JPH07164930A - Power seat position detection method and position detection device - Google Patents

Abstract

(57) [Abstract] [Purpose] To enable detection of the absolute position of a movable member in a power slide without complicating the structure. [Structure] Branch circuit reed switch for series circuit
Monitor the output voltage at the 12 outputs. Then, the series of reed switches 12 are fixed to the upper rail 20, the magnetic body 14 having the same magnetic pole width W2 as the arrangement pitch W1 of the reed switches is fixed to the lower rail 24, and the reed switch turned ON by the proximity of the magnetic bodies is The seat position is detected from the position of the reed switch, which is determined by the output voltage from the branch circuit.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power seat position detecting method and position detecting device for detecting the position of a corresponding movable member of a power seat operating under the drive of a motor.

[0002]

2. Description of the Related Art For example, a so-called power seat, which moves a seat itself, a seat back or the like under the control of driving a motor, is widely known as a seat for an automobile or the like.

In such a power seat, the motor is connected to, for example, a motor control device equipped with a microcomputer and the like.
Based on output signals according to various input signals, motor drive control can be performed according to manual control or automatic control.

Here, the power seat is provided with, for example, a position detection device for detecting the position of a movable member as an object and causing the microcomputer of the motor control device to recognize the position. As the position detection device, for example, an external measurement type that directly detects the operation of the movable member by turning the switch on or off, or an internal type that uses a reed switch or potentiometer provided on the output shaft or gear of the motor, etc. The formula is well known.

At present, in Japan, there is a combination of a disk-shaped magnet that rotates integrally with the output shaft of the motor and a reed switch that can be turned ON / OFF depending on the polarity of the rotating magnet. And reed switch O
The mainstream method is an internal measurement system in which the position of the movable member is recognized under the monitoring of the pulse output accompanying N and OFF.

[0006]

However, in the known internal measurement structure having the combination of the magnet and the reed switch, the driving amount of the motor, that is, the corresponding movable member is determined by counting the number of outputs of the output pulse. However, the position of the movable member with respect to the base point of the front most, the rear most, and the like, that is, the absolute position of the movable member cannot be easily recognized.

On the other hand, in the configuration using the potentiometer, since the position of the movable member is detected by detecting the fluctuation of the voltage value from the base point, the absolute position of the movable member can be recognized. However, since the output from the potentiometer is an analog signal, it must be converted to a digital signal by the A / D converter when it is output to the microcomputer. Therefore, the configuration tends to be complicated, and the device itself tends to be expensive due to the addition of the A / D converter.

According to the present invention, the structure is not complicated.
An object of the present invention is to provide a position detection method and a position detection device for a power seat that can detect the absolute position of a movable member.

[0009]

To achieve this object, according to the position detecting method of the power seat of the present invention, the output voltage of the reed switch of the branch circuit with respect to the series circuit is monitored. Then, a series of reed switches arranged adjacent to each other, one of the magnetic bodies is moved with respect to the other under the movement of the movable member with respect to the fixed member, and the reed switch turned on by the proximity of the magnetic body The position of the movable member with respect to the fixed member is detected from the position of the reed switch, which is determined by the output voltage from the branch circuit.

[0010]

According to the present invention, since the position of the reed switch that has been turned on is determined based on the fluctuation of the voltage value from the base point, it is possible to detect the absolute position of the movable member with respect to the fixed member. Then, since the position of the movable member can be detected by the output voltage in the same manner as the digital signal, the A / D converter becomes unnecessary and the configuration is simplified.

[0011]

Embodiments of the present invention will now be described in detail with reference to the drawings.

As shown in FIGS. 1 and 2, a power seat position detecting device 10 according to the present invention comprises a plurality of reed switches 12 and a magnetic body 14 for turning on the reed switches. The position of the movable member with respect to the fixed member of the power seat can be detected.

Here, the reed switch 12 and the magnetic body 14 are used.
However, the position detecting device 10 is configured to be provided on the power slide 16 having the seat itself as a movable member and capable of detecting the position of the power seat (seat) 18 associated with the operation of the power slide (see FIG. 3). .

As can be seen from FIGS. 2 and 3, the power slide 16 includes an upper rail 20 fixed to the seat 18 and a lower rail 24 fixed to the floor surface 22. The upper rail is slidably incorporated in the lower rail via rolling elements such as 26 and rollers 28.

The power slide 20 is usually operated under the control of driving a motor (not shown) by a motor controller (not shown). It is well known and these are not the subject of the present invention and will not be described in detail here.

As shown in FIG. 1, in the present invention,
A series of reed switches 12 are arranged at equal intervals at a specific pitch W1 by, for example, attachment to a printed circuit board 30 that has been etched into a predetermined pattern, and a case 32 is formed.
Unitized under storage in.

