TW202120951A - Multi-turn contactless position sensing system and method - Google Patents

Abstract

Systems and methods for high-resolution multi-turn non-contact rotary sensing are disclosed herein. A position sensing device may include a first rotary shaft coupled to a second rotary shaft such that a rotation of the first rotary shaft causes the second rotary shaft to rotate. First and second magnets may be coupled to the first and second rotary shafts, respectively. The first and second rotary shafts may move angularly relative to at least one magnetic sensor circuit that is not in contact with the first or second rotary shafts. The at least one magnetic sensor circuit may measure angular positions of the first and second magnets to determine the angular position and number of rotations by the first rotary shaft.

Description

Multi-rotation non-contact position sensing system and method

The present invention generally relates to a position sensor, and more specifically, to a system and method for non-contact rotation sensing with high resolution and multiple revolutions.

For example, position sensors are used in mechanical and electrical applications to provide absolute position or displacement measurement information of objects. The angle or rotation sensor measures the mechanical angular position of a rotating object (for example, by measuring the position of a shaft connected to the rotating object), which can be used to determine other useful information, such as the frequency and speed of the object . Multi-rotation rotary position sensors are used in a variety of applications, including automotive and electric motor applications, consumer electronics and home appliances, industrial applications, wind turbines, solar systems, test and measurement equipment, robotics systems, and medical equipment.

An example of a position sensor is a potentiometer that measures the voltage drop when the electrical contact slides along the resistance track, so that the position (linear or rotary) is proportional to the voltage output. Although potentiometers are generally low-cost, simple to produce, and light in weight; however, they are susceptible to high-vibration environments and the presence of foreign particles (for example, dust). The operation of an optical sensor (also called an encoder) is to use a light detector to measure the light beam passing through the grating to generate a position signal. The optical sensor can provide high-resolution position measurement; however, it is very susceptible to the influence of foreign particles, making the measurement fail if the lens or grating system becomes blurred.

The magnetic sensor uses the magnetic detector to measure the change in the magnetic field of the magnet when the magnet moves relative to the magnetic detector, so that the change in the magnetic field is proportional to their relative displacement. The magnetic sensor is a non-contact (non-contact) sensor because there is no contact between the detector and the rotor shaft. An example of a magnetic angle position sensor is a Hall Effect sensor, which generates a voltage proportional to the density of the magnetic field of the rotating magnet passing through it from a rod-shaped conductive material called a Hall element. U.S. Patent Publication No. US 2013/00 15844 A1 discloses an existing non-contact multi-rotation rotational position sensing device that uses a single shaft and a dual magnetic sensor assembly to generate two output values: the rotation of the shaft The number and the angular position of the shaft within a given revolution.

There is a need for a multi-rotation rotation sensor system design to provide a single output measurement of object rotation at multiple rotations with high resolution, and be low-cost, small, and low-power.

This article describes a non-contact rotation sensing system and method for high-resolution and multi-rotation. The position sensing device may include a first rotating shaft coupled to the second rotating shaft, so that the rotation of the first rotating shaft causes the second rotating shaft to rotate. The first and second magnets can be coupled to the first and second rotating shafts, respectively. The first and second rotating shafts can be angularly moved relative to at least one magnetic sensor circuit that is not in contact with the first or second rotating shaft. The at least one magnetic sensor circuit can measure the angular positions of the first and second magnets to determine the angular position and the number of rotations of the first rotating shaft.

The embodiments described herein include a non-contact angular position sensing system and method for measuring the position of an object by measuring the rotation of an entrance shaft connected to the object. The described non-contact angular position sensing system and method use shaft-mounted magnets and one or more magnetic circuits to measure the rotation of the shaft over several revolutions. In one example, two magnets are embedded in two individual shafts, so that the magnetic circuit measures the magnetic fields of the magnets in two directions (longitudinal and transverse). In one example, the main shaft coupled to the external object drives the second shaft composed of sprocket through a screw. The screw and sprocket function as a reduction gear, where the larger sprocket makes the rotation of the second shaft slower than the smaller screw and therefore slower than the main shaft. Therefore, the rotational speed reduction between the main shaft and the second shaft is proportional to the ratio of the diameter of the screw to the sprocket. The reduction ratio between the two shafts makes it possible to determine the achievable number of revolutions of the sensor and the current of the sensor. The magnetic circuit generates one or more sensor output signals (for example, combined or separated signals) to provide the rotation angle of the external object coupled to the position sensor and the number of complete rotations of the external object .

