Electric tool impact force testing device

Abstract

The invention relates to an electric tool impact force testing device applied to the field of electric tool detection, and the device comprises a cylinder body, the inner side of the cylinder body is filled with oil, the inner side of the cylinder body is provided with a floating block, the upper end of the floating block is provided with a connecting column, the connecting column slidably penetrates through the cylinder body and is fixedly provided with an impact bearing seat, and the floating block is uniformly provided with a plurality of damping holes. The side end of the bottom of the cylinder body is provided with a measuring channel, the outer wall of the cylinder body is provided with a pressure sensor corresponding to the measuring channel, through the arrangement of the floating block, the oil and the damping hole, during testing, the electric tool impacts the impact bearing seat downwards, the oil on the lower side of the floating block is extruded upwards through the damping hole, and a large amount of impact energy is consumed in the process; therefore, the rebound of the impact energy is avoided; after the test is finished, the oil located on the upper side of the floating block flows back downwards through the damping hole under the action of the gravity of the oil, the oil floating block automatically moves upwards and floats on the upper surface of the oil to drive the strike bearing seat to stably reset, and therefore the measurement error is reduced, and the measurement accuracy is improved.

Description

Technical Field

[0001] The invention relates to an impact force testing device, in particular to an electric tool impact force testing device applied in the field of electric tool detection. Background Art

[0002] The durability of electric tools needs to be measured in one of the qualification tests to verify the fatigue life of electric tool products under normal working cycle load conditions to ensure the quality of electric tool products. As a type of electric tool, impact machinery is widely used in industrial and agricultural production, infrastructure construction and other fields. Its ultimate goal is to generate impact force to impact the object being impacted. Impact force testing is of great significance to the design, optimization and acceptance of impact machinery.

[0003] Traditional impact force testing methods include terminal velocity method, dynamometer diagram method, mechanical measurement method, nitrogen measurement method and stress wave measurement method. Although there are various measurement methods, the measurement process requires destroying the original impact force generating device and installing complex sensors inside it, which makes batch testing difficult.

[0004] In order to improve the above problems, after searching, for example, the specification of the patent publication number CN107091707B discloses an impact force test device that can simulate loads. It includes a power supply, a secondary instrument and a measuring cylinder. The measuring cylinder can be generally divided into two parts: a high-pressure measuring chamber and a low-pressure absorption chamber, and the high-pressure measuring chamber and the low-pressure absorption chamber are filled with hydraulic oil. The high-pressure measuring chamber and the low-pressure absorption chamber are separated by a partition, and an adjustable damping device is installed on the partition; the high-pressure measuring chamber is connected to the high-frequency accumulator; the low-pressure absorption chamber includes a low-pressure closed space composed of a rubber membrane and a sealing cylinder, and the closed space is filled with inert gas. By adjusting the nitrogen pressure in the nitrogen chamber of the high-frequency accumulator, the maximum measurable impact force of the entire test device can be adjusted. When the impact force acts on the stamping plate, the oil in the high-pressure measuring chamber enters the low-pressure absorption chamber through the damping hole, consuming a large amount of impact energy, thereby avoiding the rebound of the impact energy.

[0005] Based on the above search and in combination with the prior art, it is found that the existing electric tool impact force testing device utilizes elastic materials to buffer and relieve the impact during the test, such as a rubber membrane. However, as the number of tests increases, the elasticity of the rubber membrane gradually weakens, resulting in an increase in the error of the test result. Therefore, an electric tool impact force testing device is proposed to improve the above problem. Summary of the invention

[0006] In view of the above-mentioned prior art, the technical problem to be solved by the present invention is that the existing electric tool impact force testing device uses elastic materials to buffer and relieve pressure during testing, such as a rubber membrane. However, as the number of tests increases, the elasticity of the rubber membrane gradually weakens, resulting in an increase in the error of the test result.

[0007] In order to solve the above problems, the present invention provides an electric tool impact force testing device, comprising a cylinder body: The inner side of the cylinder body is filled with oil, and a floating block is vertically slidably installed on the inner side of the cylinder body. A connecting column is vertically installed at the center of the upper end of the floating block. The upper end of the connecting column slides through the cylinder body and is fixed with a striker seat. A plurality of damping holes are evenly arranged on the floating block around the connecting column, a measuring channel is arranged at the bottom side end of the cylinder body, a pressure sensor is installed on the outer wall of the cylinder body, and the measuring end of the pressure sensor is located at the inner side of the measuring channel.

