A fixture suitable for cantilever vibration test piece

Abstract

The present invention discloses a clamp suitable for a cantilever vibration test piece, comprising a clamp outer frame, a large wedge, a small wedge and a locking screw. The clamp outer frame is fixed on a vibration table, a rectangular groove is provided on the front end surface of the clamp outer frame, and one end of the cantilever vibration test piece is placed in the rectangular groove; the large wedge and the small wedge are both provided with an inclined surface with the same inclination angle, and the inclined surface of the large wedge and the inclined surface of the small wedge are closely fitted and installed in the rectangular groove to compress the cantilever vibration test piece, and the large wedge and the small wedge are installed with the rectangular groove as a transition fit in the width direction; a first through hole connected to the rectangular groove is provided on the rear end surface of the clamp outer frame, and a threaded through hole is provided on the large wedge. The cantilever vibration test piece is clamped and fixed by passing the locking screw through the first through hole of the clamp outer frame and screwing it into the threaded through hole of the large wedge. The clamp has a simple structure and reliable performance, and can complete the clamping and convenient disassembly of the cantilever vibration test piece through simple operation.

Description

Technical Field

[0001] The invention belongs to the technical field of clamps and relates to a clamp suitable for a cantilever vibration test piece. Background Art

[0002] A fixture is a device for fixing and positioning mechanical parts. In vibration tests, a fixture is required to fix the test piece to the vibration table to complete the test. Cantilever is a common loading form in vibration tests, which is common in vibration tests of research objects such as aircraft engine blades, as well as vibration fatigue tests. The existing technology generally uses screws to directly tighten the parts to be clamped. Figure 1 The figure shows the principle of a common vibration test fixture, which includes an upper fixture A and a lower fixture B. The lower fixture A is fixed on the vibration table, and the specimen C to be clamped is placed between the lower fixture B and the upper fixture A. The upper fixture A and the lower fixture B are connected by screws and a clamping force is applied to the specimen C to complete the clamping of the specimen.

[0003] The fixtures suitable for cantilever vibration tests in the prior art generally have the problems of cumbersome installation, poor clamping fit, easy to be biased, and unable to prevent loosening. Among them, in order to ensure a larger clamping force, a design of multiple bolts clamping together is generally adopted, so a lot of operations are required during clamping; at the same time, due to the large number of bolts, it is easy to have uneven tightening force of the bolts, resulting in uneven load distribution on the clamping surface of the specimen, and even skewed clamping; in addition, this technology uses screws to directly provide clamping force, which is easy to cause clamping failure due to loose threads, affecting the normal progress of the test. In summary, the prior art has certain shortcomings and needs further improvement. Summary of the invention

[0004] In order to solve the above technical problems, the purpose of the present invention is to provide a clamp suitable for a cantilever vibration test piece, which has a simple structure and reliable performance and can complete the clamping and convenient disassembly tasks of the cantilever vibration test piece through simple operations.

[0005] The present invention provides a clamp suitable for a cantilever vibration specimen, comprising: a clamp outer frame, a large wedge block, a small wedge block and a locking screw, the clamp outer frame is fixed on a vibration table, a front end surface of the clamp outer frame is provided with a rectangular groove, one end of the cantilever vibration specimen is placed in the rectangular groove; the large wedge block and the small wedge block are both provided with an inclined surface with the same inclination angle, the inclined surface of the large wedge block and the inclined surface of the small wedge block are tightly fitted and then installed in the rectangular groove to press the top surface of the cantilever vibration specimen, the large wedge block and the small wedge block are installed in a transition fit with the rectangular groove in the width direction; a first through hole connected to the rectangular groove is provided on the rear end surface of the clamp outer frame, a threaded through hole is provided on the large wedge block, and the cantilever vibration specimen is clamped and fixed by passing the locking screw through the first through hole of the clamp outer frame and screwing it into the threaded through hole of the large wedge block.

[0006] In the fixture suitable for cantilever vibration test piece of the present invention, the lengths of the large wedge block and the small wedge block are both smaller than the depth of the rectangular groove, and the depth of the rectangular groove is the distance from the front end surface of the fixture outer frame to the bottom of the rectangular groove.

