A high temperature test clamping device capable of applying variable load

Abstract

A high-temperature test clamping device capable of applying variable loads comprises a fixed end provided with a large flange for connecting to a high-temperature test chamber and a fixed frame fixed to the large flange; an operating end comprising a rotating bolt and a connecting rod for connecting the rotating bolt to the fixed frame; a monitoring transmission system comprising a limit cylinder, a transmission shaft, a rotating motor, and a sensor; the limit cylinder being movably inserted into a through hole of a small flange via a support rod at the bottom; the upper section of the through hole in the center of the limit cylinder being threadedly connected to the rotating bolt; one end of the transmission shaft being transmission-connected to the rotating motor and the other end being connected to the rotating bolt to transmit torque, and the transmission shaft and the rotating bolt being capable of relative axial movement; the upper and lower ends of the sensor being connected to the rotating motor and the clamping end, respectively; the clamping end being used to clamp the sample. This device can achieve locking and clamping of the sample and the application of variable loads, facilitating the study of creep and microparticle erosion characteristics of nickel-based single crystal high-temperature alloy materials under high-temperature loading.

Description

Technical Field

[0001] The invention belongs to the field of high temperature testing, and in particular relates to a high temperature testing clamping device capable of applying a variable load. Background Art

[0002] Turbine blades are one of the core hot-end components of aircraft engines, and their safe service is crucial to the normal operation of aircraft engines. The service environment of turbine blades is extremely complex and harsh. During service, they are subjected to a variety of variable loads such as centrifugal loads, aerodynamic loads, and vibration loads. At the same time, they are subjected to the erosion and corrosion of high-temperature combustion gases. Creep failure and fatigue failure caused by centrifugal force are the main causes of blade damage. Nickel-based single-crystal high-temperature alloys have superior high-temperature strength, good oxidation resistance, thermal corrosion resistance, cold and thermal fatigue resistance, as well as good plasticity and weldability. They can work at high temperatures for a long time and have become an important material for manufacturing hot-end components of aircraft engines. As an important material for aircraft engine turbine blades, the mechanical properties of nickel-based single-crystal high-temperature alloys have a significant impact on aircraft engines.

[0003] In the high-temperature tests currently being conducted at home and abroad, nickel-based single-crystal high-temperature alloy specimens are often used to study the high-temperature performance of turbine blades. However, applying variable loads to the nickel-based single-crystal high-temperature alloy specimens during the test is a key point. At the same time, continuously and effectively clamping and fixing specimens with different ends during high-temperature tests is also a technical difficulty. Currently, there is a lack of such a clamping device that can be assembled in a high-temperature test system to achieve automatic locking of nickel-based single-crystal high-temperature alloy specimens to apply variable loads. Therefore, in high-temperature test research work, it is necessary to design a specimen fixture that can be assembled in a high-temperature test and can apply variable loads. Summary of the Invention

[0004] The purpose of the present invention is to provide a high-temperature test clamping device capable of applying variable loads, so as to facilitate the study of creep and microparticle erosion characteristics of nickel-based single crystal high-temperature alloy materials under high-temperature loading conditions.

[0005] In order to achieve the above-mentioned object, the technical solution adopted by the present invention is: a high-temperature test clamping device capable of applying a variable load, comprising a fixed end, the fixed end being provided with a large flange for connecting to a high-temperature test chamber and a fixing frame fixed to the large flange;

[0006] The operating end includes a rotating bolt and a connecting rod for connecting the rotating bolt to the fixed frame, and the rotating bolt and the connecting rod are connected to each other in a relatively rotating manner;

[0007] The monitoring transmission system includes a limit cylinder, a transmission shaft, a rotating motor and a sensor. The limit cylinder is movably inserted into the through hole of the small flange through a support rod at the bottom. The upper section of the through hole in the center of the limit cylinder is threadedly connected to the rotating bolt. One end of the transmission shaft is connected to the rotating motor, and the other end is connected to the rotating bolt to transmit torque. The transmission shaft and the rotating bolt can move relative to each other in the axial direction. The upper and lower ends of the sensor are respectively connected to the rotating motor and the clamping end through connecting pieces. The small flange is fixed to the large flange.

