Dual read head distributed true multi-turn absolute value encoder structure

Abstract

The application discloses a double-reading-head distributed true multi-turn absolute value encoder structure which comprises a shell, a front end cover detachably arranged at one end of the shell, a rear end cover detachably arranged at the other end of the shell, a control panel arranged in the rear end cover, a rotating seat fixedly arranged on the front end cover, a hollow shaft fixedly arranged on the rotating seat in the shell, a light source emitter and a photoelectric sensor arranged in the shell on one side of the hollow shaft, a grating disc fixedly sleeved on the hollow shaft and inserted between the photoelectric sensor and the light source emitter, a threaded groove arranged on the inner wall of the hollow shaft, a telescopic column inserted into the free end of the hollow shaft and connected with the hollow shaft through the threaded groove, and a distance sensor and a spring arranged in the shell, wherein the distance sensor, the light source emitter and the photoelectric sensor are electrically connected with the control panel, and the input end of the distance sensor is opposite to the end of the telescopic column. The whole structure is reasonable, linkage is strong, detection precision is high, stability is good and maintenance is convenient.

Description

Technical Field

[0001] This application belongs to the field of multi-turn absolute encoders, and in particular relates to a structure of a dual-readhead distributed true multi-turn absolute encoder. Background Technology

[0002] In fields such as industrial automation, precision mechanical transmission, and intelligent control, absolute encoders, as core components capable of accurately detecting rotation angles and rotation counts, are widely used in various devices requiring positioning, speed measurement, and counting. Among them, true multi-turn absolute encoders, compared to single-turn encoders, do not rely on an external power supply to memorize rotation counts and can directly output absolute position information. They also retain data even after power failure, greatly improving the reliability and convenience of equipment operation, and have become the mainstream choice in high-end equipment.

[0003] Currently, true multi-turn absolute encoders on the market are mainly divided into two categories: mechanical gear type and electronic type. Mechanical gear type true multi-turn encoders achieve multi-turn counting through the meshing of multiple sets of gears, but their structure is complex and has many parts. After long-term use, problems such as gear wear and jamming are prone to occur, which not only affects the detection accuracy but also shortens the encoder's lifespan and has high maintenance costs. Although electronic true multi-turn encoders avoid the problem of mechanical wear, most of them use a single reading head design. The detection accuracy is greatly affected by environmental vibration and temperature changes, and signal loss and counting errors are prone to occur during multi-turn counting, making it difficult to meet the stringent requirements of high-end precision equipment for encoding accuracy and stability.

[0004] In addition, the power transmission structure of existing encoders is mostly a rigid connection, and the vibration of the external transmission mechanism can be directly transmitted to the internal precision detection components, causing the grating disk, sensor and other components to shift, further reducing the detection accuracy. At the same time, the cooperation stability between the telescopic column and the hollow shaft is insufficient, and it is easy to have free rotation and slippage, which affects the accuracy of multi-turn counting. The design of the outlet sealing and the wiring fixing structure is unreasonable, which can easily lead to the entry of impurities or loosening of the wiring, affecting the long-term stable operation of the encoder.

[0005] Therefore, we need to design a dual-readhead distributed true multi-turn absolute encoder structure to solve these problems. Summary of the Invention

[0006] The problem this application aims to solve is to provide a true multi-turn absolute encoder with a reasonable structure, strong linkage, high detection accuracy, good stability, and convenient maintenance.

[0007] To achieve the above objectives, the technical solution adopted in this application is as follows:

[0008] A dual-readhead distributed true multi-turn absolute encoder structure includes a housing. A front cover is detachably mounted on one end of the housing, and a rear cover is detachably mounted on the other end. A control board is housed inside the rear cover. A rotating seat is fixedly mounted on the front cover. A hollow shaft is fixedly mounted on the rotating seat located inside the housing. A light source emitter and a photoelectric sensor are housed inside the housing on one side of the hollow shaft. A grating disk is fixedly fitted onto the hollow shaft, and the grating disk is inserted between the photoelectric sensor and the light source emitter. A threaded groove is provided on the inner wall of the hollow shaft. A telescopic column is inserted into the free end of the hollow shaft. The telescopic column is connected to the hollow shaft through a threaded groove. A distance sensor and a spring are also provided inside the housing. The distance sensor, the light source emitter, and the photoelectric sensor are all electrically connected to the control board. The input end of the distance sensor is opposite to the end of the telescopic column. The spring is located between the distance sensor and the telescopic column and applies a thrust to the telescopic column towards the hollow shaft. When the hollow shaft rotates, the end of the telescopic column will move closer to or away from the input end of the distance sensor.

