JPH11287605A - Reference position setting apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To detect the rotary position of a small diameter gear from the reference position of a large diameter gear at high resolution and high accuracy. SOLUTION: This reference position setting apparatus is provided with a small diameter gear 3 and a large diameter gear 2, which mesh with each other either directly or via a worm screw 1 to rotate relative to each other, and rotary position sensors 7, 8 which detect the rotary positions of the small diameter gear 3 and the large diameter gear 2, respectively. The numbers of the teeth of the small diameter gear 3 and those of the large diameter gear 2 are set so that the small diameter gear 3 is shifted from a reference position by an angle θ by making N rotations for each one rotation of the large diameter gear 2. A plurality of rotary position sensors 8 for detecting the rotary position of the small diameter gear 3 are placed in positions which are shifted from one another, each by the angle θ with respect to the reference position.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reference position setting device for setting a mutual reference position of a large-diameter gear and a small-diameter gear directly meshing with or without a worm screw.

[0002]

2. Description of the Related Art When a vehicle height, that is, a vehicle body position is changed by a vehicle height adjustment device mounted on a vehicle, a predetermined value is provided to the vehicle height adjustment device based on at least the current vehicle body position or a reference vehicle body position. Will work.

A vehicle height sensor for detecting a current vehicle position or a reference vehicle position is disposed on the vehicle body, and is configured to input a signal to a controller constituting a vehicle height adjusting device.

Incidentally, the controller processes the signal from the vehicle height sensor and outputs a vehicle height adjustment signal to a hydraulic supply / discharge source or a control valve for expanding and contracting a vehicle height adjuster constituting the vehicle height adjustment device.

There have been proposed various types of vehicle height sensors for detecting a vehicle body position, and any of these vehicle height sensors can detect a current vehicle body position or a reference vehicle body position in a vehicle. .

Further, these proposed vehicle height sensors are capable of detecting not only the vehicle position serving as a reference, that is, for example, the high vehicle height position and the low vehicle height position after adjustment, but also the medium vehicle height position. Is configured.

[0007] Therefore, depending on the configuration, the size of the sensor itself tends to be increased, and when the size is increased, there is a problem that the distribution of the vehicle height sensor on the vehicle body is reduced.

Further, the controller performs a comparison process between three types of vehicle height adjustment signals, for example, low, medium, and high, from the vehicle height sensor and a preset reference value and outputs a predetermined signal. Since the vehicle height adjuster is configured to control the expansion and contraction based on this output, the controller itself is complicated, and the control structure of the vehicle height adjustment device is also complicated.

As a result, the overall configuration of the vehicle height adjustment device becomes large, the mountability of the vehicle height adjustment device on the vehicle is reduced, and the vehicle height adjustment device tends to be expensive. , Making it unsuitable for mounting on popular cars.

On the other hand, a large-diameter gear and a small-diameter gear, at least one of which is driven to mesh with each other,
A rotation position sensor that detects the rotation position of each of the large-diameter gear and the small-diameter gear by an on / off operation of a switch;
A reference position setting device has been proposed which sets two rotational positions of a large-diameter gear and a small-diameter gear when these rotational position sensors are simultaneously turned on as reference positions for adjusting the vehicle height.

[0011]

However, such a conventional reference position setting device basically has a structure in consideration of use as a vehicle height sensor.
The reverse rotation has a problem that only the same rotation speed can be measured.

Further, since only two small-diameter gears and one large-diameter gear, which are the minimum number required for vehicle height control, are provided with rotational position sensors for detecting the rotational positions of the small-diameter gear and the large-diameter gear, respectively. However, the rotational position estimated by counting the pulses from the reference position is not an absolute position, and as a result, the accuracy of controlling the vehicle height is reduced.

SUMMARY OF THE INVENTION The present invention solves the above-described problems, and can detect the rotation position of a small-diameter gear from a reference position of a large-diameter gear with high resolution and high accuracy. It is an object of the present invention to provide a reference position setting device that can freely and easily set a position to an arbitrary position.

[0014]

In order to achieve the above object, a reference position setting device according to the first aspect of the present invention comprises a small-diameter gear and a large-diameter gear, which rotate relative to each other directly or via a worm screw, A rotation position sensor for detecting the rotation position of each of the small-diameter gear and the large-diameter gear is provided so that the number of teeth of the small-diameter gear and the number of teeth of the large-diameter gear are set to N rotations per rotation of the large-diameter gear. The reference position is set so as to be shifted from the reference position by an angle θ, and a plurality of rotation position sensors for detecting the rotation position of the small-diameter gear are arranged at positions shifted by an angle θ from the reference position.

