Elastic force control device based on stepping motor
By using a stepper motor-based elastic force control device, the problem of pressure deviation in the pressure head tooling during display panel testing was solved, achieving low-cost, precise force control and overload protection to prevent damage to the display panel.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-01-22
- Publication Date
- 2026-03-27
AI Technical Summary
In existing display panel testing devices, the actual pressure of the pressure head fixture deviates from the theoretical pressure, which may cause damage to the display panel. Furthermore, the existing technology is costly and lacks overload protection.
An elastic force control device based on a stepper motor is adopted, which uses the stepper motor as a power source and combines it with an elastic buffer structure. Through the design of compression springs and pressure heads, precise force control and prevention of crushing injuries are achieved.
It achieves precise force control at a low cost, prevents damage to the display panel, and provides buffer protection in case of overload.
Smart Images
Figure CN224053603U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model is applied to the technical field of pressure test, and particularly relates to an elastic force control device based on a stepping motor. BACKGROUND
[0002] With the rapid development of display panel technology, display panels have been widely applied to display instruments such as mobile phones, computers and televisions. The preparation of display panels includes multiple different process stages, and display panels need to be detected at each process stage. Currently, after the display panel completes the Cell manufacturing stage, a FPC false pressure method is usually used for lighting detection, that is, a set of pressure head tooling is used to ensure the crimping of the FPC and the display panel conductive contact. The upper end surface of the common pressure head tooling is connected with a spring, and the lower end surface is attached with a buffer pad (which can be made of rubber or other materials). The pressure head can be self-locked to ensure the crimping of the FPC and the display panel conductive contact. Since the stroke ΔH of the pressure head is determined, when the elastic modulus k is determined, the pressure F generated by the pressure head tooling on the display panel contact is ΔH*k. However, since the k value of the pressure head tooling at the design stage is the direct linear superposition of the elastic modulus of the spring and the elastic modulus of the buffer pad, the actual pressure generated by the tooling will deviate from the theoretically designed pressure, which may result in a situation where the actual pressure is greater than the theoretical pressure. When the pressure of the pressure head is too large, it will cause the display panel to be pressed and affect the next manufacturing crimping of the display panel conductive contact. Therefore, it is urgent to solve the technical problem of reasonably controlling the pressure of the pressure head tooling.
[0003] Since the structure of the lower pressure is rigid, the measured product is easily deformed by the load. Once overloaded, it will cause pressure injury to the surface of the measured product. Although a servo motor or a voice coil motor can accurately control the pressure of the pressing structure, the cost of the servo motor is significantly higher than that of the stepping motor, and the cost of the voice coil motor is several times that of the stepping motor, which is too high. Moreover, the rigid structure has no overload protection, and once the motor overshoots during debugging or testing, it is easy to cause damage to the measured product. Therefore, it is necessary to provide an elastic force control device based on a stepping motor, which has low cost, uses an elastic buffer structure, and can prevent the measured product from being pressed. Utility model content
[0004] The utility model solves the technical problems of the prior art and provides an elastic force control device based on a stepping motor, which has low cost, uses an elastic buffer structure, and can prevent the measured product from being pressed.
[0005] The utility model discloses a technical scheme adopted is: the utility model discloses including the mounting panel, the mounting panel is provided with a plurality of step motor along the vertical direction is established, the output shaft transmission of step motor is connected with the screw rod, the screw rod slidingly arranged with L shape mounting block, the bottom of L shape mounting block is provided with pressure sensor, the bottom of pressure sensor is connected with T shape mounting block, T shape mounting block is provided with the through -hole, the through -hole is provided with compression spring and pressure head, T shape mounting block passes through compression spring and pressure head top pressure cooperation, the pressure head passes through the bottom of T shape mounting block and product press -fitting.
[0006] From the above scheme, the step motor is used as the power source of the pressing, and the cost is low, and the T-shaped mounting block provides an elastic buffer structure, thereby preventing the measured product from being crushed. Not only can the pressing stroke of the step motor be controlled, but also the pressure head can be smoothly slid up and down.
[0007] One preferred scheme is that the compression spring is a flat bottom spring, the pressure head is a T-shaped cylindrical head, the diameter of the upper end of the T-shaped cylindrical head is greater than the diameter of the lower end of the T-shaped cylindrical head, the upper hole diameter of the through hole is greater than the lower hole diameter of the through hole, the diameter of the upper end of the T-shaped cylindrical head is matched with the upper hole diameter of the through hole, the diameter of the lower end of the T-shaped cylindrical head is matched with the lower hole diameter of the through hole, the bottom of the flat bottom spring is flush structure, and the flush structure is in contact with the top of the T-shaped cylindrical head.
[0008] One preferred scheme is that the top of the T-shaped mounting block is provided with a cover plate, and the cover plate is in top bracing cooperation with the top of the flat bottom spring.
