Travel switch with self-locking function

Abstract

The present application belongs to the technical field of travel switches, and particularly relates to a travel switch with a self-locking function. Compared with the prior art, when the push rod of the present application corresponds to the first position and the second position, the limiting column can be positioned at the third position or the fourth position, so that the position of the transmission shaft is relatively fixed to complete self-locking. Further, through the arrangement of the first positioning groove and the second positioning groove, the end of the limiting column can be positioned in the second positioning groove to complete positioning, so that the transmission shaft completes self-locking. The present application solves the problem that the travel switch in the prior art uses a single roller for switching, and after the position is switched, the roller cannot form self-locking, and in the case of swinging and vibration (for example, a marine environment), the use is prone to the problem of signal loss. Through the arrangement of the transition piece, the locking piece can be prevented from directly contacting the sealing ring, and the locking piece can be prevented from driving the sealing ring when being tightened, so that the sealing ring is twisted and deformed, thereby affecting the sealing performance.

Description

Technical Field

[0001] This invention belongs to the technical field of limit switches, specifically relating to a limit switch with a self-locking function. Background Technology

[0002] Limit switches, also known as position switches, are a type of commonly used low-current control electrical device. They utilize the impact of moving parts in production machinery to actuate their contacts, thereby connecting or disconnecting control circuits to achieve specific control objectives. Typically, these switches are used to limit the position or travel of mechanical movement, causing the machinery to automatically stop, reverse, change speed, or automatically reciprocate at a certain position or travel distance.

[0003] Existing limit switches use a single roller for switching. After the position is switched, the roller cannot form a self-locking function. In situations with swaying and vibration (such as marine environments), signal loss is likely to occur. Therefore, a limit switch with a self-locking function is needed. Summary of the Invention

[0004] The technical problem to be solved by the present invention is that the limit switch in the prior art uses a single roller for switching. After the position is switched, the roller cannot form a self-locking function. In the case of swaying and vibration (such as marine environment), it is easy to lose signal. In order to solve the above problems, the present invention provides a limit switch with a self-locking function.

[0005] The objective of this invention is achieved in the following manner: a limit switch with a self-locking function includes a base, a switch assembly is disposed inside the base, a push rod assembly is disposed at one end of the switch assembly, a push rod is disposed at the end of the push rod assembly away from the switch assembly, a switching part of a drive shaft is connected to the end of the push rod away from the push rod assembly, a limiting post is disposed on the side of the switching part of the drive shaft away from the push rod, and a first position, a second position, a third position and a fourth position are disposed on the switching part. When the push rod is switched to the first position, the end of the limiting post is connected to the first positioning groove in the third position. When the push rod is switched to the second position, the end of the limiting post is connected to the second positioning groove in the fourth position. The axial distance from the first position to the drive shaft is less than the axial distance from the second position to the drive shaft. A rotating rod is disposed at one end of the base, and a wire inlet unit is disposed at the other end of the base. The rotating rod is connected to the drive shaft.

[0006] The end of the limiting post away from the drive shaft is connected to an elastic component, and the end of the elastic component away from the limiting post is connected to the inner surface of the base.

[0007] A wavy arc is set at the first position.

[0008] The rotating rod is equipped with a first sliding wheel and a second sliding wheel.

[0009] The incoming line unit includes a sealing ring, a locking element, and a transition element. The base has a hole, the sealing ring is placed inside the hole, the locking element is threaded to the hole and presses the sealing ring, the cable passes through the locking element and the sealing ring and is connected to the switch assembly, and a transition element is provided between the locking element and the sealing ring.

[0010] The roughness of the contact surface between the transition member and the sealing ring is greater than the roughness of the contact surface between the transition member and the locking member.

[0011] The locking element is made of plastic.