The following shows and illustrates an example non-contact angular position sensing system, including some (but not all) possible components. The example non-contact angular position sensing system described and shown herein may include other components not shown, such as external objects, external systems, housings, shafts, gears, magnets, circuits, protective shields, power supplies, etc. . In addition, the components and the arrangement of the components are only examples and can be replaced by other components or arrangements with equivalent or identical functions. In addition, any components shown or described can be omitted.

FIG. 1 shows a high-level block diagram of an exemplary non-contact angular position sensing system 100 according to this description. The non-contact angular position sensing system 100 receives the (entry) movement 102 of the rotating object to be measured as input, and generates one or more output signals to indicate the angular position and the number of revolutions of the rotating object. In one example, the measurement signal 115 can provide the number of revolutions, and the measurement signal 113 can provide the precise angular position within the current revolution (for example, the angular position of the object between the 4th and 5th revolutions). Figure 1 shows three alternative example outputs based on the output signal 113 of the magnetic circuit 112 (for example, representing the rotational position of an object) and the output signal 115 of the magnetic circuit 114 (for example, representing the number of revolutions of the object): The combined output signal 116A produced by modulating the output signal 113 with the output signal 115; the combined output signal 116B produced by modulating the output signal 115 with the output signal 113 of the magnetic circuit; or two separate output signals 113 and 115 (That is, the signals are not combined). The movement 102 of the rotating object can be input to the system by coupling or connecting the rotating object to the first rotating shaft 104 that follows the movement of the rotating object. The first rotating shaft 104 is further coupled to the second rotating shaft 106 so that the rotation of the first shaft 104 will cause the second shaft 106 to rotate.

The first magnet 108 is coupled to the first shaft 104 and has a magnetized shaft integrated with the first shaft 104, so that the angular movement of the first shaft 104 will cause the angular rotation of the first magnet 108. For example, the first magnet 108 may be aligned such that the (first) magnetization axis of the first magnet 108 and the (first) longitudinal axis of the first shaft 104 are the same, or approximately the same. In this case, the north and south poles of the first magnet 108 are perpendicular to the rotation axis of the first shaft 104. Similarly, the second magnet 110 is coupled to the second shaft 106 and has a magnetized shaft integrated with the second shaft 106, so that the angular movement of the second shaft 106 will cause the angular rotation of the second magnet 110. For example, the second magnet 110 may be aligned such that the (second) magnetization axis of the second magnet 110 and the (second) longitudinal axis of the second shaft 106 are the same, or approximately the same. In this case, the north and south poles of the second magnet 110 are perpendicular to the rotation axis of the second shaft 106.

In an example, the rotating shafts 104 and 106 may be positioned non-parallel to each other (for example, a non-zero angle), so that the magnetic fields generated by the first and second magnets 108 and 110 are in different directions. For example, the first rotation shaft 104 may be positioned perpendicular (90 degree angle) to the second rotation shaft 106. In this case, the first magnetic field generated by the first magnet 108 is in the longitudinal direction relative to the first shaft 104 and the rotating object, and the second magnetic field generated by the second magnet 110 is relative to the first shaft 104 and the rotating object. The rotating object is in the horizontal direction.

The pivoted first and second magnets 108 and 110 move at an angle relative to the magnetic sensor circuits 112 and 114 (for example, they may be formed by one or more printed circuit boards (PCBs)). The magnetic sensor circuits 112 and 114 include processing electronics and/or protection electronics for measuring the angular position of the rotating shafts 104 and 106, and can perform additional processing, including but not limited to signal amplification and/or Analog to digital conversion. Although two magnetic sensor circuits 112 and 114 are shown in the figure, any number of magnetic sensor circuits (for example, one or more) can be used.

The magnetic sensor circuit 112 measures the rotation position of the first shaft 104 (and therefore the object) by sensing the magnetic field of the first magnet 108 to generate a first rotation measurement signal to indicate the first axis The rotation of the rod 104 on the number of revolutions of the first shaft 104. The output 113 of the magnetic sensor circuit 112 may be in an analog form, such as a voltage signal, or a digital form, such as a pulse width modulation (PWM) signal generated from the voltage signal. The magnetic sensor circuit 114 measures the rotation position of the second shaft 106 by sensing the magnetic field of the second magnet 110 to generate a second rotation measurement signal 115 of the second shaft 106 to represent the first shaft The number of revolutions of the rod 104 (and therefore the object). The magnetic sensor circuit 114 can generate an analog signal in volts for tracking the number of revolutions of the first shaft 104, and can convert the analog signal into a digital form. In an example, either or both of the magnetic sensor circuits 112 and 114 can use any of the following types of magnetic sensors to measure the magnetic fields corresponding to the magnets 108 and 110: Hall effect sensor, anisotropy Anisotropic Magnet Resistance (AMR) sensors, Giant Magnetoresistance (GMR) sensors, Tunnel Magneto Resistance (TMR) sensors. Although magnetic sensors are described; however, non-magnetic sensors may also be used, for example, absolute optical encoders. For example, an optical encoder can be used in the sensor circuit 112 or 114 to calculate the number of revolutions of the first shaft 104.

