Absolute encoders and their position acquisition methods, motors and automation equipment

Abstract

This invention discloses an absolute encoder, its position acquisition method, a motor, and an automation device. The absolute encoder includes a circuit board and magnetic and optical elements movable relative to the circuit board. The circuit board includes: a magnetic induction module configured to sense changes in the magnetic field of the magnetic element and generate a magnetically encoded signal; an optical induction module configured to sense changes in the optical signal of the optical element and generate an optically encoded signal; and a signal processing module configured to receive and process the magnetically encoded signal and the optically encoded signal, and obtain a second absolute position of the absolute encoder at the current moment based on the first absolute position, the relative position, and the values ​​of the first, second, or third revolutions. This invention solves the problem of the complex process of measuring position information in current optical-magnetic hybrid encoders, while meeting the requirements of high precision and anti-interference.

Description

Technical Field

[0001] This invention relates to the field of encoders, and more specifically to an absolute encoder and its position acquisition method, a motor, and automation equipment. Background Technology

[0002] An optical encoder is a sensor that converts the mechanical geometric displacement on an output shaft into an electrical analog or digital quantity through photoelectric conversion. It is the most widely used sensor and consists of a light source, a code disk, and a photosensitive element. The code disk is a circular plate of a certain diameter with several rectangular holes evenly spaced. Because the code disk is coaxial with the motor, the code disk rotates at the same speed as the motor. A detection device composed of LEDs and other electronic components detects and outputs several analog or pulse signals. By calculating the number of analog or pulse signals output by the optical encoder per second, the current motor speed can be reflected. However, optical encoders have the following disadvantages: they require higher protection in outdoor and harsh environments; measuring linear displacement relies on mechanical conversion, necessitating the elimination of errors caused by mechanical backlash; and detecting objects moving on a track is difficult due to slippage.

[0003] Magnetoelectric encoders use magnetoresistive elements to measure the angle or displacement of changing magnetic materials. Changes in the angle or displacement of the magnetic material cause changes in resistance or voltage. These changes are processed by a microcontroller, which then outputs pulse or analog signals to achieve the measurement purpose. Magnetoelectric encoders overcome the shortcomings of photoelectric encoders and offer advantages such as shock resistance, corrosion resistance, pollution resistance, high reliability, and simple structure. However, their accuracy is relatively poor.

[0004] In the prior art, the optical-magnetic hybrid encoder can make up for the shortcomings of the above-mentioned photoelectric encoder and magnetoelectric encoder. However, the existing optical-magnetic hybrid encoder has problems such as a more complex process for measuring position information, low accuracy, and poor resistance to interference. Summary of the Invention

[0005] The purpose of this invention is to provide an absolute encoder, a motor, and an automation device to solve the problems existing in the prior art.

[0006] To address the aforementioned problems, according to a first aspect of the present invention, an absolute encoder is provided, the absolute encoder comprising a circuit board and magnetic and optical elements movable relative to the circuit board, the circuit board comprising:

[0007] A magnetic induction module, configured to sense changes in the magnetic field of the magnetic element and generate a magnetically encoded signal;

[0008] A light-sensing module, configured to sense changes in the light signal of the optical element and generate an optically encoded signal; and

[0009] The signal processing module is configured to:

[0010] Receive and process the magnetic encoding signal to obtain the first absolute position of the absolute encoder at the current time, or the first absolute position at the current time and the first or second revolution value;

[0011] Receive and process the optically encoded signal to obtain the relative position of the absolute encoder at the current moment, or the relative position at the current moment and the value of the third cycle; and

[0012] The second absolute position of the absolute encoder at the current moment is obtained based on the first absolute position, the relative position, and the first, second, or third revolution value.

[0013] Preferably, the magnetically encoded signal includes at least one first sine and cosine signal group. Within one mechanical cycle, the first sine and cosine signal group includes X cycles of first sine signals and X cycles of first cosine signals, where X ≥ 1 and X is an integer; or

[0014] At least one first square wave signal group, which includes Y periods of first square wave signal and Y periods of second square wave signal within one mechanical cycle, wherein Y≥1 and Y is an integer.

[0015] Preferably, the magnetically encoded signal includes:

[0016] The signal processing module receives and processes a combination of digital signals that vary with angular position or stroke period to obtain the first absolute position and the first revolution value of the absolute encoder at the current moment; or

[0017] The first Z-pulse signal is received and processed by the signal processing module to obtain the second revolution value of the absolute encoder at the current moment; or

[0018] A PWM signal that varies with angular position or stroke period; or

[0019] A triangular wave signal that varies with angular position or stroke period; or

[0020] At least four trapezoidal wave signals that vary with angular position or travel period.

[0021] Preferably, the optically encoded signal includes:

[0022] At least one second sine and cosine signal group, wherein within one mechanical cycle, the second sine and cosine signal group comprises V cycles of second sine signals and V cycles of second cosine signals, where V ≥ 1 and V is an integer; or

[0023] At least one second square wave signal group, which includes a third square wave signal of U periods and a fourth square wave signal of U periods within one mechanical cycle, wherein U ≥ 1 and U is an integer.

[0024] Preferably, the phase difference between the first sine signal and the first cosine signal in each of the first sine and cosine signal groups at the same time is 90 degrees ± 45 degrees; or

[0025] The phase difference between the first square wave signal and the second square wave signal in each first square wave signal group at the same time is 90 degrees ± 45 degrees.

