Reinforcing steel bar testing machine

Abstract

The invention provides a steel bar testing machine which comprises a base box and a supporting mechanism, and the supporting mechanism comprises two moving units arranged on the base box in a bilateral symmetry mode, two clamping units arranged on the two moving units correspondingly and an overturning unit arranged in the base box. The invention relates to the technical field of reinforcing steel bar testing equipment. The clamping unit can firmly fix the left point and the right point of a reinforcing steel bar. After a forward bending test is carried out, the overturning unit arranged in the base box can drive the two clamping units to overturn, so that the bent V-shaped reinforcing steel bar is directly driven to carry out a reverse bending test, and a sample does not need to be detached from a testing machine and then placed again. By means of the design, sample position deviation caused by repeated manual operation is avoided, the consistency of stress points and bending moment distribution of the reinforcing steel bars in forward and reverse bending tests is guaranteed, and therefore the accuracy and continuity of test results are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of steel bar testing equipment, in particular to a steel bar testing machine. Background Art

[0002] In the field of construction engineering, steel bars are key load-bearing components, and their bending performance is directly related to the safety and stability of the structure. In order to evaluate the bending deformation capacity and crack resistance of steel bars, they need to be subjected to rigorous bending tests.

[0003] Existing rebar testing equipment typically requires placing the specimen on its support device during a bending test. A forward bending test is then performed. After the forward bending test is completed, the specimen must be removed and replaced on the equipment for a reverse bending test. Because it's difficult to precisely position the specimen in the exact same position during the two placements, slight positional deviations are inevitable. This deviation causes the specimen's stress and deformation state during the reverse bending test to differ from that during the forward bending test, affecting the accuracy and repeatability of the test results and making it difficult to accurately assess the bidirectional bending performance of rebar in practical applications. Summary of the Invention

[0004] The present invention aims to provide a rebar testing machine that can solve the problem of existing rebar testing equipment that, when performing a bending test, typically requires placing a specimen on the testing equipment's support device, then performing a forward bending test. After completing the forward bending test, the specimen must be removed and then placed back on the equipment for a reverse bending test. Because the specimen is difficult to precisely position in the same location during the two placement processes, slight positional deviations are inevitable.

[0005] The present invention provides a steel bar testing machine, comprising a base box and a supporting mechanism, wherein two openings are provided on the top of the base box, and a supporting mechanism is provided on the top of the base box for supporting the steel bars so as to perform a bending test, wherein the supporting mechanism comprises two movable units symmetrically arranged on the base box, two clamping units respectively arranged on the two movable units, and a flipping unit arranged inside the base box, wherein the flipping unit is used to drive the above-mentioned two clamping units to flip, thereby performing continuous forward and reverse bending tests on the steel bars.

[0006] Preferably, the movable unit includes a mounting seat, a driving cylinder, a supporting shell, a movable plate, a rotating shaft, a concave frame and an inner frame, the mounting seat is fixedly arranged on the outer top of the supporting box, the driving cylinder is fixedly arranged on one side of the mounting seat, and the driving end of the driving cylinder moves through the mounting seat, the supporting shell is fixedly arranged on the driving end of the driving cylinder, the movable plate is fixedly arranged on the right side of the supporting shell, the supporting shell and the movable plate move through one of the openings, the rotating shaft is connected to the movable plate through a bearing, the concave frame is fixedly connected to the other end of the rotating shaft, the inner frame is fixedly arranged on the inner side of the concave frame, and the clamping unit is rotatably connected to the inner side of the inner frame.

[0007] Preferably, the clamping unit includes a movable frame, a movable shaft, a lower clamping seat, a screw, an upper clamping seat and two limit rods. Movable shafts are fixedly provided on the left and right sides of the movable frame. The movable shaft is connected to the left and right sides of the inner frame through bearings. The lower clamping seat is fixedly provided on the bottom of the movable frame. A threaded hole is provided on the top of the movable frame, and a screw is threadedly connected to the threaded hole. The top of the upper clamping seat is connected to the bottom end of the screw through a bearing. The two limit rods movably pass through the top of the movable frame, and the bottom ends of the two limit rods are fixedly connected to the top of the upper clamping seat. The flipping unit is provided in the base box, and the flipping unit is connected to the rotating shaft.