As discussed above, one or more output signals can be generated by the exemplary non-contact angular position sensing system 100, and three examples are shown in the figure. In an example, the first rotation measurement signal 113 of the first shaft 104 modulates the second rotation measurement signal 115 of the second shaft 106 to generate a single combined output signal 116A, which represents the angular rotation of the rotating object and The number of revolutions or revolutions (for example, see the example in Figure 8C). In another example, the second rotation measurement signal 115 of the second shaft 106 modulates the first rotation measurement signal 113 of the first shaft 104 to generate a single combined output signal 116B, which represents the angular rotation of the rotating object And the number of revolutions or revolutions (for example, see the example in Figure 7C). In another example, the signals 113 and 115 are provided as two separate outputs without combining them (for example, see the examples in FIGS. 7A and 7B or FIGS. 8A and 8B).

In one example, the analog measurement signal 115 provides the number of revolutions, and the analog measurement signal 113 provides the precise angular position within the current revolution (for example, the angular position of the object between the 4th and 5th revolutions). The resolution of the output signal (for example, the combined output signal 116A, the combined output signal 116B, or the signal 113 and the signal 115) depends on the magnetic sensor circuits 112 and 114 and the rotating shafts 104 and 106. In an example, the resolution of the digital output (116A, 116B, or 113 and 115) of the non-contact angular position sensing system 100 is a count of 12 bits per revolution of the object plus one revolution. In an example, if the magnetic sensor 112 for measuring the angular position of the object is a 10-rotation sensor, the resolution is log ₂ (10*2 ¹² ) = 15.32 bits, which is equivalent to 3600 ^. 40960 output values on the In another example, if the magnetic sensor 112 is a 16-rotation sensor, the resolution is log ₂ (16*2 ¹² ) = 16 bits, which is equivalent to 5760 ^. 65536 output values on the Therefore, the described non-contact angular position sensing system 100 can achieve high-resolution and high-accuracy rotation measurement.

FIG. 2 shows a cross-sectional view of an exemplary non-contact angular position sensing system 200 according to this description, showing the shaft rotation over time. The non-contact angular position sensing system 200 includes a first magnet 208 embedded in and longitudinally aligned with the input first rotary shaft 204 and a second rotary shaft embedded in and longitudinally aligned (invisible but located at the back, similar to FIG. 1 The second magnet 210 of the non-contact angular position sensing system 100). The first rotating shaft 204 is an input or inlet shaft connected to a rotating object (not shown). The horizontal axis of the first rotation shaft 204 is perpendicular to the horizontal axis of the second rotation shaft 206 coupled to the gear 207 (the second rotation shaft 206 in FIG. 2 is located behind the magnet 210). The first rotating shaft 204 further includes a screw 205 that rotates the second rotating shaft 206 through a gear 207. The diameter of the gear 207 is greater than the diameter of the first rotation shaft 204, and therefore, multiple rotations of the first rotation shaft 204 correspond to a single rotation of the second rotation shaft 206. In an example, the size ratio of the first rotating shaft 204 and the gear 207 is such that every ten revolutions of the first rotating shaft 204, the second rotating shaft 206 completes one revolution. Figure 2 illustrates the rotational positions of the shafts 204 and 206 and the magnets 208 and 210 over time (shown at three example time instances, t ₁ , t ₁ + t ₂ , and t ₁ + t ₂ + t ₃ , where , T ₁ , t ₂ , t ₃ > 0).

The non-contact angular position sensing system 200 includes a magnetic sensor circuit 212, which measures the angular position of the first rotating shaft 204 by sensing the magnetic field corresponding to the magnet 208. In this example, although the magnetic sensor circuit 212 is located at the opposite of the longitudinal axis of the first rotating shaft 204 (for example, so that the conductor of the Hall effect sensor is perpendicular to the electron flow direction of the magnetic field of the magnet 208 ); However, the magnetic sensor circuit 212 can also be located at other locations in the non-contact angular position sensing system 200. The non-contact angular position sensing system 200 includes a second magnetic sensor circuit, not shown in FIG. 2, which measures the angular position of the second rotating shaft 206. The second magnetic sensor circuit may be located at the opposite of the longitudinal axis of the second rotating shaft 206 (that is, opposite to the magnet 210). Although two magnetic sensor circuits are described in the figure; any number of magnetic sensor circuits (for example, one or more than two) can also be used.

