Telescopic length measuring sensor zero point calibration system, telescopic arm and engineering machine

Abstract

This invention discloses a zero-point calibration system for a telescopic length measuring sensor, a telescopic boom, and related engineering machinery. The zero-point calibration system includes a calibration detection module, a calibration execution module, and a telescopic length measuring sensor. The calibration detection module detects whether the telescopic cylinder has retracted to the zero position according to a preset detection time in automatic mode, and sends a calibration enable signal to the calibration execution module when the detection result is yes. The calibration execution module sends a calibration command to the telescopic length measuring sensor upon receiving the calibration enable signal. Upon receiving the calibration command, the telescopic length measuring sensor sets its internal encoder to zero, thus achieving zero-point calibration. This invention enables the sensor to measure accurate true values ​​without additional processing of the raw values.

Description

Technical Field

[0001] This invention relates to zero-point calibration technology, and more particularly to a zero-point calibration system for a telescopic length measuring sensor, a telescopic arm, and engineering machinery. Background Technology

[0002] When a single-cylinder pin-type crane moves its telescopic boom, a telescopic length measuring sensor is needed to detect the position and state of the hydraulic cylinder. Based on the extended length of the cylinder, the speed and direction of the cylinder's movement are controlled. For example... Figure 1 As shown, the telescopic length measuring sensor includes a drum 11 and a measuring cable 12. Normally, the drum 11 is fixed stationary. One end of the measuring cable 12 is fixed to the drum 11 and connected to an internal brush. The other end of the measuring cable 12 moves with a hydraulic cylinder, similar to a steel measuring tape. The telescopic length measuring sensor uses a spiral spring as power to wind the cable. When the measuring cable 12 is pulled out, the spiral spring tightens and stores energy. When the external force is removed, the spring releases energy, and the drum 11 automatically winds up the measuring cable 12. The telescopic length measuring sensor converts the number of rotations of the encoder inside the drum 11 to the length of the measuring cable 12 pulled out, providing real-time length measurement data.

[0003] However, due to initial connection deviations in the telescopic length measuring sensor cable, dimensional deviations in the extender arm structure, or cable elongation caused by prolonged stretching, the internal encoder zero-point position may shift when the telescopic cylinder is in the zero-position state, resulting in zero-point drift. This further leads to inaccurate length measuring data from the telescopic cylinder, causing the telescopic system to operate unevenly or unsuccessfully. Therefore, it is necessary to calibrate the zero point of the telescopic length measuring sensor.

[0004] Patent application number 201510332138.6 discloses a method and system for calibrating the cylinder length line of a telescopic boom, and a crane. It determines the cylinder length line calibration system based on the readings and actual values ​​of displacement sensors at at least two sets of telescopic booms in their respective positions, recalculating the original sensor values ​​into the required cylinder length line value. Patent application number 200810111016.4 discloses a telescopic boom in-situ signal generator, a length correction system, and engineering machinery. It installs detection elements on the basic boom and second-section boom to achieve in-situ state detection, and corrects the measured length based on the readings of the length measuring sensors in the in-situ state. These prior art technologies all calibrate the measured values ​​through subsequent data processing based on the original measured values, without changing the original measured values. They cannot calibrate the sensor zero point and cannot solve the problem of inaccurate original measured values. Summary of the Invention

[0005] Purpose of the invention: To address the technical shortcomings of existing telescopic length measuring sensors in terms of zero-point drift, this invention provides a telescopic length measuring sensor zero-point calibration system, a telescopic arm with the zero-point calibration system, and engineering machinery with the telescopic arm or zero-point calibration system, ensuring that the original values ​​measured by the sensor are accurate true values ​​without additional processing.

[0006] Technical solution: This invention provides a zero-point calibration system for a telescopic length measuring sensor, comprising:

[0007] The calibration detection module is used to detect whether the telescopic cylinder has retracted to the zero position according to a preset detection time in automatic mode, and to send a calibration enable signal to the calibration execution module when the detection result is yes.

[0008] The calibration execution module is used to send calibration commands to the telescopic length measuring sensor when a calibration enable signal is received.

[0009] The telescopic length measuring sensor is used to zero out the internal encoder after receiving a calibration command, thereby achieving zero-point calibration.

[0010] Furthermore, the system also includes:

[0011] The calibration switch is used to send a calibration enable signal to the calibration execution module when pressed by the user in manual mode.

[0012] Furthermore, the system also includes:

[0013] The display shows the real-time calibration status and measurement results of the telescopic length measuring sensor.

[0014] Furthermore, the zero-point calibration detection module specifically includes:

[0015] The detection time setting unit is used to set the detection time in automatic mode;

[0016] The cylinder pin status detection unit is used to detect whether the cylinder pin is inserted into the cylinder pin hole of the second arm.