[0012] Compared to existing technologies, in this invention, when the push rod corresponds to the first and second positions respectively, the limiting post can be positioned in the third or fourth position to fix the position of the transmission shaft and achieve self-locking. Furthermore, by setting the first and second positioning grooves, the end of the limiting post can be positioned in the second positioning groove to complete the positioning, thereby enabling the transmission shaft to achieve self-locking. This solves the problem in existing technologies where the limit switch uses a single roller for switching, and after the position is switched, the roller cannot form a self-locking mechanism, which can easily lead to signal loss in situations with swaying and vibration (such as marine environments). By setting the transition piece, the locking piece can be prevented from directly contacting the sealing ring, and the locking piece can be prevented from driving the sealing ring when tightening, causing the sealing ring to twist and deform, thereby affecting the sealing performance. Attached Figure Description

[0013] Figure 1 This is a front view of a limit switch with a self-locking function.

[0014] Figure 2 A cross-section of a limit switch with self-locking function Figure 1 .

[0015] Figure 3 A cross-section of a limit switch with self-locking function Figure 2 .

[0016] Figure 4 yes Figure 3 Enlarged view of point A in the middle.

[0017] Figure 5 Yes, yes Figure 3 Enlarged view of section B in the middle.

[0018] The components include: 1. Base; 11. Hole; 2. Switch assembly; 21. Push rod assembly; 211. Push rod; 3. Drive shaft; 31. Switching part; 311. First position; 312. Second position; 313. Third position; 314. Fourth position; 3131. First positioning groove; 3141. Second positioning groove; 4. Limiting post; 5. Elastic component; 6. Rotating rod; 61. First sliding wheel; 62. Second sliding wheel; 7. Cable entry unit; 71. Sealing ring; 711. Inclined surface; 72. Locking component; and 73. Transition component. Detailed Implementation

[0019] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0020] Example 1:

[0021] According to the appendix Figure 1 To the attached Figure 5 A limit switch with a self-locking function includes a base 1 having an accommodating space. A switch assembly 2 is disposed inside the base 1. The switch assembly 2 includes a moving contact and a stationary contact. When a push rod 211 pushes the switch assembly 2, it can move the moving contact, allowing the moving contact to engage with the stationary contact to achieve state switching of the switch assembly 2. For details of this technical feature, please refer to invention patent CN2014108575581, which specifically describes the engagement of the moving and stationary contacts on the switch assembly 2. A push rod assembly 21 is disposed at one end of the switch assembly 2. The push rod assembly 21 can be a single unit or composed of multiple components. A push rod 211 is disposed at the end of the push rod assembly 21 away from the switch assembly 2. The end of the push rod 211 away from the push rod assembly 21 engages with the push rod assembly 21. A switching part 31 connected to the drive shaft 3 is provided with a limiting post 4 on the side of the switching part 31 away from the push rod 211. The switching part 31 is provided with a first position 311, a second position 312, a third position 313 and a fourth position 314. When the push rod 211 is switched to the first position 311, the end of the limiting post 4 is connected to the first positioning groove 3131 of the third position 313. When the push rod 211 is switched to the second position 312, the end of the limiting post 4 is connected to the second positioning groove 3141 of the fourth position 314. The axial distance from the first position 311 to the drive shaft 3 is less than the axial distance from the second position 312 to the drive shaft 3. A rotating rod 6 is provided at one end of the base 1 and an inlet unit 7 is provided at the other end of the base 1. The rotating rod 6 is connected to the drive shaft 3.

[0022] In this embodiment, the drive shaft 3 has a switching part 31, which includes a first position 311 and a second position 312. The push rod 211 switches between the first position 311 and the second position 312 to switch the state of the switch assembly 2. That is, when the push rod 211 corresponds to the first position 311 or the second position 312, the switch assembly 2 can be in different states. In this embodiment, when the drive shaft 3 rotates, the positions of the first position 311 and the second position 312 relative to the push rod 211 can be switched to complete the switching.

