JP2011175924A - Stop lamp switch for vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a stop lamp switch for a vehicle that can achieve space saving or reduction in cost and weight. <P>SOLUTION: The stop lamp switch for the vehicle includes: a magnetic body that moves in according with stepping in a brake pedal; and two or more magnetic detection parts that output a signal according to approach of the magnetic body, wherein the two or more magnetic detection part are provided on an element of one package. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a vehicle stop lamp switch that outputs a signal when a brake pedal is depressed.

  2. Description of the Related Art Conventionally, there is known a vehicle stop lamp switch that detects a position of a magnetic body that moves in conjunction with depression of a brake pedal by a magnetic detection unit and is used for lighting control of a stop lamp. Further, the output of the vehicle stop lamp switch can be used for other controls such as ACC (Adaptive Cruise Control) in addition to the stop lamp lighting control. The ACC includes constant speed traveling control and inter-vehicle distance control. In these controls, processing is performed to stop the control when the brake pedal is depressed more than a predetermined amount.

  In order to detect failures due to multiplexing and redundancy for such applications, it is desirable to prepare two or more types of output signals in a vehicle stop lamp switch.

  FIG. 1 is a diagram showing a configuration of a conventional vehicle stop lamp switch that can output two types of signals. As shown in the figure, the conventional vehicle stop lamp switch has two magnetoresistive elements, each of which has a power supply circuit and a magnetic detector mounted thereon. The outputs of the two magnetoresistive elements are supplied to a light ECU, an ACC ECU, or the like that controls lighting of the stop lamp. In the figure, S / L indicates a stop lamp control signal, and C / C indicates a cruise control cancel signal.

  Patent Document 1 describes a non-contact switch including two MR sensors (magnetoresistive sensors) configured to include a magnetoresistive element. In this switch, a plurality of separate MR sensors are arranged in a detection region in a plane orthogonal to a plane including a pair of extreme surfaces of a magnet having a substantially U shape.

JP 2009-16202 A

  However, in the structure having two or more sensors (magnetoresistance elements) as separate bodies, it is necessary to secure a mounting space on the board, so that the size of the switch becomes large, and interference with other components may occur. There is sex. This is because the space near the base of the brake pedal to which this type of switch is attached is greatly limited.

  Further, since two or more elements are used to prepare two or more types of output signals, the cost and weight are increased.

  The present invention is to solve such problems, and a main object of the present invention is to provide a vehicle stop lamp switch capable of realizing space saving and cost / weight reduction.

In order to achieve the above object, one embodiment of the present invention provides:
A magnetic body that moves in conjunction with the depression of the brake pedal,
Two or more magnetic detectors that output signals in response to the approach of the magnetic body;
A vehicle stop lamp switch comprising:
The two or more magnetic detection units are mounted on an element of one package,
This is a vehicle stop lamp switch.

  According to this aspect of the present invention, since two or more magnetic detectors are mounted on an element of one package, space saving and cost / weight reduction can be realized.

  Here, in addition to two or more magnetic detection units, a power supply circuit and the like are mounted on an element of one package.

In one embodiment of the present invention,
The two or more magnetic detection units are
A Lo signal is output when the magnetic body is at a position farther than the first predetermined position, and a Hi signal is output when the magnetic body is at a position closer to the first predetermined position. A magnetic detector of
A second signal that outputs a Hi signal when the magnetic body is at a position farther than a second predetermined position and outputs a Lo signal when the magnetic body is at a position closer to the second predetermined position. A magnetic detector of
It is good also as what is characterized by including.

in this case,
The timing at which the output signal of the first magnetic detection unit switches from the Lo signal to the Hi signal with the approach of the magnetic body is different from the timing at which the output signal of the second magnetic detection unit switches from the Hi signal to the Lo signal. It is good also as what is characterized by this.

  In this way, it is expected that a superposition period in which both the first magnetic detection unit and the second magnetic detection unit output a Hi signal is generated, and a switch failure can be easily detected based on the presence or absence of the superposition period. .

  ADVANTAGE OF THE INVENTION According to this invention, the stop lamp switch for vehicles which can implement | achieve space saving and reduction of cost and weight can be provided.

It is a figure which shows the structure of the conventional vehicle stop lamp switch which can output two types of signals. It is an example of composition of stop lamp switch 1 for vehicles concerning one example of the present invention. It is the side view which looked at the stop lamp switch 1 for vehicles which concerns on one Example of this invention from the X direction in FIG. 1 is a circuit block diagram of a vehicle stop lamp switch 1. FIG. It is a figure which shows the change of the output signal of the 1st magnetic detection part 40 and the 2nd magnetic detection part 42 according to the change of the depression amount of a brake pedal.

  DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments for carrying out the present invention will be described with reference to the accompanying drawings.

  Hereinafter, a stop lamp switch 1 for a vehicle according to an embodiment of the present invention will be described with reference to the drawings.

[Constitution]
FIG. 2 is a configuration example of a vehicle stop lamp switch 1 according to an embodiment of the present invention. The vehicle stop lamp switch 1 includes, as main components, a magnetic body 12 attached to a shaft 10 that moves in conjunction with depression of a brake pedal, and a magnetoresistive element 20 in one package attached on a substrate. Prepare.

