Proximity sensor

Abstract

Provided in the present disclosure is a proximity sensor, comprising: a tubular housing, provided with an axially-through first cavity, the tubular housing comprising a head end and a tail end opposite to each other in the axial direction; a tail plug, internally provided with a second cavity, one axial end of the tail plug being connected to the tail end of the tubular housing, and the other axial end of the tail plug being provided with a first wire outlet hole communicated with the second cavity; and an electrical assembly, comprising a circuit board and a resistance adjustment device provided on the circuit board, wherein a portion of the circuit board is accommodated in the first cavity, the other portion of the circuit board extends from the tail end into the second cavity, the resistance adjustment device is at least partially located in the second cavity, a cable is connected to the circuit board, and the cable passes through the first wire outlet hole and exits the second cavity. The proximity sensor provided by the present disclosure enables improvement of product consistency and flexibility.

Description

A proximity sensor

[0001] Cross-reference of related applications

[0002] This application claims priority to Chinese Patent Application No. 202510127665.7, filed in China on January 27, 2025, the entire contents of which are incorporated herein by reference. Technical Field

[0003] This disclosure relates to the field of proximity sensor technology, and more particularly to a proximity sensor. Background Technology

[0004] Inductive proximity sensors are based on the principle of electromagnetic induction. They detect the distance between a target metal object and the proximity sensor, convert the distance signal into an electrical signal, and then convert it into a control signal. They do not produce mechanical wear and have advantages such as high switching frequency and high precision. They are widely used in industries such as machinery manufacturing, electronics, automobiles, food, and plastics. Summary of the Invention

[0005] To address at least one of the technical problems in the prior art described above, this disclosure provides a proximity sensor.

[0006] The technical solutions provided in this disclosure are as follows:

[0007] This disclosure provides a proximity sensor, including:

[0008] A tubular shell having an axially penetrating first cavity, the tubular shell including a head end and a tail end opposite each other along the axial direction;

[0009] A tail plug, having a second cavity inside, has one axial end connected to the tail end of the tube shell, and the other axial end of the tail plug having a first outlet hole communicating with the second cavity; and

[0010] An electrical component includes a circuit board and a resistor adjustment device disposed on the circuit board. A portion of the circuit board is housed in a first cavity, and another portion extends from the tail end into a second cavity. The resistor adjustment device is at least partially located in the second cavity. A cable is connected to the circuit board and passes through the first outlet hole and exits the second cavity.

[0011] For example, the tail plug includes a first connecting portion for connecting to the tail end, the first connecting portion being inserted into the tail end, and the first connecting portion and the tail end being interference-fitted.

[0012] For example, at least one of the circumferential outer surface of the first connecting part and the axial inner surface of the tail end is provided with a sealing protrusion structure, and the first connecting part is interference-fitted with the tail end through the sealing protrusion structure.

[0013] For example, the sealing protrusion structure includes at least one sealing protrusion ring disposed circumferentially around the first connection portion.

[0014] For example, at least one radial groove or radial hole is provided on the circumferential outer surface of the first connecting part, the first connecting part and the tail end are fixed by filler adhesive, and at least part of the filler adhesive is located in the radial groove or radial hole.

[0015] For example, the electrical component further includes a light-emitting element disposed on the circuit board; the tail plug is configured as a lampshade structure, which includes a light-transmitting substrate, the substrate including a first connecting portion connected to the tail end and a light-emitting portion for emitting light, wherein the light-emitting portion is located on the side of the first connecting portion axially away from the tail end, and the light-emitting portion circumferentially surrounds the light-emitting element.

[0016] For example, the substrate material includes a transparent substrate material and scattering particle material doped in the transparent substrate material, wherein the scattering particle material includes titanium dioxide.

[0017] For example, the light-emitting portion circumferentially surrounds the rheostat, and in the axial direction of the housing, the width of the light-emitting portion is greater than or equal to the width of the rheostat; and the difference between the maximum diameter of the light-emitting portion and the maximum diameter of the housing is less than or equal to a first threshold.

[0018] For example, at least one of the circumferential inner surface and circumferential outer surface of the tail plug is provided with a reflective structure, the reflective structure being directly opposite the position of the light-emitting element in the axial direction of the tube shell, and the reflective structure being configured to reflect at least part of the light emitted by the light-emitting element to the light-emitting portion.

[0019] For example, the reflective structure includes a reflective section that is axially inclined relative to the casing, the reflective section being inclined at an angle of 30 to 60° relative to the casing.

[0020] For example, the light-emitting part includes a light-emitting surface and a light-concentrating surface arranged adjacent to each other. The light-emitting surface is an annular arc surface, and the light-concentrating surface is an annular oblique surface. The light-concentrating surface is configured to converge at least a portion of the light emitted by the light-emitting element.

[0021] For example, at least one of the circumferential inner surface and circumferential outer surface of the tail plug is provided with a prism structure, the prism structure being configured to diffuse the light emitted from the light-emitting element.

[0022] For example, the prism structure includes an array of prisms or pyramids.

[0023] For example, the prism structure includes multiple sides, and at least some of the sides are configured to reflect light emitted from the light-emitting element to the light-emitting portion.

[0024] For example, the first outlet has an outer port away from the second cavity and an inner port close to the second cavity, and the first outlet is configured to gradually narrow from the outer port to the inner port.

[0025] For example, the circumferential inner wall of the inner port is constructed as an edge-like structure or a planar structure.

[0026] For example, the proximity sensor further includes a cable protective sleeve, which includes a sleeve portion and a flexible protective portion. The sleeve portion is fitted onto the end of the tail plug that has the first cable outlet hole, and the flexible protective portion has a second cable outlet hole. The cable that passes through the first cable outlet hole is inserted into the second cable outlet hole.

[0027] For example, the flexible protective part has a plurality of openings on its peripheral surface, and the plurality of openings are arranged sequentially along the axial direction of the cable to form a plurality of opening units. Each opening unit includes at least one opening arranged along the circumferential direction of the cable, and the openings in two adjacent opening units are arranged alternately.

[0028] For example, the opening has a circumferential dimension of 4±1mm and an axial dimension of 0.6±0.2mm, and the spacing between two adjacent opening units in the axial direction of the cable is 1±0.5mm.