[0008] Preferably, the flip unit includes two bearing seats, a two-way telescopic tube, a motor, a first transmission member and a second transmission member. The two bearing seats are fixedly arranged in the base box, the two-way telescopic tube is connected to the two bearing seats, the motor is fixedly arranged on the top outside the base box, and the driving end of the motor moves through the top of the base box. The first transmission member is provided on the driving end of the motor and the outer wall of the two-way telescopic tube. One end of the two-way telescopic tube is connected to the movable plate through a bearing, and one end of the two-way telescopic tube and one end of the rotating shaft are provided with a second transmission member. The second transmission member is located in the support shell.

[0009] Preferably, the two-way telescopic tube includes a two-way outer tube, two groups of moving blocks and two moving inner rods. The outer wall of the two-way outer tube is interference fit with the inner rings of the two bearing seats. The inner wall of the two-way outer tube is provided with two groups of slideways. The two groups of moving blocks are respectively slidably connected to the two groups of slideways. The two moving inner rods are respectively fixed between the two groups of moving blocks, and the two moving inner rods are respectively movable through the left and right sides of the two-way outer tube. The moving inner rods are connected to the moving plate through bearings.

[0010] Preferably, the first transmission member includes a first bevel gear and a second bevel gear, the first bevel gear is fixedly arranged on the driving end of the motor, the second bevel gear is fixedly arranged on the outer wall of the double-pass outer tube, and the second bevel gear is meshed with the first bevel gear.

[0011] Preferably, the second transmission member includes a first sprocket, a second sprocket and a chain, the first sprocket is fixedly arranged at one end of the movable inner rod, the second sprocket is fixedly arranged at one end of the rotating shaft, and the second sprocket is connected to the first sprocket through a chain.

[0012] Preferably, the support mechanism further comprises two positioning units for improving stability when performing a bending test on the steel bars, and the two positioning units respectively correspond to the inner frames in the two moving units.

[0013] Preferably, the positioning unit includes an arc-shaped support seat, two slide rails, two sliders, a connecting plate, a connecting seat, a support platform, a locking cylinder and a locking block, the top and bottom of the inner frame are fixedly provided with an arc-shaped support seat, and a positioning hole is opened on the arc-shaped support seat, the two slide rails are fixedly provided on the top of the base box, the two sliders are slidably connected to the two slide rails respectively, the connecting plate is fixedly provided on the top of the two sliders, the connecting plate and the movable plate are connected through the connecting seat, the support platform is fixedly provided on the top of the connecting plate, and the support platform and the arc-shaped support seat match each other, the locking cylinder is fixedly provided on the bottom of the connecting plate, and a penetrating placement hole is opened in the connecting plate and the support platform, the locking block is fixedly provided at the driving end of the locking cylinder, the locking block is located in the placement hole and matches the positioning hole of the arc-shaped support seat.

[0014] Preferably, a ground rail is fixedly provided at the bottom of the base box, and the bottom of the movable plate is slidably connected to the ground rail.

[0015] The present invention provides a steel bar testing machine through improvements. Compared with the prior art, it has the following improvements and advantages: the clamping unit in the present invention can firmly fix the left and right points of the steel bar. After the forward bending test, the flip unit arranged inside the base box can drive the two clamping units to flip, thereby directly driving the V-shaped steel bar after bending to perform a reverse bending test, without the need to remove the sample from the testing machine and replace it. This design avoids the deviation of the sample position caused by multiple manual operations, ensures the consistency of the force point and bending moment distribution of the steel bar in the forward and reverse bending tests, and thus improves the accuracy and continuity of the test results. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the specific embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0017] Figure 1 It is a schematic diagram of the axonometric structure of the present invention;

[0018] Figure 2 It is a schematic diagram of the isometric structure of the concave frame, inner frame and clamping unit of the present invention;

[0019] Figure 3 Schematic diagram of the axonometric structure of the clamping unit of the present invention;

