A pull cord displacement sensor with dual encoder signal redundancy

Abstract

This application provides a draw-rope displacement sensor with dual encoder signal redundancy, including a dual encoder module containing the sensor, and a mechanical draw-rope assembly including a draw-rope box and a spring rewinding device; the draw-rope box includes a draw-rope, one end of which is fixed to the object being measured, and the other end is wound around a hub, the hub being provided with a rotating shaft coaxially connected to the hub, and a gear is provided on the rotating shaft; the dual encoder module includes a main encoder and a redundant encoder, the main encoder and the redundant encoder being respectively geared to the rotating shaft, and synchronously acquiring the rotation signal of the hub through the gear transmission; a main control unit, electrically connected to the main encoder and the redundant encoder respectively, is used to receive the rotation signals of the main encoder and the redundant encoder in real time, thereby obtaining the distance values ​​measured by the main encoder and the redundant encoder respectively.

Description

Technical Field

[0001] This application relates to the field of displacement measurement technology, and in particular to a rope displacement sensor with dual encoder signal redundancy. Background Technology

[0002] In the field of displacement measurement technology, linear displacement sensors are widely used and are currently mainly divided into two categories: contact and non-contact. Non-contact sensors, represented by radar and lasers, are highly susceptible to interference from external environmental factors during practical use. For example, in environments with high humidity or dust levels, or when physical obstructions are present, measurement results may become inaccurate, leading to a significant decrease in measurement accuracy. Contact sensors, primarily based on static magnetic sensors, have stringent requirements for the mechanical installation of the equipment. If the equipment is subjected to vibration or impact, the sensor may deform or even be damaged. Utility Model Content

[0003] To address the aforementioned issues, this application provides a draw-rope displacement sensor with dual encoder signal redundancy, comprising a dual encoder module containing a sensor, and a mechanical draw-rope assembly containing a draw-rope box and a spring rewinding device. The draw-rope box includes a draw-rope, one end of which is fixed to a moving object, and the other end is wound around a hub. The hub is provided with a rotating shaft coaxially connected to the hub, and a gear is provided on the rotating shaft.

[0004] The dual encoder module includes a main encoder and a redundant encoder. The main encoder and the redundant encoder are respectively driven by gears to the rotating shaft, and the rotation signal of the hub is collected synchronously through the gear transmission.

[0005] The main control unit is electrically connected to the main encoder and the redundant encoder respectively, and is used to receive the rotation signals of the main encoder and the redundant encoder in real time, so as to obtain the distance values ​​measured by the main encoder and the redundant encoder respectively.

[0006] Optionally, the input end of the gear drive is rigidly connected to the rotating shaft of the hub, and the output end drives the main encoder and the redundant encoder respectively, ensuring that the two encoders rotate synchronously and output independent signals.

[0007] Optionally, the hub includes a lead screw cable laying mechanism coaxially connected to the hub, wherein the lead screw cable laying mechanism realizes the active cable laying of the pull rope through the cooperation of the lead screw and the nut;

[0008] The rotating shaft of the hub directly drives the lead screw, and the lead screw controls the orderly winding and unwinding of the rope through the linear movement of the nut, avoiding cable overlap or jamming.

[0009] Optionally, the pull rope displacement sensor further includes a universal wheel guide mechanism, which is located at the pull rope outlet to support the movement trajectory of the pull rope;

[0010] The lead screw limiting device includes at least two microswitches or photoelectric switches disposed on the pull rope path to detect the maximum / minimum displacement and motion state of the pull rope.

[0011] Optionally, the omnidirectional wheel guide mechanism includes a guide bracket and at least two omnidirectional wheels embedded in the guide bracket, wherein the at least two omnidirectional wheels form a V-groove in the guide bracket, so that the pull rope passes through the V-groove.

[0012] Optionally, the signal output terminal of the micro switch or photoelectric switch is connected to the main control unit via a wire, and the main control unit determines whether the pull rope exceeds the safe travel based on the limit signal.

[0013] Optionally, the main control unit is configured as follows:

[0014] By comparing the output signals of the main encoder and the redundant encoder, if the difference exceeds a preset threshold, it is determined that there is interference in the signal and the signal path is switched.

[0015] If both signals remain unchanged, it is determined that the pull rope or spring is damaged, and an alarm signal is triggered.

