Dumbbell pin state monitoring sensor

Abstract

The invention provides a dumbbell pin state monitoring sensor, and belongs to the technical field of dumbbell pin state monitoring, the dumbbell pin state monitoring sensor comprises a shell, a first label, a switch and a second label, the first label, the switch and the second label are all arranged in the shell, and a reader-writer is arranged outside the shell. The switch is used for controlling the conduction state of the second tag; when the switch is in an off state, the first tag is in wireless connection with the reader-writer, and the reader-writer reads a signal of the first tag; when the dumbbell pin breaks down and is separated from the dumbbell pin groove, the switch is switched on, when the switch is in an open state, the second tag is switched on by the switch, the second tag is in wireless connection with the reader-writer, the reader-writer can read signals of the second tag, and the signals of the first tag and the second tag read by the reader-writer, namely, two signals are obtained through the reader-writer. Therefore, the state of the dumbbell pin is monitored, possible faults of the dumbbell pin are prompted, and the reliability and accuracy of fault judgment are improved.

Description

Technical Field

[0001] The present application belongs to the technical field of dumbbell pin state monitoring, and in particular relates to a dumbbell pin state monitoring sensor. Background Art

[0002] The middle troughs of the scraper conveyor in the fully-mechanized mining face of a coal mine are connected by dumbbell pins. During the coal mining process, the hydraulic support pushes the middle trough of the scraper conveyor toward the coal wall. During the pushing process, the dumbbell pin needs to withstand a large tensile force, which can easily cause damage and breakage of the dumbbell pin, resulting in the dumbbell pin falling off or being lost; at the same time, the failure of the dumbbell pin block and the spring pin can also cause the dumbbell pin to fall off or be lost. If the dumbbell pin falling off or being lost is not discovered in time, it will easily cause the middle trough connection to be misaligned or disengaged during the process of the hydraulic support pushing the middle trough to slide, affecting the normal production of the working face. The existing sensors have low reliability in monitoring the status of dumbbell pins, which affects the judgment of dumbbell pin failures. Summary of the invention

[0003] The present invention aims to solve at least one of the technical problems existing in the prior art or related art.

[0004] In view of this, according to an embodiment of the present application, a dumbbell pin state monitoring sensor is proposed, comprising:

[0005] shell;

[0006] A first tag, which is disposed in the housing and is electrically connected to a reader / writer, and the reader / writer can read the first tag;

[0007] A switch, wherein the switch is arranged in the housing;

[0008] The second tag is arranged in the housing and is electrically connected to the switch. When the switch is turned on, the second tag is connected to the reader / writer to read the second tag.

[0009] In a feasible implementation, when the switch is turned on, the reader / writer reads the first tag and the second tag simultaneously.

[0010] In a feasible implementation manner, the dumbbell pin state monitoring sensor further includes:

[0011] The battery is arranged in the housing, the battery is electrically connected to the second tag, and the battery is electrically connected to the switch; when the switch is turned on, a power-on circuit is formed, so that the battery can supply power to the second tag.

[0012] In one feasible implementation, the first tag is a passive RFID tag;

[0013] The second tag is an active RFID tag, and the second tag includes a transmitter chip, and the transmitter chip sends a signal to the reader when the switch is turned on.

[0014] In a possible implementation, the dumbbell pin includes:

[0015] Pin rod;

[0016] Two hammer heads, the hammer heads are arranged at both ends of the pin rod, and the housing is arranged on the hammer heads;

[0017] Two stoppers are provided, wherein the stopper is located at a side of the hammer head away from the middle of the pin rod, and the stopper is detachably connected to the pin rod.

[0018] In a feasible implementation manner, the dumbbell pin is installed in the dumbbell pin slot of the middle slot, a metal part is arranged in the dumbbell pin slot, and the switch is arranged close to the metal part.

[0019] In a feasible implementation manner, the switch is a magnetic switch, and the switch includes a magnetic body. The metal part attracts the magnetic body to put the switch in a closed state.

[0020] In a feasible implementation manner, the switch further includes:

[0021] An elastic member, wherein a first end of the elastic member is fixed on the magnetic body;

[0022] A shell, the shell cover is arranged on the outside of the magnetic body, and the shell is connected to the second end of the elastic member;

[0023] The base is arranged on a side of the magnetic body away from the elastic member, and the base is connected to the shell;

[0024] The contact is arranged on the side of the base close to the magnetic body. When the contact contacts the magnetic body, the switch is turned on.