[0009] Preferably, an installation plate is also fixedly installed inside the housing, and a guide tube is fixedly installed on the installation plate. The free end of the telescopic column is inserted from the free end of the guide tube. The distance sensor is fixed on the installation plate, and its output end is opposite to the end of the telescopic column inside the guide tube. The spring is located inside the guide tube, with one end fixedly connected to the installation plate and the other end fixedly connected to the telescopic column.

[0010] This design provides precise guidance and limitation for the movement of the telescopic column, further improving detection accuracy and structural stability. The mounting plate provides a stable mounting platform for the guide tube and distance sensor, ensuring the accuracy of their installation positions and preventing distance detection deviations caused by component misalignment. The guide tube strictly limits the movement trajectory of the telescopic column, preventing tilting or offset during axial movement and ensuring that the end of the telescopic column is always aligned with the input end of the distance sensor, thus guaranteeing the accuracy of distance detection. The spring is located inside the guide tube, which not only prevents interference from other components within the housing but also ensures that the spring force always acts along the axis of the telescopic column, guaranteeing a tight fit between the telescopic column and the hollow shaft thread groove. At the same time, the guide tube protects the spring, preventing deformation or misalignment due to long-term telescopic movement, extending the spring's service life, and thus ensuring the long-term stable operation of the encoder.

[0011] Preferably, a limiting block is fixedly provided at the free end of the guide tube, and a plurality of guide grooves are provided on the outer wall of the telescopic column along its axial direction, and the limiting ring slides in cooperation with the guide grooves.

[0012] This design further optimizes the guiding effect of the telescopic column and simultaneously limits its movement, preventing component damage. The sliding fit between the limiting block and the guide groove on the outer wall of the telescopic column further restricts its rotation, ensuring that the column can only move axially. This prevents threaded fit failure and increased detection errors caused by the telescopic column rotating synchronously with the hollow shaft. The cooperation between the guide groove and the limiting block also limits the travel of the telescopic column, preventing excessive movement beyond the guide tube's range or collision with the distance sensor that could damage the component. Furthermore, the sliding fit structure has low frictional resistance, ensuring smooth movement of the telescopic column and guaranteeing the continuity and accuracy of the coding count.

[0013] Preferably, a push block is fixedly provided at the end of the telescopic column inside the hollow shaft, and the push block cooperates with the threaded groove through ball bearings.

[0014] This design reduces the frictional resistance between the telescopic column and the hollow shaft, improving component lifespan and smoothness of movement. The push block increases the contact stability between the telescopic column and the hollow shaft's threaded groove, preventing the end of the telescopic column from directly contacting the threaded groove and causing excessive wear. The interaction between the ball bearings and the threaded groove converts sliding friction into rolling friction, significantly reducing the frictional resistance between them. This allows the telescopic column to move more smoothly along the axial direction when the hollow shaft rotates, reducing the occurrence of jamming and stuck phenomena. At the same time, it reduces component wear, extends the overall lifespan of the encoder, and ensures the stability and accuracy of encoding detection during long-term use.

[0015] Preferably, a push plate is also fixedly provided at the end of the telescopic column inside the guide tube, and the spring is connected to the telescopic column through the push plate.

[0016] This design ensures that the spring force is evenly distributed across the telescopic column, preventing component damage and testing deviations caused by uneven localized stress. The push plate increases the contact area between the spring and the telescopic column, allowing the spring's thrust to be evenly transmitted to the column. This prevents the column from tilting or deforming due to excessive localized spring stress, ensuring the column always moves smoothly along its axis. Simultaneously, the push plate positions the spring, preventing it from shifting or misaligning during extension and retraction, ensuring the spring force remains along the column's axis. This further guarantees a tight fit between the telescopic column and the hollow shaft's threaded groove, improving testing accuracy and structural stability.

[0017] Preferably, the grating disk has a plurality of light-transmitting grooves.