  The shaft 10 moves to the right in the figure when the brake pedal is depressed, and moves to the left in the figure when the brake pedal is released and returned to its original position by a biasing spring or the like. The vehicle stop lamp switch 1 is configured to detect a change in magnetic flux caused by the shaft 10 moving in the right direction in the figure and output a signal.

  FIG. 3 is a side view of the vehicle stop lamp switch 1 according to one embodiment of the present invention as viewed from the X direction in FIG. As shown in the drawing, the vehicle stop lamp switch 1 can detect the depression of the brake pedal in a non-contact manner, and realizes improved durability.

  FIG. 4 is a circuit block diagram of the vehicle stop lamp switch 1. On the magnetoresistive element 20, a power control chip 30 including a power supply circuit and an AMP (Amplifier), a first magnetic detection unit 40, and a second magnetic detection unit 42 are mounted.

  The power control chip 30 is supplied with power from a + B power source and an IG power source. Here, the + B power supply means a power supply path that can supply power from the in-vehicle battery regardless of the ignition state, and the IG power supply means a power supply path that is supplied from the in-vehicle battery only when the ignition is on. ing.

  The power control chip 30 is supplied from the + B power source and / or the IG power source, amplifies the power, etc., and supplies the amplified power to the first magnetic detection unit 40 and the second magnetic detection unit 42. With such a configuration, the stop lamp can be lit even when the ignition is off.

  The first magnetic detection unit 40 and the second magnetic detection unit 42 each output a signal according to the approach of the magnetic body 12. As a result, two types of signals can be output from the vehicle stop lamp switch 1.

  Further, by mounting the first magnetic detection unit 40 and the second magnetic detection unit 42 on the magnetoresistive element 20 in one package, the size of the vehicle stop lamp switch 1 can be reduced. Interference with other parts can be suppressed. Furthermore, cost and weight can be reduced.

  Furthermore, by mounting the first magnetic detection unit 40 and the second magnetic detection unit 42 on the magnetoresistive element 20 in one package, the relative variation between the two types of output signals can be reduced, and the detection accuracy can be reduced. Can be improved. When mounting a magnetic detection unit on two or more elements configured as separate bodies, in addition to the mounting accuracy of the magnetic detection unit in the element, the mounting accuracy of the element on the substrate or the like causes a relative variation. However, in this embodiment, the factor can be narrowed down only to the mounting accuracy of the magnetic detection unit in the element.

[Change and use of output signal]
The first magnetic detection unit 40 and the second magnetic detection unit 42 include a magnetic sensing unit in which an electrical resistance value changes according to a change in the direction of the magnetic field, and when the change in the resistance value exceeds a threshold value The output signal is switched.

  When the magnetic body 12 approaches, the first magnetic detection unit 40 switches the output signal from the Lo signal to the Hi signal. Further, when the second magnetic detection unit 42 and the magnetic body 12 approach each other, the output signal is switched from the Hi signal to the Lo signal. The Lo signal is a voltage signal of 0 [V], for example, and the Hi signal is a voltage signal of 1 [V], for example.

  The output signal of the first magnetic detection unit 40 is output to a light ECU (Electronic Control Unit) 50.

  The light ECU 50 is, for example, a microcomputer in which a ROM (Read Only Memory), a RAM (Random Access Memory), and the like are connected to each other via a bus with a central processing unit (CPU) as a center. Drives, DVD-R (Digital Versatile Disk-Recordable) drives, CD-R (Compact Disc-Recordable) drives, EEPROM (Electronically Erasable and Programmable Read Only Memory) storage devices, I / O ports, timers, counters, etc. Is provided. The storage device stores programs and data executed by the CPU.

  When the Hi signal is input from the first magnetic detection unit 40, the light ECU 50 lights a stop lamp attached to the rear portion of the vehicle. In addition, the light ECU 50 controls the lighting of the tail lamp, the small lamp, and the headlight according to the operating state of a lighting switch (not shown), or automatically performs the lighting control according to the illuminance input from the conlight sensor. Or Specifically, when the illuminance input from the conlight sensor is equal to or lower than the reference illuminance, if the tail lamp and the small lamp are not turned on by a user operation, they are automatically turned on. When the illuminance input from the conlight sensor is lower, the tail lamp, small lamp and head lamp are automatically turned on.

  The output signal of the second magnetic detection unit 42 is output to an ECU 60 for ACC (Adaptive Cruise Control).

  The ACC ECU 60 is a microcomputer having the same configuration as the light ECU 50, for example, and is a control device for performing so-called constant speed traveling control and inter-vehicle distance control. The ACC ECU 60 is connected to a radar device and a camera for recognizing the inter-vehicle distance from the preceding vehicle, and maintains the inter-vehicle distance from the preceding vehicle at a preset target inter-vehicle distance, Controls the throttle motor and transmission. Further, when performing the constant speed traveling control, the throttle motor, the transmission, and the like are controlled so as to travel while maintaining a preset target vehicle speed.

