An eccentric shaft system with angular position self-detection and automatic calibration functions

Abstract

The present invention provides an eccentric shaft system with angle position self-checking and automatic calibration functions, which relates to the technical field of eccentric shaft position calibration devices, including a base, an eccentric shaft mounted on the base, a motor mounted on one end of the eccentric shaft, a test head fixed on the eccentric shaft, a force sensor connected to the test head and fixed on the base, a spring sleeved on the force sensor and located between the test head and the force sensor, an encoder installed in the motor, and a control board connected to the force sensor and the encoder; the force sensor sends the tested spring force data converted from the offset of the eccentric shaft to the control board for processing, and the encoder reads the angle position of the eccentric shaft and sends the angle position information to the control board. The present invention can automatically measure the eccentric position of the eccentric shaft and calibrate the eccentric shaft to the required angle position; it can automatically complete the self-check of the angle position of the eccentric shaft as needed to find errors in time.

Description

Technical Field

[0001] The invention relates to an eccentric shaft position calibration device, in particular to an eccentric shaft system with angle position self-checking and automatic calibration functions, belonging to the technical field. Background Art

[0002] In some high-precision moving parts containing eccentric shafts, the angular position of the eccentric shaft needs to be accurately located. However, due to processing and installation errors or long-term movement that causes slight position deviations, the eccentric shaft often needs to be calibrated for angle position. Many existing eccentric shaft systems need to install and disassemble related detection tools or go to a dedicated detection platform for detection each time they are detected or calibrated. Automatic detection and calibration cannot be achieved, nor can self-checking of the angle position be achieved. The detection and calibration process is relatively complicated and consumes a lot of manpower and material resources.

[0003] Based on this, this application is made. Summary of the invention

[0004] In order to solve the above defects in the prior art, the present invention provides an eccentric shaft system with angular position self-detection and automatic calibration functions.

[0005] In order to achieve the above object, the technical solution adopted by the present invention is as follows:

[0006] An eccentric shaft system with angular position self-checking and automatic calibration functions comprises a base, an eccentric shaft mounted on the base, and a motor mounted on one end of the eccentric shaft, and also comprises a test head fixed on the eccentric shaft, a force sensor connected to the test head and fixed on the base, a spring sleeved on the force sensor and located between the test head and the force sensor, an encoder mounted in the motor, and a control board communicatively connected to the force sensor and the encoder; the force sensor sends the tested spring force data converted from the offset of the eccentric shaft to the control board for processing, and at the same time, the encoder reads the angular position of the eccentric shaft and sends the angular position information to the control board.

[0007] Preferably, the specific steps of the angle position self-check are: by using the maximum / minimum force value obtained by the force sensor at the extreme eccentric position of the original calibrated eccentric shaft as the calibration value and comparing it with the maximum / minimum force value obtained by the force sensor at the extreme eccentric position of the current eccentric shaft, it is determined whether the angle position of the current eccentric shaft relative to the encoder has changed, thereby realizing angle position self-check.

[0008] Preferably, the specific steps of the angle position self-check are: by comparing the relative angle deviation between the original calibration encoder zero position and the eccentric position of the eccentric shaft with the relative angle deviation between the current encoder zero position and the eccentric position of the eccentric shaft, it is determined whether the current eccentric shaft angle position relative to the encoder has changed, thereby realizing angle position self-check;

[0009] Preferably, the automatic calibration includes coarse adjustment and fine adjustment, and the specific steps of coarse adjustment are: obtaining the calibration value through comparison, the control board drives the motor to rotate, and the torque value and the corresponding angle value of the force sensor during one movement are recorded in real time, and stored in the memory. After the movement is completed, the angle value corresponding to the maximum torque value is found in the corresponding memory; the angle corresponding to the maximum torque value is unique, so the maximum value can be set to the rotation zero position.

[0010] The specific steps of fine adjustment are: find the angle value corresponding to the maximum torque value at a slower speed within ±1° of the angle value found during the rough adjustment process to improve the torque detection accuracy.

[0011] Preferably, the test head is a planar test head.

[0012] Working principle of the present invention: The present invention fixes the force sensor to the eccentric shaft mechanism, drives the eccentric shaft to rotate with a motor, converts the change of the relative position of the eccentric shaft into the force change of the force sensor, and then processes the relevant force change signal through the electronic circuit. When the received force is maximum or minimum, the current eccentric shaft is at the extreme eccentric position. At this time, the current angular position of the encoder is read, and the relative angular deviation between the encoder zero position and the eccentric position of the eccentric shaft can be calculated, so that the eccentric shaft can be calibrated to the required angular position through motor control.

[0013] At the same time, in daily use, the eccentric shaft is rotated to the previously calibrated extreme eccentric position by the motor, and the force value of the force sensor is read at this time, and then compared with the maximum or minimum force received by the force sensor when the eccentric shaft rotates a full circle (or the relative angle deviation between the encoder and the eccentric position of the eccentric shaft is calculated as described above, and this deviation value is compared with the previously recorded deviation value), so as to determine whether the current angular position of the eccentric shaft relative to the encoder has changed. If there is a change, calibration is required, and if there is no change, it can continue to be used normally.

