A chair back reclining force value testing apparatus
By using first and second tilt sensors in the chair back tilt force testing device, adjusting the traction belt to be perpendicular to the chair back, and combining lifting and linear drive mechanisms, the problem of inaccurate testing in the prior art is solved, and more efficient and accurate test results are achieved.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- UE FURNITURE CO LTD
- Filing Date
- 2025-05-28
- Publication Date
- 2026-06-23
AI Technical Summary
In existing technologies, the testing of chair back tilt force is not accurate enough, and it is difficult to ensure that the direction of the pull force is perpendicular to the chair back, resulting in deviations in the test results.
A first tilt sensor monitors the tilt angle change of the chair back clamp, and a second tilt sensor monitors the tilt angle change of the traction belt. The traction belt is adjusted to be perpendicular to the chair back by an adjusting seat. Combined with the force sensor to measure the force value, the movement of the test platform is adjusted by a lifting drive mechanism and a linear drive mechanism to ensure test accuracy.
This improved the accuracy of chair back tilt force testing, reduced the impact of angle deviation on test results, and enhanced the applicability and testing efficiency of the equipment.
Smart Images
Figure CN224398958U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of chair testing technology, and in particular to a chair back tilt force testing device. Background Technology
[0002] The tilt force of a chair refers to the supporting force exerted on the human body by the chair back at different tilt angles. The magnitude of this force can affect the comfort of the human body when leaning back against the chair back and when getting up. Testing the tilt force of chairs often requires testing equipment. Existing technology, such as the Chinese utility model patent with authorization announcement number CN221078073U, discloses an office chair backrest fatigue testing machine. This machine includes a workbench with a seat fixing fixture on its surface. One side of the fixture has a limit plate, and a support frame is vertically mounted on one side of the workbench. Inside the support frame, a first connecting frame is vertically mounted. A connecting seat is located at the connection between the first connecting frame and the support frame. A cylinder is mounted on the side of the connecting seat, and a sensor is driven at the bottom of the cylinder. A pull strap is mounted on one side of the sensor, and the other end of the pull strap is attached to the seat fixing fixture. When the seat fixing fixture is fixed to the back of the chair to be tested, the cylinder pulls the pull strap, causing the fixture to continuously pull the chair back backward, simulating the state of a person leaning back while sitting in an office. The sensor can reflect the magnitude of the pulling force.
[0003] However, the aforementioned testing machine is not accurate enough in testing the backrest tilt force. Utility Model Content
[0004] The purpose of this invention is to solve the problems existing in the prior art and provide a chair back tilt force testing device that can accurately test the tilt force of chairs.
[0005] The objective of this utility model is achieved through the following technical solution:
[0006] A chair back tilt force testing device includes a test platform, a seat fixing mechanism, a traction mechanism, a traction belt, a chair back clamp, and a human body simulated counterweight. The seat fixing mechanism is located on the test platform, the traction mechanism is located on one side of the test platform, the traction belt is located between the traction mechanism and the chair back clamp, and a tension sensor is provided at one end of the traction belt. The traction mechanism includes a traction motor, a swing arm located at the output end of the traction motor, an adjustment seat slidably connected to the swing arm, and a lifting drive mechanism on the swing arm that drives the adjustment seat to rise and fall. One end of the traction belt is connected to the adjustment seat. A first tilt sensor is provided on the chair back clamp, and a second tilt sensor is provided on the traction belt.
[0007] Preferably, the lifting drive mechanism includes a lifting motor, a lifting screw located at the output end of the lifting motor, and a lifting nut located on the adjusting seat. The lifting screw is threadedly connected to the lifting nut, and the lifting screw is along the length direction of the swing arm.
[0008] Preferably, the swing arm includes two columns spaced apart, the lifting motor is located at the upper end of the two columns, and the lifting screw is located between the two columns.
[0009] Preferably, the upper and lower sides of the adjustment seat are provided with limit trigger plates, and the upper and lower parts of the swing arm are provided with micro switches that cooperate with the limit trigger plates.