[0026] Preferably, the phase difference between the second sine signal and the second cosine signal in each second sine / cosine signal group at the same moment is 90 degrees ± 45 degrees; or

[0027] The phase difference between the third square wave signal and the fourth square wave signal in each of the second square wave signal groups at the same time is 90 degrees ± 45 degrees.

[0028] Preferably, the optical encoding signal further includes a second Z-pulse signal, and the signal processing module receives and processes the second Z-pulse signal to obtain the third cycle value of the absolute encoder at the current moment.

[0029] Preferably, the absolute encoder includes a code disk with code tracks, and the light sensing module is used to sense changes in the light signal of the code disk to generate the optical encoded signal; and / or, the absolute encoder includes an annular grating with code tracks, and the light sensing module is used to sense changes in the light signal of the annular grating to generate the optical encoded signal; and / or, the absolute encoder includes an arc-shaped grating with code tracks, and the light sensing module is used to sense changes in the light signal of the arc-shaped grating to generate the optical encoded signal; and / or, the absolute encoder includes a cylindrical grating with code tracks, and the light sensing module is used to sense changes in the light signal of the cylindrical grating to generate the optical encoded signal; and / or, the absolute encoder includes a conical grating with code tracks, and the light sensing module is used to sense changes in the light signal of the conical grating to generate the optical encoded signal; and / or, the absolute encoder includes a grating ruler with code tracks, and the light sensing module is used to sense changes in the light signal of the grating ruler to generate the optical encoded signal.

[0030] Preferably, the light emitted by the light sensing module is received by the light sensing module after being reflected by the code track; or, the absolute encoder further includes a light source for emitting light, and the light emitted by the light source is received by the light sensing module after being reflected or transmitted by the code track.

[0031] Preferably, the code track is any one of vernier code track, Gray code track, M-sequence or other pseudo-random sequence code track, and single-cycle code track.

[0032] Preferably, the magnetic induction module includes a Hall element and / or a magnetic induction chip, wherein the magnetic induction chip includes at least one of HALL, AMR, GMR and TMR.

[0033] Preferably, the absolute encoder includes at least one of a magnet, a magnetic disc, a magnetic ring, a magnetic tile, a magnetic drum, or a magnetic ruler; the magnetic induction module is used to sense the magnetic field change of at least one of the magnet, the magnetic disc, the magnetic ring, the magnetic tile, the magnetic drum, and the magnetic ruler to generate the magnetic encoding signal.

[0034] According to a second aspect of the invention, a motor is provided, the motor comprising the absolute encoder described in any of the preceding claims.

[0035] According to a third aspect of the present invention, an automated device is provided, the automated device comprising the motor described above.

[0036] According to a fourth aspect of the present invention, a method for obtaining the second absolute position of an absolute encoder at the current moment is provided.

[0037] The method includes:

[0038] It senses changes in magnetic fields and generates magnetically encoded signals, and senses changes in optical signals and generates optically encoded signals;

[0039] Receive and process the magnetic encoded signal to obtain the first absolute position of the absolute encoder at the current moment, or the first absolute position at the current moment and the value of the first or second revolution;

[0040] Receive and process the optically encoded signal to obtain the relative position of the absolute encoder at the current moment, or the relative position at the current moment and the value of the third cycle; and

[0041] The second absolute position of the absolute encoder at the current moment is obtained based on the first absolute position, the relative position, and the first, second, or third revolution value.

[0042] Preferably, obtaining the second absolute position of the absolute encoder at the current moment based on the first absolute position, the relative position, and the first, second, or third revolution value includes:

[0043] The second absolute position angle of the absolute encoder at the current moment is obtained based on the first absolute position angle, the relative position angle, and the first, second, or third revolution value.

[0044] Preferably, when the first absolute position angle and the relative position angle satisfy the first condition, the second absolute position angle is calculated according to the following formula:

[0045] θ3=n×360°+θ1+θ2 / 2 a ,

[0046] Wherein, θ1 is the first absolute position angle, θ2 is the relative position angle, n is the value of the first revolution, the value of the second revolution, or the value of the third revolution (n is an integer), θ3 is the second absolute position angle, and

[0047] The first condition is:

[0048] The first absolute position angle θ1 satisfies: -360° < θ1 < 360°, and the resolution of θ1 is 360° / 2. a (a≥0, a is an integer) and θ1 have a period of 1 (within one mechanical cycle), and

[0049] The second absolute position angle θ2 satisfies: -360° < θ2 < 360°, and the resolution of θ2 is 360° / 2. b (b≥0, b is an integer) and the period of θ2 is 2 a (Within one mechanical cycle).

[0050] Preferably, when the first absolute position angle and the relative position angle satisfy the second condition, the second absolute position angle is calculated according to the following formula:

[0051] θ3 = n × 360° + θ1 + θ2,

[0052] Wherein, θ1 is the first absolute position angle, θ2 is the relative position angle, n is the value of the first revolution, the value of the second revolution, or the value of the third revolution (n is an integer), θ3 is the second absolute position angle, and

[0053] The second condition is:

[0054] The first absolute position angle θ1 satisfies: 0°≤θ1<360° and the resolution of θ1 is 360° / 2. a (a≥0, a is an integer), and

[0055] The second absolute position angle θ2 satisfies: -360° < θ2 < 360°, and the resolution of θ2 is 360° / 2.b (b≥0, b is an integer) and the period of θ2 is 1 (within one mechanical cycle).

