A novel photoelectric sensor

Abstract

The utility model relates to a novel photoelectric sensor belongs to photoelectric detection technical field, including casing, light source, photoelectric detector and setting optical assembly in the front of light source and photoelectric detector, its characterized in that, the light source is provided with the emission hole, the photoelectric detector is provided with the receiving hole, the center distance d of emission hole and receiving hole satisfies: d<=10mm, the aperture Phi 1 of emission hole and the aperture Phi 2 of receiving hole are all not more than 3mm, the included angle theta between the light of light source emission and the light of photoelectric detector after entering after the reflection of target <=15 DEG. By reducing the distance of light source and detector, reducing the aperture size, the center distance of light source emission hole and photoelectric detector receiving hole is not more than 5mm, both aperture is not more than 1.5mm, the light emission and reflection included angle is not more than 15 DEG, significantly improve the detection consistency and precision, solve the problem of the included angle big, false alarm rate high in the prior art, and cooperate with light intensity control and signal processing, can significantly improve the detection precision and reliability.

Description

Technical Field

[0001] This utility model relates to the field of photoelectric detection technology, and to a novel photoelectric sensor. Background Technology

[0002] A photoelectric sensor is an electronic device that uses the photoelectric effect to convert light signals into electrical signals. It is widely used in automatic control, detection and other fields. Its working principle revolves around the core of "photoelectric conversion": First, a light signal of a specific wavelength is emitted by a built-in light source (such as an LED or laser diode), which is focused by an optical lens and directed towards the target being measured. If the target is present, the light will be reflected or transmitted (depending on the scene), and the remaining light signal will be received by a photodetector (such as a photoresistor or photodiode). The detector converts the change in light intensity into a weak change in current or voltage, which is then amplified and filtered by the signal processing circuit, and finally outputs an electrical signal (such as a switch or analog signal) that can be recognized by the device, thus realizing the detection, counting, or positioning of the target. The significance of photoelectric sensors is great. They break through the limitations of traditional mechanical detection: non-contact measurement avoids damage to the object being measured, microsecond-level response adapts to high-speed production lines, and is resistant to electromagnetic interference. They can work stably in harsh environments such as high temperature and dust. From parts counting and packaging inspection on industrial production lines to adaptive brightness of mobile phone screens in consumer electronics, to infrared alarms in security and pulse monitoring in medical care, their applications span multiple fields, providing a key "visual organ" for the development of automation and intelligence, and are an indispensable part of modern electronic systems. According to CN101858758B, a "photoelectric sensor" is disclosed. This technology discloses "an output circuit including first and second photodetectors; first and second receiving lenses respectively positioned adjacent to the first and second photodetectors; and a support structure for mutually supporting each of the light source, each photodetector, and each receiving lens. If the target is at a predetermined position, a first portion of the emitted light is reflected by the target and received by the first photodetector after passing through the first receiving lens, and a second portion of the emitted light is reflected by the target and received by the second photodetector after passing through the second receiving lens. Furthermore, the output circuit generates an output signal indicating the sensing characteristics of the target based on the signals generated by the first and second photodetectors in response to the partial light received by each photodetector." However, the detection accuracy of photoelectric sensors is closely related to the angle between the light source and the detector. When the angle is too large, the beam diverges severely, the detection consistency is poor, and it is easily affected by ambient light. The above technical solution expands the detection range through two detection channels, but the optical path angle is relatively large (usually greater than 30°). When detecting close-range or high-reflectivity targets, it is easy to generate false alarms or missed alarms, thus limiting the detection accuracy. To address the aforementioned problems, this application proposes a novel photoelectric sensor. Utility Model Content

[0003] This utility model addresses the technical problems existing in the prior art by providing a novel photoelectric sensor.

