Bidirectional limit switch device convenient for remote replacement operation

Abstract

The invention discloses a bidirectional limit switch device convenient for remote replacement operation, and belongs to the technical field of limit control of motion stroke in electromechanical equipment. Comprising two blocking pieces, two limiting switches, two transmission rods located between the two blocking pieces, two reset springs, four linear bearings, two reset fixing pieces, a limiting switch assembly and an installation base, the installation base is installed on a moving part and located between the two transmission rods, and the limiting switch assembly comprises a limiting switch base; the limit switch seat is directly inserted into the mounting seat, the two limit switches are respectively mounted on the limit switch seat, one end of each transmission rod can be close to the limit switch seat and can be in contact with the contact piece of the corresponding limit switch, and the other end of each transmission rod can be close to the corresponding blocking piece and can be in contact with the corresponding blocking piece. The purpose of remotely replacing the limit switch through the transmission part can be achieved, the personal safety of operators is protected, the replacement operation is simple and rapid, and the efficiency is high.

Description

Technical Field

[0001] The present invention belongs to the technical field of limit control of motion stroke in electromechanical equipment, and specifically relates to a limit switch device, and in particular to a bidirectional limit switch device which is convenient for remote replacement operation. Background Art

[0002] Limit switch devices are generally used to control the movement stroke of equipment or components. Their basic components include blocking members (such as baffles, blocks or raised blocking parts, etc.) and limit switches (also called travel switches, contact sensors, etc.). In applications, the blocking members and limit switches are respectively installed on the fixed parts and moving parts of the equipment. Generally, the limit switch is installed on the moving part. When the moving part moves to the extreme position, the contact piece of the limit switch contacts and is blocked by the blocking member. The limit switch outputs a signal to the controller, and the controller sends a control signal to stop the moving part from moving, thereby realizing the movement stroke limit control function.

[0003] In most application scenarios, the travel limit control of moving parts is bidirectional control, that is, the movement travel of the moving parts in two opposite directions on the same straight line is limited separately. The limit switch device used is a bidirectional limit switch device, which generally has two blocking members and two limit switches.

[0004] Traditional two-way limit switch devices generally use screws to install two limit switches on both sides of the moving parts, which fully meets the application requirements in general application scenarios. However, when used in some highly polluted environments, there is a disadvantage that it is difficult to replace the limit switch at a long distance. For example, in the nuclear waste reprocessing industry, power manipulators are usually used to participate in the handling and processing of nuclear waste; as an electric-controlled manipulator, the power manipulator needs to be limited in its movement stroke to avoid collision with other equipment at high speed, so limit switches are installed at both ends of one side of the mobile bracket where the power manipulator is installed.

[0005] For the bidirectional limit switch device in the above-mentioned high-pollution environment, since electronic equipment has a shortened lifespan to varying degrees, in order for the equipment to operate stably and reliably, the limit switch needs to be replaced at a fixed time period. If a traditional bidirectional limit switch device is used, there are the following defects: the two limit switches are fixedly installed on the moving parts respectively, and the replacement requires human intervention and installation. Remote replacement cannot be achieved through transmission parts, resulting in safety hazards for operators. In addition, the replacement steps are many, the process is cumbersome, time-consuming, the replacement operation efficiency is low, and the equipment maintenance cost is increased. Summary of the invention

[0006] The purpose of the present invention is to provide a bidirectional limit switch device suitable for a highly polluted environment and convenient for remote replacement operation in order to solve the above-mentioned problem.

[0007] The present invention achieves the above-mentioned purpose through the following technical solutions:

[0008] A two-way limit switch device convenient for remote replacement operation comprises two blocking members and two limit switches, wherein the two blocking members are respectively mounted on a fixed member, the two limit switches are respectively mounted on a movable member, and the two limit switches are located between the two blocking members. The two-way limit switch device convenient for remote replacement operation further comprises two transmission rods located between the two blocking members, two reset springs, four linear bearings, two reset fixed members, a limit switch assembly, and a mounting seat, wherein the mounting seat is mounted on the movable member and located between the two transmission rods, the limit switch assembly comprises a limit switch seat, the limit switch seat is directly mounted on the mounting seat, and the two limit switches are located between the two blocking members. The limit switches are respectively installed on the limit switch seats, the two transmission rods whose center lines are located on the same straight line are respectively installed on the moving parts through the linear bearings, each of the transmission rods passes through the central through holes of the corresponding two linear bearings, one end of each transmission rod can be close to the limit switch seat and can contact the corresponding contact piece of the limit switch, and the other end can be close to the corresponding blocking piece and contact it, the two reset fixing members are respectively installed on the moving parts and close to the two transmission rods, the two reset springs are respectively installed between the two transmission rods and the corresponding reset fixing members and respectively make the two transmission rods have reset elastic force away from the limit switch seat.

