Standard test piece vibration fatigue test fixture and installation method

Abstract

The application belongs to the technical field of vibration test, and particularly relates to a standard test piece vibration fatigue test clamp and a mounting method, which comprises a clamping body and a clamping plate, and the clamping plate is inserted into the clamping body; the clamping plate comprises a horizontal clamping plate, a vertical clamping plate, a columnar clamping plate and a mounting groove; the vertical clamping plate is connected to one long side of the horizontal clamping plate perpendicularly to form a T shape, the horizontal clamping plate is provided with a columnar clamping plate formed by protrusions on upper and lower plate surfaces, and the mounting groove is located on the upper plate surface of the horizontal clamping plate and extends from the side where the vertical clamping plate is located to the opposite side; the vertical clamping plate is provided with a reserved hole; the clamping body is provided with a T-shaped groove, the shape of the T-shaped groove is the same as the projection of the clamping plate along the insertion direction of the clamping plate, the clamping body is provided with a mounting hole which is adapted to the reserved hole and is in communication with the reserved hole; and when the clamping plate is inserted into the clamping body along the T-shaped groove, the mounting hole on the clamping body and the reserved hole on the clamping plate are connected through a bolt.

Description

Technical Field

[0001] This application belongs to the field of vibration testing technology, and specifically relates to a standard test piece vibration fatigue test fixture and installation method. Background Technology

[0002] Standard test specimens (hereinafter referred to as standard specimens) are commonly used to determine the mechanical properties of materials. In the field of dynamics, the vibration fatigue life, fatigue limit, and fatigue crack propagation of materials can all be measured by vibration fatigue tests on standard specimens.

[0003] Vibration fatigue testing of standard parts is mainly conducted by mounting the standard parts onto a vibration table using fixtures. The test results are affected by factors such as stress concentration, mean stress, notch effect, and surface condition. Therefore, the installation effect resulting from the fixture design significantly influences the vibration fatigue test results. Currently, vibration fatigue testing fixtures for standard parts can be divided into two types. One type consists of two pressure plates with bolt holes, connected by bolts, pressing the standard part between the two plates to ensure fixed boundary conditions and vibration transmission rate. However, during vibration fatigue testing, the pressure plates are compressed by the bolts, causing stress on the fixed section of the standard part, which can easily lead to stress concentration at the ends of the standard part, changing its stress state and altering the alternating stress during the test, thus affecting the vibration fatigue test results. The second type involves machining a certain number of through holes on the standard part and connecting it to a fixed fixture with bolts. This method cannot quantify the force at the bolt connection. If the bolt tightening force is too small, the bolts are prone to loosening, and the vibration transmission rate cannot be guaranteed. If the bolt tightening force is too large, it will cause stress concentration at the through hole attachments.

[0004] Furthermore, current vibration fatigue testing fixtures have fixed dimensions and are designed to fit existing standard parts. This results in poor versatility, poor compatibility with test pieces of varying dimensions, low accuracy, and difficulty in repeated application. Therefore, it is necessary to explore a new and effective vibration fatigue testing fixture and its installation method. Summary of the Invention

[0005] To address the aforementioned problems, this application provides a standard test specimen vibration fatigue testing fixture, comprising:

[0006] The clamp body and the clamp plate are inserted into the clamp body;

[0007] The pallet includes: horizontal pallets, vertical pallets, columnar pallets, and mounting slots;

[0008] The longitudinal plate is vertically connected to one long side of the transverse plate to form a T-shape. The upper and lower surfaces of the transverse plate protrude to form a columnar plate. The mounting groove is located on the upper surface of the transverse plate and extends from the side where the longitudinal plate is located to the opposite side. The longitudinal plate has pre-drilled holes.

[0009] The clamp body has a T-slot, the shape of which is the same as the projection of the card plate along the insertion direction of the card plate. The clamp body has mounting holes that are compatible with the reserved holes.

[0010] When the card plate is inserted into the clamping body along the T-slot, the mounting holes on the clamping body are connected to the reserved holes on the card plate by bolts.

[0011] Preferably, the card has a mounting ring on one side.

[0012] Preferably, the clamping body includes a base plate and an upper plate, a T-slot is located on the upper plate, the area of ​​the base plate is larger than that of the upper plate, the upper plate is mounted on the base plate, and the base plate has a through hole for fixed installation.

[0013] Preferably, the shape of the mounting groove is adapted to the standard part to be tested.

[0014] Preferably, the T-slot includes a longitudinal slot adapted to the longitudinal clamping plate and a transverse slot adapted to the transverse clamping plate, the transverse slot penetrating the side of the clamping body to expose the standard part to be tested.