[0009] One preferred scheme is that the number of step motors is four, and the four step motors are arranged side by side on the panel of the mounting plate.
[0010] One preferred scheme is that the elastic force control device based on the step motor further comprises a rack and a sliding frame, the top of the rack is provided with two groups of symmetrically arranged linear guides, the linear guides are slidingly provided with sliding blocks, the sliding frame is arranged on the top of the sliding blocks, the mounting plate is arranged on the sliding frame, the sliding frame is connected with the action end of an external linear module, and a profiling groove matched with the product is arranged between the two groups of linear guides.
[0011] One preferred scheme is that the end of the linear guide is provided with a buffer, and the buffer is in limiting cooperation with the sliding block.
[0012] One preferred scheme is that the profiling groove is provided with a positioning pin, and the positioning pin is in positioning cooperation with the product. BRIEF DESCRIPTION OF DRAWINGS
[0013] Figure 1 is a perspective view of the utility model;
[0014] Figure 2 is a perspective view of the utility model;
[0015] Figure 3 is a sectional view of the T-shaped mounting block. DETAILED DESCRIPTION
[0016] As Figure 2 and Figure 3 shown, in this embodiment, the utility model includes mounting plate 1, the mounting plate 1 is provided with several step motors 2 along the vertical direction, the output shaft of step motor 2 is drivenly connected with lead screw 3, the lead screw 3 is slidably provided with L-shaped mounting block 4, the bottom of L-shaped mounting block 4 is provided with pressure sensor 5, the bottom of pressure sensor 5 is connected with T-shaped mounting block 6, T-shaped mounting block 6 is provided with through hole, the through hole is provided with compression spring 7 and pressure head 8, T-shaped mounting block 6 is top-pressed with pressure head 8 through compression spring 7, pressure head 8 is pressed with product through the bottom of T-shaped mounting block 6.
[0017] Step motor 2 is used for controlling the downward pressure or load of pressure head 8, mounting plate 1 is used for mounting step motor 2, L-shaped mounting block 4 is used for connecting step motor 2 and pressure head 8, pressure sensor 5 is used for monitoring and feeding the load force of downward pressure, compression spring 7 is used as overload buffer, T-shaped mounting block 6 is used for mounting pressure head 8 and compression spring 7, pressure head 8 directly contacts product and applies load to product, wherein product refers to the product to be tested.
[0018] As Figure 2 and Figure 3 shown, in this embodiment, the compression spring 7 is a flat bottom spring, the pressure head 8 is a T-shaped cylindrical head, the diameter of the upper end of the T-shaped cylindrical head is greater than the diameter of the lower end of the T-shaped cylindrical head, the diameter of the upper hole of the through hole is greater than the diameter of the lower hole of the through hole, the diameter of the upper end of the T-shaped cylindrical head is matched with the diameter of the upper hole of the through hole, the diameter of the lower end of the T-shaped cylindrical head is matched with the diameter of the lower hole of the through hole, the bottom of the flat bottom spring is flush structure, and the flush structure is in contact with the top of the T-shaped cylindrical head.
[0019] Since the pressure head 8 will retract during the loading process, the compression bending caused by the uneven gap and spring during the retraction process will cause the pressure head 8 to be skewed due to uneven force during the compression of the compression spring 7, eventually causing the pressure head 8 to rub against the T-shaped mounting block 6, so that the pressure head 8 retracts smoothly, or even directly causes the elastic buffer to fail; The application adopts a customized flat spring to ensure that the pressure head 8 is uniformly stressed, and at the same time, the unilateral gap between the pressure head 8 and the T-shaped mounting block 6 is reduced to 0.1mm, ensuring that the pressure head 8 can smoothly slide up and down.
[0020] If the compression spring 7 uses a common spring, the two ends of the common spring are uneven, and the surface of the pressure head 8 is flat. During compression, the flat and non-flat contact will cause uneven force, resulting in skew, which will cause the lower part of the pressure head 8 to rub against the T-shaped mounting block 6, and then the pressure head 8 will be stuck at the bottom of the through hole. When the pressure head 8 is stuck, the device becomes a rigid structure and does not have a buffering effect. The skewed pressure head 8 will not contact the product well, thereby affecting the test effect
[0021] As shown in Figure 2 and Figure 3 In this embodiment, the top of the T-shaped mounting block 6 is provided with a cover plate 9, and the cover plate 9 is in top support cooperation with the top of the flat spring. The cover plate 9 is used to install and limit the flat spring.
[0022] As shown in Figure 1 , Figure 2 In this embodiment, the number of groups of the stepping motor 2 is four, and the four groups of the stepping motor 2 are arranged side by side on the panel of the mounting plate 1.