[0009] Preferably, in order to facilitate the installation of the limit switch and facilitate reliable contact between the transmission rod and the contact piece of the limit switch, an installation groove is provided on the limit switch seat, and the two limit switches are respectively installed in the installation groove near the two ends, and one end of the two transmission rods can contact the corresponding contact piece of the limit switch after entering the installation groove respectively.

[0010] Preferably, in order to facilitate the transmission of the electrical signal of the limit switch to the controller on the moving part through conductive contact, the limit switch seat is provided with a switch seat wireless contact terminal including a plurality of conductive contacts for transmitting electrical signals, the switch seat wireless contact terminal is electrically connected to the limit switch, and a mounting seat wireless contact terminal including a plurality of conductive contacts for transmitting electrical signals is provided at a position on the mounting seat corresponding to the switch seat wireless contact terminal, the mounting seat wireless contact terminal is correspondingly connected to the controller on the moving part, and the mounting seat wireless contact terminal and the switch seat wireless contact terminal can be conductively connected accordingly.

[0011] Preferably, in order to realize the quick plug-in connection and separation between the limit switch seat and the mounting seat by vertical movement, the axial direction of the transmission rod is horizontal, the length direction of the mounting groove is horizontal, a vertical mounting plate is provided on the upper part of the mounting seat, two wireless contact ends of the mounting seat are arranged at the upper end of the mounting seat and the lower part of the mounting plate is located between the two wireless contact ends of the mounting seat, a side of the mounting plate close to the moving part protrudes outward to form a connecting part, and a connecting screw passes through the corresponding through holes on the mounting plate and the connecting part and is connected with the corresponding screw hole on the moving part, a vertically penetrating limit groove is provided on the side of the limit switch seat close to the moving part, a groove wall opening that penetrates both inside and outside and vertically is provided in the middle of the groove wall between the limit groove and the moving part, the mounting plate is placed in the limit groove, the connecting part passes through the groove wall opening, a docking hook is provided in the middle of the upper end of the limit switch seat, and the two wireless contact ends of the switch seat are respectively arranged at the lower end of the limit switch seat and are respectively located directly above the two wireless contact ends of the mounting seat.

[0012] Preferably, in order to facilitate the temporary positioning function between the limit switch seat and the mounting seat and to have adaptive elasticity to avoid affecting the connection and separation between the two, circular positioning grooves are respectively provided on the outer surface of the groove wall between the limit groove and the movable part, and on both sides of the groove wall opening, glass bead springs are respectively installed at positions corresponding to the two positioning grooves on the movable part, and the glass beads of the glass bead springs can be placed in the corresponding positioning grooves.

[0013] Preferably, in order to avoid damage to the glass bead spring due to prolonged compression contact between the glass bead spring and the limit switch seat during the connection and separation process between the limit switch seat and the mounting seat, vertical strip-shaped clearance grooves with open lower ends are respectively provided on the outer surface of the groove wall between the limit groove and the moving part at positions below the two positioning grooves.

[0014] Preferably, in order to realize a reliable limit control function in which the moving part first slows down and then stops, a third limit switch is also installed in the middle position between the two limit switches in the installation groove, and one end of the two transmission rods can contact the contact piece of the third limit switch after entering the installation groove, and the third limit switch is electrically connected to the inner end of the wireless contact end of the switch seat.

[0015] Preferably, in order to better protect the limit switch, a protection plate for protecting the limit switch is installed on the limit switch seat near the mounting groove.

[0016] Preferably, in order to better enable the transmission rod to have a reset elastic force away from the limit switch seat, a convex ring protruding toward the outer circumferential direction is provided at a position between the corresponding two linear bearings on the transmission rod, and the convex ring is located between the corresponding reset fixing piece and the corresponding linear bearing close to the limit switch seat. The reset spring is sleeved on the outside of the transmission rod and is located between the corresponding convex ring and the corresponding linear bearing close to the limit switch seat, and the reset spring is a compression spring.

