JPS61250563A - Apparatus for detecting rotation - Google Patents

Abstract

PURPOSE:To detect even a rotary direction even if one phase gets out or order without lowering detection accuracy, by combining the outputs of arbitrary two sets of rotation detectors among three sets of ones provided so as to be mutually shifted by the same phase to detect a rotary speed and a rotary direction. CONSTITUTION:Rotation sensors S1-S3 output rotation detecting pulses at the cycle corresponding to the rotary speed of a rotary disc and said pulses are amplified by amplifiers A1-A3 to be supplied to FFF1-F6. The Q output terminals of FFF1-F6 are respectively connected to one input terminals of two-input AND circuits Y1-Y6 and reversal Q output terminals of FFF1 and F2, F3 and F4 and F5 and F6 are connected to the other input terminals of the AND circuits Y1, Y2-Y6 mutually corresponding to the partner side by cascade connection. The outputs of the circuits Y1-Y3 are inputted to a three- input OR circuit O1 for discriminating a positive rotary direction and the outputs of the circuits Y4-Y6 are inputted to a three-input OR circuit O2 for discriminating a reverse direction to take each logical sum. The logical outputs of said circuits O1, O2 come to a rotary direction detecting signal comprising the combination of three-phase outputs of sensors S1-S3.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a rotation detection device used, for example, in a vehicle speed sensor of an automobile.

(Prior art) The speed at which electronics technology has recently been introduced in the field of automobile technology has been remarkable, and it is not only used in engine systems such as engine electronic fuel injection control systems and vehicle constant speed cruise control systems, but also in the field of normal driving systems, as well as in steering control and other areas. This is now even extending to the field of secondary driving systems such as suspension control.

In all of these control systems, the speed of the vehicle plays a very important role as a bias input element, and the accuracy and reliability of the detection device determines the performance of the control system itself.

As a means for detecting vehicle speed, a through hole is formed in the circumferential direction of a rotary disk, and a light emitting body such as an LED and a light receiving body such as a phototransistor are connected through the through hole in the conventionally commonly used means for detecting vehicle speed. There is a device in which the rotary disks are arranged opposite each other, and a pulse signal output corresponding to the rotational speed is obtained with a light reception and light blocking period that changes according to the rotation of the rotating disk.

However, in that case, if the through holes are formed in a single row and the light emitting body and the light receiving body are in a single set, it may become impossible to detect the rotation sensor at all if the single set of rotation sensors malfunctions. Since it is easy to cause an error in the detection signal if the perforations are in a single row, two rows of the above-mentioned through-holes are formed on a concentric circumference with mutually changing phases, and the above-mentioned rotation sensors are also arranged in two sets corresponding to the two rows. There is a system that improves detection accuracy by providing a rotation sensor, and even if one set of rotation sensors fails, the remaining rotation sensors can maintain the minimum detection function (for example, see Utility Model Application Publication No. 172856/1983). .

However, in such a configuration, even if the - group of rotation sensors fails, only the rotation speed (or rotation number) can be detected, and the rotation direction cannot be detected at all. Moreover, there is a drawback that it is not necessarily easy to form two rows of through holes concentrically and with different phases on the same rotating disk with high precision.

(Object of the Invention) The present invention has been made to improve the above-mentioned drawbacks, and is to provide at least three sets of rotation detecting means with respect to the rotating disk so as to be shifted by the same phase. By combining the outputs of any two sets to detect the rotation speed and rotation direction, even if one phase fails, the detection accuracy will not be reduced, and the rotation direction It is an object of the present invention to provide a rotation detection device that is also capable of detection.

(Means for Achieving the Object) In order to achieve the above object, the present invention is configured such that each output signal is outputted with the same phase shift to a rotating disk connected to a rotating shaft. at least three rotation detecting means installed in the rotation detecting means; and a phase determining means for relatively determining a phase shift direction from the outputs of any two sets of rotation detecting means among the at least three rotation detecting means. , and rotational direction detection means for determining the rotational direction of the rotating disk based on the output of the phase determination means.