In the example of FIG. 2, the shafts 204 and 206 are perpendicular to each other. FIG. 3 shows a cross-sectional view of an exemplary non-contact angular position sensing system 300 according to this description, in which the shafts 304 and 306 are parallel. The non-contact angular position sensing system 300 includes a first magnet 308 embedded in and longitudinally aligned with the first rotating input shaft 304 and a second magnet 310 embedded in and longitudinally aligned with the second rotating shaft 306. The first rotating shaft 304 is an input or inlet shaft connected to a rotating object (not shown). In this case, the horizontal axis of the first rotating shaft 304 is parallel to the horizontal axis of the second rotating shaft 306.

The gear 307 (for example, cogwheel, sprocket) centered and coupled to the second rotating shaft 306 is rotated by the screw 305 on the first rotating shaft 304, for example, by the interlocking screw 305 The threads and the teeth of the gear 307. In an example, the diameter of the gear 307 may be larger than the diameter of the first rotation shaft 304, and therefore, multiple rotations of the first rotation shaft 304 correspond to a single rotation of the second rotation shaft 306. In an example, the size ratio of the first rotating shaft 304 and the gear 307 is such that every ten revolutions of the first rotating shaft 304, the second rotating shaft 306 completes one revolution. In order to achieve each revolution of the gear 307, the input shaft 304 has a ratio of ten revolutions (or any number of revolutions, for example, 3, 5, or 16 revolutions). There is a mechanical match between the diameter of the threaded portion and the configuration of the gear 307 (for example, the number of teeth, the module, and/or the pitch). FIGS. 9A to 9E show different diagrams of exemplary screw rods that can be used on the input shaft 304, and FIGS. 10A to 10E show different diagrams of exemplary sprockets that can be used as gears 307. Fig. 9A shows a side cross-sectional view of the screw; Fig. 9B shows a side view of the screw; Fig. 9C shows a front cross-sectional view of the screw; and Figs. 9D and 9E show three-dimensional (3D) views of the screw from two different angles. Fig. 10A shows a side sectional view of the sprocket; Fig. 10B shows a side view of the sprocket; Fig. 10C shows a front sectional view of the sprocket; and Figs. 10D and 10E show 3D views of the sprocket from two different angles. Figures 9A to 9E and 10A to 10E are only examples, and other types of gears can also be used.

Referring to FIG. 3, the magnetic sensor circuits 312 and 314 respectively located at the opposite positions of the longitudinal axes of the first and second rotating shafts 304 and 306 measure the shafts 304 and 314 by sensing the magnetic fields of the corresponding magnets 308 and 310 306's angular position. The exemplary non-contact angular position sensing system 300 further includes a housing 320 and a shield 322 to provide protection between the magnets 308 and 310 and/or between the magnetic sensor circuits 312 and 314. For example, the shield 322 may be made of a specific material, such as soft iron, and may have a specific shape and thickness to block the external magnetic field. Unnecessary magnetic fields that should be blocked can include parasitic magnetic fields or magnetic fields imposed by other neighboring components in the same or neighboring systems.

FIG. 4 shows a three-dimensional (3D) diagram of an exemplary non-contact angular position sensing system 400 with a vertical shaft according to this description. The configuration of the exemplary non-contact angular position sensing system 400 generally corresponds to the exemplary non-contact angular position sensing system 200 shown in FIG. 2. Figure 4 shows that the components of the non-contact angular position sensing system 400 are separated into two parts under the housing 420a and the housing 420b to illustrate the internal components; however, when implemented, the housing 420a and the housing 420b are One-piece continuous housing (see housing 420 in FIG. 5), and screw 405 interlocking sprocket 407 (equivalent to the arrangement of housing 220, screw 205, gear 207, and other components shown in FIG. 2) . In an example, the housing 420a and the housing 420b can be made into two parts with a joint plane, and then can be combined together to form the final integrated housing 420. More generally, the housing 420 can be made into one or several accessories.

The angular position of the external object (not shown) is defined by the rotation of the inlet shaft 404 coupled to the second shaft 406 inside the housings 420a and 420b and the internal electronics including the magnetic sensor circuits 412 and 414. At least a part (for example, all) of the inlet shaft 404 is located in the housing 420a and at least a part (for example, all) of the second shaft 406 is located in the housings 420a and 420b. For example, the shape of the inlet shaft 404 and/or the second shaft 406 may be a cylinder or a cube. The inlay of the housing parts 420 a and 420 b can provide a guide for the second shaft 406.