[0008] In the above-mentioned electric tool impact force testing device, by setting the floating block, oil and damping hole, in the untested state, the floating block floats on the upper surface of the oil; during the test, the electric tool (such as a hydraulic breaker) impacts the impact seat downward, the impact seat is subjected to the downward impact force and moves downward with the floating block through the connecting column, and the oil on the lower side of the floating block is squeezed upward through the damping hole. The process of the oil passing through the damping hole plays an effective buffering role, consumes a large amount of impact energy, thereby avoiding the rebound of the impact energy. At the same time, the pressure sensor is used to detect the pressure value of the oil; after the test, the oil on the upper side of the floating block flows back downward through the damping hole under the action of its own gravity, and the oil floating block automatically moves up and floats on the upper surface of the oil to reset the impact seat; compared with the reset method using elastic material reset, the scheme uses the floating block to cooperate with the buoyancy of the oil to reset the impact seat to ensure that the impact seat remains stably reset, thereby reducing the measurement error and improving the measurement accuracy.

[0009] As a further supplement to the present application, there are multiple pressure sensors, and the multiple pressure sensors are evenly installed on the bottom circumference of the cylinder body. There are also multiple measurement channels, and the multiple measurement channels are arranged in a one-to-one correspondence with the multiple pressure sensors; the setting of multiple pressure sensors can effectively avoid large measurement errors caused by failure of a single pressure sensor.

[0010] As a further supplement to the present application, a protective shell cover is installed on the outer side of the bottom of the cylinder body, and a plurality of pressure sensors are located on the inner side of the protective shell cover; A protective enclosure is installed on the top of the cylinder body, and the impact seat is always located on the inner side of the protective enclosure.

[0011] As a further supplement to the present application, a replacement seat is arranged on the upper side of the striking seat, a threaded column is installed at the center of the lower end of the replacement seat, a threaded groove threadedly connected to the threaded column is arranged at the center of the upper end of the striking seat, and a notch is arranged at the side end of the replacement seat; this can prevent the striking seat from directly contacting the impact part of the power tool, and the replacement seat is convenient for replacement after being used for a period of time.

[0012] As a further supplement to the present application, a flow-changing component is installed on the inner side of the damping hole so that the flow rate of oil flowing through the damping hole from top to bottom is greater than the flow rate of oil flowing through the damping hole from bottom to top; when testing the impact force of the electric tool, the flow rate of oil flowing through the damping hole from bottom to top is smaller, ensuring that a large amount of impact energy is consumed. After the test, the flow rate of oil flowing through the damping hole from top to bottom is larger, which is convenient for the floating block to quickly reset with the impact seat.

[0013] As a further supplement to the present application, the variable flow assembly includes a fixed plate, a movable plate, a guide slide column and a limit block; The fixed plate is fixed to the inner side of the damping hole, the movable plate is located at the lower side of the fixed plate, the upper end of the guide slide is fixed to the center of the fixed plate, the lower end of the guide slide slide slides through the movable plate and is fixed to the limit block, and the guide slide is non-cylindrical; A plurality of first liquid passage holes are evenly arranged on the fixed plate, and a plurality of second liquid passage holes and a third liquid passage holes are evenly arranged on the movable plate. The plurality of second liquid passage holes are arranged corresponding to some of the first liquid passage holes, and the plurality of third liquid passage holes are staggered with the first liquid passage holes. When testing the impact force of the electric tool, the oil flows through the damping hole from bottom to top, and the movable plate approaches the fixed plate under the impact of the oil, so that the third liquid passage hole on the movable plate is sealed by the fixed plate. At the same time, some of the first liquid passage holes on the fixed plate are sealed by the movable plate, and the oil can only pass through the corresponding second liquid passage holes and the first liquid passage holes on the fixed plate and the movable plate. At this time, the flow rate is small, which can ensure the consumption of a large amount of impact energy. After the test, the oil flows through the damping hole from top to bottom, and the movable plate moves away from the fixed plate under the impact of the oil. At this time, the plurality of first liquid passage holes on the fixed plate and the plurality of second liquid passage holes and the third liquid passage holes on the movable plate are all opened, and the flow rate is large, which is convenient for the floating block to quickly reset with the impact seat.

