A multi-turn angular encoder based on a cycloidal speed reducer

Abstract

The present application belongs to the field of angle encoder, and particularly relates to a multi-turn angle encoder based on a cycloidal speed reducer, comprising a shell, a rotating shaft, a cycloidal speed reducer, and a single-turn detection part and a multi-turn detection part, wherein the shell comprises a lower shell and an upper shell, the single-turn detection part comprises a first transmitting part and a first receiving part, the first transmitting part is fixedly installed on the rotating shaft and rotates synchronously with the rotating shaft, and the first receiving part is installed on the lower shell; the eccentric shaft is provided with an upper circular port and a lower circular port, the eccentric shaft is fixedly sleeved on the outer wall of the rotating shaft, the outer cycloidal gear is installed on the lower circular port of the eccentric shaft through a second bearing, and the inner cycloidal gear is installed on the lower shell; the multi-turn detection part comprises a second transmitting part and a second receiving part, the second transmitting part is installed on the upper circular port of the eccentric shaft through a second bearing and is connected with the outer cycloidal gear through a pin and rotates synchronously with the outer cycloidal gear, and the second receiving part is installed on the lower shell. The present application solves the problems of limited speed reduction ratio and volume in the prior art.

Description

Technical Field

[0001] This invention belongs to the field of angle encoders, and specifically relates to a multi-turn angle encoder based on a cycloidal pinwheel reducer. Background Technology

[0002] An angle encoder is a device that converts the motion state of a rotating object into an electrical signal. Multi-turn angle encoders differ from single-turn angle encoders in that they have a wider measurement range and can measure angles greater than one turn (360°), making them an important component of modern automatic control systems.

[0003] The detection section of a multi-turn angle encoder generally consists of a single-turn detection section and a multi-turn detection section. The single-turn detection section is responsible for calculating the angle X, and the multi-turn detection section is responsible for calculating the number of turns Y, thus obtaining the current angle = X + Y * 360°.

[0004] Currently, the multi-turn detection section of multi-turn angle encoders uses a reducer to achieve its function, and similar products on the market all use planetary reducers or harmonic reducers.

[0005] A planetary reducer consists of a sun gear and multiple planetary gears. Based on gear speed conversion, when the input shaft drives the sun gear to rotate, the sun gear drives the planetary gears to rotate on their own axis and revolve around the ring gear, while simultaneously driving the output shaft to rotate, thereby achieving speed reduction. In practical applications, especially when manufacturing planetary reducers with speed ratios of 10 or higher, it is necessary to enlarge the diameter or add multiple reduction stages, resulting in an excessively large size that cannot be applied to encoders with reduction ratios greater than 10 and smaller size requirements.

[0006] Harmonic reducers consist of a flex wheel, a rigid wheel, and a wave generator. When the input shaft drives the wave generator to rotate, the external teeth of the flex wheel in the long axis direction fully mesh with the internal teeth of the rigid wheel, while they completely disengage in the short axis direction. The continuous rotation of the flex wheel forces it to alternately mesh and disengage with the teeth of the rigid wheel, thereby driving the output shaft to rotate and thus achieving speed reduction. In practical applications, most harmonic reducers have a speed ratio of 20 or higher and a large diameter, making them unsuitable for encoders with a reduction ratio of less than 20 and small size requirements. Summary of the Invention

[0007] The purpose of this invention is to provide a multi-turn angle encoder based on a cycloidal pinwheel reducer that can combine small size with a reduction ratio of 10~20, which can effectively solve the problems in the background art.

[0008] To achieve the above objectives, the technical solution adopted by the present invention is as follows: a multi-turn angle encoder based on a cycloidal pinwheel reducer, comprising a housing, a rotating shaft, and a cycloidal pinwheel reducer. The cycloidal pinwheel reducer includes an eccentric shaft, an outer cycloidal wheel, and an inner cycloidal wheel. The multi-turn angle encoder further includes a single-turn detection unit and a multi-turn detection unit. The housing includes a lower housing and an upper housing. The rotating shaft is rotatably mounted between the lower housing and the upper housing via a first bearing. The single-turn detection unit includes a first transmitting unit and a first receiving unit. The first transmitting unit is fixedly mounted on the rotating shaft and rotates synchronously with it. The first receiving unit is mounted on... On the lower housing; the eccentric shaft is provided with an upper circular opening and a lower circular opening. The eccentric shaft is fixedly sleeved on the outer wall of the rotating shaft. The upper circular opening is concentric with the rotating shaft, and the lower circular opening is eccentric to the rotating shaft. A second bearing is installed on both circular openings. The outer cycloidal wheel is installed on the lower circular opening of the eccentric shaft through the second bearing. The inner cycloidal wheel is installed on the lower housing. The outer cycloidal wheel and the inner cycloidal wheel are meshed and installed. The multi-turn detection unit includes a second transmitting unit and a second receiving unit. The second transmitting unit is installed on the upper circular opening of the eccentric shaft through the second bearing and is connected to the outer cycloidal wheel through a pin to rotate synchronously with it. The second receiving unit is installed on the lower housing.