[0016] Optionally, the spring rewinding device includes a spring, one end of which is fixed to the hub and the other end to the pull cable box, for storing energy when the pull cable is pulled out, driving the hub to rotate after the pull cable is released, and automatically returning to its original position around the hub.

[0017] The technical solutions provided in this application embodiment may include the following beneficial effects:

[0018] The present invention provides a rope displacement sensor with dual encoder signal redundancy. It uses a main encoder and a redundant encoder (such as an absolute encoder) to synchronously acquire signals through gear transmission. Combined with the real-time comparison of the two signals by the main control unit, abnormal data can be eliminated and switched in time, which significantly improves anti-interference ability and reliability. It is suitable for complex working conditions such as strong electromagnetic interference and vibration.

[0019] The lead screw cable winding mechanism provided in this application ensures orderly cable winding and unwinding through the active cooperation between the lead screw and the nut, avoiding cable overlap or jamming and extending service life; the universal wheel guide mechanism allows the cable to deflect ±90°, reducing lateral wear and adapting to multi-angle movement requirements.

[0020] By working in conjunction with the main control unit, the displacement status of the pull rope is monitored in real time, achieving dual mechanical and electrical protection; when the signal is abnormal, it automatically switches to the normal path to ensure measurement continuity and reduce maintenance costs. Attached Figure Description

[0021] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0022] Figure 1 This is a schematic diagram of the overall external structure of a drawstring displacement sensor with dual encoder signal redundancy provided in an exemplary embodiment of this application;

[0023] Figure 2 This is a schematic diagram of a portion of the mechanical rope assembly provided in an exemplary embodiment of this application;

[0024] Figure 3 This is a schematic diagram of the mechanical lead screw limiting device provided in an exemplary embodiment of this application;

[0025] Figure 4 This is a schematic diagram of a universal wheel guide mechanism provided in an exemplary embodiment of this application. Detailed Implementation

[0026] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numbers in different drawings denote the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this application. Rather, they are merely examples of apparatuses and methods consistent with some aspects of this application as detailed in the appended claims.

[0027] This application provides a draw-rope displacement sensor with dual encoder signal redundancy, including a dual encoder module containing the sensor, a mechanical draw-rope assembly including a draw-rope box and a spring rewinding device, the draw-rope box including a draw-rope, one end of which is fixed to a moving object, and the other end is wound around a hub, the hub being provided with a rotating shaft coaxially connected to the hub, and a gear being provided on the rotating shaft; the dual encoder module includes a main encoder and a redundant encoder, the main encoder and the redundant encoder being respectively geared to the rotating shaft, synchronously acquiring the rotation signal of the hub through the gear transmission; a main control unit, electrically connected to both the main encoder and the redundant encoder, is used to receive the rotation signals of the main encoder and the redundant encoder in real time, thereby obtaining the distance values ​​measured by the main encoder and the redundant encoder respectively.

[0028] The sensor provided in this application is equipped with a main encoder and a redundant encoder, which are driven by gears. During operation, the main encoder and the redundant encoder separately acquire rotational signals, thereby achieving signal redundancy at the mechanical level. This design provides dual protection for the sensor's signal acquisition, further improving the sensor's reliability.

[0029] For details, please refer to Figures 1 to 4 . Figure 1This is a schematic diagram of the overall external structure of a draw-wire displacement sensor with dual encoder signal redundancy provided in an exemplary embodiment of this application. As shown in the figure, the draw-wire displacement sensor provided in this embodiment includes two encoders: a main encoder and a redundant encoder. The two encoders are driven by a rotating shaft and a gear, respectively, which are coaxially connected to a rotating shaft on a hub. When the draw-wire is pulled, the hub rotates, causing the rotating shaft to rotate. This, in turn, drives the main encoder and the redundant encoder to perform measurements via the gears. The main control unit, electrically connected to both the main encoder and the redundant encoder, receives the rotation signals from each encoder, thus obtaining the distance values ​​measured by the main encoder and the redundant encoder, respectively. Analysis of the two rotation signals determines whether the device is in normal working condition.

