JP4820328B2 - Rotation state detection device - Google Patents

Description

  The present invention relates to a rotation state detection device that detects the number of rotations and a rotation direction of a rotating body based on phase differences of detection signals from a plurality of sensors.

  In order to detect the rotating state of the rotating body, two sensors are arranged at predetermined intervals along the rotating direction of the rotating body, and the rotational speed and rotation of the rotating body are detected using the phase difference of detection signals from both sensors. A method for detecting a direction is known (see, for example, Patent Documents 1 and 2).

  For example, in a conventional method for detecting the rotation state of a rotating body, a gear made of a magnetic body and rotating in synchronization with the rotating body is used. A plurality of crests and troughs are alternately formed at predetermined intervals on the outer periphery of the gear.

  In order to detect the rotation state of the gear, a magnetic sensor composed of two sets of magnetoresistive elements is arranged opposite the gear and spaced at a predetermined interval along the rotation direction of the gear. Each of these two magnetic sensors outputs a binary detection signal (pulse signal) corresponding to the crest and trough of the gear according to the rotation of the gear.

  The case where the gear rotates clockwise is the forward rotation, and the reverse case is the reverse rotation. In the case of forward rotation, the detection output of one sensor precedes the phase of the detection output of the other sensor, and in the case of reverse rotation, the detection output of the other sensor precedes the phase of the detection output of one sensor. Is observed. The phase difference between the two sensor detection outputs can be adjusted by appropriately adjusting the distance between the crest and trough of the gear and the distance between both sensors. For example, the phase difference is adjusted so as to be a quarter cycle.

  Specifically, the detection outputs from the two sensors are input to a D flip-flop (hereinafter referred to as “DFF”) for detecting the rotation direction. More specifically, the detection output of one sensor (hereinafter referred to as “first sensor”) is the data input of the DFF, and the detection output of the other sensor (hereinafter referred to as “second sensor”) is the DFF. Connected to clock input.

  That is, the DFF observes the data input (detection output of the first sensor) at the rising edge of the clock input (detection output of the second sensor), and detects the rotation direction of the gear according to the polarity of the data input. That is, when the gear rotates in the forward direction, the first sensor detection output is always “High” at the time when the detection output of the second sensor rises, so that the DFF outputs “ “High” is output.

  On the other hand, when the gear rotates in the reverse direction, the first sensor detection output is always “Low” at the rising edge of the second sensor detection output. Therefore, the DFF outputs “Low” as the rotation direction detection result output indicating the reverse rotation. Output.

JP-A-10-332725 (

Fig. 1)
JP-A-10-122903

  When the conventional rotational state detection device as described above is used for an automobile engine or the like, high-level control is required, such as instantaneously detecting a change in rotational direction. In the above conventional rotation state detection device, the rotation direction is detected only when the output signal from the magnetic sensor rises. Therefore, depending on the timing at which the rotation direction is switched, the rotation state is switched to the actual rotation state. It may take a very long time to detect the switching of the.

  The delay in detecting the switching of the rotation state causes the following problems. For example, when a conventional rotational state detection device is used to detect the rotational speed and rotational position of an automobile engine, the automotive control device observes the detection output of the sensor, recognizes the rotational speed and rotational position of the engine, and The opening / closing timing and ignition timing of the plug are generated. In addition, an accurate rotational position can be recognized even when the engine rotates in reverse by using the rotational direction detection output from the sensor. For this reason, if the detection of the switching of the rotational direction is delayed, the accurate rotational position cannot be recognized, and various timings for engine control are shifted, and normal operation cannot be performed.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a rotating body detection device that can quickly detect the switching point of the rotating direction of the rotating body.

  The rotation state detection device of the present invention includes a first rotation direction detection means for observing the detection signal of the second sensor at the rising edge of the detection signal of the first sensor and detecting the rotation direction of the rotating body; From the detection result of the second rotation direction detection means for observing the detection signal of the second sensor at the fall of the detection signal of the sensor and detecting the rotation direction of the rotating body, and the first and second rotation direction detection means Rotation direction discriminating means for selecting and outputting the one with the earlier detection timing. Moreover, you may further provide the rotation speed detection means which outputs the signal which changes according to the rotation speed of a rotary body based on the detection signal of a 1st and 2nd sensor.

  According to the present invention, the rotation direction is detected at the rise and fall of the detection signal of the first sensor, and the detection result is quickly output by selecting the one with the earlier detection timing as the rotation direction discrimination result. be able to. Further, by switching the output level of the rotation speed output control means in accordance with the rotation direction discrimination result, both the rotation speed information and the rotation direction discrimination information can be transmitted with one signal line.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

Embodiment 1 FIG.
With reference to FIG. 1 to FIG. 7, a rotational state detection apparatus according to Embodiment 1 of the present invention will be described.

(Configuration of rotation state detection device)
FIG. 1 is a configuration diagram of Embodiment 1 of the rotational state detection device of the present invention. The rotation state detection device includes a gear 1 having crests 1a and troughs 1b alternately formed on the outer peripheral portion, sensors 21 and 22 disposed opposite to the gear 1, and detection outputs 21a from the sensors 21 and 22. , 22a, and a rotation direction determination unit 4a that receives detection results 22r and 22f from the rotation direction detection unit 3a.

  Each of the sensors 21 and 22 is a magnetic sensor, and is composed of, for example, two sets of magnetoresistive elements. The sensors 21 and 22 are arranged at a predetermined interval along the rotation direction of the gear 1 so as to face the gear 1 in order to detect the rotation state of the gear 1, respectively. A binary detection signal corresponding to the valley 1b is output.

  The rotation direction detection unit 3a outputs detection results 22r and 22f of the rotation direction at the rise / fall of the sensor detection output 22a. The rotation direction determination unit 4a selects the detection result output 22r, 22f of the rotation direction detection unit 3a with the earlier detection timing and outputs it as the rotation direction determination output det_a.

  FIG. 2 is a diagram illustrating an example of the configuration of the rotation direction detection unit 3a. The rotation direction detection unit 3a includes two DFFs (D flip-flop circuits) 31a and 32a. In the figure, a circle at the clock input of the DFF 32a indicates an inverting input, which means that the DFF 32a holds data at the falling edge of the clock.

  The DFF 31a inputs the sensor detection output 21a as a data input, inputs the detection output 22a from the sensor 22 as a clock input, and rotates the sensor detection output 21a (data input) when the sensor detection output 22a (clock input) rises. It outputs as direction detection result 22r.

  The DFF 32a inputs the sensor detection output 21a as a data input, inputs the inversion of the sensor detection output 22a as a clock input, and rotates the sensor detection output 21a (data input) when the sensor detection output 22a (clock input) falls. It outputs as direction detection result 22f. The output Qn means that an inverted signal of the observed data input is output.