[0029] For example, the tail plug includes a second connecting portion for connecting with the sleeve portion. The outer circumferential surface of the second connecting portion is provided with a concave-convex structure, and the inner circumferential surface of the sleeve portion is provided with a concave-convex fitting structure. The sleeve portion is sleeved on the second connecting portion, and the concave-convex structure cooperates with the concave-convex fitting structure to engage and fix the sleeve portion and the second connecting portion.

[0030] For example, the height of the recess or protrusion of the concave-convex structure relative to the axial outer surface of the second connecting part is 0.2 to 0.5 mm.

[0031] For example, the tail plug is configured as a lampshade structure, which includes a light-emitting portion, wherein the second connecting portion is located on the side of the light-emitting portion away from the tube shell, and the difference between the maximum diameter of the sleeve portion and the maximum diameter of the light-emitting portion is less than or equal to a second threshold.

[0032] For example, the cable located in the second cavity includes an exposed conductor area and a conductor wrapping area. The exposed conductor area is electrically connected to the circuit board, and the conductor wrapping area has a length greater than or equal to 3 mm along the extension direction of the cable.

[0033] The beneficial effects of the embodiments disclosed herein are as follows:

[0034] The proximity sensor provided in this disclosure includes a housing, a tail plug, and an electrical assembly. The housing includes a head end and a tail end that are axially opposite each other. The electrical assembly includes a circuit board and a resistance adjustment device disposed on the circuit board. The tail plug is connected to the tail end of the housing, and a portion of the circuit board is placed in a first cavity of the housing, while another portion of the circuit board extends into a second cavity of the tail plug. The resistance adjustment device is at least partially located in the second cavity of the tail plug. In other words, the tail plug is configured such that the second cavity can accommodate the resistance adjustment assembly, so that the resistance adjustment device is external to the housing. Thus, when it is necessary to adjust the resistance or potential of the resistance adjustment device, only the tail plug needs to be removed from the housing, without disassembling the housing and repeating the test. Furthermore, after the entire proximity sensor is assembled, if the inductance value changes, the detachable tail plug can be removed for re-adjustment, improving the consistency and flexibility of the product. Attached Figure Description

[0035] Figure 1 shows an exploded view of the proximity sensor provided in the embodiments of this disclosure;

[0036] Figure 2 shows one of the front views of the proximity sensor provided in the embodiments of this disclosure;

[0037] Figure 3 shows a schematic diagram of the cross section along direction AA in Figure 2;

[0038] Figure 4 shows one of the three-dimensional structural schematic diagrams of the tail plug of the proximity sensor provided in the embodiments of this disclosure;

[0039] Figure 5 shows one of the front views of the tail plug of the proximity sensor provided in the embodiments of this disclosure;

[0040] Figure 6 shows a schematic diagram of the cross section along the BB direction in Figure 5;

[0041] Figure 7 shows a second three-dimensional structural schematic diagram of the tail plug of the proximity sensor provided in the embodiments of this disclosure;

[0042] Figure 8 shows a second front view of the tail plug of the proximity sensor provided in an embodiment of this disclosure;

[0043] Figure 9 shows a schematic diagram of the cross section in the CC direction of Figure 8;

[0044] Figure 10 shows a third front view of the tail plug of the proximity sensor provided in an embodiment of this disclosure;

[0045] Figure 11 shows a schematic diagram of the cross-section in the DD direction of Figure 10;

[0046] Figure 12 shows a side view of Figure 10;

[0047] Figure 13 shows a second front view of the proximity sensor provided in an embodiment of this disclosure, wherein the cables are not shown.

[0048] Figure 14 shows a schematic diagram of the cross section along the EE direction in Figure 13;

[0049] Figure 15 shows a third three-dimensional structural schematic diagram of the tail plug in the proximity sensor provided in this embodiment of the present disclosure;

[0050] Figure 16 shows one of the schematic diagrams of a prism structure;

[0051] Figure 17 shows the second schematic diagram of the prism structure;

[0052] Figure 18 shows a three-dimensional structural diagram of the cable protective sleeve in the proximity sensor provided in the disclosed embodiment;

[0053] Figure 19 shows a front view of the cable protective sleeve in the proximity sensor provided in an embodiment of this disclosure;

[0054] Figure 20 shows a schematic diagram of the cross-sectional structure in the FF direction of Figure 19;

[0055] Figure 21 shows a schematic diagram of the connection structure between the tail plug and the cable protective sleeve in the proximity sensor provided in an embodiment of this disclosure;

[0056] Figure 22 shows one of the structural schematic diagrams of the first wire outlet hole in the proximity sensor provided in the embodiments of this disclosure;

[0057] Figure 23 shows a second schematic diagram of the structure of the first wire outlet hole in the proximity sensor provided in the embodiment of this disclosure;

[0058] Figure 24 shows a third schematic diagram of the structure of the first wire outlet hole in the proximity sensor provided in this embodiment of the present disclosure;

[0059] Figure 25 shows a fourth schematic diagram of the structure of the first wire outlet hole in the proximity sensor provided in the embodiments of this disclosure. Detailed Implementation

[0060] To make the objectives, technical solutions, and advantages of the embodiments of this disclosure clearer, the technical solutions of the embodiments of this disclosure will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this disclosure. All other embodiments obtained by those skilled in the art based on the described embodiments of this disclosure without creative effort are within the scope of protection of this disclosure.

[0061] Unless otherwise defined, the technical or scientific terms used in this disclosure shall have the ordinary meaning understood by one of ordinary skill in the art to which this disclosure pertains. The terms “first,” “second,” and similar terms used in this disclosure do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Similarly, the terms “an,” “a,” or “the,” and similar terms do not indicate a quantity limitation, but rather indicate the presence of at least one. The terms “including,” “comprising,” or “containing,” and similar terms mean that the element or object preceding the word encompasses the elements or objects listed following the word and their equivalents, without excluding other elements or objects. The terms “connected,” “linked,” or similar terms are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. The terms “upper,” “lower,” “left,” and “right,” etc., are used only to indicate relative positional relationships, and these relative positional relationships may change accordingly when the absolute position of the described objects changes.

[0062] The features such as "parallel," "perpendicular," and "identical" used in the embodiments of this disclosure include features in the strict sense of "parallel," "perpendicular," and "identical," as well as cases where "approximately parallel," "approximately perpendicular," and "approximately identical" include certain tolerances. Taking into account the measurement and the tolerances associated with the measurement of a specific quantity (e.g., limitations of the measurement system), they represent the acceptable deviation range for a specific value as determined by a person skilled in the art. For example, "approximately" can mean within one or more standard deviations, or within 3% or 5% of said value.

