Light barrier

Abstract

A light barrier comprising a faceplate (1) having a window portion (10), a holder (2) pivotally connected to the faceplate (1) about a first axis (V), an optical transmitter (3) arranged on the holder (2) and allowing a light beam to pass through the window portion (10), and first adjustment means (4; 40) for adjusting the relative angular orientation between the faceplate (1) and the holder (2), wherein the faceplate (1) has a first through-hole (11) through which the first adjustment means (4; 40) is accessible.

Description

[Technical Field]

[0001] The present invention relates to light barriers, and in particular to built-in light barriers. [Background technology]

[0002] In conventional built-in light barriers, i.e., light barriers integrated into the housing, the direction of the light beam is checked after the light transmitter is installed. If it is off target, the transmitter must be removed to adjust the light beam's output angle. Therefore, correctly installing the light transmitter requires a skilled worker or several repetitions. This applies to through-beam light barriers and reflective light barriers. In either case, correct orientation of such built-in light barriers is tedious. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] US Patent Application Publication No. 2021 / 405157 Summary of the Invention [Problem to be solved by the invention]

[0004] The object of the present invention is to provide a light barrier, the light beam of which can be easily adjusted in the field when integrated into an essentially closed housing. [Means for solving the problem]

[0005] This problem is solved by a light barrier having the features of claim 1. Further embodiments of the light barrier and the light barrier device are defined by the features of the further claims.

[0006] The light barrier according to the present invention comprises a faceplate having a window portion, a holder pivotally connected to the faceplate about a first axis, an optical transmitter arranged on the holder and allowing a light beam to pass through the window portion, and a first adjustment means capable of adjusting the relative angular orientation between the faceplate and the holder, wherein the faceplate has a first through-hole and the first adjustment means is accessible through the first through-hole.

[0007] Such a design has the advantage that the light beam of the light barrier can be adjusted in the field, i.e. when installed in an essentially closed housing that does not provide access to the light transmitter from the side or back to adjust the light beam direction.

[0008] The window is made of a material that is translucent to the light beam, and the first through hole is sized to allow a tool such as a screwdriver or socket wrench to be inserted therethrough.

[0009] In one embodiment, the faceplate includes a first reception on a side of the faceplate facing the holder and aligned with the first through-hole. The holder includes a second reception aligned with the first reception in an undeflected state. A first end of the first adjustment means is disposed in the first reception, and a second end of the first adjustment means is disposed in the second reception. The receptions may be separate components, or the first reception may be formed as a single component integral with the faceplate, and / or the second reception may be formed as a single component integral with the holder. After actuation of the first adjustment means, the holder is deflected and has an angular deviation from an initial undeflected state. The holder can be deflected relative to the faceplate in a first direction and a second direction opposite the first direction. Actuation of said first adjustment means may be achieved by rotating at least a portion thereof or by pushing or pulling at least a portion thereof.

[0010] In one embodiment, the first adjusting means comprises a first screw and a corresponding first nut. The head of the first screw is located in the first receiving portion, and the first nut is located in the second receiving portion. The adjustment means can be activated by accessing the head of the screw with a corresponding tool. This design allows the screw to be used with any type of screw drive. Preferably, a non-external drive is used, as the corresponding tool dimensions are smaller. For example, a slotted, cross, square, multi-square, internal hexagon, pentagon, hexagon, or a combination thereof, can be used.

[0011] In one embodiment, the faceplate includes at least one pin disposed in at least one complementary third through hole of the holder, forming a pivotable connection between the faceplate and the holder. The at least one pin may be a separate component or may be integrally formed as a single component with the faceplate. It is possible to have two coaxial pins whose axial distance is less than the thickness of the holder surrounding the third through hole. An end face of the at least one pin may be beveled, resulting in a pin whose height increases as the distance from the optical transmitter increases. The third through hole of the holder and the at least one beveled pin of the faceplate together form a snap connection.

[0012] In one embodiment, the faceplate includes a slot on a side of the faceplate facing the holder, the at least one pin protruding at least partially into the slot, and the holder is disposed with a portion of the holder within the slot that includes the at least one third through hole. If there are two pins, they protrude into the slot from opposite sides.

[0013] In one embodiment, the holder comprises a front portion connected to the faceplate and a rear portion in which an optical transmitter is arranged, the rear portion being pivotally connected to the front portion about a second axis. The pivotable connection between the front and rear portions, acting like a hinge, may be a separate part or may be formed integrally with the front and / or rear portions in a single part. The holder comprises second adjustment means for adjusting the relative angular orientation between the front and rear portions. A second through-hole is provided in the faceplate, through which the second adjustment means is accessible for adjustment.