[0018] This configuration enhances the sensitivity and accuracy of photoelectric detection, providing reliable support for single-turn angle encoding. The light-transmitting slots give the grating disk an alternating structure of light transmission and shading. When the hollow shaft drives the grating disk to rotate, the light emitted by the light source emitter alternately illuminates the photoelectric sensor through the light-transmitting slots, causing the photoelectric sensor to generate alternating high and low level electrical signals. These signals can accurately identify the rotation angle of the grating disk, thereby obtaining the single-turn rotation information of the hollow shaft. The distribution of several light-transmitting slots improves the resolution of angle detection, making single-turn angle detection more accurate and providing a high-quality foundation signal for subsequent true multi-turn encoding integration, ensuring the detection accuracy of the entire encoder.

[0019] Preferably, a fixing seat is also fixedly provided inside the housing, and the mounting plate is fixedly connected to the housing through the fixing seat.

[0020] This design enhances the installation stability of the mounting plate, indirectly ensuring the working accuracy of the guiding and detection components. The mounting base increases the connection area between the mounting plate and the housing, making the mounting plate more securely fixed within the housing. This prevents the mounting plate from loosening or shifting due to vibration during encoder operation, thereby preventing the guide tube, distance sensor, and other components from shifting position, ensuring the guiding accuracy of the telescopic column movement and the accuracy of distance detection. At the same time, the mounting base acts as a buffer for the mounting plate, reducing the impact of external vibrations on the components on the mounting plate, reducing vibration-induced detection errors, and improving the encoder's adaptability and stability under complex operating conditions.

[0021] Preferably, an elastic joint is also fixedly provided on the rotating seat located outside the front end cover. The elastic joint is fixedly connected to the hollow shaft through the rotating seat, and a mounting bracket can also be detachably provided at the front end.

[0022] This design facilitates encoder installation and fixation while protecting internal components from external stress. The flexible joint provides cushioning and shock absorption, preventing vibrations and impacts from external transmission mechanisms from being transmitted through the rotating base to internal precision components such as the hollow shaft and grating disk, thus preventing component damage or decreased detection accuracy. The detachable mounting bracket provides a convenient fixing structure for the overall encoder installation, facilitating quick docking and installation with external equipment, reducing installation difficulty. The mounting bracket can also be flexibly adjusted according to the actual installation scenario, improving the encoder's installation adaptability. The flexible joint and hollow shaft are fixedly connected via the rotating base, ensuring stable power transmission and preventing slippage or offset during power transmission, thus ensuring continuous encoding detection.

[0023] Preferably, a plurality of cable outlets are fixedly provided on the side wall of the rear end cover, and a lock nut can be detachably provided at the free end of each cable outlet.

[0024] This design facilitates wiring layout and fixation, while also improving the encoder's sealing and safety. Multiple cable outlets allow for the categorized arrangement of different lines, preventing tangling and confusion, facilitating later wiring inspection and maintenance, and enabling the selection of appropriate outlets based on actual usage needs, thus enhancing the flexibility of wiring layout. The detachable locknut secures the cable at the outlet, preventing poor contact due to pulling or vibration, ensuring stable signal transmission. Simultaneously, the locknut seals the gap between the outlet and the cable, preventing dust, moisture, and other impurities from entering the housing and damaging precision components such as the control board and sensors, improving the encoder's sealing and lifespan, and ensuring stable operation even in harsh environments.

[0025] The advantages and positive effects of this application are:

[0026] The structure described in this application converts the rotational input into the rotation of the hollow shaft, and then uses a threaded groove to convert the rotational motion into the linear displacement of the telescopic column. Together with the absolute value detection code disk composed of the grating disk, the light source emitter, and the photoelectric sensor, it forms a multi-turn absolute encoder. The displacement of the telescopic column is detected by a distance sensor, which can record the number of encoder rotations and indirectly obtain the number of rotations of the hollow shaft. Combined with the single-turn signal of the photoelectric sensor, true multi-turn absolute encoding is achieved. No additional mechanical counting structure is required, simplifying the overall design. Moreover, the position of the telescopic column remains unchanged. After reconnection, the rotation number information is obtained from the housing at the location of the telescopic column, and there is no loss of information when power is off. The structure has high integration and occupies little space. The spring provides a stable reset thrust for the telescopic column, ensuring sensitive motion response and reliable return. At the same time, it can also eliminate gaps, improve the accuracy of the equipment, and the whole structure is easy to disassemble and assemble, facilitating assembly and later maintenance. Attached Figure Description

[0027] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0028] Figure 1 This is a schematic diagram of the overall structure of this application;

[0029] Figure 2 This is a schematic cross-sectional view of the internal structure of this application;

[0030] Figure 3 This is a schematic diagram of the structure of the grating disk, light source emitter, and photoelectric switch in this application.