The inlet shaft 404 may include a portion with a screw 405, and the second shaft 406 may include a portion with a sprocket 407 (for example, inlaid to the end of the second shaft 406). In an example, the entire inlet shaft 404 may be a screw 405, and/or the entire second shaft 406 may be a sprocket 407. The inlet shaft 404 is coupled to an external object, and the second shaft 406 is driven through the screw 405 by rotating the sprocket 407. By correctly selecting the inclination angle of the tooth portion of the sprocket 407 and the mesh portion of the screw 405, the central axis of the sprocket 407 can be positioned at any position relative to the screw 405. In an example, the central axis of the sprocket 407 can be at 90 angles of the screw 405 (as shown in FIGS. 2, 4, and 5); however, any other mechanically feasible angles can be used under the premise of achieving the desired reduction ratio. The reduction ratio between the inlet shaft 404 and the second shaft 406 depends on the reduction ratio between the screw 405 and the sprocket 407, and more specifically, the number of threads on the screw 405 and the sprocket 407 The ratio of the number of teeth. Therefore, the reduction ratio can be set by selecting the thread on the screw 405 relative to the teeth on the sprocket. The reduction ratio allows the internal electronics to determine the number of revolutions of the object and the electric stroke of the magnets 408 and 410.

The non-contact angular position sensing system 400 measures the rotation of the shaft 404 over several revolutions. The magnets 408 and 410 including the internal electronic coupling of the magnetic sensor circuits 412 and 414 and the shafts 404 and 406 are integrated to measure the magnetic field in the longitudinal and transverse directions relative to the shaft 404 and the rotating object. The degree of rotation (N degrees) of the second shaft 406 is proportional to the number of rotations of the first shaft 404.

The spindle rod 404 and the magnet 408 are integrated, and the magnetization axis of the magnet 408 is consistent with the longitudinal axis of the spindle rod 404. The second shaft 406 and the magnet 410 are integrated, and the magnetization axis of the magnet 410 is perpendicular to the longitudinal axis of the main shaft 404. The housings 420a and 420b include a threaded fastening system (or bushing) 434 at the main shaft 404 for fixing, guiding, and/or holding the main shaft 404 to the housing 420a. The threaded fastening system 434 allows the adjustment and coaxiality of the external rotating object or system and the inlet shaft 404, and can be configured or adjusted by the user. The threaded fastening system 434 can be used to embed the non-contact angular position sensing system 400 to an external structure or system.

The magnetic circuits 412 and 414 can be embedded in the positions 430 and 432 of the housings 420a and 420b, respectively, and generate and provide output signals to the user through the terminal 426 (for example, to the user processor and/or user interface ). One or more screws 423 can be used to fix the two parts of the housing 420a and 420b together (other mechanisms other than screws can be used, such as ultrasonic welding).

The housings 420a and 420b may correspond to the exemplary integrated housing 420 shown in FIG. 5. The outer side and/or the inner side of the housing 420 may have curved surfaces (for example, if the housing 420a and 420b are formed using a die casting method) to match the manufacturing process. The housing 420 includes a position 442 for inserting the bushing 434, a position 444 for inserting the second shaft 406, and a position 446 for inserting the output terminal 426. In an example, the housing 420 may be a molded plastic part, and may be made by 3D printing or may be an assembly of several parts. In one example, the bushing 434 can be embedded in the housing 420, or over-molded with the plastic housing 420a, or crimped.

Referring to FIG. 4, the magnetic circuits 412 and 414 can be formed on separate PCBs and embedded at different positions 430 and 432 opposite to the respective shafts 404 and 406. The magnetic sensor circuit 412 measures the rotation position of the first shaft 404 (and therefore the object) by sensing the magnetic field of the first magnet 408 to generate a first rotation measurement signal. The magnetic sensor circuit 414 measures the rotation position of the second shaft 406 by sensing the magnetic field of the second magnet 410 to generate a second rotation measurement signal of the second shaft 406 to indicate the first shaft 104 and therefore the number of revolutions of the object.

An additional circuit system (not shown) connecting the magnetic circuits 412 and 414 allows the magnetic circuit 412 to provide the first rotation measurement signal of the first shaft 404 to the second magnetic sensor circuit 414. The second magnetic sensor circuit 414 combines the first rotation measurement signal of the first shaft 404 and the second rotation measurement signal of the second shaft 406 to generate a combined output signal representing the angular rotation and rotation of the rotating object Number or revolutions. The second magnetic sensor circuit 414 can provide a combined output signal to the user through the output terminal 426. Although the magnetic sensor circuits 412 and 414 shown in FIG. 4 are located at two positions 430 and 432 and on separate PCBs; however, for example, the entire magnetic sensor circuit can be implemented on a common PCB or One or more than two PCBs (for example, the circuit for combining the first and second rotation measurement signals can be located on the third PCB).