[0014] As a further supplement to the present application, a lifting vane is provided at the inner bottom end of the cylinder body, and a linkage assembly is installed between the lifting vane and the floating block.

[0015] As a further supplement to the present application, the linkage assembly includes a pressure rod and a movable sleeve, the pressure rod is vertically fixed at the bottom center of the floating block, the movable sleeve is vertically rotatably installed at the inner bottom center of the cylinder body, and the lifting vane is fixed on the outer wall of the movable sleeve; A spiral groove is provided on the inner wall of the movable sleeve, and a sliding block that slides with the spiral groove is fixed to the bottom side end of the pressure rod; when the impact seat is subjected to the downward impact force and moves downward with the floating block through the connecting column, the pressure rod moves downward with the floating block through the sliding cooperation of the sliding block and the spiral groove, so that the movable sleeve rotates with the lifting vane, and the rotating lifting vane disturbs the oil at the bottom of the cylinder body and lifts the oil at the bottom of the cylinder body upward, eliminating the oil precipitation at the bottom of the cylinder body, which is beneficial to improve the uniformity and stability of the oil, thereby realizing full utilization of the oil.

[0016] As a further supplement to the present application, a flexible sleeve is provided on the outer side of the connecting column, and the flexible sleeve is fixed between the lower end of the impact seat and the top end of the cylinder body; the flexible sleeve can effectively prevent impurities from adhering to the surface of the connecting column, thereby reducing the wear of the connecting column during sliding.

[0017] In summary, through the setting of the floating block, oil and damping hole, in the untested state, the floating block floats on the upper surface of the oil; during the test, the electric tool (such as a hydraulic breaker) impacts the impact seat downward, the impact seat is subjected to the downward impact force and moves the floating block downward through the connecting column, the oil on the lower side of the floating block flows from bottom to top through the damping hole, and the movable plate approaches the fixed plate under the impact of the oil, so that the third liquid hole on the movable plate is sealed by the fixed plate, at the same time, part of the first liquid hole on the fixed plate is sealed by the movable plate, and the oil can only pass through the corresponding second liquid hole and the first liquid hole on the fixed plate and the movable plate. At this time, the flow rate is small, which can ensure that a large amount of impact energy is consumed, thereby avoiding the rebound of the impact energy. At the same time, as the pressure rod of the floating block moves downward, the sliding cooperation of the slider and the spiral slide groove causes the movable pipe sleeve to rotate with the lifting vane. The rotating lifting vanes disturb the oil at the bottom of the cylinder body and lift the oil at the bottom of the cylinder body upward to eliminate the oil precipitation at the bottom of the cylinder body, which is beneficial to improve the uniformity and stability of the oil, thereby achieving full utilization of the oil. During the test, a pressure sensor is used to detect the pressure value of the oil in real time; after the test, the oil located on the upper side of the floating block flows through the damping hole from top to bottom, and the movable plate moves away from the fixed plate under the impact of the oil. At this time, the multiple first liquid holes on the fixed plate and the multiple second liquid holes and the third liquid holes on the movable plate are all opened, and the flow rate is large, which is convenient for the floating block to quickly reset with the impact seat; compared with the reset method using elastic material reset, this scheme uses the floating block to cooperate with the buoyancy of the oil to reset the impact seat, which can ensure that the impact seat remains stably reset, thereby reducing measurement errors and improving measurement accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic diagram of the overall three-dimensional structure of a specific implementation method of the present application; Figure 2 It is a schematic diagram of the cutaway structure of a specific implementation method of the present application; Figure 3 It is a schematic cross-sectional structure diagram of a specific implementation method of the present application; Figure 4 A schematic diagram of a partially disassembled structure of a specific implementation method of the present application; Figure 5 It is a schematic diagram of the three-dimensional structure of the fixed disk and the movable disk of the specific implementation mode of the present application; Figure 6 It is a schematic diagram of the planar three-dimensional structure of the fixed disk and the movable disk according to a specific embodiment of the present application; Figure 7 This is a schematic diagram of the overall planar structure in an untested state in a specific implementation manner of the present application; Figure 8 This is a schematic diagram of the overall planar structure in a test state of a specific implementation method of the present application; Fig. 9 It is a three-dimensional perspective view of the linkage assembly of a specific embodiment of the present application.