[0031] Figure 4This is a schematic diagram of the light-transmitting groove distribution structure on the grating disk of this application.

[0032] The annotations in the attached figures are explained as follows:

[0033] 1. Mounting bracket; 2. Housing; 3. Front cover; 4. Rear cover; 5. Flexible joint; 6. Control board; 7. Lock nut; 8. Cable outlet; 9. Light source emitter; 10. Photoelectric sensor; 11. Grating disk; 12. Rotating seat; 13. Threaded groove; 14. Hollow shaft; 15. Mounting plate; 16. Push block; 17. Telescopic column; 18. Limit block; 19. Guide groove; 20. Distance sensor; 21. Guide tube; 22. Spring; 23. Push plate; 24. Light transmission groove; 25. Fixing seat. Detailed Implementation

[0034] In the description of this application, it should be understood that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating orientation or positional relationships based on the orientation or positional relationships shown in the accompanying drawings, are used only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on this application. Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature. In the description of this application, unless otherwise stated, "a plurality of" means two or more.

[0035] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection between two components. Those skilled in the art will understand the specific meaning of the above terms in this application based on the specific circumstances.

[0036] The following description, in conjunction with the accompanying drawings, further illustrates this application:

[0037] Example 1: As Figures 1-4As shown, a dual-readhead distributed true multi-turn absolute encoder structure includes a housing 2, which serves as the external support base for the entire encoder, providing installation space and protection for all internal components. A front cover 3 is detachably mounted on one end, and a rear cover 4 is detachably mounted on the other end. The front cover 3 and rear cover 4 together form a sealed protection for the internal components of the housing 2, preventing external dust, moisture, and other impurities from entering and affecting the operation of the components. The detachable design also facilitates future maintenance and replacement of the internal components. A control board 6 is housed inside the rear cover 4, which serves as the signal processing and control unit for the entire encoder. The core of the system is designed to receive, process, and output encoded results of various detection signals. Its features include: a rotating seat 12 fixedly mounted on the front cover 3, providing fixed support for the hollow shaft 14 and ensuring its coaxiality during rotation; the hollow shaft 14 is fixedly mounted on the rotating seat 12 inside the housing 2, allowing the rotating seat 12 to drive the hollow shaft 14 to rotate synchronously, thus transmitting external power to the internal detection components; a light source emitter 9 and a photoelectric sensor 10 are symmetrically arranged inside the housing 2 on one side of the hollow shaft 14 to form a detection optical path, providing a basis for single-turn angle detection; such as Figure 3 As shown, a grating disk 11 is fixedly mounted on the hollow shaft 14. The grating disk 11 rotates synchronously with the hollow shaft 14 and is inserted between the photoelectric sensor 10 and the light source emitter 9. When the grating disk 11 rotates, it can alternately block or open the light path between the two, causing the photoelectric sensor 10 to generate alternating high and low level electrical signals, thereby realizing the detection of a single rotation angle. A threaded groove 13 is provided on the inner wall of the hollow shaft 14. A telescopic column 17 is inserted into the free end of the hollow shaft 14. The telescopic column 17 is connected to the hollow shaft 14 through the threaded groove 13. When the hollow shaft 14 rotates, the helical transmission of the threaded groove 13 drives the telescopic column 17 to move axially, converting the rotational motion of the hollow shaft 14 into the axial linear motion of the telescopic column 17. A distance sensor 20 and a spring 22 are also provided inside the housing 2. The distance sensor 20, the light source emitter 9, and the photoelectric sensor 10 are all electrically connected to the control board 6. The signals detected by the three sensors are all transmitted to the control board 6 for integrated processing. The input end of the distance sensor 20 is opposite to the end of the telescopic column 17 and is used to detect the axial displacement of the telescopic column 17, thereby indirectly obtaining the number of rotations of the hollow shaft 14. The spring 22 is located between the distance sensor 20 and the telescopic column 17 and applies a thrust to the telescopic column 17 into the hollow shaft 14 to ensure that the telescopic column 17 and the threaded groove 13 of the hollow shaft 14 are always tightly fitted, avoiding detection errors caused by free rotation or slippage. When the hollow shaft 14 rotates, the threaded groove 13 and the thrust of the spring 22 interact, causing the end of the telescopic column 17 to move closer to or away from the input end of the distance sensor 20. The distance sensor 20 converts the displacement signal into an electrical signal and transmits it to the control board 6. The control board 6 combines the single-turn angle signal transmitted by the photoelectric sensor 10 to finally realize multi-turn absolute value encoding and complete the entire encoding detection process.