[0056] The beneficial effects of this invention are that the absolute encoder of this invention not only combines the advantages of photoelectric encoders and magnetoelectric encoders, but also solves the problem of the complex process of measuring position information in current photoelectric-magnetic hybrid encoders, while meeting the requirements of high precision and anti-interference. Attached Figure Description

[0057] Figure 1 This is a schematic diagram of an absolute encoder structure according to an embodiment of the present invention;

[0058] Figure 2 This is a schematic diagram of the absolute encoder workflow according to an embodiment of the present invention. Detailed Implementation

[0059] The preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings, so as to better understand the purpose, features and advantages of the present invention. It should be understood that the embodiments shown in the drawings are not intended to limit the scope of the present invention, but are only for illustrating the essential spirit of the technical solution of the present invention.

[0060] In the following description, certain specific details are set forth for the purpose of illustrating various disclosed embodiments in order to provide a thorough understanding of the various disclosed embodiments. However, those skilled in the art will recognize that embodiments may be practiced without one or more of these specific details. In other instances, well-known apparatuses, structures, and techniques associated with this application may not have been shown or described in detail to avoid unnecessarily obscuring the description of the embodiments.

[0061] Throughout this specification, references to "an embodiment" or "an embodiment" indicate that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment. Therefore, the appearance of "in an embodiment" or "an embodiment" in various places throughout the specification does not necessarily refer to the same embodiment. Furthermore, a particular feature, structure, or characteristic may be combined in any manner in one or more embodiments.

[0062] In the following description, in order to clearly demonstrate the structure and working method of the present invention, a number of directional terms will be used. However, terms such as "front", "back", "left", "right", "outside", "inside", "outward", "inward", "up", and "down" should be understood as convenient terms and not as limiting terms.

[0063] One embodiment of the present invention provides an absolute encoder, referring to... Figure 1 and Figure 2The absolute encoder includes a circuit board 103, and a magnetic element 101 and an optical element 102 that are movable relative to the circuit board 103. The circuit board 103 includes a magnetic induction module 104, a light induction module 105, and a signal processing module 106. The magnetic induction module 104 is used to sense the magnetic field change of the magnetic element 101 and generate a magnetic encoding signal. The light induction module 105 is used to sense the light signal change of the optical element 102 and generate a light encoding signal. The signal processing module 106 is used to receive and process the magnetic encoding signal to obtain the first absolute position of the absolute encoder at the current moment, or the first absolute position at the current moment and the first or second revolution value. The signal processing module 106 is also used to receive and process the light encoding signal to obtain the relative position of the absolute encoder at the current moment, or the relative position at the current moment and the third revolution value. The signal processing module 106 then obtains the second absolute position of the encoder at the current moment based on the first absolute position, the relative position, and the first or second or third revolution value.

[0064] In other words, in some embodiments, the signal processing module 106 is used to receive and process magnetically encoded signals to obtain the first absolute position and first revolution value of the absolute encoder at the current moment. The signal processing module 106 is also used to receive and process optically encoded signals to obtain the relative position of the absolute encoder at the current moment. The signal processing module 106 is configured to obtain the second absolute position of the encoder at the current moment based on the first absolute position, relative position, and first revolution value.

[0065] In other embodiments, the signal processing module 106 is configured to receive and process magnetically encoded signals to obtain a first absolute position and a second revolution value of the absolute encoder at the current moment. The signal processing module 106 is also configured to receive and process optically encoded signals to obtain the relative position of the absolute encoder at the current moment. Finally, the signal processing module 106 is configured to obtain a second absolute position of the encoder at the current moment based on the first absolute position, the relative position, and the second revolution value.

[0066] In some embodiments, the signal processing module 106 is configured to receive and process magnetically encoded signals to obtain the first absolute position of the absolute encoder at the current moment. The signal processing module 106 is also configured to receive and process optically encoded signals to obtain the relative position and third revolution value of the absolute encoder at the current moment. Furthermore, the signal processing module 106 is configured to obtain the second absolute position of the encoder at the current moment based on the first absolute position, relative position, and third revolution value.

[0067] Specifically, for example, the signal processing module 106 receives and processes the magnetically encoded signal to obtain the first absolute position angle θ1 and the first revolution value n1 at the current moment, where -360° < θ1 < 360°, and n1 is an integer. The resolution of the angle θ1 is 360° / 2. a Where a ≥ 0, and a is an integer. Within one mechanical cycle, the period of the angle θ1 is 1. The signal processing module 106 simultaneously receives and processes the optically encoded signal to obtain the relative position angle θ2 at the current moment, where -360° < θ2 < 360°. The resolution of the angle θ2 is 360° / 2. b Where b ≥ 0, and b is an integer. Specifically, within one mechanical cycle, the angle θ2 changes exactly 2... a One cycle. Based on the first absolute position angle θ1, the first cycle value n1, and the relative position angle θ2, the second absolute position of the encoder at the current moment can be obtained, where the second absolute position angle θ3 = n1 × 360° + θ1 + (360° / 2)^2. a )×(θ2 / 360°)=n1×360°+θ1+θ2 / 2 a .