[0014] In one embodiment, the front portion of the holder includes a third receptacle that aligns with the second through-hole in the faceplate in an undeflected state. The rear portion of the holder includes a fourth receptacle that aligns with the third receptacle in an undeflected state. A first end of the second adjustment means is disposed in the third receptacle, and a second end of the second adjustment means is disposed in the fourth receptacle. The third receptacle and the fourth receptacle may be separate entities, or the third receptacle and the front portion may be integrally formed, and / or the fourth receptacle and the rear portion may be integrally formed.

[0015] In one embodiment, the second adjusting means comprises a second screw and a corresponding second nut, the head of the second screw being located in the third receiving portion and the second nut being located in the fourth receiving portion. The second screw can be the same as the first screw or can have the same diameter but a different length. The second nut can be the same as the first nut.

[0016] In one embodiment, the front and rear portions of the holder are integrally formed in a single piece and their connection includes a material thinning that forms a hinge. Alternatively or additionally, the hinge comprises a perforation.

[0017] In one embodiment, the window is integrally formed with the other surface of the faceplate, alternatively, the window may be a separate inserted component.

[0018] In one embodiment, the first through-hole is located in a first opaque portion of the faceplate adjacent to the window. Additionally or alternatively, the second through-hole is located in a second opaque portion of the faceplate opposite the first opaque portion and adjacent to the window. The opaque portion can be created by sandblasting or other surface roughening process.

[0019] In one embodiment, the faceplate comprises at least one retainer located on a side of the faceplate, i.e. on any one of its sides, which retainer is designed to form a snap connection with the housing in its installed position, e.g., an essentially closed profile, when the light barrier is installed.

[0020] In one embodiment, at least one first retainer is disposed on a first side of the faceplate and at least one second retainer is disposed on a second side of the faceplate opposite the first side, and in an installed state, the retainers can be disposed vertically or horizontally.

[0021] The window or the window combined with the faceplate can be made from a transparent thermoplastic polymer such as polycarbonate, and the holder can be made from a thermoplastic polymer such as polypropylene. The faceplate and / or the holder can be manufactured by injection molding.

[0022] The features of the light barrier embodiments described above may be used in any combination provided they do not contradict each other.

[0023] A light barrier installation comprises a light barrier according to any of the above embodiments and a light receiver or a light reflector arranged in an area that can be irradiated by the light beam of the light transmitter, i.e., the light beam hits the light receiver or the light reflector when the switch is turned on.

[0024] In one embodiment, the light barrier is disposed within a housing, with a surface of the faceplate of the light barrier being substantially flush with a surface of the housing on which the light barrier is disposed. [Brief explanation of the drawings]

[0025] [Figure 1] 1 is a perspective view of a light barrier according to the present invention; [Figure 2] FIG. 2 is a top view of the light barrier of FIG. 1 with perpendicular light beam directions. [Figure 3] FIG. 2 is a top view of the light barrier of FIG. 1 with a horizontally polarized light beam. [Figure 4] 2 is a cross-sectional view through a vertical central plane of the light barrier of FIG. 1; [Figure 5] FIG. 2 is a perspective view of the light barrier of FIG. 1 in situ. DETAILED DESCRIPTION OF THE INVENTION

[0026] Embodiments of the present invention are described in more detail below with reference to the drawings, which are for illustrative purposes only and should not be construed as limiting.