[0015] Preferably, it also includes a card for filling the gap between the standard part to be tested and the mounting slot.

[0016] Preferably, the T-slot is continuous or partially continuous along the insertion direction of the card plate.

[0017] A method for installing a standard test specimen vibration fatigue test fixture, using the aforementioned standard test specimen vibration fatigue test fixture, includes the following steps:

[0018] Install one end of the standard part into the mounting slot of the card plate;

[0019] When the height of the standard part is less than the height of the mounting slot, install the card;

[0020] Insert the clamp plate containing the standard parts into the T-slot of the clamp body through the mounting ring, and connect the mounting holes on the clamp body with the reserved holes on the clamp plate through bolts;

[0021] Connect the fixture to the vibration table through the bottom through hole to complete the installation of the standard parts;

[0022] Determine the measurement and control points for the vibration fatigue test, connect the vibration control and data acquisition equipment, start the vibration table, and conduct the vibration fatigue test on the standard parts.

[0023] The advantages of this application include: by setting an installation groove on the clamping plate, the clamping end of the test piece fits tightly with the inner surface of the clamping plate installation groove; and by designing a T-shaped groove inside the clamping body, the clamping plate and the clamping body fit tightly together, thus achieving the fixation of the clamping body. This effectively avoids local stress concentration on the test piece caused by external clamping force, avoids fatigue damage and fatigue cracks at the clamping end, and ensures the reliability and stability of the vibration fatigue test process, as well as the validity and accuracy of the test results.

[0024] In addition, mounting holes are designed on the fixture body and reserved holes are designed on the clamping plate. The clamping plate is connected by bolts, which restricts the degree of freedom of the clamping plate in the T-slot and the direction perpendicular to the transverse slot. This will not cause adverse effects such as stress concentration on the test piece, while ensuring vibration transmission. The fixture has good stability.

[0025] Meanwhile, a columnar clamping plate is set on the clamping plate, which makes close contact with the concave arc groove of the clamping body, restricting the degree of freedom of the clamping plate and the transverse groove in the same direction. Compared with the traditional pressure plate bolt connection and the bolt connection with holes, it will not bring stress concentration and prestress to the standard parts, ensuring the effectiveness of fatigue test, while ensuring rigid connection and transfer rate, and further improving the stability of the fixture.

[0026] Furthermore, a card is designed between the clamping end of the standard part and the transverse groove. When the depth of the mounting groove is much greater than the thickness of the standard part, it can fill the gap and ensure that the surfaces of the standard part and the fixture are in close contact. At the same time, for vibration fatigue testing, it is necessary to repeat the vibration fatigue test multiple times in order to obtain the SN curve. It cannot be guaranteed that every standard part and the slot will be in complete close contact. The card can be used to fill the gaps of standard parts of different thicknesses, thus expanding the application range of the vibration fatigue testing fixture and making it more versatile.

[0027] Meanwhile, the present invention also provides a method for installing a vibration fatigue test fixture for standard test specimens. The test fixture is simple, the components are easy to disassemble and assemble, the vibration transmission characteristics are good, the efficiency of vibration fatigue testing is improved, and the authenticity and validity of vibration fatigue test results are guaranteed. Attached Figure Description

[0028] Figure 1 This is a schematic diagram of the overall structure of the vibration test fixture;

[0029] Figure 2 It is a three-dimensional drawing of the clamp;

[0030] Figure 3 It is an isometric side view of the clamping device;

[0031] Figure 4 It is a top view of the clamping device;

[0032] Figure 5 It is a section view of the clamping body (AA section).

[0033] Figure 6 It is a 3D diagram of the cardboard.

[0034] Figure 7 This is an isometric side view of the card plate;

[0035] Figure 8 It is a 3D image of the card;

[0036] Figure 9 This is an assembly diagram of the pallet and standard parts;

[0037] Figure 10 It is an assembly diagram of the pallet, standard parts and cards;

[0038] Figure 11 This is a schematic diagram of the assembly of the card plate, standard parts, cards and clamps. Detailed Implementation

[0039] To make the technical solution and advantages of this application clearer, the technical solution of this application will be described in a clearer and more complete manner below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are only some embodiments of this application, and are only used to explain this application, not to limit this application. It should be noted that, for ease of description, only the parts related to this application are shown in the accompanying drawings. Other related parts can be referred to the general design. In the absence of conflict, the embodiments and technical features in the embodiments of this application can be combined with each other to obtain new embodiments.