[0008] The clamping end passes through the small flange and the large flange and is used to clamp the sample. The clamping end includes fixed teeth, movable teeth, an adjustment component, a fixed tooth chuck arranged on the fixed teeth, and a movable tooth chuck arranged on the movable teeth. The adjustment component is used to control the linear movement of the movable teeth relative to the fixed teeth.

[0009] The connecting rod is a fine-tuning rotary connecting rod with an external thread. The fine-tuning rotary connecting rod is threadedly connected to the crossbeam of the fixed frame. The pitch of the fine-tuning rotary connecting rod is smaller than the pitch of the rotating bolt.

[0010] A ball head is provided at the end of the fine-tuning rotary connecting rod, and a ball socket matched with the ball head is provided at the top of the rotating bolt.

[0011] The end of the transmission shaft is provided with a transmission head, which is inserted into the transmission groove on the end face of the rotating bolt, and the transmission head and the transmission groove are engaged for transmission.

[0012] The transmission shaft is a cross transmission shaft, and the cross section of the transmission head is cross-shaped; the transmission groove of the rotating bolt is a cross-shaped groove.

[0013] A cooling and temperature control system is provided between the sensor and the clamping end, and the cooling and temperature control system is connected to the clamping end through a rod.

[0014] The adjustment assembly includes a worm gear and a spiral telescopic shaft. The worm gear is fixed on the spiral telescopic shaft and is located in an operating hole set in the fixed tooth. The control end of the spiral telescopic shaft extends out of the operating hole. A rack is provided on the movable tooth, and the rack is movably set in the movable hole on the fixed tooth. The movable hole and the operating hole are arranged side by side and connected by a notch, so that the worm gear engages with the rack through the notch.

[0015] The fixed tooth chuck includes two fixed tooth rotating teeth rotatably connected to the bottom of the fixed teeth, and the movable tooth chuck includes two movable tooth rotating teeth rotatably connected to the bottom of the movable teeth. The fixed tooth rotating teeth and the movable tooth rotating teeth have the same structure, both of which are polygonal cylinders with multiple planes on the cylindrical surface, and patterns are provided on the cylindrical surface to increase friction.

[0016] The fixed tooth rotating teeth and the movable tooth rotating teeth are regular hexagonal prisms or regular octagonal prisms.

[0017] The movable tooth is equipped with a rotating shaft extending vertically downward, and the movable tooth rotating tooth is rotatably connected to the rotating shaft, and the rotating shaft and the movable tooth rotating tooth are axially limited; the fixed tooth is provided with a rotating handle for rotating the fixed tooth rotating tooth, and the rotating handle is connected to the fixed tooth rotating tooth through the rotating shaft passing through the fixed tooth.

[0018] The beneficial effects of the present invention are: 1. The test device in the present invention realizes automatic locking, clamping and fixation of nickel-based single crystal high-temperature alloy samples and variable load application of nickel-based single crystal high-temperature alloy samples through five parts: a fixed end, an operating end, a monitoring and transmission system, a cooling and temperature control system and a clamping end.

[0019] 2. The operating end consists of a fine-tuning connecting rod and a rotating bolt. (1) The rotating bolt can quickly apply the load and initially adjust the load to the required range of the test; (2) The fine-tuning connecting rod can further fine-tune the load to ensure the accuracy of the load applied in the test; (3) The two are connected by a spherical slot. The rotation of the two does not affect each other, and the displacement in the vertical direction can be transmitted as much as possible.