[0020] Figure 4 It is a schematic diagram of the axonometric structure of the screw rod, the upper clamping seat and the limiting rod of the present invention;

[0021] Figure 5 This is a schematic diagram of the main structure of the present invention;

[0022] Figure 6 This is a schematic diagram of the main structure of the bidirectional telescopic tube of the present invention;

[0023] Figure 7 is a side structural schematic diagram of the second transmission member of the present invention;

[0024] Figure 8 This is a schematic diagram of the axonometric structure of the positioning unit of the present invention;

[0025] Figure 9 This is a schematic diagram of the main structure of the connecting plate, support platform, locking cylinder and locking block of the present invention;

[0026] Figure 10 Schematic diagram of the structure of the steel bar of the present invention during the forward bending test.

[0027] Description of reference numerals:

[0028] 1. Base box; 2. Mobile unit; 21. Mounting seat; 22. Driving cylinder; 23. Support shell; 24. Mobile plate; 25. Rotating shaft; 26. Concave frame; 27. Inner frame; 28. Ground rail; 3. Clamping unit; 31. Movable frame; 32. Movable shaft; 33. Lower clamping seat; 34. Screw; 35. Upper clamping seat; 36. Limit rod; 4. Flip unit; 41. Bearing seat; 42. Two-way telescopic tube; 42-1. Two-way outer tube; 42- 2. Moving block; 42-3. Moving inner rod; 43. Motor; 44. First transmission member; 44-1. First bevel gear; 44-2. Second bevel gear; 45. Second transmission member; 45-1. First sprocket; 45-2. Second sprocket; 45-3. Chain; 5. Positioning unit; 51. Arc-shaped support seat; 52. Slide rail; 53. Slider; 54. Connecting plate; 55. Connecting seat; 56. Support platform; 57. Locking cylinder; 58. Locking block. DETAILED DESCRIPTION

[0029] The following will clearly and completely describe the technical solutions of the present invention in conjunction with the embodiments. Obviously, the embodiments described are only some embodiments of the present invention, not all 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.

[0030] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" and the like to indicate directions or positional relationships based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operate in a specific direction, and therefore should not be understood as limiting the present invention.

[0031] In the description of the present invention, it should be understood that the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more features. In the description of the present invention, "multiple" means two or more, unless otherwise clearly and specifically defined. In addition, the terms "installed", "connected", and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be a communication between the two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to the specific circumstances.

[0032] See also Figure 1-10 The present invention provides a technical solution: a steel bar testing machine, comprising a base box 1 and a support mechanism, the top of the base box 1 is provided with two openings, the base box 1 is used to support and accommodate the support mechanism, the top of the base box 1 is provided with a support mechanism for supporting the steel bar to perform a bending test, the support mechanism comprises two movable units 2 which are symmetrically arranged on the base box 1, the two symmetrical movable units 2 are adjustable and can be adjusted in position according to the length of the steel bar to be tested, two clamping units 3 are respectively arranged on the two movable units 2 and a flip unit 4 is arranged inside the base box 1, the two clamping units 3 are located on the left and right sides, and are used to fix two points on the left and right of the steel bar to be tested, thereby increasing the stability of the steel bar during the test and providing support for the subsequent flipping of the steel bar, the flip unit 4 is used to drive the above-mentioned two clamping units 3 to flip, thereby performing continuous forward and reverse bending tests on the steel bar, the flip unit 4 can flip the steel bar after the forward bending test to perform a reverse bending test, and can ensure that the steel bar is always under force in one position during the test, thereby avoiding the position deviation of the sample caused by the steel bar being removed from the testing machine and then placed again.

