A high-precision limit switch

Abstract

This invention discloses a high-precision limit switch, comprising a housing and an input shaft, an encoder, a transmission assembly, a limit drive assembly, and a limit receiver assembly disposed within the housing. One end of the input shaft extends out of the housing, and the other end extends into the housing and is connected to the encoder and the transmission assembly respectively. The limit drive assembly includes a lead screw, a guide rod, an internal threaded sleeve, and a contact rod. The lead screw is rotatably connected to the housing and connected to the transmission assembly for transmission. The guide rod is fixed parallel to one side of the lead screw. The internal threaded sleeve is fitted onto the lead screw, and a guide sleeve fitted onto the guide rod is provided on one side of the internal threaded sleeve. The contact rod is fixed onto the internal threaded sleeve. The limit receiver assembly includes a splined slide shaft and several limit switches. The several limit switches are all fitted onto the splined slide shaft, and each of the several limit switches is connected to an axial position adjustment device. The contact rod engages with the contacts of the limit switches. This high-precision limit switch has a multi-level limit function, is easy to install and use, and allows adjustment of each limit level.

Description

Technical Field

[0001] This invention relates to the field of limit switch technology, and more specifically to a high-precision limit switch. Background Technology

[0002] Existing multi-level limit switches for lifting devices typically involve installing contact or inductive limit switches at each height position where the lifting device needs to stop. However, this method requires precise installation of the limit switches at each height, which is difficult and makes subsequent maintenance and adjustment cumbersome. Therefore, a high-precision multi-level limit switch that is easy to install, use, and maintain is needed. Summary of the Invention

[0003] To address the shortcomings of existing technologies, this invention provides a high-precision limit switch. This high-precision limit switch has multi-level limit functions, is easy to install, use, and maintain, and can also quickly adjust each level of the limit.

[0004] To achieve the above objectives, the present invention provides the following technical solution:

[0005] A high-precision limit switch includes a housing and an input shaft, a transmission assembly, an encoder, a limit drive assembly, and a limit receiver assembly disposed within the housing. One end of the input shaft extends out of the housing, and the other end extends into the housing and is connected to the encoder and the transmission assembly respectively. The limit drive assembly includes a lead screw, a guide rod, an internal threaded sleeve, and a contact rod. The lead screw is rotatably connected to the housing and connected to the transmission assembly for transmission. The guide rod is fixed parallel to one side of the lead screw. The internal threaded sleeve is threaded onto the lead screw, and a guide sleeve is provided on one side of the internal threaded sleeve. The guide sleeve is fitted onto the guide rod. The contact rod is fixed to the internal threaded sleeve. The limit receiver assembly includes a splined slide shaft and several limit switches. The splined slide shaft is fixed parallel to one side of the lead screw. Several limit switches are sequentially fitted onto the splined slide shaft, and each of the limit switches is connected to an axial position adjustment device. Each contact rod can contact and engage with the contacts of the several limit switches.

[0006] Furthermore, the axial position adjustment device includes a rack, an adjusting gear, a connecting shaft, and a knob. The rack is fixedly connected to a limit switch and is parallel to a spline slide shaft. The connecting shaft is rotatably connected to the housing, and one end of the connecting shaft extends out of the housing and is connected to the knob. The adjusting gear is fixed on the connecting shaft and meshes with the rack. A locking device is also provided outside the housing to lock the connecting shaft and prevent it from rotating.

[0007] Furthermore, an external thread section is provided between the end of the connecting shaft extending out of the housing and the knob. The locking device is a locking sleeve with an internal thread inside. The locking sleeve is threadedly connected to the external thread section, and the end face of the locking sleeve can press against the outer side of the housing.

[0008] Furthermore, an annular scale value is provided on the outer side of the housing located outside the connecting shaft, and a marking arrow is provided on the outward-facing end face of the knob, with the marking arrow pointing towards the annular scale value.

[0009] Furthermore, an indicator bar is connected to the end face of the knob facing the housing, and an indicator line is provided on the indicator bar, which is in conjunction with the annular scale value.

[0010] Furthermore, the annular sides of both the knob and the locking sleeve are provided with several anti-slip stripes.

[0011] Furthermore, the transmission assembly includes a driving gear and a driven gear. The driving gear is fixedly connected to the input shaft, and the driven gear is fixedly connected to the lead screw. The driving gear and the driven gear mesh.