According to a second aspect of the present invention, in the reference position setting device, a rotational position sensor is provided for each of the magnets provided on each of the small-diameter gear and the large-diameter gear, and the rotation locus of each of the magnets. And a Hall element disposed opposite to the Hall element.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment of the present invention will be described with reference to the drawings. FIGS. 1 and 2 are a front view and a plan view showing a schematic configuration of a reference position setting device of the present invention. In this reference position setting device, a large-diameter gear 2 and a small-diameter gear 3 are meshed with a worm screw 1 and magnets 5 and 6 are arranged on the large-diameter gear 2 and the small-diameter gear 3, respectively.
Of these, one Hall element 7 is arranged at a position facing the rotational locus of the magnet 5, and a plurality of, in this case, 12 Hall elements 8 are arranged at a position facing the rotational locus of the magnet 6.
To 19 are arranged.

Each of the Hall elements 7 and 8
Numerals 19 to 19 are attached to the fixed substrate 4 on the fixed part 20 side such as a vehicle height adjusting device.

The number of teeth of the large-diameter gear 2 and the small-diameter gear 3 is adjusted so that the small-diameter gear 3 rotates N times with respect to one rotation of the large-diameter gear 2 from the reference position, and further shifts by an angle θ from the reference position. The Hall elements 8 to 19 for setting and detecting the rotational position of the small-diameter gear 3 are arranged one by one at positions shifted by θ from the reference position.

When the magnets 5 and 6 and the Hall elements 7 and 8 are positioned on a straight line, the reference positions of the large-diameter gear 2 and the small-diameter gear 3 are set.

The number of teeth of the small-diameter gear 3 does not become a divisor of the number of teeth of the large-diameter gear 2 and is not divisible by the number of rotations of the large-diameter gear 2 from a reference position in one direction. It is set to be.

Therefore, for example, when the number of teeth of the large-diameter gear 2 and the small-diameter gear 3 is 249 and 49, respectively, when the large-diameter gear 2 is rotated once clockwise from the reference position,
The small-diameter gear 3 rotates approximately 5.08 counterclockwise from the reference position, and the magnet 6 is positioned at a position shifted by a predetermined angle θ from the reference position.

Therefore, until the large-diameter gear 2 rotates 12 times, the magnets 5 and 6 and the Hall elements 7 and 8 do not become linear, and the small-diameter gear 3 moves relative to the large-diameter gear 2 from the reference position. It shifts in the rotation direction and returns to the reference position at the position after 12 rotations.

Here, the Hall element 7 is connected to one of the large-diameter gears 2.
The rotation is adjusted by counting the number of pulses of each of the Hall elements 7, 8 to 19 since one pulse is output by rotation and each of the Hall elements 8 to 19 outputs one pulse by one rotation of the small-diameter gear 3. Position can be detected.

The reference position setting device includes a Hall element 7 provided on each of the large-diameter gear 2 and the small-diameter gear 3,
Numeral 8 turns on (outputs a pulse voltage) only when each of them faces directly above the magnets 5 and 6, and determines that the small-diameter gear 3 is at the reference position with respect to the large-diameter gear 2 at this time.

Next, the operation will be described. In the present invention, as described above, the number of teeth of the large-diameter gear 2 and the small-diameter gear 3 is increased by N rotations of the small-diameter gear N per rotation of the large-diameter gear 2. Further, the magnet 6 is set at a position shifted by an angle θ from the reference position, and only one of the Hall elements 8 to 19 is turned on at a reference position of the large-diameter gear 2. I have.

Assuming that the magnets 5 and 6 and the Hall elements 7 and 8 are at the reference positions as shown in FIG. 2, the Hall element 7 is turned on and the Hall element 8 is turned on.

Here, when the worm gear 1 is rotated so that the large-diameter gear 2 rotates clockwise, the small-diameter gear 3 rotates counterclockwise.

When the magnet 5 comes to a position where the large-diameter gear 2 makes one rotation and the Hall element 7 is turned on again, the small-diameter gear 3 rotates N times and the angle θ, and the magnet 5 is placed on the Hall element 9. 6, the Hall element 9
Is turned on.

Further, when the large-diameter gear 2 is rotated,
When the Hall element 7 is turned on at the second rotation, the Hall element 10 is turned on, and at the third time, the Hall element 11 is turned on.

On the other hand, when the worm gear 1 is rotated so that the large-diameter gear 2 rotates counterclockwise, the small-diameter gear 3 rotates clockwise.