[0068] Specifically, for example, the signal processing module 106 receives and processes the magnetically encoded signal to obtain the first absolute position angle θ0 at the time of power-on (to distinguish it from θ1 in the above embodiment, it will not be described again below) and the first rotation value n1 at the current time, where 0°≤θ0<360°, and n1 is an integer. The resolution of the angle θ0 is 360° / 2. a Where a ≥ 0, and a is an integer. The signal processing module 106 simultaneously receives and processes the optically encoded signal to obtain the relative position angle θ2 at the current moment, where -360° < θ2 < 360°. The resolution of the angle θ2 is 360° / 2. b Where b≥0, and b is an integer. Within one mechanical cycle, the period of the angle θ2 is 1. The second absolute position of the encoder at the current moment can be obtained based on the first absolute position angle θ0, the first revolution value n1, and the relative position angle θ2, and the second absolute position angle θ3=n1×360°+θ0+θ2.

[0069] Specifically, for example, the signal processing module 106 receives and processes the magnetically encoded signal to obtain the first absolute position angle θ1 and the second revolution value n2 at the moment of power-on, where -360° < θ1 < 360°, and n2 is an integer. The resolution of the angle θ1 is 360° / 2. aWhere a ≥ 0, and a is an integer. Within one mechanical cycle, the period of the angle θ1 is 1. The signal processing module 106 simultaneously receives and processes the optically encoded signal to obtain the relative position angle θ2 at the current moment, where -360° < θ2 < 360°. The resolution of the angle θ2 is 360° / 2. b Where b ≥ 0, and b is an integer. Specifically, within one mechanical cycle, the angle θ2 changes exactly 2... a One cycle. Based on the first absolute position angle θ1, the second cycle value n2, and the relative position angle θ2, the second absolute position of the encoder at the current moment can be obtained. The second absolute position angle value θ3 = n2 × 360° + θ1 + (360° / 2) a )×(θ2 / 360°)=n2×360°+θ1+θ2 / 2 a .

[0070] Specifically, for example, the signal processing module 106 receives and processes the magnetically encoded signal to obtain the first absolute position angle θ0 at the time of power-on and the second rotation value n2 at the current time, where 0°≤θ0<360° and n2 is an integer. The resolution of the angle θ0 is 360° / 2. a Where a ≥ 0, and a is an integer. The signal processing module 106 simultaneously receives and processes the optically encoded signal to obtain the relative position angle θ2 at the current moment, where -360° < θ2 < 360°. The resolution of the angle θ2 is 360° / 2. b Where b≥0, and b is an integer. Within one mechanical cycle, the period of the angle θ2 is 1. The second absolute position of the encoder at the current moment can be obtained based on the first absolute position angle θ0, the second revolution value n2, and the relative position angle θ2, and the second absolute position angle θ3=n2×360°+θ0+θ2.

[0071] Specifically, for example, the signal processing module 106 receives and processes the magnetically encoded signal to obtain the first absolute position angle θ1 at the current moment, where -360° < θ1 < 360°. The resolution of the angle θ1 is 360° / 2. a Where a ≥ 0, and a is an integer. Within one mechanical cycle, the period of the angle θ1 is 1. The signal processing module 106 simultaneously receives and processes the optically encoded signal to obtain the relative position angle θ2 at the current moment and the value of the third cycle n3, where -360° < θ2 < 360°, and n3 is an integer. The resolution of the angle θ2 is 360° / 2. b Where b ≥ 0, and b is an integer. Specifically, within one mechanical cycle, the angle θ2 changes exactly 2... aOne cycle. Based on the first absolute position angle θ1, the third cycle value n3, and the relative position angle θ2, the second absolute position of the encoder at the current moment can be obtained. The second absolute position angle θ3 = n3 × 360° + θ1 + (360° / 2) a )×(θ2 / 360°)=n3×360°+θ1+θ2 / 2 a .

[0072] Specifically, for example, the signal processing module 106 receives and processes the magnetically encoded signal to obtain the angle θ0 of the first absolute position at the moment of power-on, where 0° ≤ θ0 < 360°. The resolution of the angle θ0 is 360° / 2. a Where a ≥ 0, and a is an integer. The signal processing module 106 simultaneously receives and processes the optically encoded signal to obtain the relative position angle θ2 at the current moment and the third circle value n3, where -360° < θ2 < 360°, and n3 is an integer. The resolution of the angle θ2 is 360° / 2. b Where b≥0, and b is an integer. Within one mechanical cycle, the period of the angle θ2 is 1. The second absolute position of the encoder at the current moment can be obtained based on the first absolute position angle θ0, the third cycle value n3, and the relative position angle θ2, where the second absolute position angle θ3=n3×360°+θ0+θ2.

[0073] The circuit board 103, the magnetic induction module 104, and the light induction module 105 can be one or more.

[0074] Through this design, the absolute encoder of the present invention not only combines the advantages of photoelectric encoders and magnetoelectric encoders, but also solves the problem of the complex process of measuring position information in current photoelectric-magnetic hybrid encoders, while meeting the requirements of high precision and anti-interference.

[0075] In one embodiment of the present invention, the magnetically encoded signal includes at least one first sine and cosine signal group. Within one mechanical cycle, the first sine and cosine signal group includes a first sine signal with X cycles and a first cosine signal with X cycles, where X ≥ 1 and X is an integer.