(Function) According to the above means, each output signal is outputted with the same phase shift to the rotating disk by at least three times.
A set of rotation detecting means is provided, any two of which
Since the rotation speed and rotation direction are detected by the combination of the outputs of the rotation detection means of the set, it is possible to detect the rotation speed and rotation direction even if one of the rotation detection means fails. There is no decrease in accuracy.

Further, the rotation speed can still be detected even if two sets of rotation detection means fail.

(Example) FIGS. 1 to 4 show a rotation detection device according to an example of the present invention.

First, FIG. 1 is a perspective view showing the configuration of the sensor portion of the rotation detecting device, and reference numeral 1 indicates a predetermined (constant) sensor portion in the circumferential direction.
It is a rotating disk in which a plurality of through holes 2 are formed at intervals.

This rotating disk l is connected to a rotating shaft 3 such as a wheel drive shaft, and rotates in accordance with the rotation of the rotating shaft 3.

On the other hand, symbols S and ~S3 refer to the through holes 2 of the rotating disk 1.
．． 2... Three sets of rotation sensors installed corresponding to the section (
(corresponds to the rotation detection means in the claims),
They are located at a distance of 120 degrees from each other, and consist of a U-shaped body with, for example, a light-emitting diode (LED) as a light-emitting part on the top and a phototransistor as a light-receiving part on the bottom, and their output signals are also rotated. The output is shifted by the same phase in each direction.

These rotation sensors S, ~S, output rotation detection pulses at a period corresponding to the rotation speed of the rotating disk 1, and as shown in FIG. 2, this output is amplified by an amplifier AIA a. After the D-type (delay type) flip-flop circuit F l
-Fa Provided as either input of a.

The input terminals of the flip-flop circuits F, -F8 are connected as shown, and the output of the amplifier A (FIG. 3a) is the data input of the flip-flop circuit F1°F, and the input terminals of the flip-flop circuit F, ,F.

The clock is human powered. Further, the output of amplifier A (FIG. 3b) is output from flip-flop circuit F3. It becomes the data input of F, and the clock input of the flip-flop circuits F,, F,. Further, the output of the amplifier A (FIG. 3C) serves as a data input for the flip-flop circuits Fs and Fs, and a clock input for the flip-flop circuits Fs and Fa.

Therefore, the flip-flop circuit F l+F t has the timing (however, F
The output of the amplifier A is taken in (the clock edges of I and Ft are different), and the Q and Q outputs corresponding to the output of the amplifier A are held until the next clock input is supplied. In addition, other flip-flop circuits F, F6, F
, and F6 operate in a similar manner.

On the other hand, each of the Q output terminals of the flip-flop circuits F, ~F6 is connected to a corresponding two-man power AND circuit Y1~Y,
is connected to one input terminal of the flip-flop circuits F, and F1, F3 and F4, F, and F, respectively, and the Q output terminals of the flip-flop circuits F, F, and F correspond to each other.
It is connected in cascade to the input terminals on the other side of Y*, Y3, Y, and Y6.

Therefore, the AND circuit Y inputs the Q output of the flip-flop circuit F and the S output of the flip-flop circuit F, and outputs the AND output (FIG. 3d).
, inputs the Q output of flip-flop circuit F, and the Q output of flip-flop circuit F1, and calculates their AND output (
3e), the AND circuit Y3 inputs the Q output of the flip-flop circuit F3 and the Q output of the flip-flop circuit F4, and outputs the AND output (FIG. 3 d). The AND circuit Ys outputs the AND output (Fig. 3e) by manually inputting the Q output of the flip-flop circuit F4 and the Q output of the flip-flop circuit F, and , and the AND circuit Y inputs the Q output of the flip-flop circuit F and the Q output of the flip-flop circuit F, and outputs the AND output (Fig. 3d). A logical product output (FIG. 3e) is output respectively. The above flip-flop circuit F t "" F * and the above AND circuit Y l
-Ys constitutes the phase discrimination means in the claims.

Then, the above AND circuit Y I, Y s , Y s
The output (Fig. 3 d) is sent to the three-man OR circuit 0° for determining the forward rotation direction, and to the AND circuit Y t , Y 4 , Y
The output of s is an OR circuit 0.s for determining the reverse direction, which is also powered by three people. are respectively inputted to , and their respective logical sums are taken. These OR circuits are 01.0! (corresponding to the rotational direction detection means in the claims)
) is a rotation direction detection signal consisting of a combination of the three-phase outputs of the rotation sensors Sr, St, and Ss.

