A lens holder and a background suppression photoelectric sensor having the same

Abstract

This invention relates to the field of photoelectric sensor technology, specifically to a lens holder and a background suppression photoelectric sensor having the same. The lens holder supports a lens and an adjustment knob. The lens holder includes a support body with a hollow frame adapted to support the lens; at least two elastic arms extending outward from an outer wall of the support body; each elastic arm has a positioning portion extending inward, with a positioning surface at its top; the positioning surfaces of each elastic arm cooperate to support the adjustment knob. This lens holder can support the lens and adjustment knob within the photoelectric sensor; the positioning surfaces of the elastic arms of the lens holder, used to support the adjustment knob, are equivalent to having a grip section integrated with the support body in front of the lens holder body, which can improve the stability of the adjustment knob and thus improve adjustment accuracy.

Description

Technical Field

[0001] This invention relates to the field of photoelectric sensor technology, and more specifically to a lens holder and a photoelectric sensor having the same. Background Technology

[0002] Background suppression photoelectric sensors are less affected by changes in the color of the object being detected, and can detect objects of almost equal color at nearly the same distance. Background suppression involves shielding the background, so detection is not affected by it. Background suppression photoelectric sensors are set to a specific detection distance; objects beyond the set distance will not be detected, thus effectively avoiding background interference. Background suppression photoelectric sensors detect objects based on the triangulation principle. For example, on a production line with many objects of different colors, where the background is the same color as the object being detected, ordinary diffuse reflection photoelectric sensors can easily cause false triggering or fail to detect lighter-colored objects. In such cases, a background suppression photoelectric sensor is needed to shield the background and detect only the object.

[0003] Background suppression photoelectric sensors feature an adjustable receiving lens, with the receiver divided into a far-end region and a near-end region. The intensity of light reflected back from objects at different distances will differ between the far-end and near-end regions. To detect the target, the detection distance can only be changed by adjusting the receiving lens. In existing background suppression photoelectric sensors, one end of the adjustment knob is fixed to the housing, while the other end is screwed onto the adjustable receiving lens. This can lead to instability in the adjustment knob, potentially amplifying errors during the adjustment process. Summary of the Invention

[0004] Therefore, the technical problem to be solved by the present invention is to overcome the above-mentioned defects in the prior art, thereby providing a lens holder and a photoelectric sensor having the same.

[0005] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:

[0006] The present invention provides a lens holder for supporting a lens and an adjustment knob. The lens holder includes a holder body having a hollow frame adapted to support the lens; at least two elastic arms extending outward from an outer side wall of the holder body, each elastic arm having a positioning portion extending inward, the top of the positioning portion having a positioning surface; the positioning surfaces of each elastic arm cooperate with each other to support the adjustment knob.

[0007] The lens bracket provided by the present invention has an arc-shaped positioning surface, a first anti-retraction surface on the side of the positioning part facing the bracket body, and an arc-shaped guide slope on the side of the positioning part facing away from the bracket body; the arc-shaped positioning surface is connected to the first anti-retraction surface and the arc-shaped guide slope respectively.

[0008] The lens holder provided by the present invention further includes an elastic lug extending outward from the elastic arm, the elastic lug being disposed opposite to the positioning part.

[0009] The present invention also provides a background suppression photoelectric sensor, including a housing and a light emitting module and a light receiving module disposed within the housing; the light receiving module includes a receiver, an adjustment knob, a receiving lens, and the aforementioned lens bracket; the adjustment knob passes through the housing and the lens bracket and is movably connected to the receiving lens; the light emitting module includes a light emitting element and an emitting lens.

[0010] The background suppression photoelectric sensor provided by the present invention has an adjustment knob having a rod-shaped body located between the positioning surfaces of the elastic arm, and the end of the rod-shaped body having a thread; the receiving lens has a threaded structure that mates with the thread at the end of the rod-shaped body.