[0019] Description of the numbers in the figure: 1. Cylinder body; 101. Measuring channel; 2. Strike seat; 201. Threaded groove; 3. Floating block; 301. Damping hole; 4. Connecting column; 5. Pressure sensor; 6. Variable flow assembly; 61. Fixed plate; 6101. First liquid hole; 62. Movable plate; 6201. Second liquid hole; 6202. Third liquid hole; 63. Guide slide column; 64. Limit block; 7. Pressure rod; 701. Sliding block; 8. Movable sleeve; 801. Spiral slide groove; 9. Lifting vane; 10. Protective shell cover; 11. Protective enclosure; 12. Replacement seat; 1201. Threaded column; 1202. Notch; 13. Flexible sleeve. DETAILED DESCRIPTION

[0020] The following is a detailed description of three implementation methods of the present application in conjunction with the accompanying drawings.

[0021] The first implementation method: The present invention provides an electric tool impact force testing device, see Figure 1-4 , including a cylinder body 1, the inner side of the cylinder body 1 is filled with oil, a floating block 3 is vertically slidably installed on the inner side of the cylinder body 1, a connecting column 4 is vertically installed at the center of the upper end of the floating block 3, the upper end of the connecting column 4 slides through the cylinder body 1 and is fixed with a striker seat 2, a plurality of damping holes 301 are evenly arranged on the floating block 3 around the connecting column 4, a measuring channel 101 is arranged on the bottom side end of the cylinder body 1, a pressure sensor 5 is installed on the outer wall of the cylinder body 1, and the measuring end of the pressure sensor 5 is located on the inner side of the measuring channel 101.

[0022] The electric tool impact force testing device is provided with a floating block 3, oil, and a damping hole 301. In a non-testing state, the floating block 3 floats on the upper surface of the oil. During the test, the electric tool (such as a hydraulic breaker) impacts the impact seat 2 downward, and the impact seat 2 is subjected to the downward impact force and moves downward with the floating block 3 through the connecting column 4, and the oil on the lower side of the floating block 3 is squeezed upward through the damping hole 301. The process of the oil passing through the damping hole 301 plays an effective buffering role, consumes a large amount of impact energy, thereby avoiding the rebound of the impact energy. At the same time, the pressure sensor 5 is used to detect the pressure value of the oil. After the test, the oil on the upper side of the floating block 3 flows back downward through the damping hole 301 under the action of its own gravity, and the oil floating block 3 automatically moves up and floats on the upper surface of the oil to reset the impact seat 2. Compared with the reset method using elastic material reset, the scheme uses the floating block 3 to cooperate with the buoyancy of the oil to reset the impact seat 2 to ensure that the impact seat 2 remains stably reset, thereby reducing the measurement error and improving the measurement accuracy.

[0023] Among them, the outer side of the connecting column 4 is provided with a flexible sleeve 13, and the flexible sleeve 13 is fixed between the lower end of the impact seat 2 and the top of the cylinder body 1; the set flexible sleeve 13 can effectively prevent impurities from adhering to the surface of the connecting column 4, thereby reducing the wear of the connecting column 4 during the sliding process.

[0024] Among them, there are multiple pressure sensors 5, and the multiple pressure sensors 5 are evenly installed on the bottom circumference of the cylinder body 1. There are also multiple measuring channels 101, and the multiple measuring channels 101 are arranged one-to-one correspondingly to the multiple pressure sensors 5. The setting of multiple pressure sensors 5 can effectively avoid large measurement errors caused by failure of a single pressure sensor 5.

[0025] Among them, a protective shell cover 10 is installed on the outer side of the bottom of the cylinder body 1, and multiple pressure sensors 5 are located on the inner side of the protective shell cover 10. A protective enclosure 11 is installed on the top of the cylinder body 1, and the impact seat 2 is always located on the inner side of the protective enclosure 11.

[0026] Among them, a replacement seat 12 is arranged on the upper side of the striking seat 2, a threaded column 1201 is installed at the center of the lower end of the replacement seat 12, a threaded groove 201 threadedly connected to the threaded column 1201 is arranged at the center of the upper end of the striking seat 2, and a notch 1202 is arranged at the side end of the replacement seat 12 to prevent the striking seat 2 from directly contacting the impact part of the power tool. The replacement seat 12 is arranged for easy replacement after being used for a period of time.

