CN204389291U - Tension and compression cyclic test spring retainer formula sample fixing device - Google Patents

Abstract

Tension and compression cyclic test spring retainer formula sample fixing device, be made up of down clamp and upper position fixture, down clamp comprises the lower sub be connected with testing machine bottom-loaded seat, the lower endcaps of fixing sample, the lower chain connecting lower sub and lower endcaps, the first center position-limit mechanism, the second center position-limit mechanism and the first hydraulic mechanism; Upper position fixture comprises the top connection be connected with testing machine top-loaded seat, the upper end cap of fixing sample, the upper chain connecting top connection and upper end cap, the 3rd center position-limit mechanism, the 4th center position-limit mechanism and the second hydraulic mechanism; Each center position-limit mechanism is by spring retainer assembly, support member and card extender composition, and spring retainer assembly comprises annular bearing, three screw rods, three with external thread and the swivel nut of internal thread, three limit spring and three limit bodies; The annular oil cylinder that first hydraulic mechanism, the second hydraulic mechanism include toroidal piston and combine with toroidal piston.

Description

Spring-limited sample fixing device for tension-compression cycle test

technical field

The utility model belongs to a device for performing mechanical performance tests on brittle materials, in particular to a rock sample fixing device matched with a testing machine in direct tension and compression cycle tests.

Background technique

Alternating tensile and compressive cyclic load tests on rock samples are an important means to understand the ability of rocks to withstand cyclic tensile and compressive loads. Unidirectional tensile test.

In the unidirectional tensile test, the sample fixing device matched with the testing machine is generally composed of an upper clamp and a lower clamp. The chain of the end cap; the lower fixture is required to bear part of the sample and the lower end cap destroyed by the tensile test, and also includes a support member composed of a rigid cylinder and a backing plate. The sample fixing device with this structure cannot perform the mechanical effect test after the peak stress because the supporting member cannot effectively support the sample and the lower end cap during the whole test process. CN200610022224.8 discloses a spring-supported lower clamp for direct tension testing, in which the supporting member of the lower clamp in the sample fixing device is designed as a compression coil spring or a combination of a compression coil spring and a supporting plate. In this way, although the mechanical effect after the peak stress of the rock brittle material test has been directly tested, there are still the following deficiencies: (1) the centerline of the compression coil spring in the test is easy to misalign with the centerline of the testing machine, which will affect the tested material. The specimen forms an additional eccentric force, which affects the accuracy of the test results; (2) Due to the different structures of the upper fixture and the lower fixture, the loading stiffness at both ends of the specimen in the test is inconsistent, resulting in the sudden destruction of the rock under test, which is difficult for the effective determination of the peak stress. (3) When the chain is connected to the end cap, the operation is extremely inconvenient and labor-intensive, and for rocks with low tensile bearing capacity, it is very easy to cause damage to the specimen and cause the test to fail.

In the unidirectional compression test, the specimen is directly placed between the upper and lower bearing plates of the testing machine. The specimen can only bear the compressive load, and the direct tensile load cannot be applied to the specimen, so the alternating compression and tension cannot be performed. Cyclic load test.

Utility model content

The purpose of the utility model is to overcome the deficiencies of the prior art, and provide a spring-limited sample fixing device for tension and compression cyclic tests, so as to realize the alternate test of tension and compression cyclic loads of rock samples, and ensure that the rock samples are fixed during the test. The center line of the device coincides with the center line of the testing machine and the loading stiffness at both ends of the specimen is consistent, which makes the connection between the chain and the end cap convenient and labor-saving, and improves the efficiency.