[0014] The present invention can realize automatic measurement and calibration of the angular position of the eccentric shaft, and can also automatically complete self-checking of the angular position, and can calibrate in time when an error occurs. In addition, the solution can be directly integrated into the system to avoid waste of manpower and material resources caused by repeated disassembly.

[0015] The present invention can achieve the following technical effects:

[0016] (1) The present invention can automatically measure the eccentric position of the eccentric shaft and calibrate the eccentric shaft to a required angular position.

[0017] (2) The present invention can automatically complete self-checking of the angular position of the eccentric shaft as required, and detect errors in a timely manner.

[0018] (3) The present invention has a simple structure, occupies a small space, and can be directly integrated into the eccentric shaft system. There is no need to repeatedly disassemble and assemble related tooling for each inspection or calibration. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a schematic diagram of the overall structure of an eccentric shaft system with angle position self-detection and automatic calibration functions according to this embodiment;

[0020] Figure 2 This is a structural schematic diagram of an eccentric shaft system force sensor with angle position self-checking and automatic calibration functions for testing an eccentric shaft in this embodiment;

[0021] Figure 3 This is an overall module block diagram of an eccentric shaft system with angle position self-detection and automatic calibration functions according to the present embodiment;

[0022] Figure 4 This is a control flow chart of an eccentric shaft system with angle position self-checking and automatic calibration functions according to the present embodiment;

[0023] Figure 5 This is a rough adjustment flow chart of an eccentric shaft system with angle position self-checking and automatic calibration functions according to the present embodiment;

[0024] Figure 6 A fine adjustment flow chart of the eccentric shaft system having an angle position self-checking and automatic calibration function in this embodiment;

[0025] Figure 7 This is a circuit module control block diagram of an eccentric shaft system with angle position self-detection and automatic calibration functions according to this embodiment.

[0026] Labeling description: test head 1, spring 2, force sensor 3, fixing block 4, fastening screw 5, communication cable 1 6, control board 7, communication cable 2 8, encoder 9, stepper motor 10, coupling 11, eccentric shaft 12, base 13. DETAILED DESCRIPTION

[0027] In order to make the technical means of the present invention and the technical effects that can be achieved by it more clearly and completely disclosed, the following embodiments are provided and described in detail as follows in conjunction with the accompanying drawings:

[0028] like Figure 1 and Figure 2As shown, an eccentric shaft 12 system with angle position self-checking and automatic calibration functions of this embodiment includes a base 13, an eccentric shaft 12 installed on the base 13, and a motor 10 installed on one end of the eccentric shaft 12, and also includes a test head 1 fixed on the eccentric shaft 12, a force sensor 3 connected to the test head 1 and fixed on the base 13, a spring 2 sleeved on the force sensor 3 and located between the test head 1 and the force sensor 3, an encoder 9 installed in the motor 10, and a control board 7 communicatively connected to the force sensor 3 and the encoder 9 (through a communication cable); the force sensor 3 sends the tested spring 2 force data converted from the offset of the eccentric shaft 12 to the control board 7 for processing, and at the same time, the encoder 9 reads the angular position of the eccentric shaft 12 and sends the angular position information to the control board 7.

[0029] The force sensor 3 is fixed on the base 13 via a fixing block 4 and a fastening screw 5 .

[0030] The motor 10 and the eccentric shaft 12 are connected via a coupling 11 .

[0031] The functions of the various components in this embodiment are described in detail below:

[0032] Test head 1: When the eccentric shaft 12 rotates, the test head 1 contacts the eccentric shaft 12 and transmits the offset of the eccentric shaft 12 to the test head 1 in real time. In this embodiment, the test head 1 adopts a flat test head 1 to avoid the center plane of the test head 1 and the rotation center of the eccentric shaft 12 being different planes due to processing and assembly errors, thereby affecting the measurement of the eccentric position of the eccentric shaft 12;

[0033] The spring 2 is used to convert the movement of the test head 1 into a change in the force of the spring 2 and transmit the force to the force sensor 3;

[0034] The force sensor 3 is used to measure the force exerted by the spring 2 on it in real time;

[0035] The communication cable is used for communication and data transmission between the force sensor 3 and the control board 7;

[0036] The control board 7 is used to process the relevant data of the force sensor 3 and the encoder 9;

[0037] The communication cable is used for communication and data transmission between the encoder 9 and the control board 7;

[0038] The encoder 9 is used to read the current angular position of the eccentric shaft 12, on which a zero position can be set. The extreme eccentric position of the eccentric shaft 12 and the zero position of the encoder 9 have a relative deflection angle;

[0039] The motor 10 is used to drive the eccentric shaft 12 to rotate;

[0040] The coupling 11 is used to connect the motor 10 and the eccentric shaft 12;

[0041] The eccentric shaft 12 is a measurement object whose angle position needs to be calibrated;

[0042] The base 13 is used to fix the eccentric shaft 12 and related test components.