[0076] With this design, within one mechanical cycle, the first sine and cosine signal group (first sine signal and first cosine signal) generated and output by the magnetic induction module corresponds one-to-one with the first absolute position of the absolute encoder at the current moment, or the first absolute position at the current moment and the value of the first revolution or the value of the second revolution. Therefore, by calculating the first sine and cosine signal group (first sine signal and first cosine signal), the first absolute position of the absolute encoder at the current moment, or the first absolute position at the current moment and the value of the first revolution or the value of the second revolution, can be directly obtained.

[0077] It should be noted that when an absolute encoder is installed in a rotary motor, the first sine and cosine signal group, comprising X cycles of the first sine and cosine signals within one mechanical cycle, means that for every one revolution (360 degrees) the magnetic element rotates with the rotor of the rotary motor, the magnetic induction module outputs X cycles of the first sine and cosine signals. Similarly, when an absolute encoder is installed in a drum motor, the same principle applies to the magnetic element. When an absolute encoder is installed in a linear motor, the same principle applies to the magnetic element.

[0078] In one embodiment of the present invention, the magnetically encoded signal includes at least one first square wave signal group. Within one mechanical cycle, the first square wave signal group includes a first square wave signal with Y cycles and a second square wave signal with Y cycles, wherein Y≥1 and Y is an integer.

[0079] With this design, within one mechanical cycle, the first square wave signal group (first square wave signal and second square wave signal) output by the magnetic induction module corresponds one-to-one with the first absolute position of the absolute encoder at the current moment, or the first absolute position at the current moment and the value of the first revolution or the value of the second revolution. Therefore, by calculating the first square wave signal group (first square wave signal and second square wave signal) of the magnetic induction module, the first absolute position of the encoder's magnetic signal at the current moment, or the first absolute position at the current moment and the value of the first revolution or the value of the second revolution, can be directly obtained.

[0080] It should be noted that when an absolute encoder is installed in a rotary motor, within one mechanical cycle, the first square wave signal group, consisting of Y cycles of first square wave signal and Y cycles of second square wave signal, means that for every one revolution (360 degrees) the magnetic element rotates with the rotor of the rotary motor, the magnetic induction module outputs Y cycles of first square wave signal and Y cycles of second square wave signal. When an absolute encoder is installed in a drum motor, within one mechanical cycle, the first square wave signal group, consisting of Y cycles of first square wave signal and Y cycles of second square wave signal, means that for every one revolution (360 degrees) the magnetic element rotates with the rotor of the drum motor, the magnetic induction module outputs Y cycles of first square wave signal and Y cycles of second square wave signal. When an absolute encoder is installed in a linear motor, within one mechanical cycle, the first square wave signal group, consisting of Y cycles of first square wave signal and Y cycles of second square wave signal, means that for every one stroke the magnetic element moves with the rotor of the linear motor, the magnetic induction module outputs Y cycles of first square wave signal and Y cycles of second square wave signal.

[0081] In one embodiment of the present invention, the specific waveform of the magnetically encoded signal differs from that in the embodiments described above. In this embodiment, the magnetically encoded signal includes a combination of digital signals that vary with angular position or stroke period. The signal processing module receives and processes the combination of digital signals to obtain the first absolute position and the first revolution value of the absolute encoder at the current moment. The combination of digital signals that varies with angular position or stroke period can be one or more.

[0082] In one embodiment of the present invention, the specific waveform of the magnetic encoding signal is different from that in the above embodiments. In this embodiment, the magnetic encoding signal includes a first Z pulse signal. The signal processing module receives and processes the first Z pulse signal to obtain the second revolution value of the absolute encoder at the current moment. The first Z pulse signal can be one or more.

[0083] In one embodiment of the present invention, the specific waveform of the magnetically encoded signal is different from that in the above embodiments. In this embodiment, the magnetically encoded signal includes a PWM signal that varies with the angular position or travel period, wherein the PWM signal can be one or more.

[0084] In one embodiment of the present invention, the specific waveform of the magnetically encoded signal is different from that in the above embodiments. In this embodiment, the magnetically encoded signal includes a triangular wave signal that varies with the angular position or travel period, wherein the triangular wave signal can be one or more.

[0085] In one embodiment of the present invention, the specific waveform of the magnetically encoded signal is different from that in the above embodiments. In this embodiment, the magnetically encoded signal includes at least four trapezoidal wave signals that vary with angular position or travel period.

[0086] In one embodiment of the present invention, the optically encoded signal includes at least one second sine and cosine signal group. Within one mechanical cycle, the second sine and cosine signal group includes a second sine signal with V cycles and a second cosine signal with V cycles, wherein V ≥ 1 and V is an integer.

[0087] With this design, within one mechanical cycle, the second sine and cosine signal group (second sine signal and second cosine signal) generated and output by the photosensitive module corresponds one-to-one with the current position of the absolute encoder, or the current position and the value of the third cycle. Therefore, by calculating the second sine and cosine signal group (second sine signal and second cosine signal), the current position of the absolute encoder, or the current position and the value of the third cycle, can be directly obtained.

[0088] It should be noted that when an absolute encoder is installed in a rotary motor, the second sine and cosine signal group, comprising V cycles of the second sine and cosine signals within one mechanical cycle, means that for every one revolution (360 degrees) the optical element rotates with the rotor of the rotary motor, the photosensitive module outputs V cycles of the second sine and cosine signals. Similarly, when an absolute encoder is installed in a drum motor, the same applies to the photosensitive module. When an absolute encoder is installed in a linear motor, the same applies to the photosensitive module.