[0030] For example, the pull rope is a stainless steel wire rope. One end of the pull rope is fixed to the moving object, and the other end is wound around the hub. The spring rewinding device is linked to the hub and automatically returns to its original position after the pull rope is released, ensuring stable tension of the pull rope. In this embodiment, the mechanical pull rope assembly, including the pull box and the spring rewinding device, is basically the same as the structure of the prior art, and will not be described in detail in this embodiment. The main differences compared with the prior art are as follows:

[0031] For example, please refer to Figure 3 The pull rope displacement sensor provided in this application also includes a lead screw limit device, consisting of at least two micro switches or photoelectric switches, used to detect the maximum / minimum displacement and motion state of the pull rope. For example, the two micro switches or photoelectric switches are located at the outlet of the pull rope box, and the pull rope is equipped with a structural device for triggering the micro switches or photoelectric switches. The signal output terminals of the micro switches or photoelectric switches are connected to the main control unit via wires. The main control unit determines whether the pull rope exceeds its safe travel range based on the limit signal. For instance, when the pull rope moves a certain distance, the triggering device on the pull rope triggers the switch, such as for maximum or minimum limit, other point motion control alarms, etc., to achieve mechanical transmission protection for the equipment.

[0032] In one exemplary embodiment, the pull-cord displacement sensor further includes a universal wheel guide mechanism disposed at the pull-cord outlet to support the movement trajectory of the pull-cord. (See also...) Figure 4 The omnidirectional wheel guide mechanism includes a guide bracket and at least two omnidirectional wheels embedded in the guide bracket. The at least two omnidirectional wheels form V-grooves in the guide bracket, allowing the pull rope to pass through the V-grooves. When the stainless steel pull rope passes through the V-grooves of the omnidirectional wheels, the omnidirectional wheels allow the pull rope to deflect ±90°. Combined with the movable guide rail, it can adapt to multi-angle movement requirements and reduce lateral wear.

[0033] In this embodiment, the hub drive module is closely connected to the cable assembly. The hub is coaxially connected to a lead screw cable winding mechanism, and the lead screw achieves orderly cable winding and unwinding through the linear movement of a nut. For example, the nut moves along the axial direction of the lead screw, driving the cable to wind in an orderly manner, avoiding cable overlap or jamming. Simultaneously, the hub's rotation axis directly drives the input end of the gear drive, and the output end of the gear drive is connected to the main encoder and redundant encoder respectively, ensuring that the two encoders rotate synchronously and output signals independently, achieving redundant signal acquisition.

[0034] In this sensor, the spring rewinding device includes a mainspring, one end of which is fixed to the hub and the other end to the cable box. The mainspring stores energy when the cable is pulled out, and drives the hub to rotate after the cable is released, automatically returning to its original position and winding around the hub. An active cable winding method is employed, using a precision lead screw and nut working together. During the cable winding and unwinding process, the lead screw is driven by a displacement device, synchronously following the extension and retraction of the cable. This active cable winding method ensures neat cable arrangement, effectively avoiding cable overlap or jamming, and greatly improving the sensor's mechanical stability and service life.

[0035] The main control unit is electrically connected to the main encoder, redundant encoder, and lead screw limit device. The main control unit compares the dual signals in real time and eliminates abnormal data. The lead screw limit device includes a microswitch or photoelectric switch mounted on the lead screw, and its signal output is connected to the main control unit via a wire. The main control unit determines whether the pull rope exceeds its safe travel based on the limit signal, achieving dual mechanical and electrical protection. When the signal is abnormal, the main control unit automatically switches to the normal signal path to ensure measurement continuity. It should be noted that this application aims to protect the structural components of a pull rope displacement sensor with dual encoder signal redundancy; the signal processing in the embodiment can be implemented using mature technologies in the field.

[0036] In addition, the pull rope assembly is equipped with an anti-tangling structure located at the end of the lead screw wiring mechanism. The limit boss prevents the pull rope from overlapping, further improving the system reliability.

[0037] In practical applications, when a moving object experiences displacement, the stainless steel pull rope is pulled accordingly, causing the hub to rotate. The hub drive module transmits the rotational motion to the lead screw cable winding mechanism, enabling the orderly winding and unwinding of the pull rope. Simultaneously, the hub rotation drives the main encoder and redundant encoders to rotate synchronously via gear transmission, acquiring displacement signals. After receiving the dual signals, the main control unit performs real-time comparison and processing, eliminating abnormal data, and monitors the pull rope displacement status based on the signal from the lead screw limit device. If an abnormal signal occurs, the main control unit automatically switches to the normal signal path to ensure the accuracy and continuity of the measurement data.