[0011] The background suppression photoelectric sensor provided by the present invention has a shoulder outer ring in the middle of the rod-shaped body. The first end of the shoulder outer ring has a second anti-retraction surface that cooperates with the first anti-retraction surface, and the second end of the shoulder outer ring has a guide slope that cooperates with the arc-shaped guide slope when inserted.

[0012] The background suppression photoelectric sensor provided by the present invention includes a receiving lens comprising a lens sheet and a lens mount, the lens mount being slidably disposed on the support body; the lens sheet being snapped onto the lens mount, and a threaded structure being disposed on the lens mount.

[0013] The background suppression photoelectric sensor provided by the present invention has guide rails inside the two side walls of the hollow frame; the lens mount has a slide block that slides with the guide rails.

[0014] The background suppression photoelectric sensor provided by the present invention includes a driving sleeve on the lens mount, and a threaded structure inside the driving sleeve; a support block is also provided on the hollow frame, and the support block is disposed inside the base of at least two elastic arms; the upper part of the support block supports the driving sleeve.

[0015] The background suppression photoelectric sensor provided by the present invention has a lens mount having a lens bearing surface, at least one limiting protrusion and several buckles, wherein the limiting protrusion and the buckles are all disposed around the lens bearing surface and extend upward; the edge of the lens sheet has a limiting groove that cooperates with the limiting protrusion and a snap-fit ​​portion that engages with the buckles.

[0016] The background suppression photoelectric sensor provided by the present invention has a emitting lens mounting frame inside the housing, and the emitting lens is embedded in the mounting frame; at least one of the emitting lens and the inner wall of the mounting frame is provided with a plurality of limiting ribs.

[0017] The background suppression photoelectric sensor provided by the present invention has a lens bracket disposed on one side of the transmitting lens mounting frame, and the lens element of the receiving lens is obliquely disposed toward one side of the transmitting lens.

[0018] The background suppression photoelectric sensor provided by the present invention has a plurality of abutment ribs on the inner wall of the housing, and the abutment ribs support the lens bracket.

[0019] The background suppression photoelectric sensor provided by the present invention further includes: a first circuit board, wherein a receiver and a light-emitting element are disposed on the working surface of the first circuit board, the receiver and the light-emitting element being respectively disposed corresponding to the receiving lens and the emitting lens; and a second circuit board electrically connected to the first circuit board, the second circuit board being disposed on the back side of the first circuit board and disposed parallel to the first circuit board.

[0020] The background suppression photoelectric sensor provided by the present invention has, within the housing, multiple guide ribs that abut against the outer wall of the lens bracket; and multiple positioning posts that pass through the first or second circuit board and are fixedly connected to the circuit board through which they pass.

[0021] The background suppression photoelectric sensor provided by the present invention further includes a shielding circuit board between the first circuit board and the second circuit board, wherein the shielding circuit board is preferably an FPC.

[0022] The background suppression photoelectric sensor provided by the present invention further includes a shielding sheet, which has a base plate and two side plates; the two side plates extend upward on the base plate and are located on both sides of the first circuit board and the second circuit board; the shielding sheet is preferably a copper sheet.

[0023] The background suppression photoelectric sensor provided by the present invention has a base plate covering at least a portion of the working surface of the first circuit board, and the base plate has a through slot at the position corresponding to the receiver.

[0024] The technical solution of this invention has the following advantages:

[0025] 1. The lens holder provided by the present invention can support the lens and the adjustment knob inside the photoelectric sensor; the positioning surface of the elastic arm of the lens holder can be used to support the adjustment knob, which is equivalent to having a grip section integrated with the holder body in front of the lens holder body, which can improve the stability of the adjustment knob and thus improve the adjustment accuracy.

[0026] 2. The background suppression photoelectric sensor provided by this invention has an adjustment knob that passes through the housing and lens bracket and is movably connected to the receiving lens to adjust the lateral position of the receiving lens, thereby adjusting the sensor's detection distance. In this sensor, the positioning surface of the elastic arm of the lens bracket can support the adjustment knob between the housing and the receiving lens, which is equivalent to adding a stabilizer between the housing and the receiving lens, improving the stability of the adjustment knob and thus improving the adjustment accuracy.