[0023] In this embodiment, the switching unit 31 includes a third position 313 and a fourth position 314. When the push rod 211 corresponds to the first position 311, the limiting post 4 corresponds to the third position 313, thus fixing the position of the transmission shaft 3. When the push rod 211 corresponds to the second position 312, the limiting post 4 corresponds to the fourth position 314, thus fixing the position of the transmission shaft 3. When the push rod 211 corresponds to the first position 311 and the second position 312 respectively, the limiting post 4 can be positioned at the third position 313 or the fourth position 314 to fix the position of the transmission shaft 3 and achieve self-locking.

[0024] The third position 313 in this embodiment includes a first positioning groove 3131. When the push rod 211 corresponds to the first position 311, the end of the limiting post 4 abuts against the first positioning groove 3131 to restrict the rotation of the transmission shaft 3.

[0025] The fourth position 314 in this embodiment includes a second positioning groove 3141. When the push rod 211 corresponds to the second position 312, the end of the limiting post 4 abuts against the second positioning groove 3141 to restrict the rotation of the transmission shaft 3.

[0026] By setting the first positioning groove 3131 and the second positioning groove 3141, the end of the limiting post 4 can be positioned in the second positioning groove 3131 and the second positioning groove 3141 to complete the positioning, so that the transmission shaft 3 can complete the self-locking. The above structure is simple and the design is reasonable.

[0027] In this embodiment, both the first positioning groove 3131 and the second positioning groove 3141 are arc-shaped to facilitate smoother engagement with the limiting post 4 during state switching. The end of the limiting post 4 in this embodiment is spherical. The end of the push rod 211 in this embodiment can also be spherical to further facilitate smoother switching.

[0028] The end of the limiting post 4 away from the drive shaft 3 is connected to the elastic component 5, and the end of the elastic component 5 away from the limiting post 4 is connected to the inner surface of the base 1. In this embodiment, the elastic component 5 is disposed within the base 1 and applies force to the limiting post 4 so that the limiting post 4 abuts against the switching part 31. By applying force to the limiting post 4 through the elastic component 5, the limiting post 4 abuts against the switching part 31, ensuring that the state of the switching part 31 will not change under no external force, thus increasing the reliability of self-locking. In this embodiment, the elastic component 5 can be a spring.

[0029] A wavy arc is provided at the first position 311. The wavy arc increases the circumference of rotation within a certain space, so that it matches the circumference of the first positioning groove 3131.

[0030] The rotating rod 6 is provided with a first sliding wheel 61 and a second sliding wheel 62. In this embodiment, the rotating rod 6 is fixed on the transmission shaft 3, and the rotating rod 6 is provided with a first sliding wheel 61 and a second sliding wheel 62. When the rotating rod 6 rotates, it can drive the transmission shaft 3 to rotate, so that the position of the switching part 31 changes, thereby switching the switch assembly 2.

[0031] The incoming line unit 7 includes a sealing ring 71, a locking member 72, and a transition member 73. The base 1 has a hole 11, and the sealing ring 71 is disposed within the hole 11. The end of the sealing ring 71 has a bevel 711, and the end face of the hole 11 mates with the bevel 711. The locking member 72 is threaded into the hole 11 and presses against the sealing ring 71. The cable passes through the locking member 72 and the sealing ring 71 and is connected to the switch assembly 2. A transition member 73 is provided between the locking member 72 and the sealing ring 71. When the locking member 72 presses against the sealing ring 71, it deforms the sealing ring 71 to press against the cable, thus fixing the cable and preventing it from loosening. Furthermore, after the sealing ring 71 presses against the cable, it ensures a tight seal, guaranteeing waterproofing and dustproofing.

[0032] The roughness of the contact surface between the transition member 73 and the sealing ring 71 is greater than the roughness of the contact surface between the transition member 73 and the locking member 72. This prevents the locking member 72 from directly contacting the sealing ring 71 and prevents the sealing ring 71 from being twisted and deformed when the locking member 72 is tightened, thus affecting the sealing performance.

[0033] The locking element 72 is made of plastic, which is less prone to rusting and stripping than metal, and is also less expensive than metal.