[0004] The technical solution of this utility model to solve the above-mentioned technical problems is as follows: A novel photoelectric sensor includes a housing, a light source, a photoelectric detector, and an optical component disposed in front of the light source and the photoelectric detector. The light source is provided with an emission hole, and the photoelectric detector is provided with a receiving hole. The center distance d between the emission hole and the receiving hole satisfies the following conditions: d≤10mm, the aperture Φ1 of the emission hole and the aperture Φ2 of the receiving hole are both not greater than 3mm, and the angle θ between the light emitted by the light source and the light that enters the photoelectric detector after being reflected by the target is ≤15°.

[0005] Preferably, the photoelectric sensor further includes a light intensity control circuit, which includes an adjustable current source and a light feedback loop.

[0006] By setting up a light intensity control circuit, the emitted light intensity of the light source can be controlled within the range of 0.5-2mW, which is used to adjust the emitted power of the light source in real time.

[0007] Preferably, a substrate is fixedly connected inside the housing, and the light source and photodetector are integrated on the same substrate, with a center distance d between the light source and the photodetector of 3 to 4 mm.

[0008] Preferably, the aperture diameter Φ1 of the transmitting hole and the aperture diameter Φ2 of the receiving hole are both 0.8 to 1.2 mm.

[0009] Preferably, the optical component includes a composite lens, which includes an emitting region and a receiving region, and the optical axis spacing between the emitting region and the receiving region matches the center distance d between the light source and the photodetector.

[0010] Preferably, the emitting and receiving areas of the composite lens are designed with aspherical surfaces.

[0011] By using an aspherical design for the transmitting and receiving areas, optical aberrations are effectively reduced.

[0012] Preferably, the photoelectric sensor further includes a signal processing circuit.

[0013] By setting up a signal processing circuit, the signal output by the photodetector is logarithmically amplified and threshold compared, thereby improving the detection signal-to-noise ratio.

[0014] Preferably, a cover plate is fixedly connected to the outer side of the composite lens. The cover plate is provided with two symmetrically distributed buckle assemblies. The buckle assembly includes an arc-shaped buckle block, a sliding column, and a spring. The lower end of the arc-shaped buckle block is fixedly connected to the sliding column. The sliding column passes through the inside of the spring and is fixedly connected to the cover plate. The upper end of the spring is fixedly connected to the arc-shaped buckle block. The lower end of the spring is fixedly connected to the cover plate. The inside of the housing is provided with a buckle groove that is adapted to the arc-shaped buckle block.

[0015] By incorporating snap-fit ​​components, the installation and opening of the housing and cover are facilitated, thereby improving maintenance efficiency.

[0016] Preferably, a guide rod is fixedly connected to the cover plate, and a slot is provided inside the housing, with the guide rod being adapted to the slot.

[0017] By setting guide rods and slots, alignment is made easier during the installation of the cover plate, and relative shaking after installation is prevented, thus improving the stability of the equipment.

[0018] The beneficial effects of this utility model are: A high-precision photoelectric sensor includes a housing, a light source, a photodetector, and optical components. By optimizing the optical path structure and control strategy, the center distance between the light source's emitting aperture and the photodetector's receiving aperture is no greater than 5 mm, the aperture diameter of both is no greater than 1.5 mm, and the angle between light emission and reflection is no greater than 15°. Using a light intensity control circuit, the light intensity emitted by the light source is controlled within the range of 0.5-2 mW, and the optical path angle is ≤15°, significantly improving detection consistency and accuracy. This solves the problems of large angles and high false alarm rates in existing technologies. At the same time, the small aperture design reduces stray light and ambient light interference, and the light intensity is controllable, thus adapting to targets with different reflectivities and avoiding saturation or insufficient signal. Furthermore, the structure is compact, easy to integrate and install, and suitable for industrial scenarios with high precision and high reliability requirements. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the overall structure of this utility model; Figure 2 This is a schematic diagram of the internal structure of the present invention; Figure 3 This is a schematic diagram of the composite lens structure of this utility model; Figure 4 This is a partial structural cross-sectional view of the present utility model.

