JPS6334817A - Rotating position detector - Google Patents

Abstract

(57) [Abstract] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] The present invention relates to a rotational position detection device that outputs the rotational position of a rotor as a digital electric signal. It is used for counters, door counters, digital switches, and rotation angle detectors.

Read-out counters that count the number of operations of the object to be measured while supporting the station and electrically output the count value can be roughly divided into mechanical types with rotary contacts and electronic types that perform counting operations and output using electronic circuits. There is a formula.

The former mechanical type, for example, rotates the number wheel intermittently and displays the count value from the front display window, while turning on multiple output contacts using a rotary contact fixed to the number wheel.
N, OFF 1. ,, which allows for external reading.

The latter electronic type, for example, counts electrical pulse input using a counter IC and displays this on a display such as a liquid crystal display, while generating a BCD code count output using an output circuit such as a transistor. be.

The mechanical glue-out counter can be turned ON or OFF by bringing the low contact of the gold plate spring into contact with the fixed contact.
Since FF is used, there is a problem that malfunctions occur easily due to external vibration or contact dirt, and high reliability cannot be obtained.

Further, although electronic glue-out counters have high reliability because they do not have mechanical contacts, they require a large number of components such as a counter IC and a liquid crystal display, making it difficult to miniaturize.

The present invention has been made in view of the above-mentioned conventional problems.
The means to solve the problem is to use a rotor in which four markers are provided in a predetermined arrangement along one circumference of the center of rotation, and to detect four markers at positions corresponding to the circumference of the rotor. A rotational position detection device comprising: a stator having means arranged in a predetermined arrangement; and means for outputting ON and OFF signals generated depending on whether or not the four marker detection means detect a marker. It is.

Once in the above configuration, depending on the rotational position that the rotor takes with respect to the stator, the marker detectors of 4 (lI) detect whether or not there is a marker at the corresponding position. The output of the detector represents the rotational position of the rotor as a digital quantity, and this output is outputted from the output means as having a resolution of 1/10 rotation.

1 back plate The present invention will be explained below according to examples.

A lead-out counter (1
), (2) is a cylindrical number wheel which is a rotor, and (3) is a printed circuit board which is a stator.

The number wheel (2) has numbers 0°1.2 for display on its outer circumferential surface.・
..., 9 are printed, and cylindrical gear parts (2a
) (2b) is coaxially protrudingly formed, and the rotation support shaft (4)
It is rotatably fitted into the Also, this number wheel (2) has a marker 4 (H permanent magnet (5) (5)...
are fixed to the inner wall surface of the number wheel in the arrangement shown in Figure 3.

The printed circuit board (3) has a number wheel (2) gear part (
A round hole (3a) into which 2a) is loosely fitted is bored, and a terminal portion (3b) is provided protruding from one end. This printed circuit board (
3), there is a permanent magnet (5) (
5) Four magnetic detection elements (6a) (6b) (6c) (6d) such as Hall elements or magnetoresistive elements are arranged along the locus of... as shown in Fig. 3.
Each magnetic detection element (6a) (6b) (6c) (6d
) determines whether or not it detects magnetism and turns it on and off.
Output means (such as an IC) that outputs a signal from the terminal section (3b)
7) is incorporated. This printed circuit board (3) is
Each magnetic detection element and a permanent magnet are opposed to each other and fixed by means not shown in the drawings without interfering with the movement of the number wheel (2). The gear part (2a) formed on one end surface of the number wheel (2) rotates the number wheel (2) by 1 pitch (1/10 rotation), and the rotation mechanism (2a) shown by the two-dot chain line in the figure 8).Also, when a plurality of the number wheels (2) are connected to form a multi-digit counter, the gear portion (2b) formed on the other end surface of the number wheel (2) rotates by the upper digit. This is for rotating the gear part (2a) of the number wheel by one pitch.

Next, the permanent magnets (5) (5) and the magnetic detection elements (6a) (6h) (6c) (6d) are connected to the rotor number wheel (2) and the stator printed circuit board (3). An example of the arrangement will be explained.

As shown in Figure 3, four permanent magnets (5) (5)...
・ is the number 1 on the number wheel (2). 2. It is attached to the four locations where the 4°8 is placed so that the circumference is internally divided in the ratio of 1:2:4:3.

In addition, four magnetic detection elements (6a) (6b) (6
c) (6d) is the circumference of one circle on the printed circuit board (3) corresponding to the trajectory of the permanent magnets (5) (5)...
It is installed at a position that is internally divided in the ratio of 2:4:3.

Note that the arrangement shown in FIG. 3 is an example, and other arrangements may be used.

When the number wheel (2) is rotated in steps, the number displayed on the number wheel changes from 1 to 2 to 9 to 0 as shown in FIG. At this time,
According to the rotational position of the number wheel (2), magnetic detection elements (6a) (6b) (6c) (6d) which are marker detection means are activated.
) has a permanent magnet (5) (5) which is a marker at its corresponding position.
)... is detected and output. This rotational position [displayed number] and each magnetic detection element (6a) (6b)
(6c) The relationship between the outputs of (ad) is shown in Figure 3 (a)
This is naturally determined from (b)...0), but for ease of understanding, this is diagrammed in Figure 4. If detected, the intersection is indicated with a black circle. In the case of presence detection, an electric signal of "1" is sent from the output means (7) of the magnetic detection element to the terminal part (3b).
If the output is to be output as shown on the right side of FIG. 4, the output will be as shown on the right side of FIG. ...99,0, ten types of 4-bit information with a one-to-one correspondence are obtained. When viewed as a BCD code, this 4-bit information does not directly represent the displayed number, so if you want to convert this output into a BCD code, you must pass it through a predetermined code conversion circuit or use a computer algorithm. Perform code conversion.