[0038] This rope displacement sensor employs a dual-encoder signal redundancy design, combined with the signal processing logic of the main control unit, significantly improving anti-interference capability and measurement reliability, making it suitable for complex working conditions such as strong electromagnetic interference and vibration. Its screw cable routing mechanism and universal wheel guiding mechanism ensure orderly rope winding and unwinding, reducing wear and extending service life. Simultaneously, the screw limit device works in conjunction with the main control unit to achieve dual protection, effectively reducing maintenance costs.

[0039] Other embodiments of this application will readily occur to those skilled in the art upon consideration of the specification and practice of the utility model disclosed herein. This application is intended to cover any variations, uses, or adaptations of this application that follow the general principles of this application and include common knowledge or customary techniques in the art not disclosed herein. The specification and examples are to be considered illustrative only, and the true scope and spirit of this application are indicated by the following claims.

[0040] It should be understood that this application is not limited to the precise structure described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. The scope of this application is limited only by the appended claims.

Claims

1. A draw-wire displacement sensor with dual encoder signal redundancy, characterized in that, Includes a dual encoder module with sensors, and a mechanical pull rope assembly with a pull box and a spring rewind device; The pull box includes a pull rope, one end of which is fixed to the object being measured, and the other end is wound around a hub. The hub is provided with a rotating shaft coaxially connected to the hub, and a gear is provided on the rotating shaft. The dual encoder module includes a main encoder and a redundant encoder. The main encoder and the redundant encoder are respectively driven by gears to the rotating shaft, and the rotation signal of the hub is collected synchronously through the gear transmission. The main control unit is electrically connected to the main encoder and the redundant encoder respectively, and is used to receive the rotation signals of the main encoder and the redundant encoder in real time, so as to obtain the distance values ​​measured by the main encoder and the redundant encoder respectively.

2. The drawstring displacement sensor according to claim 1, characterized in that, The input end of the gear drive is rigidly connected to the rotating shaft of the hub, and the output end drives the main encoder and the redundant encoder respectively, ensuring that the two encoders rotate synchronously and output independent signals.

3. The drawstring displacement sensor according to claim 1, characterized in that, The hub includes a lead screw cable laying mechanism coaxially connected to the hub, and the lead screw cable laying mechanism realizes the active cable laying of the pull rope through the cooperation of the lead screw and the nut; The rotating shaft of the hub directly drives the lead screw, and the lead screw controls the orderly winding and unwinding of the rope through the linear movement of the nut, avoiding cable overlap or jamming.

4. The drawstring displacement sensor according to claim 1, characterized in that, The aforementioned rope displacement sensor also includes a universal wheel guide mechanism, which is located at the rope outlet and is used to support the movement trajectory of the rope; The lead screw limiting device includes at least two microswitches or photoelectric switches disposed on the pull rope path to detect the maximum / minimum displacement and motion state of the pull rope.

5. The drawstring displacement sensor according to claim 4, characterized in that, The universal wheel guide mechanism includes a guide bracket and at least two universal wheels embedded in the guide bracket. The at least two universal wheels form a V-groove in the guide bracket, so that the pull rope passes through the V-groove.

6. The drawstring displacement sensor according to claim 4, characterized in that, The signal output terminal of the micro switch or photoelectric switch is connected to the main control unit via a wire. The main control unit determines whether the pull rope exceeds the safe travel based on the limit signal.

7. The drawstring displacement sensor according to claim 1, characterized in that, The main control unit is configured as follows: By comparing the output signals of the main encoder and the redundant encoder, if the difference exceeds a preset threshold, it is determined that there is interference in the signal and the signal path is switched. If both signals remain unchanged, it is determined that the pull rope or spring is damaged, and an alarm signal is triggered.

8. The drawstring displacement sensor according to claim 1, characterized in that, The spring rewinding device includes a spring, one end of which is fixed to the hub and the other end to the cable box. It is used to store energy when the cable is pulled out and to drive the hub to rotate after the cable is released, so that the spring automatically returns to its original position and wraps around the hub.

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