[0063] Furthermore, throughout this document, unless otherwise defined, the terms “substantially,” “essentially,” “approximately,” and “about” are used to describe and explain small variations. When used with an event or situation, these terms can cover situations where the event or situation occurs precisely or approximately. For example, when used with a numerical value, these terms can include a range of variation of the numerical value less than or equal to 10%, such as less than or equal to ±5%, less than or equal to ±4%, less than or equal to ±3%, less than or equal to ±2%, less than or equal to ±1%, less than or equal to ±0.5%, less than or equal to ±0.1%, or less than or equal to ±0.05%. The term “substantially coplanar” can refer to two surfaces arranged along the same plane within a micrometer range, for example, within 40 μm, 30 μm, 20 μm, 10 μm, or 1 μm.

[0064] Before describing the proximity sensor provided in the embodiments of this disclosure, the related technologies will be described as follows:

[0065] Inductive proximity sensors are an important type of proximity switch, mainly used for sensing metallic targets. They utilize the electromagnetic field generated when a conductor approaches the coil of the proximity sensor, inducing eddy currents inside the conductor. The reaction of these eddy currents on the electromagnetic system of the proximity sensor changes the electromagnetic parameters of the sensor, thereby identifying the approach and departure of the conductor and controlling the switch to turn on and off.

[0066] The proximity sensor mainly consists of components such as a head plug, electrical components, a housing, and a tail plug. The head plug is installed at one axial end of the housing, and the tail plug is installed at the other axial end. The electrical components include a circuit board and adjustable resistors. To ensure the measurement stability of the proximity sensor, the internal cavities of each component are filled with potting compound to tightly bond the components together.

[0067] However, proximity sensors in related technologies suffer from problems such as poor product consistency, low debugging accuracy and efficiency, and insufficient flexibility.

[0068] The applicant has discovered through research that one of the reasons for the above-mentioned problems is that, since the adjustable device is built into the housing, adjusting the adjustable device requires repeatedly disassembling the housing and conducting tests, which affects product consistency, debugging accuracy, and efficiency. Furthermore, the assembly process of the proximity sensor involves first fixing the head plug to the housing with instant adhesive, then applying glue, and finally assembling the tail plug onto the housing. As a result, since the adjustable device is built into the housing, if the inductance value changes, the adjustable device cannot be adjusted again after the glue application is completed, leading to insufficient flexibility.

[0069] To address the aforementioned problems, this disclosure provides a proximity sensor. As shown in Figures 1 to 3, the proximity sensor in this disclosure includes:

[0070] The shell 100 has an axially penetrating first cavity 110, and the shell 100 includes a head end 100A and a tail end 100B that are axially opposite each other.

[0071] A tail plug 200 has a second cavity 210 inside. One axial end of the tail plug 200 is connected to the tail end 100B of the tube shell 100, and the other axial end of the tail plug 200 is provided with a first outlet hole 220 communicating with the second cavity 210.

[0072] Electrical component 300 includes circuit board 310 and adjustable resistor 320 disposed on circuit board 310. A portion of circuit board 310 is housed in first cavity 110, and another portion extends from tail end 100B into second cavity 210. Adjustable resistor 320 is at least partially located in second cavity 210. Cable 330 is connected to circuit board 310 and passes through first outlet hole 220 to exit second cavity 210.

[0073] In the proximity sensor provided in this embodiment, a portion of the circuit board 310 is placed in the first cavity 110 of the housing 100, and another portion of the circuit board 310 extends into the second cavity 210 of the tail plug 200. The adjustable resistor 320 is at least partially located in the second cavity 210 of the tail plug 200. In other words, the tail plug 200 is configured such that the second cavity 210 can accommodate the adjustable resistor assembly, such that the adjustable resistor 320 is external to the housing 100.

[0074] In this way, when it is necessary to adjust the resistance or potential of the adjustable device 320, only the tail plug 200 needs to be removed from the housing 100, without having to disassemble the housing 100 and perform testing, which improves the consistency, debugging accuracy and efficiency of the product; and after the entire proximity sensor is assembled, if the inductance value changes, only the tail plug 200 needs to be removed for re-adjustment, which improves the flexibility of the product.

[0075] It should be noted that in the above solution, the adjustable resistor 320 is external to the housing 100 and housed in the second cavity 210 of the tail plug 200. The tail plug 200 needs sufficient space to accommodate the circuit board 310 and the adjustable resistor 320, among other components. For example, the diameter of the second cavity 210 needs to be larger than the width of the circuit board 310 extending into the second cavity 210. For instance, the width of the circuit board 310 is 4.8 mm, and the diameter of the second cavity 210 can be 5 mm. This is merely an example and is not intended to be limiting.

[0076] Furthermore, it should be noted that the adjustable resistor 320 is at least partially located within the second cavity 210. Specifically, the adjustable resistor 320 may include an operable area 321 for adjusting resistance or potential, such as an adjusting nut. The operable area 321 is at least completely housed within the second cavity 210 to facilitate adjustment of the adjustable resistor 320 when the tail plug 200 is removed. The area of ​​the adjustable resistor 320 other than the operable area 321 may be placed within the housing 100 or the tail plug 200.

[0077] In some exemplary embodiments, the housing 100 serves as the main housing component of the proximity sensor and can be implemented using threaded tubing or the like.

[0078] As shown in Figures 1 to 3, in some embodiments, the proximity sensor further includes a head plug 700, a magnetic core 500, and a coil 600. The magnetic coil is assembled onto the magnetic core 500 and housed and fixed in the head plug 700. The head plug 700 is connected to the head end 100A of the housing 100. The circuit board 310 is electrically connected to the magnetic core 500 via enameled wire or other conductors. The head plug 700 can be fixed to the housing 100 with instant adhesive, and then the entire assembly can be fixed with filler adhesive (e.g., potting compound) 800.

[0079] In addition, in some exemplary embodiments, as shown in FIG1, the tail plug 200 includes a first connecting portion 201 for connecting to the tail end 100B, the first connecting portion 201 being inserted into the tail end 100B, and the first connecting portion 201 and the tail end 100B being interference-fitted.

