Angle sensor based on double-carbon-film potentiometer
By designing a dual-carbon film potentiometer angle sensor, the problems of blind zone, high power consumption, and large temperature drift in existing technologies have been solved, achieving low-power, high-precision 360-degree blind-zone-free rotation measurement.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-01-05
- Publication Date
- 2026-04-03
AI Technical Summary
Existing single-turn angle sensors suffer from problems such as blind spots in angle measurement, high power consumption, large temperature drift, and high static operating current.
Adopting the principle of dual carbon film potentiometers, a dual-ring arrangement structure of inner and outer carbon film potentiometers is designed. The inner and outer ring brushes can rotate 360 degrees without dead angles. Combined with the operational amplifier to form an operational circuit, 360-degree rotation measurement without blind spots is achieved.
It achieves angle measurement with low energy consumption, high accuracy, and small temperature drift, meets the requirements of two-wire current, has a simple structure, and the sensor can achieve 360-degree rotation measurement without blind spots.
Smart Images
Figure CN121782987A_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of angle sensors, specifically to an angle sensor based on a dual carbon film potentiometer. Background Technology
[0002] Single-circle angle sensor positioning technology is mostly implemented using principles such as potentiometers, magnetic chips, optics, magnetic gratings, and inductors. Each of these has its own characteristics and application scenarios, specifically in fields such as industry, water conservancy, energy, and coal.
[0003] Existing technologies have drawbacks such as blind spots in angle measurement, high power consumption, large temperature drift, and high static operating current. Summary of the Invention
[0004] The purpose of this application is to provide an angle sensor based on a dual carbon film potentiometer. Compared with traditional potentiometers, the dual carbon film potentiometer principle eliminates the angle blind zone problem, and the sensor can be made to perform 360-degree blind zone-free rotation measurement.
[0005] To achieve the above objectives, this application provides the following technical solution:
[0006] This application provides an angle sensor based on a dual carbon film potentiometer, including a carbon film potentiometer. The carbon film potentiometer has a dual-ring arrangement structure with an inner ring carbon film potentiometer and an outer ring carbon film potentiometer. Both the inner and outer ring carbon film potentiometers have two fixed leads. Inner ring brushes and outer ring brushes are correspondingly arranged on the inner and outer ring carbon film potentiometers. The fixed leads of the inner and outer ring carbon film potentiometers and the leads of the inner and outer ring brushes are connected to a circuit board. The circuit board is mounted on a circuit board support. A support pad is provided below the circuit board support. A driving gear and a driven gear are provided below the support pad. The driving gear drives the driven gear to rotate, thereby causing the inner and outer ring brushes to rotate. The driving gear is installed inside the sensor housing. A mounting base is provided below the driving gear. A cover plate is provided above the inner and outer ring brushes to close the sensor housing.
[0007] The two fixed leads of the inner ring carbon film potentiometer are arranged vertically and vertically, 180° apart, while the two fixed leads of the outer ring carbon film potentiometer are arranged horizontally and vertically, 180° apart.
[0008] The inner and outer ring brushes rotate 360 degrees without any blind spots.
[0009] The circuit board has a computing circuit consisting of four operational amplifiers.
[0010] The drive gear is connected to the main shaft, and a snap ring is provided on the main shaft to connect the main shaft and the drive gear. The lower end of the main shaft is mounted on the mounting base through a bearing.
[0011] The sensor housing is fixedly mounted on the mounting base using flathead screws.
[0012] The driven gears include a first driven gear, a second driven gear, a third driven gear, a fourth driven gear, and a fifth driven gear. The first driven gear is installed via bearing screws and meshes with the driving gear. The second, third, and fourth driven gears are respectively mounted on the mounting base via driven gear shafts and driven gear bushings. The second driven gear meshes with the first driven gear, the third driven gear meshes with the second driven gear, the fourth driven gear meshes with the third driven gear, and the fifth driven gear meshes with the fourth driven gear. The shaft of the fifth driven gear is connected to the carbon film potentiometer via a bushing and a washer. The rotation of the fifth driven gear drives the inner ring brush and the outer ring brush to rotate.