[0040] like Figures 1-11 As shown, this invention provides a standard component vibration fatigue testing fixture, including a fixture body 1, a clamping plate, a clip, and a standard component. The standard component is installed inside the clamping plate, which is installed inside the fixture body 1. The clamping plate has a mounting groove 26, and the clamping end of the standard component contacts and fits tightly against the surface of the groove. The fixture body 1 has a T-shaped groove 13, and the outer surface of the clamping plate contacts and fits tightly against the inner surface of the T-shaped groove 13. At the same time, the fixture body 1 and the clamping plate are connected by six bolt holes, which restrict the degree of freedom of the clamping plate along the direction of the T-shaped groove 13, thereby restricting the degree of freedom of the standard component along its width direction.

[0041] The fixture body 1 consists of a base plate 12 and an upper plate 14, which are integrally formed during machining. Four through holes are provided on the base plate 12, with their centers symmetrically distributed around the entire base plate 12. Bolts pass through these through holes and connect to the threaded holes on the vibration table surface. The upper plate 14 is located at the center of the base plate 12 and has T-shaped grooves 13, including vertical and horizontal grooves that can be continuous or partially continuous. The illustration shows a continuous groove. The horizontal groove is perpendicular to the vertical groove, and a concave arc-shaped groove is designed at a certain distance from the end of the horizontal groove. On one side of the fixture body 1 in the same direction as the vertical groove, six mounting holes 11 are evenly distributed in two rows and three columns at equal intervals, each containing a steel wire thread sleeve, extending through to the space where the vertical groove is located and extending to a certain depth on the other side of the vertical groove of the fixture body 1.

[0042] The clamping plate 2 consists of a horizontal clamping plate 24, a vertical clamping plate 21, a columnar clamping plate 25, a mounting groove 26, and a mounting ring 23. The horizontal clamping plate 24 and the vertical clamping plate 21 are perpendicular to each other. On the vertical clamping plate 21, there are two rows of six circular pre-drilled holes 22 that are evenly distributed in three columns with equal spacing. These holes penetrate the vertical clamping plate and are fitted with steel wire thread sleeves. These six holes are the same size as the six holes on the side of the clamping body 1, and the distance between each hole is the same. The mounting groove 26 is located in the center of the horizontal clamping plate 24, extends into the horizontal clamping plate 24 at a certain distance, and is reserved at a certain height from the bottom of the horizontal clamping plate 24. At the same time, the mounting groove 26 also penetrates the upper part of the columnar clamping plate 25. The mounting ring 23 is located on either side of the horizontal clamping plate 24 and is in the shape of a "U". From the other side of the mounting ring 23 as the viewing angle, the clamping plate and the T-shaped groove 13 of the clamping body 1 have the same edge line.

[0043] When the clamping plate 2 is installed in the clamping body 1, the horizontal clamping plate 24 is installed in the horizontal groove, the vertical clamping plate is installed in the vertical groove, and the columnar clamping plate 25 is installed in the concave arc groove, and all three are in close contact with each other; the function of the mounting ring 23 is to facilitate the feeding of the clamping plate into and out of the T-shaped groove 13.

[0044] Viewed from above, the mounting groove 26 on the card and the card plate have the same edge line, and the card has a certain thickness. The card is installed in the gap between the standard part and the fixture 1. If the thickness of the standard part is equal to the depth of the mounting groove 26, the card is not needed; if the thickness of the standard part is less than the depth of the mounting groove 26, the card is needed to fill it to ensure that the test piece and the card together in the mounting groove 26 are still in close contact with the fixture 1.

[0045] The present invention also provides a method for installing a standard test specimen vibration fatigue test fixture, comprising the following steps:

[0046] First, install one end of the standard part into the mounting slot 26 of the clamping plate. If necessary, select whether to install the card. Then, push the clamping plate containing the standard part into the T-shaped groove 13 of the clamping body 1 through the mounting ring 23. Connect the mounting hole 11 on the clamping body 1 to the reserved hole 22 on the clamping plate 2 with bolts. Finally, connect the clamping body 1 to the vibration table surface. Determine the measuring points and control points for the vibration fatigue test, and connect the vibration control and data acquisition equipment. Start the vibration table to conduct the vibration fatigue test on the standard part.

[0047] Beneficial effects:

[0048] The vibration fatigue testing fixture for standard parts described in this invention features a mounting groove 26 on the clamping plate, which allows the clamping end of the test piece to fit tightly with the inner surface of the mounting groove 26. Furthermore, a T-shaped groove 13 is designed inside the fixture body 1, ensuring a tight fit between the clamping plate and the fixture body 1. This achieves the fixation of the fixture body 1, effectively preventing localized stress concentration in the test piece due to external clamping forces, avoiding fatigue damage and fatigue cracks at the clamping end, and ensuring the reliability and stability of the vibration fatigue testing process, as well as the validity and accuracy of the test results.