  FIG. 3 is a diagram illustrating an example of the configuration of the rotation direction determination unit 4a. The rotational direction discriminating unit 4a receives the sensor detection output 22a and the rotational direction detection results 22r and 22f, selects the rotational timing detection result 22r and 22f input earlier, and determines the rotational direction. The result is output as det_a. In the figure, the circles at the inputs of the AND circuits 41a and 42a mean that the signals are inverted and input, and the circles at the outputs of the AND circuit 41a mean that the signals are inverted and output.

(Operation of the rotation state detection device)
The operation of the rotational state detection apparatus configured as described above will be described.

(Detection operation during forward rotation)
First, the operation of the rotation state detection device when the gear 1 is rotating forward will be described. FIG. 4 is a diagram showing the timing of signals of each part of the rotation state detection device when the gear 1 is rotating forward. The DFF 31a observes the sensor detection output 21a at times t1, t3, and t5 when the sensor detection output 22a rises. Referring to FIG. 4, since the sensor detection output 21a is always “High” at times t1, t3, and t5, the detection result 22r is always “High”.

  The DFF 32a of the rotation direction detector 3a observes the sensor detection output 21a at times t2, t4, and t6 when the sensor detection output 22a falls. Referring to FIG. 4, since the sensor detection output 21a is always “Low” at times t2, t4, and t6, the detection result 22f is always “High” which is an inversion thereof.

  In the rotation direction discriminating unit 4a, the rotation direction detection result 22f is always “High”, so that the output of the AND circuit 41a is always “High”. Further, since the rotation direction detection result 22r is always “High”, the output of the OR circuit 47a is always “High”. Therefore, since the output of the AND circuit 41a is always “High” and the output of the OR circuit 47a is always “High”, the output of the AND circuit 48a, that is, the output det_a of the rotation direction discriminating unit 4a is always “High”. That is, in the case of forward rotation, the output det_a of the rotation direction determination unit 4a is “High”.

(Detection operation during reverse rotation)
Next, the operation of the rotation state detection device when the gear 1 is rotating in the reverse direction will be described with reference to FIG. FIG. 5 is a diagram illustrating the timing of signals of each part of the rotation state detection device when the gear 1 is rotating in the reverse direction.

  The DFF 31a of the rotation direction detector 3a observes the sensor detection output 21a at times t7, t9, and t13 when the sensor detection output 22a rises. At these timings, the sensor detection output 21a is always “Low” as shown in FIG. 5, so that the detection result 22r is always “Low” as shown in FIG.

  The DFF 32a observes the sensor detection output 21a at times t8, t12, and t14 when the sensor detection output 22a falls. Since the sensor detection output 22a is always “High” at these timings as shown in FIG. 5, the detection result 22f is always “Low” which is the inversion thereof.

  Since the rotation direction detection result 22r is always “Low”, the output of the AND circuit 41a is always “High” in the rotation direction determination unit 4a. Since the rotation direction detection result 22f is always “Low”, the output of the AND circuit 42a is always “Low”. That is, since both the rotation direction detection result 22r and the output of the AND circuit 42a are always “Low”, the output of the OR circuit 47a is always “Low”. Accordingly, both the output of the AND circuit 41a and the output of the OR circuit 47a are always “Low”, so the output of the AND circuit 48a, that is, the output det_a of the rotation direction discriminating unit 4a is always “Low”. That is, in the case of reverse rotation, the output det_a of the rotation direction determination unit 4a is “Low”.

(Detection of switching from forward rotation to reverse rotation)
Next, the operation of the rotation state detection apparatus when the rotation direction is switched from forward rotation to reverse rotation will be described. Hereinafter, an example in which the rotation direction of the gear 1 is switched from the forward rotation to the reverse rotation during the period in which the sensor detection output 21a is “Low” and the sensor detection output 22a is “High” will be described with reference to FIG. To do. FIG. 6 shows the timing of signals at various parts of the rotation state detection device when the rotation direction of the gear 1 is switched from the normal rotation to the reverse rotation during the period when the sensor detection output 21a is “Low” and the sensor detection output 22a is “High”. FIG.

  In the rotation direction detection unit 3a, the DFF 31a detects the rotation direction when the sensor detection output 22a rises. Therefore, the rotation direction is detected at time t16, and the detection result 22r is output.

  Since the DFF 32a detects the rotation direction when the sensor detection output 22a falls, the DFF 32a detects that the rotation direction has been switched at time t15, and outputs a detection result 22f.

  In the rotation direction determination unit 4a, the rotation direction detection result 22r changes from “High” to “Low” at time t16, and the rotation direction detection result 22f changes from “High” to “Low” at time t15. Therefore, in the period between time t15 and time t16, (sensor detection output 22a, rotation direction detection result 22r, rotation direction detection result 22f) = (“Low”, “High”, “Low”), and therefore, the AND circuit 41a. Outputs “Low” during the period from time t15 to time t16.

  On the other hand, while the rotation direction detection result 22r is “Low”, the rotation direction detection result 22f does not become “High”, so (sensor detection output 22a, rotation direction detection result 22r, rotation direction detection result 22f) = (“Low”. "," Low "," High "), and the output of the AND circuit 42a is always" Low ".

  Since the rotation direction detection result 22r changes from “High” to “Low” at time t16 and the output of the AND circuit 42a is always “Low”, the output of the OR circuit 47a is changed from “High” to “Low” at time t16. To change.

  The output of the AND circuit 41a is “Low” from time t15 to time t16, and the output of the OR circuit 47a changes from “High” to “Low” at time t16. The output det_a of the unit 4a is a signal that changes from “High” to “Low” at time t15. That is, of the rotation direction detection results 22r and 22f, the rotation direction detection result 22f detected at time t15 and detected earlier is selected and output.

  Thus, in the above example, the rotation direction detection result 22f at the time of falling, which is the earlier of the rotation direction detection result 22r at the time of rising of the sensor detection output 22a and the rotation direction detection result 22f at the time of falling. Is output as the rotation direction discrimination result det_a, so that the switching of the rotation direction can be detected earlier than using only the rotation direction detection result at the time of rising of the sensor detection output 22a of the prior art.

(Detection of switching from reverse rotation to forward rotation)
Next, the operation of the rotation state detection device when the rotation direction is switched from reverse rotation to normal rotation will be described. Hereinafter, an example in which the rotation direction of the gear 1 is switched from the reverse rotation to the normal rotation during the period in which both the sensor detection output 21a and the sensor detection output 22a are “High” will be described with reference to FIG. FIG. 7 is a diagram showing the timing of signals at various parts of the rotation state detection device when the rotation direction of the gear 1 is switched from reverse rotation to normal rotation during a period when both the sensor detection output 21a and the sensor detection output 22a are “High”. is there.

