JPH02114018A - Optical obstacle detecting device - Google Patents

Abstract

PURPOSE:To prevent the breakage of a door by providing a means switching the detection distance from the door at which an object can be detected and a means issuing an alarm when an obstacle for opening the door is detected in an obstacle detecting device optically detecting the object existing outside the door of a car. CONSTITUTION:When a driver moves a hand 21 near a key hole to perform the key operation from the outside while a door lever switch 14 is in the off state, a lighting means 16 is lit to illuminate the key hole based on the output of an obstacle detecting means constituted of a light emitting element 5 and a light receiving element 6. When a door lever is operated and the door lever switch 14 is turned on, a timer circuit 13 is operated, the comparison level of a variable-level comparator 9 is changed, the detection distance L is increased from about 5cm so far to about 20cm for better sensitivity, and a transfer switch 12 is switched to a warning means 17 side. When a door is to be opened from the inside during this time, if there is an obstacle within the range of about 20cm from the door and it is detected, a warning means 17 is operated.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to an optical obstacle detection device that optically detects objects existing outside the door of an automobile or the like.

(Prior art) When opening and closing the door of a car, etc., it is inconvenient that the keyhole cannot be seen when the surroundings are dark, such as at night.For this reason, it has been proposed to illuminate the keyhole when the door lever is touched, for example. This illumination of the keyhole allows the driver to easily open the door.Furthermore, the present invention proposes that the keyhole be illuminated even when a human hand approaches the door lever. This allows you to easily open the door without having to look for the door lever.

(Problem to be solved by the invention) By the way, when opening and closing the door as described above, there is no problem when opening the door from the outside, but when opening the door from the inside, if there is an obstacle on the outside, the door may hit the door. There was a problem with the door being damaged.

The present invention was made in view of these problems, and it is an object of the present invention to provide an optical obstacle detection device that can prevent damage to the door by detecting obstacles on the outside of the door in advance. It is an object.

[Means to solve the problem]

The optical obstacle detection device of the present invention is constructed as follows.

a) In an optical obstacle detection device that detects an object existing outside a door using a set of a light emitting element and a light receiving element, a switching means for switching a detection distance from the door at which the object can be detected; An alarm means is provided to issue an alarm when it detects the presence of an object that may be an obstacle when the door is opened.

b) In an optical obstacle detection device that detects an object existing outside a door using a set of light-emitting elements and light-receiving elements, a switching means for switching the detection distance from the door at which the object can be detected is provided, and a door lever is provided. Before operating the door, it detects the approach of a person's hand to the door and activates the keyhole lighting means.
After operating the door lever, the system detects any obstacles that may obstruct the opening of the door and activates an alarm.

C) In the optical obstacle detection device having the configuration a or b above, the detection distance is switched only for a certain period of time from when the door lever is operated.

d) In the optical obstacle detection device having any of the configurations a to C above, the signal light emitted from the light emitting element is an infrared modulated light emitted intermittently.

(Function) In the optical obstacle detection device of the present invention, by having the above configuration a or b, it is possible to detect an obstacle in advance when the door is opened and prevent damage to the door, and the configuration b This makes it easier to operate keys in dark places. Also,
By adopting the configurations C and d, power consumption can be reduced and the influence of ambient light can be removed.

〔Example〕

An embodiment of the present invention will be described below with reference to FIGS. 1 to 4.

FIG. 1 is a block diagram showing the circuit configuration of an optical obstacle detection device according to an embodiment of the present invention.

In the figure, 1 and 2 are OSCs (oscillators) that generate pulse signals with different cycles, 3 is an AND circuit, 4 is a light emitting amplifier for driving an LED (light emitting diode) 5, which is a light emitting element, and 6 is an LED 5. A PD (photodiode) is installed as a light-receiving element to receive the light reflected by the signal light from the object 7, and 8 amplifies the alternating current component (modulated signal component) in the signal converted into an electrical signal by the PD 6. 9 is a variable level comparator that compares the level of the amplified signal with a predetermined value, and the comparison level is variable. 10 is an AND circuit, 11 is a detector, and 12 is a changeover switch that is controlled by a timer circuit 13 together with the variable level comparator 9. The timer circuit 13 is activated by a signal from a door lever switch 14 attached to a car (not shown). . 15 is a one-shot multivibrator for illuminating the key hole of a car door for a certain period of time; 16
Reference numeral 17 indicates an illumination means, and 17 indicates an alarm means that issues an alarm when the presence of an object 7 that becomes an obstacle when the door is opened is detected.

FIG. 2 shows the arrangement positions of the LED 5 and PD 6 provided as the above-mentioned set of light emitting elements and light receiving elements.

Both LED5 and PD6 are placed near the keyhole 18 of the car door, and this keyhole! The above lighting means (
For example, an LED) 16 is provided. In the figure, 19 is a door lever.

The variable level comparator 9 shown in FIG. 1 above constitutes a switching means for switching the detection distance from the door at which the object 7 can be detected, and when the door lever 19 is operated, that is, the door lever switch 14 is turned on. Detection distance and changeover switch 12 only for a certain period of time set by the timer circuit 13
It is designed to switch between.

Next, the operation will be explained. Before operating the door lever 19, the approach of a person's hand (object 7) 21 holding a key 20 to the door is detected as shown in FIG. 3, and when the presence of the hand 21 is detected, the lighting means 16 is activated. to illuminate the keyhole 18.