[0017] The beneficial effects of the present invention are:

[0018] The present invention installs two or three limit switches on a limit switch base, and installs movable and resettable transmission rods outside the two ends of the limit switch base respectively, and uses the transmission rod to transmit the trigger power signal of the moving part contacting the blocking part when the moving part approaches the limit position to the corresponding limit switch, thereby realizing a normal trigger function, and the mounting base is installed on the moving part, and the limit switch base is directly installed on the mounting base. When replacing the limit switch, it is only necessary to pull out or insert the limit switch base from the mounting base with a long-distance transmission member similar to a long rod, so as to realize the separation or connection function between the limit switch base and the mounting base, thereby realizing the purpose of completing the long-distance replacement of the limit switch through the transmission member, without the need for the operator to directly contact the limit switch base and the limit switch, the operator can operate outside the high-pollution space, thereby protecting the personal safety of the operator, and the replacement operation is simple and fast, with high efficiency, reducing the equipment maintenance cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a three-dimensional diagram of the bidirectional limit switch device for facilitating remote replacement operation according to the present invention when in use;

[0020] Figure 2 It is one of the three-dimensional views of the limit switch seat of the bidirectional limit switch device that is convenient for remote replacement operation according to the present invention;

[0021] Figure 3 The second is a three-dimensional diagram of the limit switch seat of the two-way limit switch device that is convenient for long-distance replacement operation according to the present invention, and Figure 2 The perspective is different;

[0022] Figure 4 The third is a three-dimensional diagram of the limit switch seat of the two-way limit switch device that is convenient for long-distance replacement operation according to the present invention, and Figure 2 and Figure 3 The perspectives are different;

[0023] Figure 5 It is a partially cutaway stereoscopic diagram of the bidirectional limit switch device for facilitating remote replacement operation according to the present invention when in use;

[0024] Figure 6 It is a partial stereoscopic diagram of the connection and separation of the limit switch seat and the mounting seat of the bidirectional limit switch device that is convenient for long-distance replacement operation according to the present invention. DETAILED DESCRIPTION

[0025] The present invention will be further described below in conjunction with the accompanying drawings:

[0026] like Figure 1-Figure 6 As shown, the bidirectional limit switch device for facilitating remote replacement operation of the present invention comprises two blocking members 1 ( Figure 1 Only one blocking member 1 is shown, and the other blocking member 1 is located at a distal position on the fixed member 8 and is not visible in the figure), two limit switches 72 and two transmission rods 2 located between the two blocking members 1, two reset springs 5, four linear bearings 6, two reset fixed members 3, a limit switch assembly 7, and a mounting seat 16. The two blocking members 1 are respectively mounted on the fixed member 8, and the two limit switches 72 are respectively mounted on the moving member 9. The two limit switches 72 are located between the two blocking members 1. The mounting seat 16 is mounted on the moving member 9 and between the two transmission rods 2. The limit switch assembly 7 includes a limit switch seat 70, and the limit switch seat 70 is directly installed on the mounting seat 16 , two limit switches 72 are respectively installed on the limit switch seat 70, and the two transmission rods 2 whose center lines are located on the same straight line are respectively installed on the moving part 9 through linear bearings 6. Each transmission rod 2 passes through the central through hole of the corresponding two linear bearings 6. One end of each transmission rod 2 can be close to the limit switch seat 70 and can contact the contact piece of the corresponding limit switch 72, and the other end can be close to the corresponding blocking piece 1 and contact it. Two reset fixing members 3 are respectively installed on the moving part 9 and are respectively close to the two transmission rods 2. Two reset springs 5 ​​are respectively installed between the two transmission rods 2 and the corresponding reset fixing members 3 and respectively make the two transmission rods 2 have a reset elastic force away from the limit switch seat 70. Figure 1 Also shown are rollers (not marked in the figure) provided on the movable component 9. The two rollers are respectively placed on the tracks of the fixed component 8 to realize the rolling movement function of the movable component 9. This is a conventional structure designed according to application needs. The above-mentioned movable component 9 and fixed component 8 are determined according to the electromechanical equipment actually used. The present invention does not limit the specific structure and application equipment of the movable component 9 and the fixed component.