  In the rotation direction detection unit 3a, the DFF 31a detects the rotation direction when the sensor detection output 22a rises. Therefore, it detects that the rotation direction has been switched at time t18, and outputs a detection result 22r.

  Since the DFF 32a detects the rotation direction when the sensor detection output 22a falls, the DFF 32a detects that the rotation direction has been switched at time t17, and outputs a detection result 22f.

  While the rotation direction detection result 22f is “Low”, the rotation direction detection result 22r does not become “High”. Therefore, in the rotation direction determination unit 4a, (sensor detection output 22a, detection result 22r, detection result 22f) = (“ Low ”,“ High ”,“ Low ”), and the output of the AND circuit 41a is always“ High ”.

  On the other hand, since (sensor detection output 22a, detection result 22r, detection result 22f) = (“Low”, “Low”, “High”) is established in the period between times t17 and t18, the AND circuit 42a During the period from t17 to time t18, “High” is output.

  Since the rotation direction detection result 22r changes from “Low” to “High” at time t18, and the output of the AND circuit 42a is “High” from time t17 to time t18, the output of the OR circuit 47a is It changes from “Low” to “High” at t17.

  Since the output of the AND circuit 41a is always “High” and the output of the OR circuit 47a changes from “Low” to “High” at time t17, the output of the AND circuit 48a, that is, the output det_a of the rotation direction determination unit 4a is At time t17, the signal changes from “Low” to “High”. That is, among the rotation direction detection results 22r and 22f, the rotation direction detection result 22f with the earlier detection timing is selected and output.

(effect)
As described above, in the first embodiment of the present invention, the faster one of the rotation direction detection result 22r when the sensor detection output 22a rises and the rotation direction detection result 22f when the sensor detection output 22a falls (rotates at the timing shown in FIG. 6). When the direction is switched, the rotation direction detection result 22f at the fall) is output as the rotation direction discrimination result det_a. Therefore, the rotation is performed rather than using only the rotation direction detection result at the rise of the sensor detection output 22a of the conventional example. The change of direction can be detected quickly.

Embodiment 2. FIG.
A second embodiment of the rotational state detection device of the present invention will be described with reference to FIGS.

  FIG. 8 is a configuration diagram of the rotational state detection device according to the second embodiment of the present invention. The rotation state detection device of the present embodiment further includes a rotation speed output control unit 5a in addition to the configuration of the rotation state detection device shown in FIG. The rotation speed output control unit 5a switches the output level of the sensor detection output 22a in accordance with the rotation direction determination result det_a, thereby superimposing the information on the rotation direction determination result det_a on the sensor detection output 22a and rotating the rotation speed output out_a. Is output.

  FIG. 9 shows an example of the configuration of the rotation speed output control unit 5a. FIG. 9 shows a circuit example when the “Low” level of the output signal is switched depending on the rotation direction. The AND circuits 51a and 52a turn on / off the switches of the transistor circuits 54a and 55a. When the rotation direction discrimination result det_a is “High”, the AND circuit 51a outputs “High” when the sensor detection output 22a is “Low”. When the rotation direction determination result det_a is “Low”, the AND circuit 52a outputs “High” when the sensor detection output 22a is “Low”. The transistor circuit 54a is turned on when the output of the AND circuit 51a is "High". The transistor circuit 55a is turned on when the AND circuit 52a is “High”.

Hereinafter, the operation of the rotation state detection device of the present embodiment will be described with reference to FIG. While the gear 1 is rotating forward, the rotation direction determination result det_a is “High”, so that the output of the AND circuit 52a is “Low”, and the transistor circuit 55a is always off. In this case, when the sensor detection output 22a is “High”, the output of the AND circuit 51a is “Low”, the transistor circuit 54a is also turned off, and the voltage of the rotation speed output out_a becomes the same voltage VH0 as Vcc. On the other hand, when the sensor detection output 22a is “Low”, the output of the AND circuit 51a is “High”, the transistor circuit 54a is turned on, and the point A is at the same level as GND. Therefore, the voltage VL0 of the rotation speed output out_a is It is given by

When the gear 1 rotates in the reverse direction, the rotation direction determination result det_a becomes “Low”, so that the output of the AND circuit 51a becomes “Low” and the transistor circuit 54a is always off. In this case, when the sensor detection output 22a is “High”, the output of the AND circuit 52a is “Low”, the transistor circuit 55a is also turned off, and the voltage of the rotation speed output out_a becomes the same voltage VH0 as Vcc. On the other hand, when the sensor detection output 22a is “Low”, the output of the AND circuit 52a becomes “High”, the transistor circuit 55a is turned on, the point A is connected to GND through the resistor R2, and the rotation speed output out_a The voltage VL1 is given by the following equation.

  Here, for example, if Vcc = 5V, R0 = 10 kilohm, R1 = 1 kiloohm, and R2 = 6 kiloohm, the respective output voltages are about VH0 = 5V, VL0 = 0.5V, and VL1 = 2V. Therefore, in the subsequent signal processing circuit that receives the rotational speed output signal out_a, for example, as shown in FIG. 10, by setting the threshold voltage Vth0 for rotational speed detection to about 2.5 V, the gear 1 Rotational speed can be measured. For example, the number of rotations can be recognized by measuring the number of pulses exceeding the threshold voltage Vth0. Furthermore, the rotation direction of the gear 1 can be observed by setting the threshold voltage Vth1 for detecting the rotation direction to about 1.5V. For example, the rotation direction can be detected by observing whether the value of the rotation speed output signal out_a is lower than the threshold voltage Vth1.

  In the second embodiment, the example in which the sensor detection output 22a is used for the output of the rotational speed has been described, but the sensor detection output 21a may be used for the output of the rotational speed.

  According to the rotation state detection device of the present embodiment, the rotation direction change can be detected quickly, and information indicating the rotation direction as well as the rotation number can be included in one signal out_a and output. There is no need to provide a signal line for each piece of rotation direction detection information.

Embodiment 3 FIG.
Embodiment 3 of the rotational state detection device of the present invention will be described with reference to FIGS. 11 and 12.

  FIG. 11 is a diagram showing another configuration example of the rotation speed output control unit 5a in the second embodiment. The circuit example in the case of switching the "High" level of an output signal with the rotation direction is shown. The NOT circuit 51b turns on / off the switch of the transistor circuit 54a. The AND circuit 53b turns on / off the switch of the transistor circuit 56a. The NOT circuit 51b outputs “High” when the sensor detection output 22a is “Low”. On the other hand, when the rotation direction determination result det_a is “Low”, the AND circuit 53b outputs “High” when the sensor detection output 22a is “High”. The transistor circuit 54a is turned on when the output of the NOT circuit 51b is “High”. The transistor circuit 56a is turned on when the output of the AND circuit 53b is “High”.