[0033] Specifically, the mobile unit 2 includes a mounting base 21, a driving cylinder 22, a support shell 23, a moving plate 24, a rotating shaft 25, a concave frame 26 and an inner frame 27. The mounting base 21 is fixedly arranged on the top outside the support box, the driving cylinder 22 is fixedly arranged on one side of the mounting base 21, and the driving end of the driving cylinder 22 is movable through the mounting base 21. The mounting base 21 provides support force for the installation of the driving cylinder 22, and the driving end of the driving cylinder 22 can be extended and retracted through the mounting base 21. The support shell 23 is fixedly arranged on the driving end of the driving cylinder 22. The support shell 23 is used to accommodate some components of the flipping mechanism. The moving plate 24 is fixedly arranged on the right side of the support shell 23. The support shell 23 and the movable plate 24 are movable through one of the openings, and the support shell 23 and the movable plate 24 can move horizontally and linearly within the opening under the drive cylinder 22. The rotating shaft 25 is connected to the movable plate 24 by a bearing. The concave frame 26 is fixedly connected to the other end of the rotating shaft 25. The inner frame 27 is fixedly arranged on the inner side of the concave frame 26. The concave frame 26 is used to connect the rotating shaft 25 and the inner frame 27. The inner frame 27 is used to provide support for the clamping unit 3. The clamping unit 3 is rotatably connected to the inner side of the inner frame 27. When the steel bar is placed between the clamping units 3 and fixed, the pressure head of the test device will apply downward pressure to the steel bar, causing it to bend and deform. At this time, the rotation ability of the clamping unit 3 allows the clamping unit 3 to rotate synchronously with the bending of the steel bar, thereby ensuring that the steel bar can smoothly reach the predetermined bending angle. This avoids stress concentration or slippage caused by the obstruction of the clamping unit 3 during the bending process. The clamping units 3 of the two moving units 2 can move linearly toward or away from each other under the drive of their respective driving cylinders 22, thereby adapting to steel bars to be tested of different lengths.

[0034] Specifically, the clamping unit 3 includes a movable frame 31, a movable shaft 32, a lower clamping seat 33, a screw 34, an upper clamping seat 35 and two limit rods 36. The movable shaft 32 is fixedly provided on the left and right sides of the movable frame 31. The movable shaft 32 is connected to the left and right sides of the inner frame 27 through bearings. The movable frame 31 can be rotated in the inner frame 27 through the movable shaft 32. The lower clamping seat 33 is fixedly provided at the bottom of the movable frame 31. The lower clamping seat 33 is fixed and does not move. A threaded hole is provided on the top of the movable frame 31, and a threaded hole is connected to the inner thread of the threaded hole. The screw 34 can be spirally rotated in the threaded hole. The top of the upper clamping seat 35 is connected to the bottom end of the screw 34 through a bearing. The two limit rods 36 are movable through the top of the movable frame 31, and the bottom ends of the two limit rods 36 are fixedly connected to the top of the upper clamping seat 35. The two limit rods 36 are respectively located on both sides of the screw 34. The flip unit 4 is arranged in the base box 1, and the flip unit 4 is connected to the rotating shaft 25. The flip unit 4 is used to provide rotational power for the rotating shaft 25, so that the clamping unit 3 drives the steel bar to flip.

[0035] When a rebar needs to be clamped, the two ends of the rebar are first placed on the lower clamping seats 33 of the two clamping units 3. Next, the worker performs the clamping operation by rotating the screw 34 downward. During the rotation of the screw 34, since the screw 34 is connected to the upper clamping seat 35 via a bearing, the two limit rods 36 precisely limit the movement of the upper clamping seat 35, so that the upper clamping seat 35 can only move linearly along the axis of the screw 34 and cannot rotate or deviate. As the screw 34 continues to rotate and move downward, the upper clamping seat 35 gradually approaches the rebar and eventually firmly fixes the rebar to the lower clamping seat 33. At this point, the rebar is tightly clamped by the upper and lower clamping seats 33, ready for the subsequent bending test.