[0010] Preferably, the traction belt is provided with a sensor mounting structure, which includes a corner piece and a clamping plate. The clamping plate and the corner piece are connected to each other and clamped tightly on the traction belt. The second tilt sensor is located on the side of the corner piece.
[0011] Preferably, the sensor mounting structure further includes an adjustment plate, which is located between the corner piece and the second tilt sensor. The adjustment plate and the corner piece are provided with two sets of matching connection holes, one of which is an arc-shaped hole.
[0012] Preferably, one end of the traction belt connected to the chair back clamp is provided with an angle observation piece, one end of the angle observation piece is provided with a reference groove, and observation openings are opened on the front and rear sides of the reference groove. One end of the traction belt extends into the middle of the upper and lower sides of the reference groove and is connected to the angle observation piece.
[0013] Preferably, the test bench includes a base, a platform slidably connected to the base, and a linear drive mechanism disposed between the base and the platform, wherein the platform moves in a direction toward or away from the traction mechanism.
[0014] Preferably, the linear drive mechanism includes a linear motor, a linear screw connected to the output end of the linear motor, and a linear nut located at the bottom of the platform.
[0015] Preferably, the chair back clamp includes two clamping rods that clamp each other to the front and rear sides of the chair back, and the tension sensor is vertically connected to the side of one of the clamping rods.
[0016] The advantages of this utility model are:
[0017] 1. The first tilt sensor monitors the tilt angle change of the chair back clamp, i.e., the chair back, and the second tilt sensor monitors the tilt angle change of the traction belt. Based on this, the traction belt is adjusted to always be perpendicular to the chair back using the adjustment seat, thereby ensuring the accuracy of the tilt force value test.
[0018] 2. The angle observation piece makes it easier for testers to detect deviations in the angle of the traction belt in a timely manner, ensuring the accuracy of the traction force direction and thus guaranteeing the accuracy of the test results;
[0019] 3. The platform's movable adjustment mechanism ensures the applicability of the testing equipment to different types of chairs. Attached Figure Description
[0020] Figure 1 A schematic diagram of a chair back tilt force testing device provided in the embodiments of this specification;
[0021] Figure 2 for Figure 1 Enlarged structural diagram at point A;
[0022] Figure 3 for Figure 1 Enlarged structural diagram at point B;
[0023] Figure 4 This is a schematic diagram of the connection structure between the chair back clamp and the traction belt provided in the embodiments of this specification;
[0024] Figure 5 for Figure 4 Enlarged structural diagram at point C;
[0025] Figure 6 This is a structural schematic diagram of the angle observation device provided in the embodiments of this specification;
[0026] Figure 7 This is a schematic diagram of the traction mechanism provided in the embodiments of this specification. Detailed Implementation
[0027] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.
[0028] As mentioned in the background section, although the testing machine can adjust the tension angle of the strap through the positioning pulley, it is difficult to adjust the tension angle of the strap to be perpendicular to the chair back, which leads to deviations in the tension test.
[0029] Therefore, such as Figure 1 , 2As shown in Figure 7, this embodiment provides a chair back tilt force testing device, including a test platform 1, a seat fixing mechanism 2, a traction mechanism 3, a traction belt 4, a chair back clamp 5, a tension sensor 6, and a human body simulated counterweight 7. The seat fixing mechanism 2 is located on the test platform 1 and is used to fix the lower part of the chair to prevent it from moving, but without affecting the normal tilt of the chair back. The human body simulated counterweight 7 is placed on the chair seat to simulate the pressure exerted on the chair seat by people of different weights, ensuring the accuracy of the test. The chair back clamp 5 is used to clamp onto the chair back to provide a stable connection point. The tension sensor 6 is vertically installed on the side of the chair back clamp 5 to ensure that the direction of the tension is perpendicular to the chair back. The traction mechanism 3 is located on one side of the test platform 1 and includes a traction motor 31, a swing arm 32 located at the output end of the traction motor 31, an adjusting seat 33 slidably connected to the swing arm 32, and a lifting drive mechanism on the swing arm 32 to drive the adjusting seat 33 to rise and fall. One end of the traction belt 4 is connected to the adjusting seat 33, and the other end is connected to the tension sensor 6. The traction mechanism 3 pulls the traction belt 4 by swinging the swing arm 32, thereby pulling the chair back. The adjusting seat 33 is used to adjust the tilt angle of the traction belt 4 to ensure that the direction of the pulling force is perpendicular to the chair back. The chair back clamp 5 is equipped with a first tilt angle sensor 81 to obtain the tilt angle of the chair back, and the traction belt 4 is equipped with a second tilt angle sensor 82 to obtain the tilt angle of the traction belt.