[0027] FIG. 1 shows a perspective view of a light barrier according to the present invention, and FIG. 2 shows a top view of the light barrier of FIG. 1 with a perpendicular light beam direction. The light barrier comprises a faceplate 1 having a window 10 transparent to the light beam of an installed light transmitter 3. On either side of the window 10, a first opaque section consisting of a first through-hole 11 and a second opaque section consisting of a second through-hole 12 are provided. Two first retainers 14 are arranged on the upper side of the faceplate 1, and two second retainers 15 are arranged on the lower side. A holder 2 is pivotally connected to the faceplate 1 about a first axis V. The illustrated first axis V is a vertical axis, allowing the holder 2 to pivot relative to the faceplate 1 in a horizontal plane. The holder 2 comprises a front part 20 connected to the faceplate 1 and a rear part 21 in which the light transmitter 3 is arranged by means of a hook-shaped retainer 210 and a fixing pin 211. The front section 20 and the rear section 21 are plate-shaped. The rear section 21 is rotatably connected to the front section 20 about a second axis H. The illustrated second axis H is a horizontal axis, allowing the rear section 21 to pivot relative to the front section 20 in a vertical plane. The faceplate 1 includes a first receiving portion 13 aligned with the first through-hole 11 and in which the head of the first adjusting screw 4 is disposed. The first receiving portion 13 is open at the top and has a slot on the side opposite the faceplate 1 that allows the head of the first adjusting screw 4 to be inserted from the top. The first receiving portion 13 extends from the faceplate 1 toward the holder 2. The screw drive portion of the first adjusting screw 4 is accessible with a tool through the first through-hole 11. The front section 20 of the holder 2 includes a second receiving portion 23 aligned with the first receiving portion 13 in the illustrated unflexed state, in which a first adjusting nut 40 is disposed. The front portion 20 is provided with a third receiving portion 24 which is aligned with the second through-hole 12 in the illustrated unflexed state and in which the head of the second adjusting screw 5 is disposed. The second receiving portion 23 and the third receiving portion 24 extend upward from the plate of the front portion 20. The second receiving portion 23 is open at its top and has a slot on the side facing the face plate 1 to allow for the top insertion of the first adjusting nut 40.The third receiving portion 24 is open at its top and has a slot on the side opposite the faceplate 1 to allow for top insertion of the head of the second adjusting screw 5. The screw drive portion of the second adjusting screw 5 is accessible with a tool via the second through-hole 12. The rear portion 21 of the holder 2 has a fourth receiving portion 25 that is aligned with the third receiving portion 24 in the illustrated unflexed state, and has a second adjusting nut 50 disposed therein. The fourth receiving portion 25 extends upward from the plate of the rear portion 21. The fourth receiving portion 25 is open at its top and has a slot on the side facing the faceplate 1 to allow for top insertion of the second adjusting nut 50.

[0028] Figure 3 shows a top view of the light barrier of Figure 1 with a horizontally deflected light beam. To achieve such deflection, the drive of the first adjusting screw 4 is accessed through the first through-hole 11 with a tool and rotated counterclockwise. The head of the first adjusting screw 4 is held in the first receiving portion 13 of the faceplate 1, and the first adjusting nut 40 is held in the second receiving portion 23 of the front part 20 of the holder 2, which is pivotally connected to the faceplate 1 about the first axis V, so that the holder 2 pivots clockwise about the vertical axis V. As a result, rotating the first adjusting screw 4 clockwise rotates the holder 2 counterclockwise about the vertical axis V.

[0029] FIG. 4 shows a cross-sectional view of the light barrier of FIG. 1 taken through a vertical center plane. The first retainer 14 is the uppermost protruding part of the faceplate 1, and the second retainer 15 is the lowermost protruding part. A horizontal slot 16 is formed in the lower part of the faceplate 1, i.e., the part not irradiated by the optical beam of the optical transmitter 3, into which the front part 20 of the holder 2 is inserted. A first inclined pin 17 protrudes from the upper part of the slot 16, and a second inclined pin 18 protrudes from the lower part, coaxially with the first pin 17. The pins are disposed in a third through-hole 26 in the front part 20 of the holder. The central axes of the pin and the third through-hole coincide with the vertical axis V. The holder 2 has a plate-shaped front part 20 and a plate-shaped rear part 21, which are connected by a hinge 22 formed by thinning the material. The line of minimum thickness of the thinned material coincides with the horizontal axis H. The head of the second adjusting screw 5 is held in the third receiving portion 24 of the front part 20 of the holder 2, the second adjusting nut 50 is held in the fourth receiving portion 25 of the rear part 21 of the holder 2, and the rear part 21 is pivotally connected to the front part about the second axis H, so that counterclockwise pivoting of the second adjusting screw 5 causes the rear part 21 to pivot downward about the horizontal axis H. Therefore, when the second adjusting screw 5 is rotated clockwise, the rear part 21 pivots upward about the horizontal axis H.

[0030] Figure 5 shows a perspective view of the light barrier of Figure 1 in situ, i.e. built into a housing 6. The housing shown is a profile 6 having a surface 60 on which the light barrier is arranged. Surface 60 is when the profile 6 is flush with the surface of the faceplate 1. For example, such a profile can be part of a transport system. [Explanation of symbols]

[0031] 1 faceplate 10 Window 11 First through hole 12 Second through hole 13 First storage compartment 14 First retainer 15 Second retainer 16 slots 17 First Pin 18 Second Pin 2 holder 20 front 21 Rear 210 Retainer 211 pins 22 Hinge 23 Second storage compartment 24 Third Storage Unit 25 Fourth Storage Unit 26 Third through hole 3 Optical transmitter 4 First Adjustment Screw 40 First Adjustment Nut 5 Second Adjustment Screw 50 Second Adjustment Nut 6 Profile (housing) 60 surface H horizontal axis (second axis) V vertical axis (first axis)

Claims

1. The device comprises a faceplate (1) having a window (10), a holder (2) pivotally connected to the faceplate (1) about a first axis (V), an optical transmitter (3) arranged on the holder (2) and allowing a light beam to pass through the window (10), and first adjusting means (4; 40) for adjusting the relative angular orientation between the faceplate (1) and the holder (2), A light barrier, characterized in that the faceplate (1) is provided with a first through-hole (11), and the first adjusting means (4; 40) are accessible through the first through-hole.