[0027] 3. The background suppression photoelectric sensor provided by the present invention has a rod-shaped body of the adjustment knob with a shoulder outer ring. When the shoulder outer ring passes through the positioning part, due to the large width of the shoulder outer ring, it exerts a squeezing force on the positioning part, causing the elastic arm to expand outward. After the shoulder outer ring passes through, the elastic arm retracts inward under the action of elastic restoring force, thereby positioning the adjustment knob, which is simple to operate. The positioning part of the elastic arm has a first anti-retraction surface, and the shoulder outer ring of the adjustment knob has a second anti-retraction surface that cooperates with the first anti-retraction surface. After the shoulder outer ring passes through the positioning part, the cooperation of the first anti-retraction surface and the second anti-retraction surface can prevent the adjustment knob from falling off. Due to the blocking effect of the first anti-retraction surface, the adjustment knob will not be pulled out from the positioning part.

[0028] 4. The background suppression photoelectric sensor provided by the present invention has two circuit boards arranged in parallel inside the housing, which can make full use of the internal space of the sensor housing and carry more components without increasing the size of the sensor. Attached Figure Description

[0029] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0030] Figure 1 This is a schematic diagram of the background suppression photoelectric sensor structure provided in an embodiment of the present invention;

[0031] Figure 2 The internal structure of the background suppression photoelectric sensor provided in the embodiments of the present invention. Figure 1 ;

[0032] Figure 3 The internal structure of the background suppression photoelectric sensor provided in the embodiments of the present invention. Figure 2 ;

[0033] Figure 4 The internal structure of the background suppression photoelectric sensor provided in the embodiments of the present invention. Figure 3 ;

[0034] Figure 5 This is a schematic diagram of the receiving lens assembly structure provided in an embodiment of the present invention;

[0035] Figure 6 This is a schematic diagram of the lens structure provided in an embodiment of the present invention;

[0036] Figure 7 This is a schematic diagram of the lens mount structure provided in an embodiment of the present invention;

[0037] Figure 8 This is a schematic diagram of the lens support structure provided in an embodiment of the present invention. Figure 1 ;

[0038] Figure 9 This is a schematic diagram of the lens support structure provided in an embodiment of the present invention. Figure 2 ;

[0039] Figure 10 This is a schematic diagram of the adjustment knob structure provided in an embodiment of the present invention;

[0040] Figure 11 This is a schematic diagram of the receiving lens assembly and circuit board provided in an embodiment of the present invention;

[0041] Figure 12 This is a schematic diagram of the mating structure of two circuit boards provided in an embodiment of the present invention;

[0042] Figure 13 The internal structure of the background suppression photoelectric sensor provided in the embodiments of the present invention. Figure 4 .

[0043] Explanation of reference numerals in the attached figures:

[0044] 1-Housing, 101-Abutting rib, 102-Limiting rib, 103-Guide rib, 104-Positioning post, 11-Lens bracket, 111-Bracket body, 112-Support block, 113-Elastic arm, 1131-Positioning part, 1132-Elastic lug, 114-Supporting post, 115-Guide rail; 12-Lens holder, 121-Slide, 122-Snap, 123-Limiting protrusion, 124-Drive sleeve, 13-Lens plate, 131-Light transmission 132-Emitting part, 133-Limiting groove, 14-Adjusting knob, 141-Thread, 142-Outer ring with shoulder, 15-First circuit board, 151-Light-emitting element, 152-Receiver, 153-First positioning hole, 16-Second circuit board, 161-Second positioning hole, 17-Electrical connection board, 18-Shielding sheet, 19-Emitting lens, 2-Cover body, 3-Cable assembly; A-First anti-reverse surface, B-Positioning surface, C-Arc-shaped guide slope. Detailed Implementation

[0045] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0046] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for 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. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0047] Furthermore, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0048] Example 1