[0043] Self-check process: In daily use, the eccentric shaft 12 is rotated to the previously calibrated extreme eccentric position by the motor 10, and the force value of the force sensor 3 is read at this time, and then compared with the maximum or minimum force received by the force sensor 3 when the eccentric shaft 12 rotates a full circle (or the relative angle deviation between the encoder 9 and the eccentric position of the eccentric shaft 12 is calculated as described above, and this deviation value is compared with the previously recorded deviation value), so as to determine whether the current angular position of the eccentric shaft 12 relative to the encoder 9 has changed. If there is a change, calibration is required. If there is no change, it can continue to be used normally. The detailed process of self-check is consistent with the calibration process, which mainly determines whether the position of the current shaft or encoder 9 is loose.

[0044] Automatic calibration process, such as Figure 3 As shown, the eccentric shaft 12 is driven to rotate by the motor 10. The change in the angular position of the eccentric shaft 12 causes the position of the test head 1 to change, and at the same time, the compression or extension of the spring 2 causes the change in the force of the spring 2. The spring 2 transmits the force to the force sensor 3, which senses the change in force in real time and sends the force information to the control board 7 through the communication cable. When the force received by the control board 7 is the largest, the current eccentric shaft 12 is at the extreme eccentric position. At this time, the current angular position of the encoder 9 is read to calculate the relative angular deviation between the zero position of the encoder 9 and the extreme eccentric position of the eccentric shaft 12, and this calibration value is saved in a Flash memory that is not lost when the power is off, so that the eccentric shaft 12 can be calibrated to the required angular position by the control of the motor 10.

[0045] like Figure 4 As shown, the entire calibration process is generally divided into two steps: coarse adjustment process and fine adjustment process.

[0046] like Figure 5 As shown, during the coarse adjustment process, the control board 7 drives the stepper motor 10 to rotate one circle, and records the torque value and the corresponding angle value of the force sensor 3 during one circle of movement in real time, and stores them in the memory. After the movement is completed, the angle value corresponding to the maximum torque value is found in the corresponding memory as the calibration value.

[0047] like Figure 6During the fine-tuning process shown, the control board 7 drives the stepper motor 10 to rotate ten circles, and records the torque value and the corresponding angle value of the force sensor 3 during the ten circles of movement in real time, and stores them in the memory. After the movement is completed, the angle value corresponding to the maximum torque value of each circle is found in the corresponding memory, and the average value is taken as the calibration value.

[0048] The above content is a further detailed description of the technical solution provided in combination with the preferred implementation mode of the present invention. It cannot be determined that the specific implementation of the present invention is limited to the above descriptions. For ordinary technicians in the technical field to which the present invention belongs, several simple deductions or substitutions can be made without departing from the concept of the present invention, which should be regarded as belonging to the protection scope of the present invention.

Claims

1. An eccentric shaft system with angle position self-checking and automatic calibration functions, comprising a base, an eccentric shaft mounted on the base, and a motor mounted on one end of the eccentric shaft, characterized in that: The invention also includes a test head fixed on the eccentric shaft, a force sensor connected to the test head and fixed on the base, a spring sleeved on the force sensor and located between the test head and the force sensor, an encoder installed in the motor, and a control board connected to the force sensor and the encoder in communication; the force sensor sends the tested spring force data converted from the offset of the eccentric shaft to the control board for processing, and at the same time, the encoder reads the angular position of the eccentric shaft and sends the angular position information to the control board; the specific steps of the angle position self-check are: by comparing the maximum / minimum force value obtained by the force sensor at the extreme eccentric position of the original calibration eccentric shaft as a calibration value with the maximum / minimum force value obtained by the force sensor at the extreme eccentric position of the current eccentric shaft, judging whether the angle position of the current eccentric shaft relative to the encoder has changed, and realizing the angle position self-check; or by comparing the relative angle deviation between the zero position of the original calibration encoder and the eccentric position of the eccentric shaft with the relative angle deviation between the zero position of the current encoder and the eccentric position of the eccentric shaft, judging whether the angle position of the current eccentric shaft relative to the encoder has changed, and realizing the angle position self-check.

2. An eccentric shaft system with angle position self-detection and automatic calibration functions as claimed in claim 1, characterized in that: The automatic calibration includes rough adjustment and fine adjustment. The specific steps of rough adjustment are: obtain the calibration value through comparison, control the board to drive the motor to rotate, record the torque value and the corresponding angle value of the force sensor during one cycle of movement in real time, and store them in the memory. After the movement is completed, find the angle value corresponding to the maximum torque value in the corresponding memory; The specific steps of fine adjustment are: find the angle value corresponding to the maximum torque value at a slower speed within ±1° of the angle value found during the coarse adjustment.

3. The eccentric shaft system with angle position self-detection and automatic calibration functions as claimed in claim 1, characterized in that: The test head is a flat test head.

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