[0027] like Figure 1-Figure 6 As shown, the present invention also discloses the following more optimized specific structures:

[0028] In order to facilitate the installation of the limit switch 72 and facilitate reliable contact between the transmission rod 2 and the contact piece of the limit switch 72, an installation groove 71 is provided on the limit switch seat 70, and the two limit switches 72 are respectively installed in the installation groove 71 near the two ends. After one end of the two transmission rods 2 enters the installation groove 71 respectively, they can contact the corresponding contact piece of the limit switch 72.

[0029] In order to facilitate the transmission of the electrical signal of the limit switch 72 to the controller on the moving part 9 (not visible in the figure) through conductive contact, the limit switch seat 70 is provided with a switch seat wireless contact terminal 77 including a plurality of conductive contacts for transmitting electrical signals. The switch seat wireless contact terminal 77 is electrically connected to the limit switch 72, and a mounting seat wireless contact terminal 13 including a plurality of conductive contacts for transmitting electrical signals is provided at a position corresponding to the switch seat wireless contact terminal 77 on the mounting seat 16. The mounting seat wireless contact terminal 13 is correspondingly connected to the controller on the moving part 9, and the mounting seat wireless contact terminal 13 and the switch seat wireless contact terminal 77 can be conductively connected accordingly.

[0030] In order to realize the quick plug-in connection and separation between the limit switch seat 70 and the mounting seat 16 by vertical movement, the axial direction of the transmission rod 2 is horizontal, the length direction of the mounting groove 71 is horizontal, and a vertical mounting plate 15 is provided on the upper part of the mounting seat 16. Two mounting seat wireless contact ends 13 are arranged at the upper end of the mounting seat 16 and the lower part of the mounting plate 15 is located between the two mounting seat wireless contact ends 13. The side of the mounting plate 15 close to the moving part 9 protrudes outward to form a connecting portion 10. The connecting screw (not marked in the figure) passes through the mounting plate 15 and the connecting portion 10. The corresponding through hole on the upper side is connected with the corresponding screw hole on the moving part 9. A vertically penetrating limit groove 76 is provided on the side of the limit switch seat 70 close to the moving part 9. A slot wall opening 75 that penetrates both inside and outside and vertically is provided in the middle of the slot wall between the limit groove 76 and the moving part 9. The mounting plate 15 is placed in the limit groove 76. The connecting part 10 passes through the slot wall opening 75. A docking hook 74 is provided in the middle of the upper end of the limit switch seat 70. Two switch seat wireless contact terminals 77 are respectively provided at the lower end of the limit switch seat 70 and are respectively located directly above the two mounting seat wireless contact terminals 13. The two switch seat wireless contact terminals 77 and the two mounting seat wireless contact terminals 13 are redundant designs, which are equivalent to two groups of identical electrical connection components, and each group of electrical connection components includes a switch seat wireless contact terminal 77 and a mounting seat wireless contact terminal 13 corresponding to each other.

[0031] In order to facilitate the temporary positioning function between the limit switch seat 70 and the mounting seat 16 and have adaptive elasticity to avoid affecting the connection and separation between the two, circular positioning grooves 78 are respectively provided on the outer surface of the groove wall between the limit groove 76 and the movable part 9 at positions on both sides of the groove wall opening 75, and glass bead springs 12 are respectively installed at positions corresponding to the two positioning grooves 78 on the movable part 9, and the glass beads 11 of the glass bead springs 12 can be placed in the corresponding positioning grooves 78.

[0032] In order to prevent the glass bead 11 of the glass bead spring 12 from being in long-term compression contact with the limit switch seat 70 during the connection and separation process between the limit switch seat 70 and the mounting seat 16, which may damage the glass bead spring 12, vertical strip-shaped clearance grooves 79 with open lower ends are respectively provided on the outer surface of the groove wall between the limit groove 76 and the movable part 9 at positions below the two positioning grooves 78.

[0033] In order to realize the reliable limit control function of slowing down the moving part 9 before stopping, a third limit switch 72 is installed in the middle position between the two limit switches 72 in the installation groove 71. After one end of the two transmission rods 2 enters the installation groove 71, they can contact the contact piece of the third limit switch 72. The third limit switch 72 is electrically connected to the inner end of the wireless contact end 77 of the switch seat.