[0089] In one embodiment of the present invention, the optically encoded signal includes at least one second square wave signal group. Within one mechanical cycle, the second square wave signal group includes a third square wave signal with U cycles and a fourth square wave signal with U cycles, wherein U ≥ 1 and U is an integer.

[0090] With this design, within one mechanical cycle, the second square wave signal group (third square wave signal and fourth square wave signal) output by the photosensitive module corresponds one-to-one with the current position of the absolute encoder, or the current position and the third cycle value. Therefore, by calculating the second square wave signal group (third square wave signal and fourth square wave signal) of the photosensitive module, the current position of the encoder, or the current position and the third cycle value, can be directly obtained.

[0091] It should be noted that when an absolute encoder is installed in a rotary motor, within one mechanical cycle, the second square wave signal group includes U cycles of third and fourth square wave signals. This means that for every one revolution (360 degrees) the optical element rotates with the rotor of the rotary motor, the photosensitive module outputs U cycles of third and fourth square wave signals. When an absolute encoder is installed in a drum motor, within one mechanical cycle, the second square wave signal group includes U cycles of third and fourth square wave signals. This means that for every one revolution (360 degrees) the optical element rotates with the rotor of the drum motor, the photosensitive module outputs U cycles of third and fourth square wave signals. When an absolute encoder is installed in a linear motor, within one mechanical cycle, the second square wave signal group includes U cycles of third and fourth square wave signals. This means that for every one stroke the optical element moves with the rotor of the linear motor, the photosensitive module outputs U cycles of third and fourth square wave signals.

[0092] In one embodiment of the present invention, the phase difference between the first sine signal and the first cosine signal of each first sine and cosine signal group at the same time is 90 degrees ± 45 degrees.

[0093] In one embodiment of the present invention, the phase difference between the first square wave signal and the second square wave signal in each first square wave signal group at the same time is 90 degrees ± 45 degrees.

[0094] In one embodiment of the present invention, the phase difference between the second sine signal and the second cosine signal of each second sine and cosine signal group at the same time is 90 degrees ± 45 degrees.

[0095] In one embodiment of the present invention, the phase difference between the third square wave signal and the fourth square wave signal in each second square wave signal group at the same time is 90 degrees ± 45 degrees.

[0096] In one embodiment of the present invention, the optical encoding signal further includes a second Z-pulse signal, and the signal processing module receives and processes the second Z-pulse signal to obtain the third cycle value of the absolute encoder at the current moment.

[0097] In one embodiment of the present invention, the absolute encoder includes a code disk with code tracks, and the light sensing module is used to sense changes in the light signal of the code disk to generate the light-coded signal.

[0098] In one embodiment of the present invention, the absolute encoder includes an annular grating with code tracks, and a light sensing module is used to sense changes in the light signal of the annular grating to generate a light-coded signal.

[0099] In one embodiment of the present invention, the absolute encoder includes an arc-shaped grating with code tracks, and a light sensing module is used to sense changes in the light signal of the arc-shaped grating to generate a light-coded signal.

[0100] In one embodiment of the present invention, the absolute encoder includes a cylindrical grating with code tracks, and a light sensing module is used to sense changes in the light signal of the cylindrical grating to generate a light-coded signal.

[0101] In one embodiment of the present invention, the absolute encoder includes a tapered grating with code tracks, and a light sensing module is used to sense changes in the light signal of the tapered grating to generate a light-coded signal.

[0102] In one embodiment of the present invention, the absolute encoder includes a grating ruler with code tracks, and the light sensing module is used to sense changes in the light signal of the grating ruler to generate the light-coded signal.

[0103] In one embodiment of the present invention, the light emitted by the photosensitive module is received by the photosensitive module after being reflected by the code channel.

[0104] In one embodiment of the present invention, the absolute encoder further includes a light source for emitting light, wherein the light emitted by the light source is received by a light sensing module after being reflected or transmitted through the code track.

[0105] In one embodiment of the present invention, the code channel is any one of vernier code channel, Gray code channel, M-sequence or other pseudo-random sequence channel, and single-cycle code channel.

[0106] In one embodiment of the present invention, the magnetic induction module includes a Hall element and / or a magnetic induction chip, wherein the magnetic induction chip includes at least one of HALL, AMR, GMR and TMR.

[0107] In one embodiment of the present invention, the absolute encoder includes at least one of a magnet, a magnetic disc, a magnetic ring, a magnetic tile, a magnetic drum, or a magnetic ruler; the magnetic induction module is used to sense the magnetic field change of at least one of the magnet, magnetic disc, magnetic ring, magnetic tile, magnetic drum, and magnetic ruler to generate a magnetic encoding signal.

[0108] According to the above embodiments of the absolute encoder, one embodiment of the present invention provides a method for obtaining the second absolute position of the absolute encoder at the current moment, comprising the following steps:

[0109] Step S1: Sensing changes in the magnetic field and generating a magnetically encoded signal; sensing changes in the optical signal and generating an optically encoded signal;

[0110] Step S2: Receive and process the magnetic encoding signal to obtain the first absolute position of the absolute encoder at the current moment, or the first absolute position at the current moment and the value of the first or second revolution;

[0111] Step S3: Receive and process the optically encoded signal to obtain the relative position of the absolute encoder at the current moment, or the relative position at the current moment and the value of the third cycle; and

[0112] Step S4: Based on the first absolute position, relative position, and the first, second, or third cycle value at the current moment, obtain the second absolute position of the absolute encoder at the current moment.