The spring-limited sample fixing device for tension-compression cycle test of the utility model is composed of a lower clamp and an upper clamp; The lower joint and the lower chain of the lower end cap, the first center limit mechanism, the second center limit mechanism and the first hydraulic mechanism, the lower end cap is composed of a sample fixing groove and a connecting section; The upper joint connected to the base, the upper end cap for fixing the sample, the upper chain connecting the upper joint and the upper end cap, the third center limit mechanism, the fourth center limit mechanism and the second hydraulic mechanism, the upper end cap is composed of the sample fixing groove and Connecting sections; the first center limit mechanism, the second center limit mechanism, the third center limit mechanism and the fourth center limit mechanism have the same structure, all of which are composed of a spring limit assembly, a support member and an adapter plate Composition; the spring limit assembly includes an annular support, three screw rods, three screw sleeves with external threads and internal threads, three limit springs and three limit bodies, the annular support There are three screw holes on the wall, the centerlines of the three screw holes pass through the center of the circular support, and the angle between the centerlines of adjacent screw holes is 120°, the internal threads of the three screw holes are in line with the The external thread of the screw sleeve is matched, the internal thread of the screw sleeve is matched with the external thread of the screw rod, and the limiter is provided with a screw hole, and the internal thread of the screw hole is matched with the external thread of the screw rod; One end of the piece is connected with the adapter plate, and the other end is connected with the ring-shaped support in the spring limit assembly. The three screw sleeves are respectively installed in the three screw holes of the ring-shaped support, and the three screws are connected with the three Screw sleeve combination, three limiters are respectively installed on three screws, three limit springs are respectively set on three screws, and one end is in contact with the limiter installed on the screw, and the other end is in contact with the inner wall of the circular support contact; the structure of the first hydraulic mechanism and the second hydraulic mechanism is the same, both including a circular piston and a circular oil cylinder combined with the circular piston; the first center limit mechanism is combined with the loading seat at the bottom of the testing machine , the ring-shaped support of the spring limit assembly in the first center limit mechanism is in contact with the loading seat at the bottom of the testing machine, the lower joint is located in the center hole of the ring-shaped support, and in the first center limit mechanism One end of the three screw rods of the spring limit assembly is respectively in contact with the outer surface of the lower joint; the second center limit mechanism is installed in combination with the lower end cap, and the ring-shaped support of the spring limit assembly in the second center limit mechanism is connected to the lower end cap. The bottom of the sample fixing groove is in contact with the outer wall, and the connecting section of the lower end cap is located in the central hole of the circular support. contact; the first hydraulic mechanism is located between the first center limit mechanism and the second center limit mechanism, the circular oil cylinder of the first hydraulic mechanism is connected with the adapter plate in the first center limit mechanism, and the first The annular piston of the hydraulic mechanism is connected with the adapter plate in the second center limit mechanism, or the annular oil cylinder of the first hydraulic mechanism is connected with the adapter plate in the second center limit mechanism, and the first hydraulic mechanism The annular piston is connected with the adapter plate in the first central limit mechanism. connected; the lower chain is located in the space surrounded by the first center limit mechanism, the first hydraulic mechanism and the second center limit mechanism; the third center limit mechanism is installed in combination with the upper end cap, and the third center limit mechanism The ring-shaped support of the spring limit assembly is in contact with the bottom outer wall of the sample fixing groove of the upper end cap, the connecting section of the upper end cap is located in the center hole of the ring-shaped support, and the spring limit in the third center limit mechanism One end of the three screw rods of the component is in contact with the outer surface of the connecting section of the upper end cap respectively; the fourth central limit mechanism is installed in combination with the loading seat on the top of the testing machine, and the ring-shaped support of the spring limit component in the fourth central limit mechanism is in contact with the test machine. The top of the machine is in contact with the loading seat, the upper joint is located in the center hole of the circular support, and one end of the three screw rods of the spring limit assembly in the fourth center limit mechanism is respectively in contact with the outer surface of the upper joint; the second The second hydraulic mechanism is located between the third center limit mechanism and the fourth center limit mechanism. The circular oil cylinder of the second hydraulic mechanism is connected with the adapter plate in the third center limit mechanism, and the ring of the second hydraulic mechanism The shaped piston is connected with the adapter plate in the fourth center limit mechanism, or the annular oil cylinder of the second hydraulic mechanism is connected with the adapter plate in the fourth center limit mechanism, and the annular piston of the second hydraulic mechanism is connected with the adapter plate in the fourth center limit mechanism. The adapter plate in the third center limit mechanism is connected; the upper chain is located in the space surrounded by the third center limit mechanism, the second hydraulic mechanism and the fourth center limit mechanism.

In the tension-compression cycle test spring limit type sample fixing device of the utility model, the first center limit mechanism, the second center limit mechanism, the third center limit mechanism and the fourth center limit mechanism The support members are four round rods, the adapter plate is a ring-shaped plate, and the four round rods are evenly installed on the ring-shaped support and the ring surface of the adapter plate; or the first center limit mechanism, the second The supports in the second center limit mechanism, the third center limit mechanism and the fourth center limit mechanism are two plates with circular arc cross sections, and the adapter plate is a circular plate, and the two plates are symmetrical It is installed on the ring surface of the ring support and the adapter plate.