  Hereinafter, the operation of the rotation speed output control unit 5a in the present embodiment will be described with reference to FIG.

While the gear 1 is rotating forward, the rotation direction determination result det_a is “High”, so that the AND circuit 53b is “Low” and the transistor circuit 56a is turned off. When the sensor detection output 22a is “High”, the output of the NOT circuit 51b is “Low”, the transistor circuit 54a is also turned off, and the voltage of the rotation speed output out_a becomes the same voltage VH0 as Vcc. When the sensor detection output 22a is “Low”, the NOT circuit 51b is “High”, the transistor circuit 54a is turned on, and the point A is at the same level as GND. Therefore, the voltage VL0 of the rotation speed output out_a is given by the following equation. It is done.

During the reverse rotation of the gear 1, when the sensor detection output 22a is "Low", the AND circuit 53b is "Low" and the transistor circuit 56a is turned off. Further, at that time, the NOT circuit 51b becomes “High”, the transistor circuit 54a is turned on, the point A becomes the same level as GND, and the voltage of the rotation speed output out_a becomes VL0 as in the normal rotation. When the sensor detection output 22a is “High”, the NOT circuit 51b is “Low” and the transistor circuit 54a is turned off. At that time, the AND circuit 53b becomes “High”, the transistor circuit 56a is turned on, the point A is connected to GND through the resistor R3, and the voltage VH1 of the rotation speed output out_a is given by the following equation.

  For example, if Vcc = 5V, R0 = 10 kilohm, R1 = 1 kiloohm, and R3 = 14 kiloohm, the respective output voltages are about VH0 = 5V, VL0 = 0.5V, and VH1 = 3V. Accordingly, in the subsequent signal processing circuit that receives the signal of the rotational speed output out_a, for example, as shown in FIG. 12, by setting the value of the threshold voltage Vth0 for rotational speed measurement to about 2.5 V, the gear 1 Can be measured. Furthermore, the rotational direction of the gear 1 can also be observed by setting the threshold voltage Vth1 for detecting the rotational direction to about 4V.

  In the third embodiment, the example in which the sensor detection output 22a is used for the rotation speed output has been described. However, the sensor detection output 21a may be used for the rotation speed output.

Embodiment 4 FIG.
Embodiment 4 of the rotational state detection device of the present invention will be described with reference to FIGS. 13 and 14.

  FIG. 13 is a diagram showing still another configuration example of the rotation speed output control unit 5a in the rotation state detection device of the second embodiment. FIG. 13 shows a circuit example when the output signal is switched between “High” level and “Low” level depending on the rotation direction.

  The AND circuits 51c, 52c, and 53c turn on / off the switches of the transistor circuits 54a, 55a, and 56a, respectively. The AND circuit 51c outputs “High” when the sensor detection output 22a is “Low” when the rotation direction determination result det_a is “High”. The AND circuit 52c outputs “High” when the sensor detection output 22a is “Low” when the rotation direction determination result det_a is “Low”. When the rotation direction determination result det_a is “Low”, the AND circuit 53c outputs “High” when the sensor detection output 22a is “High”. The transistor circuits 54a, 55a and 56a are turned on when the outputs of the AND circuits 51c, 52c and 53c are “High”, respectively.

  Hereinafter, the operation of the rotation speed output control unit 5a of the present embodiment will be described with reference to FIG.

While the gear 1 is rotating forward, the rotation direction discrimination result det_a is “High”, so that the AND circuits 52c and 53c are “Low” and the transistor circuits 55a and 56a are turned off. When the sensor detection output 22a is “High”, the AND circuit 51c becomes “Low”, the transistor circuit 54a is also turned off, and the voltage of the rotation speed output out_a becomes the same voltage VH0 as Vcc. When the sensor detection output 22a is “Low”, the AND circuit 51c is “High”, the transistor circuit 54a is turned on, and the point A is at the same level as GND. Therefore, the voltage VL0 of the rotation speed output out_a is given by the following equation. It is done.

When the gear 1 rotates in the reverse direction, the rotation direction determination result det_a is “Low”, so that the AND circuit 51c is “Low” and the transistor circuit 54a is always off. When the sensor detection output 22a is “Low”, the AND circuit 52c becomes “High”, and the transistor circuit 55a is turned on. At the same time, the AND circuit 53c becomes “Low” and the transistor circuit 56a is turned off. The voltage VL1 of the rotation speed output out_a is given by the following equation.

When the sensor detection output 22a is “High”, the AND circuit 52c is “Low”, the transistor circuit 55a is turned off, and simultaneously, the AND circuit 53c is “High”, the transistor circuit 56a is turned on, and the point A is connected to the resistor R3. The voltage VH1 of the rotation speed output out_a is given by the following equation.

  Here, for example, if Vcc = 5V, R0 = 10 kilohm, R1 = 1 kiloohm, R2 = 6 kiloohm, R3 = 14 kiloohm, the respective output voltages are VH0 = 5V, VL0 = 0.5V, VH1 = 3V, VL1 = 2V or so. Accordingly, in the subsequent signal processing circuit that receives the signal of the rotational speed output out_a, for example, as shown in FIG. 14, a threshold value Vth0 for rotational speed measurement is provided, and the value is set to about 2.5V. The rotation speed of the gear 1 can be measured. Furthermore, by providing threshold values Vth1 and Vth2 for detecting the rotation direction and setting them to about 4V and about 1.5V, respectively, the rotation direction of the gear 1 can also be observed. For example, the rotational direction can be detected by observing whether or not the value of the rotational speed output out_a falls within the range between the threshold value Vth1 and the threshold value Vth2.

  In the fourth embodiment, the example in which the sensor detection output 22a is used for the output of the rotational speed has been described. However, the sensor detection output 21a may be used for the output of the rotational speed.

Embodiment 5 FIG.
Embodiment 5 of the rotational state detection device of the present invention will be described with reference to FIGS. 15 and 16.

  FIG. 15 is a diagram showing still another configuration example of the rotation speed output control unit 5a in the rotation state detection device of the second embodiment. FIG. 15 shows an example of a circuit that stops output when the rotation direction is reverse rotation. The AND circuit 51d outputs the sensor detection output 22a only when the rotation direction determination result det_a is “High”, and always outputs “High” when the rotation direction determination result det_a is “Low”.

  Hereinafter, the operation of the rotation speed output control unit 5a of the present embodiment will be described with reference to FIG. Since the rotation direction discrimination result det_a is “High” while the gear 1 is rotating forward, the AND circuit 51d, that is, the rotation speed output out_a outputs “Low” when the sensor detection output 22a is “Low”. When the sensor detection output 22a is "High", "High" is output. On the other hand, since the rotation direction determination result det_a is “Low” while the gear 1 is rotating in the reverse direction, the output of the AND circuit 51d, that is, the rotation speed output out_a always outputs “High”.