[0049] This embodiment provides a background suppression photoelectric sensor, such as... Figure 1-4 As shown, the background suppression photoelectric sensor provided in this embodiment includes a housing 1, a light emitting module and a light receiving module, a cover 2, and a cable assembly 3 disposed within the housing 1. The light receiving module includes a receiver 152, an adjustment knob 14, a receiving lens, and a lens holder 11. As an optional embodiment, the receiving lens includes a lens base 12 and a lens sheet 13. The adjustment knob 14 passes through the housing 1 and the lens holder 11 and is movably connected to the receiving lens to adjust the lateral distance of the receiving lens. The light emitting module includes a light emitting element 151 and a light emitting lens 19. The light emitted by the light emitting element 151 is focused by the light emitting lens 19 and emitted. After reaching the detected object, it is reflected to form reflected light, which is received by the receiving lens and the receiver 152 to obtain a detection signal.

[0050] In this embodiment, the lens holder 11 is used to support the receiving lens and the adjustment knob 14. The lens holder 11 includes a holder body 111 with a hollow frame, which is adapted to support the receiving lens; and two elastic arms 113. The elastic arms 113 extend outward from an outer side wall of the holder body 111, and each elastic arm 113 has a positioning portion 1131 extending inward. The top of the positioning portion 1131 has a positioning surface B. The positioning surfaces B of each elastic arm 113 cooperate with each other to support the adjustment knob 14. The lens holder 11 provided in this embodiment can support the receiving lens and the adjustment knob 14 inside the photoelectric sensor. The positioning surfaces B of the elastic arms of the lens holder 11 can be used to support the adjustment knob 14, which is equivalent to having a grip section integrated with the holder body in front of the lens holder body, which can improve the stability of the adjustment knob and thus improve the adjustment accuracy. Therefore, in this background suppression photoelectric sensor using the lens bracket, the adjustment knob passes through the housing and lens bracket and is movably connected to the receiving lens to adjust the lateral position of the receiving lens, thereby adjusting the sensor's detection distance. In the sensor provided in this embodiment, the positioning surface of the elastic arm of the lens bracket can support the adjustment knob between the housing and the receiving lens, which is equivalent to adding a stabilizer between the housing and the receiving lens, thus improving the stability of the adjustment knob.

[0051] As an alternative implementation, in the lens bracket described above, the elastic arm can also be set to three or more, in which case each positioning surface of the elastic arm positioning part is arranged around the adjustment knob.

[0052] In this embodiment, the positioning surface B of the lens bracket is an arc-shaped positioning surface. The positioning part 1131 has a first anti-retraction surface A on the side facing the bracket body 111, and an arc-shaped guide slope C on the side facing away from the bracket body 111. The arc-shaped positioning surface B is connected to the first anti-retraction surface A and the arc-shaped guide slope C, respectively. Figure 10 As shown, the adjustment knob 14 has a rod-shaped body, which is located between the positioning surfaces of the elastic arm. The end of the rod-shaped body 14 has a thread 141. The receiving lens has a threaded structure that mates with the thread 141 at the end of the rod-shaped body. The rod-shaped body has a shoulder outer ring 142 in the middle. The first end of the shoulder outer ring 142 has a second anti-retraction surface that mates with the first anti-retraction surface. The second end of the shoulder outer ring has a guide slope that mates with the arc-shaped guide slope when inserted.

[0053] The background suppression photoelectric sensor provided in this embodiment has a rod-shaped body of the adjustment knob with a shoulder outer ring 142. When the shoulder outer ring passes through the positioning part, due to the large width of the shoulder outer ring, it exerts a squeezing force on the positioning part, causing the elastic arm to expand outward. After the shoulder outer ring passes through, the elastic arm retracts inward under the action of elastic restoring force, thereby positioning the adjustment knob, which is simple to operate. The positioning part of the elastic arm has a first anti-retraction surface, and the shoulder outer ring of the adjustment knob has a second anti-retraction surface that cooperates with the first anti-retraction surface. After the shoulder outer ring passes through the positioning part, the cooperation of the first anti-retraction surface and the second anti-retraction surface can prevent the adjustment knob from falling off. Due to the blocking effect of the first anti-retraction surface, the adjustment knob will not be pulled out from the positioning part.