The utility model has the following beneficial effects:

1. The rock sample fixing device described in this utility model cancels the compression coil spring, and sets up a hydraulic mechanism. Since the pressure and stiffness provided by the hydraulic mechanism are much higher than that of the coil spring, it can realize the alternate test of rock tension and compression cycle load , to overcome the shortcomings of only one-way compression or tension test in the current rock test, and perfect the combined test method of rock direct tension and compression load cycle alternating in one-way loading.

2. Since the lower clamp and the upper clamp of the rock sample fixing device described in the utility model are equipped with two center limit mechanisms and a hydraulic mechanism, it can not only ensure that the loading rigidity at both ends of the test piece is consistent, but also more effective. The mechanical effect after the peak stress of the test rock test, and the spring limit assembly in the center limit mechanism of the lower fixture and the upper fixture can ensure that the centerline of the rock sample fixing device in the test coincides with the centerline of the testing machine to avoid It prevents the generation of additional eccentric force, which is beneficial to improve the accuracy of test results.

3. Since the supports in the first center limit mechanism, the second center limit mechanism, the third center limit mechanism and the fourth center limit mechanism are four round rods or two plates with arc-shaped cross sections Therefore, when the chain is connected with the end cap, it is easy to insert the connector pin, and the installation and disassembly operations are simple and convenient. At the same time, it is beneficial to protect the integrity of the rock with low tensile strength before the test, and improves the test success rate.

Description of drawings

Fig. 1 is a structural schematic diagram of a spring-limited sample fixing device for a tension-compression cycle test according to the utility model.

Fig. 2 is the first center limit mechanism or the second center limit mechanism or the third center limit mechanism or the fourth center limit mechanism in the tension-compression cycle test spring limit type sample fixing device of the utility model. A schematic diagram of the structure (the support is a round rod), the center limiting mechanism is in a non-working state.

FIG. 3 is a top view of FIG. 2 .

Fig. 4 is the first center limit mechanism or the second center limit mechanism or the third center limit mechanism or the fourth center limit mechanism in the tension-compression cycle test spring limit type sample fixing device of the utility model. Schematic diagrams of the two structures (the support is an arc-shaped plate body), the center limiting mechanism is in working condition.

FIG. 5 is a top view of FIG. 4 .

Fig. 6 is a schematic structural diagram of the first hydraulic mechanism or the first hydraulic mechanism in the spring-limited sample fixing device for the tension-compression cycle test of the present invention.

FIG. 7 is a top view of FIG. 6 .

In the figure, 1—loading seat at the bottom of the testing machine, 2—spring limit assembly, 2-1—circular support, 2-2—screw rod, 2-3—screw sleeve, 2-4—limit spring, 2 -5—limiting body, 3—lower joint, 4—support, 5—adapter plate, 6—lower chain, 7—lower pin, 8—lower end cap, 9—rock sample, 10—upper end cap, 11 —upper pin, 12—upper chain, 13—upper joint, 14—top loading seat of testing machine, 15—circular piston, 16—circular oil cylinder, 17—piston limit ring, 18—sealing ring, 19— Oil delivery pipe, 20—control valve, 21—pressure gauge.

Detailed ways

The following examples will further illustrate the spring-limited sample fixing device for the tension-compression cycle test of the present utility model.

In this embodiment, the spring-limited sample fixing device for the tension-compression cycle test is shown in Figure 1, which consists of a lower clamp and an upper clamp. The lower fixture includes a lower joint 3 connected to the loading seat 1 at the bottom of the testing machine, a lower end cap 8 for fixing the sample, a lower chain 6 connecting the lower joint and the lower end cap, a first center limit mechanism, and a second center limit mechanism And the first hydraulic mechanism, the lower end cap 8 is composed of a sample fixing groove and a connecting section; the upper clamp includes an upper joint 13 connected to the top loading seat 14 of the testing machine, an upper end cap 10 for fixing the sample, connecting the upper joint and the upper end The upper chain 12 of the cap, the third center limit mechanism, the fourth center limit mechanism and the second hydraulic mechanism, the upper end cap 10 is composed of a sample fixing groove and a connecting section.