[0007] In the fixture suitable for cantilever vibration test piece of the present invention, the fixture also includes a quick release tool, and the quick release tool includes a rectangular bottom plate, three edges of the rectangular bottom plate are provided with flanges, and the rectangular bottom plate is provided with a second through hole.

[0008] In the fixture suitable for cantilever vibration specimens of the present invention, after the test is completed, the locking screw is unscrewed, and the quick release tool is installed on the front end face of the fixture outer frame, so that the rectangular bottom plate fits with the front end face of the fixture outer frame, and the flange fits with the top face and two side faces of the fixture outer frame, and the locking screw is passed through the second through hole of the quick release tool and screwed into the threaded through hole of the large wedge block, and tightened until the large wedge block loosens, and the large wedge block, the small wedge block and the cantilever vibration specimen can be taken out, and the disassembly is completed.

[0009] In the fixture suitable for cantilever vibration test piece of the present invention, the fixture further comprises a spring washer and a gasket, the spring washer and the gasket are sequentially sleeved on the locking screw, and the gasket is in contact with the outer frame of the fixture.

[0010] In the fixture suitable for cantilever vibration test pieces of the present invention, the fixture outer frame is made of aluminum alloy and is in an inverted T shape as a whole. A mounting hole is provided at the bottom thereof and is fixedly mounted on the vibration table surface through the mounting hole and bolts.

[0011] In the fixture suitable for cantilever vibration test piece of the present invention, the rectangular grooves are all chamfered with arc transition.

[0012] In the fixture suitable for cantilever vibration test piece of the present invention, the large wedge block and the small wedge block are both made of steel, and all sides and vertices of the large wedge block and the small wedge block are chamfered.

[0013] The clamp of the present invention suitable for a cantilever vibration test piece has the following advantages:

[0014] 1. The clamp structure of the present invention can provide greater clamping force.

[0015] The clamp structure of the present invention includes a two-stage force amplification mechanism, namely, a thread and an inclined surface. The thread is used to convert the tightening torque into a force for the large wedge to move horizontally along the front and rear directions of the clamp outer frame. Restricted by the two side surfaces and the top surface of the rectangular groove of the clamp outer frame, the large wedge converts the horizontal force into a downward pressure on the small wedge through the inclined surface, and together with the lower surface in the rectangular groove, completes the clamping of the test piece.

[0016] 2. The clamp structure of the present invention has an anti-loosening function.

[0017] Mechanical vibration is a common cause of loosening of fastening structures, so the vibration test fixture needs to have good anti-loosening performance. The clamp of the present invention has a spring washer used in conjunction with a locking screw to prevent the locking screw from loosening during vibration. The large wedge block and the small wedge block transmit the clamping force through the inclined surface, and the designed inclined surface angle has a self-locking property, which can prevent loosening during the test; at the same time, due to the self-locking property of the structure, once clamped, the structure is not easy to loosen. In order to facilitate the disassembly of the test piece after the test, a quick-release tool is specially designed to reduce the difficulty of operation.

[0018] 3. The clamp structure of the present invention can achieve high-quality bonding of the test piece to be clamped with a simple structure and operation.

[0019] Except for the two bolts that fix the clamp frame to the vibration table, the actual loading operation for clamping the test piece in the structure of the present invention is only the tightening of the locking screws. There is no need to perform a large amount of repetitive and tedious screw tightening work. At the same time, the tightening torque can be set as needed. The two important movable parts in this structure, namely the large wedge block and the small wedge block, are restricted in their movement by the rectangular groove. During the clamping process, the large wedge block can only move horizontally along the front and rear directions of the clamp frame, and the small wedge block can only move vertically, which ensures that the direction of the clamping force is always vertically downward. Therefore, the clamping end of the specimen can fit well and avoid the phenomenon of uneven clamping load.