[0025] In a feasible implementation, when the switch is located near the metal part, the metal part absorbs the magnetic body, so that the magnetic body is separated from the contact, and the switch is closed;

[0026] When the switch is separated from the metal part, the magnetic body contacts the contact under the action of the elastic member, and the switch is opened.

[0027] In a feasible implementation manner, at least two contacts are symmetrically arranged on the base, and the contacts extend along the circumference of the magnetic body.

[0028] Compared with the prior art, the dumbbell pin state monitoring sensor of the present application has the following beneficial effects:

[0029] The dumbbell pin state monitoring sensor provided in the embodiment of the present application includes a shell, a first tag, a switch and a second tag. The first tag, the switch and the second tag are all arranged inside the shell, and the reader is arranged outside the shell. The switch is used to control the conduction state of the second tag; when the switch is in a closed state, the first tag is wirelessly connected to the reader, and the reader reads the signal of the first tag; when the dumbbell pin fails and falls out of the dumbbell pin groove, the switch is turned on; when the switch is in an open state, the second tag is turned on by the switch, and the second tag is wirelessly connected to the reader, and the reader can read the signal of the second tag. The signals of the first tag and the second tag read by the reader, that is, two signals are obtained by the reader, and the state of the dumbbell pin is monitored accordingly, indicating that the dumbbell pin may fail, thereby improving the reliability and accuracy of fault judgment. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present application. Also, the same reference symbols are used throughout the accompanying drawings to represent the same components. In the accompanying drawings:

[0031] Figure 1 A schematic structural diagram of a dumbbell pin state monitoring sensor according to a first embodiment of the present application;

[0032] Figure 2 A schematic structural diagram of a dumbbell pin state monitoring sensor according to an embodiment of the present application from a second angle;

[0033] Figure 3 A schematic structural diagram of the installation position of a dumbbell pin state monitoring sensor according to an embodiment of the present application;

[0034] Figure 4 A schematic structural diagram of a switch of a dumbbell pin state monitoring sensor according to an embodiment of the present application;

[0035] in, Figures 1 to 4 The corresponding relationship between the reference numerals and component names in the figure is:

[0036] 11. housing; 12. first label; 13. switch; 14. second label; 15. battery; 16. dumbbell pin;

[0037] 131, magnetic body; 132, elastic member; 133, housing; 134, base; 135, contact point;

[0038] 161. Pin rod; 162. Hammer head; 163. Stop block. DETAILED DESCRIPTION

[0039] In the description of the present application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0040] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of this application, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0041] In this application, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0042] The preferred embodiments of the present application are described below in conjunction with the accompanying drawings. It should be understood that the preferred embodiments described herein are only used to illustrate and explain the present application and are not used to limit the present application.

[0043] like Figure 1 and Figure 2 As shown, according to an embodiment of the present application, a dumbbell pin state monitoring sensor is proposed, including: a shell 11, a first tag 12, a switch 13 and a second tag 14; the first tag 12 is arranged in the shell 11, the first tag 12 is electrically connected to a reader / writer, and the reader / writer can read the first tag 12; the switch 13 is arranged in the shell 11; the second tag 14 is arranged in the shell 11, the second tag 14 is electrically connected to the switch 13, and the switch 13 is turned on to make the second tag 14 conductive with the reader / writer to read the second tag 14.

[0044] The dumbbell pin state monitoring sensor provided in the embodiment of the present application includes a shell 11, a first tag 12, a switch 13 and a second tag 14. The first tag 12, the switch 13 and the second tag 14 are all arranged inside the shell 11, and the reader is arranged outside the shell 11. The switch 13 is used to control the conduction state of the second tag 14; when the switch 13 is in a closed state, the first tag 12 is wirelessly connected to the reader, and the reader reads the signal of the first tag 12; when the dumbbell pin 16 fails and escapes from the dumbbell pin 16 groove, the switch 13 is turned on; when the switch 13 is in an open state, the second tag 14 is turned on by the switch 13, and the second tag 14 is wirelessly connected to the reader, and the reader can read the signal of the second tag 14. The signals of the first tag 12 and the second tag 14 read by the reader, that is, two signals are obtained by the reader, and the state of the dumbbell pin 16 is monitored accordingly, indicating that the dumbbell pin 16 may fail, thereby improving the reliability and accuracy of fault judgment.