The structures of the first center limit mechanism, the second center limit mechanism, the third center limit mechanism and the fourth center limit mechanism are the same, and are all composed of a spring limit assembly 2, a support member 4 and an adapter plate 5 , as shown in Figure 2 and Figure 3; the spring limit assembly 2 includes an annular support 2-1, three screw rods 2-2, three screw sleeves 2-3 with external threads and internal threads, three limit Spring 2-4 and three stoppers 2-5, three screw holes are arranged on the wall of described annular support, and the center line of three screw holes all passes through the center of annular support, and adjacent The angle between the centerlines of the screw holes is 120°, and the internal threads of the three screw holes match the external threads of the screw sleeve 2-3, and the internal threads of the screw sleeve 2-3 are matched with the screw rod 2-2. The outer thread of the screw rod 2-2 is matched with the outer thread, the limiter 2-5 is a nut that matches the outer thread of the screw rod 2-2, the limiter spring 2-4 is a cylindrical compression coil spring; the support member 4 is four round Rod, the adapter plate 5 is a ring-shaped plate, its outer diameter and inner hole diameter are the same as the ring-shaped support 2-1, and four round rods are evenly installed on the ring-shaped support 2-1 and the adapter plate 5 On the annular surface of the ring, one end of them is connected with the adapter plate 5, and the other end is connected with the annular support 2-1 in the spring limit assembly; the three screw sleeves 2-3 are respectively installed on the annular support In the three screw holes, the three screw rods 2-2 are respectively combined with the three screw sleeves, the three limiting bodies 2-5 are respectively installed on the three screw rods, and the three limiting springs 2-4 are respectively set on the three screw rods, and One end is in contact with the limiting body 2-5 installed on the screw rod, and the other end is in contact with the inner wall of the annular support 2-1.

The structures of the first hydraulic mechanism and the second hydraulic mechanism are shown in Fig. 6 and Fig. 7, both comprising an annular piston 15, an annular oil cylinder 16, a piston stop ring 17 and a sealing ring 18, and an annular piston One end of 15 is inserted in the annular chamber of annular oil cylinder 16, and the closed end of annular chamber of annular oil cylinder 16 is equipped with the oil delivery pipe 19 that communicates with this cavity, and described oil delivery pipe 19 is provided with control Valve 20 and pressure gauge 21, piston limit ring 17 are installed on the opening end of the annular cavity of annular oil cylinder 16, and sealing ring 18 is respectively installed on the end of annular piston 15 inserting one end of annular cavity and On the piston limit ring 17.

The combination of components or components of the lower fixture: the first central limit mechanism is installed in combination with the bottom loading seat 1 of the testing machine, and the ring-shaped support of the spring limit assembly in the first central limit mechanism is connected with the bottom loading seat 1 of the testing machine Contact, the lower joint 3 is located in the center hole of the circular support, and one end of the three screw rods of the spring limit assembly in the first center limit mechanism is respectively in contact with the outer surface of the lower joint 3; the second center limit The mechanism is installed in combination with the lower end cap 8, and the circular support of the spring limit assembly in the second central limit mechanism is in contact with the bottom outer wall of the sample fixing groove of the lower end cap 8, and the connecting section of the lower end cap 8 is located in the circular ring. In the center hole of the support, one end of the three screw rods of the spring limit assembly in the second center limit mechanism is respectively in contact with the outer surface of the connecting section of the lower end cap; the first hydraulic mechanism is located at the first center limit mechanism and the second center limit mechanism. Between the mechanisms, the annular oil cylinder 16 of the first hydraulic mechanism is connected with the adapter plate 5 in the first central limit mechanism, and the circular piston 15 of the first hydraulic mechanism is connected with the transfer plate in the second central limit mechanism. The plate 5 is connected; the lower end of the lower chain 6 is connected with the lower joint 3 installed on the loading seat 1 at the bottom of the testing machine, and the upper end forms a detachable connection with the connecting section of the lower end cap through the lower pin 7, and the lower chain 6 is located in the first center limit mechanism , In the space surrounded by the first hydraulic mechanism and the second center limit mechanism.