[0080] By using the above solution, the tail plug 200 can be easily removed from the tube shell 100 by interfering with the tube shell 100, while ensuring the fixation effect between the tail plug 200 and the tube shell 100.

[0081] Please refer to Figure 1. The first connecting part 201 can be constructed as a hollow shaft coaxial with the shell 100.

[0082] In some exemplary embodiments, as shown in Figures 1, 4 to 6, at least one of the circumferential outer surface of the first connecting portion 201 and the axial inner surface of the tail end 100B is provided with a sealing protrusion structure 2011, and the first connecting portion 201 is interference-fitted with the tail end 100B through the sealing protrusion structure 2011.

[0083] In the above scheme, as exemplified in Figure 5, the sealing protrusion structure 2011 includes at least one sealing protrusion ring 2011' circumferentially surrounding the first connecting portion 201. For example, as shown in Figure 5, in some embodiments, there may be two sealing protrusion rings 2011'. The number of sealing protrusion rings 2011' is not limited here.

[0084] In the above solution, by providing a sealing protrusion structure 2011 on the circumferential outer surface of the first connecting part 201, the purpose of interference fit between it and the tail end 100B is achieved. The structure is simple, easy to process and form, and can enhance the fixing effect between the tube shell 100 and the tail plug 200.

[0085] In addition, the first connecting part 201 and the tube shell 100 can be fixed by the filler glue 800 in addition to the interference fit between them. The sealing protrusion structure 2011 can not only improve the fit stability between the tube shell 100 and the tail plug 200, but also prevent glue overflow and leakage.

[0086] Furthermore, a smaller interference fit facilitates assembly and disassembly, while a larger interference fit results in a stronger connection. In some embodiments, taking an M8 proximity sensor as an example, the diameter of an M8 proximity sensor is 8 mm, and its single-sided interference fit can be between 0.07 and 0.15 mm, for example, a single-sided interference fit can be approximately 0.1 mm.

[0087] However, the interference fit between the first connecting part 201 and the shell 100 is not limited to this. For example, the inner diameter of the entire first connecting part 201 can be designed to be slightly larger than or equal to the diameter of the tail end 100B of the shell 100 to achieve an interference fit between the two; or, the first connecting part 201 and the shell 100 can also be fitted with a threaded interference fit.

[0088] In some exemplary embodiments, as shown in Figures 3 and 4, at least one radial groove or radial hole 2012 is provided on the circumferential outer surface of the first connecting portion 201, and the first connecting portion 201 is fixed to the tail end 100B by a filler adhesive 800, and at least a portion of the filler adhesive 800 is located in the radial groove or radial hole 2012.

[0089] By employing the above solution, providing radial grooves or radial holes 2012 on the first connecting portion 201 can enhance the fixing effect between the tube shell 100 and the tail plug 200. Specifically, when the tube shell 100 and the tail plug 200 are filled with filler (e.g., potting compound), the filler will penetrate into the radial grooves or radial holes 2012 and solidify, forming a slot-like structure, thereby strengthening the fixing effect.

[0090] The size, shape, and number of the radial grooves or radial holes 2012 can be designed according to actual needs, and this disclosure does not limit them. For example, taking an M8 size proximity sensor as an example, the diameter of the radial grooves or radial holes 2012 can be 1.5 mm, and the number can be 2. The shape of the radial grooves or radial holes 2012 can be any suitable shape such as circle, square, triangle, or polygon.

[0091] In some embodiments, as shown in FIG4, the radial groove or radial hole 2012 may be located on the sealing protrusion structure 2011, and the diameter of the radial groove or radial hole 2012 is greater than the width of the sealing protrusion structure 2011. However, it is not limited to this.

[0092] Furthermore, in some exemplary embodiments, as shown in Figures 1 to 12, the electrical component 300 further includes a light-emitting element 340 disposed on the circuit board 310; the tail plug 200 is configured as a lampshade structure, which includes a light-transmitting substrate 200', the substrate 200' including a first connecting portion 201 connected to the tail end 100B, and also including a light-emitting portion 202 for emitting light, wherein the light-emitting portion 202 is located on the side of the first connecting portion 201 axially away from the tail end 100B.

[0093] Using the above scheme, the light-emitting element 340 and the light-emitting part 202 work together as an indicator light to achieve the purpose of setting the indicator light of the proximity sensor at the tail of the proximity sensor. The working status of the proximity sensor can be characterized by changes in the color, brightness and other aspects of the indicator light.

[0094] In some embodiments, the light-emitting portion 202 circumferentially surrounds the light-emitting element 340. In other words, the light-emitting portion 202 can be in the shape of a circular ring surrounding the light-emitting element 340, thereby achieving a 360° surround view display effect.

[0095] The uniformity of the indicator light's brightness greatly affects the proximity sensor's display performance and product positioning. In related technologies, the indicator lights on proximity sensors exhibit significant differences in brightness, and the position of the light-emitting element 340 on the circuit board 310 is subject to strict requirements, resulting in poor layout flexibility for the circuit board 310.

[0096] In some exemplary embodiments of this disclosure, the substrate 200' is made of a transparent substrate material and scattering particulate material doped in the transparent substrate material, wherein the scattering particulate material includes titanium dioxide; the transparent substrate material includes at least one of polycarbonate (PC) and acrylonitrile-butadiene-styrene (ABS). Thus, by doping the substrate 200' with scattering particulate material such as titanium dioxide, the scattering effect of light within the substrate 200' can be enhanced, thereby improving the uniformity of light emission.

[0097] The proportion of the dopant material added to the transparent matrix material is not limited here. For example, in some embodiments, the mass ratio of the transparent matrix material to the dopant material is 2000:1.

[0098] Furthermore, in some exemplary embodiments, as shown in Figures 10 to 12, the interior of the substrate 200' has the second cavity 210, and the inner wall surface a of the substrate 200' can be a mirror to improve light transmittance; the outer wall surface b of the substrate 200' can be a frosted surface at least in the area corresponding to the light-emitting part 202 to increase the diffuse reflection effect of the emitted light.

[0099] It should be noted that in the above scheme, the light-emitting part 202 surrounds the light-emitting element 340 in a circumferential manner. This can be that the light-emitting part 202 is directly opposite to the light-emitting element 340 and surrounds the light-emitting element 340 in a circumferential manner, or it can be that the light-emitting part 202 is offset from the light-emitting element 340 and surrounds the light-emitting element 340 in a circumferential manner.