[0045] Furthermore, the reader is wirelessly connected to the first tag 12; when the switch 13 is in the on state, the second tag 14 is wirelessly connected to the reader, making the sensor structure independent of the reader, thereby avoiding the external line affecting the accuracy of sensor monitoring.

[0046] Furthermore, the housing 11 is a hollow cavity with an opening. After all components inside the housing 11 are installed in place, electronic potting glue is poured and sealed to fix the positions of the components to ensure the stability and reliability of the internal structure of the sensor.

[0047] In a feasible implementation, when the switch 13 is turned on, the reader / writer reads the first tag 12 and the second tag 14 simultaneously.

[0048] In this technical solution, when the switch 13 is turned on and the second tag 14 is wirelessly connected to the reader / writer, the external reader / writer can read the signals of the first tag 12 and the second tag 14 at the same time, indicating that the dumbbell pin 16 may be faulty; then, the dumbbell pin 16 at the corresponding position is searched according to the signal content of the first tag 12 and the second tag 14, thereby ensuring the accuracy of the fault detection of the dumbbell pin 16.

[0049] like Figure 1 and Figure 2 As shown, in a feasible embodiment, the dumbbell pin state monitoring sensor also includes: a battery 15; the battery 15 is arranged in the housing 11, the battery 15 is electrically connected to the second tag 14, and the battery 15 is electrically connected to the switch 13; when the switch 13 is turned on, a power-on circuit is formed, so that the battery 15 can power the second tag 14.

[0050] In this technical solution, the switch 13, the battery 15 and the second tag 14 are connected in sequence to form a circuit; when the switch 13 is closed, the circuit is disconnected, the battery 15 is disconnected from the second tag 14, and the reader only reads the signal of the first tag 12; when the switch 13 is opened, the circuit forms a loop, the battery 15 is connected to the second tag 14, and the second tag 14 is powered, and the reader reads the signals of the second tag 14 and the first tag 12 at the same time; the switch 13 is used as the switch 13 to start the battery 15, and the battery 15 is used to power the second tag 14, so as to realize the switch 13 to the second tag 12. Indirect control of the conduction state of the tag 14; when the dumbbell pin 16 is in normal use, the switch 13 and the circuit are in the disconnected state to save the power of the battery 15. The battery 15 and the circuit are in the on state only when the dumbbell pin 16 fails, ensuring that power is saved when the dumbbell pin 16 can be used normally, and then ensuring that the battery 15 has enough power to power the second tag 14 under the fault condition, so that the second tag 14 can continue to send signals to the reader and writer, maintain power supply for a longer time, and ensure that the reader and writer can continue to read the information of the second tag 14.

[0051] Specifically, two lines are led out from both sides of the switch 13, one line is connected to the positive pole of the battery 15, and the other line is connected to the positive pole of the power supply of the second tag 14; the line led out from the negative pole of the second tag 14 is connected to the negative pole of the battery 15, so that when the switch 13 is turned on, a power-on circuit is formed, thereby powering the second tag 14 through the battery 15, so that the reader can read the signal of the second tag 14.

[0052] In some examples, the battery 15 is a R2032 battery, which provides 3V power to the second tag 14 after the switch 13 is turned on.

[0053] In a feasible implementation, the first tag 12 is a passive RFID tag; the second tag 14 is an active RFID tag, and the second tag 14 includes a transmitter chip, which sends a signal to the reader when the switch 13 is turned on.

[0054] In this technical solution, the active RFID tag signal is more significant than the passive RFID tag signal. When the dumbbell pin 16 fails, the switch 13 is automatically opened, and the battery 15 supplies power to the second tag 14, so that the reader reads the signal of the second tag 14 based on the signal of the first tag 12. The reader uses the expression of the signal content of the second tag 14 as the main basis for judging the fault of the dumbbell pin 16, thereby ensuring the reliability and effectiveness of the judgment result of the dumbbell pin 16 fault.

[0055] Specifically, the first tag 12 is an ultra-high frequency passive RFID tag, the second tag 14 is an active RFID tag with a built-in wireless radio frequency transmitter chip, and the reader is an RFID reader.

[0056] In some examples, the second tag 14 has a built-in SI24R2 type 2.4 GHz wireless radio frequency transmitter chip, which can send signals to the reader when powered on.