[0034] In order to better protect the limit switch 72 , a protection plate 73 for protecting the limit switch 73 is installed on the limit switch seat 70 near the mounting groove 71 .

[0035] In order to better enable the transmission rod 2 to have a reset elastic force away from the limit switch seat 70, a convex ring 4 protruding toward the outer circumferential direction is provided at a position between the corresponding two linear bearings 6 on the transmission rod 2. The convex ring 4 is located between the corresponding reset fixing piece 3 and the corresponding linear bearing 6 close to the limit switch seat 70. The reset spring 5 is sleeved on the outside of the transmission rod 2 and is located between the corresponding convex ring 4 and the corresponding linear bearing 6 close to the limit switch seat 70. The reset spring 5 is a compression spring.

[0036] like Figure 1-Figure 6As shown, when used, the moving part 9 rolls on the track of the fixed part 8 through the roller. When the moving part 9 moves to the extreme position close to one end, the corresponding transmission rod 2 will contact with the corresponding blocking member 1 and be blocked by the blocking member 1. The blocking member 1 gives a reaction force to the transmission rod 2, and the reaction force enables the transmission rod 2 to overcome the elastic force of the reset spring 5 and move toward the direction close to the limit switch seat 70. When one end of the transmission rod 2 moves to contact with a contact piece of a limit switch 72, the limit switch 72 is triggered, causing it to send a signal and transmit it to the controller on the moving part 9 through the corresponding switch seat wireless contact terminal 77 and the mounting seat wireless contact terminal 13. , then the driving component (not shown in the figure) of the moving component 9 is controlled to start to decelerate the moving component 9 (if there is no third limit switch 72, it will stop running directly). When one end of the transmission rod 2 moves to contact with the contact of the third limit switch 72 (i.e. the limit switch 72 in the middle position), the limit switch 72 is triggered to send out a signal and transmit it to the controller on the moving component 9 through the corresponding switch seat wireless contact terminal 77 and the mounting seat wireless contact terminal 13. Then the driving component (not shown in the figure) of the moving component 9 is controlled to stop the moving component 9, so as to realize the motion stroke limit control function of the moving component 9. The reverse motion stroke limit control process of the moving component 9 is similar to this and will not be repeated here.

[0037] When the limit switch 72 needs to be replaced, the operator outside the equipment room docks the docking hook 74 through a long-distance transmission member 14 similar to a long rod (it can also be other components as long as it can achieve this function) (for example, the operator extends the long rod downward from the observation window or maintenance port on the top of the workshop to dock with the docking hook 74), and then uses manual or lifting equipment to pull out the limit switch seat 70 from the mounting seat 16, so that the separation function between the limit switch seat 70 and the mounting seat 16 can be achieved; after the operator replaces and installs the limit switch 72 on the limit switch seat 70 outside, the operator docks the docking hook 74 through the long-distance transmission member 14, and then uses manual or lifting equipment to insert the limit switch seat 70 from the mounting seat 16, so that the connection function between the limit switch seat 70 and the mounting seat 16 can be achieved, so that the replacement and maintenance work of the limit switch is completed, and the operator can operate outside the highly polluted space, thereby protecting the personal safety of the operator, and the replacement operation is simple, fast, and efficient, thereby reducing the equipment maintenance cost.

[0038] The above embodiments are only preferred embodiments of the present invention and are not limitations of the technical solutions of the present invention. Any technical solution that can be implemented on the basis of the above embodiments without creative work should be deemed to fall within the scope of protection of the patent of the present invention.

Claims

1. A bidirectional limit switch device convenient for remote replacement operation, comprising two blocking members and two limit switches, wherein the two blocking members are respectively mounted on a fixed member, the two limit switches are respectively mounted on a movable member, and the two limit switches are located between the two blocking members, characterized in that: The bidirectional limit switch device convenient for remote replacement operation also includes two transmission rods, two reset springs, four linear bearings, two reset fixings, a limit switch assembly, and a mounting seat located between the two blocking members. The mounting seat is installed on the moving member and located between the two transmission rods. The limit switch assembly includes a limit switch seat, which is directly inserted and installed on the mounting seat. The two limit switches are respectively installed on the limit switch seat. The two transmission rods whose center lines are located on the same straight line are respectively installed on the moving member through the linear bearings. Each transmission rod passes through the central through hole of the corresponding two linear bearings. One end of each transmission rod can be close to the limit switch seat and can contact the corresponding contact member of the limit switch, and the other end can be close to the corresponding blocking member and contact it. The two reset fixings are respectively installed on the moving member and close to the two transmission rods. The two reset springs are respectively installed between the two transmission rods and the corresponding reset fixings and respectively make the two transmission rods have reset elastic forces away from the limit switch seat.