[0036] Specifically, the flip unit 4 includes two bearing seats 41, a two-way telescopic tube 42, a motor 43, a first transmission member 44 and a second transmission member 45. The two bearing seats 41 are fixedly arranged in the base box 1, and the two-way telescopic tube 42 is connected to the two bearing seats 41. The bearing seats 41 provide support for the two-way telescopic tube 42, and the two-way telescopic tube 42 can rotate in the bearing seats 41. The motor 43 is fixedly arranged on the top outside the base box 1, and the driving end of the motor 43 is movable through the top of the base box 1. The first transmission member 44 is provided on the driving end of the motor 43 and the outer wall of the two-way telescopic tube 42. The motor 43 can transmit the rotational power to the two-way telescopic tube 42 through the first transmission member 44, and the two-way telescopic tube 42 can then rotate. The ends are connected to the movable plate 24 through bearings, one end of the two-way telescopic tube 42 can rotate within the movable plate 24, and the two ends of the two-way telescopic tube 42 can be telescoped and move with their corresponding movable plates 24 respectively. One end of the two-way telescopic tube 42 and one end of the rotating shaft 25 are provided with a second transmission member 45, and the second transmission member 45 is located in the supporting shell 23. The two-way telescopic tube 42 can continue to transmit the rotational power to the rotating shaft 25 through the second transmission member 45, so that the rotating shaft 25 rotates, and then drives the clamping unit 3 and the steel bar to flip over. There are two second transmission members 45, and the two second transmission members 45 are set on the left and the right, corresponding to the two movable units 2, and provide rotational power to the rotating shaft 25 in the two movable units 2 respectively.

[0037] Specifically, the two-way telescopic tube 42 includes a two-way outer tube 42-1, two groups of moving blocks 42-2 and two moving inner rods 42-3. The outer wall of the two-way outer tube 42-1 is interference fit with the inner rings of the two bearing seats 41. The inner wall of the two-way outer tube 42-1 is provided with two groups of slides. The two groups of moving blocks 42-2 are respectively slidably connected to the two groups of slides. The two moving inner rods 42-3 are respectively fixedly arranged between the two groups of moving blocks 42-2, and the two moving inner rods 42-3 are respectively movable through the left and right sides of the two-way outer tube 42-1. The moving inner rods 42-3 are connected to the moving plate 24 through bearings.

[0038] When the movable plate 24 moves driven by the driving cylinder 22, the movable inner rod 42-3 can stably extend and retract on the slide inside the double-way outer tube 42-1 through the movable block 42-2, and when the double-way outer tube 42-1 rotates, due to the sliding connection between the movable block 42-2 and the slide, the two movable inner rods 42-3 will also rotate synchronously, so that the rotational power of the double-way outer tube 42-1 can always be stably transmitted to the rotating shaft 25 through the second transmission member 45.

[0039] Specifically, the first transmission member 44 includes a first bevel gear 44-1 and a second bevel gear 44-2. The first bevel gear 44-1 is fixedly arranged on the driving end of the motor 43, and the second bevel gear 44-2 is fixedly arranged on the outer wall of the two-way outer tube 42-1, and the second bevel gear 44-2 is engaged with the first bevel gear 44-1. The first bevel gear 44-1 and the second bevel gear 44-2 are used to transmit the rotational power of the motor 43 to the two-way telescopic tube 42.

[0040] Specifically, the second transmission member 45 includes a first sprocket 45-1, a second sprocket 45-2 and a chain 45-3. The first sprocket 45-1 is fixedly arranged at one end of the movable inner rod 42-3, and the second sprocket 45-2 is fixedly arranged at one end of the rotating shaft 25. The second sprocket 45-2 is connected to the first sprocket 45-1 through the chain 45-3. The first sprocket 45-1 and the second sprocket 45-2 are arranged horizontally and parallel. When the movable inner rod 42-3 rotates, it can drive the first sprocket 45-1 to rotate. The first sprocket 45-1 can drive the second sprocket 45-2 to rotate through the chain 45-3, so that the rotating shaft 25 drives the clamping unit 3 and the steel bar to flip.

[0041] Specifically, the support mechanism further includes two positioning units 5 for improving stability when performing a bending test on the steel bars. The two positioning units 5 correspond to the inner frames 27 in the two moving units 2 respectively.

