave marks on the ratchet wrench 3. It should also be noted that multiple sets of threaded shafts 232 are distributed circumferentially, such as... Figure 6 As shown, the pressure on ratchet wrench 3 is more comprehensive.

[0049] like Figure 7 and Figure 8 The diagram shows the structure of the ventilation shell 24. The outer side of the stacked extension piece 25 is provided with a slot 245. The ventilation shell 24 includes two cover shells 241 and a connecting strip 242 for connecting the two cover shells 241. The outer side of each of the two cover shells 241 has multiple air inlets 243 that cooperate with different air ducts 26.

[0050] Two cover shells 241 are located at both ends of the two sets of half shells, respectively covering both ends of the two sets of half shells. There are at least two connecting strips 242, which are respectively attached to the outside of the two sets of half shells. The length of the connecting strips 242 is greater than the length of the two sets of half shells. The cover shells 241 on both sides can cooperate with the slots 245 on both sides. One side of the cover shell 241 cooperates with one side of the slot 245, and the other side of the cover shell 241 will automatically uncooperate with the other side of the slot 245.

[0051] Specifically, when one side of the cover shell 241 is engaged with the two sets of half shells, the length of the two sets of cover shells 241 is fixed because they are connected by a connecting strip 242. Then, the other side of the cover shell 241 will not be engaged with the two sets of half shells. The two sets of half shells can take in air on one side with the cover shell 241 and take out air on the other side, so that the threaded shaft 232 can rotate. Conversely, when the threaded shaft 232 needs to be reversed, the other side of the cover shell 241 is engaged with the two sets of half shells to allow the gas to enter in the opposite direction, so that the threaded shaft 232 can be reversed and the threaded shaft 232 can be loosened.

[0052] like Figure 8 As shown, the outer side of the cover shell 241 has a locking block 244 and a locking groove 245 is L-shaped. When the cover shell 241 and the locking groove 245 are engaged, the locking block 244 can rotate and fit into the locking groove 245 to form a self-locking mechanism.

[0053] Specifically, in order to make the cover shell 241 more secure, the locking block 244 can rotate to cooperate with the L-shaped locking slot 245 to achieve further tightening, which is convenient for both tightening and disassembly.

[0054] The working principle of this invention is as follows: First, the ratchet wrench 3 is extended into the pneumatic clamp 2. Then, the ratchet wrench 3 engages with the polygonal end 41 of the brake pad 4. Next, one end of the two sets of half-shells is covered by a cover shell 241 on one side, and airflow is delivered through the air inlet 243. The airflow quickly passes through the air intake chamber 26, driving the clamping assembly 23 to bear force. Due to the obstruction of the air baffle 231, the drive plate 233 rotates, driving the threaded shaft 232 to move inward, thus squeezing the ratchet wrench 3 and limiting its position. It should be noted that the gas flow rate delivered by each air inlet 243 is the same, ensuring that the squeezing force on the ratchet wrench 3 is the same after each threaded shaft 232 rotates, guaranteeing that the ratchet wrench 3 is clamped. It should also be noted that since the threaded shaft 232 is driven to rotate by wind power, the squeezing effect between the threaded shaft 232 and the ratchet wrench 3 is limited, which can prevent excessive pressure marks from being produced on the surface of the ratchet wrench 3. The threaded shaft 232 has a self-locking function under the action of threaded engagement, which can prevent the ratchet wrench 3 from loosening.

[0055] It should also be noted that the air inlet 243 delivers airflow continuously. During the inspection of the ratchet wrench 3, the threaded shaft 232 maintains a tightening force. Therefore, if the ratchet wrench 3 is not properly fixed or if local vibration or displacement occurs for other reasons, a slight gap will be generated between it and some threaded shafts 232. The threaded shafts 232 can then move further to fill the slight gap and prevent further vibration.

[0056] It should be noted that, in this document, relational terms such as first and second, etc., are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "comprises," "comprising," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that includes a list of elements includes not only those elements but also other elements not explicitly listed, or elements inherent to such process, method, article, or apparatus.