[0020] 3. The monitoring transmission system consists of four parts: a limit cylinder, a cross transmission shaft, a rotating motor and a sensor. (1) The limit cylinder can prevent the horizontal rotation of the rotating bolt from being transmitted to other structures, and only transmits the vertical displacement of the rotating bolt. It also plays a role in protecting the sensor, ensuring the rationality of the load applied to the structure of the device of the present invention; (2) The upper end of the cross transmission shaft can realize synchronous rotation by embedding the rotating bolt, and the vertical displacement does not affect each other; (3) The small flange can facilitate the installation and fixation of the device body to the experimental compartment, and also provide better airtightness for the test device to ensure the test conditions; (4) The rotating motor can realize real-time adjustment of the load on the sample through the cross transmission shaft; (5) The sensor can realize the quantification and visualization of the test load value, facilitate the application and recording of the load, and feedback the real-time load data to the rotating motor.

[0021] 4. The clamping end includes five parts: fixed teeth, movable teeth, worm gear, spiral telescopic shaft and rotating teeth. (1) The upper part of the fixed teeth can ensure the airtightness of the test chamber and provide a more accurate environment for the test; (2) The side surfaces of the rotating teeth are patterned and can be sprayed with wear-resistant insulation materials to form a wear-resistant insulation layer, ensuring that the sample is loaded in the clamped state without slipping and ensuring uniform heating of the sample; the rotating teeth are octagonal and can be adjusted to a suitable angle by rotation so that they can match the shape of the sample and better clamp the sample; (3) The spiral telescopic shaft is fixed to the worm gear, and the exposed section can be connected to the motor so that it can lock the sample in real time outside the test chamber to prevent slipping due to high temperature softening; (4) The spiral telescopic shaft is used in conjunction with the outer retaining groove of the fixed teeth to ensure that the sample is installed and fixed and automatically locked in real time, so as to be suitable for a wider range of test environments. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a schematic diagram of the structure of the present invention;

[0023] Figure 2 It is a structural diagram of the fixed end and the operating end;

[0024] Figure 3 Schematic diagram of the structure of the monitoring transmission system and cooling temperature control system;

[0025] Figure 4 This is a schematic diagram of the structure of the monitoring transmission system;

[0026] Figure 5 Schematic diagram of the clamping end structure;

[0027] Figure 6 Schematic diagram of the cross-sectional structure of the clamping end;

[0028] Figure 7 This is a schematic diagram of the state where the clamping end clamps the test piece 1;

[0029] Figure 8 This is a schematic diagram of the state where the clamping end clamps the test piece 2;

[0030] Figure 9 This is a schematic diagram of the state where the clamping end clamps the test piece 3;

[0031] Figure 10 This is a schematic diagram of the installation of the present invention and the high temperature test chamber;

[0032] Markings in the figure: A. device of the present invention, B. high-temperature test chamber, 1. fine-tuning connecting rod, 2. fixing frame, 3. rotating bolt, 4. limiting cylinder, 5. cross transmission shaft, 6. rotating motor, 7. sensor, 8. cooling and temperature control system, 9. fixed gear, 901. operating hole, 902. movable hole, 10. rotating telescopic rod, 11. worm gear, 12. movable gear, 1201, rack, 13. small flange, 14. large flange, 15. movable tooth rotating gear, 16. fixed tooth rotating gear. DETAILED DESCRIPTION

[0033] The present invention will be further described in detail below with reference to the accompanying drawings and examples, but they are not intended to limit the invention in any way.

[0034] The high-temperature test clamping device capable of applying variable loads described in the present invention comprises five parts: a fixed end, an operating end, a monitoring and transmission system, a cooling and temperature control system, and a clamping end.