[0042] Specifically, the positioning unit 5 includes an arc-shaped support seat 51, two slide rails 52, two sliders 53, a connecting plate 54, a connecting seat 55, a support platform 56, a locking cylinder 57 and a locking block 58. The outer top and bottom of the inner frame 27 are fixedly provided with an arc-shaped support seat 51, and a positioning hole is provided on the arc-shaped support seat 51. The center of the arc-shaped support seat 51 coincides with the center point of the inner frame 27 to ensure that the arc-shaped support seat 51 can perform circular motion around the center of the inner frame 27 during the rotation of the inner frame 27, thereby always maintaining its relative position with the inner frame 27 unchanged. After the inner frame 27 is flipped 90 degrees, the upper and lower arc-shaped support seats 51 can still be in the same position after being swapped, ensuring that after the inner frame 27 is flipped, it can maintain good supporting force when the reverse bending test of the steel bar is carried out. The two slide rails 52 are fixedly provided on the outer top of the base box 1, and the two sliders 53 is slidably connected to the two slide rails 52 respectively, and the connecting plate 54 is fixedly arranged on the top of the two sliders 53. The connecting plate 54 and the movable plate 24 are connected by a connecting seat 55. The support platform 56 is fixedly arranged on the top of the connecting plate 54, and the support platform 56 matches the arc-shaped support seat 51. The support platform 56 can always be aligned with the arc-shaped support seat 51 on the inner frame 27 and effectively support it. The locking cylinder 57 is fixedly arranged at the bottom of the connecting plate 54. A through placement hole is provided in the connecting plate 54 and the support platform 56. The locking block 58 is fixedly arranged at the driving end of the locking cylinder 57. The locking block 58 is located in the placement hole and matches the positioning hole of the arc-shaped support seat 51. During the bending test, the locking block 58 is located in the positioning hole. When the clamping unit 3 and the steel bar are flipped, the locking block 58 is located in the placement hole, releasing the limit on the arc-shaped support seat 51.

[0043] When moving, the movable plate 24 can drive the connecting plate 54 to move synchronously in the slide rail 52 through the connecting seat 55, ensuring that the support platform 56 is always in the same position as the arc-shaped support seat 51 on the inner frame 27, ensuring that the support platform 56 always supports the arc-shaped support seat 51, thereby ensuring stability during the bending test. At the same time, during the test, the driving end of the locking cylinder 57 will extend, thereby driving the locking block 58 through the placement hole into the positioning hole of the arc-shaped support seat 51, fixing the arc-shaped support seat 51, and further improving the stability during the bending test.

[0044] Specifically, a ground rail 28 is fixedly provided at the bottom of the base box 1, and the bottom of the movable plate 24 is slidingly connected to the ground rail 28. The movable plate 24 can move back and forth along the ground rail 28, thereby driving the components connected to it, such as the rotating shaft 25, the connecting plate 54, and the support platform 56, to move synchronously. The ground rail 28 provides reliable support and guidance for the movable plate 24.

[0045] Working Principle: During a rebar bending test, the rebar is first placed between the two clamping units 3. The drive cylinder 22 is then activated, driving the movable plate 24, inner frame 27, and clamping units 3 to move laterally and linearly across the opening in the base box 1. Driven by their respective drive cylinders 22, the clamping units 3 of the two movable units 2 move toward each other, approaching the rebar until it is positioned between the two clamping units 3.

[0046] Simultaneously, the movable inner rod 42-3 follows the movable plate 24, stably extending and retracting along the slideway within the dual-pass outer tube 42-1. This ensures that the rotational force of the dual-pass outer tube 42-1 is stably transmitted to the rotating shaft 25 via the second transmission member 45, thus ensuring the proper operation of the subsequent flipping operation. Furthermore, during the movement of the movable plate 24, the connecting seat 55 synchronously drives the slider 53 and the support platform 56 within the slide rail 52, ensuring that the support platform 56 always provides sufficient support for the inner frame 27.

[0047] After the left and right ends of the steel bar are respectively between the two clamping units 3, the driving cylinder 22 stops working and the two ends of the steel bar are placed on the lower clamping seats 33 of the two clamping units 3. The staff then rotates the screw 34 downward. Since the screw 34 is connected to the upper clamping seat 35 by a bearing, and the limit rod 36 restricts the movement of the upper clamping seat 35, the upper clamping seat 35 can only move linearly along the axis of the screw 34. As the screw 34 rotates and moves downward, the upper clamping seat 35 gradually approaches the steel bar and eventually firmly fixes the steel bar on the lower clamping seat 33, completing the clamping of the steel bar. The driving end of the locking cylinder 57 then extends, driving the locking block 58 through the placement hole and into the positioning hole of the arc support seat 51, fixing the arc support seat 51 and further improving the stability during the bending test. The test can then begin.