Here, as can be seen from FIG. 4 in addition to FIG. 1, a series of reed switches whose one ends are connected to each other.
The other ends of 12 (12-1 to 12-10) are connected to each other on a printed circuit board 30 between resistors in a series circuit including a plurality of resistors 34. Here, the reed switch 12 (12-
1 to 12-10) are respectively connected between the resistors 34 (34-1 to 34-11) of the series circuit, the number of resistors is S when the number of reed switches is S. One more
(S + 1).

Resistor 34 (34-1 to 34-11), reed switch
Each terminal of the series circuit and the branch circuit composed of 12 (12-1 to 12-10) is connected to the motor control device via, for example, the connector 36 and serves as an input terminal 36-1 and 36-2. Between,
The specified input voltage E is applied. And, in this invention, in the motor control device, the input terminals 36-1, 36-2,
The output voltage Eo between the output terminal of the branch circuit and the terminal 36-3 is monitored.

As shown in FIGS. 1 and 2, a printed circuit board 30 is provided.
Is housed in the case 32, and is tightened together with the cover 40 by interposing the printed circuit board with a set screw (not shown) or the like, so that the printed circuit board, that is, the series of reed switches 12 (12-1 to 12-). 12-10) is unitized in the case.

The printed circuit board 30 is adjacent and fixed to the case 32, for example, via a spacer 42 for ensuring a certain space on the back surface.

Here, as shown in FIGS. 1 and 2, the reed switches 12 (12-1 to 12-10) are all printed circuit boards.
It is arranged and attached to the arrangement hole 44 provided in 30. In such a configuration, the reed switch 12 (12-1 to 12
Since the thickness of (-10) is absorbed in the arrangement hole 44, so-called floating of the reed switch with respect to the printed circuit board 30 can be prevented, and for example, the distance of the reed switch with respect to the vertical wall 32a of the case 32 can be easily equalized. It comes off.

The unitized case 32 is connected to the upper rail 20 of the power slide via the bracket 45.
Fixed against.

Then, as shown in FIG. 1 and FIG.
14 is arranged adjacent to the unitized case 32 of the reed switch 12 (12-1 to 12-10) and is fixed to the lower rail 24 of the power slide. Magnetic body 14
Has a permanent magnet 46 having a magnetic force for turning on the adjacent reed switch 12 and is housed in a synthetic resin case 52 with iron plates 48 and 49 as upper and lower magnetic poles and a cover 54. It is unitized by fitting.

The width of the magnetic permanent magnet 46 and the iron plates (magnetic poles) 48, 49, that is, the magnetic pole width W2, is the reed switch 12
(12-1 to 12-10) are formed with the same arrangement pitch W1.

In such a structure, the series of reed switches 12 (1) are operated under the operation of the power slide 16, that is, the slide of the upper rail 20 with respect to the lower rail 24.
2-1 to 12-10) move laterally of the magnetic body 14 with respect to the magnetic body. Then, for example, when the power slide 16 is stopped at any position of the seat 18, the magnetic material is
One of the reed switches 12 adjacent to 14 turns on under the magnetic force of the magnetic material.

At this time, as shown in FIGS. 4 and 5, a series of reed switches 12 (12-1 to 12-10) are used to form the resistor 34.
Since a branch circuit for the series circuit of (34-1 to 34-11) is formed, when one of the reed switches is turned on, the number of resistors combined in the series circuit is limited,
The resistance value in the circuit is changed.

For example, assuming that the reed switch 12-4 is turned on by the magnetic body 14, the combined resistance of the resistors 34-1 to 34-7 becomes the resistance value in the circuit, and the voltage corresponding thereto becomes It is output as the output voltage Eo. When the reed switch 12-8 is turned on, the resistors 34-1 to
The combined resistance up to 34-3 becomes the resistance value in the circuit, and the voltage corresponding to it is output as the output voltage Eo.

In the embodiment, for example, the output from the ON operation of the reed switch 12-1 is set, with the slide end position (rearmost) of the seat 18 on which the reed switch 12-1 is turned ON as the measurement base point. The amount of slide of the sheet 18 is detected based on the amount of change in voltage.

That is, in this configuration, as shown in FIG. 5, the output voltage Eo from the branch circuit fluctuates stepwise in accordance with the reed switch 12 (12-1 to 12-10) which has been turned on. Therefore, by monitoring the output voltage Eo with the motor control device, it is possible to easily determine which reed switch has been turned on. Then, the reed switch 12 (12-
(1 to 12-10), the position of the upper rail 20 with respect to the lower rail 24 of the power slide, that is, the position of the seat 18 can be detected.