  Accordingly, the rotation speed output control unit 5a outputs a pulse signal corresponding to the sensor detection output 22a while the gear 1 is rotating forward, and masks the pulse signal while the gear 1 is rotating in the reverse direction. Fix to “High”.

  In this way, for example, in a system that counts this pulse signal and recognizes the rotational position of the rotating body, if the normal rotation is normal and the reverse rotation is abnormal, the pulse signal is masked at the time of abnormality. Therefore, it is possible to avoid erroneous counting of the number of rotations. On the other hand, if the device is normal in normal rotation and normal in reverse rotation, a pulse signal is output if the rotation direction becomes abnormal, so that the device abnormality can be detected.

  In the above description, an example is shown in which the pulse signal is masked and fixed to “High” during reverse rotation, but may be fixed to “Low”. The signal may be masked and fixed to “High” or “Low”. Moreover, although the example which used the sensor detection output 22a for the output of rotation speed was demonstrated, you may use the sensor detection output 21a for the output of rotation speed.

Embodiment 6 FIG.
Embodiment 6 of the rotational state detection device of the present invention will be described with reference to FIGS.

(Configuration of rotation state detection device)
The rotation state detection device according to the present embodiment is different from the rotation state detection device according to the first embodiment in the configuration of the rotation direction detection unit and the rotation direction determination unit. The rotation direction detection unit 3b outputs rotation direction detection results 21r, 21f, 22r, and 22f when the sensor detection outputs 21a and 22a rise and fall, respectively. The rotation direction determination unit 4b selects the detection result output 21r, 21f, 22r, 22f of the rotation direction detection unit 3b with the earliest detection timing and outputs it as the rotation direction determination output det_b.

  FIG. 18 shows an example of the configuration of the rotation direction detection unit 3b shown in FIG. The rotation direction detection unit 3b includes four DFFs 31b, 32b, 33b, and 34b. In the drawing, the clock input circles of the DFFs 32b and 34b indicate inverted inputs, which means that the data at the falling edge of the clock are held, respectively, and the output Qn indicates that the observed data input is inverted. means.

  The DFF 31b inputs the sensor detection output 21a to the data input, inputs the sensor detection output 22a to the clock input, and outputs the rotation direction detection result 22r when the sensor detection output 22a rises.

  The DFF 32b inputs the sensor detection output 21a to the data input, inputs the inversion of the sensor detection output 22a to the clock input, and outputs the rotation direction detection result 22f when the sensor detection output 22a falls.

  The DFF 33b inputs the sensor detection output 22a to the data input, inputs the sensor detection output 21a to the clock input, and outputs the rotation direction detection result 21r when the sensor detection output 21a rises.

  The DFF 34b inputs the sensor detection output 22a to the data input, inputs the inversion of the sensor detection output 21a to the clock input, and outputs the rotation direction detection result 21f when the sensor detection output 21a falls.

  FIG. 19 is a diagram illustrating an example of the configuration of the rotation direction determination unit 4b illustrated in FIG. The rotation direction discriminating unit 4b receives the sensor detection outputs 21a and 22a and the rotation direction detection results 21r, 21f, 22r, and 22f and has the earliest detection timing among the rotation direction detection results 21r, 21f, 22r, and 22f. Is output as the rotation direction discrimination result det_b. In the figure, the circles at the input parts of the AND circuits 41b to 46b mean that the signals are inverted and input, and the circles at the output parts of the AND circuits 41b, 45b, and 46b are the signals that are inverted. It means to do.

(Operation of the rotation state detection device)
Hereinafter, the operation of the rotational state detection device of the present embodiment will be described with reference to FIGS.

(Detection operation during forward rotation)
The operation of the rotation state detection device when the gear 1 is rotating forward will be described. FIG. 20 shows the timing of each signal when the gear 1 is rotating forward. The DFF 31b observes the sensor detection output 21a at times t20, t24, and t28 when the sensor detection output 22a rises. At that timing, since the sensor detection output 21a is always “High”, the detection result 22r is always “High”.

  The DFF 32b observes the sensor detection output 21a at times t22, t26, and t30 when the sensor detection output 22a falls. At that timing, since the sensor detection output 21a is always “Low”, the detection result 22f is always “High” which is the inversion thereof.

  The DFF 33b observes the sensor detection output 22a at times t19, t23, and t27 when the sensor detection output 21a rises. At that timing, since the sensor detection output 22a is always “Low”, the detection result 21r is always “High” which is the inversion thereof.

  The DFF 34b observes the sensor detection output 22a at times t21, t25, and t29 when the sensor detection output 21a falls. At that timing, since the sensor detection output 22a is always “High”, the detection result 21f is always “High”.

  Since the detection result output 22r is always “High” while the gear 1 is rotating forward, the output of the OR circuit 47b is always “High” in the rotation direction discriminating unit 4b.

  At this time, since the detection result output 22f is always “High”, the output of the AND circuit 41b is always “High”. Since the detection result output 21r is always “High”, the output of the AND circuit 45b is always “High”. Since the detection result output 21f is always “High”, the output of the AND circuit 46b is also always “High”. Therefore, while the gear 1 is rotating forward, the output of the AND circuit 48b, that is, the rotation direction determination output det_b is always “High”.

(Detection operation during reverse rotation)
Next, the operation when the gear 1 is rotating in the reverse direction will be described with reference to FIG. The DFF 31b observes the sensor detection output 21a at times t31, t35, and t39 when the sensor detection output 22a rises. At that timing, since the sensor detection output 21a is always “Low”, the detection result 22r is always “Low”.

  The DFF 32b observes the sensor detection output 21a at times t33, t37, and t41 when the sensor detection output 22a falls. At that timing, since the sensor detection output 21a is always “High”, the detection result 22f is always “Low” which is the inversion thereof.

  The DFF 33b observes the sensor detection output 22a at times t32, t36, and t40 when the sensor detection output 21a rises. At that timing, since the sensor detection output 22a is always “High”, the detection result 21r is always “Low” which is the inversion thereof.

  The DFF 34b observes the sensor detection output 22a at times t34, t38, and t42 when the sensor detection output 21a falls. At that timing, since the sensor detection output 22a is always “Low”, the detection result 21f is always “Low”.

  While the gear 1 is rotating in the reverse direction, the rotation direction detection result 22f is always “Low”, so the output of the AND circuit 42b is always “Low”. Similarly, since the rotation direction detection result 21f is always “Low”, the AND circuit 43b is always “Low”. Further, since the rotation direction detection result 21r is always “Low”, the AND circuit 44b is always “Low”. Therefore, while the gear 1 is rotating in the reverse direction, the output of the OR circuit 47b is always “Low”, so the output of the AND circuit 48b, that is, the rotation direction determination output det_b always outputs “Low”.