[0048] At the start of the test, the pressure head of the external testing device applies downward pressure to the rebar, causing it to bend. The rotational capability of the clamping unit 3 allows it to rotate synchronously with the bending of the rebar, ensuring that the rebar smoothly reaches the predetermined bending angle and avoiding stress concentration or slippage. When a reverse bend test is required, the locking cylinder 57 retracts the locking block 58, disengaging it from the arc-shaped clamping seat and releasing the restraint on the arc-shaped clamping seat.

[0049] The flipping unit 4, located inside the base box 1, then begins operating. The motor 43 transmits rotational power to the double-pass outer tube 42-1 via the first transmission member 44. The double-pass outer tube 42-1 then drives the movable inner rod 42-3 to rotate. Since the movable plate 24 is now fixed, the movable inner rod 42-3 does not extend or retract within the double-pass outer tube 42-1, but instead rotates in tandem with it. The movable inner rod 42-3 transmits rotational power to the rotating shaft 25 via the second transmission member 45, causing the rotating shaft 25 to rotate, thereby driving the two clamping units 3 and the rebar to flip. After the flipping is complete, the upper and lower arc-shaped clamping seats are also swapped. The locking cylinder 57 drives the locking block 58 upward into the positioning hole, and the reverse bending test can then be performed.

[0050] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the above embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A steel bar testing machine, characterized in that: The invention comprises a base box (1) and a supporting mechanism, wherein the top of the base box (1) is provided with two openings, and the top of the base box (1) is provided with a supporting mechanism for supporting steel bars so as to perform bending tests, wherein the supporting mechanism comprises two movable units (2) symmetrically arranged on the base box (1), two clamping units (3) respectively arranged on the two movable units (2), and a turning unit (4) arranged inside the base box (1), wherein the turning unit (4) is used to drive the two clamping units (3) to turn over, thereby performing continuous forward and reverse bending tests on the steel bars.

2. A steel bar testing machine according to claim 1, characterized in that: The mobile unit (2) comprises a mounting seat (21), a driving cylinder (22), a supporting shell (23), a moving plate (24), a rotating shaft (25), a concave frame (26) and an inner frame (27); the mounting seat (21) is fixedly arranged on the top of the supporting box; the driving cylinder (22) is fixedly arranged on one side of the mounting seat (21); and the driving end of the driving cylinder (22) is movable through the mounting seat (21); the supporting shell (23) is fixedly arranged on the driving cylinder (22) ), the movable plate (24) is fixedly arranged on the right side of the supporting shell (23), the supporting shell (23) and the movable plate (24) are movable through one of the openings, the rotating shaft (25) is connected to the movable plate (24) through a bearing, the concave frame (26) is fixedly connected to the other end of the rotating shaft (25), the inner frame (27) is fixedly arranged on the inner side of the concave frame (26), and the clamping unit (3) is rotatably connected to the inner side of the inner frame (27).

3. A steel bar testing machine according to claim 2, characterized in that: The clamping unit (3) comprises a movable frame (31), a movable shaft (32), a lower clamping seat (33), a screw (34), an upper clamping seat (35) and two limit rods (36). The movable shaft (32) is fixedly provided on both the left and right sides of the movable frame (31). The movable shaft (32) is connected to the left and right sides of the inner frame (27) through bearings. The lower clamping seat (33) is fixedly provided at the bottom of the movable frame (31). The top of the movable frame (31) is fixedly provided with a movable shaft (32). A threaded hole is provided on the top of the movable frame (31), and a screw rod (34) is threadedly connected to the threaded hole. The top of the upper clamping seat (35) is connected to the bottom end of the screw rod (34) through a bearing. The two limiting rods (36) are movably inserted into the top of the movable frame (31), and the bottom ends of the two limiting rods (36) are fixedly connected to the top of the upper clamping seat (35). The flip unit (4) is arranged in the base box (1), and the flip unit (4) is connected to the rotating shaft (25).