The seat position resolution at this time is 1 / (S-1) division, and the voltage resolution of the output voltage Eo is 1 / (S
+1).

As described above, according to the position detecting method of the power seat of the present invention, the seat from the base point is measured by the so-called external measurement method which directly measures the moving amount of the upper rail 20 with respect to the lower rail 24 of the power slide. Since the slide distance is detected, the absolute position of the sheet 18 can be easily detected from the base point.

Since the position of the seat 18 from the base point is directly detected under the ON operation of the reed switches 12 (12-1 to 12-10), the accumulation of mechanical errors is surely prevented. it can.

Further, under the monitoring of the output voltage Eo, the seat
Since 18 positions are detected digitally, an A / D converter for converting analog signals into digital signals is not required. Therefore, the configurations of the position detection device 10 and the motor control device can be sufficiently simplified.

Further, according to the position detecting device 10 of the power seat of the present invention, the above method can be appropriately performed, and therefore, without using the analog potentiometer,
The absolute position of the seat 18 can be easily detected. Since the reed switch 12 (12-1 to 12-10) and the magnetic body 14 can be combined to form a non-contact type, the position detecting device 10 having excellent durability can be easily secured.

Here, in the position detecting device 10 of the power seat of the present invention, for example, the detection positions at the frontmost and rearmost reed switches 12-1 and 12-10 are set after the upper rail 20 is slid with respect to the lower rail 24. When the limit position (rearmost) and the slide front limit position (frontmost) are set, the rearmost output voltage
Eo (R) and the frontmost output voltage Eo (F) are given in the following formulas 1 and 2, respectively.

[0036]

[Equation 1] {1 / (S + 1)} E ≦ Eo (R) <(1 / S) E

[0037]

[Equation 2] {S / (S + 1)} E ≧ Eo (F)> {(S-1) / S} E

Therefore, by storing the output voltages Eo (R) and Eo (F) in advance and comparing this with the measured value of the output voltage Eo, the seat 18 for the rearmost and frontmost can be obtained.
It is possible in the power seat position detection method of the present invention to clearly determine the arrival of the position.

That is, it is possible to discriminate between the rearmost and the frontmost of the seat 18 without providing separate limit switches, so that the limit switch can be omitted and the number of parts can be reduced, thereby simplifying the structure. To be done.

By the way, as shown in FIG. 1, in the position detecting method of the power seat of the present invention, a magnetic material is used.
The magnetic pole width W2 of 14 is formed to be the same as the arrangement pitch W1 of the reed switches 12. For example, if the position of the magnetic body 14 is close to the nth reed switch 12 from the rearmost, that is, the reed switch 12-n, and the total number of reed switches is S, the output voltage Eo (n) is It is shown in Equation 3 below.

[0041]

[Equation 3] Eo (n) = {n-R / (S + 1) R} E = {n / (S + 1)} E = {n-S / (S + 1) S} E

Next, the nth reed switch 12-n and the (n + 1) th reed switch next to the front side
If there is a magnetic substance 14 between 12- (n + 1),
The output voltage Eo (n +) is shown in the following Equation 4.

[0043]

[Equation 4] Eo (n +) = [{n ・ R / {(S + 1) -1} R] E ＝ (n / S) E ＝ {(n ・ S + n) / (S + 1) S } E

Furthermore, the nth reed switch 12-n and the (n-1) th reed switch 12- (n-
The output voltage Eo (n-) in the case where the magnetic substance 14 is present between 1) and is shown in the following Equation 5.

[0045]

[Equation 5] Eo (n-) = [{(n-1) R / {(S + 1) -1} R] E = {(n-1) / S} E = [{(n-1) (S + 1)} / (S + 1) S] E ＝ [{n (S + 1)-(S + 1)} / (S + 1) S] E ＝ [{nS + (nS-1)} / (S + 1) S] E

These equations satisfy n ≦ S and
As is clear from the comparison, since the denominators are common, Eo (n +)> Eo (n)>
It can be seen that the relationship of Eo (n-) holds. That is, the magnetic body
A reversing phenomenon that reverses the magnitude of the output voltage Eo even if the upper rail 20 stops with respect to the lower rail 24 with 14 being positioned between any of the reed switches 12 (12-1 to 12-10). Therefore, the position of the seat 18 can be accurately detected by the output voltage Eo corresponding to the position of the magnetic body.

In such a structure, the resistor
34 (34-1 to 34-11) and reed switch 12 (12-1 to
The same standard can be used as 12-10).
In this way, if resistors 34 (34-1 to 34-11) and reed switches 12 (12-1 to 12-10) of the same standard are used, in addition to simplifying the configuration, Since the assembling work is simplified, the overall cost reduction can be expected.