[0038] A mounting plate 15 is also fixedly installed inside the housing 2. The mounting plate 15 serves as a fixed carrier for the guide tube 21 and the distance sensor 20, providing a stable installation reference for both and ensuring the accuracy of their installation positions, thus avoiding the impact of installation misalignment on the detection effect. The guide tube 21 is fixedly installed on the mounting plate 15, and the guide tube 21 is aligned with the axis of the telescopic column 17, providing precise guidance for the axial movement of the telescopic column 17 and limiting its movement trajectory. The free end of the telescopic column 17 is inserted into the free end of the guide tube 21, allowing the telescopic column 17 to move smoothly along the axis of the guide tube 21, avoiding tilting or offset during movement. The distance sensor 20 is fixed on the mounting plate 15, and its output end is aligned with the guide tube 21. The ends of the telescopic columns 17 inside are opposite each other, ensuring that the distance sensor 20 can accurately capture the displacement changes of the telescopic columns 17 and improve the accuracy of displacement detection. The spring 22 is located inside the guide tube 21, which limits and protects the spring 22, preventing the spring 22 from being misaligned or deformed during the extension and retraction process, and also avoiding interference between the spring 22 and other components inside the housing 2. One end of the spring 22 is fixedly connected to the mounting plate 15, and the other end is fixedly connected to the telescopic column 17, so that the elastic force of the spring 22 can act stably and evenly on the telescopic column 17, continuously ensuring the fit stability between the telescopic column 17 and the threaded groove 13 of the hollow shaft 14, and ensuring that the telescopic column 17 can move axially synchronously when the hollow shaft 14 rotates, providing a reliable guarantee for distance detection.

[0039] A limiting block 18 is fixedly installed at the free end of the guide tube 21. The limiting block 18 is fixed as a whole with the guide tube 21. Several guide grooves 19 are opened on the outer wall of the telescopic column 17 along its axial direction. The guide grooves 19 are matched with the size of the limiting block 18, and the limiting block 18 and the guide grooves 19 are slidably engaged. After the limiting block 18 is embedded in the guide groove 19, it can effectively restrict the telescopic column 17 from rotating synchronously with the hollow shaft 14, ensuring that the telescopic column 17 can only move axially along the axis of the guide tube 21, avoiding failure of the threaded fit due to the rotation of the telescopic column 17, and thus preventing the increase of detection error. At the same time, the cooperation between the limiting block 18 and the guide groove 19 can also indirectly limit the movement of the telescopic column 17, preventing the telescopic column 17 from moving excessively beyond the range of the guide tube 21, or from colliding with the distance sensor 20 and causing damage to the components, further ensuring the safety and stability of the linkage of each component, and ensuring that the accuracy of distance detection is not affected.

[0040] A push block 16 is fixedly installed at the end of the telescopic column 17 inside the hollow shaft 14. The push block 16 is fixedly connected to the telescopic column 17 and can move synchronously with the telescopic column 17. The push block 16 increases the contact area between the telescopic column 17 and the threaded groove 13 of the hollow shaft 14, improving the stability of their cooperation. The push block 16 cooperates with the threaded groove 13 through ball bearings. The ball bearings are embedded between the push block 16 and the threaded groove 13, converting the sliding friction between the push block 16 and the threaded groove 13 into rolling friction, which greatly reduces the transmission friction resistance between the two. This structural design allows the telescopic column 17 to move smoothly and axially when the hollow shaft 14 rotates, avoiding jamming or stuck phenomena, ensuring the continuous and stable displacement change of the telescopic column 17, thereby ensuring the continuity and accuracy of the detection signal of the distance sensor 20, and providing reliable support for the accurate calculation of multi-turn encoding.