[0012] Compared with the prior art, the beneficial effects of the present invention are:

[0013] (1) This invention sets up a housing, an input shaft, a transmission assembly, a lead screw, a guide rod, an internal threaded sleeve and a contact rod, a splined sliding shaft and several limit switches. By connecting the input shaft to the drive mechanism (e.g., a motor) of the lifting device, the input shaft is driven to rotate. The transmission assembly then drives the lead screw to rotate, and the lead screw drives the internal threaded sleeve and the contact rod to move axially. This causes the contact rod to contact and engage with the contacts of several limit switches in sequence. The limit switches are triggered and then transmit signals to the control system of the lifting device. The control system receives the signals and reacts to control the drive mechanism to stop at each limit height position, thus achieving the function of multi-level limit. There is no need to install limit switches at the limit height, making installation and use more convenient. In case of problems, only the high-precision limit switches need to be repaired, making maintenance convenient.

[0014] (2) The present invention also connects several limit switches to an axial position adjustment device, so that the axial position of the limit switch on the spline slide can be adjusted individually through the axial position adjustment device, thereby quickly changing the height position of each limit switch; and the axial position adjustment device is set as a rack, adjusting gear, connecting shaft and knob, so that when adjusting, only the knob needs to be turned, making the adjustment quick and convenient.

[0015] (3) The present invention also includes an encoder inside the housing. By connecting the encoder to the input shaft, the encoder can be used to collect the rotation data of the input shaft in real time, transmit it to the control system for identification and judgment, and display the power output data of the drive mechanism and the current running height data. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort, wherein:

[0017] Figure 1 A schematic diagram of the structure of a high-precision limit switch Figure 1 ;

[0018] Figure 2 A schematic diagram of the structure of a high-precision limit switch Figure 2 ;

[0019] Figure 3 This is a partial schematic diagram of the outer side of the housing located at the connecting shaft;

[0020] Figure 4 for Figure 2 Enlarged view of point A in the middle.

[0021] The markings in the diagram are as follows: 1. Housing; 2. Input shaft; 3. Encoder; 4. Drive gear; 5. Driven gear; 6. Lead screw; 7. Guide rod; 8. Guide sleeve; 9. Internal threaded sleeve; 10. Contact rod; 11. Splined slide shaft; 12. Adjusting gear; 13. Limit switch; 14. Connecting shaft; 15. Rack; 16. Locking sleeve; 17. Knob; 18. External threaded section; 19. Indicator bar; 20. Marking arrow; 21. Indicator line; 22. Circular scale value. Detailed Implementation

[0022] In the description of this invention, it should be noted that the directional terms such as "center", "horizontal (X)", "longitudinal (Y)", "vertical (Z)", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", and "counterclockwise" indicate the orientation and positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. They should not be construed as limiting the specific protection scope of this invention.

[0023] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features. Thus, the use of "first" and "second" to define a feature may explicitly or implicitly include one or more of that feature. In the description of this invention, "several" or "a number" means two or more, unless otherwise explicitly specified.

[0024] A high-precision limit switch, such as Figure 1-4 As shown, the device includes a housing 1 and an input shaft 2, a transmission assembly, a limit drive assembly, and a limit receiving assembly disposed within the housing 1. One end of the input shaft 2 extends out of the housing 1, and the other end extends into the housing 1 and connects to the transmission assembly. The limit drive assembly includes a lead screw 6, a guide rod 7, an internal threaded sleeve 9, and a contact rod 10. The lead screw 6 is rotatably connected to the housing 1 and is connected to the transmission assembly for transmission. The guide rod 7 is fixed parallel to one side of the lead screw 6. The internal threaded sleeve 9 is threaded onto the lead screw 6, and a guide sleeve 8 is provided on one side of the internal threaded sleeve 9. The guide sleeve 8 is fitted onto the guide rod 7. The contact rod 10 is fixed to the internal threaded sleeve 9. The limit receiving assembly includes a splined slide shaft 11 and several limit switches 13. The splined slide shaft 11 is fixed parallel to one side of the lead screw 6. Several limit switches 13 are sequentially fitted onto the splined slide shaft 11, and each of the limit switches 13 is connected to an axial position adjustment device. Each contact rod 10 can contact and cooperate with the contacts of the several limit switches 13.