[0017] The arm pin status detection unit is used to detect whether the arm pin of the second arm is inserted into the 0% arm pin hole of the basic arm;

[0018] The telescopic cylinder retraction pressure detection unit is used to detect whether the retraction pressure of the telescopic cylinder is greater than the set value P;

[0019] The signal generation unit is used to determine that the telescopic arm has retracted to the zero position when the detection results of the cylinder pin state detection unit, the arm pin state detection unit, and the telescopic cylinder retraction pressure detection unit are all positive, and to send a calibration enable signal to the calibration execution module.

[0020] Furthermore, the telescopic length measuring sensor is also used to send a calibration success signal to the calibration execution module after zero-point calibration. The calibration execution module is also used to send a calibration command again if it does not receive a calibration success signal within a preset time.

[0021] Furthermore, the calibration execution module is also used to control the sending time and number of calibration instructions according to a preset time.

[0022] Furthermore, the calibration switch is a physical switch or a virtual switch on the display.

[0023] The present invention also provides a telescopic arm having the above-mentioned telescopic length measuring sensor zero-point calibration system.

[0024] The present invention also provides an engineering machine having the above-mentioned telescopic arm.

[0025] The present invention also provides another type of engineering machinery, which has the above-mentioned telescopic length measuring sensor zero-point calibration system.

[0026] Beneficial effects: Compared with the prior art, the significant advantages of this invention are: This invention enables the raw value measured by the telescopic length measuring sensor to be an accurate true value without additional processing, which can solve the problem that the inaccurate measurement of the cylinder length caused by the zero drift of the telescopic length measuring sensor affects the telescopic movement of the crane. In automatic mode, zero-point calibration can be automatically achieved, improving the reliability of product operation. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of the telescopic length measuring sensor.

[0028] Figure 2 This is a block diagram of the zero-point calibration system for the telescopic length measuring sensor provided by the present invention;

[0029] Figure 3 This is a schematic diagram of the telescopic hydraulic cylinder in its zero-position state;

[0030] Figure 4 This is a flowchart illustrating the manual mode of the zero-point calibration system for the telescopic length measuring sensor of the present invention.

[0031] Figure 5 This is a flowchart illustrating the manual mode of the zero-point calibration system for the telescopic length measuring sensor of the present invention. Detailed Implementation

[0032] This embodiment provides a zero-point calibration system for a telescopic length measuring sensor, such as... Figure 2As shown, the system includes a calibration detection module, a calibration switch, a calibration execution module, a telescopic length measuring sensor, and a display. The calibration system in this embodiment has both manual and automatic modes. The switches for manual and automatic modes can be physical switches or virtual switches on the display.

[0033] The calibration detection module is used to check whether the telescopic cylinder has retracted to the zero position according to a preset detection time when the user selects the automatic mode, and sends a calibration enable signal to the calibration execution module when the detection result is yes. Figure 3 As shown, the zero-position state of the telescopic cylinder 13 is as follows: the cylinder pin 14 of the telescopic cylinder is inserted into the cylinder pin hole 16 of the second-section arm 15, and the arm pin 17 of the second-section arm is inserted into the 0% arm pin hole 19 of the basic arm 18. The telescopic length measuring sensor is set to zero at this point, allowing for real-time measurement of the extended length of the telescopic cylinder with millimeter-level accuracy. Therefore, the calibration detection module includes a detection time setting unit, a cylinder pin status detection unit, an arm pin status detection unit, a telescopic cylinder retraction pressure detection unit, and a signal generation unit. The detection time setting unit is used to set the detection time in automatic mode. For example, it can be detected every certain period of time (a few minutes or tens of minutes, etc.), or it can be executed once per power-on cycle or once per other cycle. The cylinder pin status detection unit detects whether the cylinder pin is inserted into the cylinder pin hole of the second-section arm; the arm pin status detection unit detects whether the arm pin of the second-section arm is inserted into the 0% arm pin hole of the basic arm; the telescopic cylinder retraction pressure detection unit detects whether the retraction pressure of the telescopic cylinder is greater than the set value P; the signal generation unit determines that the telescopic arm has retracted to the zero position when the detection results of the cylinder pin status detection unit, the arm pin status detection unit, and the telescopic cylinder retraction pressure detection unit are all positive, and sends a calibration enable signal to the calibration execution module. The telescopic cylinder retraction pressure detection unit can reduce the influence of the cylinder arm pin hole clearance on the calibration accuracy. When the telescopic cylinder retraction pressure is greater than the set value P, it is considered that the cylinder drives the telescopic arm to retract to the bottom with no mechanical clearance.

[0034] The calibration switch is used to send a calibration enable signal to the calibration execution module when pressed by the user in manual mode. It can be a physical switch or a virtual switch on the display.

[0035] The calibration execution module is used to send a calibration command to the telescopic length measuring sensor when a calibration enable signal is received, and to send the calibration command again if a calibration success signal is not received within a preset time. It is also used to control the sending time and number of calibration commands according to a preset time. For example, it can be set to perform calibration once every time the calibration detection module sends a calibration enable signal, or to perform calibration once every power-on cycle, or to perform calibration once within other specified cycles.