[0054] In this embodiment, the elastic arm 113 may also be provided with an elastic lug 1132 extending outward from the elastic arm. The elastic lug 1132 is disposed opposite to the positioning part 1131, and the two are respectively disposed on the inner and outer sides of the elastic arm. Inside the housing 1 of the photoelectric sensor, such as... Figure 13 As shown, the elastic lug 1132 can be locked in the inner cavity of the housing 1 and apply a certain pressure to the inner side of the elastic arm 113 so that the positioning surface B of the positioning part 1131 clamps the rod-shaped body of the adjustment knob 14, thereby facilitating the stability of the adjustment knob.

[0055] In this embodiment, the receiving lens can be a split-type receiving lens, which includes a lens element 13 and a lens mount 12. The lens mount 12 is slidably disposed on the support body; the lens element 13 is snapped onto the lens mount 12, and the threaded structure is provided on the lens mount 12. By using this split-type receiving lens, the movable part with a relatively complex structure and the lens element can be manufactured separately, ensuring the simplicity of the lens element structure and thus improving the manufacturing precision of the lens element.

[0056] In this embodiment, the hollow frame of the lens holder 11 has guide rails 115 on both side walls; the lens seat 12 has a slide block 121 that slides with the guide rails 115. The guide rails 115 are elongated guide rails with a generally curved cross-section, and the slide block 121 has an elongated groove structure that matches the guide rail. This arrangement allows the lens seat 12 to slide stably within the lens holder 11. Further, as... Figure 7 and Figure 8As shown, the lens mount 12 is provided with a drive sleeve 124, and the drive sleeve 124 has a threaded structure inside; the hollow frame is also provided with a support block 112, which is disposed inside the base of at least two of the elastic arms 113; the upper part of the support block 112 supports the drive sleeve 124. By the support block 112 disposed on the outside of the lens mount abutting against the drive sleeve 124, the bottom of the lens mount is supported, which can ensure the stable sliding of the lens mount 12 within the lens bracket.

[0057] In this embodiment, as Figure 5-7 As shown, the lens mount 12 has a lens bearing surface, at least one limiting protrusion 123, and several latches 122. The limiting protrusion and latches are all disposed around the lens bearing surface and extend upwards. However, this is not a limitation of the embodiments of the present invention. In this embodiment, there is one limiting protrusion 123 used for limiting the front-to-back position of the lens element. There are four latches 122, arranged at the four corners of the lens mount 12. The lens element 13 has a light-transmitting portion 131, which is a convex lens structure. The edge of the lens element has a limiting groove 133 that cooperates with the limiting protrusion, and a locking portion 132 that engages with the latches. The four latches are used for limiting the left-to-right and longitudinal positions of the lens element. The latches cooperate with the limiting protrusion to achieve precise positioning of the lens element.

[0058] In this embodiment, as Figure 4 As shown, the housing 1 has a emitting lens mounting frame, and the emitting lens 19 is embedded in the mounting frame; at least one of the emitting lens 19 and the inner wall of the mounting frame is provided with a plurality of limiting ribs 102; however, this is not a limitation of the embodiments of the present invention. In this embodiment, a plurality of limiting ribs 102 are arranged inside the mounting frame and located around the emitting lens. The lens bracket 11 is disposed on one side of the emitting lens mounting frame, and the lens element 13 of the receiving lens is obliquely disposed toward one side of the emitting lens. Specifically, as Figure 7 As shown, the frame of the lens mount 12 has a structure that tilts to one side. This tilted arrangement of the lens ensures that the received light enters perpendicularly as much as possible, facilitating focusing and thus improving detection accuracy.

[0059] In this embodiment, as Figure 4 and Figure 5 As shown, the inner wall of the photoelectric sensor housing 1 is provided with a plurality of abutment ribs 101, which support the lens bracket 11 to improve the stability of the lens bracket within the housing.