[0049] In addition, mounting holes 11 are designed on the fixture body 1, and reserved holes 22 are designed on the clamping plate. The clamping plate is connected by bolts, which restricts the degree of freedom of the clamping plate in the T-slot 13 in the direction perpendicular to the transverse slot. This will not cause adverse effects such as stress concentration on the test piece, while ensuring vibration transmission. The fixture has good stability.

[0050] Meanwhile, a columnar clamping plate 25 is set on the clamping plate, which is in close contact with the concave arc groove of the fixture body 1, restricting the degree of freedom of the clamping plate and the transverse groove in the same direction. Compared with the traditional pressure plate bolt connection and the bolt connection with holes, it will not bring stress concentration and prestress to the standard parts, ensuring the effectiveness of fatigue test, while ensuring rigid connection and transmission rate, and further improving the stability of the fixture.

[0051] Furthermore, a card is designed between the standard part clamping end and the transverse groove. When the depth of the mounting groove 26 is much greater than the thickness of the standard part, it can fill the gap and ensure that the surface between the standard part and the fixture body 1 is in close contact. At the same time, for vibration fatigue testing, it is necessary to repeat the vibration fatigue test multiple times in order to obtain the SN curve. It cannot be guaranteed that every standard part and the card groove will be in complete close contact. The card can be used to fill the gap of standard parts of different thicknesses, thus expanding the application range of the vibration fatigue test fixture and making it more versatile.

[0052] Meanwhile, the present invention also provides a method for installing a vibration fatigue test fixture for standard test specimens. The test fixture is simple, the components are easy to disassemble and assemble, the vibration transmission characteristics are good, the efficiency of vibration fatigue testing is improved, and the authenticity and validity of vibration fatigue test results are guaranteed.

[0053] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A standard test piece vibration fatigue test fixture, characterized in that, include: The clamping body (1) and the card plate (2) are inserted into the clamping body (1); The card plate (2) includes: a horizontal card plate (24), a vertical card plate (21), a columnar card plate (25), and a mounting groove (26); The longitudinal plate (21) is vertically connected to one long side of the transverse plate (24) to form a T-shape. The upper and lower surfaces of the transverse plate (24) protrude to form a columnar plate (25). The mounting groove (26) is located on the upper surface of the transverse plate (24) and extends from the side where the longitudinal plate (21) is located to the opposite side. The longitudinal plate (21) has a reserved hole (22). The clamp body (1) has a T-slot, the shape of which is the same as the projection of the card plate (2) along the insertion direction of the card plate (2). The clamp body (1) has a mounting hole (11) that is compatible with the reserved hole (22). When the card plate (2) is inserted into the clamp body (1) along the T-slot, the mounting hole (11) on the clamp body (1) is connected to the reserved hole (22) on the card plate (2) by bolts; The clamping body (1) includes a base plate (12) and an upper plate (14). A T-slot is located on the upper plate (14). The area of ​​the base plate (12) is larger than that of the upper plate (14). The upper plate (14) is mounted on the base plate (12). The base plate (12) has a through hole for fixed installation. The T-slot includes a longitudinal slot adapted to the longitudinal clamping plate (21) and a transverse slot adapted to the transverse clamping plate (24), the transverse slot penetrating the side of the clamping body (1) to expose the standard part to be tested.

2. The standard test specimen vibration fatigue test fixture as described in claim 1, characterized in that, The card plate (2) has a mounting ring (23) on one side.

3. The standard test specimen vibration fatigue test fixture as described in claim 1, characterized in that, The shape of the mounting slot (26) is adapted to the standard part to be tested.

4. The standard test specimen vibration fatigue test fixture as described in claim 1, characterized in that, It also includes a card (3) for filling the gap between the standard part to be tested and the mounting slot (26).

5. The standard test specimen vibration fatigue test fixture as described in claim 1, characterized in that, The T-slot is either through or partially through the insertion direction of the card plate (2).

6. A method for installing a standard test specimen vibration fatigue test fixture, using the standard test specimen vibration fatigue test fixture as described in any one of claims 1-5, comprising the following steps: Install one end of the standard part into the mounting slot (26) of the card plate (2); When the height of the standard part is less than the height of the mounting slot (26), the mounting card (3) is installed; Insert the clamp plate (2) containing the standard parts into the T-slot (13) of the clamp body (1) through the mounting ring (23), and connect the mounting hole (11) on the clamp body (1) with the reserved hole (22) on the clamp plate 2 by bolts; Connect the clamp body (1) to the vibration table through the bottom through hole to complete the installation of the standard parts; Determine the measurement and control points for the vibration fatigue test, connect the vibration control and data acquisition equipment, start the vibration table, and conduct the vibration fatigue test on the standard parts.

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