Quick-release steel strand clamp

Abstract

The utility model belongs to the field of steel strand clamp, concretely relates to quick release type steel strand clamp, including two test machine clamping bodies that are oppositely arranged, the inside of test machine clamping body is equipped with cavity, be provided with clamp in the cavity, test machine clamping body side is provided with " U " type slot for the installation of clamp across, the clamp includes lock piece cover and lock piece, the lock piece cover is installed in the lock piece cover, the section of lock piece is trapezoidal, lock piece is provided with the lock piece inner hole for the crossing of steel cable, the position of test machine clamping body close mouth portion still is provided with push top subassembly, push top subassembly is used for quick release clamp after steel strand test is finished. The utility model discloses through setting up push top subassembly, has guaranteed the premise of clamping stable, has realized quick, labor -saving, safe's dismounting, has effectively protected the equipment, has improved detection efficiency greatly.

Description

Technical Field

[0001] This utility model belongs to the field of steel strand clamps, specifically relating to quick-release steel strand clamps. Background Technology

[0002] As a key load-bearing component in prestressed concrete structures and geotechnical anchorage projects, the mechanical performance testing of steel strands is crucial. Currently, dovetail clamps are commonly used in tensile tests of steel strands, utilizing their unique inclined plane self-locking principle to clamp and fix the steel cable until the specimen fractures under tension. While this structure provides reliable clamping force, it reveals significant drawbacks after testing: under ultimate load, the locking plate and dovetail groove generate extremely high normal pressure and friction, causing the clamp to "lock up" with the testing machine's fixture, making disassembly exceptionally difficult. Operators typically need to use hammers, pry bars, or other external forces, which is not only time-consuming and labor-intensive, reducing testing efficiency, but may also damage the clamp and testing machine itself. This contradiction is particularly prominent in laboratory environments requiring frequent and rapid batch testing. Therefore, there is an urgent need in this field for an innovative clamping solution that must fundamentally solve the problem of rapid disassembly after testing, while ensuring clamping stability during tensile testing is no less than that of traditional dovetail clamps, thereby achieving a balance between safety, efficiency, and convenience. Summary of the Invention

[0003] To address the technical problems existing in the prior art and achieve the above objectives, this utility model provides a quick-release steel strand clamp, comprising two test machine clamp bodies arranged opposite each other. Each test machine clamp body has an internal cavity containing a clamp. The side of each test machine clamp body has a U-shaped groove for the clamp to pass through. Each clamp includes a locking sleeve and a locking plate. The locking plate is fitted into the locking sleeve, and the locking plate has a trapezoidal cross-section. The locking plate has an inner hole for the steel cable to pass through. A push-pull assembly is also provided near the opening of each test machine clamp body for quick disassembly of the clamp after the steel strand test is completed.

[0004] Furthermore, the push assembly is a screw-type first push sleeve. The testing machine fixture has a first push sleeve mounting hole near the opening. The first push sleeve has a first push boss at the end near the fixture. The locking sleeve has an annular groove. The outer diameter of the first push boss matches the inner diameter of the annular groove on the locking sleeve. The first push sleeve also has an inner hole in the middle for the steel cable to pass through.

[0005] Furthermore, the push assembly includes a second push sleeve, a hydraulic cylinder, a hydraulic cylinder telescopic rod, and a pull rod. The hydraulic cylinder telescopic rod is connected to the hydraulic cylinder and installed at the tail of the testing machine fixture. The testing machine fixture has an axial through hole, and a pull rod slides through the axial through hole. One end of the pull rod is connected to the hydraulic cylinder telescopic rod, and the other end is connected to the second push sleeve. The second push sleeve has a second push boss at the end near the fixture. The second push boss abuts against the locking plate. The second push sleeve also has an inner hole in the middle for the steel cable to pass through.

[0006] Furthermore, sensors are connected to both the upper and lower sides of the steel cable.

[0007] Furthermore, the bottom of the cavity of the testing machine clamp is provided with an oblique groove for accommodating the locking piece.

[0008] Furthermore, the locking plates consist of 3 to 6 pieces.