[0030] Thus, the operating principle of this testing equipment is as follows: First, the back of the chair 9 faces the traction mechanism 3, and the chair 9 is fixed on the test table 1 using the seat fixing mechanism 2. Then, the backrest clamp 5 is clamped on the backrest. At this time, the backrest is in the initial state, and the measurement value of the first tilt sensor 81 is the initial angle of the backrest. Through the movement of the swing arm 32 and the movement of the adjusting seat 33, the traction belt 4 is taut and perpendicular to the backrest clamp 5. At this time, the measurement value of the second tilt sensor 82 is the initial angle of the traction belt 4. Subsequently, the chair back is gradually pulled backward by the traction mechanism 3. The first tilt sensor 81 accurately controls the tilt angle of the chair back, precisely achieving the required tilt angle for measurement. Then, the angle of the traction belt 4 is adjusted to be perpendicular to the chair back clamp 5. The adjustment process only requires that the change in the measured value of the second tilt sensor 82 be equal to the change in the measured value of the first tilt sensor 81. The adjustment is accurate and efficient. At this point, the force value measured by the tension sensor 6 is the chair back tilt force value at the corresponding angle. According to the testing needs, the force value at any tilt angle can be tested. Since the direction of the tension can be accurately adjusted to be perpendicular to the chair back, the measurement result is highly accurate. It should be noted that due to the existence of various errors, the above-mentioned perpendicularity of the tension direction to the chair back refers to theoretical perpendicularity, not absolute perpendicularity. It should also be noted that slight deviations in angle will not significantly affect the test results. Therefore, in actual testing, an acceptable angle range is generally set, for example, the angle between the traction belt and the chair back can be within 90°±5°. This also reduces the difficulty of adjusting the angle of the traction belt and improves the overall testing efficiency.
[0031] Specifically, to improve ease of use, the first tilt sensor 81 and the second tilt sensor 82 can be preset to the same initial state, such as... Figure 2 As shown, for example, if the initial state of the chair back is vertical, and the direction of the pulling force of the traction belt 4 needs to be perpendicular to the chair back, then the initial state of the traction belt 4 is horizontal. The first tilt sensor 81 and the second tilt sensor 82 are respectively set on the side of the chair back clamp 5 and the traction belt 4. It can be seen that at this time, the states of the two tilt sensors are consistent, and the measured values are the same. When the chair back is tilted, in order to make the pulling force of the traction belt 4 perpendicular to the chair back, the measured values of the two tilt sensors need to be consistent. That is, when adjusting the angle of the traction belt 4, it is only necessary to make the measured value of the second tilt sensor 82 the same as the measured value of the first tilt sensor 81.