[0100] Furthermore, in some exemplary embodiments, as shown in FIG3, the light-emitting portion 202 circumferentially surrounds the trimming device 320, and in the axial direction of the housing 100, the light-emitting portion 202 is directly opposite the trimming device 320, and the width of the light-emitting portion 202 is greater than or equal to the width of the trimming device 320.

[0101] In the above scheme, the first connecting part 201 is connected to the light-emitting part 202. Since the first connecting part 201 is located on the side of the light-emitting part 202 near the tube shell 100 and connected to the tail end 100B of the tube shell 100, the light-emitting part 202 is the main structure constituting the space for accommodating the circuit board 310 and the adjusting device 320. Therefore, the adjusting device 320 can be positioned directly opposite the light-emitting part 202 along the axial direction of the tube shell 100, and the width of the light-emitting part 202 is greater than or equal to the width of the adjusting device 320. In this way, it can be ensured that the tail plug 200 has enough space to accommodate the circuit board 310 and the adjusting device 320. Furthermore, after the tail plug 200 is removed, the adjusting device 320 can be fully exposed for adjustment.

[0102] For example, along the axial direction of the housing 100, the width of the trimming device 320 can be 2 mm, and the width of the light-emitting section 202 can be 2.5 mm, where 0.5 mm is the assembly tolerance value. However, the above is only an example, and the dimensions of the light-emitting section 202 and the trimming device 320 are not limited thereto.

[0103] Furthermore, in some embodiments, the difference between the maximum diameter of the light-emitting portion 202 and the maximum diameter of the housing 100 is less than or equal to a first threshold. This first threshold can be as close to 0 as possible so that the tail plug 200 is approximately flush with the outer surface of the housing 100. Here, "approximately" means within one or more standard deviations, or within 3% or 5% of that value. For example, in some embodiments, the maximum outer diameter of the housing 100 and the light-emitting portion 202 can be 6.7 mm.

[0104] Furthermore, in some exemplary embodiments, as shown in Figures 10 to 15, a reflective structure 204 is provided on at least one of the circumferential inner surface and the circumferential outer surface of the tail plug 200. The reflective structure 204 is positioned directly opposite the light-emitting element 340 in the axial direction of the tube housing 100, and the reflective structure 204 is configured to reflect at least a portion of the light emitted by the light-emitting element 340 to the light-emitting portion 202.

[0105] By adopting the above solution, by setting the reflective structure 204 on the tail plug 200 at the position corresponding to the light-emitting element 340, it can be ensured that more light enters the light-emitting part 202 after reflection. Furthermore, due to the setting of the reflective structure 204, the layout position of the light-emitting element 340 can be more flexible. For example, the light-emitting element 340 can be arranged at any position in the tail plug 200, as long as the light is reflected to the light-emitting part 202 through the reflective structure 204, which provides convenience for the layout of the circuit board 310.

[0106] In some exemplary embodiments, as shown in Figures 10 to 14, the reflective structure 204 includes a reflective section 2041 that is axially inclined relative to the housing 100, the inclination angle of the reflective section 2041 relative to the housing 100 being 30 to 60°. For example, the inclination angle of the reflective section 2041 relative to the housing 100 is 45°.

[0107] Please refer to Figures 10 and 11. In some embodiments, the reflective structure 204 is disposed on the first connecting portion 201. Since the light-emitting portion 202 is located on the side of the first connecting portion 201 away from the housing 100, the inclination direction of the reflective surface 2041 is: from the side close to the light-emitting portion 202 to the side away from the light-emitting portion 202, gradually tilting towards the center of the first connecting portion 201. The light-emitting element 340 can be disposed directly opposite the reflective surface 2041, so that the light from the light-emitting element 340 can be reflected to the light-emitting portion 202 via the reflective surface 2041.

[0108] It is understood that the above is merely an example, and in other embodiments, the tilt angle and tilt direction of the reflective surface 2041 are not limited thereto. Furthermore, the reflective surface 2041 may be arranged circumferentially around the first connecting portion 201, and there may be only one reflective surface 2041, or there may be two or more.

[0109] Furthermore, it should be noted that the reflective structure 204 may be arranged on the circumferential inner surface of the tail plug 200, or on the circumferential outer surface of the tail plug 200, or on both the circumferential inner and outer surfaces of the tail plug 200.

[0110] As shown in Figure 15, when the reflective structure 204 is provided on both the inner and outer circumferential surfaces of the tail plug 200, the reflective structure 204 on the inner circumferential surface 2001 of the tail plug 200 can be located at different positions from the reflective structure 204 on the outer circumferential surface 2002 of the tail plug 200.

[0111] Furthermore, in some exemplary embodiments, as shown in Figures 10 to 14, the light-emitting portion 202 includes an adjacent light-emitting surface 202a and a light-concentrating surface 202b. The light-emitting surface 202a is an annular arc surface, and the light-concentrating surface 202b is an annular oblique surface. The light-concentrating surface 202b is configured to converge at least a portion of the light emitted by the light-emitting element 340.

[0112] In the above scheme, the annular arc surface refers to a three-dimensional curved surface, which is a flat surface formed by bending or rotating an annular boundary (i.e., a ring) along a certain direction. The annular oblique surface refers to a cross-section formed by a plane passing through an annular object at an oblique angle. In other words, the light-emitting surface 202a can be regarded as an annular surface parallel to the axial direction of the tube shell 100, and the light-concentrating surface 202b is inclined relative to the light-emitting surface 202a. In this way, at least part of the light from the light-emitting element 340 can be directly emitted through the light-emitting surface 202a, and at least part of the light can be focused by the light-concentrating surface 202b before being emitted, which can enhance the brightness of the light-emitting part 202.

[0113] In some embodiments, the angle β of the light-concentrating surface 202b relative to the light-emitting surface 202a can be 30 to 60°, for example, β is 45°. However, it is not limited to this.

[0114] Along the axial direction of the tube shell 100, the width of the light-emitting surface 202a can be adjusted according to the layout of the circuit board 310 inside the tail plug 200. For example, the width of the light-emitting surface 202a can be greater than or equal to the width of the adjustable resistor 320.