[0057] like Figure 3 As shown, in a feasible embodiment, in a feasible embodiment, the dumbbell pin 16 includes: a pin rod 161, two hammer heads 162 and two blocks 163; the hammer heads 162 are arranged at both ends of the pin rod 161, and the shell 11 is arranged on the hammer heads 162; the block 163 is located on one side of the hammer head 162 away from the middle of the pin rod 161, and the block 163 is detachably connected to the pin rod 161.

[0058] In this technical solution, the pin rod 161 and the two hammer heads 162 are an integrated structure. The two hammer heads 162 at both ends of the pin rod 161 are respectively embedded in the dumbbell pin 16 grooves of the two docking middle grooves. The hammer heads 162 and the dumbbell pin 16 grooves are clamped together to limit the axial position of the dumbbell pin 16 body; the stopper 163 is detachably arranged on the pin rod 161. By installing the stopper 163 on the pin rod 161 and making the height of the stopper 163 greater than the height of the hammer head 162, the stopper 163 and the dumbbell pin 16 groove are clamped together in a direction perpendicular to the axis of the dumbbell pin 16 body to limit the dumbbell pin 16 body, thereby preventing the dumbbell pin 16 body from escaping from the dumbbell pin 16 groove due to a large-angle rotation. The housing 11 is installed on the hammer head 162. On the one hand, after force analysis, the sensor installed on the hammer head 162 has a relatively small effect on the force on the dumbbell pin 16, making the dumbbell pin 16 less likely to be damaged, ensuring that the original structural strength of the dumbbell pin 16 is not destroyed after the sensor is installed; on the other hand, when the block 163 falls off and the hammer head 162 and the pin rod 161 are not separated from the dumbbell pin 16 groove, the sensor on the hammer head 162 will not be separated from the metal environment provided by the metal part. Only when the hammer head 162 is also separated from the dumbbell pin 16 groove and the sensor is separated from the metal environment will it be monitored by the sensor, and the dumbbell pin 16 falling out of the dumbbell pin 16 groove is used as the trigger condition for judging the fault. The sensor quickly detects the fault of the dumbbell pin 16 falling out of the dumbbell pin 16 groove caused by the failure of the block 163, so as to improve the monitoring sensitivity of the situation where the dumbbell pin 16 falls off due to the failure of the block 163.

[0059] It is understandable that after the stopper 163 falls off, the limit of the stopper 163 is lost, and the hammer head 162 and the pin rod 161 of the dumbbell pin 16 are easy to fall out of the dumbbell pin 16 slot. The sensor is set on the hammer head 162, and the fall out of the hammer head 162 of the dumbbell pin 16 from the dumbbell pin 16 slot is used as the trigger condition for judging the fault, that is, the two middle slots completely lose the limit of the dumbbell pin 16. The fault trigger condition is more universal, which can improve the accuracy and reliability of fault monitoring and judgment results.

[0060] like Figure 3 As shown, in a feasible implementation manner, a mounting groove is provided on the hammer head 162, and the housing 11 is embedded in the mounting groove.

[0061] In this technical solution, an installation groove is provided on the hammer head 162, and the sensor is embedded in the installation groove, that is, the sensor is embedded in the hammer head 162, so as to avoid damage to the sensor during the contact and extrusion between the hammer head 162 and the middle groove. The service life of the sensor is longer, the structural reliability of the sensor is ensured, and continuous monitoring of the state of the dumbbell pin 16 is realized.

[0062] In a feasible implementation manner, the dumbbell pin 16 is installed in the dumbbell pin 16 slot of the middle slot, a metal part is arranged in the dumbbell pin 16 slot, and the switch 13 is arranged close to the metal part.

[0063] In this technical solution, after the sensor is assembled, it is installed on the dumbbell pin 16, and the dumbbell pin 16 is installed in the dumbbell pin 16 slot of the middle slot; a metal part is provided inside the dumbbell pin 16 slot, so that in the dumbbell pin 16 slot, the position corresponding to the switch 13 is a metal environment, so that the switch 13 can be controlled to be turned on or off through the position between the metal part and the switch 13, thereby judging whether the dumbbell pin 16 is faulty and detached from the middle slot through the position of the sensor.