2. 2. The light barrier of claim 1, wherein the faceplate (1) comprises a first receiving portion (13) on a side of the faceplate (1) facing the holder (2) and aligned with the first through-hole (11), and the holder (2) comprises a second receiving portion (23) aligned with the first receiving portion (13) in an undeflected state, and wherein a first end of the first adjusting means (4; 40) is arranged in the first receiving portion (13) and a second end of the first adjusting means (4; 40) is arranged in the second receiving portion (23).

3. 3. A light barrier according to claim 2, wherein the first adjusting means comprises a first screw (4) and a corresponding first nut (40), the head of the first screw (4) being arranged in the first receiving part (13) and the first nut (40) being arranged in the second receiving part (23).

4. 4. A light barrier according to any one of claims 1 to 3, wherein the faceplate (1) is provided with at least one pin (17; 18) arranged in at least one complementary third through-hole (26) of the holder (2) and forming a pivotable connection between the faceplate (1) and the holder (2).

5. 5. The light barrier of claim 4, wherein the faceplate (1) has a slot (16) on a side of the faceplate (1) facing the holder (2), the at least one pin (17; 18) protruding at least partially into the slot (16), and the holder (2) is arranged with a portion within the slot (16) that includes at least one of the third through holes (26).

6. 6. A light barrier according to any one of claims 1 to 5, wherein the holder (2) comprises a front part (20) connected to the faceplate (1) and a rear part (21) in which the optical transmitter (3) is arranged and which is pivotally connected to the front part (20) about a second axis (H), the holder (2) comprising second adjustment means (5; 50) for adjusting the relative angular orientation between the front part (20) and the rear part (21), the faceplate (1) being provided with a second through-hole (12) accessible for adjustment by the second adjustment means (5; 50).

7. 7. The light barrier of claim 6, wherein the front part (20) of the holder (2) comprises a third receiving part (24) that is aligned with the second through-hole (12) of the faceplate (1) in an undeflected state, and the rear part (21) of the holder (2) comprises a fourth receiving part (25) that is aligned with the third receiving part (24) in an undeflected state, and a first end of the second adjusting means (5; 50) is arranged in the third receiving part (24) and a second end of the second adjusting means (5; 50) is arranged in the fourth receiving part (25).

8. 8. A light barrier according to claim 7, wherein the second adjusting means comprises a second screw (5) and a corresponding second nut (50), the head of the second screw (5) being arranged in the third receiving part (24) and the second nut (50) being arranged in the fourth receiving part (25).

9. A light barrier according to any one of claims 6 to 8, wherein the front (20) and rear (21) parts of the holder (2) are integrally formed in a single piece, the connection between them comprising a thinning of material forming a hinge (22).

10. A light barrier according to any one of claims 1 to 9, wherein the window (10) is either integrally formed with the other surface of the faceplate (1) or is a separate part that is inserted into the faceplate (1).

11. 11. A light barrier according to any one of claims 1 to 10, wherein the first through-holes (11) are arranged in a first opaque part of the faceplate (1) adjacent to the window portion (10) and / or the second through-holes (12) are arranged in a second opaque part of the faceplate (1) opposite the first opaque part and adjacent to the window portion (10).

12. A light barrier according to any one of the preceding claims, wherein the faceplate (1) comprises at least one retainer (14; 15) arranged on a side of the faceplate (1).

13. 13. The light barrier of claim 12, wherein at least one first retainer (14) is arranged on a first side of the faceplate (1) and at least one second retainer (15) is arranged on a second side of the faceplate (1) opposite the first side.

14. A light barrier device comprising the light barrier according to any one of claims 1 to 13 and a light receiver or a light reflector arranged in an area that can be irradiated with the light beam of the light transmitter (3).

15. 15. The light barrier device of claim 14, wherein the light barrier is arranged in a housing (6) and the surface of the faceplate (1) of the light barrier is substantially flush with a surface (60) of the housing (6) on which the light barrier is arranged.

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