[0020] The attached diagram lists the components represented by each number as follows: 1. Housing; 2. Light source; 3. Photodetector; 4. Compound lens; 5. Emitting area; 6. Receiving area; 7. Emitting aperture; 8. Receiving aperture; 9. Light intensity control circuit; 10. Substrate; 11. Signal processing circuit; 12. Cover plate; 13. Guide rod; 14. Slot; 15. Arc-shaped locking block; 16. Sliding column; 17. Spring; 18. Slot. Detailed Implementation

[0021] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model. Example

[0022] Reference Figure 1-4 A novel photoelectric sensor includes a housing 1, a light source 2, a photodetector 3, and an optical component positioned in front of the light source 2 and the photodetector 3. The light source 2 has an emission aperture 7, and the photodetector 3 has a receiving aperture 8. The center distance d between the emission aperture 7 and the receiving aperture 8 satisfies the following conditions: d ≤ 10 mm; the aperture diameter Φ1 of the emission aperture 7 and the aperture diameter Φ2 of the receiving aperture 8 are both no greater than 3 mm; the angle θ between the light emitted by the light source 2 and the light reflected from the target and entering the photodetector 3 is ≤ 15°. The photoelectric sensor also includes a light intensity control circuit 9, which includes an adjustable current source and a light feedback loop. By setting the light intensity control circuit 9, the emitted light intensity of the light source 2 can be controlled within the range of 0.5-2 mW for real-time adjustment of the light source's emission power. The light source 2 is an infrared laser diode with a wavelength range of 850-940 nm. The photoelectric sensor also includes a signal processing circuit 11, which performs logarithmic amplification and threshold comparison on the signal output by the photodetector, thereby improving the detection signal-to-noise ratio.

[0023] Reference Figure 2 and Figure 3 The housing 1 has a fixedly connected substrate 10 inside. The light source 2 and the photodetector 3 are integrated on the same substrate 10. The center distance d between the light source 2 and the photodetector 3 is 3 to 4 mm. The aperture Φ1 of the emission hole 7 and the aperture Φ2 of the receiving hole 8 are both 0.8 to 1.2 mm.

[0024] Reference Figure 1-3The optical components include a compound lens 4, which includes an emitting region 5 and a receiving region 6. The optical axis spacing between the emitting region 5 and the receiving region 6 matches the center distance d between the light source and the photodetector. The emitting region 5 and the receiving region 6 of the compound lens 4 are aspherical. By using an aspherical design for the emitting region 5 and the receiving region 6, optical aberrations are effectively reduced. A cover plate 12 is fixedly connected to the outer side of the compound lens 4. The cover plate 12 is provided with two symmetrically distributed latching components. The latching components include an arc-shaped latch 15, a sliding post 16, and a spring 17. The lower end of the arc-shaped latch 15 is fixedly connected to the sliding post 16. The sliding post 16 passes through the inside of the spring 17 and is fixedly connected to the cover plate 12. The upper end of the spring 17 is fixedly connected to the arc-shaped latch 15, and the lower end of the spring 17 is fixedly connected to the cover plate 12. 12. Fixed connection: The housing 1 has a slot 18 inside, which is adapted to the arc-shaped block 15. By setting the buckle assembly, the installation and opening of the housing 1 and the cover 12 are facilitated, improving maintenance efficiency. A guide rod 13 is fixedly connected to the cover 12. The housing 1 has a slot 14 inside, which is adapted to the guide rod 13. By setting the guide rod 13 and the slot 14, it is convenient to align the cover 12 during installation and prevent relative shaking after installation, thus improving the stability of the equipment.