[0064] like Figure 4 As shown, in a feasible implementation manner, the switch 13 is a magnetic switch, and a magnetic body 131 is disposed inside the switch 13. The switch 13 is in a closed state by attracting the magnetic body 131 through the metal part.

[0065] In this technical solution, the switch 13 corresponds to the metal part in the slot of the dumbbell pin 16, and the metal part attracts the magnetic body 131, so that the magnetic body 131 is close to the metal part, so that the switch 13 is in a closed state; when the dumbbell pin 16 is separated from the middle slot, the magnetic body 131 of the sensor is separated from the metal part, and the metal part cannot attract the magnetic body 131, so that the magnetic body 131 is reset, and the switch 13 is opened. The dumbbell pin 16 is separated from the dumbbell pin 16 slot as a trigger condition for judging the fault. The fault trigger condition is more universal, so as to improve the accuracy and reliability of the fault judgment result.

[0066] Furthermore, when the dumbbell pin 16 breaks or the blocks 163 at both ends of the dumbbell pin 16 fall off or other faults cause the dumbbell pin 16 to fall out of the dumbbell pin 16 slot, the sensor detaches from the metal part, the attraction condition of the magnetic body 131 disappears, and the switch 13 is turned on.

[0067] like Figure 4As shown, in a feasible embodiment, the switch 13 also includes: an elastic member 132, a shell 133, a base 134 and a contact 135; the first end of the elastic member 132 is fixed on the magnetic body 131; the shell 133 is covered on the outside of the magnetic body 131, and the shell 133 is connected to the second end of the elastic member 132; the base 134 is arranged on the side of the magnetic body 131 away from the elastic member 132, and the base 134 is connected to the shell 133; the contact 135 is arranged on the side of the base 134 close to the magnetic body 131, and when the contact 135 contacts the magnetic body 131, the switch 13 is turned on.

[0068] In this technical solution, the shell 133 is connected to the base 134, the magnetic body 131 is arranged in the shell 133, a contact 135 is arranged on the side surface of the magnetic body 131 close to the base 134, and an elastic member 132 is connected to the side surface of the magnetic body 131 away from the base 134. When the magnetic attraction between the metal part and the magnetic body 131 is less than the restoring force of the elastic member 132, the elastic member 132 applies a thrust to the magnetic body 131, so that the magnetic body 131 can be tightly attached to the two contacts 135 of the positive pole and the negative pole, and the two contacts 135 are turned on, thereby turning on the switch 13, so that the switch 13 is opened and the switch 13 is in the on state.

[0069] Furthermore, a conical positioning groove is provided on one side of the magnetic body 131 away from the base 134, the elastic member 132 is conical and matches the positioning groove, and the small head end of the elastic member 132 is embedded in the positioning groove to ensure the stability of the contact between the magnetic body 131 and the elastic member 132.

[0070] Furthermore, a guide rod is provided inside the shell 133 along the axial direction of the shell 133. When the elastic member 132 and the magnetic body 131 are installed in place, the guide rod can pass through the elastic member 132 and the magnetic body 131 to guide the movement of the magnetic body 131 and ensure the smooth movement of the magnetic body 131.

[0071] In a feasible implementation, when the switch 13 is located near the metal part, the metal part absorbs the magnetic body 131, so that the magnetic body 131 is separated from the contact 135, and the switch 13 is closed; when the switch 13 is separated from the metal part, the magnetic body 131 contacts the contact 135 under the action of the elastic member 132, and the switch 13 is opened.

[0072] In this technical solution, when the dumbbell pin 16 is installed in the dumbbell pin 16 slot, the magnetic body 131 is located close to the metal part, the metal part attracts the magnetic body 131 close to the metal part and compresses the elastic member 132, so that the magnetic body 131 is separated from the contact 135, and the switch 13 is in the off state at this time; when the dumbbell pin 16 is detached from the dumbbell pin 16 slot, the magnetic body 131 is away from the metal part, the attraction of the metal part to the magnetic body 131 disappears, and the elastic member 132 restores its elastic deformation, pushing the magnetic body 131 to move in the direction close to the contact 135, so that the magnetic body 131 is in contact with the contact 135, and the switch 13 is in the on state at this time, and the switch 13 is turned on.

[0073] like Figure 4 As shown, in a feasible implementation manner, at least two contacts 135 are symmetrically arranged on the base 134 , and the contacts 135 extend along the circumference of the magnetic body 131 .