[0113] In one embodiment of the present invention, in step S4, the second absolute position angle of the absolute encoder at the current moment is obtained based on the first absolute position angle, the relative position angle, and the first revolution value, the second revolution value, or the third revolution value at the current moment.

[0114] In one embodiment of the present invention, when the first absolute position angle and the relative position angle satisfy the first condition, the second absolute position angle is calculated according to the following formula:

[0115] θ3=n×360°+θ1+θ2 / 2 a ,

[0116] Where θ1 is the first absolute position angle, θ2 is the relative position angle, n is the value of the first, second, or third revolution (n is an integer), θ3 is the second absolute position angle, and the first condition is:

[0117] The first absolute position angle θ1 satisfies: -360°≤θ1<360°, and the resolution of θ1 is 360° / 2. a (a≥0, a is an integer) and θ1 have a period of 1 (within one mechanical cycle), and

[0118] The second absolute position angle θ2 satisfies: -360° < θ2 < 360°, and the resolution of θ2 is 360° / 2. b (b≥0, b is an integer) and the period of θ2 is 2 a (Within one mechanical cycle).

[0119] In this embodiment, when n represents the value of the first revolution, the value of the second revolution, or the value of the third revolution, the specific calculation method of the second absolute position angle has been described in the above embodiment of the absolute encoder, and will not be repeated in this embodiment.

[0120] In one embodiment of the present invention, when the first absolute position angle and the relative position angle satisfy a second condition, the second absolute position angle is calculated according to the following formula:

[0121] θ3 = n × 360° + θ1 + θ2,

[0122] Wherein, θ1 is the first absolute position angle, θ2 is the relative position angle, n is the value of the first revolution, the value of the second revolution, or the value of the third revolution (n is an integer), θ3 is the second absolute position angle, and the second condition is:

[0123] The first absolute position angle θ1 satisfies: 0° < θ1 < 360° and the resolution of θ1 is 360° / 2. a (a≥0, a is an integer), and

[0124] The second absolute position angle θ2 satisfies: -360° < θ2 < 360°, and the resolution of θ2 is 360° / 2. b (b≥0, b is an integer) and the period of θ2 is 1 (within one mechanical cycle).

[0125] In this embodiment, when n represents the value of the first revolution, the value of the second revolution, or the value of the third revolution, the specific calculation method of the second absolute position angle has been described in the above embodiment of the absolute encoder, and will not be repeated in this embodiment.

[0126] One embodiment of the present invention provides a motor that includes the absolute encoder described in the above embodiment.

[0127] One embodiment of the present invention provides an automated device, which includes the motor described in the above embodiment.

[0128] The preferred embodiments of the present invention have been described in detail above. However, it should be understood that after reading the above teachings, those skilled in the art can make various alterations or modifications to the present invention. These equivalent forms also fall within the scope defined by the appended claims.

Claims

1. An absolute value encoder comprising a circuit board and a magnetic element and an optical element movable relative to the circuit board, characterized in that, The circuit board comprises: a magnetic induction module configured to induce a magnetic field change of the magnetic element and generate a magnetic encoding signal; a light induction module configured to induce a light signal change of the optical element and generate a light encoding signal; and a signal processing module configured to: receive and process the magnetic encoding signal to obtain a first absolute position angle of the absolute value encoder at a current time, or a first absolute position angle and a first or second number of turns at a current time; the magnetic encoding signal comprises a digital signal combination or a first Z-pulse signal varying with an angular position or a stroke period; the signal processing module receives and processes the digital signal combination to obtain the first absolute position and the first number of turns of the absolute value encoder at the current time; or the signal processing module receives and processes the first Z-pulse signal to obtain the second number of turns of the absolute value encoder at the current time; receive and process the light encoding signal to obtain a relative position angle of the absolute value encoder at a current time, or a relative position angle and a third number of turns at a current time; and obtain a second absolute position angle of the absolute value encoder at a current time according to the first absolute position angle, the relative position angle, and the first or second or third number of turns at the current time; when the first absolute position angle and the relative position angle satisfy a first condition, the second absolute position angle is calculated according to the following formula: θ3 = n x 360 o + θ1 + θ2 / 2 a , where θ1 is the first absolute position angle, θ2 is the relative position angle, n is the first or second or third number of turns, θ3 is the second absolute position angle, and the first condition is: said first absolute position angle θ1 fulfils: -360 o < θ1 < 360 o , the resolution of θ1 is 360 o / 2 a and the period of θ1 within one mechanical cycle is 1, wherein a > 0, a is an integer, and The relative position angle θ2 satisfies: -360 o < θ2 < 360 o The resolution of θ2 is 360 o / 2 b And in one mechanical cycle, the angle θ2 changes exactly 2 a cycles, where b ≥ 0, b is an integer. when the first absolute position angle and the relative position angle satisfy a second condition, the second absolute position angle is calculated according to the following formula: θ3 = n x 360 o + θ1 + θ2, where θ1 is the first absolute position angle, θ2 is the relative position angle, n is the first or second or third number of turns, θ3 is the second absolute position angle, and the second condition is: The first absolute position angle θ1 satisfies: 0 o ≤ θ1 < 360 o and the resolution of θ1 is 360 o / 2 a where a ≥ 0, a is an integer, and The relative position angle θ2 satisfies: -360 o ≤ θ2 < 360 o , the resolution of θ2 is 360 o / 2 b , and the period of θ2 in one mechanical cycle is 1, b ≥ 0, and b is an integer.