As a result, when the output of the OR circuit 01 becomes H (high level) according to the time charts of FIGS. 3(a) to (g), the rotation direction of the rotating disk 1 h<S l→S. , that is, in the normal rotation direction, and when the output of the OR circuit O2 is H (high level), the rotating disk l is S, -S,
This indicates that the rotation is in the direction of rotation, that is, in the reverse direction. On the other hand, if the output of the OR circuit o1 is at a low level (low level), it indicates that either the forward or reverse direction is unknown or the reverse direction is present, and at least it is not the forward direction.
If the output of the circuit O1 is L, this indicates that the forward/reverse direction is unknown or that the rotation direction is the forward rotation direction, at least not the reverse rotation direction. Therefore, if the above-mentioned state is now assumed, as shown in the time charts of FIGS. 4(a) to 4(k), the output of the rotation sensor S itself will no longer generate the correct rotation pulse, and the rotation sensor S Flip-flop whose data input is the output of -circuit Fs, F
The input state of s changes as shown in FIG. 4C. In contrast, its clock input does not change.

Therefore, the flip-flop circuit F reads the input shown in FIG. 4C using the clock input shown in FIG. generates Q output. Also, on the other hand,
The data input of flip-flop circuit F6 changes similarly.

Furthermore, as a result of the above, the Q of the flip-flop circuits F3+F4 whose clock input is the output of the rotation sensor S3,
Q output also changes. Therefore, as a result of the above, the output of the AND circuit Y is as shown in FIG.
The output changes as shown in the fourth diagram. However, in this case, the outputs of the AND circuits Yt, Y, Y, for determining the reverse direction (e, g, i in FIG. 4) do not change. Therefore, OR
The output of circuit O9 remains 17.

On the other hand, since the rotation sensors S, , S, are normal, the output of the AND circuit Y1 maintains the H output (FIG. 3 d, FIG. 4 d) as in normal operation. Therefore, O
The output of the R circuit oI is finally H, and it is determined that the normal rotation direction is normal.

(Effects of the Invention) As explained above, the present invention provides a rotary disk which is installed so that each output signal is outputted with the same phase shift to the rotating disk connected to the rotating shaft. At least three rotation detecting means, a phase determining means for determining a relative phase shift direction from the outputs of any two sets of rotation detecting means among the at least three rotation detecting means, and this phase determining means. and a rotational direction detection means for determining the rotational direction of the rotating disk based on the output of the rotating disk.

Therefore, according to the present invention, at least three sets of rotation detecting means are provided so that the respective output signals are outputted with the same phase shift with respect to the rotating disk, and any two sets of the rotation detecting means are provided. Since the rotation speed and rotation direction are detected by the combination of the outputs of the rotation detection means, the rotation speed and rotation direction can be detected even if one of the rotation detection means breaks down, and the detection accuracy can be improved. There was no decrease in

Further, the rotation speed can still be detected even if two sets of rotation detection means fail.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing the configuration of a rotation sensor section of a rotation detection device according to an embodiment of the present invention, FIG. 2 is an electric circuit diagram of the rotation detection device, and FIGS. 5 is a time chart showing circuit operation. l...Rotating disk 3...Rotating shaft S1-S3...Rotation sensor F, ~F...Flip-flop circuit Y l-Y s...AND circuit O1, Ot...OR circuit /...Rotating disk 3...Rotating shaft S1-S3...Pipe rotation sensor Fl-F6...Flip-flop circuit Y1-Y6...
-AND circuit Ql, Q2/urn 11OR circuit (Q) (d) Fig. 3 (Q) (i)□ (j) (k)□ Fig. 4

Claims (1)

[Claims] 1. at least three rotation detecting means installed so that the respective output signals are outputted with the same phase shift with respect to the rotating disk connected to the rotating shaft;
a phase determining means for determining a relative phase shift direction from the outputs of any two rotation detecting means among the two rotation detecting means; and a phase determining means for determining the direction of rotation of the rotating disk based on the output of the phase determining means. A rotation detection device comprising a rotation direction detection means.