[0041] A push plate 23 is fixedly installed at the end of the telescopic column 17 inside the guide tube 21. The push plate 23 is fixedly connected to the telescopic column 17 and can move axially synchronously with the telescopic column 17. The push plate 23 increases the contact area between the spring 22 and the telescopic column 17. The spring 22 is connected to the telescopic column 17 through the push plate 23, so that the elastic force of the spring 22 can be evenly transmitted to the end of the telescopic column 17, avoiding the telescopic column 17 from tilting or deforming due to uneven local force, and ensuring that the telescopic column 17 always moves smoothly along the axis of the guide tube 21. At the same time, the push plate 23 can also play a positioning role for the spring 22, preventing the spring 22 from shifting or misaligning during the telescopic process, ensuring that the elastic force direction of the spring 22 is always consistent with the axis of the telescopic column 17, and continuously providing the telescopic column 17 with the thrust into the hollow shaft 14, ensuring the tight fit between the telescopic column 17 and the threaded groove 13 of the hollow shaft 14, and further improving the stability of the entire detection system.

[0042] like Figure 4 As shown, several light-transmitting slots 24 are formed on the grating disk 11. When the grating disk 11 rotates synchronously with the hollow shaft 14, the light-transmitting slots 24 will alternately align with the optical path between the light source emitter 9 and the photoelectric sensor 10, so that the light emitted by the light source emitter 9 alternately shines on the photoelectric sensor 10 through the light-transmitting slots 24, or is blocked by the light-shielding part of the grating disk 11. The photoelectric sensor 10 generates a corresponding electrical signal according to the change of light on and off. The frequency of the electrical signal corresponds to the rotation speed of the grating disk 11, and the number of pulses of the electrical signal corresponds to the rotation angle of the grating disk 11, thereby realizing the accurate detection of the single-turn rotation angle of the hollow shaft 14, providing basic single-turn angle data for the control board 6 to integrate multi-turn coded signals.

[0043] A fixing seat 25 is also fixedly installed inside the housing 2. The fixing seat 25 is firmly connected to the inner wall of the housing 2 to ensure the installation stability of the fixing seat 25. The mounting plate 15 is fixedly connected to the housing 2 through the fixing seat 25. The fixing seat 25 increases the connection area between the mounting plate 15 and the housing 2, and improves the fixing strength and stability of the mounting plate 15. This structural design can effectively prevent the mounting plate 15 from shifting due to the impact force generated by external vibration or internal component movement when the encoder is working. This ensures the installation accuracy of components such as the guide tube 21 and the distance sensor 20, ensures the coaxiality of the guide tube 21 and the telescopic column 17, ensures the accurate relative position of the distance sensor 20 and the end of the telescopic column 17, and ultimately ensures smooth linkage between the components, improving the working stability and detection accuracy of the entire encoder.

[0044] An elastic joint 5 is also fixedly installed on the rotating seat 12 located on the outside of the front cover 3. The elastic joint 5 is used to connect with the external transmission mechanism and receive the power transmitted by the external transmission mechanism. At the same time, the elastic joint 5 has a certain buffering and shock absorption function, which can absorb the vibration and impact transmitted by the external transmission mechanism and prevent the vibration from being transmitted to the hollow shaft 14, grating disk 11 and other internal precision components through the rotating seat 12, so as to prevent component damage or reduction of detection accuracy. The elastic joint 5 and the hollow shaft 14 are fixedly connected through the rotating seat 12 to form a complete power transmission link. The external transmission mechanism can drive the rotating seat 12 and the hollow shaft 14 to rotate synchronously through the elastic joint 5 to ensure the stability and continuity of power transmission. In addition, a mounting bracket 1 can be detachably installed at the front end. The mounting bracket 1 is used to fix the entire encoder to the external device to realize the overall installation and positioning of the encoder. The detachable design facilitates the installation, disassembly and maintenance of the encoder and improves the installation adaptability of the encoder.