[0060] In this embodiment, as Figure 2-3 and Figure 11As shown, the photoelectric sensor housing 1 also contains two circuit boards, specifically a first circuit board 15 and a second circuit board 16. The first circuit board 15 is disposed on the back side of the lens bracket 11. Specifically, the first circuit board can be supported by the support post 114 on the back side of the lens bracket. Figure 9 The first circuit board 15 has a receiver 152 and a light-emitting element 151 on its working surface, which are respectively positioned to correspond to the receiving lens and the emitting lens. The second circuit board 16 is disposed on the back side of the first circuit board 15 and is parallel to it. The second circuit board 16 is electrically connected to the first circuit board 15. Specifically, the two circuit boards can be connected by an electrical connection plate 17 disposed on one side of each other, which does not occupy additional internal space of the housing. Furthermore, this embodiment uses two parallel circuit boards, which can fully utilize the internal space of the sensor housing and accommodate more components without increasing the sensor's size.

[0061] In this embodiment, as Figure 13 As shown, the photoelectric sensor housing has multiple guide ribs 103 and multiple positioning posts 104 inside. However, this is not a limitation on the implementation of the present invention. In this embodiment, there are four guide ribs 103, which abut against the outer wall of the lens bracket 11 at the four corners to limit the circumferential position of the lens bracket. The top of the guide ribs 104 can be selected to have a chamfered structure, which can be used to guide the installation of the lens bracket 11 during assembly, improving assembly convenience. The positioning posts 104 pass through the first circuit board 15 or the second circuit board 16 and can be connected to the circuit board through which they pass by a fusion-fixing method. Specifically, as Figure 13 As shown, in this embodiment, the positioning post 104 is provided with 4 posts, of which the post located at... Figure 13 The three positioning posts 104 on the left side pass through the first positioning hole 153 of the first circuit board 15, as shown. Figure 3 As shown, this is to improve the stability of the first circuit board, thereby ensuring the precise positioning of the first circuit board having the receiver and the light-emitting element. Figure 2 and Figure 13 As shown, located Figure 13 The rightmost positioning post 104 passes through the second positioning hole 161 located on the left side of the second circuit board. The rightmost positioning post is also located on the outside of the first circuit board and will not affect the installation of the first circuit board. Furthermore, the right side of the second circuit board 16 can abut against the support structure inside the housing 1 to ensure the stable installation of the second circuit board.

[0062] In this embodiment, to ensure that the signals of the two circuit boards do not interfere with each other, a shielding circuit board can be provided between the first circuit board and the second circuit board. The shielding circuit board is preferably an FPC. Additionally, as... Figure 12 As shown, within the housing of the background suppression photoelectric sensor provided in this embodiment, a shielding sheet 18 may also be provided. The shielding sheet 18 has a base plate and two side plates. The two side plates extend upward from the base plate and are located on both sides of the first circuit board and the second circuit board. The shielding sheet is preferably a copper sheet. The base plate covers at least a portion of the working surface of the first circuit board 151, and a through slot is provided at the position corresponding to the receiver on the base plate to ensure that the receiver 152 of the first circuit board 151 is not obstructed.

[0063] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. A background suppression photoelectric sensor comprising a housing and a light receiving module disposed within the housing, the light receiving module comprising an adjustment knob, a receiving lens, and a lens holder for supporting the receiving lens and the adjustment knob, characterized in that, The lens holder includes: The bracket body has a hollow frame, and the bracket body is adapted to support the receiving lens; At least two elastic arms extend outward from an outer side wall of the support body. Each elastic arm has a positioning portion extending inward, and the top of the positioning portion has a positioning surface. The positioning surfaces of each elastic arm cooperate with each other to support the adjustment knob. The positioning surface is an arc-shaped positioning surface. The side of the positioning portion facing the support body has a first anti-reverse surface, and the side of the positioning portion facing away from the support body has an arc-shaped guide slope. The arc-shaped positioning surface is connected to the first anti-reverse surface and the arc-shaped guide slope, respectively. The adjustment knob has a rod-shaped body located between the positioning surfaces of the elastic arm; the rod-shaped body has a shoulder outer ring in the middle, the first end of the shoulder outer ring has a second anti-retraction surface that cooperates with the first anti-retraction surface, and the second end of the shoulder outer ring has a guide slope that cooperates with the arc-shaped guide slope when inserted.