  As described above, when the rotation direction of the gear 1 is forward rotation or reverse rotation, the rotation direction determination unit 4b outputs “High” and “Low” indicating the forward rotation and the reverse rotation, respectively, as the rotation direction determination result det_b. To do.

(Detection of switching from forward rotation to reverse rotation)
Next, the operation when the rotation direction is switched from forward rotation to reverse rotation will be described with reference to FIG. That is, in the following, an example will be described in which the rotation direction is switched during a period in which the sensor detection output 21a is “Low” and the sensor detection output 22a is “High”.

  Since the DFF 31b detects the rotation direction when the sensor detection output 22a rises, the DFF 31b detects that the rotation direction has been switched at time t46, and outputs a detection result 22r.

  Since the DFF 32b detects the rotation direction when the sensor detection output 22a falls, the DFF 32b detects that the rotation direction has been switched at time t44, and outputs a detection result 22f.

  Since the DFF 33b detects the rotation direction when the sensor detection output 21a rises, the DFF 33b detects that the rotation direction has been switched at time t43, and outputs a detection result 21r.

  Since the DFF 34b detects the rotation direction when the sensor detection output 21a falls, the DFF 34b detects that the rotation direction has been switched at time t45, and outputs a detection result 21f.

  In the rotation direction discriminating unit 4b, the rotation direction detection result 22f changes from “High” to “Low” at time t44, and the rotation direction detection result 22r changes from “High” to “Low” at time t46. Since the sensor detection output 22a is “Low” during t46, the output of the AND circuit 41b is “Low” from time t44 to t46.

  Since the rotation direction detection result 22r is also “High” while the rotation direction detection result 22f is “High”, (sensor detection output 22a, detection result 22r, detection result 22f) = (“Low”, “Low”, “ Since the relationship of “High”) is not established, the output of the AND circuit 42b is always “Low”.

  On the other hand, during the time t43 to t45, the rotation direction detection result 21r is “Low” and the rotation direction detection result 21f is “High”. During this period, the sensor detection output 21a is “High” (sensor detection output 21a , Detection result 21r, detection result 21f) = (“Low”, “Low”, “High”) does not hold, the output of the AND circuit 43b is always “Low”.

  Since the rotation direction detection result 21r is also “Low” while the rotation direction detection result 21f is “Low”, (sensor detection output 21a, detection result 21r, detection result 21f) = (“High”, “High”, “ Since “Low”) is not established, the output of the AND circuit 44b is always “Low”.

  Since (sensor detection output 21a, detection result 21r, detection result 21f) = (“High”, “Low”, “High”) is established from time t43 to t45, the AND circuit 45b is between time t43 and t45. , “Low” is output.

  Since the rotation direction detection result 21r is also “Low” while the rotation direction detection result 21f is “Low”, (sensor detection output 21a, detection result 21r, detection result 21f) = (“Low”, “High”, “ Low ") is not established, and the output of the AND circuit 46b is always" High ".

  The rotation direction detection result 22r changes from “High” to “Low” at time t46, and the outputs of the AND circuits 42b, 43b, and 44b are always “Low”. Therefore, the output of the OR circuit 47b is “High” at time t46. Changes from “Low” to “Low”.

  The output of the OR circuit 47b changes from “High” to “Low” at time t46, but the AND circuit 45b outputs “Low” from time t43 to t45, and the AND circuit from time t44 to t46. Since 41b outputs "Low", the output of the AND circuit 48b, that is, the output det_b of the rotation direction discriminating unit 4b becomes a signal that changes from "High" to "Low" at time t43.

  As described above, according to the present embodiment, it is possible to detect the change of the rotation direction at the timing of time t43. On the other hand, according to the prior art, the switching of the rotation direction is detected at the timing corresponding to the time t46 when the sensor detection output 21a becomes “Low” when the sensor detection output 22a rises for the first time after the switching occurs. Therefore, according to the present embodiment, it is possible to shorten the time required from the time when the actual rotation direction is changed to the time when the change is detected.

(Detection of switching from reverse rotation to forward rotation)
The operation when the rotation direction is switched from reverse rotation to forward rotation will be described with reference to FIG. That is, in the following, a case will be described as an example where the rotation direction is switched during a period when both the sensor detection output 21a and the sensor detection output 22a are “High”.

  Since the DFF 31b detects the rotation direction when the sensor detection output 22a rises, the DFF 31b detects that the rotation direction has been switched at time t50, and outputs a detection result 22r.

  Since the DFF 32b detects the rotation direction when the sensor detection output 22a falls, the DFF 32b detects that the rotation direction has been switched at time t48, and outputs a detection result 22f.

  Since the DFF 33b detects the rotation direction when the sensor detection output 21a rises, the DFF 33b detects that the rotation direction has been switched at time t49, and outputs a detection result 21r.

  Since the DFF 34b detects the rotation direction when the sensor detection output 21a falls, the DFF 34b detects that the rotation direction has been switched at time t47, and outputs a detection result 21f.

  Since the rotation direction detection result 22f is also “High” while the rotation direction detection result 22r is “High”, the rotation direction determination unit 4b (sensor detection output 22a, detection result 22r, detection result 22f) = (“ Low ”,“ High ”,“ Low ”) is not established, and the output of the AND circuit 41b is always“ High ”.

  The rotation direction detection result 22f changes from “Low” to “High” at time t48, and the rotation direction detection result 22r changes from “Low” to “High” at time t50. Since the sensor detection output 22a is “Low” from time t48 to t50, the AND circuit 42b is “High” from time t48 to t50.

  The rotation direction detection result 21f changes from “Low” to “High” at time t47, and the rotation direction detection result 21r changes from “Low” to “High” at time t49. Since the sensor detection output 21a is “Low” from time t47 to t49, the AND circuit 43b is “High” from time t47 to t49.

  On the other hand, since the rotation direction detection result 21r is also “Low” while the rotation direction detection result 21f is “Low”, (sensor detection output 21a, detection result 21r, detection result 21f) = (“High”, “High” , “Low”) does not hold, the output of the AND circuit 44b is always “Low”.

  From time t47 to t49, the rotation direction detection result 21r is “Low” and the rotation direction detection result 21f is “High”. During this time, the sensor detection output 21a is “Low” (sensor detection output 21a, detection Since the result 21r, the detection result 21f) = (“High”, “Low”, “High”) does not hold, the output of the AND circuit 45b is always “High”.

  Since the rotation direction detection result 21r is also “Low” while the rotation direction detection result 21f is “Low”, (sensor detection output 21a, detection result 21r, detection result 21f) = (“Low”, “High”, “ Low ") is not established, and the output of the AND circuit 46b is always" High ".