[0045] Several cable outlets 8 are fixedly installed on the side wall of the rear cover 4. The cable outlets 8 are connected to the interior of the rear cover 4 and are used for the signal lines and power supply lines connected to the control board 6 to pass through, realizing the signal output and power supply between the encoder and external devices. The design of several cable outlets 8 can realize the classification and arrangement of different types of lines, avoiding the tangling and mess of lines. A lock nut 7 can also be detachably installed at the free end of each cable outlet 8. After the lock nut 7 is tightened, the line passing through can be firmly fixed, preventing poor contact caused by pulling and vibration, and ensuring the stability of signal transmission and power supply. At the same time, the lock nut 7 can also seal the gap between the cable outlet 8 and the line, preventing external dust, moisture and other impurities from entering the housing 2 through the cable outlet 8 and damaging the control board 6, sensors and other precision components, further improving the sealing performance and service life of the encoder, and ensuring that the encoder can work stably under complex working conditions.

[0046] The working process of this embodiment is as follows: First, the encoder is fixed to the external device by the mounting bracket 1. The external transmission mechanism is connected to the elastic joint 5 on the rotating seat 12 on the outside of the front cover 3. The elastic joint 5 receives external power and absorbs vibration and impact during the transmission process, preventing vibration from being transmitted to internal precision components. Subsequently, the external transmission mechanism drives the elastic joint 5 to rotate. The elastic joint 5 drives the hollow shaft 14 inside the housing 2 to rotate synchronously through the rotating seat 12, realizing the stable transmission of external power to the internal detection components. The mounting plate 15 and guide tube 21 fixed by the fixed seat 25 remain stationary, providing a stable reference for the detection process.

[0047] Secondly, the single-turn angle detection stage. When the hollow shaft 14 rotates, the grating disk 11 fixedly mounted on its surface rotates synchronously with the hollow shaft 14. The light-transmitting slots 24 distributed on the grating disk 11 alternately align with the optical path between the light source emitter 9 and the photoelectric sensor 10. The light source emitter 9 continuously emits light. When the light-transmitting slot 24 is aligned with the optical path, the light shines through the light-transmitting slot 24 onto the photoelectric sensor 10. When the light-blocking part of the grating disk 11 is aligned with the optical path, the light is blocked. The photoelectric sensor 10 generates an alternating high and low level electrical signal according to the change in the light's on / off state. The number of pulses of this electrical signal corresponds to the rotation angle of the grating disk 11, and the frequency corresponds to the rotation speed. The photoelectric sensor 10 transmits this single-turn angle detection signal to the control board 6 inside the rear cover 4 in real time, completing the acquisition of single-turn angle data.

[0048] Next, the multi-turn counting detection process. As the hollow shaft 14 rotates, the threaded groove 13 on its inner wall engages with the push block 16 at the end of the telescopic column 17 via ball bearings, converting the rotational motion of the hollow shaft 14 into the axial linear motion of the telescopic column 17. At this time, the guide tube 21 provides precise guidance for the telescopic column 17. The limiting block 18 at the free end of the guide tube 21 slides into the guide groove 19 on the outer wall of the telescopic column 17, restricting the telescopic column 17 from rotating synchronously with the hollow shaft 14, ensuring that the telescopic column 17 moves only along the axis of the guide tube 21. The spring 22 inside the guide tube 21 applies a pushing force to the telescopic column 17 towards the interior of the hollow shaft 14 via the push plate 23, ensuring that the ball bearings on the push block 16 are always tightly engaged with the threaded groove 13 of the hollow shaft 14, eliminating any clearance. When the telescopic column 17 moves axially, the distance between its end and the input end of the distance sensor 20 on the mounting plate 15 changes. The distance sensor 20 detects the displacement in real time and converts it into an electrical signal, which is then transmitted to the control board 6. The control board 6 calculates the number of rotations of the hollow shaft 14 based on the displacement and completes the acquisition of multi-rotation count data.

[0049] Finally, the signal processing and encoding output stage. The control board 6, as the core, coordinates the reception of the single-turn angle signal transmitted by the photoelectric sensor 10 and the multi-turn counting signal transmitted by the distance sensor 20. It integrates and processes these two types of signals, ultimately converting them into multi-turn absolute value encoded signals. The encoded signal is transmitted to external devices through the signal line exiting from the side wall outlet 8 of the rear cover 4. The power supply line supplies power to the internal components of the encoder through the outlet 8. The locking nut 7 at the outlet 8 secures the line and seals the gap, preventing the line from loosening or allowing impurities to enter. Throughout the entire operation, the housing 2, front cover 3, and rear cover 4 form a closed protective enclosure. The mounting base 25 ensures the installation stability of the mounting plate 15 and each detection component. All components work together to ensure that the encoder continuously and accurately outputs multi-turn absolute value codes, completing the entire encoding detection process.

