Optical fiber speed sensor

Abstract

The utility model discloses an optical fiber speed sensor, which belongs to the field of comprehensive protection of universal belt conveyors and comprises a shell, a transmission shaft is rotatably mounted in the shell, a transmission wheel is arranged at one end, extending out of the shell, of the transmission shaft, an anti-dazzling screen is arranged at one end in the shell, and the transmission wheel, the transmission shaft and the anti-dazzling screen are coaxially arranged; an optical fiber correlation assembly is arranged in the shell, and the anti-dazzling screen forms a light transmitting area and a light blocking area on an optical signal transmission path of the optical fiber correlation assembly; the lower portion of the shell is provided with a supporting structure enabling the transmission wheel to abut against the surface of the conveying belt, the speed of the conveying belt is converted into the pulse frequency of an optical signal, the pulse signal is output in the mode that an optical fiber serves as a medium to directly transmit the pulse signal, and the supporting structure can ensure that the speed of the conveying belt can be accurately transmitted to the sensor. The defects of electronic signal type speed sensors in engineering application are overcome, the stability is high, and the service life is long.

Description

Technical Field

[0001] The utility model belongs to the field of comprehensive protection of universal belt conveyors, and specifically relates to an optical fiber speed sensor. Background Art

[0002] At present, all protection switches (sensors) including speed sensors in the comprehensive protection system of belt conveyors mostly use power-on switches. For economy, the switch is transmitted to the upper control system through a certain communication system to realize the positioning of multiple switches. However, this solution requires the increase of control power supply, complex system composition, and the installation of electronic devices at the industrial site. The stability is easily affected by the temperature at the site. In addition, it is often affected by strong electromagnetic interference at the site, oxidation of communication cable connectors and other problems, resulting in a decrease in communication quality and even disconnection, which has a great impact on the failure downtime rate of long-distance belt conveyors. Utility Model Content

[0003] The technical problem to be solved by the utility model is to provide an optical fiber speed sensor, which overcomes the shortcomings of electronic signal speed sensors in engineering applications, has high stability and long service life, and is suitable for speed detection of long-distance belt conveyors.

[0004] In order to solve the above technical problems, the technical solution of the utility model is:

[0005] A fiber optic speed sensor comprises a shell, a transmission shaft is rotatably mounted in the shell, a transmission wheel is provided at one end of the transmission shaft extending out of the shell, a shading sheet is provided at one end located in the shell, the transmission wheel, the transmission shaft and the shading sheet are coaxially arranged; an optical fiber matching assembly is arranged in the shell, the shading sheet forms a light-transmitting area and a light-blocking area on the optical signal transmission path of the optical fiber matching assembly; a supporting structure is provided at the lower part of the shell for making the transmission wheel rest against the surface of the conveyor belt.

[0006] Furthermore, the supporting structure includes a mounting plate and a tension spring, one side edge of the mounting plate is rotatably mounted on the lower end surface of the shell, one end of the tension spring is mounted on the end surface of the mounting plate close to the transmission wheel, and the other end is mounted on the end of the shell away from the transmission wheel.

[0007] Furthermore, a connecting plate is vertically arranged on the end surface of the mounting plate close to the transmission wheel, and one end of the tension spring is mounted on the edge of the connecting plate.

[0008] Furthermore, two tension springs are provided, and the two tension springs are respectively installed on two sides of the shell.

[0009] Furthermore, the housing includes a mounting tube sleeved on the outside of the transmission shaft, and bearings are installed between both ends of the mounting tube and the transmission shaft.

[0010] Furthermore, the transmission wheel is a gear or a roller.

[0011] Furthermore, a groove is provided on the edge of the shading sheet to form the light-transmitting area, and a plurality of the grooves are provided, and the plurality of the grooves are evenly distributed on the edge of the shading sheet.

[0012] Furthermore, the optical fiber reflection assembly includes an optical fiber for inputting and outputting optical signals and a grating for reflecting optical signals, and the input and output ends of the optical fiber and the reflection end of the grating are arranged opposite to each other.