[0115] Furthermore, in some exemplary embodiments, as shown in Figures 10 to 15, a prism structure 205 is provided on at least one of the circumferential inner surface and the circumferential outer surface of the tail plug 200. The prism structure 205 is configured to diffuse the light emitted from the light-emitting element 340. By providing the prism structure 205, the light emitted from the light-emitting element 340 can undergo multiple reflections and refractions when passing through the surface of the prism structure 205, thereby making the light distribution in the light-emitting portion 202 more uniform.

[0116] For example, as shown in Figures 10 to 17, the prism structure 205 includes an array of distributed prism structures 2053 or pyramid structures 2052.

[0117] For example, in some embodiments, the plurality of prism structures 2053 may be arranged in one or more rings along the circumferential inner surface of the tail plug 200. The prism structure 2053 may be a triangular prism structure 2053 with a triangular cross-section (e.g., an isosceles triangle), which allows light to diffuse uniformly over a large angular range. It is understood that the prism structure 2053 is not limited to a triangular prism structure 2053, and its cross-section may include, but is not limited to, triangles, ellipses, semicircles, polygons, etc.

[0118] For example, in some embodiments, as shown in Figure 16, the pyramid structure 2052 can be a triangular pyramid structure, such as a regular triangular pyramid structure, and the lateral faces 2050 of the regular triangular pyramid structure are isosceles right triangles. Referring to Figure 17, in other embodiments, the pyramid structure 2052 can also be a square pyramid structure, such as a regular square pyramid structure, and the lateral faces 2050 of the regular square pyramid structure are equilateral triangles. It is understood that the specific implementation of the pyramid structure 2052 is not limited to these.

[0119] Furthermore, in some exemplary embodiments, the prism structure 205 includes a plurality of side surfaces 2050, and at least some of the side surfaces 2050 are configured to reflect light emitted from the light-emitting element 340 to the light-emitting portion 202. Thus, the prism structure 205 can also function as a light reflector.

[0120] In some embodiments, when the prism structure 205 can also serve as a light reflector, the reflective structure 204 can be omitted from the tail plug 200. For example, as shown in FIG15, the prism structure 205 is disposed on the circumferential outer surface of the tail plug 200, and the prism structure 205 is configured such that at least a portion of the side surface 2050 can reflect the light emitted from the light-emitting element 340 to the light-emitting portion 202.

[0121] Furthermore, it should be noted that the arrangement of the prism structure 205 on the tail plug 200 can be combined with the actual product and optical path. For example, at least part of the prism structure 205 can be arranged in the area corresponding to the light-emitting surface 202a, but it is not limited thereto.

[0122] It should be noted that, as shown in Figure 21, the tail plug 200 can be an integrally molded structural component. For example, the tail plug 200 can be formed by injection molding. Optical structures such as the prism structure 205 and / or the reflection structure 204 can be set in the tail plug 200 without increasing the difficulty of mold opening.

[0123] Furthermore, in some exemplary embodiments, as shown in FIG6, the first outlet hole 220 has an outer port 220a away from the second cavity 210 and an inner port 220b close to the second cavity 210, and the first outlet hole 220 is configured to gradually narrow from the outer port 220a to the inner port 220b.

[0124] In the above solution, the first cable outlet 220 on the tail plug 200 is constructed such that the outer port 220a is wide and the inner port 220b is narrow. For example, the first cable outlet 220 can be roughly flared. This facilitates the cable 330 to pass through the outer port 220a and allows the cable 330 to be secured through the inner port 220b to prevent the cable 330 from becoming loose. When filling the tail plug 200 with potting compound, it can prevent glue leakage, thereby ensuring the stability of the electrical connection and improving the reliability of the product.

[0125] In some embodiments, the inner diameter of the inner port 220b may be approximately the same as the diameter of the cable 330, and the inner diameter of the outer port 220a may be larger than the diameter of the cable 330, for example, the difference between the inner diameter of the outer port 220a and the diameter of the cable 330 may be approximately 0.2 mm. For example, the diameter of the cable 330 may be 2.8 mm, the inner diameter of the inner port 220b may be 2.8 mm, and the inner diameter of the outer port 220a may be 3.0 mm. However, this is not a limitation.

[0126] In some exemplary embodiments, as shown in Figures 22 to 25, the circumferential inner wall of the inner port 220b can be constructed as an edge-shaped structure 220c or a surface structure 220d. In other words, the inner port 220b can have line-to-surface or surface-to-surface contact with the cable 330.

[0127] Since the cable 330 needs to pass through the first outlet hole 220, if the contact area between the inner port 220b and the cable 330 is too large, the friction will be too great, which will cause the cable 330 to be unable to pass through the first outlet hole 220 smoothly.

[0128] Therefore, when the circumferential inner wall of the inner port 220b is a ridge-shaped structure 220c, the contact area between the first outlet hole 220 and the cable 330 is small. This ensures that the cable 330 is securely fastened while also facilitating the smooth passage of the cable 330 through the first outlet hole 220.

[0129] When the circumferential inner wall of the inner port 220b is a planar structure 220d, the width of the circumferential inner wall of the inner port 220b along the axial direction of the tube shell 100 should not be too large, so as to avoid generating large frictional force and causing difficulty in threading. For example, the width of the planar structure 220d along the axial direction of the tube shell 100 can be less than or equal to 0.5mm.

[0130] Furthermore, as shown in Figure 6, in some embodiments, when the circumferential inner wall of the inner port 220b is a ridge-shaped structure 220c, the tail plug 200 has an end cap 206 at the end where the first cable outlet 220 is located, and the first cable outlet 220 is disposed on the end cap 206. As shown in Figures 22 and 23, the inner wall 2061 of the end cap 206 facing the second cavity 210 can be a vertical wall perpendicular to the cable 330 or an inclined wall inclined relative to the cable 330.

[0131] Similarly, as shown in Figure 6, in some embodiments, when the circumferential inner wall of the inner port 220b is a planar structure 220d, the tail plug 200 has an end cap 206 at the end where the first cable outlet 220 is located, and the first cable outlet 220 is disposed on the end cap 206. As shown in Figures 24 and 25, the inner wall 2061 of the end cap 206 facing the second cavity 210 can be a vertical wall perpendicular to the cable 330 or an inclined wall inclined relative to the cable 330.