[0032] like Figure 4 and 5As shown, to install the second tilt sensor 82 on the side of the traction belt 4, the traction belt 4 is provided with a sensor mounting structure. The sensor mounting structure includes corner brackets and a clamping plate 101. The corner brackets include a horizontal plate 102 and a vertical plate 103. The clamping plate 101 and the horizontal plate 102 are connected to each other by bolts and clamped to the upper and lower sides of the traction belt 4. The second tilt sensor 82 can then be set on the vertical plate 103, thus maintaining the same state as the first tilt sensor 81. To balance the error, an adjustment plate 104 is provided between the vertical plate 103 and the second tilt sensor 82. The adjustment plate 104 has two connecting holes, one of which is an arc-shaped hole 1041 centered on the other connecting hole. The vertical plate 103 has two conventional connecting holes. In this way, the installation angle of the adjustment plate 104 and the second tilt sensor 82 can be finely adjusted using the arc-shaped hole 1041, and then tightened with bolts and nuts to ensure the accuracy of the initial state of the second tilt sensor 82.
[0033] like Figure 6 As shown, to facilitate timely detection of angle abnormalities in the traction belt 4 by testers, an angle observation device is provided between the tension sensor 6 and the traction belt 4. The angle observation device includes a connecting seat 111 and reference plates 112 located on opposite sides of the connecting seat 111. The connecting seat 111 is connected to the tension sensor 6 by bolts. The two reference plates 112 extend towards the traction belt 4, forming a reference groove 113 between them. The front and rear sides of the reference groove 113 are open, serving as observation ports. One end of the traction belt 4 extends between the two reference plates 112 and is connected to a connecting shaft located in the middle of the connecting seat 111. Thus, since the tension sensor 6 is perpendicularly connected to the chair back clamp 5, when the direction of the traction belt 4 is also perpendicular to the chair back clamp 5, it is on the same straight line as the tension sensor 6. At this time, the traction belt 4 is located in the middle position of the two reference plates 112. Once the traction belt 4 approaches or contacts one of the reference plates, it indicates that the angle of the traction belt is abnormal and needs to be adjusted. Alternatively, the range between the two reference plates 112 can be used as the acceptable range of traction belt angle deviation. As long as the traction belt 4 does not contact either reference plate, the deviation is considered to be within the acceptable range, and the test proceeds normally. Once the traction belt 4 contacts one of the reference plates, adjustment is required.
[0034] The following describes the structure of other parts of the testing equipment, such as... Figure 3 As shown, the seat fixing mechanism 2 has a relatively conventional structure, mainly including a pressure ring 21, multiple fixing screws 22 vertically mounted on the test platform 1, and a fixing handwheel 23 threadedly connected to the fixing screws 22. The pressure ring 21 has a notch for engaging the chair's gas spring. In use, the pressure ring 21 is pressed against the chair's five-claw mechanism, and then the fixing handwheel 23 is used to press the pressure ring 21 downwards, thus achieving the clamping and fixing of the pressure ring to the five-claw mechanism. Figure 4As shown, the structure of the chair back clamp 5 is also relatively conventional, mainly including two clamping rods 51, two clamping screws 52 connecting the two clamping rods 51, clamping nuts and clamping handwheels 53 located at both ends of the clamping screws 52. In use, the two clamping rods 51 are clamped on the front and back sides of the chair back respectively, and then the clamping nuts and clamping handwheels 53 are used to pull the distance between the two clamping rods 51 closer until the chair back is clamped.
[0035] like Figure 7 As shown, the lifting drive mechanism includes a lifting motor 341, a lifting screw 342 located at the output end of the lifting motor 341, and a lifting nut 343 located on the adjusting seat 33. The lifting screw 342 is threadedly connected to the lifting nut 343, and the lifting screw 342 extends along the length of the swing arm 32. The rotation of the lifting screw drives the lifting nut and the adjusting seat to rise and fall, ensuring stable and reliable lifting and adjustment. The swing arm 32 includes two spaced columns 321. The lifting motor 341 is located at the upper end of the two columns 321, and the lifting screw 342 is located between the two columns 321 to avoid interference between the lifting screw and external components, and also to facilitate the installation of the lifting motor. To ensure equipment safety, limit trigger plates 344 are provided on both the upper and lower sides of the adjusting seat 33, and micro switches 345 that cooperate with the limit trigger plates 344 are provided on both the upper and lower parts of the swing arm 32 to prevent the movement of the adjusting seat from exceeding the safe range.