[0009] This utility model has the following features and beneficial effects: The core of this utility model lies in the addition of a specialized "push-out component" near the opening of the traditional clamp. After the test is completed, this component can actively apply a reverse push-out force, directly acting on the locking plate, effectively overcoming the static friction and self-locking force between it and the inner cavity of the testing machine clamp, thereby easily pushing the clamp out of the "U" groove. This fundamentally solves the problem of traditional dovetail groove clamps being "locked up" and difficult to disassemble, greatly improving testing efficiency. This utility model specifically discloses two implementation schemes for the push-out component. One is a rotary mechanical push-out, which achieves mechanical push-out by rotating the first push-out sleeve with the push-out boss. It has a simple structure, convenient operation, and low cost. The other is a hydraulically driven push-out, which drives the second push-out sleeve through a cylinder, telescopic rod, and pull rod. The push force is stable and powerful, especially suitable for large-scale or extremely high-clamping-force testing scenarios, realizing automated or semi-automated disassembly, further improving the convenience and safety of operation. The improvement of this utility model focuses on the disassembly process and does not change the core force-bearing structure of the clamp during the stretching process. The trapezoidal cross-section design of the locking plates and locking plate sleeves, combined with the oblique groove at the bottom of the testing machine's fixture, provides a stable and reliable self-locking clamping force, ensuring that the steel strand will not slip during tensile testing and that the test data is accurate and reliable. The push-out assembly only intervenes after the test, perfectly balancing the two core requirements of "tight clamping" and "quick disassembly." Disassembling the fixture through standardized push-out operations completely avoids the use of hammers, pry bars, or other rough handling, eliminating potential safety risks to operators and preventing damage to the expensive testing machine fixture and fixture itself, thus extending the equipment's service life. The push-out sleeves all have inner holes in the middle for the steel cable to pass through, ensuring that it will not interfere with the steel strand or any connected sensors during operation. Furthermore, the 3-6 plate locking plate design provides more flexible clamping force options, better adapting to steel strands of different specifications and surface conditions. Attached Figure Description

[0010] Figure 1 This is a schematic diagram of the fixture body and fixture installation structure of the utility model testing machine; Figure 2 for Figure 1 Enlarged view of section A; Figure 3 This is a schematic diagram of the three-dimensional mechanism of the testing machine clamp of this utility model; Figure 4 This is an exploded view of the fixture body and clamps of the testing machine of this utility model; Figure 5 This is a schematic diagram of the manual quick-release steel strand clamp structure of this utility model; Figure 6 for Figure 5 Sectional view at point BB; Figure 7 This is a schematic diagram of the automatic quick-release steel strand clamp structure of this utility model; Figure 8 for Figure 7 Sectional view at CC; Figure 9 This is a schematic diagram of the specific structure of the automatic quick-release testing machine clamp of this utility model.

[0011] In the figure: 1-Testing machine clamping body; 11-"U" groove; 12-First push sleeve mounting hole; 13-Axis through hole; 14-Slanted groove; 2-Locking sleeve; 21-Annular groove; 3-Locking piece; 31-Locking piece inner hole; 41-First push sleeve; 411-First push boss; 412-First push sleeve inner hole; 42-Second push sleeve; 421-Second push boss; 422-Second push sleeve inner hole; 43-Hydraulic cylinder; 44-Hydraulic cylinder telescopic rod; 45-Pull rod; 5-Steel cable; 6-Sensor. Detailed Implementation

[0012] To make the technical problem to be solved, the technical solution, and the beneficial effects of this utility model clearer, this utility model will be further described in detail. It should be understood that the specific embodiments described herein are only for explaining this utility model and are not intended to limit this utility model.

[0013] Example 1: Manually disassembled steel strand clamp like Figures 1 to 6 As shown, this embodiment provides a manually disassembled steel strand clamp, which mainly includes two test clamping bodies 1 arranged opposite to each other. The test clamping body 1 has a cavity machined inside, and a "U"-shaped groove 11 is opened on its side leading to the cavity. The bottom of the cavity has an oblique groove 14 that matches the cross section of the locking piece 3.

[0014] The core clamping part of the fixture consists of a locking sleeve 2 and locking plates 3. Locking plates 3 can be 3, 4, 5, or 6 pieces. In this embodiment, the locking plates 3 are preferably a three-piece structure with a trapezoidal cross-section, collectively forming a locking plate inner hole 31 through which the steel cable 5 passes. The locking plates 3 are installed inside the locking sleeve 2, and then the entire assembly is inserted into the cavity of the testing machine fixture 1 through the "U"-shaped groove 11. During the tensile test, the steel cable 5 is pulled by the force, causing the locking plates 3 to become increasingly tighter under the action of the inclined surface of the inclined groove 14, thereby achieving reliable clamping.

[0015] To achieve rapid disassembly, the key feature of this embodiment is the inclusion of a screw-type pusher assembly. A first pusher sleeve mounting hole 12 is provided near the opening of the testing machine fixture 1, with an internal thread connecting it to a first pusher sleeve 41. The first pusher sleeve 41 has a central inner hole 412 for the steel cable 5 to pass through, and an annular first pusher boss 411 is designed at its end facing the fixture. An annular groove 21 is provided on the locking sleeve 2, and the outer diameter of the first pusher boss 411 matches the inner diameter of the annular groove 21 on the locking sleeve 2.

[0016] The work process is as follows: After the steel strand tensile test is completed, the clamp is in the locked state. At this time, the operator only needs to use a tool or manually tighten the first push sleeve 41 to move it towards the clamp. The first push boss 411 then moves forward and presses against the end face of the locking plate sleeve 2 or the locking plate 3. Continue to tighten, and the axial thrust generated by the first push sleeve 41 can overcome the friction between the locking plate and the inclined groove, smoothly pushing the entire clamp (locking plate sleeve 2 and locking plate 3) out of the "U" groove 11, completing the disassembly. The whole process is labor-saving, quick, and requires no hammering, protecting the equipment and personal safety.