[0132] In some exemplary embodiments, as shown in Figures 1, 18 to 20, the proximity sensor further includes a cable protective sleeve 400, which includes a sleeve portion 410 and a flexible protective portion 420. The sleeve portion 410 is sleeved on the end of the tail plug 200 that has the first cable outlet hole 220, and the flexible protective portion 420 has a second cable outlet hole 430. The cable 330 passing through the first cable outlet hole is inserted into the second cable outlet hole 430.

[0133] By adopting the above solution and setting the cable protective sleeve 400, the bending and twisting resistance of the cable 330 can be improved, the tensile strength can be increased, and the aesthetic effect can be achieved.

[0134] Furthermore, in related technologies, in order to improve the tensile strength of the cable 330, the circuit board 310 is built into the housing 100 to ensure that the filler adhesive can completely wrap the protective layer of the cable 330, which prevents the resistance adjustment device 320 from being placed outside the housing 100. However, in the above solution, by setting the cable protective sleeve 400, it can be ensured that the tensile strength requirements of the cable 330 can be met even when the resistance adjustment device 320 is placed outside the housing 100.

[0135] In some exemplary embodiments, the flexible protective part 420 has a plurality of openings 440 on its peripheral surface, and the plurality of openings 440 are arranged sequentially along the axial direction of the cable 330 to form a plurality of opening units S. Each opening unit S includes at least one opening 440 arranged along the circumferential direction of the cable 330, and the openings 440 in two adjacent opening units S are arranged alternately.

[0136] By adopting the above solution, by providing multiple openings 440 on the circumferential surface of the flexible protective part 420, it is not only beneficial for the bending of the cable 330, but also serves to support the cable 330, thereby improving the tensile and bending resistance of the cable 330.

[0137] In some exemplary embodiments, the opening 440 has a circumferential dimension of 4±1mm along the cable 330, an axial dimension of 0.6±0.2mm along the cable 330, and the spacing between two adjacent opening units S in the axial direction of the cable 330 is 1±0.5mm.

[0138] It should be understood that the above is only an example, and the flexible protective part 420 is not limited to this in terms of the way it can be flexibly bent, nor are the number, shape and size of the openings 440 limited to this.

[0139] In some embodiments, the cable protective sleeve 400 may be made of any suitable material such as rubber.

[0140] Furthermore, in some exemplary embodiments, as shown in Figures 1 to 6 and Figures 18 to 20, the tail plug 200 further includes a second connecting portion 203 for connecting with the sleeve portion 410. The outer circumferential surface of the second connecting portion 203 is provided with a concave-convex structure 2031, and the inner circumferential surface of the sleeve portion 410 is provided with a concave-convex fitting structure 411. The sleeve portion 410 is sleeved on the second connecting portion 203, and the concave-convex structure 2031 cooperates with the concave-convex fitting structure 411 to engage and fix the sleeve portion 410 and the second connecting portion 203.

[0141] For example, the concave-convex structure 2031 may include a groove provided on the circumferential outer surface of the second connecting portion 203, and the concave-convex fitting structure 411 may include a protrusion provided on the circumferential inner surface of the sleeve portion 410. The specific construction of the concave-convex structure 2031 and the concave-convex fitting structure 411 is not limited.

[0142] The above solution, through the cooperation of the concave-convex structure 2031 and the concave-convex adapter structure 411, ensures a secure connection between the tail plug 200 and the cable protective sleeve 400. Taking an M8 size proximity sensor as an example, the concave or convex height of the concave-convex structure 2031 relative to the axial outer surface of the second connecting part 203 can be 0.2 to 0.5 mm, for example, 0.3 mm. However, it is not limited to this.

[0143] It should be noted that the above is only one example. In other embodiments, as shown in Figure 21, the tail plug 200 can also be integrally formed with the cable protective sleeve 400 by, for example, hot pressing or an integral mold.

[0144] Furthermore, in some exemplary embodiments, as shown in Figures 1 to 4, when the tail plug 200 is constructed as a lampshade structure, it includes a light-emitting portion 202, the second connecting portion 203 is located on the side of the light-emitting portion 202 away from the tube shell 100, and the difference between the maximum diameter of the sleeve portion 410 and the maximum diameter of the light-emitting portion 202 is less than or equal to a second threshold.

[0145] In other words, the difference between the outer diameter of the light-emitting portion 202 and the outer diameter of the sleeve portion 410 is within the second threshold. The second threshold can be as close to 0 as possible so that the tail plug 200 is approximately flush with the outer surface of the tube shell 100. Here, "approximately" means within one or more standard deviations, or within 3% or 5% of the value.

[0146] Furthermore, in some exemplary embodiments, as shown in FIG1, the cable 330 located in the second cavity 210 includes a wire exposure area 331 and a wire wrapping area 332. The wire exposure area 331 is electrically connected to the circuit board 310, and the length of the wire wrapping area 332 along the extension direction of the cable 330 is greater than or equal to 3mm.

[0147] In the above scheme, the exposed conductor area 331 refers to the area where the conductor of the cable 330 is not covered with protective sheath; the conductor-wrapped area 332 refers to the area where the conductor of the cable 330 is wrapped with insulating protective sheath. To ensure the fixing effect of the cable 330, at least a portion of the cable 330 in the second cavity 210 is the conductor-wrapped area 332, that is, the conductor is wrapped with protective sheath. In this way, when the tail plug 200 is inverted and potted, the filler 800 can be replaced and bonded to the cable 330, improving the tensile strength of the cable 330.

[0148] The conductor wrapping area 332 has a length greater than or equal to 3 mm along the extension direction of the cable 330 to further ensure the adhesion between the cable 330 and the potting compound. It should be noted that when the length of the conductor wrapping area 332 is greater than or equal to 3 mm, the length of the second cavity 210 can also be greater than or equal to 3 mm. However, this is not a limitation.

[0149] The following points need to be explained:

[0150] (1) The accompanying drawings of the embodiments of this disclosure only involve the structures involved in the embodiments of this disclosure. Other structures can be referred to the general design.

[0151] (2) For clarity, the thickness of layers or regions is enlarged or reduced in the drawings used to describe embodiments of the present disclosure, i.e., these drawings are not drawn to actual scale. It will be understood that when an element such as a layer, film, region or substrate is referred to as being “above” or “below” another element, the element may be “directly” located “above” or “below” the other element or there may be intermediate elements.