[0035] like Figure 1 、 2As shown, the fixed end is composed of a fixed frame 2 and a large flange 14. By fixing the two, the entire device can be fixed at a specific vertical height, which is convenient for subsequent device installation. The operating end is composed of a fine-tuning rotary connecting rod 1 and a rotating bolt 3. The fine-tuning rotary connecting rod 1 is threadedly connected to the crossbeam at the top of the fixed frame 2. The upper end of the fine-tuning rotary connecting rod 1 is a turntable handle for realizing its rotation, and the lower end of the fine-tuning rotary connecting rod 1 is provided with a ball head; the upper end of the rotating bolt 3 is provided with a turntable handle, and the center of the turntable handle is provided with a ball socket that can cooperate with the ball head. The ball head of the fine-tuning rotary connecting rod 1 is embedded in the ball socket of the rotating bolt 3 to realize the connection between the two. The lower end face of the rotating bolt 3 is provided with a groove; the pitch of the external thread of the rotating bolt 3 is greater than the pitch of the external thread on the fine-tuning rotary connecting rod 1.

[0036] like Figure 3 、 4 As shown, the monitoring transmission system mainly consists of four parts: a limiting cylinder 4, a cross transmission shaft 5, a rotating motor 6 and a sensor 7. The described limiting cylinder 4 is provided with support rods extending downward on both sides of the cylinder body, and the lower ends of the two support rods are inserted into the through holes of the small flange 13. A through hole is provided in the center of the cylinder body, and the upper section of the through hole is provided with an internal thread that can cooperate with the rotating bolt 3, and the lower section of the through hole is a light hole; one end of the shaft body of the described cross transmission shaft 5 is transmission-connected with the output shaft of the rotating motor 6, and the other end of the shaft body is provided with a transmission disk with a cross-shaped cross section. After the cross transmission shaft 5 and the rotating motor 6 are connected, they are installed in the through hole of the limiting cylinder 4, and the rotating motor 6 is embedded in the light hole part of the through hole with interference fit. The transmission disk of the cross transmission shaft 5 is inserted into the cross-shaped groove at the bottom of the rotating bolt 3 to transmit torque. The cross-shaped groove has a certain depth, so that the rotating bolt 3 and the cross transmission shaft 5 can have relative displacement in the axial direction; the sensor 7 is a tension and pressure sensor, and the upper end of the sensor 7 is connected to the bottom of the rotating motor 6 through a connecting rod, and the lower end of the sensor 7 is connected to the cooling temperature control system 8 through another connecting rod. The connecting rods are all hollow rods, and the necessary wires and communication lines of the rotating motor 6, the sensor 7 and the cooling temperature control system 8 pass through the connecting rods and are connected to the external controller.

[0037] As a variation, the transmission head of the transmission shaft may also adopt a spline, and the corresponding rotating bolt may be provided with a keyway matching therewith, thereby realizing the driving of the rotating bolt by the transmission shaft while taking into account the relative displacement of the transmission shaft and the rotating bolt in the axial direction.

[0038] The cooling temperature control system 8 can be a conventional product and is not an improvement point of the present invention.

[0039] Continue to refer Figure 1-3 The small flange 13 is fixed on the upper surface of the large flange 14, and the two are coaxial. The center of the small flange 13 is provided with a square through hole, and the center of the large flange 14 is provided with a circular through hole.

[0040] like Figure 5 、 6 As shown, the clamping end mainly includes fixed teeth 9, movable teeth 12, worm gear 11, and spiral telescopic shaft 10. The fixed teeth 9 are embedded in the square through-hole of the small flange 13 to ensure the airtightness of the test chamber and provide a more accurate environment for the test. The fixed teeth 9 are provided with an operating hole 901 and a movable hole 902 extending horizontally and opening on the side of the fixed teeth. The operating hole 901 and the movable hole 902 are arranged side by side and connected by a gap. The bottom of the fixed teeth 9 is connected to the fixed tooth chuck; the upper part of the movable teeth 12 is provided with a rack 1201, which is movably arranged in the movable hole 902 of the fixed teeth 9, and the lower part of the movable teeth 12 is connected to the movable tooth chuck. The worm gear 11 is installed in the operating hole 901 and engages with the rack 1201 in the movable hole through the gap to drive the rack 1201 to move linearly. The worm gear 11 is installed on the spiral telescopic shaft 10, and the end of the spiral telescopic shaft 10 extends out of the operating hole to facilitate manual or motor control of its rotation. The driving principle of the worm gear 11 on the rack 1201 in the present invention is the same as that of the adjustable wrench in the prior art. Therefore, after rotating the spiral telescopic shaft 10, the movable tooth chuck can be driven close to or away from the fixed tooth chuck to achieve clamping or loosening of the sample.