In addition, magnetic detection elements (6a) (6b) (6c)
The combinations of outputs in (6d) are limited to the 10 types shown in the upper right corner of Figure 4 as long as the number wheel rotates in steps of 1/10 rotation, but if the number wheel rotates continuously or in steps. If reading is performed during rotation, a combination of 6m outputs as shown in the lower right corner of FIG. 4 may occur.

Since this 6fffi output is not a regular output of the device of this embodiment, it is eliminated by computer processing or the like and reread.

Although one embodiment of the present invention has been described above, the present invention is not limited to this embodiment. Many other embodiments are included within the spirit of the present invention, in which detection means are provided in a predetermined arrangement, and the rotational position of the rotor is detected in a non-contact manner and outputted as a digital electrical signal.

For example, the rotor may be any rotating body to which a marker can be attached, and does not necessarily require numbers for display.

Furthermore, the stator in the present invention can also be called a holder for the marker detection means, and its shape and arrangement can be arbitrary.
For example, it may be a cylindrical body that covers the outer circumference of the rotor.

In addition to the marker and marker detection means that utilize magnetism, those that utilize light can also be used. As an embodiment using light, there is one in which a light source is used as a marker and a photodetector element such as a phototransistor is used as a marker detector.

A specific example of this case is shown in Fig. 5. (10) is a cylindrical rotor having four light emitting diodes (11) (11)... (12a) (12b) (12c) (12
d) are four photodiodes arranged and fixed to a cylindrical stator (13) so as to surround the outside of the rotor (10). In this specific example, four light emitting diodes (11
) (11)... function as markers, and photodiodes (12a) (12b)-(12d) function as marker detectors. Each light emitting diode (11) (
11) ... and photodiodes (12a) (12b
)...(12d) is determined in the same manner as explained using FIG.

Furthermore, in addition to the specific example shown in the gjS5 diagram above, examples that use light include using a reflective plate or a non-reflective plate as a marker,
Some use a light emitter/receiver as the marker detection means. This light emitter/receiver uses a light receiver to detect whether or not the light emitted from its own emitter hits a reflective plate or non-reflective plate attached to a predetermined part of the rotor and is reflected back. It is designed to be detected.

In addition, the configuration of the present invention is such that the number wheel is rotated with a button or the like, and a numerical value is set while looking at the display on the number wheel through the display window, and the set number is electrically read by a digital switch inside the device body. , can be used as is. In addition, if a plurality of rotational position 1 detection devices having the above configuration are connected to form a multi-digit counter, and the rotating shaft to be measured is connected with a gear having a predetermined gear ratio, a high-resolution rotational angle detector can be obtained. It can also be used as

According to the present invention, the rotational position of the rotor can be detected as a digital electrical signal without contact by the relative positional relationship between four markers attached to the rotor and four marker detectors attached to the stator. It can be read with .

This structure has no movable contacts and has a simple counting and display mechanism, so it is highly reliable and can be manufactured in a small size and at low cost.

[Brief explanation of the drawing]

FIG. 1 is a front view of a readout counter which is an embodiment of the present invention, and FIG. 2 is a side view of FIG. 1. FIG. 3(a) To)...ti)(j) is an arrangement example in which a marker and a marker detection means are attached to the rotor and stator in the slip-out counter in FIG.
FIG. 4 is a diagram showing the state in which the positional relationship changes when the rotor and the rotor rotate in steps. FIG. 4 shows the output of the marker detection means corresponding to the number of displayed rotors in each positional relationship shown in FIG. 3. FIG. FIG. 6 is a side view showing another embodiment of the invention of FIG. 5; (1) - Readout counter [rotational position detector],
(2) - Numerical wheel [rotor], (3) - Printed circuit board [stator], (4) - One rotation support shaft, (5) - Permanent magnet [marker], (6a) (6b) (6c) ( 6d)...
・Magnetic detection element, [marker detection means], (7) -・Output means.

Claims (4)

[Claims] (1) A rotor in which four markers are provided in a predetermined arrangement along one circumference of the rotation center, and four marker detection means are provided in a predetermined arrangement at positions corresponding to the circumference of the rotor. 1. A rotational position detecting device comprising: a stator having a fixed position; and means for outputting ON and OFF signals generated depending on whether or not the four marker detecting means detect a marker. (2) The rotational position detection device according to claim 1, wherein the marker is a permanent magnet and the marker detection means is a magnetic detection element. (3) The rotational position detection device according to claim 1, wherein the marker is a light source and the marker detection means is a photodetection element. (4) The rotational position detection device according to claim 1, wherein the marker is a reflector or a non-reflector, and the marker detection means is a light projector/receiver.