[0013] The bracket pad is fixedly installed on the mounting base by pad fixing screws, and the pad fixing screws are also fitted with screw sleeves.
[0014] The inner ring brush is fixed by a short brush bracket, and the outer ring brush is fixed by a long brush bracket.
[0015] Compared with the prior art, the beneficial effects of the present invention are:
[0016] It has low energy consumption because it adopts the principle of two carbon film potentiometers. When the resistance of the two ends of the carbon film potentiometer is 10k ohms and the power supply is 5V, the current of the measurement part is 0.5mA*2 =1mA. With the addition of the operation circuit, the energy consumption of the whole machine is much less than 3mA, which meets the two-wire current requirement that the working part is less than 3.5mA.
[0017] It has high precision because it uses a carbon film potentiometer as the measurement standard, and the linearity of the resistance plate can reach 0.05%FS throughout the production process.
[0018] The sensor has low temperature drift because it uses a carbon film potentiometer, which can control the temperature drift to below ±20ppm during production.
[0019] With a simple structure, the angle measurement standard can be integrally formed because it uses a carbon film potentiometer.
[0020] Compared with traditional potentiometers, the dual carbon film potentiometer principle eliminates the angular blind zone problem, and the sensor can be made to perform 360-degree blind zone-free rotation measurement. Attached Figure Description
[0021] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments of this application will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.
[0022] Figure 1 This is a schematic diagram of the carbon film potentiometer structure according to an embodiment of this application;
[0023] Figure 2 This is a schematic diagram of the lead wires of the double carbon film structure according to an embodiment of this application;
[0024] Figure 3 This is a voltage output curve of the dual carbon film potentiometer according to an embodiment of this application;
[0025] Figure 4 This is a schematic diagram of the operational circuit of the sensor according to an embodiment of this application;
[0026] Figure 5 This is an exploded view of the overall structure of the sensor according to an embodiment of this application;
[0027] Figure 6 This is a top view schematic diagram of the sensor according to an embodiment of this application;
[0028] Figure 7 This is a schematic cross-sectional view of an embodiment of this application. Detailed Implementation
[0029] The technical solutions of the embodiments of this application will now be described with reference to the accompanying drawings. It should be noted that similar reference numerals and letters in the following drawings indicate similar items; therefore, once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings.
[0030] The terms “comprising,” “including,” or any other variations thereof are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase “comprising one…” does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.
[0031] like Figure 1 and Figure 5As shown, the purpose of this application is to provide an angle sensor based on a dual carbon film potentiometer, including a carbon film potentiometer. The carbon film potentiometer has a dual-ring arrangement structure of an inner ring carbon film potentiometer 1 and an outer ring carbon film potentiometer 2. Both the inner ring carbon film potentiometer 1 and the outer ring carbon film potentiometer 2 have two fixed leads. An inner ring brush 13 and an outer ring brush 23 are correspondingly arranged on the inner ring carbon film potentiometer 1 and the outer ring carbon film potentiometer 2. The fixed leads of the inner ring carbon film potentiometer 1 and the outer ring carbon film potentiometer 2, as well as the inner ring brush and the outer ring brush, are also provided. The lead-out end is connected to the circuit board 3. The circuit board 3 is mounted on the circuit board bracket 4. A bracket pad 5 is provided below the circuit board bracket 4. A drive gear 14 and a driven gear are provided below the bracket pad 5. The drive gear 14 drives the driven gear to rotate, thereby causing the inner ring brush and the outer ring brush to rotate. The drive gear 14 is installed inside the sensor housing 18. A mounting base 24 is provided below the drive gear 14. A cover plate 31 is provided above the inner ring brush 13 and the outer ring brush 23 to close the sensor housing 18.
[0032] like Figures 1-7 As shown, the two fixed leads of the inner ring carbon film potentiometer 1 are arranged vertically and vertically, 180° apart, while the two fixed leads of the outer ring carbon film potentiometer 2 are arranged horizontally and vertically, 180° apart.