[0023] As shown in Figure 1 In this embodiment, the elastic force control device based on the stepping motor further comprises a rack 10 and a sliding frame 11, the top of the rack 10 is provided with two groups of symmetrically arranged linear guides 12, the linear guides 12 are slidingly provided with sliding blocks 13, the sliding frame 11 is arranged on the top of the sliding block 13, the mounting plate 1 is arranged on the sliding frame 11, the sliding frame 11 is connected with the action end of the external linear module, and a profiling groove 14 adapted to the product is formed between the two groups of linear guides 12. The profiling groove 14 is used to install the product, and the linear guide 12 plays a guiding and supporting role for the movement of the sliding block 13.
[0024] In this embodiment, the end of the linear guide 12 is provided with a buffer 15, and the buffer 15 is in limiting cooperation with the sliding block 13, so as to limit the movement stroke of the sliding block 13, and avoid overdrive of the sliding block 13.
[0025] As Figure 1 shown, in this embodiment, the profiling groove 14 is provided with a positioning pin 16, which is positioned in cooperation with the product, thereby avoiding displacement of the product.
[0026] In this embodiment, the application can control the downstroke of the stepper motor 2, prevent overpressure and adjust the device control force stability time, and use the stepper motor 2 to control the force. Since the stepper motor 2 has no feedback system in the working process, it needs to feedback the signal to the stepper motor 2 through the pressure sensor 5. In this movement process, since the time required for force stability is required, if the speed of the stepper motor 2 is too fast, the feedback of the pressure sensor 5 is not enough, and the overshoot has occurred, which damages the product. If the speed of the stepper motor 2 is too slow, the target of completing the control force within the required time cannot be reached. The application adopts a three-stage speed regulation method to control the force of the stepper motor 2: the first stage quickly approaches the product test near point, and the near point approaches the product surface by 2mm; the second stage is a 1mm deceleration stage, and the stepper motor 2 decelerates; the third stage accurately finds the target load at a speed of 0.05mm / s. In order to prevent the stepper motor 2 from not decelerating enough in the second deceleration stage, resulting in overshoot contact with the product, thereby making the control force not accurate, the elastic buffer structure is increased, the pressure head 8 is used, the compression spring 7 with low elastic coefficient is used, and the stepper motor 2 is ensured to accurately find the target load without overshooting the target load under a certain overshoot amount.
Claims
1. A step motor based elastic force control device, comprising a mounting plate (1) provided with a plurality of step motors (2) arranged in a vertical direction, characterized in that: The output shaft of the stepping motor (2) is drivenly connected with a lead screw (3), the lead screw (3) is slidably provided with an L-shaped mounting block (4), the bottom of the L-shaped mounting block (4) is provided with a pressure sensor (5), the bottom of the pressure sensor (5) is connected with a T-shaped mounting block (6), the T-shaped mounting block (6) is provided with a through hole, the through hole is provided with a compression spring (7) and a pressure head (8), the T-shaped mounting block (6) is top-pressed with the pressure head (8) through the compression spring (7), and the pressure head (8) is top-pressed with a product.
2. The elastic force control device based on a stepper motor according to claim 1, characterized in that: The compression spring (7) is a flat bottom spring, the pressure head (8) is a T-shaped cylindrical head, the diameter of the upper end of the T-shaped cylindrical head is greater than the diameter of the lower end of the T-shaped cylindrical head, the upper hole diameter of the through hole is greater than the lower hole diameter of the through hole, the diameter of the upper end of the T-shaped cylindrical head is matched with the upper hole diameter of the through hole, the diameter of the lower end of the T-shaped cylindrical head is matched with the lower hole diameter of the through hole, and the bottom of the flat bottom spring is flush with the top of the T-shaped cylindrical head.
3. The elastic force control device based on a stepper motor according to claim 2, characterized in that: The top of the T-shaped mounting block (6) is provided with a cover plate (9), and the cover plate (9) is top-braced with the top of the flat bottom spring.
4. The elastic force control device based on a stepper motor according to claim 1, characterized in that: The number of groups of the stepping motor (2) is four, and four groups of the stepping motor (2) are arranged side by side on the panel of the mounting plate (1).
5. The elastic force control device based on a stepper motor according to claim 1, characterized in that: The elastic force control device based on the stepping motor further comprises a rack (10) and a sliding frame (11), the top of the rack (10) is provided with two groups of symmetrical linear guides (12), the linear guides (12) are slidably provided with sliding blocks (13), the sliding frame (11) is arranged on the top of the sliding blocks (13), the mounting plate (1) is arranged on the sliding frame (11), the sliding frame (11) is connected with the action end of an external linear module, and a profiling groove (14) matched with a product is arranged between the two groups of linear guides (12).
6. The elastic force control device based on a stepper motor according to claim 5, characterized in that: The end of the linear guide (12) is provided with a buffer (15), and the buffer (15) is limitingly matched with the sliding block (13).
7. The elastic force control device based on a stepper motor according to claim 5, characterized in that: The profiling groove (14) is provided with a positioning pin (16), and the positioning pin (16) is positionally matched with a product.