When the magnet 5 comes to a position where the large-diameter gear 2 makes one rotation and the Hall element 7 is turned on again, the small-diameter gear 3 rotates N times and moves to a position shifted by an angle θ from the reference position. 6 comes.

As a result, the Hall element 19 is turned on.

Further, when the large-diameter gear 2 is rotated,
When the Hall element 7 is turned on in the second rotation, the Hall element 18 is turned on, and in the third rotation, the Hall element 17 is turned on.

In this manner, the number of rotations of the large-diameter gear 2 from the reference position up to M / 2 rotations is reliably detected for M Hall elements arranged at positions shifted by the angle θ on the rotation trajectory of the magnet 6. be able to.

By detecting the number of rotations of the small-diameter gear 3 and the position of the hall element in the ON state, 360
The phase of the large-diameter gear 2 from the reference position can be detected with an accuracy of an angle of / (M · N + 1).

For example, assuming that the rotation speed of the small-diameter gear 3 is n and the position of the hall element in the ON state is a position which is shifted by m from the position at which the large-diameter gear 2 was previously turned on at the reference position, the large-diameter gear Gear 2 is shifted from the reference position by $ 360 / (M
・ N-1)｝ ・ Magnet 5 at the position shifted by (nM + m)
There will be.

If the Hall element 8 is currently in the ON state, the large-diameter gear 2 rotates in any direction, and if the small-diameter gear 3 rotates θ, the Hall element 9 or the Hall element 19 is in the ON state. It can be seen from the above that whether the large-diameter gear 2 has rotated in the clockwise direction or the counterclockwise direction is detected.

Further, by arranging one of the Hall elements 8 to 19 to be turned on at the reference position of the large-diameter gear 2, the turned-on position is set to the reference position of the large-diameter gear 2 and the small-diameter gear 3. Therefore, there is no need to set only the Hall element 8 as the reference position as described above, and it is not necessary to set such a reference position in advance.

[0039]

As described above, according to the first aspect of the present invention, a small-diameter gear and a large-diameter gear that are engaged with each other directly or via a worm screw and rotate relatively to each other are provided. A rotation position sensor for detecting the rotation position is provided so that the number of teeth of the small-diameter gear and the number of teeth of the large-diameter gear are shifted N times from the reference position by one rotation of the large-diameter gear. And a plurality of rotational position sensors for detecting the rotational position of the small-diameter gear are arranged at positions shifted by an angle θ around the above-mentioned reference position. A sensor is arranged so that at the reference position on the large-diameter gear side, it is possible to know which rotational position sensor on the small-diameter gear is on, and in addition to detecting the reference position, the number of rotations of the large-diameter gear from this reference position. To In addition, the effect of reliably detecting up to half the number of rotation position sensors can be obtained.

In addition to knowing the absolute position (rotational position and rotation direction) of the large-diameter gear with respect to the reference position, high-precision detection of the rotation position is possible. By arranging, the reference position of the large diameter gear and the small diameter gear can be set freely.

According to the second aspect of the present invention, the rotational position sensor is provided so as to oppose each magnet provided on each of the small-diameter gear and the large-diameter gear, and the rotational trajectory of each magnet. The above-mentioned reference position and rotation position of the large-diameter gear and the small-diameter gear on which the magnets are installed can be measured with high sensitivity and high precision by detecting the magnet magnetic field with high accuracy and low cost. The effect is obtained.

[Brief description of the drawings]

FIG. 1 is a side view schematically showing a reference position setting device according to an embodiment of the present invention.

FIG. 2 is a plan view of the reference position setting device shown in FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Worm screw 2 Large diameter gear 3 Small diameter gear 5, 6 Magnet 7 thru 19 Hall element as rotation position sensor

Claims (2)

[Claims] A small-diameter gear and a large-diameter gear that are engaged with each other directly or via a worm screw and relatively rotate, and a rotation position sensor that detects a rotation position of each of the small-diameter gear and the large-diameter gear; The number of teeth of the small-diameter gear and the number of teeth of the large-diameter gear are set such that the small-diameter gear rotates N times with respect to one rotation of the large-diameter gear and deviates from the reference position by an angle θ. A reference position setting device, wherein a plurality of sensors are arranged at positions shifted by an angle θ about the reference position. 2. The method according to claim 1, wherein the rotation position sensor comprises a magnet provided on each of the small-diameter gear and the large-diameter gear, and a Hall element arranged to face the rotation locus of each of the magnets. The reference position setting device according to claim 1.