Combination of components or components of the upper fixture: the third center limit mechanism and the upper end cap 10 are installed in combination, the ring-shaped support of the spring limit assembly in the third center limit mechanism and the bottom of the sample fixing groove of the upper end cap 10 The outer wall is in contact, the connecting section of the upper end cap 10 is located in the central hole of the annular support, and one end of the three screw rods of the spring limiter assembly in the third center limit mechanism is in contact with the outer surface of the upper end cap connecting section respectively; the fourth The center limit mechanism is installed in combination with the top loading seat 14 of the testing machine, and the circular support of the spring limit assembly in the fourth center limit mechanism is in contact with the top loading seat 14 of the testing machine, and the upper joint 13 is located on the ring In the center hole of the shaped support, one end of the three screw rods of the spring limit assembly in the fourth center limit mechanism is respectively in contact with the outer surface of the upper joint 13; the second hydraulic mechanism is located at the third center limit mechanism, the fourth center limit mechanism Between the mechanisms, the annular oil cylinder 16 of the second hydraulic mechanism is connected with the adapter plate 5 in the third central limit mechanism, and the circular piston 15 of the second hydraulic mechanism is connected with the transition in the fourth central limit mechanism. Plate 5 is connected; the upper end of the upper chain 12 is connected with the upper joint 13 installed on the top loading seat 14 of the testing machine, and the lower end forms a detachable connection with the upper end cap connection section through the upper bolt 11, and the upper chain 12 is located in the third center limit mechanism , the second hydraulic mechanism, and the space enclosed by the fourth center limit mechanism.

The installation method of the rock sample 9 is shown in Figure 1, and the two ends are bonded to the sample fixing grooves of the upper end cap 10 and the lower end cap 8 by high-strength glue.

It should be noted that the installation method of the screw rod 2-2, the screw sleeve 2-3, the limit spring 2-4, and the limit body 2-5 in the spring limit assembly 2 is: firstly, the three screw sleeves 2-3 are respectively Combine with the three screw rods 2-2, then insert the three screw rods 2-2 into the three screw holes of the annular support 2-1 respectively, and then respectively set the three limit springs 2-4 on the three screw rods located in the annular ring On the section in the center hole of the support, the three limiters 2-5 are respectively installed on the sections of the three screw rods located in the center hole of the circular support, and the three limiters are adjusted by adjusting the three limiters. The position bodies are all located at equidistant ends of the sections of the three screw rods in the ring body, the three limit springs are in the same compressed state, and the three screw rods are fixed on the annular support through three screw sleeves.

The utility model is not limited to the above-mentioned embodiments, for example, the first center limit mechanism, the second center limit mechanism, the third center limit mechanism and the fourth center limit mechanism can also be as shown in Fig. 4 and Fig. 5 The structure, that is, the support member 4 is two boards with a circular arc-shaped cross section, the adapter plate 5 is a ring-shaped plate, and the two boards are symmetrically installed on the ring-shaped support 2-1 and the adapter plate 5 One end of them is connected with the adapter plate 5, and the other end is connected with the annular support 2-1 in the spring limiting assembly.

Claims (3)

1. a tension and compression cyclic test spring retainer formula sample fixing device, be made up of down clamp and upper position fixture, described down clamp comprises the lower sub (3) be connected with testing machine bottom-loaded seat (1), the lower endcaps (8) of fixing sample, connect the lower chain (6) of lower sub and lower endcaps, lower endcaps (8) is made up of sample fixing and linkage section, described upper position fixture comprises the top connection (13) be connected with testing machine top-loaded seat (14), the upper end cap (10) of fixing sample, connect the upper chain (12) of top connection and upper end cap, upper end cap (10) is made up of sample fixing and linkage section, it is characterized in that down clamp also comprises the first center position-limit mechanism, second center position-limit mechanism, first hydraulic mechanism, upper position fixture also comprises the 3rd center position-limit mechanism, 4th center position-limit mechanism and the second hydraulic mechanism,

The structure of described first center position-limit mechanism, the second center position-limit mechanism, the 3rd center position-limit mechanism, the 4th center position-limit mechanism is identical, forms by spring retainer assembly (2), support member (4) and card extender (5), described spring retainer assembly (2) comprises annular bearing (2-1), three screw rods (2-2), three swivel nuts (2-3) with external thread and internal thread, three limit spring (2-4) and three limit bodies (2-5), the wall of described annular bearing is provided with three screws, the center line of three screws is all by the center of annular bearing, and the angle between the center line of adjacent screw is 120 °, the external thread of the internal thread of three screws and swivel nut (2-3) matches, the internal thread of described swivel nut (2-3) and the external thread of described screw rod (2-2) match, described limit body (2-5) is provided with screw, the external thread of the internal thread of this screw and screw rod (2-2) matches, one end of support member (4) is connected with card extender (5), the other end is connected with the annular bearing (2-1) in spring retainer assembly, three swivel nuts (2-3) are arranged in three screws of annular bearing respectively, three screw rods (2-2) are combined with three swivel nuts respectively, three limit bodies (2-5) are arranged on three screw rods respectively, three limit spring (2-4) are set on three screw rods, and one end contacts with the limit body be arranged on screw rod, the contact internal walls of the other end and annular bearing (2-1),