[0025] This invention comprises a housing 1, an input shaft 2, a transmission assembly, a lead screw 6, a guide rod 7, an internal threaded sleeve 9, a contact rod 10, a splined sliding shaft 11, and several limit switches 13. The input shaft 2 is connected to the drive mechanism (e.g., a motor) of the lifting device, causing the input shaft 2 to rotate. The transmission assembly then drives the lead screw 6 to rotate, which in turn drives the internal threaded sleeve 9 and the contact rod 10 to move axially. This causes the contact rod 10 to sequentially engage with the contacts of the several limit switches 13. The limit switches 13 are triggered and transmit signals to the control system of the lifting device. The control system receives the signals and reacts by stopping the drive mechanism at various limit height positions, achieving a multi-level limit function. This eliminates the need to install limit switches 13 at the limit heights, making installation and use convenient. Furthermore, in case of problems, only the high-precision limit switches need to be repaired, making maintenance easy.

[0026] Furthermore, the present invention connects several limit switches 13 to the axial position adjustment device of the shaft 14, so that the axial position of the limit switch 13 on the spline slide shaft 11 can be adjusted individually through the axial position adjustment device, thereby quickly changing the height position of each limit switch, making the adjustment fast and convenient.

[0027] In this embodiment, the preferred embodiment is as follows: Figure 1-2As shown, the axial position adjustment device includes a rack 15, an adjusting gear 12, a connecting shaft 14, and a knob 17. The rack 15 is fixedly connected to the limit switch 13 and is parallel to the spline slide shaft 11. The connecting shaft 14 is rotatably connected to the housing 1 and one end of the connecting shaft 14 extends out of the housing 1 and is connected to the knob 17. The adjusting gear 12 is fixed on the connecting shaft 14 and meshes with the rack 15. A locking device is also provided outside the housing 1, which can lock the connecting shaft 14 to prevent the connecting shaft 14 from rotating.

[0028] Specifically, when adjusting the position of the limit switch 13, first open the locking device so that the locking device no longer locks the connecting shaft 14, then turn the knob 17 to drive the connecting shaft 14 to rotate, which in turn drives the adjusting gear 12 to rotate. The adjusting gear 12 then drives the rack 15 to move, so that the limit switch 13 moves axially on the spline slide shaft 11, thereby achieving the adjustment. After the adjustment is completed, the connecting shaft 14 can be locked by the locking device.

[0029] In this embodiment, the preferred embodiment is as follows: Figure 4 As shown, an external thread section 18 is provided between the end of the connecting shaft 14 extending out of the housing 1 and the knob 17. The locking device is a locking sleeve 16, which has an internal thread. The locking sleeve 16 is threadedly connected to the external thread section 18, and the end face of the locking sleeve 16 can press against the outer side of the housing 1.

[0030] Specifically, when it is necessary to adjust the axial position of the limit switch 13 on the spline slide shaft 11, loosen the locking sleeve 16 so that the locking sleeve 16 is no longer pressed against the housing 1. At this time, the connecting shaft 14 is no longer locked. The connecting shaft 14 can be rotated by turning the knob 17. The limit switch 13 can be adjusted by adjusting the gear 12 and the rack 15. After the adjustment is completed, tighten the locking sleeve 16 so that the locking sleeve 16 presses against the housing 1 and locks the connecting shaft 14 to ensure that the position of the limit switch 13 is fixed.

[0031] In this embodiment, the preferred embodiment is as follows: Figure 3 As shown, an annular scale value 22 is provided on the outer side of the housing 1, located outside the connecting shaft 14. A marking arrow 20 is provided on the outward-facing end face of the knob 17, with the marking arrow 20 pointing towards the annular scale value 22. By providing the marking arrow 20, the operator can easily check the rotation angle of the knob 17 through the marking arrow 20 and the annular scale value 22, thereby accurately adjusting the axial movement value of the limit switch 13.

[0032] In this embodiment, the preferred embodiment is as follows: Figure 3-4As shown, the knob 17 is connected to an indicator strip 19 on the end face facing the housing 1. An indicator line 21 is provided on the indicator strip 19. The indicator line 21 is aligned with the marked arrow 20 and cooperates with the annular scale value 22. By setting the indicator strip 19 and the indicator line 21, and cooperating with the marked arrow 20, it is easier for the operator to see the relative position between the marked arrow 20 and the annular scale value 22, which facilitates precise adjustment by the operator.