[0017] Example 2: Automatic disassembly type steel strand clamp like Figures 7 to 9 As shown, this embodiment provides an automated disassembly steel strand clamp with a higher degree of automation. Its basic structure is the same as that of Embodiment 1, including a test machine clamp body 1 with a "U"-shaped groove 11 and a bottom inclined groove 14, and a clamping part composed of a locking sleeve 2 and 3-6 locking plates 3.

[0018] The pusher assembly in this embodiment is hydraulically driven and is the core component for automatic disassembly. This assembly includes a hydraulic cylinder 43, a hydraulic cylinder telescopic rod 44, a pull rod 45, and a second pusher sleeve 42. The hydraulic cylinder 43 is fixedly installed at the tail of the testing machine fixture 1. The hydraulic cylinder telescopic rod 44 is connected to one end of a pull rod 45 that passes through an axial through hole 13, and the other end of the pull rod 45 is connected to the second pusher sleeve 42. The second pusher sleeve 42 has a second pusher boss 421 at one end near the fixture, and a second pusher sleeve inner hole 422 in the middle for the steel cable 5 to pass through. In the initial (clamping) state, the second pusher boss 421 abuts against the end of the locking piece 3 but does not apply any pushing force.

[0019] The work process is as follows: After the tensile test, the operator activates the hydraulic cylinder 43 via the control panel. The cylinder telescopic rod 44 retracts, pulling the second push sleeve 42 away from the clamp via the pull rod 45. Since the second push boss 421 abuts against the end face of the locking plate 3, this action effectively provides a reverse support point for the second push sleeve 42. When the hydraulic cylinder 43 continues to operate, its reaction force pushes the entire testing machine clamp body 1 backward relative to the clamp, equivalent to pushing the clamp out of the "U" groove. This process requires no manual intervention and can be completed with a single button operation, resulting in extremely high disassembly efficiency, making it particularly suitable for use in laboratories conducting automated testing or frequent high-strength tests.

[0020] In addition, in both embodiments of this application, sensors 6 can be connected to the upper and lower sides of the steel cable 5. When the tested steel cable breaks, the sensor is used to detect the tension and displacement in real time. Its core function is to immediately command the equipment to stop stretching when the steel cable breaks, thereby achieving rapid safety protection, and thus ensuring that complete test data is obtained and protecting the precision of the equipment.

Claims

1. A quick-release steel strand clamp, comprising two test clamp bodies arranged opposite each other, wherein the test clamp body (1) has a cavity inside, a clamp is disposed in the cavity, and a "U"-shaped groove (11) is provided on the side of the test clamp body for the clamp to pass through, characterized in that: The fixture includes a locking sleeve (2) and a locking piece (3). The locking piece (3) is fitted in the locking sleeve. The cross-section of the locking piece is trapezoidal. The locking piece is provided with an inner hole (31) for the steel cable to pass through. The testing machine fixture is also provided with a push-pull assembly near the opening. The push-pull assembly is used to quickly disassemble the fixture after the steel strand test is completed.

2. The quick-release steel strand clamp according to claim 1, characterized in that: The push assembly is a screw-type first push sleeve (41). The test machine fixture has a first push sleeve mounting hole (12) near the opening. The first push sleeve (41) has a first push boss (411) at the end near the fixture. The locking sleeve (2) has an annular groove (21). The outer diameter of the first push boss (411) matches the inner diameter of the annular groove (21) on the locking sleeve (2). The first push sleeve (41) also has a first push sleeve inner hole (412) in the middle for the steel cable (5) to pass through.

3. The quick-release steel strand clamp according to claim 1, characterized in that: The push assembly includes a second push sleeve (42), a hydraulic cylinder (43), a hydraulic cylinder telescopic rod (44), and a pull rod (45). The hydraulic cylinder telescopic rod (44) is connected to the hydraulic cylinder (43) and installed at the tail of the test machine fixture. The test machine fixture has an axial through hole (13). The pull rod (45) slides through the axial through hole (13). One end of the pull rod (45) is connected to the hydraulic cylinder telescopic rod (44), and the other end is connected to the second push sleeve (42). The second push sleeve (42) has a second push boss (421) at the end near the fixture. The second push boss (421) is abutted against the locking piece (3). The second push sleeve (42) also has a second push sleeve inner hole (422) in the middle for the steel cable (5) to pass through.

4. The quick-release steel strand clamp according to claim 2, characterized in that: Sensors (6) are connected to the upper and lower sides of the steel cable.

5. The quick-release steel strand clamp according to claim 3, characterized in that: Sensors (6) are connected to the upper and lower sides of the steel cable.

6. The quick-release steel strand clamp according to claim 4 or 5, characterized in that: The bottom of the cavity of the test machine clamp is provided with an oblique groove (14) for accommodating the locking piece.

7. The quick-release steel strand clamp according to any one of claims 1-5, characterized in that: The locking piece (3) consists of 3 to 6 pieces.

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