[0036] The telescopic length measuring sensor is used to zero out the internal encoder after receiving the calibration command, thereby achieving zero-point calibration, and to send a calibration success signal to the calibration execution module after zero-point calibration.

[0037] The display shows the real-time calibration status and measurement results of the telescopic length measuring sensor. It can also be used to display the manual mode, automatic mode, and virtual switch of the calibration switch.

[0038] The calibration process in this embodiment is as follows:

[0039] 1) Manual mode: such as Figure 4 As shown, when the calibration switch is manually pressed, the calibration execution module receives the calibration enable signal and sends a calibration command to the telescopic length measuring sensor according to a predetermined program. It then waits for the sensor to reply with a calibration success signal. If no calibration success signal is received within the set time, the calibration command is sent again. The display shows the current sensor measurement value and calibration status in real time.

[0040] 2) Automatic mode: such as Figure 5 As shown, the calibration detection module monitors the telescopic cylinder status in real time. When the cylinder pin is inserted into the second-section arm's cylinder pin hole, and the second-section arm's arm pin is inserted into the 0% arm pin hole of the basic arm, and the telescopic cylinder's retraction pressure is greater than the set value P, it automatically sends a calibration enable signal to the calibration execution module to perform zero-point calibration. After receiving the calibration command from the calibration detection module, the calibration execution module executes the same calibration process as in manual mode until calibration is successful. The display shows the current sensor measurement values ​​and calibration status in real time.

[0041] This embodiment also provides a telescopic arm, which, in addition to other basic settings, also has the above-mentioned telescopic length measuring sensor zero-point calibration system.

[0042] This embodiment also provides an engineering machine, which, in addition to other basic settings, also has the aforementioned telescopic boom. This engineering machine can be a crane or other machinery.

[0043] This embodiment also provides an engineering machine, which, in addition to other basic settings, also has the above-mentioned telescopic length measuring sensor zero-point calibration system. The engineering machine can be a crane or other machinery.

[0044] The above-disclosed embodiments are merely preferred embodiments of the present invention and should not be construed as limiting the scope of the present invention. Therefore, any equivalent variations made in accordance with the claims of the present invention are still within the scope of the present invention.

Claims

1. A zero-point calibration system for a telescopic length measuring sensor, characterized in that... include: The calibration detection module is used to detect whether the telescopic cylinder has retracted to the zero position according to a preset detection time in automatic mode, and to send a calibration enable signal to the calibration execution module when the detection result is yes. The calibration execution module is used to send calibration commands to the telescopic length measuring sensor when a calibration enable signal is received. The telescopic length measuring sensor is used to zero out the internal encoder after receiving a calibration command, thereby achieving zero-point calibration. The zero-point calibration detection module specifically includes: The detection time setting unit is used to set the detection time in automatic mode; The cylinder pin status detection unit is used to detect whether the cylinder pin is inserted into the cylinder pin hole of the second arm. The arm pin status detection unit is used to detect whether the arm pin of the second arm is inserted into the 0% arm pin hole of the basic arm; The telescopic cylinder retraction pressure detection unit is used to detect whether the retraction pressure of the telescopic cylinder is greater than the set value P; The signal generation unit is used to determine that the telescopic cylinder has retracted to the zero position when the detection results of the cylinder pin state detection unit, the arm pin state detection unit, and the telescopic cylinder retraction pressure detection unit are all positive, and to send a calibration enable signal to the calibration execution module.

2. The zero-point calibration system for the telescopic length measuring sensor according to claim 1, characterized in that... Also includes: The calibration switch is used to send a calibration enable signal to the calibration execution module when pressed by the user in manual mode.

3. The zero-point calibration system for the telescopic length measuring sensor according to claim 1, characterized in that... Also includes: The display shows the real-time calibration status and measurement results of the telescopic length measuring sensor.

4. The zero-point calibration system for the telescopic length measuring sensor according to claim 1, characterized in that: The telescopic length measuring sensor is also used to send a calibration success signal to the calibration execution module after zero-point calibration. The calibration execution module is also used to send a calibration command again if it does not receive a calibration success signal within a preset time.

5. The zero-point calibration system for the telescopic length measuring sensor according to claim 1, characterized in that: The calibration execution module is also used to control the sending time and number of calibration instructions according to a preset time.

6. The zero-point calibration system for the telescopic length measuring sensor according to claim 2, characterized in that: The calibration switch is a physical switch or a virtual switch on the display.

7. A telescopic boom, characterized in that: The telescopic arm has a telescopic length measuring sensor zero-point calibration system as described in any one of claims 1-6.

8. An engineering machinery, characterized in that: The engineering machinery has the telescopic boom as described in claim 7.

9. An engineering machinery, characterized in that: The engineering machinery has a zero-point calibration system for a telescopic length measuring sensor as described in any one of claims 1-6.

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