[0057] Finally, it should be noted that the above descriptions are merely preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A pneumatic ratchet test fixture with self-locking vibration resistance, comprising a base (1), a ratchet wrench (3), and a brake pad (4), characterized in that, It also includes a pneumatic clamp (2) mounted on the base (1), the pneumatic clamp (2) being used to limit the ratchet wrench (3), the output end of the ratchet wrench (3) cooperating with the brake pad (4), the pneumatic clamp (2) comprising: Two sets of half-shells are fixed symmetrically to hold the ratchet wrench (3), and an air-drawing cavity (26) is formed inside the half-shell. Several sets of clamping components (23) are installed in the air intake chamber (26) and are squeezed by the ratchet wrench (3) by the action of wind force; The gas exchange shell (24) is installed on the outside of the two sets of half shells to close and open the ends of the two sets of half shells, so as to realize the movement of gas in different directions. The half-shell includes a first shell (21) and a second shell (22). The axes of the first shell (21) and the second shell (22) coincide, and the first shell (21) is located outside the second shell (22). A buckle plate (211) is fixed inside the first shell (21), and the outer side of the second shell (22) has a buckle groove (221) that cooperates with the buckle plate (211). The first shell (21) and the second shell (22) form an air-drawing cavity (26) through the gap of the buckle plate (211). One of the shells (21) in the set of half-shells is fixed to the base (1); The outer side of the housing (22) has multiple sets of through threaded holes (222), and the clamping assembly (23) includes a windproof frame (231), a threaded shaft (232) and multiple sets of drive plates (233). The threaded shaft (232) is threadedly engaged with the threaded hole (222), the inner end of the threaded shaft (232) abuts against the ratchet wrench (3), the wind-blocking frame (231) is fixed on the outside of the housing (22), the wind-blocking frame (231) coincides with the axis of the threaded shaft (232), and the wind-blocking frame (231) partially covers the threaded shaft (232), and several sets of the driving plates (233) are fixed on the outer wall of the threaded shaft (232) near the outer end; The inner end of the threaded shaft (232) is semi-circular.

2. The pneumatic ratchet test fixture with self-locking vibration resistance according to claim 1, characterized in that: The brake pad (4) has an integral polygonal end (41) on its outer end, which is engaged with the output end of the ratchet wrench (3). The brake pad (4) can adjust the resistance.

3. The pneumatic ratchet test fixture with self-locking vibration resistance according to claim 1, characterized in that: Both shells of the two sets of half-shells, shell one (21) and shell two (22), have extension pieces (25) extending from their sides. Multiple sets of extension pieces (25) are stacked and fixed by bolts.

4. The pneumatic ratchet test fixture with self-locking vibration resistance according to claim 3, characterized in that: The outer side of the overlapping extension piece (25) is provided with a slot (245). The ventilation shell (24) includes two cover shells (241) and a connecting strip (242) for connecting the two cover shells (241). The outer side of the two cover shells (241) has multiple air inlets (243) that cooperate with different air ducts (26). The two cover shells (241) are located at both ends of the two sets of half shells respectively, covering both ends of the two sets of half shells. There are at least two connecting strips (242), which are respectively attached to the outside of the two sets of half shells. The length of the connecting strips (242) is greater than the length of the two sets of half shells. The cover shells (241) on both sides can cooperate with the slots (245) on both sides. One side of the cover shell (241) cooperates with one side of the slot (245), and the other side of the cover shell (241) will automatically cancel its cooperation with the other side of the slot (245).

5. The pneumatic ratchet test fixture with self-locking vibration resistance according to claim 4, characterized in that: The outer side of the cover shell (241) has a locking block (244), and the slot (245) is L-shaped. When the cover shell (241) and the slot (245) are engaged, the locking block (244) can rotate and fit into the slot (245) to form a self-locking mechanism.

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