  The rotation direction detection result 22r changes from “Low” to “High” at time t50, the output of the AND circuit 42b becomes “High” from time t48 to t50, and the AND circuit 43b “High” from time t47 to t49. Since the output of the AND circuit 44b is always “Low”, the output of the OR circuit 47b changes from “Low” to “High” at time t47.

  The output of the OR circuit 47b changes from “Low” to “High” at time t47, but the AND circuits 41b, 45b, and 46b always output “High” from time t43 to t45, so the output of the AND circuit 48b. That is, the output det_b of the rotation direction determination unit 4b is a signal that changes from “Low” to “High” at time t47.

(Summary)
As described above, according to the present embodiment, it is possible to detect the change of the rotation direction at the timing of time t47. On the other hand, according to the prior art, the switching of the rotation direction is detected at a timing corresponding to time t50 when the sensor detection output 21a becomes “Low” when the sensor detection output 22a rises for the first time after the switching occurs. Therefore, according to the present embodiment, it is possible to shorten the time required from the time when the actual rotation direction is changed to the time when the change is detected.

Embodiment 7 FIG.
Embodiment 7 of the rotational state detection device of the present invention will be described with reference to FIGS.

  The rotation state detection device of the present embodiment shown in FIG. 24 further includes a rotation speed output control unit 5b in addition to the configuration of the sixth embodiment shown in FIG. The rotation speed output control unit 5b switches the output level of the sensor detection output 22a in accordance with the rotation direction determination result det_b, so that the rotation speed output obtained by superimposing the information on the rotation direction determination result det_b on the sensor detection output 22a. out_b is output.

  The configuration of the rotation speed output control unit 5b of the present embodiment has the same configuration as that shown in FIG. 9 in the second embodiment, inputs the rotation direction discrimination result det_b, and outputs the rotation speed output out_b.

  The operation of the rotation speed output control unit 5b of the present embodiment is basically the same as that of the second embodiment. However, when the rotation direction is switched from the normal rotation to the reverse rotation at the timing shown in FIG. 25, the subsequent signal processing circuit that receives the signal of the rotation speed output out_b observes the switching of the rotation direction at time t51. Can do.

  In the seventh embodiment, the example in which the sensor detection output 22a is used for the rotation speed output has been described. However, the sensor detection output 21a may be used for the rotation speed output.

Embodiment 8 FIG.
Embodiment 8 of the rotational state detection device of the present invention will be described with reference to FIG.
The rotation state detection device according to the eighth embodiment has basically the same configuration as that shown in FIG. 24 in the seventh embodiment except for the internal configuration of the rotation speed output control unit. The rotation speed output control unit 5b of the present embodiment has the same configuration as that of the rotation speed output control unit 5a shown in FIG.

  The operation of the rotation speed output control unit 5b of the present embodiment is the same as that of the third embodiment. However, when the rotation direction is switched from the normal rotation to the reverse rotation at the timing shown in FIG. 26, the subsequent signal processing circuit that receives the signal of the rotation speed output out_b observes the switching of the rotation direction at time t52. be able to.

  In this embodiment, the example in which the sensor detection output 22a is used for the output of the rotational speed has been described. However, the sensor detection output 21a may be used for the output of the rotational speed.

Embodiment 9 FIG.
Embodiment 9 of the rotational state detection device of the present invention will be described with reference to FIG.
The configuration of the rotation state detection device of the present embodiment has the same configuration as the configuration shown in FIG. 24 in Embodiment 7 except for the internal configuration of the rotation speed output control unit. The rotation speed output control unit 5b of the present embodiment has the same configuration as that of the rotation speed output control unit 5a shown in FIG.

  The operation of the rotation speed output control unit 5b of the present embodiment is the same as that of the fourth embodiment. However, when the rotation direction is switched from the normal rotation to the reverse rotation at the timing shown in FIG. 27, the subsequent signal processing circuit that receives the signal of the rotation speed output out_b observes the change of the rotation direction at time t53. be able to.

  In this embodiment, the example in which the sensor detection output 22a is used for the output of the rotational speed has been described. However, the sensor detection output 21a may be used for the output of the rotational speed.

Embodiment 10 FIG.
A tenth embodiment of the rotational state detection device of the present invention will be described with reference to FIG.
The rotational state detection device according to the present embodiment has the same configuration as the rotational state detection device according to the seventh embodiment except for the internal configuration of the rotational speed output control unit. The rotation speed output control unit 5b of the present embodiment has a configuration similar to that of the rotation speed output control unit 5a in the fifth embodiment.

  The operation of the rotation speed output control unit 5a in the fifth embodiment is the same as that in the fifth embodiment. However, when the rotation direction is switched from the normal rotation to the reverse rotation at the timing shown in FIG. 28, the rotation speed output out_b is always “High” during the reverse rotation.

  Therefore, while the gear 1 is rotating forward, the rotation speed output out_b outputs a pulse signal equivalent to the sensor detection output 22a. During the reverse rotation, the pulse signal is masked and becomes “High”. Fix it.

  In this way, for example, in a system that counts this pulse signal and recognizes the rotational position of the rotating body, if the normal rotation is normal and the reverse rotation is abnormal, the pulse signal is masked at the time of abnormality. Therefore, it is possible to avoid erroneous counting of the number of rotations. On the other hand, if the device is normal in normal rotation and normal in reverse rotation, a pulse signal is output if the rotation direction becomes abnormal, so that the device abnormality can be detected.

  In the above description, the pulse signal is masked and fixed to “High” during reverse rotation, but may be fixed to “Low”, and the pulse signal may be fixed during forward rotation. The signal may be masked and fixed to “High” or “Low”.

  Moreover, although the example which used the sensor detection output 22a for the output of rotation speed was demonstrated, you may use the sensor detection output 21a for the output of rotation speed.