2. The absolute value encoder of claim 1, wherein The magnetic encoding signal comprises: at least one first cosine signal group, which comprises X cycles of a first cosine signal and X cycles of a first sine signal in one mechanical period, where X≥1, X is an integer; or at least one first square wave signal group, which comprises Y cycles of a first square wave signal and Y cycles of a second square wave signal in one mechanical period, where Y≥1, Y is an integer.

3. The absolute value encoder of claim 1, wherein, The magnetic encoding signal comprises: a PWM signal varying with an angular position or a stroke period; or a triangular wave signal varying with an angular position or a stroke period; or at least four trapezoidal wave signals varying with an angular position or a stroke period.

4. The absolute value encoder of claim 1, wherein, The light encoding signal comprises: at least one second cosine signal group, which comprises V cycles of a second cosine signal and V cycles of a second sine signal in one mechanical period, where V≥1, V is an integer; or at least one second square wave signal group, which comprises W cycles of a second square wave signal and W cycles of a third square wave signal in one mechanical period, where W≥1, W is an integer. At least one second square wave signal group, the second square wave signal group comprising U third square wave signals and U fourth square wave signals in one mechanical cycle, wherein U≥1, U is an integer.

5. The absolute value encoder of claim 2, wherein, The phase difference between the first sine signal and the first cosine signal of each first positive cosine signal group at the same time is 90 degrees ± 45 degrees; or The phase difference between the first square wave signal and the second square wave signal in each first square wave signal group at the same time is 90 degrees ± 45 degrees.

6. The absolute value encoder of claim 4, wherein, The phase difference between the second sine signal and the second cosine signal of each second positive cosine signal group at the same time is 90 degrees ± 45 degrees; or The phase difference between the third square wave signal and the fourth square wave signal in each second square wave signal group at the same time is 90 degrees ± 45 degrees.

7. The absolute value encoder of claim 1, wherein, The optical encoding signal further comprises a second Z pulse signal, and the signal processing module receives and processes the second Z pulse signal to obtain the third number of turns of the absolute value encoder at the current time.

8. An electric machine characterized by The motor comprises the absolute value encoder according to any one of claims 1 to 7.

9. An automated apparatus, characterized by, The automation device comprises the motor according to claim 8.

10. A method of acquiring a second absolute position of an absolute value encoder, characterized by, The method comprises the following steps: Step one, sensing magnetic field changes and generating a magnetic encoding signal, and sensing optical signal changes and generating an optical encoding signal; Step two, receiving and processing the magnetic encoding signal to obtain a first absolute position angle of the absolute value encoder at the current time, or a first absolute position angle at the current time and a first number of turns or a second number of turns; the magnetic encoding signal comprises a digital signal combination or a first Z pulse signal that varies with the angle position or the stroke cycle; the signal processing module receives and processes the digital signal combination to obtain the first absolute position and the first number of turns of the absolute value encoder at the current time; or the signal processing module receives and processes the first Z pulse signal to obtain the second number of turns of the absolute value encoder at the current time; Step three, receiving and processing the optical encoding signal to obtain a relative position angle of the absolute value encoder at the current time, or a relative position angle at the current time and a third number of turns; and Step four, obtaining a second absolute position angle of the absolute value encoder at the current time according to the first absolute position angle at the current time, the relative position angle, and the first number of turns or the second number of turns or the third number of turns; When the first absolute position angle and the relative position angle satisfy a first condition, the second absolute position angle is calculated according to the following formula: θ3 = n x 360 o + θ1 + θ2 / 2 a , Wherein, θ1 is the first absolute position angle, θ2 is the relative position angle, n is the first number of turns or the second number of turns or the third number of turns, θ3 is the second absolute position angle, and The first condition is: said first absolute position angle θ1 fulfils: -360 o < θ1 < 360 o , the resolution of θ1 is 360 o / 2 a and the period of θ1 within one mechanical cycle is 1, wherein a > 0, a is an integer, and The relative position angle θ2 satisfies: -360 o < θ2 < 360 o The resolution of θ2 is 360 o / 2 b And in one mechanical cycle, the angle θ2 changes exactly 2 a cycles, where b ≥ 0, b is an integer. When the first absolute position angle and the relative position angle satisfy a second condition, the second absolute position angle is calculated according to the following formula: θ3 = n x 360 o + θ1+ θ2, wherein θ1 is the first absolute position angle, θ2 is the relative position angle, n is the first number of turns or the second number of turns or the third number of turns, θ3 is the second absolute position angle, and the second condition is: The first absolute position angle θ1 satisfies: 0 o ≤ θ1 < 360 o and the resolution of θ1 is 360 o / 2 a where a ≥ 0, a is an integer, and The relative position angle θ2 satisfies: -360 o ≤ θ2 < 360 o , the resolution of θ2 is 360 o / 2 b , and the period of θ2 in one mechanical cycle is 1, b ≥ 0, and b is an integer.

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