[0013] Furthermore, a support for fixing the optical fiber beam assembly is arranged in the housing, and two supporting platforms are arranged opposite to each other on the support, and the input and output ends of the optical fiber and the reflecting end of the grating are respectively mounted on the two supporting platforms.

[0014] Furthermore, one end of the shell away from the transmission wheel is an opening, and an end cover is installed at the opening.

[0015] After adopting the above technical solution, the beneficial effects of the utility model are:

[0016] The optical fiber speed sensor of the utility model comprises a shell, a transmission shaft is rotatably installed in the shell, a transmission wheel is arranged at one end of the transmission shaft extending out of the shell, a shading plate is arranged at one end located in the shell, and the transmission wheel, transmission shaft and shading plate are arranged coaxially; an optical fiber matching assembly is arranged in the shell, and the shading plate forms a light-transmitting area and a light-blocking area on the optical signal transmission path of the optical fiber matching assembly; a supporting structure is arranged at the lower part of the shell so that the transmission wheel abuts against the surface of the conveyor belt, the speed of the conveyor belt is converted into the pulse frequency of the optical signal, and the pulse signal is directly transmitted and outputted by using the optical fiber as the medium, and the supporting structure can ensure that the speed of the conveyor belt can be accurately transmitted to the sensor of the utility model, thereby overcoming the shortcomings of electronic signal speed sensors in engineering applications, and having high stability and long service life. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a schematic diagram of the internal structure of the optical fiber velocity sensor of the utility model;

[0018] Figure 2 This is a schematic diagram of the external structure of the optical fiber velocity sensor of the utility model;

[0019] Figure 3 It is a structural schematic diagram of the optical fiber speed sensor of the utility model without the shell;

[0020] In the figure, 10-housing, 11-mounting cylinder, 12-bearing, 13-optical fiber interface, 14-end cover, 20-transmission wheel, 21-transmission shaft, 22-shading sheet, 23-optical fiber, 24-grating 24, 25-support, 30-rotating shaft, 31-mounting plate, 32-connecting plate, 33-tensioning spring. DETAILED DESCRIPTION

[0021] The present invention is further described below in conjunction with the accompanying drawings and embodiments. The preferred embodiments of the present invention are shown in the accompanying drawings. The purpose of the accompanying drawings is to supplement the description of the text part of the specification with graphics, so that people can intuitively and vividly understand each technical feature and the overall technical solution of the present invention, but it cannot be understood as a limitation on the protection scope of the present invention.

[0022] like Figure 1 and Figure 2 As shown together, an optical fiber speed sensor includes a housing 10, a transmission shaft 21 is rotatably mounted in the housing 10, a transmission wheel 20 is arranged at one end of the transmission shaft 21 extending out of the housing 10, and a light shielding sheet 22 is arranged at one end located in the housing 10, and the transmission wheel 20, the transmission shaft 21 and the light shielding sheet 22 are arranged coaxially. The transmission wheel 20 contacts the surface of the conveyor belt, and is used to convert the linear speed of the conveyor belt into a rotation speed signal, and transmit it to the light shielding sheet 22 through the transmission shaft 21. Among them, the transmission wheel 20 is a gear or a roller.

[0023] An optical fiber reflection assembly is arranged in the housing 10, and the optical fiber reflection assembly includes an optical fiber 23 for inputting and outputting optical signals and a grating 24 for reflecting optical signals. The input and output ends of the optical fiber 23 and the reflection end of the grating 24 are arranged relatively to each other. When there is no obstruction between the optical fiber 23 and the grating 24, the optical signal is output by the optical fiber 23 and reflected back to the optical fiber 23 through the grating 24. When there is an obstruction between the optical fiber 23 and the grating 24, the optical signal output by the optical fiber 23 cannot be reflected back to the optical fiber 23.

[0024] like Figure 3 As shown, the shading sheet 22 forms a light-transmitting area and a light-blocking area on the optical signal transmission path of the optical fiber reflection assembly. The shading sheet 22 is driven by the transmission shaft 21 to rotate to transmit the rotation speed signal. The light-transmitting area and the light-blocking area alternately pass between the optical fiber 23 and the grating 24. The grating 24 receives the returned light signal at intervals, thereby converting the linear speed signal of the conveyor belt into an optical pulse signal.