[0009] A shoulder is provided on the outer wall of the rotating shaft. The first transmitting part is fixedly installed on the upper end face of the shoulder. The eccentric shaft is installed between the lower end face of the shoulder and the lower housing of the rotating shaft and is fixedly connected to the rotating shaft by a key. The single-turn detection part and the multi-turn detection part are connected by a pin header and nut header component. A microcontroller module is provided on the single-turn detection part. The microcontroller module is an ARM-based processor that calculates and converts the single-turn detection part and the multi-turn detection part into corresponding real-time absolute position information and sends it to the outside through the interface.

[0010] The first transmitting unit is equipped with a code disk made of permanent magnets, the first receiving unit is equipped with a microcontroller module, and the second transmitting unit is equipped with a code disk made of permanent magnets.

[0011] The first receiving unit is provided with N Hall sensors symmetrically distributed, where N is an even number; the second receiving unit is provided with M Hall sensors symmetrically distributed and connected to the first receiving unit through a pin header and nut header assembly, where M is an even number.

[0012] The microcontroller module analyzes the code disk information transmitted back by the Hall sensors on the first and second receiving units and sends it out through the interface.

[0013] The lower housing and the upper housing have concentric mounting holes at their centers, and a first bearing is installed in the mounting holes.

[0014] Compared with existing technologies, this invention has the following advantages: By using a cycloidal pinwheel reducer, it significantly reduces the size and weight of multi-turn encoders with the same number of detection turns, especially in the design of multi-turn encoders with a speed ratio of 10-20, thus expanding the application range of the multi-turn encoder. Although the cycloidal pinwheel reducer has high reduction ratio characteristics, it has not yet been effectively applied in the field of angle detection. The structural design is ingenious in its spatial layout, cleverly compressing the single-turn and multi-turn detection sections into a smaller space, rather than relying solely on simple linear transmission. Through the careful setting of the eccentric shaft 7, the transmission end can be folded back, resulting in a more compact structural layout. On this basis, the single-turn and multi-turn detection sections are then connected stably and efficiently through a pin header and nut header component, saving space while ensuring the accuracy and stability of signal transmission, demonstrating the ingenuity and practicality of the design.

[0015] The single external cycloidal wheel design offers advantages over traditional double external cycloidal wheel cycloidal pinwheel reducers in terms of simpler structure and easier maintenance. Furthermore, compared to planetary reducers and harmonic reducers, it significantly reduces the difficulty of design, installation, and maintenance. The integrated design of the cycloidal pinwheel reducer and encoder reduces axial space, making it suitable for confined installation environments. The cycloidal pinwheel reduction ratio enables mechanical multi-turn memory, eliminating the need for battery power and preventing data loss during power outages. The dual even-number symmetrical Hall array design, combined with an ARM processor filtering algorithm, suppresses electromagnetic noise and mechanical vibration interference. By adjusting the cycloidal pinwheel reduction ratio (e.g., from 1:50 to 1:100) and the number of Hall sensors, it can adapt to different resolution requirements. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the exploded structure of the present invention; Figure 2 This is a three-dimensional structural diagram of the present invention; Figure 3 This is a front view of the present invention; Figure 4 for Figure 3 Schematic diagram of the structure at point AA; Figure 5 This is a schematic diagram of the mounting structure of the first receiving unit of the present invention; Figure 6 This is a schematic diagram of the mounting structure of the first receiving unit and the second receiving unit of the present invention; Figure 7 This is a schematic diagram of the mounting structure of the first launching section of the present invention. Figure 8 This is a schematic diagram of the mounting structure of the outer and inner cycloidal wheels of the present invention. Figure 9 This is a schematic diagram of the three-dimensional structure of the eccentric shaft of the present invention; Figure 10 This is a front view of the eccentric axis of the present invention; Figure 11 This is a schematic diagram of the rotating shaft structure of the present invention.