[0041] During the test, the clamping end needs to clamp the end of the specimen. Due to the different shapes of the specimen ends, it is difficult for a fixed-shaped chuck to clamp the specimen. To this end, the present invention improves the fixed-tooth chuck to two fixed-tooth rotating teeth 16 that are rotatably connected to the bottom of the fixed teeth 9. The fixed-tooth rotating teeth 16 are regular octagonal prisms with a pattern on the cylindrical surface to increase friction. Similarly, the movable-tooth chuck is improved to two movable-tooth rotating teeth 15 that are rotatably connected to the bottom of the movable teeth 12. The movable-tooth rotating teeth 15 and the fixed-tooth rotating teeth 16 have the same structure, shape, and specifications.

[0042] Furthermore, the movable tooth 12 is equipped with a rotating shaft extending vertically downward, and the movable tooth rotating tooth 15 is rotatably connected to the rotating shaft. A convex and concave structure is used between the rotating shaft and the movable tooth rotating tooth 15 to achieve axial limitation to prevent the movable tooth rotating tooth 15 from falling off; the fixed tooth 9 is also provided with a rotating handle for rotating the fixed tooth rotating tooth 16, and the rotating handle is connected to the fixed tooth rotating tooth 16 through the rotating shaft passing through the fixed tooth.

[0043] Below Figure 7 、 8 , 9 as an example, the clamping method of the rotating teeth of the present invention is described.

[0044] like Figure 7 As shown, when the end of the sample 17 is rectangular, rotate the four rotating teeth so that the clamping surface of the rotating teeth is parallel to the side of the sample end, and then adjust the movable teeth to clamp the sample. At this time, there are two rotating teeth on each side of the sample, which can ensure sufficient clamping force for the test.

[0045] like Figure 8 As shown, when the end of the sample 17 is a square, if the side length is large, you can use Figure 8 However, if the side length is small, it is difficult for the two rotating teeth on the same side to contact the specimen at the same time, and the clamping effect of the four rotating teeth will be difficult to play. Therefore, in this case, you can also rotate these rotating teeth and adjust the angle of the specimen so that the inclined surface on the rotating tooth cylindrical surface can be parallel to the side surface of the specimen end, and then adjust the movable teeth to clamp the specimen. At this time, all four sides of the specimen are in contact with the four rotating teeth, which can ensure sufficient clamping force for the test.

[0046] like Figure 9 As shown, when the end of the sample 17 is cylindrical, you can refer to Figure 9 The clamping method in can also provide sufficient clamping force.

[0047] The present invention can provide static load and variable load to the specimen. (1) Static load application: after the two ends of the specimen are clamped by two sets of devices, the initial loading of the specimen is achieved by rotating the rotating bolt 3. At this time, the rotating bolt 3 is axially limited by the fine-tuning connecting rod 1, so the rotation of the rotating bolt 3 can achieve the axial movement of the limiting cylinder 4. Since the rotating motor 6 is embedded in the limiting cylinder 4, the rotating motor 6 can synchronize the axial movement of the limiting cylinder 4. The rotating motor 6 transmits the tensile force to the clamping end through the connected sensor 7 and the cooling and temperature control system 8, and then acts on the specimen. After the rotating bolt 3 is adjusted into place, it no longer rotates. At this time, a static load is applied to the specimen. This process is manually adjusted; (2) Variable load application: during the static load application process, the rotating motor 6 is started, and the rotating bolt 3 is driven to rotate through the cross transmission shaft 5, thereby driving the axial movement of the limiting cylinder 4. Through force transmission, the load of the specimen changes accordingly, and variable load application is achieved.