[0033] The inner ring brush 13 and the outer ring brush 23 rotate 360 degrees without any dead angle.
[0034] The circuit board 3 has a computing circuit consisting of four operational amplifiers.
[0035] The drive gear 14 is connected to the main shaft 15. A snap ring 16 is provided on the main shaft 15 to connect the main shaft 15 and the drive gear 14. The lower end of the main shaft 15 is mounted on the mounting base 24 through a bearing 17.
[0036] The sensor housing 18 is fixedly mounted on the mounting base 24 by flathead screws 20.
[0037] The driven gears include a first driven gear 10, a second driven gear 9, a third driven gear 8, a fourth driven gear 7, and a fifth driven gear 6. The first driven gear 10 is installed via bearing screws 29 and meshes with the driving gear 14. The second driven gear 9, the third driven gear 8, and the fourth driven gear 7 are respectively installed on the mounting base 24 via driven gear shafts 28 and driven gear bushings 30. The second driven gear 9 meshes with the first driven gear 10, the third driven gear 8 meshes with the second driven gear 9, the fourth driven gear 7 meshes with the third driven gear 8, and the fifth driven gear 6 meshes with the fourth driven gear 7. The rotating shaft of the fifth driven gear 6 is connected to the carbon film potentiometer via bushing 26 and washer 27. The rotation of the fifth driven gear 6 drives the inner ring brush 13 and the outer ring brush 23 to rotate.
[0038] The bracket pad 5 is fixedly installed on the mounting base 24 by the pad fixing screw 25, and the pad fixing screw 25 is also fitted with a screw sleeve 19.
[0039] The inner ring brush 13 is fixed by a short brush bracket 33, and the outer ring brush 23 is fixed by a long brush bracket 32.
[0040] The following example demonstrates the angle calculation process:
[0041] Set the inner and outer carbon film potentiometers to 10K ohms. Connect the upper connection point 11 of the inner ring carbon film to 0V, the lower connection point 12 of the inner ring carbon film to 5V, the left connection point 21 of the outer ring carbon film to 0V, and the right connection point 22 of the outer ring carbon film to 5V.
[0042] When the inner and outer carbon film potentiometers are at 0 degrees of rotation, the inner ring brush 13 and outer ring brush 23 can achieve 0V inner voltage and 2.5V outer voltage according to the principle of voltage division. When the rotation point is at 90 degrees of rotation, 2.5V inner voltage and 0V outer voltage can be achieved. Rotating 360 degrees sequentially yields the following results: Figure 3 .
[0043] according to Figure 3 It can be seen that the output voltage of the inner resistance ring is divided into two regions: it rises when rotating from 0 to 180 degrees and falls when rotating from 180 to 0 degrees. The output voltage of the outer resistance ring falls when rotating from 0 to 90 degrees, rises when rotating from 90 to 270 degrees, and falls when rotating from 270 to 0 degrees.
[0044] Based on the above characteristics, it can be concluded that when the inner resistance ring of the inner ring carbon film potentiometer outputs 0-5V from 0 to 180 degrees, the outer resistance ring outputs less than or equal to 2.5V; when the inner resistance ring outputs 5-0V from 180 to 0 degrees, the outer resistance ring outputs greater than or equal to 2.5V.
[0045] Based on this characteristic, the arithmetic circuit design is as follows: Figure 4 Considering that the sensor requires a 0-10V output power supply of 12V, the internal LDO circuit converts 12V to 5V. In the schematic diagram of the operational circuit, R9 is the inner ring carbon film potentiometer, R10 is the outer ring carbon film potentiometer, S1 is the double-pole double-throw electronic switch, and U1 is the quad operational amplifier integrated circuit.