[0017] In the figure: 1-lower housing; 2-upper housing; 3-rotating shaft; 31-shoulder; 4-first transmitting part; 5-first receiving part; 6-second receiving part; 7-eccentric shaft; 71-upper circular opening; 72-lower circular opening; 8-external cycloidal wheel; 9-inner cycloidal wheel; 10-second transmitting part; 101-pin; 11-first bearing; 12-second bearing; 13-pin and nut assembly. Detailed Implementation

[0018] To make the technical problems to be solved, the technical solutions, and the beneficial effects of this invention clearer, this invention will be further described in detail. It should be understood that the specific embodiments described herein are only for explaining this invention and are not intended to limit this invention.

[0019] like Figure 1-11 As shown, a multi-turn angle encoder based on a cycloidal pinwheel reducer includes a housing, a rotating shaft 3, and a cycloidal pinwheel reducer. The cycloidal pinwheel reducer includes an eccentric shaft 7, an outer cycloidal wheel 8, and an inner cycloidal wheel 9. The multi-turn angle encoder also includes a single-turn detection unit and a multi-turn detection unit. The housing includes a lower housing 1 and an upper housing 2. The lower housing 1 and the upper housing 2 have concentric mounting holes at their centers. A first bearing 11 is provided in each mounting hole on the lower housing 1 and the upper housing 2. The rotating shaft 3 is rotatably mounted between the lower housing 1 and the upper housing 2 via the first bearing 11. The rotating shaft 3 achieves bidirectional support and rotation via the first bearing 11, and the rotating shaft 3 constitutes the input shaft of the encoder. A shoulder 31 is provided on the outer wall of the rotating shaft 3. The single-turn detection unit includes a first transmitting part 4 and a first receiving part 5. The first transmitting part 4 is fixedly mounted on the upper end face of the shoulder 31 of the rotating shaft 3 and rotates synchronously with it. Figure 4-7 As shown, the eccentric shaft 7 is installed between the lower end face of the shoulder 31 of the rotating shaft 3 and the lower housing 1, and is fixedly connected to the rotating shaft 3 by a key. The first receiving part 5 is installed on the lower housing 1.

[0020] like Figure 4 , 9As shown in Figure 10, the eccentric shaft 7 has an upper circular opening 71 and a lower circular opening 72. The eccentric shaft 7 is fixedly sleeved on the outer wall of the rotating shaft 3. The upper circular opening 71 is concentric with the rotating shaft 3, and the lower circular opening 72 is eccentric to the rotating shaft 3. A second bearing 12 is installed on both circular openings. The outer cycloidal wheel 8 is installed on the lower circular opening 72 of the eccentric shaft 7 through the second bearing 12. The inner cycloidal wheel 9 is installed on the lower housing 1, and the outer cycloidal wheel 8 and the inner cycloidal wheel 9 are meshed together. The multi-turn detection unit includes a second transmitting unit 10 and a second receiving unit 6. The second transmitting unit 10 is installed on the upper circular opening 71 of the eccentric shaft 7 through the second bearing 12, and is connected to the outer cycloidal wheel 8 through a pin 101 to rotate synchronously with it. The second receiving unit 6 is installed on the lower housing 1. The above structural design and spatial layout compress the single-turn detection unit and the multi-turn detection unit into a smaller space, rather than relying solely on a simple linear transmission method. Through the careful setting of the eccentric shaft 7, the transmission end can be folded back, thus forming a more compact structural layout. Based on this, the single-turn detection unit and the multi-turn detection unit are connected in a stable and efficient manner through the pin header and nut header component 13, which saves space and ensures the accuracy and stability of signal transmission. The single-turn detection unit is equipped with a microcontroller module, which is an ARM-based processor. The microcontroller module calculates and converts the single-turn detection unit and the multi-turn detection unit into corresponding real-time absolute position information, and sends it to the outside through the interface.

[0021] The first transmitting unit 4 is equipped with a code disk made of permanent magnets, and the first receiving unit 5 is equipped with a microcontroller module. The first receiving unit 5 also has N symmetrically distributed Hall sensors, where N is an even number. The second transmitting unit 10 is equipped with a code disk made of permanent magnets, and the second receiving unit 6 has M symmetrically distributed Hall sensors, connected to the first receiving unit 5 via a pin header and nut header component 13, where M is an even number. The microcontroller module analyzes the code disk information returned by the Hall sensors on the first and second receiving units 5 and transmits it externally through an interface. The microcontroller module also analyzes the code disk information using the sinusoidal waveform returned by the Hall sensors on the first and second receiving units 5 and transmits it externally through an interface. The code disk of the single-turn detection unit is arranged with alternating N-pole and S-pole configurations, while the code disk of the multi-turn detection unit is designed according to the number of pole pairs corresponding to the reduction ratio, ensuring that the ARM processor can resolve the absolute position through phase difference.