[0152] (3) Where there is no conflict, the embodiments of this disclosure and the features in the embodiments can be combined with each other to obtain new embodiments.

[0153] The above are merely specific embodiments of this disclosure, but the scope of protection of this disclosure is not limited thereto. The scope of protection of this disclosure shall be determined by the scope of the claims.

Claims

A proximity sensor characterized by, include: A shell having an axially penetrating first cavity, the shell including a head end and a tail end opposite each other along the axial direction; The tail plug has a second cavity inside. One axial end of the tail plug is connected to the tail end of the tube shell, and the other axial end of the tail plug is provided with a first outlet hole that communicates with the second cavity. and An electrical component includes a circuit board and a resistor adjustment device disposed on the circuit board. A portion of the circuit board is housed in a first cavity, and another portion extends from the tail end into a second cavity. The resistor adjustment device is at least partially located in the second cavity. A cable is connected to the circuit board and passes through the first outlet hole and exits the second cavity. The proximity sensor according to claim 1, wherein The tail plug includes a first connecting portion for connecting to the tail end, the first connecting portion being inserted into the tail end, and the first connecting portion and the tail end being interference-fitted. The proximity sensor according to claim 2, wherein At least one of the circumferential outer surface of the first connecting part and the axial inner surface of the tail end is provided with a sealing protrusion structure, and the first connecting part is interference-fitted with the tail end through the sealing protrusion structure. The proximity sensor according to claim 3, characterized in that The sealing protrusion structure includes at least one sealing protrusion ring arranged circumferentially around the first connecting portion. The proximity sensor according to claim 2, wherein The first connecting part has at least one radial groove or radial hole on its circumferential outer surface. The first connecting part is fixed to the tail end by a filler adhesive, and at least part of the filler adhesive is located in the radial groove or radial hole. The proximity sensor according to claim 1, wherein The electrical components also include a light-emitting element disposed on the circuit board; the tail plug is configured as a lampshade structure, which includes a light-transmitting substrate, the substrate including a first connecting portion connected to the tail end and a light-emitting portion for emitting light, wherein the light-emitting portion is located on the side of the first connecting portion axially away from the tail end, and the light-emitting portion circumferentially surrounds the light-emitting element. The proximity sensor according to claim 6, characterized in that The substrate material includes a transparent substrate material and scattering particle material doped in the transparent substrate material, wherein the scattering particle material includes titanium dioxide. The proximity sensor according to claim 6, characterized in that The light-emitting part circumferentially surrounds the trimming device, and in the axial direction of the tube shell, the light-emitting part is directly opposite the trimming device. The width of the light-emitting part is greater than or equal to the width of the trimming device. The difference between the maximum diameter of the light-emitting part and the tube shell is less than or equal to a first threshold. The proximity sensor according to claim 6, characterized in that The tail plug has a reflective structure on at least one of its circumferential inner surface and circumferential outer surface. The reflective structure is positioned directly opposite the light-emitting element in the axial direction of the tube shell, and the reflective structure is configured to reflect at least a portion of the light emitted by the light-emitting element to the light-emitting portion. The proximity sensor according to claim 9, characterized in that The reflective structure includes a reflective sectional surface that is axially inclined relative to the shell, and the axial inclination angle of the reflective sectional surface relative to the shell is 30 to 60°. The proximity sensor according to claim 6, characterized in that The light-emitting part includes an adjacent light-emitting surface and a light-concentrating surface. The light-emitting surface is an annular arc surface, and the light-concentrating surface is an annular oblique surface. The light-concentrating surface is configured to converge at least a portion of the light emitted by the light-emitting element. The proximity sensor according to claim 6, characterized in that A prism structure is provided on at least one of the circumferential inner surface and the circumferential outer surface of the tail plug, the prism structure being configured to diffuse the light emitted from the light-emitting element. The proximity sensor according to claim 12, wherein The prism structure includes an array of prisms or pyramids. The proximity sensor according to claim 12, wherein The prism structure includes multiple sides, and at least some of the sides are configured to reflect light emitted from the light-emitting element to the light-emitting portion. The proximity sensor according to claim 1, wherein The first outlet has an outer port away from the second cavity and an inner port close to the second cavity. The first outlet is configured to gradually narrow from the outer port to the inner port. The proximity sensor of claim 15, wherein The circumferential inner wall of the inner port is constructed as an edge-like structure or a planar structure. The proximity sensor according to claim 1, wherein The proximity sensor also includes a cable protective sleeve, which includes a sleeve portion and a flexible protective portion. The sleeve portion is fitted onto the end of the tail plug that has the first cable outlet hole, and the flexible protective portion has a second cable outlet hole. The cable that passes through the first cable outlet hole is inserted into the second cable outlet hole. The proximity sensor of claim 17, wherein The flexible protective part has multiple openings on its circumferential surface, and the multiple openings are arranged sequentially along the axial direction of the cable to form multiple opening units. Each opening unit includes at least one opening arranged along the circumferential direction of the cable, and the openings in two adjacent opening units are staggered. The proximity sensor of claim 18, wherein The opening has a circumferential dimension of 4±1mm and an axial dimension of 0.6±0.2mm, and the spacing between two adjacent opening units in the axial direction of the cable is 1±0.5mm. The proximity sensor of claim 17, wherein The tail plug includes a second connecting portion for connecting with the sleeve portion. The outer circumferential surface of the second connecting portion is provided with a concave-convex structure, and the inner circumferential surface of the sleeve portion is provided with a concave-convex fitting structure. The sleeve portion is sleeved on the second connecting portion, and the concave-convex structure cooperates with the concave-convex fitting structure to engage and fix the sleeve portion and the second connecting portion. The proximity sensor of claim 20, wherein The height of the recess or protrusion of the concave-convex structure relative to the axial outer surface of the second connecting part is 0.2 to 0.5 mm. The proximity sensor of claim 20, wherein The tail plug is configured as a lampshade structure, which includes a light-emitting part, wherein the second connecting part is located on the side of the light-emitting part away from the tube shell, and the difference between the maximum diameter of the sleeve part and the maximum diameter of the light-emitting part is less than or equal to a second threshold. The proximity sensor according to claim 1, wherein The cable located in the second cavity includes an exposed conductor area and a conductor wrapping area. The exposed conductor area is electrically connected to the circuit board, and the conductor wrapping area has a length greater than or equal to 3 mm along the extension direction of the cable.

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