2. The bidirectional limit switch device that is convenient for remote replacement operation according to claim 1 is characterized in that: The limit switch seat is provided with a mounting groove, and the two limit switches are respectively mounted in the mounting groove at positions close to both ends, and one end of the two transmission rods can contact the corresponding contact piece of the limit switch after entering the mounting groove respectively.

3. The bidirectional limit switch device that is convenient for remote replacement operation according to claim 2 is characterized in that: The limit switch seat is provided with a switch seat wireless contact terminal including a plurality of conductive contacts for transmitting electrical signals, and the switch seat wireless contact terminal is electrically connected to the limit switch. A mounting seat wireless contact terminal including a plurality of conductive contacts for transmitting electrical signals is provided at a position on the mounting seat corresponding to the switch seat wireless contact terminal, and the mounting seat wireless contact terminal is correspondingly connected to the controller on the moving part, and the mounting seat wireless contact terminal and the switch seat wireless contact terminal can be correspondingly conductively connected.

4. The bidirectional limit switch device that is convenient for remote replacement operation according to claim 3 is characterized in that: With the axial direction of the transmission rod as the transverse direction and the length direction of the mounting groove as the transverse direction, a vertical mounting plate is provided on the upper part of the mounting seat, two wireless contact ends of the mounting seat are arranged at the upper end of the mounting seat and the lower part of the mounting plate is located between the two wireless contact ends of the mounting seat, a side of the mounting plate close to the moving part protrudes outward to form a connecting portion, and a connecting screw passes through the corresponding through holes on the mounting plate and the connecting portion and is connected with the corresponding screw hole on the moving part, a vertically penetrating limit groove is provided on the side of the limit switch seat close to the moving part, a groove wall opening that penetrates both inside and outside and vertically is provided in the middle of the groove wall between the limit groove and the moving part, the mounting plate is placed in the limit groove, the connecting portion passes through the groove wall opening, a docking hook is provided in the middle part of the upper end of the limit switch seat, and the two wireless contact ends of the switch seat are respectively arranged at the lower end of the limit switch seat and are respectively located directly above the two wireless contact ends of the mounting seat.

5. The bidirectional limit switch device that is convenient for remote replacement operation according to claim 4 is characterized in that: Circular positioning grooves are respectively provided on the outer surface of the groove wall between the limiting groove and the movable part at positions on both sides of the groove wall opening, and glass bead springs are respectively installed at positions corresponding to the two positioning grooves on the movable part, and the glass beads of the glass bead springs can be placed in the corresponding positioning grooves.

6. The bidirectional limit switch device that is convenient for remote replacement operation according to claim 5 is characterized in that: Vertical strip-shaped clearance grooves with open lower ends are respectively provided at positions below the two positioning grooves on the outer surface of the groove wall between the limiting groove and the moving part.

7. The bidirectional limit switch device for facilitating remote replacement operation according to any one of claims 3 to 6, characterized in that: A third limit switch is also installed in the installation groove at the middle position between the two limit switches. After one end of the two transmission rods enters the installation groove, they can contact the contact piece of the third limit switch. The third limit switch is electrically connected to the inner end of the wireless contact end of the switch seat.

8. The bidirectional limit switch device for facilitating remote replacement operation according to any one of claims 2 to 6, characterized in that: A protection plate for protecting the limit switch is installed on the limit switch seat near the mounting groove.

9. The bidirectional limit switch device for facilitating remote replacement operation according to any one of claims 1 to 6, characterized in that: A convex ring protruding toward the outer circumferential direction is provided on the transmission rod at a position between the corresponding two linear bearings, and the convex ring is located between the corresponding reset fixing piece and the corresponding linear bearing close to the limit switch seat. The reset spring is sleeved outside the transmission rod and located between the corresponding convex ring and the corresponding linear bearing close to the limit switch seat, and the reset spring is a compression spring.

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