[0033] In this embodiment, the preferred embodiment is as follows: Figure 4 As shown, the annular sides of both the knob 17 and the locking sleeve 16 are provided with several anti-slip stripes to prevent slipping and facilitate the application of force to rotate the knob 17 and the locking sleeve 16.

[0034] In this embodiment, the preferred embodiment is as follows: Figure 1-2 As shown, the transmission assembly includes a driving gear 4 and a driven gear 5. The driving gear 4 is fixedly connected to the input shaft 2, and the driven gear 5 is fixedly connected to the lead screw 6. The driving gear 4 and the driven gear 5 mesh, thereby transmitting the torque of the input shaft 2 to the lead screw 6 to drive the lead screw 6 to rotate.

[0035] In this embodiment, the preferred embodiment is as follows: Figure 1 As shown, an encoder 3 is also provided inside the housing 1. The encoder 3 is connected to the input shaft 2, so that the rotation data of the input shaft 2 can be collected in real time through the encoder 3 and transmitted to the control system for identification and judgment, and the power output data of the drive mechanism and the current running height data can be displayed.

[0036] The above description is merely a preferred embodiment of the present invention. The scope of protection of the present invention is not limited to the above embodiments. All technical solutions falling within the scope of the present invention's concept are within the scope of protection of the present invention. It should be noted that for those skilled in the art, any improvements and modifications made without departing from the principles of the present invention should also be considered within the scope of protection of the present invention.

Claims

1. A high-precision limit switch, characterized in that: The device includes a housing and an input shaft, encoder, transmission assembly, limit drive assembly, and limit receiver assembly disposed within the housing. One end of the input shaft extends out of the housing, and the other end extends into the housing and is connected to the encoder and transmission assembly respectively. The limit drive assembly includes a lead screw, a guide rod, an internal threaded sleeve, and a contact rod. The lead screw is rotatably connected to the housing and is connected to the transmission assembly for transmission. The guide rod is fixed parallel to one side of the lead screw. The internal threaded sleeve is threaded onto the lead screw, and a guide sleeve is provided on one side of the internal threaded sleeve. The guide sleeve is fitted onto the guide rod. The contact rod is fixed to the internal threaded sleeve. The limit receiver assembly includes a spline slide shaft and several limit switches. The spline slide shaft is fixed parallel to one side of the lead screw. Several limit switches are sequentially fitted onto the spline slide shaft, and each limit switch is connected to a corresponding axial position adjustment device. The contact rods can contact and cooperate with the contacts of the several limit switches. The axial position adjustment device includes a rack, an adjusting gear, a connecting shaft, and a knob. The rack is fixedly connected to a limit switch and is parallel to a spline slide shaft. The connecting shaft is rotatably connected to the housing, and one end of the connecting shaft extends out of the housing and is connected to the knob. The adjusting gear is fixed on the connecting shaft and meshes with the rack. A locking device is also provided outside the housing to lock the connecting shaft and prevent it from rotating.

2. The high-precision limit switch according to claim 1, characterized in that: The connecting shaft has an external thread section between its end extending out of the housing and the knob. The locking device is a locking sleeve with an internal thread. The locking sleeve is threaded onto the external thread section, and the end face of the locking sleeve can press against the outer side of the housing.

3. A high-precision limit switch according to claim 2, characterized in that: An annular scale value is provided on the outer side of the housing, located outside the connecting shaft, and a marking arrow is provided on the outward-facing end face of the knob, with the marking arrow pointing towards the annular scale value.

4. A high-precision limit switch according to claim 3, characterized in that: The knob is connected to an indicator bar on the end face facing the housing. The indicator bar has indicator lines that correspond to the annular scale values.

5. A high-precision limit switch according to claim 4, characterized in that: Both the knob and the locking sleeve have several anti-slip stripes on their annular sides.

6. A high-precision limit switch according to claim 1, characterized in that: The transmission assembly includes a driving gear and a driven gear. The driving gear is fixedly connected to the input shaft, and the driven gear is fixedly connected to the lead screw. The driving gear and the driven gear mesh.

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