CN203274770U - Integrated encoder for rotor location detection of motor and valve location stroke detection of valve - Google Patents

Abstract

The utility model discloses an encoder integrating motor rotor position detection and valve position stroke detection, which comprises a stroke input shaft, a stroke input gear, a base, a control circuit and the like. By setting a coaxial device at the coaxial end of the motor, the first layer increases the speed through a 1:5 speed-increasing gear plate, and then continuously reads out the binary 8-bit absolute code corresponding to the code plate through the code-fetching circuit of the photoelectric sensor The value is used as the position detection of the motor rotor; the second, third, and fourth layers first reduce the speed through the deceleration chainring with a total ratio of 40 to 1, and then continuously read out the second, third, and fourth layers through the photoelectric sensor code-fetching circuit. The binary 16-bit absolute code corresponding to the rotation position of the code disc in the layer is sent to the level conversion circuit, and finally the detected rotor position signal and valve opening signal are shaped by the optocoupler and sent to the corresponding processor as logic Judging the use, so that the high-precision detection of the motor position and the valve position can be realized on one encoder at the same time.

Description

An encoder integrating motor rotor position detection and valve position stroke detection

technical field

The utility model relates to a motor rotor position detection and a valve stroke detection of a valve electric actuator system, in particular to an encoder integrating the position detection of a switched reluctance motor rotor and the stroke position detection of a valve position.

Background technique

The valve electric actuator based on the switched reluctance motor is a new type of valve electric actuator with strong functions and high reliability. It can meet the needs of high-end control requirements in nuclear power plants, thermal power plants, and petrochemical industries. The high-reliability switched reluctance motor controller is selected to effectively control the speed of the motor, and to realize accurate and reliable positioning of the valve stroke in process control, and to realize good protection of the valve and the actuator. Therefore, the position detection and valve stroke detection of the switched reluctance motor are important research contents to ensure the reliability and accuracy of the system.

The purpose of the position detection of the switched reluctance motor is to determine the relative position of the stator and the rotor to control the corresponding phase winding on and off; the common position detectors include photosensitive type, magnetic sensitive type and proximity switch, etc. The rotor position detection part of the switched reluctance motor adopts a photoelectric position sensor. The photoelectric position sensor is composed of two parts: a slot-type photocoupler and a gear plate with the same structure as the motor rotor. The gear plate is coaxially installed with the motor, and the gear plate The teeth of the tooth plate can freely pass through the U-shaped groove of the slot-type optocoupler; when the teeth of the tooth plate block the optical path of the slot-type optocoupler, the optocoupler is in the cut-off state, and when the groove of the tooth plate passes through the slot-type optocoupler, the optocoupler’s The optical path is opened, and the optocoupler is in the conduction state; therefore, when the motor rotor rotates continuously (the gear plate also rotates with the rotor at the same speed), the three slot-type optocouplers will output three-way signals, and after the shaping of the peripheral circuit, three-way and Square wave signal related to rotor position. The stroke detection of the valve is through the stroke input shaft and the stroke input gear, and adopts the principle of photoelectric conversion. The code fetching circuit of the photoelectric sensor continuously reads out the binary 16-bit absolute code corresponding to the rotation position of the code disc, and sends it to the level conversion circuit. The level signal is shaped by the optocoupler, converted into a 0-30V voltage and output to the control system outside the stroke controller, and the angular displacement of the stroke output shaft is converted into a corresponding digital value, thereby confirming the absolute position of the valve.

The tooth plate of the above-mentioned existing switched reluctance motor position detection device is the same size as the motor rotor, which is not easy to be miniaturized, and the switched reluctance motor position detection and valve stroke detection mechanisms are separately arranged, which not only occupies the valve The space of the electric actuator increases the failure rate of the detection device and reduces the accuracy and reliability of the detection.

Contents of the invention

The utility model is just to solve the above problems, and provides a detection encoder capable of detecting the rotor position of the switched reluctance motor and the valve position stroke at the same time. It satisfies the requirements of actual control precision; and solves the problem of realizing the rotor position detection of the switched reluctance motor and the valve position detection of the electric valve on the output shaft side of the motor.