2. The background suppression photodetector of claim 1, wherein, The elastic arm also has an elastic lug extending outward from the elastic arm, and the elastic lug is disposed opposite to the positioning part.

3. The background suppression photoelectric sensor according to claim 1, characterized in that, It also includes a light emitting module disposed within the housing, and the light receiving module further includes a receiver. The light emitting module includes a light-emitting element and a emitting lens.

4. The background suppression photoelectric sensor according to claim 3, characterized in that, The end of the rod-shaped body is threaded; the receiving lens has a threaded structure that mates with the thread at the end of the rod-shaped body.

5. The background suppression photoelectric sensor according to claim 4, characterized in that, The receiving lens includes a lens element and a lens mount, with the lens mount slidably mounted on the support body; the lens element is snapped onto the lens mount, and the threaded structure is provided on the lens mount.

6. The background suppression photoelectric sensor according to claim 5, characterized in that, The hollow frame has guide rails inside its two side walls; the lens mount has a slide block that slides with the guide rails.

7. The background suppression photoelectric sensor according to claim 5, characterized in that, The lens mount is provided with a drive sleeve, and the drive sleeve is provided with the threaded structure; the hollow frame is also provided with a support block, which is disposed on the inner side of the base of at least two of the elastic arms; the upper part of the support block supports the drive sleeve.

8. The background suppression photoelectric sensor according to claim 7, characterized in that, The lens mount has a lens bearing surface, at least one limiting protrusion, and several buckles. The limiting protrusion and buckles are all arranged around the lens bearing surface and extend upward. The edge of the lens sheet has a limiting groove that cooperates with the limiting protrusion and a snap-fit ​​portion that engages with the buckles.

9. The background suppression photoelectric sensor according to claim 5, characterized in that, The housing has a emitting lens mounting frame, and the emitting lens is embedded in the mounting frame; at least one of the emitting lens and the inner wall of the mounting frame is provided with a plurality of limiting ribs.

10. The background suppression photoelectric sensor according to claim 9, characterized in that, The lens bracket is disposed on one side of the transmitting lens mounting frame, and the lens element of the receiving lens is offset toward one side of the transmitting lens.

11. The background suppression photoelectric sensor according to claim 1, characterized in that, The inner wall of the housing is provided with a plurality of abutment ribs, which support the lens bracket.

12. The background suppression photoelectric sensor according to claim 3, characterized in that, It also includes, A first circuit board, wherein the receiver and the light-emitting element are provided on the working surface of the first circuit board, and the receiver and the light-emitting element are respectively arranged corresponding to the receiving lens and the emitting lens; And a second circuit board electrically connected to the first circuit board, the second circuit board being disposed on the back side of the first circuit board and disposed parallel to the first circuit board.

13. The background suppression photoelectric sensor according to claim 12, characterized in that, The housing contains, The guide ribs are multiple in number and abut against the outer wall of the lens bracket; The positioning posts, which are multiple in number, pass through the first or second circuit board and are fixedly connected to the circuit board through which they pass.

14. The background suppression photoelectric sensor according to claim 12, characterized in that, A shielding circuit board, which is an FPC, is also provided between the first circuit board and the second circuit board.

15. The background suppression photoelectric sensor according to claim 12, characterized in that, It also includes a shielding sheet having a base plate and two side plates; the two side plates extend upward on the base plate and are located on both sides of the first circuit board and the second circuit board; the shielding sheet is a copper sheet.

16. The background suppression photoelectric sensor according to claim 15, characterized in that, The base plate covers at least a portion of the working surface of the first circuit board, and the base plate has a through slot at the position corresponding to the receiver.

Images