FIG. 6 shows a functional block diagram of an exemplary internal electronic component 600 that can be used in a non-contact angular position sensing system according to this description. For example, internal electronic components can be implemented in the magnetic sensor circuit shown in FIGS. 1 to 4 and one or more PCBs. The internal electronic component 600 measures the magnetic field of the shaft magnet, processes the measurement (for example, combines measurement, converts the signal from analog to digital, etc.), protects the sensor circuit, and generates and provides a representation of the rotation of the object Combined output signal 616. Power is supplied to data processing microcircuits 652 and 662, where V+ is a high input voltage (for example, +5V or +10V) and V- is a low input voltage (for example, equal to 0V or -5V to ground) .

The magnetic sensor circuit 612 may be an integrated circuit and may include a data processing microcircuit 652 to measure the rotation of the entrance shaft and provide a digital first rotation measurement signal 653 to indicate that the entrance shaft follows The angular position of the time rotation. For example, the data processing microcircuit 652 may include a Hall-effect sensor that generates a voltage proportional to the magnetic field of the magnet passing through it, and converts the measured voltage into an angular position of the entrance shaft that rotates with time. The circuit system of the electrical signal 653 (for example, the PWM signal).

The magnetic sensor circuit 614 may be an integrated circuit and may include a data processing microcircuit 662 for measuring the rotation of the second shaft and providing the second rotation measurement signal 663 in an analog form. For example, the data processing microcircuit 662 may include a Hall effect sensor that generates an analog voltage signal 663 proportional to the magnetic field of the magnet passing through it from the second sensor on the second shaft. The sensor protection circuits 654 and 664 can provide protection against harmful effects, such as reverse polarity, overvoltage, or transients.

The combination circuit 675 can combine the rotation PWM signal 655 on the main shaft of the entrance shaft and the analog signal 665 representing the rotation number of the entrance shaft by obtaining the product of the two signals (for example, the Bollinger multiplication, The PWM signal at the low level (for example, 0V) is regarded as logic "0", and the PWM signal at the high level (for example, 1V or 5V) is regarded as logic "1") to generate the combined output signal 616, which represents the rotation of the object Angular rotation and number of rotations or revolutions. The combined output signal 616 can be read by the user interface to provide the user with the angular rotation of the rotating object coupled to the position sensor. Examples of the PWM signal 655, the analog signal 665, and the combined output signal 616 on the N rotation of the entrance shaft are shown in FIGS. 7A to 7C. In an example, the PWM signal 655 may have 360 degrees ^. The range and 0.09 ^. The resolution of the analog signal 665 can be 3,600 ^. The range and 1 ^. The resolution of the combined output signal 616 can be 3,600 ^. The range and 0.09 ^. Resolution. Although the combined output signal 616 is shown; however, the PWM signal 655 and the analog signal 665 can also be provided as separate outputs (analog form or converted to digital form).

The duty cycle of the PWM signal 655 endows the angular position of the entrance shaft with high accuracy (because of high resolution and fine mechanics). The amplitude of the analog signal 665 (in volts) is proportional to the number of revolutions completed by the inlet shaft, where 1/N revolution of the second shaft corresponds to 1 revolution of the inlet shaft (that is, N is the gear ratio Or reduction ratio). The analog signal 665 is modulated by the PWM 655 to generate a combined output signal 616, which provides angular position information and the number of rotations.

7A to 7C show examples of the shape and type (analog vs. digital) of the signal from the sensing circuit (for example, analog/analog), so that other combinations of the shape and type of the signal can be mixed with a suitable electronic device. In order to obtain a single output signal containing several pieces of information, including the number of revolutions completed and the angular position of the revolution in progress with good resolution. 8A to 8C show another set of example measurement signals on the N rotation of the entrance shaft of the alternative configuration shown in FIG. 6. In the example of FIGS. 8A to 8C, the magnetic circuit coupled to the magnet of the entrance shaft supplies an analog signal 855 (in volts). The amplitude of the analog signal 855 provides the angular position of the entrance shaft within each revolution of the entrance shaft with high accuracy. The magnetic circuit coupled with the magnet of the second shaft supplies the PWM signal 865 so that the duty cycle of the PWM signal 865 provides the number of revolutions of the first shaft. The analog signal 855 is modulated by the PWM signal 865 (that is, the product of the PWM signal 865 and the analog signal 855) to generate a combined output signal 816, including the angular position and rotation of the first shaft (and the corresponding rotating object) The precision of the number. As explained above, the combination of PWM signal and analog signal is not necessary, and a separate signal can be provided as output.