[0020] 4. The fixture structure of the present invention has a lighter weight and better durability

[0021] The clamp frame of the main body of the clamp of the present invention is made of aluminum alloy, which is light in weight and can effectively save the power of the vibration table; the large wedge block connected to the thread of the locking screw is made of steel, which can withstand a large load on the thread and will not fail even after repeated disassembly and assembly, thereby ensuring the durability of the clamp. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a structural schematic diagram of a fixture suitable for a cantilever vibration test piece of the present invention;

[0023] Figure 2 It is a front view of a fixture suitable for a cantilever vibration test piece of the present invention;

[0024] Figure 3 yes Figure 2 AA section view;

[0025] Figure 4 It is a schematic diagram of the structure of the quick release tool;

[0026] Figure 5 It is a schematic diagram of disassembly using a quick release tool;

[0027] Wherein: 1- fixture frame, 2- large wedge, 21- threaded through hole, 3- small wedge, 4- cantilever vibration specimen, 5- locking screw, 6- spring washer, 7- gasket, 8- rectangular groove, 9- quick release tool, 91- second through hole. DETAILED DESCRIPTION

[0028] like Figures 1 to 3 As shown, a clamp suitable for a cantilever vibration specimen of the present invention comprises: a clamp outer frame 1, a large wedge block 2, a small wedge block 3 and a locking screw 5. The clamp outer frame 1 is fixed on the vibration table, and a rectangular groove 8 is provided on the front end surface of the clamp outer frame 1, and one end of the cantilever vibration specimen 4 is placed in the rectangular groove 8. The large wedge block 2 and the small wedge block 3 are both provided with an inclined surface with the same inclination angle, and the inclined surface of the large wedge block 2 and the inclined surface of the small wedge block 3 are tightly fitted and installed in the rectangular groove 8 to press the top surface of the cantilever vibration specimen 4. The large wedge block 2 and the small wedge block 3 are installed with a transition fit with the rectangular groove 8 in the width direction, and the displacement of the large wedge block 2 and the small wedge block 3 in the horizontal direction is limited by the transition fit. A first through hole connected to the rectangular groove 8 is provided on the rear end face of the clamp outer frame 1, and a threaded through hole 21 is provided on the large wedge block 2. The cantilever vibration specimen 4 is clamped and fixed by passing the locking screw 5 through the first through hole of the clamp outer frame 1 and screwing it into the threaded through hole 21 of the large wedge block 2.

[0029] In a specific implementation, the clamp further includes a spring washer 6 and a gasket 7 , which are sequentially sleeved on the locking screw 5 , and the gasket 7 is in contact with the outer frame 1 of the clamp.

[0030] In specific implementation, the fixture outer frame 1 is made of aluminum alloy, and is in an inverted T shape as a whole, with a mounting hole at the bottom, which is fixedly mounted on the vibration table through the mounting hole and bolts. The rectangular grooves are all chamfered with arc transitions.

[0031] In a specific implementation, the large wedge block 2 and the small wedge block 3 are both made of steel, and all sides and vertices of the large wedge block 2 and the small wedge block 3 are chamfered.

[0032] In a specific implementation, the lengths of the large wedge block 2 and the small wedge block 3 are both smaller than the depth of the rectangular groove 8 , and the depth of the rectangular groove 8 is the distance from the front end surface of the clamp outer frame 1 to the bottom of the rectangular groove 1 .

[0033] like Figure 4 As shown, in a specific implementation, the clamp further includes a quick release tool 9, and the quick release tool 9 includes a rectangular bottom plate, three edges of the rectangular bottom plate are provided with flanges, and a second through hole 91 is provided on the rectangular bottom plate.

[0034] like Figure 5 As shown, the clamping and disassembly process of the fixture suitable for the cantilever vibration test piece of the present invention is as follows:

[0035] 1. Use two bolts to fix the fixture frame 1 to the surface of the vibration table;

[0036] 2. Place the cantilever vibration specimen 4 to be clamped horizontally into the rectangular groove 8 of the fixture outer frame 1, so that the lower end surface and the rear end surface of the cantilever vibration specimen 4 are closely fitted with the side wall of the rectangular groove 8;

[0037] 3. Place the small wedge block 3 into the rectangular groove 8 with the inclined surface facing upward and the thicker end facing inward. The bottom surface of the small wedge block 3 is tightly fitted with the cantilever vibration test piece 4, and the rear end surface and two side surfaces are tightly fitted with the inner wall of the rectangular groove 8;