[0027] Second implementation method: Based on the first embodiment, the present embodiment adds the following structure, so that the present application can effectively consume a large amount of impact energy while ensuring that the striker 2 can be quickly reset. The specific configuration is as follows: Figure 5-8As shown, a flow-changing component 6 is installed on the inner side of the damping hole 301, so that the flow rate of oil flowing through the damping hole 301 from top to bottom is greater than the flow rate of oil flowing through the damping hole 301 from bottom to top, so that when testing the impact force of the electric tool, the flow rate of oil flowing through the damping hole 301 from bottom to top is smaller, ensuring that a large amount of impact energy is consumed. After the test, the flow rate of oil flowing through the damping hole 301 from top to bottom is larger, which is convenient for the floating block 3 to quickly reset with the impact seat 2.

[0028] Specifically, Figure 5 and Figure 6 It is shown that the variable flow assembly 6 includes a fixed plate 61, a movable plate 62, a guide slide 63 and a limit block 64. The fixed plate 61 is fixed to the inner side of the damping hole 301, and the movable plate 62 is located on the lower side of the fixed plate 61. The upper end of the guide slide 63 is fixed to the center of the fixed plate 61, and the lower end of the guide slide 63 slides through the movable plate 62 and is fixed to the limit block 64. The guide slide 63 is non-cylindrical, and a plurality of first liquid holes 6101 are evenly arranged on the fixed plate 61, and a plurality of second liquid holes 6201 and third liquid holes 6202 are evenly arranged on the movable plate 62. The plurality of second liquid holes 6201 are arranged corresponding to some of the first liquid holes 6101, and the plurality of third liquid holes 6202 are staggered with the first liquid holes 6101.

[0029] Based on the coordinated arrangement of the above structure, when testing the impact force of the electric tool, the oil flows through the damping hole 301 from bottom to top, and the movable disk 62 approaches the fixed disk 61 under the impact of the oil, so that the third liquid hole 6202 on the movable disk 62 is sealed by the fixed disk 61. At the same time, part of the first liquid holes 6101 on the fixed disk 61 is sealed by the movable disk 62, and the oil can only pass through the corresponding second liquid holes 6201 and the first liquid holes 6101 on the fixed disk 61 and the movable disk 62. At this time, the flow rate is small, which can ensure that a large amount of impact energy is consumed; after the test, the oil flows through the damping hole 301 from top to bottom, and the movable disk 62 moves away from the fixed disk 61 under the impact of the oil. At this time, the multiple first liquid holes 6101 on the fixed disk 61 and the multiple second liquid holes 6201 and the third liquid holes 6202 on the movable disk 62 are all opened, and the flow rate is large, which is convenient for the floating block 3 to quickly reset with the impact seat 2.

[0030] The third implementation method: Based on Embodiment 1 and Embodiment 2, this embodiment adds the following structure, so that the present application can improve the uniformity and stability of the oil, and the specific configuration is as follows: Figure 4 and Fig. 9As shown, a lifting vane 9 is provided at the inner bottom end of the cylinder body 1, and a linkage assembly is installed between the lifting vane 9 and the floating block 3. Specifically, the linkage assembly includes a pressure rod 7 and a movable sleeve 8. The pressure rod 7 is vertically fixed at the bottom center of the floating block 3, and the movable sleeve 8 is vertically rotatably installed at the inner bottom center of the cylinder body 1. The lifting vane 9 is fixed on the outer wall of the movable sleeve 8, and a spiral groove 801 is provided on the inner wall of the movable sleeve 8. A slider 701 that slides with the spiral groove 801 is fixed to the bottom side end of the pressure rod 7.

[0031] Based on the coordination setting of the above structure, when the impact seat 2 is subjected to the downward impact force and moves downward with the floating block 3 through the connecting column 4, the pressure rod 7 as the floating block 3 moves downward cooperates with the sliding of the slider 701 and the spiral slide groove 801, so that the movable pipe sleeve 8 rotates with the lifting vane 9. The rotating lifting vane 9 disturbs the oil at the bottom of the cylinder body 1 and lifts the oil at the bottom of the cylinder body 1 upward to eliminate the oil precipitation at the bottom of the cylinder body 1. At the same time, the oil can be further squeezed and mixed in cooperation with the liquid hole, which is beneficial to improve the uniformity and stability of the oil, thereby realizing full utilization of the oil.