[0036] like Figure 1 As shown, since the length of the traction belt is fixed, to improve the applicability of this device to chairs of different specifications, the test bench 1 includes a base 11, a platform 12 slidably connected to the base 11, and a linear drive mechanism located between the base 11 and the platform 12. The platform moves towards or away from the traction mechanism. The linear drive mechanism includes a linear motor, a linear screw 13 driven to the output end of the linear motor, and a linear nut located at the bottom of the platform. In this way, the distance between the chair and the traction mechanism can be adjusted to meet the testing requirements of chairs of different specifications.
[0037] The above are merely preferred embodiments of this utility model, and are implementations based on the overall concept of this utility model. Furthermore, the scope of protection of this utility model is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this utility model should be included within the scope of protection of this utility model. Therefore, the scope of protection of this utility model should be determined by the scope of the claims.
Claims
1. A chair back tilt force testing device, comprising a test platform, a seat fixing mechanism, a traction mechanism, a traction belt, a chair back clamp, and a human body simulated counterweight, wherein the seat fixing mechanism is disposed on the test platform, the traction mechanism is disposed on one side of the test platform, the traction belt is disposed between the traction mechanism and the chair back clamp, and a tension sensor is provided at one end of the traction belt, characterized in that, The traction mechanism includes a traction motor, a swing arm located at the output end of the traction motor, an adjustment seat slidably connected to the swing arm, and a lifting drive mechanism on the swing arm that drives the adjustment seat to rise and fall. One end of the traction belt is connected to the adjustment seat. A first tilt sensor is provided on the chair back clamp, and a second tilt sensor is provided on the traction belt.
2. The chair back tilt force testing device according to claim 1, characterized in that, The lifting drive mechanism includes a lifting motor, a lifting screw located at the output end of the lifting motor, and a lifting nut located on the adjusting seat. The lifting screw and the lifting nut are threadedly connected, and the lifting screw is along the length direction of the swing arm.
3. The chair back tilt force testing device according to claim 2, characterized in that, The swing arm includes two columns spaced apart, the lifting motor is located at the upper end of the two columns, and the lifting screw is located between the two columns.
4. The chair back tilt force testing device according to claim 1, characterized in that, The upper and lower sides of the adjustment seat are provided with limit trigger plates, and the upper and lower parts of the swing arm are provided with micro switches that cooperate with the limit trigger plates.
5. The chair back tilt force testing device according to claim 1, characterized in that, The traction belt is equipped with a sensor mounting structure, which includes a corner piece and a clamping plate. The clamping plate and the corner piece are connected to each other and clamped tightly to the traction belt. The second tilt sensor is located on the side of the corner piece.
6. The chair back tilt force testing device according to claim 5, characterized in that, The sensor mounting structure also includes an adjustment plate, which is located between the corner piece and the second tilt sensor. The adjustment plate and the corner piece are provided with two sets of matching connection holes, one of which is an arc-shaped hole.
7. The chair back tilt force testing device according to claim 1, characterized in that, An angle observation piece is provided at one end of the traction belt connected to the chair back clamp. A reference groove is provided at one end of the angle observation piece. Observation ports are opened on the front and rear sides of the reference groove. One end of the traction belt extends into the middle of the upper and lower sides of the reference groove and is connected to the angle observation piece.
8. The chair back tilt force testing device according to claim 1, characterized in that, The test bench includes a base, a platform slidably connected to the base, and a linear drive mechanism disposed between the base and the platform. The platform moves in a direction close to or away from the traction mechanism.
9. The chair back tilt force testing device according to claim 8, characterized in that, The linear drive mechanism includes a linear motor, a linear screw connected to the output end of the linear motor, and a linear nut located at the bottom of the platform.
10. The chair back tilt force testing device according to claim 1, characterized in that, The chair back clamp includes two clamping rods that clamp each other to the front and rear sides of the chair back, and the tension sensor is vertically connected to the side of one of the clamping rods.