[0074] In this technical solution, after the switch 13 is assembled, the elastic member 132 can press the magnetic body 131 tightly against the contact 135 of the base 134 without being affected by the outside world, so that the magnetic body 131 contacts the contact 135; at this time, the magnetic body 131 acts as a conductor to connect the two contacts 135 on the base 134, so that the switch 13 is in a conducting state, that is, the switch 13 is turned on; by extending the contact 135 along the circumference of the magnetic body 131, it is ensured that the contact 135 and the magnetic body 131 can be fully in contact, thereby preventing disconnection and ensuring the stability of the switch 13 after being turned on.

[0075] Furthermore, a wiring portion is provided on the contact 135 , and the wiring portion extends in a direction away from the center of the base 134 to the outside of the magnetic body 131 and the housing 133 , so as to facilitate wiring on the switch 13 .

[0076] It is easy for those skilled in the art to understand that the above-mentioned advantageous methods can be freely combined and superimposed without conflict.

[0077] The above are only preferred embodiments of the present application and are not intended to limit the present application. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present application shall be included in the protection scope of the present application. The above are only preferred implementations of the present application. It should be pointed out that for ordinary technicians in this technical field, several improvements and variations can be made without departing from the technical principles of the present application, and these improvements and variations should also be regarded as the protection scope of the present application.

Claims

1. A dumbbell pin state monitoring sensor, characterized in that: The dumbbell pin state monitoring sensor comprises: shell; A first tag, wherein the first tag is disposed in the housing, the first tag is electrically connected to a reader / writer, and the reader / writer can read the first tag; a switch, wherein the switch is disposed in the housing; The second tag is arranged in the housing, the second tag is electrically connected to the switch, and the second tag is connected to the reader / writer by turning on the switch to read the second tag.

2. A dumbbell pin state monitoring sensor according to claim 1, characterized in that: When the switch is turned on, the reader / writer reads the first tag and the second tag simultaneously.

3. A dumbbell pin state monitoring sensor according to claim 2, characterized in that: The dumbbell pin state monitoring sensor also includes: A battery is disposed in the housing, the battery is electrically connected to the second tag, and the battery is electrically connected to the switch; when the switch is turned on, a power-on circuit is formed, so that the battery can supply power to the second tag.

4. A dumbbell pin state monitoring sensor according to claim 3, characterized in that: The first tag is a passive RFID tag; The second tag is an active RFID tag, and the second tag includes a transmitter chip, and the transmitter chip sends a signal to the reader when the switch is turned on.

5. A dumbbell pin state monitoring sensor according to claim 2, characterized in that: The dumbbell pin comprises: Pin rod; Two hammer heads, the hammer heads are arranged at two ends of the pin rod, and the housing is arranged on the hammer heads; Two stoppers are provided, wherein the stoppers are located on a side of the hammer head away from the middle of the pin rod, and the stoppers are detachably connected to the pin rod.

6. A dumbbell pin state monitoring sensor according to claim 5, characterized in that: The dumbbell pin is installed in the dumbbell pin slot of the middle slot, a metal part is arranged in the dumbbell pin slot, and the switch is arranged close to the metal part.

7. A dumbbell pin state monitoring sensor according to claim 6, characterized in that: The switch is a magnetic switch, and the switch includes a magnetic body. The metal part attracts the magnetic body, so that the switch is in a closed state.

8. A dumbbell pin state monitoring sensor according to claim 7, characterized in that: The switch also includes: An elastic member, a first end of which is fixed on the magnetic body; A shell, the shell is covered on the outside of the magnetic body, and the shell is connected to the second end of the elastic member; A base, the base is arranged on a side of the magnetic body away from the elastic member, and the base is connected to the shell; The contact point is arranged on the side of the base close to the magnetic body, and the switch is turned on when the contact point contacts the magnetic body.

9. A dumbbell pin state monitoring sensor according to claim 8, characterized in that: When the switch is located near the metal part, the metal part absorbs the magnetic body, so that the magnetic body is separated from the contact point, and the switch is closed; When the switch is separated from the metal part, the magnetic body contacts the contact point under the action of the elastic member, and the switch is opened.

10. A dumbbell pin state monitoring sensor according to claim 8, characterized in that: At least two contacts are symmetrically arranged on the base, and the contacts extend along the circumference of the magnetic body.

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