[0034] The working process of this invention is as follows: When the first sliding wheel 61 and the second sliding wheel 62 provided on the rotating rod 6 drive the rotating rod 6 to rotate, the rotating rod 6 can drive the transmission shaft 3 to rotate, so that the position of the switching part 31 changes, the push rod 211 is aligned with the first position 311, the limiting post 4 is aligned with the third position 313, and the position of the transmission shaft 3 is relatively fixed. When the push rod 211 is aligned with the second position 312, the limiting post 4 is aligned with the fourth position 314, and the position of the transmission shaft 3 is relatively fixed. When the push rod 211 is aligned with the first position 311 and the second position 312 respectively, the limiting post 4 can be positioned in the third position 313 or the fourth position 314, so that the position of the transmission shaft 3 is relatively fixed, so as to complete self-locking. At the same time, the switch assembly 2 is pushed by the push rod 211. When the push rod 211 pushes the switch assembly 2, it can drive the moving contact to move, so that the moving contact and the stationary contact can cooperate, so as to realize the state switching of the switch assembly 2.

[0035] The above description is only a preferred embodiment of the present invention. It should be noted that those skilled in the art can make several changes and improvements without departing from the overall concept of the present invention, and these should also be considered within the scope of protection of the present invention.

Claims

1. A travel switch with self-locking function, comprising a base (1), characterized in that, The base (1) is internally provided with a switch assembly (2), one end of the switch assembly (2) is provided with a push rod assembly (21), the push rod assembly (21) is provided with a push rod (211) away from one end of the switch assembly (2), the push rod (211) is connected with a switching part (31) of a transmission shaft (3) at one end away from the push rod assembly (21), the switching part (31) of the transmission shaft (3) is provided with a limiting column (4) away from one side of the push rod (211), the switching part (31) is provided with a first position (311), a second position (312), a third position (313) and a fourth position (314), when the push rod (211) is switched to the first position (311), the end of the limiting column (4) is connected to the first positioning groove (3131) at the third position (313), when the push rod (211) is switched to the second position (312), the end of the limiting column (4) is connected to the second positioning groove (3141) at the fourth position (314), the distance from the first position (311) to the axis of the transmission shaft (3) is less than the distance from the second position (312) to the axis of the transmission shaft (3), one end of the base (1) is provided with a rotating rod (6), the other end of the base (1) is provided with a wire inlet unit (7), and the rotating rod (6) is connected with the transmission shaft (3); Through the arrangement of the first positioning groove (3131) and the second positioning groove (3141), the end of the limiting column (4) can be positioned in the first positioning groove (3131) and the second positioning groove (3141), so as to complete positioning and make the transmission shaft (3) complete self-locking; The first position (311) is provided with a wave arc line, and the arrangement of the wave arc line increases the circumference of rotation, so that it matches the circumference of the first positioning groove (3131).

2. The travel switch with self-locking function according to claim 1, characterized in that, The end of the limiting column (4) away from the transmission shaft (3) is connected with an elastic component (5), and the end of the elastic component (5) away from the limiting column (4) is connected with the inner surface of the base (1).

3. The travel switch with self-locking function according to claim 1, characterized in that, The rotating rod (6) is provided with a first sliding wheel (61) and a second sliding wheel (62).

4. The travel switch with self-locking function according to claim 1, characterized in that, The wire inlet unit (7) comprises a sealing ring (71), a locking piece (72) and a transition piece (73), the base (1) is provided with a hole (11), the sealing ring (71) is arranged in the hole (11), the locking piece (72) is threadedly connected with the hole (11) and presses the sealing ring (71), a cable passes through the locking piece (72) and the sealing ring (71) and is connected with the switch assembly (2), and the transition piece (73) is arranged between the locking piece (72) and the sealing ring (71).

5. The travel switch with self-locking function according to claim 4, characterized in that, The roughness of the contact surface between the transition piece (73) and the sealing ring (71) is greater than the roughness of the contact surface between the transition piece (73) and the locking piece (72).

6. The travel switch with self-locking function according to claim 5, characterized in that, The locking piece (72) is made of plastic material.

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