  When the Lo signal is input from the second magnetic detection unit 42, the ACC ECU 60 cancels the constant speed traveling control and the inter-vehicle distance control. That is, when the brake pedal is depressed more than a predetermined amount, these controls are stopped.

  Note that the output signal of the first magnetic detection unit 40 may also be output to the ACC ECU 60. Similarly, the output signal of the second magnetic detection unit 42 may also be output to the light ECU 50. In this case, for example, these ECUs depress the brake pedal when the output signal of the first magnetic detection unit 40 is in the Hi state and the output signal of the second magnetic detection unit 42 is in the Lo state. Judge that Further, some step-by-step control may be performed using a shift in switching timing between the output signal of the first magnetic detection unit 40 and the output signal of the second magnetic detection unit 42.

  Here, as shown in FIG. 1, it is desirable that the first magnetic detection unit 40 and the second magnetic detection unit 42 be offset with respect to the direction in which the magnetic body 12 approaches. As a result, the switching points of the output signals of the first magnetic detection unit 40 and the second magnetic detection unit 42 are different.

  FIG. 5 is a diagram illustrating changes in output signals of the first magnetic detection unit 40 and the second magnetic detection unit 42 according to changes in the amount of depression of the brake pedal (position of the magnetic body 12). As shown in the drawing, the timing at which the output signal of the first magnetic detection unit 40 switches from the Lo signal to the Hi signal as the magnetic body 12 approaches, the output signal of the second magnetic detection unit 42 changes from the Hi signal to the Lo signal. It is faster than the timing of switching to.

  As a result, an overlapping period in which both the first magnetic detection unit 40 and the second magnetic detection unit 42 output the Hi signal occurs. Therefore, a switch failure can be easily detected based on the presence or absence of the superposition period. Note that such failure detection can be performed by communicating between ECUs, for example.

  According to the vehicle stop lamp switch 1 of the present embodiment described above, since the first magnetic detection unit 40 and the second magnetic detection unit 42 are mounted on the magnetoresistive element 20 of one package, the size is reduced. Thus, interference with other components can be suppressed. Furthermore, cost and weight can be reduced.

  That is, space saving and cost / weight reduction can be realized.

  Further, the relative variation between the two types of output signals can be reduced, and the detection accuracy can be improved.

  Furthermore, by mounting the first magnetic detection unit 40 and the second magnetic detection unit 42 so as to be offset with respect to the approaching direction of the magnetic body 12, the first magnetic detection unit 40 and the second magnetic detection unit 42 are mounted. The switching point of the output signal of the detector 42 is different, and a switch failure can be easily detected based on the presence or absence of the Hi signal superimposition period.

  The best mode for carrying out the present invention has been described above with reference to the embodiments. However, the present invention is not limited to these embodiments, and various modifications can be made without departing from the scope of the present invention. And substitutions can be added.

  For example, although two magnetic detection units are provided on the magnetoresistive element 20 of one package, three or more magnetic detection units may be provided.

  The offset relationship between the first magnetic detection unit 40 and the second magnetic detection unit 42 may be reversed. That is, as the magnetic body 12 approaches, the timing at which the output signal of the first magnetic detection unit 40 switches from the Lo signal to the Hi signal is the timing at which the output signal of the second magnetic detection unit 42 switches from the Hi signal to the Lo signal. It may be slower than

  Further, the control device or the like that uses the output signals of the first magnetic detection unit 40 and the second magnetic detection unit 42 is not limited to the light ECU 50 and the ACC ECU 60 mentioned in the embodiment, and any device can output signals. May be used. For example, a device that performs steering control, vehicle stabilization control, or the like may use the output signals of the first magnetic detection unit 40 and the second magnetic detection unit 42.

DESCRIPTION OF SYMBOLS 1 Vehicle stop lamp switch 10 Shaft 12 Magnetic body 20 Magnetoresistive element 30 Power control chip 40 1st magnetic detection part 42 2nd magnetic detection part 50 Light ECU
60 ECU for ACC

Claims (3)

A magnetic body that moves in conjunction with the depression of the brake pedal,
Two or more magnetic detectors that output signals in response to the approach of the magnetic body;
A vehicle stop lamp switch comprising:
The two or more magnetic detection units are mounted on an element of one package,
Stop lamp switch for vehicles. The vehicle stop lamp switch according to claim 1,
The two or more magnetic detection units are
A Lo signal is output when the magnetic body is at a position farther than the first predetermined position, and a Hi signal is output when the magnetic body is at a position closer to the first predetermined position. A magnetic detector of
A second signal that outputs a Hi signal when the magnetic body is at a position farther than a second predetermined position and outputs a Lo signal when the magnetic body is at a position closer to the second predetermined position. A magnetic detector of
Including,
Stop lamp switch for vehicles. The vehicle stop lamp switch according to claim 2,
The timing at which the output signal of the first magnetic detection unit switches from the Lo signal to the Hi signal with the approach of the magnetic body is different from the timing at which the output signal of the second magnetic detection unit switches from the Hi signal to the Lo signal. It is characterized by
Stop lamp switch for vehicles.

Images