[0046] There are two types of work status:
[0047] When the voltage of the first type of outer ring carbon film potentiometer is less than 2.5V, U1D acts as a comparator. The voltage at the input terminal is 2.5V. After comparison, the output voltage is L. S1 is the initial state. The inner ring carbon film potentiometer is directly output from U1C in phase, resulting in 0-5V.
[0048] When the voltage of the second type of outer ring carbon film potentiometer is greater than 2.5V, U1D acts as a comparator. The voltage at the input terminal is 2.5V. After comparison, the output voltage is H. S1 is in working state. The voltage of the inner ring carbon film potentiometer is output as 5V-10V by the U1A subtractor and the U1B adder.
[0049] The sensor output changes from 0 to 360 degrees through the calculation circuit to a change of 0 to 10V, which is then converted to output by the U1C in-phase impedance transformer. Based on this circuit, two-wire and three-wire current loop circuits can be added to realize current output applications.
[0050] The above description is merely an embodiment of this application and is not intended to limit the scope of protection of this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of protection of this application.
Claims
1. An angle sensor based on a dual carbon film potentiometer, characterized in that, The sensor includes a carbon film potentiometer, which has a double-ring arrangement of an inner ring carbon film potentiometer and an outer ring carbon film potentiometer. Both the inner and outer ring carbon film potentiometers have two fixed leads. Inner ring brushes and outer ring brushes are correspondingly arranged on the inner and outer ring carbon film potentiometers. The fixed leads of the inner and outer ring carbon film potentiometers and the leads of the inner and outer ring brushes are connected to a circuit board. The circuit board is mounted on a circuit board support. A support pad is set below the circuit board support. A driving gear and a driven gear are set below the support pad. The driving gear drives the driven gear to rotate, thereby causing the inner and outer ring brushes to rotate. The driving gear is installed inside the sensor housing. A mounting base is set below the driving gear. A cover plate is set above the inner and outer ring brushes to close the sensor housing.
2. The angle sensor based on a dual carbon film potentiometer according to claim 1, characterized in that, The two fixed leads of the inner ring carbon film potentiometer are arranged vertically and vertically, 180° apart, while the two fixed leads of the outer ring carbon film potentiometer are arranged horizontally and vertically, 180° apart.
3. The angle sensor based on a dual carbon film potentiometer according to claim 1, characterized in that, The inner and outer ring brushes rotate 360 degrees without any blind spots.
4. The angle sensor based on a dual carbon film potentiometer according to claim 1, characterized in that, The circuit board has a computing circuit consisting of four operational amplifiers.
5. The angle sensor based on a dual carbon film potentiometer according to claim 1, characterized in that, The drive gear is connected to the main shaft, and a snap ring is provided on the main shaft to connect the main shaft and the drive gear. The lower end of the main shaft is mounted on the mounting base through a bearing.
6. The angle sensor based on a dual carbon film potentiometer according to claim 1, characterized in that, The sensor housing is fixedly mounted on the mounting base using flathead screws.
7. The angle sensor based on a dual carbon film potentiometer according to claim 1, characterized in that, The driven gears include a first driven gear, a second driven gear, a third driven gear, a fourth driven gear, and a fifth driven gear. The first driven gear is installed via bearing screws and meshes with the driving gear. The second, third, and fourth driven gears are respectively mounted on the mounting base via driven gear shafts and driven gear bushings. The second driven gear meshes with the first driven gear, the third driven gear meshes with the second driven gear, the fourth driven gear meshes with the third driven gear, and the fifth driven gear meshes with the fourth driven gear. The shaft of the fifth driven gear is connected to the carbon film potentiometer via a bushing and a washer. The rotation of the fifth driven gear drives the inner ring brush and the outer ring brush to rotate.
8. The angle sensor based on a dual carbon film potentiometer according to claim 1, characterized in that, The bracket pad is fixedly installed on the mounting base by pad fixing screws, and the pad fixing screws are also fitted with screw sleeves.
9. The angle sensor based on a dual carbon film potentiometer according to claim 1, characterized in that, The inner ring brush is fixed by a short brush bracket, and the outer ring brush is fixed by a long brush bracket.