[0022] When the input shaft rotates, it will drive the eccentric shaft 7 to rotate. The eccentric shaft 7 will drive the outer cycloidal wheel 8 to perform planetary motion in the inner cycloidal wheel 9. Since the teeth on the outer cycloidal wheel 8 mesh with the needle teeth on the inner cycloidal wheel 9, the outer cycloidal wheel 8 will drive the second launching part 10 connected to it to rotate when it rotates, and at the same time achieve deceleration.

[0023] The specific examples disclosed above are merely illustrative of the invention. These examples do not exhaustively describe all details, nor do they limit the invention to specific embodiments. Clearly, many modifications and variations can be made based on the content of this specification. The examples selected and specifically described in this specification are intended to better explain the principles and practical applications of the invention, thereby enabling those skilled in the art to better understand and utilize it.

Claims

1. A multi-turn angle encoder based on a cycloidal pinwheel reducer, comprising a housing, a rotating shaft (3), and a cycloidal pinwheel reducer, wherein the cycloidal pinwheel reducer comprises an eccentric shaft (7), an outer cycloidal wheel (8), and an inner cycloidal wheel (9), characterized in that: The multi-turn angle encoder further includes a single-turn detection unit and a multi-turn detection unit. The housing includes a lower housing (1) and an upper housing (2). The rotating shaft (3) is rotatably mounted between the lower housing (1) and the upper housing (2) via a first bearing (11). The single-turn detection unit includes a first transmitting unit (4) and a first receiving unit (5). The first transmitting unit (4) is fixedly mounted on the rotating shaft (3) and rotates synchronously with it. The first receiving unit (5) is mounted on the lower housing (1). The eccentric shaft (7) is provided with an upper circular opening (71) and a lower circular opening (72). The eccentric shaft (7) is fixedly sleeved on the outer wall of the rotating shaft (3). The upper circular opening (71) is concentric with the rotating shaft (3). The lower circular opening (72) is eccentric to the rotating shaft (3), and a second bearing (12) is installed on both circular openings. The outer cycloidal wheel (8) is installed on the lower circular opening (72) of the eccentric shaft (7) through the second bearing (12). The inner cycloidal wheel (9) is installed on the lower housing (1). The outer cycloidal wheel (8) and the inner cycloidal wheel (9) are meshed and installed. The multi-turn detection unit includes a second transmitting unit (10) and a second receiving unit (6). The second transmitting unit (10) is installed on the upper circular opening (71) of the eccentric shaft (7) through the second bearing (12), and is connected to the outer cycloidal wheel (8) through the pin (101) and rotates synchronously with it. The second receiving unit (6) is installed on the lower housing (1).

2. The multi-turn angle encoder based on a cycloidal pinwheel reducer according to claim 1, characterized in that: The outer wall of the rotating shaft (3) is provided with a shoulder (31). The first transmitting part (4) is fixedly installed on the upper end face of the shoulder (31). The eccentric shaft (7) is installed between the lower end face of the shoulder (31) of the rotating shaft (3) and the lower housing (1), and is fixedly connected to the rotating shaft (3) by a key. The single-turn detection part and the multi-turn detection part are connected by a pin header and nut header component (13). The single-turn detection part is provided with a microcontroller module. The microcontroller module is an ARM-based processor that calculates and converts the single-turn detection part and the multi-turn detection part into corresponding real-time absolute position information and sends it to the outside through the interface.

3. A multi-turn angle encoder based on a cycloidal pinwheel reducer according to claim 2, characterized in that: The first transmitting part (4) is provided with a code disk made of permanent magnets, the first receiving part (5) is provided with a microcontroller module, and the second transmitting part (10) is provided with a code disk made of permanent magnets.

4. A multi-turn angle encoder based on a cycloidal pinwheel reducer according to claim 3, characterized in that: The first receiving part (5) is provided with N Hall sensors that are symmetrically distributed, where N is an even number; the second receiving part (6) is provided with M Hall sensors that are symmetrically distributed, and is connected to the first receiving part (5) through a pin header and nut header component (13), where M is an even number.

5. A multi-turn angle encoder based on a cycloidal pinwheel reducer according to claim 4, characterized in that: The microcontroller module parses the code disk information transmitted back by the Hall sensors on the first receiving unit (5) and the second receiving unit (6), and sends it to the outside through the interface.

6. A multi-turn angle encoder based on a cycloidal pinwheel reducer according to any one of claims 1 to 5, characterized in that: The lower housing (1) and the upper housing (2) are provided with concentric mounting holes at their centers, and a first bearing (11) is provided in the mounting holes.

Images