[0032] In view of current practical needs, the above-mentioned implementation mode adopted in this application is not limited to the scope of protection. Various changes made within the knowledge scope of technical personnel in this field without departing from the concept of this application still fall within the scope of protection of the present invention.

Claims

1. An electric tool impact force testing device, comprising a cylinder (1), characterized in that: The inner side of the cylinder body (1) is filled with oil, a floating block (3) is vertically slidably mounted on the inner side of the cylinder body (1), a connecting column (4) is vertically mounted at the center of the upper end of the floating block (3), the upper end of the connecting column (4) slides through the cylinder body (1) and is fixed with a striker seat (2); A plurality of damping holes (301) are evenly arranged on the floating block (3) around the connecting column (4), a measuring channel (101) is arranged at the bottom side end of the cylinder body (1), a pressure sensor (5) is installed on the outer wall of the cylinder body (1), and a measuring end of the pressure sensor (5) is located on the inner side of the measuring channel (101).

2. The electric tool impact force testing device according to claim 1, characterized in that: A plurality of the pressure sensors (5) are provided, and the plurality of the pressure sensors (5) are evenly installed on the bottom circumference of the cylinder body (1). A plurality of the measuring channels (101) are also provided, and the plurality of the measuring channels (101) are arranged in a one-to-one correspondence with the plurality of the pressure sensors (5).

3. The electric tool impact force testing device according to claim 2, characterized in that: A protective shell (10) is installed on the outer side of the bottom of the cylinder (1), and the plurality of pressure sensors (5) are all located on the inner side of the protective shell (10); A protective enclosure (11) is installed on the top of the cylinder body (1), and the impact seat (2) is always located inside the protective enclosure (11).

4. The electric tool impact force testing device according to claim 3, characterized in that: A replacement seat (12) is arranged on the upper side of the strike seat (2), a threaded column (1201) is installed at the center of the lower end of the replacement seat (12), a threaded groove (201) threadedly connected to the threaded column (1201) is arranged at the center of the upper end of the strike seat (2), and a notch (1202) is arranged at the side end of the replacement seat (12).

5. The electric tool impact force testing device according to claim 1, characterized in that: A flow-changing component (6) is installed inside the damping hole (301) so that the flow rate of the oil flowing through the damping hole (301) from top to bottom is greater than the flow rate of the oil flowing through the damping hole (301) from bottom to top.

6. The electric tool impact force testing device according to claim 5, characterized in that: The variable flow assembly (6) comprises a fixed disk (61), a movable disk (62), a guide sliding column (63) and a limit block (64); The fixed plate (61) is fixed to the inner side of the damping hole (301), the movable plate (62) is located at the lower side of the fixed plate (61), the upper end of the guide slide column (63) is fixed to the center of the fixed plate (61), the lower end of the guide slide column (63) slides through the movable plate (62) and is fixed to the limit block (64), and the guide slide column (63) is non-cylindrical; The fixed disk (61) is evenly provided with a plurality of first liquid passage holes (6101), and the movable disk (62) is evenly provided with a plurality of second liquid passage holes (6201) and third liquid passage holes (6202), wherein the plurality of second liquid passage holes (6201) are arranged corresponding to a portion of the first liquid passage holes (6101), and the plurality of third liquid passage holes (6202) are staggered with the first liquid passage holes (6101).

7. The electric tool impact force testing device according to claim 1, characterized in that: A lifting vane (9) is provided at the inner bottom end of the cylinder body (1), and a linkage assembly is installed between the lifting vane (9) and the floating block (3).

8. The electric tool impact force testing device according to claim 7, characterized in that: The linkage assembly comprises a pressure rod (7) and a movable sleeve (8), wherein the pressure rod (7) is vertically fixed at the bottom center of the floating block (3), the movable sleeve (8) is vertically rotatably mounted at the inner bottom center of the cylinder body (1), and the lifting vane (9) is fixed on the outer wall of the movable sleeve (8); A spiral groove (801) is provided on the inner wall of the movable sleeve (8), and a sliding block (701) that slidably cooperates with the spiral groove (801) is fixed to the bottom side end of the pressure rod (7).

9. The electric tool impact force testing device according to claim 1, characterized in that: The outer side of the connecting column (4) is provided with a flexible sleeve (13), and the flexible sleeve (13) is fixed between the lower end of the impact seat (2) and the top end of the cylinder body (1).

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