Further, in the embodiment, a reed switch is used.
Although 12 (12-1 to 12-10) are fixed to the upper rail 20 and the magnetic body 14 is fixed to the lower rail 24, it is sufficient if one of them is movable with respect to the other. The reed switch may be fixed to the lower rail and the magnetic body may be fixed to the upper rail.

Furthermore, in the embodiment, the structure of the power slide 16 in which the seat 18 is a movable member is embodied, but the present invention is not limited to this, and a reclining device in which a seat back is a movable member and a tilt angle of the seat are used. The position detection device 10 may be attached to a tilt device or the like for adjusting the position.

Although it is suitable for a power seat to be mounted on an automobile, a power seat is sufficient,
It is needless to say that the position detecting device of the present invention can be sufficiently used for a seat for trains, airplanes, ships and the like, bean jam, hairdressing, etc. without being limited thereto.

The above-mentioned embodiments are for explaining the present invention and do not limit the present invention in any way.
It goes without saying that the present invention includes all those which are modified or modified within the technical scope of the present invention.

[0052]

As described above, according to the position detecting method of the power seat of the present invention, the movable member from the base point is measured by the so-called external measurement method, which directly measures the moving amount of the movable member with respect to the fixed member. Since the moving distance is detected, the absolute position of the movable member can be easily detected from the base point.

Since the position of the movable member from the base point is directly detected under the ON operation of the reed switch, it is possible to reliably prevent mechanical accumulation of errors on the data.

Furthermore, since the position of the movable member can be digitally detected under the monitoring of the output voltage, the A / D converter is not required and the structure of the motor control device can be sufficiently simplified.

Further, according to the position detecting device for a power seat of the present invention, the above method can be appropriately performed, and therefore, without using an analog potentiometer,
The absolute position of the movable member can be easily detected. Further, since the reed switch and the magnetic material can be combined to form a non-contact type, a position detecting device having excellent durability can be secured.

If at least one of the resistor and the reed switch of the same standard is used, the assembly work is simplified in addition to the simplification of the structure, and the overall cost is sufficiently reduced. Can be expected.

Further, according to the arrangement holes of the printed circuit board,
If a series of reed switches are respectively arranged, the thickness of the reed switch is absorbed in the arrangement hole, so that so-called floating of the reed switch with respect to the printed circuit board can be prevented. Therefore, the reed switch can be easily made uniform in distance to the magnetic body, and an error in sensing the magnetic force from the magnetic body can be sufficiently prevented.

[Brief description of drawings]

FIG. 1 is a schematic exploded perspective view of a position detecting device for a power seat according to the present invention.

FIG. 2 is a schematic vertical sectional view of a position detecting device for a power seat.

FIG. 3 is a schematic side view of a power seat.

FIG. 4 is a schematic circuit diagram of a power seat position detection device.

FIG. 5 is a characteristic diagram showing the relationship between the position of the movable member and the output voltage in the position detecting method for the power seat of the present invention.

[Explanation of symbols]

 10 Power seat position detector 12 (12-1 to 12-10) Reed switch 14 Magnetic material 16 Power slide 20 Upper rail 24 Lower rail 34 (34-1 to 34-11) Resistor 44 Arrangement hole

Claims (4)

[Claims] 1. A corresponding number of reed switches are respectively branched and connected between a plurality of resistors of a series circuit to form a branch circuit for the series circuit, and the output voltage of the branch circuit is changed at the output end of the branch circuit. In addition to monitoring, a series of reed switches and a magnetic body arranged adjacent to each other are fixed to a fixed member and a movable member respectively, and one of the reed switch and the magnetic body is moved under the movement of the movable member with respect to the fixed member. Of the power sheet that detects the position of the movable member with respect to the fixed member from the position of the reed switch by distinguishing the reed switch that has been turned on by the proximity of the magnetic material from the output voltage from the branch circuit. Position detection method. 2. A plurality of reed switches, one end of which is connected to the other end of the reed switch, respectively, are connected between resistors of a series circuit composed of resistors one more than the number of reed switches,
A branch circuit for the series circuit of resistors is formed, and the series of reed switches is fixed at a specific pitch at equal intervals and fixed to either a fixed member or a movable member. A magnetic body having the same magnetic pole width as that of the fixed member and the movable member so that the magnetic body can move along the arrangement direction of the reed switch at a position close to the reed switch. The position detection device of the power seat that can determine the position of the reed switch that has been turned on by monitoring the output voltage from the output end of the branch circuit of the reed switch. 3. The position detecting device for a power seat according to claim 2, wherein at least one of the plurality of resistors and the plurality of reed switches of the same standard is used. 4. The position detecting device for a power seat according to claim 2, wherein the reed switch is a printed circuit board having an arrangement hole, and the thickness is absorbed by the arrangement hole.