[0048] The specific assembly process of the present invention is as follows: first, assemble the fixed end and the operating end, screw the fine-tuning connecting rod 1 and the fixed frame 2 through threads, embed the ball head at the lower end of the fine-tuning connecting rod 1 and the ball socket at the upper end of the rotating bolt 3, and fix the fixed frame 2 to the large flange 14; secondly, assemble the monitoring transmission system, first connect the cross transmission shaft 5 and the rotating motor 6, then embed them into the limiting cylinder 4, and embed the upper end of the cross transmission shaft 5 into the cross-shaped groove at the lower end of the rotating bolt 3, and screw the limiting cylinder 4 and the rotating bolt 3 coaxially through threads, adjust them to the appropriate position, embed the lower end of the limiting cylinder 4 into the small flange 13, and install the sensor. 7 is connected to the lower end of the limit cylinder 4, the large and small flanges are stacked and connected by bolts; then the cooling temperature control system is assembled, the upper end of the cooling temperature control system 8 is connected to the sensor 7 through a rod, and the lower end is connected to the upper end of the fixed tooth 9 of the clamping end through a rod; then the clamping end is assembled, first the fixed tooth rotating tooth 16 and the movable tooth rotating tooth 15 are respectively connected to the fixed tooth 9 and the movable tooth 12 through the rotating shaft, the worm gear 11 is embedded in the operating hole inside the fixed tooth 9, and is fixed to the rotating telescopic rod 10, and then the rack of the movable tooth 12 is installed into the movable hole of the fixed tooth, and the worm gear is adjusted so that it is engaged with the rack of the movable tooth through the operating hole to complete the assembly of the device of the present invention.

[0049] Before the test, two sets of the device A of the present invention are installed at opposite positions of the high temperature test chamber B through the large flange 14 (such as Figure 10 As shown in the figure, both ends of the specimen are clamped by the clamping ends of two sets of devices respectively.

[0050] When the test begins, the high-temperature test chamber B begins to heat up, and the cooling temperature control system 8 is started to cool the upper part of the device A of the present invention. After reaching the specified temperature, the value of the sensor 7 is zeroed. The sample can be initially loaded by rotating the rotating bolt 3, and the sample loading can be further fine-tuned by rotating the fine-tuning connecting rod 1, thereby improving the accuracy of the test load loading, reducing the test error, and realizing the visualization and quantification of real-time loading. According to the test needs, the application of variable load can also be carried out by controlling the rotation of the rotating motor 6. During the test, the meshing force between the rotating teeth and the sample is monitored in real time, and the sample is connected to the rotating telescopic rod 10 through an external motor, thereby realizing the real-time automatic locking function of the sample. Through the above specific embodiments, the present invention can be used to smoothly carry out research on the high-temperature creep or micron particle deposition characteristics of nickel-based single crystal high-temperature alloy materials.

[0051] The above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit the same. Those skilled in the art should understand that the specific implementation methods of the present invention can be modified or replaced with equivalents with reference to the above embodiments. Any modifications or equivalent replacements that do not depart from the spirit and scope of the present invention are within the scope of protection of the pending claims.