The structure of described first hydraulic mechanism, the second hydraulic mechanism is identical, the annular oil cylinder (16) including toroidal piston (15) and combine with toroidal piston;

First center position-limit mechanism and testing machine bottom-loaded seat (1) combine to be installed, in first center position-limit mechanism, the annular bearing of spring limit assembly contacts with testing machine bottom-loaded seat (1), described lower sub (3) is positioned at the center pit of described annular bearing, and in the first center position-limit mechanism, three screw rod one end of spring limit assembly contact with the lateral surface of lower sub (3) respectively; Second center position-limit mechanism and lower endcaps (8) combine installs, in second center position-limit mechanism, the annular bearing of spring limit assembly contacts with the sample fixing bottom outer wall of lower endcaps (8), the linkage section of lower endcaps (8) is positioned at the center pit of described annular bearing, and in the second center position-limit mechanism, three screw rod one end of spring limit assembly contact with the lateral surface of lower endcaps linkage section respectively; Described first hydraulic mechanism is between the first center position-limit mechanism, the second center position-limit mechanism, the annular oil cylinder (16) of the first hydraulic mechanism is connected with the card extender in the first center position-limit mechanism, the toroidal piston (15) of the first hydraulic mechanism is connected with the card extender in the second center position-limit mechanism, or the annular oil cylinder (16) of the first hydraulic mechanism is connected with the card extender in the second center position-limit mechanism, the toroidal piston (15) of the first hydraulic mechanism is connected with the card extender in the first center position-limit mechanism; The space that described lower chain (6) is positioned at the first center position-limit mechanism, the first hydraulic mechanism, the second center position-limit mechanism surround;

3rd center position-limit mechanism and upper end cap (10) combine installs, in 3rd center position-limit mechanism, the annular bearing of spring limit assembly contacts with the sample fixing bottom outer wall of upper end cap (10), the linkage section of upper end cap (10) is positioned at the center pit of described annular bearing, and in the 3rd center position-limit mechanism, three screw rod one end of spring limit assembly contact with the lateral surface of upper end cap linkage section respectively; 4th center position-limit mechanism and testing machine top-loaded seat (14) combine to be installed, in 4th center position-limit mechanism, the annular bearing of spring limit assembly contacts with testing machine top-loaded seat (14), described top connection (13) is positioned at the center pit of described annular bearing, and in the 4th center position-limit mechanism, three screw rod one end of spring limit assembly contact with the lateral surface of top connection (13) respectively;

Described second hydraulic mechanism is between the 3rd center position-limit mechanism, the 4th center position-limit mechanism, the annular oil cylinder (16) of the second hydraulic mechanism is connected with the card extender in the 3rd center position-limit mechanism, the toroidal piston (15) of the second hydraulic mechanism is connected with the card extender in the 4th center position-limit mechanism, or the annular oil cylinder (16) of the second hydraulic mechanism is connected with the card extender in the 4th center position-limit mechanism, the toroidal piston (15) of the second hydraulic mechanism is connected with the card extender in the 3rd center position-limit mechanism; The space that described upper chain (12) is positioned at the 3rd center position-limit mechanism, the second hydraulic mechanism, the second volute spring (16), the 4th center position-limit mechanism surround.

2. tension and compression cyclic test spring retainer formula sample fixing device according to claim 1, it is characterized in that the support member (4) in the first center position-limit mechanism, the second center position-limit mechanism, the 3rd center position-limit mechanism and the 4th center position-limit mechanism is four round bars, card extender (5) is annular plate, and four round bars are evenly arranged on the anchor ring of annular bearing (2-1) and card extender (5).

3. tension and compression cyclic test spring retainer formula sample fixing device according to claim 1, the support member (4) that it is characterized in that in the first center position-limit mechanism, the second center position-limit mechanism, the 3rd center position-limit mechanism and the 4th center position-limit mechanism is two xsects is the plate body of circular arc, card extender (5) is annular plate, and two plate body symmetries are arranged on the anchor ring of annular bearing (2-1) and card extender (5).