It is a block diagram of Embodiment 1 of the rotation state detection apparatus of this invention. It is a figure which shows an example of the internal structure of the rotation direction detection part 3a in Embodiment 1 of the rotation state detection apparatus of this invention. It is a figure which shows an example of the internal structure of the rotation direction discrimination | determination part 4a in Embodiment 1 of the rotation state detection apparatus of this invention. It is a timing diagram of each part signal in case the gearwheel 1 in Embodiment 1 of the rotation state detection apparatus of this invention is carrying out normal rotation. It is a timing diagram of each part signal in case the gearwheel 1 in Embodiment 1 of the rotation state detection apparatus of this invention is carrying out reverse rotation. It is a timing diagram of each part signal in case the rotation direction of the gearwheel 1 in Embodiment 1 of the rotation state detection apparatus of this invention switches from normal rotation to reverse rotation. It is a timing diagram of each part signal in case the rotation direction of the gearwheel 1 in Embodiment 1 of the rotation state detection apparatus of this invention switches from reverse rotation to forward rotation. It is a block diagram of Embodiment 2 of the rotation state detection apparatus of this invention. It is a figure which shows an example of the internal structure of the rotation speed output control part 5a in Embodiment 2 of the rotation state detection apparatus of this invention. It is a timing diagram of each part signal in case the rotation direction of the gearwheel 1 in Embodiment 2 of the rotation state detection apparatus of this invention switches from normal rotation to reverse rotation. It is a figure which shows an example of the internal structure of the rotation speed output control part 5a in Embodiment 3 of the rotation state detection apparatus of this invention. It is a timing diagram of each part signal in case the rotation direction of the gearwheel 1 in Embodiment 3 of the rotation state detection apparatus of this invention switches from normal rotation to reverse rotation. It is a figure which shows an example of the internal structure of the rotation speed output control part 5a in Embodiment 4 of the rotation state detection apparatus of this invention. It is a timing diagram of each part signal in case the rotation direction of the gearwheel 1 in Embodiment 4 of the rotation state detection apparatus of this invention switches from normal rotation to reverse rotation. It is a figure which shows an example of the internal structure of the rotation speed output control part 5a in Embodiment 5 of the rotation state detection apparatus of this invention. It is a timing diagram of each part signal in case the rotation direction of the gearwheel 1 in Embodiment 5 of the rotation state detection apparatus of this invention switches from normal rotation to reverse rotation. It is a block diagram of Embodiment 6 of the rotation state detection apparatus of this invention. It is a figure which shows an example of the internal structure of the rotation direction detection part 3b in Embodiment 6 of the rotation state detection apparatus of this invention. It is a figure which shows an example of the internal structure of the rotation direction discrimination | determination part 4b in Embodiment 6 of the rotation state detection apparatus of this invention. It is a timing diagram of each part signal in case the gearwheel 1 in Embodiment 6 of the rotation state detection apparatus of this invention is carrying out normal rotation. It is a timing diagram of each part signal in case the gearwheel 1 in Embodiment 6 of the rotation state detection apparatus of this invention is carrying out reverse rotation. It is a timing diagram of each part signal in case the rotation direction of the gearwheel 1 in Embodiment 6 of the rotation state detection apparatus of this invention switches from normal rotation to reverse rotation. It is a timing diagram of each part signal in case the rotation direction of the gearwheel 1 in Embodiment 6 of the rotation state detection apparatus of this invention switches from reverse rotation to forward rotation. It is a block diagram of Embodiment 7 of the rotation state detection apparatus of this invention. It is a timing diagram of each part signal in case the rotation direction of the gearwheel 1 in Embodiment 7 of the rotation state detection apparatus of this invention switches from normal rotation to reverse rotation. It is a timing diagram of each part signal in case the rotation direction of the gearwheel 1 in Embodiment 8 of the rotation state detection apparatus of this invention switches from normal rotation to reverse rotation. It is a timing diagram of each part signal in case the rotation direction of the gearwheel 1 in Embodiment 9 of the rotation state detection apparatus of this invention switches from normal rotation to reverse rotation. It is a timing diagram of each part signal in case the rotation direction of the gearwheel 1 in Embodiment 10 of the rotation state detection apparatus of this invention switches from normal rotation to reverse rotation.

Explanation of symbols

1 gear, 1a gear crest, 1b gear trough, 3a, 3b rotation direction detection unit, 4a, 4b rotation direction determination unit, 5a, 5b rotation speed output control unit, 21, 22 sensor, 31a, 32a, 31b , 32b, 33b, 34b DFF circuit, 41a, 42a, 48a AND circuit, 41b, 42b, 43b, 44b, 45b, 46b AND circuit, 47a, 47b OR circuit, 51a, 52a, 53b, 51c, 52c, 53c, 51d AND circuit, 51b NOT circuit, 54a, 55a, 56a transistor circuit

Claims (12)

A first sensor and a second sensor which are arranged opposite to the rotating body and output two rectangular wave-shaped binarization detection signals having different phases according to the rotation;
First rotation direction detection means for observing the detection signal of the second sensor at the rising edge of the detection signal of the first sensor and detecting the rotation direction of the rotating body;
Second rotation direction detection means for observing the detection signal of the second sensor at the fall of the detection signal of the first sensor and detecting the rotation direction of the rotating body;
A rotation state detecting device comprising: a rotation direction discriminating unit that selects and outputs the one with the earlier detection timing from the detection results of the first and second rotation direction detecting units.   2. The rotational state detection device according to claim 1, further comprising a rotational speed detection means for outputting a signal that changes in accordance with the rotational speed of the rotating body based on the detection signals of the first and second sensors.   The rotation state detection device according to claim 1, wherein the first and second sensors are magnetic sensors.   The rotation state detection device according to claim 2, wherein the output level of the rotation speed detection means is switched according to a determination result of the rotation direction determination means.   5. The rotational state detection device according to claim 4, wherein the high output level and / or the low output level of the rotational speed detection means are switched in accordance with a determination result of the rotation direction determination means.   5. The rotational state detection device according to claim 4, wherein the rotational speed detection means stops output in either the forward rotation or the reverse rotation according to the determination result of the rotation direction determination means. A first sensor and a second sensor which are arranged opposite to the rotating body and output two rectangular wave-shaped binarization detection signals having different phases according to the rotation;
First rotation direction detection means for observing the detection signal of the second sensor at the rising edge of the detection signal of the first sensor and detecting the rotation direction of the rotating body;
Second rotation direction detection means for observing the detection signal of the second sensor at the fall of the detection signal of the first sensor and detecting the rotation direction of the rotating body;
Third rotation direction detection means for observing the detection signal of the first sensor at the rising edge of the detection signal of the second sensor and detecting the rotation direction of the rotating body;
A fourth rotation direction detection means for observing the detection signal of the first sensor at the fall of the detection signal of the second sensor and detecting the rotation direction of the rotating body;
A rotation state detecting device comprising: a rotation direction discriminating unit that selects and outputs the one having the earliest detection timing from the detection results of the first to fourth rotation direction detecting units.   8. The rotational state detection device according to claim 7, further comprising a rotational speed detection means for outputting a signal that changes in accordance with the rotational speed of the rotating body based on the detection signals of the first and second sensors.   The rotation state detection device according to claim 7 or 8, wherein the first and second sensors are magnetic sensors.   9. The rotation state detection device according to claim 8, wherein the output level of the rotation speed detection means is switched in accordance with a determination result of the rotation direction determination means.   11. The rotational state detection device according to claim 10, wherein the level of the High output and / or Low output of the rotational speed detection means is switched according to the determination result of the rotation direction determination means.   11. The rotation state detection device according to claim 10, wherein the rotation number detection unit stops output in any of forward rotation and reverse rotation according to a determination result of the rotation direction determination unit.

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