Claims

1. A high temperature test clamping device capable of applying a variable load, characterized in that: It includes a fixed end, the fixed end is provided with a large flange for connecting to the high temperature test chamber and a fixing frame fixed on the large flange; The operating end includes a rotating bolt and a connecting rod for connecting the rotating bolt to the fixed frame, and the rotating bolt and the connecting rod are connected to each other in a relatively rotating manner; The monitoring transmission system includes a limit cylinder, a transmission shaft, a rotating motor and a sensor. The limit cylinder is movably inserted into the through hole of the small flange through a support rod at the bottom. The upper section of the through hole in the center of the limit cylinder is threadedly connected to the rotating bolt. One end of the transmission shaft is connected to the rotating motor, and the other end is connected to the rotating bolt to transmit torque. The transmission shaft and the rotating bolt can move relative to each other in the axial direction. The upper and lower ends of the sensor are respectively connected to the rotating motor and the clamping end through connecting pieces. The small flange is fixed to the large flange. The clamping end passes through the small flange and the large flange and is used to clamp the sample. The clamping end includes fixed teeth, movable teeth, an adjustment component, a fixed tooth chuck arranged on the fixed teeth, and a movable tooth chuck arranged on the movable teeth. The adjustment component is used to control the linear movement of the movable teeth relative to the fixed teeth.

2. A high temperature test clamping device capable of applying a variable load according to claim 1, characterized in that: The connecting rod is a fine-tuning rotary connecting rod with an external thread. The fine-tuning rotary connecting rod is threadedly connected to the crossbeam of the fixed frame. The pitch of the fine-tuning rotary connecting rod is smaller than the pitch of the rotating bolt.

3. A high temperature test clamping device capable of applying a variable load according to claim 2, characterized in that: A ball head is provided at the end of the fine-tuning rotary connecting rod, and a ball socket matched with the ball head is provided at the top of the rotating bolt.

4. The high temperature test clamping device capable of applying a variable load according to claim 1, characterized in that: The end of the transmission shaft is provided with a transmission head, which is inserted into the transmission groove on the end face of the rotating bolt, and the transmission head and the transmission groove are engaged for transmission.

5. The high temperature test clamping device capable of applying a variable load according to claim 4, characterized in that: The transmission shaft is a cross transmission shaft, and the cross section of the transmission head is cross-shaped; the transmission groove of the rotating bolt is a cross-shaped groove.

6. The high temperature test clamping device capable of applying a variable load according to claim 1, characterized in that: A cooling and temperature control system is provided between the sensor and the clamping end, and the cooling and temperature control system is connected to the clamping end through a rod.

7. The high temperature test clamping device capable of applying a variable load according to claim 1, characterized in that: The adjustment assembly includes a worm gear and a spiral telescopic shaft. The worm gear is fixed on the spiral telescopic shaft and is located in an operating hole set in the fixed tooth. The control end of the spiral telescopic shaft extends out of the operating hole. A rack is provided on the movable tooth, and the rack is movably set in the movable hole on the fixed tooth. The movable hole and the operating hole are arranged side by side and connected by a notch, so that the worm gear engages with the rack through the notch.

8. The high temperature test clamping device capable of applying a variable load according to claim 7, characterized in that: The fixed tooth chuck includes two fixed tooth rotating teeth rotatably connected to the bottom of the fixed teeth, and the movable tooth chuck includes two movable tooth rotating teeth rotatably connected to the bottom of the movable teeth. The fixed tooth rotating teeth and the movable tooth rotating teeth have the same structure, both of which are polygonal cylinders with multiple planes on the cylindrical surface, and patterns are provided on the cylindrical surface to increase friction.

9. The high temperature test clamping device capable of applying a variable load according to claim 8, characterized in that: The fixed tooth rotating teeth and the movable tooth rotating teeth are regular hexagonal prisms or regular octagonal prisms.

10. The high temperature test clamping device capable of applying a variable load according to claim 8, characterized in that: The movable tooth is equipped with a rotating shaft extending vertically downward, and the movable tooth rotating tooth is rotatably connected to the rotating shaft, and the rotating shaft and the movable tooth rotating tooth are axially limited; the fixed tooth is provided with a rotating handle for rotating the fixed tooth rotating tooth, and the rotating handle is connected to the fixed tooth rotating tooth through the rotating shaft passing through the fixed tooth.

Images