In any of the examples described herein, redundant sensor circuits can be used to provide more robust measurement information. For example, two separate magnetic sensing circuits can be used in the housing of the non-contact position sensing system, so as to provide two independent and redundant output signals. Angular position with good resolution and the number of revolutions completed. In another example, different combinations of different types of magnetic sensing circuits can be implemented in the same non-contact angular position sensing system, for example, using Hall effect sensors and magnetoresistive sensors at the same time. In the examples described herein, the size and combination of components can be adjusted according to user requirements (for example, size, length, and attachment mode).

100: Non-contact angular position sensing system 102: Movement of rotating objects 104: The first rotating shaft/rotating shaft/first shaft 106: second rotating shaft/rotating shaft/second shaft 108: The first magnet/magnet 110: second magnet/magnet 112: Magnetic circuit/magnetic sensor circuit/sensor circuit/magnetic sensor 113: measurement signal/output signal/output/first rotation measurement signal/signal/analog measurement signal 114: Magnetic circuit/magnetic sensor circuit/sensor circuit 115: measurement signal/output signal/second rotation measurement signal/signal/analog measurement signal 116A, 116B: combined output signal 200: Non-contact angular position sensing system 204: The first rotating shaft/shaft 205: Screw 206: second rotating shaft/shaft 207: Gear 208: The first magnet/magnet 210: second magnet/magnet 212: Magnetic Sensor Circuit 300: Non-contact angular position sensing system 304: first rotating shaft/shaft/input shaft 305: Screw 306: second rotating shaft/shaft 307: Gear 308: first magnet/magnet 310: second magnet/magnet 312: Magnetic Sensor Circuit 314: Magnetic Sensor Circuit 320: shell 322: Shield 400: Non-contact angular position sensing system 404: Entry shaft/shaft/first shaft/spindle 405: Screw 406: second shaft/shaft 407: Sprocket 408: Magnet 410: Magnet/Second Magnet 412: Magnetic circuit/magnetic sensor circuit 414: Magnetic circuit/magnetic sensor circuit/second magnetic sensor circuit 420: Shell 420a: shell/shell part/shell part 420b: Shell/shell part 423: Screw 426: output terminal 430, 432: Location 434: With threaded fastening system/bushing 442, 444, 446: location 600: Internal electronic components 612: Magnetic Sensor Circuit 614: Magnetic Sensor Circuit 616: Combined output signal 652: Data Processing Microcircuit 653: The first rotation measurement signal / electrical signal 654: Sensor protection circuit 655: PWM signal 662: Data Processing Microcircuit 663: The second rotation measurement signal / analog voltage signal 664: Sensor protection circuit 665: Analog Signal 675: Combination Circuit

Figure 1 shows a high-level block diagram of an exemplary non-contact angular position sensing system according to this record;

Figure 2 shows a cross-sectional view of an exemplary non-contact angular position sensing system with a vertical shaft according to this description and illustrates the shaft rotation over time;

Figure 3 shows a cross-sectional view of an exemplary non-contact angular position sensing system with parallel shafts according to the content of this record;

Figure 4 shows a three-dimensional (3D) diagram of an exemplary non-contact angular position sensing system with a vertical shaft according to the content of this record;

Figure 5 shows an exemplary integrated housing that can be used in a non-contact angular position sensing system according to the content of this record;

FIG. 6 shows a functional block diagram of an example internal electronic component that can be used in a non-contact angular position sensing system according to the content of this record;

Figures 7A to 7C show a set of example measurement signals on the N-turn of the entrance shaft according to this record;

Figures 8A to 8C show another set of example measurement signals on the N-turn of the entrance shaft according to this record;

Figures 9A to 9E show different diagrams of example worm screws that can be used on the input shaft according to the content of this record; and

Figures 10A to 10E show different diagrams of exemplary sprocket wheels that can be used as gears according to this description.

Read the accompanying detailed description and refer to the accompanying drawings to understand the foregoing and other viewpoints, advantages, and novel features of the recorded teachings. In the figures, the same components have the same component symbols.