[0025] Specifically, a groove is provided at the edge of the light shielding sheet 22 to form a light-transmitting area, and a plurality of grooves are provided, and the plurality of grooves are evenly distributed on the edge of the light shielding sheet 22. In the present application, two grooves, i.e., light-transmitting areas, are provided on the light shielding sheet 22. The light-transmitting area is provided at the edge of the light shielding sheet 22, which is convenient for processing and can reduce the area of ​​the light shielding sheet 22 as much as possible, which is conducive to the miniaturization of the sensor.

[0026] like Figure 1 , Figure 2 and Figure 3 As shown together, a support structure for making the transmission wheel 20 abut against the surface of the conveyor belt is provided at the lower part of the housing 10. Specifically, the support structure includes a mounting plate 31 and a tension spring 33. One side edge of the mounting plate 31 is rotatably mounted on the lower end surface of the housing 10 through a rotating shaft 30. The mounting plate 31 is provided with a mounting hole for fixing bolts for mounting and fixing the sensor.

[0027] One end of the tension spring 33 is mounted on the end surface of the mounting plate 31 close to the transmission wheel 20, and the other end is mounted on the end of the housing 10 away from the transmission wheel 20. The end surface of the mounting plate 31 close to the transmission wheel 20 is vertically provided with a connecting plate 32, and one end of the tension spring 33 is mounted on the edge of the connecting plate 32. The sensor of the present application is installed under the conveyor belt. If the conveyor belt is in a horizontal state, the mounting plate 31 is vertically arranged and fixed by bolts. The housing 10 is subjected to the tension of the tension spring to apply an upward force to the transmission wheel 20, so that the transmission wheel 20 can be against the lower surface of the conveyor belt, ensuring that the transmission wheel 20 is always in good contact with the conveyor belt. There are two tension springs 33, and the two tension springs 33 are respectively installed on both sides of the housing 10.

[0028] like Figure 1 and Figure 2 As shown together, the housing 10 includes a mounting tube 11 sleeved on the outside of the transmission shaft 21, and bearings 12 are installed between the two ends of the mounting tube 11 and the transmission shaft 21. This structure has a good supporting effect on the transmission shaft 21. The upper end of the mounting plate 31 is rotatably connected to the lower part of the mounting tube 11. The end of the housing 10 away from the transmission wheel 20 is an opening, and an end cover 14 is installed at the opening. The end cover 14 plays a protective and sealing role, and the upper end of the pull-in spring is connected to the matching surface of the housing 10 and the end cover 14.

[0029] like Figure 1 and Figure 3 As shown together, a support 25 for fixing the optical fiber beam assembly is disposed in the housing 10, and two supporting platforms are disposed opposite to each other on the support 25, and the input and output ends of the optical fiber 23 and the reflection end of the grating 24 are respectively mounted on the two supporting platforms.

[0030] The bottom of the housing 10 is provided with an optical fiber interface 13, and the optical fiber 23 in the housing 10 is connected to the optical fiber interface 13. In actual use, after the optical modem is connected to the optical fiber interface 13, the optical fiber matching assembly starts to work. After being triggered, the reflection signal of the grating 24 makes the wavelength of the optical signal output by the optical fiber 23 through the optical fiber interface 13 correspond to the specific value of the grating. The optical modem will read and demodulate the optical signal of the wavelength of the specific value, and finally convert the linear speed of the conveyor belt according to the traditional ratio, pulse frequency, gear diameter and other information. In addition, different speed measurement positions use optical fiber matching assemblies with different wavelength specifications, and multiple optical fiber matching assemblies can be connected to the optical modem through a fiber core. The optical modem can locate the sensor with abnormal speed according to the demodulated signal.