[0050] The foregoing has provided a detailed description of one embodiment of this application, but the description is merely a preferred embodiment and should not be construed as limiting the scope of this application. All equivalent variations and improvements made within the scope of this application should still fall within the patent coverage of this application.

Claims

1. A dual-reading-head distributed true multi-turn absolute encoder structure, comprising a housing (2), wherein a front end cover (3) is detachably disposed at one end of the housing (2), and a rear end cover (4) is detachably disposed at the other end, wherein a control board (6) is disposed inside the rear end cover (4), characterized in that: A rotating seat (12) is fixedly mounted on the front end cover (3). A hollow shaft (14) is fixedly mounted on the rotating seat (12) located inside the housing (2). A light source emitter (9) and a photoelectric sensor (10) are arranged inside the housing (2) on one side of the hollow shaft (14). A grating disk (11) is fixedly mounted on the hollow shaft (14), and the grating disk (11) is inserted between the photoelectric sensor (10) and the light source emitter (9). A threaded groove (13) is provided on the inner wall of the hollow shaft (14). A telescopic column (17) is inserted into the free end of the hollow shaft (14). The telescopic column (17) and the hollow shaft (14) are connected by the threaded groove (13). The groove (13) is connected to the housing (2). A distance sensor (20) and a spring (22) are also provided inside the housing (2). The distance sensor (20), the light source emitter (9) and the photoelectric sensor (10) are all electrically connected to the control board (6). The input end of the distance sensor (20) is opposite to the end of the telescopic column (17). The spring (22) is located between the distance sensor (20) and the telescopic column (17) and applies a thrust to the telescopic column (17) into the hollow shaft (14). When the hollow shaft (14) rotates, the end of the telescopic column (17) will move closer to or away from the input end of the distance sensor (20).

2. The structure of a dual-readhead distributed true multi-turn absolute encoder according to claim 1, characterized in that: An installation plate (15) is fixedly installed inside the housing (2). A guide tube (21) is fixedly installed on the installation plate (15). The free end of the telescopic column (17) is inserted from the free end of the guide tube (21). The distance sensor (20) is fixed on the installation plate (15), and its output end is opposite to the end of the telescopic column (17) inside the guide tube (21). The spring (22) is located inside the guide tube (21), with one end fixedly connected to the installation plate (15) and the other end fixedly connected to the telescopic column (17).

3. The structure of a dual-readhead distributed true multi-turn absolute encoder according to claim 2, characterized in that: A limiting block (18) is fixedly provided at the free end of the guide tube (21), and a plurality of guide grooves (19) are provided on the outer wall of the telescopic column (17) along its axial direction, and the limiting ring slides in cooperation with the guide grooves (19).

4. The structure of a dual-readhead distributed true multi-turn absolute encoder according to claim 1, characterized in that: A push block (16) is fixedly provided at the end of the telescopic column (17) inside the hollow shaft (14), and the push block (16) cooperates with the threaded groove (13) through ball bearings.

5. The structure of a dual-readhead distributed true multi-turn absolute encoder according to claim 2, characterized in that: A push plate (23) is also fixedly installed at the end of the telescopic column (17) inside the guide tube (21), and the spring (22) is connected to the telescopic column (17) through the push plate (23).

6. The structure of a dual-readhead distributed true multi-turn absolute encoder according to claim 1, characterized in that: The grating disk (11) has several light-transmitting grooves (24).

7. The structure of a dual-readhead distributed true multi-turn absolute encoder according to claim 2, characterized in that: A fixing seat (25) is also fixedly installed inside the housing (2), and the mounting plate (15) is fixedly connected to the housing (2) through the fixing seat (25).

8. The structure of a dual-readhead distributed true multi-turn absolute encoder according to claim 1, characterized in that: An elastic joint (5) is also fixedly installed on the rotating seat (12) located outside the front end cover (3). The elastic joint (5) is fixedly connected to the hollow shaft (14) through the rotating seat (12), and a mounting bracket (1) can also be detachably installed at the front end.

9. The structure of a dual-readhead distributed true multi-turn absolute encoder according to claim 1, characterized in that: Several cable outlets (8) are also fixedly provided on the side wall of the rear cover (4), and a lock nut (7) can be detachably provided at the free end of each cable outlet (8).

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