The technical solution of the utility model:

An encoder integrating motor rotor position detection and valve position stroke detection, comprising a stroke input shaft, a stroke input gear, a base, and a control circuit composed of a photoelectric sensor code fetching circuit and a level conversion circuit, on the stroke input shaft Fix the stroke input gear, speed-up gear and deceleration gear. The speed-up gear meshes with the first layer of counting gear at the rotor position of the motor, and the 1~4-digit code is fixed under the first layer of counting gear at the rotor position. Disk and the first code fetching circuit; the gear meshing with the first layer of counting gear at the rotor position drives the second layer of counting gear at the rotor position to rotate, and the 5~8-digit code is fixed under the second layer of counting gear at the rotor position disc and the second code fetching circuit; the reduction gear meshes with the first bottom counting gear of the valve position, and the first to fourth code discs and the third code fetching circuit are fixed on the first bottom counting gear of the valve position, The gear meshed with the first bottom counting gear of the valve position drives the second bottom counting gear of the valve position to rotate; the 5th to 8th code disc and the fourth code fetching circuit are fixed on the second bottom counting gear of the valve position, and The second intermediate gear meshed with the second bottom counting gear of the valve position drives the first top counting gear to rotate, and the 9th to 12th code disc and the fifth code fetching circuit are fixed under the first top counting gear. The first intermediate gear meshed with the first top floor counting gear drives the second top floor counting gear to rotate, and the 13th to 16th code discs and the sixth code fetching circuit are fixed under the second top floor counting gear.

A coaxial device is installed at the coaxial end of the switched reluctance motor. The first layer increases the speed through a 1:5 speed-up toothed disc, and then continuously reads out the binary 8 bits corresponding to the code disc through the code-fetching circuit of the photoelectric sensor. Absolute code value is used as motor rotor position detection. The second, third, and fourth layers first reduce the rotation speed through the deceleration toothed disc with a total ratio of 40 to 1; The corresponding binary 16-bit absolute code is sent to the level conversion circuit; finally, the detected rotor position signal and valve opening signal are shaped by the optocoupler and sent to the corresponding processor for logic judgment, so that it can be used in a The encoder realizes the high-precision detection of motor position detection and valve position detection at the same time.

The integrated encoder adopts a multi-turn absolute encoder, and encodes by Gray code, and a reflective photoelectric sensor is set under the code disc.

Compared with the prior art, the utility model has the beneficial effects: by combining the motor position detection with the valve position detection, the high-precision motor position detection and the valve position detection of the valve are realized; the multi-turn absolute encoder is adopted, And it is coded by Gray code. When converting the code value, when changing from any number to an adjacent number, only one digit changes. If there is an error in any code track, as long as the error is not too large, and only possible There is a reading error in one of the code channels, and the resulting error is at most equal to one bit of the lowest bit, which reduces the misreading rate; adopts the parallel port signal transmission method, outputs the pulse signal according to the rotation angle, and converts the output pulse signal into a position signal; thus realizing the position Increased detection resolution and power down do not affect the acquisition of encoded data.

Description of drawings

Figure 1: Schematic diagram of the structure and principle of the utility model encoder.

Figure 2: Schematic diagram of the structure and principle of the Gray code encoding disc of the present invention.

Fig. 3: The circuit diagram of output coding value adjustment of the utility model.

Figure 4: Schematic diagram of the structure and principle of the multi-turn encoder of the utility model.

Detailed ways

The utility model will be further described below in conjunction with the accompanying drawings and embodiments.

The motor rotor position detection and valve position stroke detection integrated encoder of this embodiment is to realize the rotor position detection of the switched reluctance motor with 12/8 structure and the valve position detection of the valve driven by the switched reluctance motor.

As shown in Figure 1, the integrated encoder for motor rotor position detection and valve position stroke detection includes stroke input shaft 2, stroke input gear 1, base 3, a control circuit composed of a photoelectric sensor code fetching circuit and a level conversion circuit, an incremental The speed gear 5 and the reduction gear 6, the speed increase gear 5 meshes with the first layer of counting gear 29 at the rotor position of the motor, and the first layer of counting gear 29 at the rotor position is fixed below the 1~4 bit code disc 22 and the first code fetching Circuit 21; the gear meshed with the first layer of counting gear 29 at the rotor position drives the second layer of counting gear 27 at the rotor position to rotate, and the second layer of counting gear 27 at the rotor position is fixed below the second layer of counting gear 27 followed by 5 to 8 code discs 26 and the second Code fetching circuit 24; reduction gear 6 is meshed with the first bottom counting gear 28 of the valve position, the first to fourth code discs 8 and the third code fetching circuit 9 are fixed on the first bottom bottom counting gear 28 of the valve position, and the valve The gear meshed with the first bottom counting gear 28 drives the second bottom counting gear 17 of the valve position to rotate; the 5th to 8th code disc 16 and the fourth code fetching circuit 20 are fixed on the second bottom counting gear 17 of the valve position, The second intermediate gear 15 meshed with the second bottom counting gear 17 of the valve position drives the first top counting gear 11 to rotate, and is fixed under the first top counting gear 11 to connect the 9th to 12th code disc 10 and the fifth code fetching circuit 10. The first intermediate gear 14 meshed with the first top counting gear 11 drives the second top counting gear 18 to rotate, and the 13th to 16th code disc 19 and the sixth code fetching circuit are fixed under the second top counting gear 18 20.