4. A steel bar testing machine according to claim 3, characterized in that: The flip unit (4) includes two bearing seats (41), a two-way telescopic tube (42), a motor (43), a first transmission member (44) and a second transmission member (45). The two bearing seats (41) are fixedly arranged in the base box (1). The two-way telescopic tube (42) is connected to the two bearing seats (41). The motor (43) is fixedly arranged on the top outside the base box (1), and the driving end of the motor (43) is movable through the top of the base box (1). The first transmission member (44) is arranged on the driving end of the motor (43) and the outer wall of the two-way telescopic tube (42). One end of the two-way telescopic tube (42) is connected to the movable plate (24) through a bearing. One end of the two-way telescopic tube (42) and one end of the rotating shaft (25) are provided with a second transmission member (45). The second transmission member (45) is located in the supporting shell (23).

5. A steel bar testing machine according to claim 4, characterized in that: The bidirectional telescopic tube (42) comprises a bidirectional outer tube (42-1), two groups of moving blocks (42-2) and two moving inner rods (42-3). The outer wall of the bidirectional outer tube (42-1) is interference-fitted with the inner rings of the two bearing seats (41). The inner wall of the bidirectional outer tube (42-1) is provided with two groups of slideways. The two groups of moving blocks (42-2) are respectively slidably connected to the two groups of slideways. The two moving inner rods (42-3) are respectively fixedly arranged between the two groups of moving blocks (42-2). The two moving inner rods (42-3) are respectively movable and penetrate the left and right sides of the bidirectional outer tube (42-1). The moving inner rods (42-3) are connected to the moving plate (24) via bearings.

6. A steel bar testing machine according to claim 5, characterized in that: The first transmission member (44) comprises a first bevel gear (44-1) and a second bevel gear (44-2); the first bevel gear (44-1) is fixedly arranged on the driving end of the motor (43); the second bevel gear (44-2) is fixedly arranged on the outer wall of the double-pass outer tube (42-1), and the second bevel gear (44-2) is meshed with the first bevel gear (44-1).

7. A steel bar testing machine according to claim 6, characterized in that: The second transmission member (45) comprises a first sprocket (45-1), a second sprocket (45-2) and a chain (45-3); the first sprocket (45-1) is fixedly arranged at one end of the movable inner rod (42-3); the second sprocket (45-2) is fixedly arranged at one end of the rotating shaft (25); and the second sprocket (45-2) and the first sprocket (45-1) are connected via the chain (45-3).

8. A steel bar testing machine according to claim 7, characterized in that: The support mechanism further comprises two positioning units (5) for improving stability when performing a bending test on a steel bar, and the two positioning units (5) respectively correspond to the inner frames (27) in the two moving units (2).

9. A steel bar testing machine according to claim 8, characterized in that: The positioning unit (5) comprises an arc-shaped support seat (51), two slide rails (52), two sliders (53), a connecting plate (54), a connecting seat (55), a supporting platform (56), a locking cylinder (57) and a locking block (58). The top and bottom of the inner frame (27) are fixedly provided with an arc-shaped support seat (51), and a positioning hole is provided on the arc-shaped support seat (51). The two slide rails (52) are fixedly provided on the top of the base box (1). The two sliders (53) are slidably connected to the two slide rails (52) respectively. The connecting plate (54) is fixedly provided on the two sliders ( 53), the connecting plate (54) and the movable plate (24) are connected via a connecting seat (55), the supporting platform (56) is fixedly arranged on the top of the connecting plate (54), and the supporting platform (56) matches the arc-shaped supporting seat (51), the locking cylinder (57) is fixedly arranged on the bottom of the connecting plate (54), and a placement hole is provided through the connecting plate (54) and the supporting platform (56), the locking block (58) is fixedly arranged on the driving end of the locking cylinder (57), the locking block (58) is located in the placement hole, and matches the positioning hole of the arc-shaped supporting seat (51).

10. A steel bar testing machine according to claim 9, characterized in that: A ground rail (28) is fixedly provided at the bottom of the base box (1), and the bottom of the movable plate (24) is slidably connected to the ground rail (28).

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