[0031] The optical fiber speed sensor of the utility model converts the linear speed of the conveyor belt into the rotational speed of the shading sheet through the transmission shaft, shading sheet, optical fiber beam assembly arranged in the shell, and the transmission wheel and supporting structure outside the shell, and cooperates with the optical fiber beam assembly to convert it into an optical pulse signal, and uses optical fiber as the medium to directly transmit the pulse signal to achieve detection. There is no signal crosstalk and electromagnetic interference, no fear of lightning strikes, no leakage current, temperature and joint oxygen causing failures and communication quality problems, and it has extremely high lifespan and stability, reliability, and weather resistance. No power supply is required on site, and there is no problem of power supply over ultra-long distances.

[0032] In the description of this specification, it should be understood that the description involving orientation, such as the orientation or position relationship indicated as up or down, is based on the orientation or position relationship shown in the drawings, which is only for the convenience of describing the present invention and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0033] In the description of this specification, unless otherwise clearly defined, words such as "setting", "installation", and "connection" should be understood in a broad sense, and technicians in the relevant technical field can reasonably determine the specific meaning of the above words in this utility model based on the specific content of the technical solution.

[0034] Although the specific implementation methods of the utility model are described above, those skilled in the art should understand that the described embodiments are only part of the implementation methods of the utility model, rather than all the implementation methods, which are only examples, and the protection scope of the utility model is defined by the claims. Those skilled in the art can make various changes or modifications to these implementation methods without departing from the principle and essence of the utility model and without any creative work, but these changes and modifications fall within the protection scope of the utility model.

Claims

1. An optical fiber speed sensor, characterized in that: It comprises a housing, a transmission shaft is rotatably mounted in the housing, a transmission wheel is arranged at one end of the transmission shaft extending out of the housing, a light shielding sheet is arranged at one end of the transmission shaft located in the housing, and the transmission wheel, the transmission shaft and the light shielding sheet are coaxially arranged; An optical fiber beam assembly is arranged in the housing, and the light shielding sheet forms a light-transmitting area and a light-blocking area on the optical signal transmission path of the optical fiber beam assembly; The lower part of the shell is provided with a supporting structure for making the transmission wheel abut against the surface of the conveyor belt.

2. The optical fiber speed sensor according to claim 1, characterized in that: The supporting structure includes a mounting plate and a tension spring. One side edge of the mounting plate is rotatably mounted on the lower end surface of the shell. One end of the tension spring is mounted on the end surface of the mounting plate close to the transmission wheel, and the other end is mounted on the end of the shell away from the transmission wheel.

3. The optical fiber speed sensor according to claim 2, characterized in that: A connecting plate is vertically arranged on the end surface of the mounting plate close to the transmission wheel, and one end of the tension spring is mounted on the edge of the connecting plate.

4. The optical fiber speed sensor according to claim 3, characterized in that: Two tension springs are provided, and the two tension springs are respectively installed on two sides of the shell.

5. The optical fiber speed sensor according to claim 4, characterized in that: The housing comprises a mounting cylinder sleeved on the outer side of the transmission shaft, and bearings are mounted between the two ends of the mounting cylinder and the transmission shaft.

6. The optical fiber speed sensor according to claim 1, characterized in that: The transmission wheel is a gear or a roller.

7. The optical fiber speed sensor according to claim 1, characterized in that: A groove is formed at the edge of the light shielding sheet to form the light-transmitting area. There are a plurality of grooves, and the plurality of grooves are evenly distributed at the edge of the light shielding sheet.

8. The optical fiber speed sensor according to claim 7, characterized in that: The optical fiber matching assembly comprises an optical fiber for inputting and outputting optical signals and a grating for reflecting optical signals. The input and output ends of the optical fiber and the reflection end of the grating are arranged opposite to each other.

9. The optical fiber speed sensor according to claim 8, characterized in that: A support for fixing the optical fiber beam assembly is arranged in the housing, and two supporting platforms are arranged opposite to each other on the support, and the input and output ends of the optical fiber and the reflecting end of the grating are respectively mounted on the two supporting platforms.

10. The optical fiber speed sensor according to any one of claims 1 to 9, characterized in that: One end of the housing away from the transmission wheel is an opening, and an end cover is installed at the opening.

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