[0025] Working principle: In use, reduce the center distance between the emission aperture 7 of the light source 2 and the receiving aperture 8 of the photodetector 3 to less than 10mm, control the aperture of the emission aperture 7 and the aperture of the receiving aperture to within 3mm, adjust the layout of the optical components so that the angle between light emission and reflection is no greater than 15°, use the light intensity control circuit 9 to control the light intensity emitted by the light source 2 within the range of 0.5-2mW, and then use the signal processing circuit 11 to filter and threshold the detection signal using the signal processing algorithm, and perform aspherical optimization on the emission area and receiving area of ​​the composite lens 4 to further reduce optical errors. During installation, simply align the guide rod 13 with the slot 14 in the housing 1. During the process of pushing the cover plate 12 in, the arc-shaped locking block 15 is squeezed by the inner wall of the housing 1 and is locked into the slot 18 under the action of the spring 17 to achieve installation. The operation is simple and convenient. Disassembly only requires pressing down the two arc-shaped locking blocks 15 and pulling out the cover plate 12, which is convenient for maintenance.

[0026] The above description is merely a preferred embodiment of the present utility model and is not intended to limit the present utility model in any other way. Any person skilled in the art may make changes or modifications to the above-disclosed technical content to create equivalent embodiments for application in other fields. However, any simple modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of the present utility model without departing from the technical solution of the present utility model shall still fall within the protection scope of the technical solution of the present utility model.

Claims

1. A novel photoelectric sensor, comprising a housing (1), a light source (2), a photodetector (3), and an optical assembly disposed in front of the light source (2) and the photodetector (3), characterized in that, The light source (2) is provided with an emission hole (7), and the photodetector (3) is provided with a receiving hole (8). The center distance d between the emission hole (7) and the receiving hole (8) satisfies the following conditions: d ≤ 10 mm. The aperture Φ1 of the emission hole (7) and the aperture Φ2 of the receiving hole (8) are both no greater than 3 mm. The angle θ between the light emitted by the light source (2) and the light that enters the photodetector (3) after being reflected by the target is ≤ 15°.

2. The novel photoelectric sensor according to claim 1, characterized in that, The photoelectric sensor also includes a light intensity control circuit (9), which includes an adjustable current source and a light feedback loop.

3. The novel photoelectric sensor according to claim 1, characterized in that, The housing (1) is fixedly connected to a substrate (10), and the light source (2) and photodetector (3) are integrated on the same substrate (10). The center distance d between the light source (2) and the photodetector (3) is 3-4 mm.

4. The novel photoelectric sensor according to claim 1, characterized in that, The aperture diameter Φ1 of the transmitting hole (7) and the aperture diameter Φ2 of the receiving hole (8) are both 0.8 to 1.2 mm.

5. A novel photoelectric sensor according to claim 1, characterized in that, The optical component includes a composite lens (4), which includes an emitting region (5) and a receiving region (6). The optical axis spacing between the emitting region (5) and the receiving region (6) matches the center distance d between the light source and the photodetector.

6. A novel photoelectric sensor according to claim 1, characterized in that, The emission area (5) and receiving area (6) of the composite lens (4) are designed with aspherical surfaces.

7. A novel photoelectric sensor according to claim 1, characterized in that, The photoelectric sensor also includes a signal processing circuit (11).

8. A novel photoelectric sensor according to claim 1, characterized in that, The outer side of the composite lens (4) is fixedly connected to a cover plate (12). The cover plate (12) is provided with two symmetrically distributed buckle assemblies. The buckle assembly includes an arc-shaped buckle block (15), a sliding column (16) and a spring (17). The lower end of the arc-shaped buckle block (15) is fixedly connected to the sliding column (16). The sliding column (16) passes through the inside of the spring (17) and is fixedly connected to the cover plate (12). The upper end of the spring (17) is fixedly connected to the arc-shaped buckle block (15). The lower end of the spring (17) is fixedly connected to the cover plate (12). The inside of the housing (1) is provided with a slot (18), which is adapted to the arc-shaped buckle block (15).

9. A novel photoelectric sensor according to claim 8, characterized in that, A guide rod (13) is fixedly connected to the cover plate (12), and a slot (14) is provided inside the housing (1). The guide rod (13) is adapted to the slot (14).

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