100: Non-contact angular position sensing system

102: Movement of rotating objects

104: The first rotating shaft/rotating shaft/first shaft

106: second rotating shaft/rotating shaft/second shaft

108: The first magnet/magnet

110: second magnet/magnet

112: Magnetic circuit/magnetic sensor circuit/sensor circuit/magnetic sensor

113: measurement signal/output signal/output/first rotation measurement signal/signal/analog measurement signal

114: Magnetic circuit/magnetic sensor circuit/sensor circuit

115: measurement signal/output signal/second rotation measurement signal/signal/analog measurement signal

116A, 16B: combined output signal

Claims (20)

A position sensing device includes: The first rotating shaft has a first longitudinal axis; A second rotation shaft having a second longitudinal shaft, the first rotation shaft being coupled to the second rotation shaft, so that the rotation of the first rotation shaft causes the second rotation shaft to rotate; A first magnet coupled to the first rotating shaft and having a first magnetization axis aligned with the first longitudinal axis of the first rotating shaft; A second magnet coupled to the second rotating shaft and having a second magnetization axis aligned with the second longitudinal axis of the second rotating shaft; and At least one magnetic sensor circuit is not in contact with the first rotating shaft and not in contact with the second rotating shaft, wherein the first rotating shaft and the second rotating shaft are opposite to the at least one A magnetic sensor circuit performs angular movement, and wherein the at least one magnetic sensor circuit is configured to: Measuring the angular position of the first magnet to generate a first angular measurement value, Measuring the angular position of the second magnet to generate a second angular measurement value representing the number of rotations of the first rotating shaft, and The first angle measurement value and the second angle measurement value are combined to generate a combined angle measurement value, which represents the angular position of the first rotating shaft and the number of rotations of the rotating shaft. The position sensing device according to claim 1, wherein the first rotating shaft is coupled to an external rotating object to drive the rotation of the first rotating shaft. The position sensing device according to claim 1, wherein the first rotating shaft includes a portion with a screw, the second rotating shaft includes a portion with a sprocket, and wherein the rotation of the screw causes The sprocket rotates. The position sensing device according to claim 3, wherein the reduction ratio between the first rotating shaft and the second rotating shaft and the number of threads of the screw and the number of teeth of the sprocket The ratio is directly proportional. The position sensing device according to claim 4, wherein the resolution of the combined angle measurement value depends on the reduction ratio between the first rotating shaft and the second rotating shaft. In the position sensing device according to claim 1, the at least one magnetic sensor circuit includes a data processor circuit system and a sensor protection circuit system. The position sensing device according to claim 1, wherein the at least one magnetic sensor circuit includes at least one microcircuit. The position sensing device according to claim 1, wherein the at least one magnetic sensor circuit is located on at least one printed circuit board (PCB). The position sensing device according to claim 1, wherein the at least one magnetic sensor circuit includes at least one Hall effect sensor configured to measure the first magnet and the second magnet Magnetic field. The position sensing device according to claim 1, wherein the at least one magnetic sensor circuit includes: The first magnetic sensor circuit is located at the opposite of the first longitudinal axis of the first rotating shaft and is configured to measure the first magnet by sensing the magnetic field of the first magnet The angular position of; and A second magnetic sensor circuit, located at the opposite of the second longitudinal axis of the second rotating shaft and configured to measure the first magnet by sensing the magnetic field of the second magnet Of the angular position. The position sensing device according to claim 10, wherein the first magnetic sensor circuit is configured to generate a relationship with the rotation of the first rotating shaft based on the angular position of the first magnet Proportional digital pulse width modulation (PWM) signal. The position sensing device according to claim 11, wherein the second magnetic sensor circuit is configured to generate a relationship with the rotation of the second rotating shaft based on the angular position of the second magnet Proportional analog signal. The position sensing device according to claim 12, wherein the second magnetic sensor circuit is further configured to obtain the product of the digital electrical pulse width modulation (PWM) signal and the analog electrical signal The first angle measurement value and the second angle measurement value are combined. The position sensing device according to claim 10, wherein the first magnetic sensor circuit is configured to generate a relationship with the rotation of the first rotating shaft based on the angular position of the first magnet Proportional analog signal. The position sensing device according to claim 14, wherein the second magnetic sensor circuit is configured to generate a relationship with the rotation of the second rotating shaft based on the angular position of the second magnet Proportional digital pulse width modulation (PWM) signal. The position sensing device according to claim 15, wherein the second magnetic sensor circuit is further configured to obtain the product of the digital electrical pulse width modulation (PWM) signal and the analog electrical signal The first angle measurement value and the second angle measurement value are combined. The position sensing device according to claim 1, further comprising a housing that surrounds at least part of the first rotating shaft, the second rotating shaft, the first magnet, the second magnet, And the at least one magnetic sensor circuit. The position sensing device according to claim 17, wherein the housing further includes a threaded end configured to guide and hold the first rotating shaft. The position sensing device according to claim 17, wherein the housing further includes a curved wall portion. The position sensing device according to claim 1, further comprising: At least one output terminal is used to provide the combined angle measurement value to the user.

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