[0038] 4. Insert the large wedge block 2 into the rectangular groove 8 with the inclined surface downward and the thinner end inward, so that the inclined surfaces of the large wedge block 2 and the small wedge block 3 fit closely, and the upper end surface and two side surfaces of the large wedge block 2 fit closely with the inner wall of the rectangular groove 8;

[0039] 5. Insert the spring washer 6 and the gasket 7 onto the locking screw 5 in sequence, and insert the locking screw 5 through the first through hole on the rear end face of the fixture outer frame 1, screw it into the threaded through hole 21 of the large wedge block 2, and tighten it until it is tightened to complete the clamping of the cantilever vibration specimen 4;

[0040] 6. After the test is completed, unscrew the locking screw 5 and install the quick release tool 9 on the front end face of the fixture outer frame 1, so that the rectangular bottom plate fits with the front end face of the fixture outer frame 1, and the flange fits with the top surface and two side surfaces of the fixture outer frame 1. Pass the locking screw 5 through the second through hole 91 of the quick release tool 9 and screw it into the threaded through hole 21 of the large wedge block 2. Tighten it until the large wedge block 2 loosens, then take out the large wedge block 2, the small wedge block 3 and the cantilever vibration specimen 4, and complete the disassembly.

[0041] The above description is only a preferred embodiment of the present invention and is not intended to limit the concept of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A fixture suitable for a cantilever vibration test piece, characterized in that: include: The outer frame of the clamp, the large wedge block, the small wedge block and the locking screw, the outer frame of the clamp is fixed on the vibration table, the front end surface of the outer frame of the clamp is provided with a rectangular groove, one end of the cantilever vibration specimen is placed in the rectangular groove; the large wedge block and the small wedge block are both provided with an inclined surface with the same inclination angle, and the inclined surface of the large wedge block and the inclined surface of the small wedge block are tightly fitted and installed in the rectangular groove to press the top surface of the cantilever vibration specimen, and the large wedge block and the small wedge block are installed in a transition fit with the rectangular groove in the width direction; the rear end surface of the outer frame of the clamp is provided with a first through hole connected to the rectangular groove, and the large wedge block is provided with a threaded through hole, and the cantilever vibration specimen is clamped and fixed by passing the locking screw through the first through hole of the outer frame of the clamp and screwing it into the threaded through hole of the large wedge block; The lengths of the large wedge block and the small wedge block are both smaller than the depth of the rectangular groove, and the depth of the rectangular groove is the distance from the front end surface of the fixture outer frame to the bottom of the rectangular groove; The clamp further comprises a quick-release tool, the quick-release tool comprising a rectangular bottom plate, flanges are arranged on three edges of the rectangular bottom plate, and a second through hole is arranged on the rectangular bottom plate; After the test is completed, unscrew the locking screw and install the quick release tool on the front end face of the fixture frame so that the rectangular bottom plate fits with the front end face of the fixture frame, and the flange fits with the top surface and two side surfaces of the fixture frame. Pass the locking screw through the second through hole of the quick release tool and screw it into the threaded through hole of the large wedge. Tighten it until the large wedge loosens, then take out the large wedge, small wedge and cantilever vibration specimen, and complete the disassembly.

2. The fixture for cantilever vibration test piece according to claim 1, characterized in that: The clamp also includes a spring washer and a gasket, which are sleeved on the locking screw in sequence, and the gasket is in contact with the outer frame of the clamp.

3. The fixture for cantilever vibration test piece according to claim 1, characterized in that: The outer frame of the clamp is made of aluminum alloy and is in an inverted T shape as a whole. A mounting hole is provided at the bottom of the clamp and the clamp is fixedly mounted on the vibration table surface through the mounting hole and bolts.

4. The fixture for cantilever vibration test piece according to claim 1, characterized in that: The rectangular grooves are all chamfered with arc transition.

5. The fixture for cantilever vibration test piece according to claim 1, characterized in that: The large wedge block and the small wedge block are both made of steel, and all sides and vertices of the large wedge block and the small wedge block are chamfered.

Images