In the detection of the rotor position of the switched reluctance motor, an 8-bit absolute encoder is used, which is divided into two 4-bit code discs. The schematic diagram of the code disc is shown in Figure 2, and four reflective photoelectric sensors are arranged under each code disc. , respectively corresponding to 4-bit code values, when the code wheel is rotated to black, there is no reflected light, and the output is high level, when it is white, there is reflected light, and the output is low level, thus forming a pulse square wave, and then through the conditioning shown in Figure 3 The value of the circuit output code disc; in Fig. 1, the code disc 22 of the rotor position 1 ~ 4 is the lower four bits, and the code disc 26 of the rotor position 5 ~ 8 is the high four bits, and in Fig. The number of teeth of the first layer counting gear 29 is 48 to 240. Since the motor rotor has 8 poles and the stator has 12 poles, the rotation angle of one step is 7.5°, so the number of teeth is set to 48=360°/7.5°; and by 1 to 5 According to the speed increase, the motor rotates 7.5° to increase the speed to obtain 1.5°=360°/240, that is, the encoder will generate 5 code values for every 7.5° rotation to determine the angle of rotation of the motor, thus improving the resolution.

In the valve position detection, since there is a 40-to-1 reducer between the motor output shaft and the valve, in the valve position detection device on the motor side, the speed is reduced to The valves are consistent, and then read the valve position value of 360° through the 16-bit encoder, and the detection accuracy is 360°/2 ¹⁶ =0.00549°; the 16-bit encoder passes four 4-bit code discs as shown in Figure 2 Composition, its principle is consistent with the code disc in the above-mentioned motor rotor position detection device and will not be redundant here.

Figure 3 shows the code fetching signal conditioning circuit. The working principle of the conditioning circuit is to amplify the code fetching signal through the operational amplifier TL082, and then invert and shape the code fetching signal through the inverter CD4069 to obtain the coded value.

Both the rotor position detection and the valve position detection in the utility model adopt the multi-turn absolute encoder as shown in Fig. At this time, another set of code discs (or multiple sets of gears, multiple sets of code discs) is driven by gears, and the code of the number of turns is added on the basis of single-turn coding to expand the measuring range of the encoder, which is determined by the mechanical position Coding, each position code is unique and does not repeat, without memory.

Claims (4)

1. An encoder integrating motor rotor position detection and valve position stroke detection, including a stroke input shaft (2), a stroke input gear (1), a base (3), and a photoelectric sensor code-fetching circuit and a level conversion circuit The control circuit is characterized in that the stroke input gear (1), the speed-up gear (5) and the speed-down gear (6) are fixed on the stroke input shaft (2), and the speed-up gear (5) and the motor The first layer of counting gears (29) at the rotor position are meshed, and the 1-4 bit code disc (22) and the first code fetching circuit (21) are fixed under the first layer of counting gears (29) at the rotor position; The gear meshed with the first layer of counting gear (29) at the rotor position drives the second layer of counting gear (27) at the rotor position to rotate, and the 5~8 positions are fixed under the second layer of counting gear (27) at the rotor position. The code disc (26) and the second code fetching circuit (24); the reduction gear (6) is meshed with the first bottom counting gear (28) of the valve position, on the first bottom counting gear (28) of the valve position Fix the 1st to 4th code disc (8) and the third code fetching circuit (9), and the gear meshed with the first bottom counting gear (28) of the valve position drives the second bottom counting gear (17) of the valve position to rotate; The 5th to 8th code disc (16) and the fourth code fetching circuit (20) are fixed on the second bottom counting gear (17) of the valve position, which are in phase with the second bottom counting gear (17) of the valve position The meshed second intermediate gear (15) drives the first top-level counting gear (11) to rotate, and is fixed under the first top-level counting gear (11) to connect the 9th to 12th bit code discs (10) and the fifth code fetching circuit (10 ), the first intermediate gear (14) meshing with the first top counting gear (11) drives the second top counting gear (18) to rotate, and is fixed under the second top counting gear (18) and then the 13th to 16th Bit code disc (19) and the sixth code fetching circuit (20). 2. An encoder integrating motor rotor position detection and valve position stroke detection according to claim 1, characterized in that the speed-up toothed plate (5) and the rotor position first layer counting gear (29) The total ratio of the teeth is 1:5; the total ratio of the teeth of the reduction gear (6) and the first bottom counting gear (28) of the valve position is 40:1. 3. An encoder integrating motor rotor position detection and valve position stroke detection according to claim 1 or 2, characterized in that a reflective photoelectric sensor is arranged under the code disc. 4 . The integrated encoder for motor rotor position detection and valve position stroke detection according to claim 3 , characterized in that the integrated encoder is a multi-turn absolute encoder and is encoded by Gray code.

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