Further, after the door lever 19 is operated, an obstacle (object 7) that becomes an obstacle when opening the door is detected, and when the obstacle is detected, the alarm means 17 is activated to notify the existence of the obstacle in advance.

That is, before the door lever 19 is operated, the door lever switch 14 is OFF and the detection distance #L shown in FIG. 3 is approximately 5 CflI.
For example, when the driver brings his/her hand 21 close to each other to perform a key operation from outside the vehicle, and the distance becomes about 5 cm, the key hole 18 is illuminated. Thereby, the driver can easily perform key operations without searching for the key hole 18.

Furthermore, by operating the door lever 19, the door lever switch 14 is turned on, and at this time the timer circuit 1
3 is activated, the comparison level of the variable level comparator 9 changes only for a few seconds to several tens of seconds, and the detection distance 11L changes to about 2.
The sensitivity is increased to about 0 cm, and the changeover switch 12 is switched to the alarm means 17 side. and,
During this time, when I tried to open the door from inside the car, I
If there is an obstacle within a range of about 0 cm, the alarm means 17 is activated and a buzzer etc. is used to notify the user of the presence of the obstacle in advance. Therefore, when exiting the vehicle in a parking lot or the like, the end of the door does not hit the wall or the body of another vehicle, and damage to the door can be prevented.

Here, a pair of LED 5 and PD 6 is used to detect the object 7 such as the human hand 21 or an obstacle.
The signal light emitted from 5 is an infrared modulated signal light that is emitted intermittently as shown in FIG. The frequency f of this infrared modulated light is set to several 100 Hz to several 10 Hz,
Further, the intermittent period T is set to be several hundred m5 or less, and one light emission time T2 is set to T1/(several 10 to several 10100). That is, the intermittent period T1 and the light emission time T2 are as follows:
This is set to suppress the overall light emission amount of the LED 5 and reduce current consumption. Considering the speed at which the human hand 21 approaches, the intermittent period T1 needs to be several hundred meters or less, and the light emission time T2 is To distinguish it from other modulated light, 10 times or more of (1/f), that is, T2/(1/f)≧
It is desirable to set it to 10. Therefore, the influence of ambient light is removed and power consumption is reduced. Furthermore, since the illumination means 16 is also operated only for a certain period of time, the power consumption is further reduced.

A signal of frequency f for emitting modulated light from the LED 5 is generated at osct in FIG. 1, and a timing signal of time T I, T * is generated at 03C2.

These signals then pass through an AND circuit 3 to become a signal as shown in FIG. 4, and this signal is suitably amplified by an AC amplifier 4 and supplied to an LED 5. Also, LED5
The signal light emitted from the object 7 and reflected by the object 7 is received by the PD 6 and converted into an electrical signal. The AC amplifier 8 amplifies only the AC component of this electrical signal.

Output to level comparator 9. The level comparator 9 selects signals above a certain level from the amplified signals and sends them to the AND circuit 10. Then, only the modulated signal is extracted by this AND circuit 10. This extracted signal becomes a DC signal in the detector 11, and operates the one-shot multivibrator 15. Then, the illumination means 16 is driven by this one-shot multivibrator 15, and the keyhole 18 is illuminated only once for a certain period of time as described above.

In the above embodiment, the detection distance 111L of the object 7 is switched by the variable level comparator 9, but the detection distance may also be switched by changing the amplification factor of the AC amplifier 8 in the preceding stage. .

Further, in order to reduce costs, the same light-emitting element, light-receiving element, and detection circuit are used for door keyhole illumination and obstacle alarm, but these may be provided separately.

〔Effect of the invention〕

As described above, according to the present invention, since the configuration includes the switching means for switching the object detection distance and the alarm means for notifying the presence of an obstacle, obstacles on the outside of the door can be detected in advance to prevent damage to the door. This has the effect of being able to prevent. In addition, by switching the detection distance only for a certain period of time after the door lever is operated and using infrared modulated light that is emitted intermittently, it is possible to reduce power consumption and eliminate the effects of ambient light. It will be done.

[Brief explanation of drawings]

1 to 4 are diagrams showing an optical obstacle detection device according to an embodiment of the present invention, FIG. 1 is a block diagram showing the circuit configuration, and FIG. 2 is a layout of the LED and PD shown in FIG. 1. A configuration diagram showing the position, Figure 3 is an explanatory diagram showing the object detection operation,
FIG. 4 is a waveform diagram showing the light emission mode of the LED. 5------LED (light emitting element) 6------PD (light receiving element) 7------Object 9---Variable level comparator (switching means) 12---All changeover switch 13- ------ Timer circuit 14 --- Door lever switch 16 --- Lighting means 17 --- Alarm means 18 --- Key hole 19 --- Door lever 20 -----Key 21---Single applicant Stanley Electric Co., Ltd.

Claims (4)

[Claims] (1) In an optical obstacle detection device that detects an object existing outside a door using a set of a light emitting element and a light receiving element, a switching means for switching a detection distance from the door at which the object can be detected; An optical obstacle detection device characterized by being provided with an alarm means that issues an alarm when the presence of an object that becomes an obstacle when opening a door is detected. (2) In an optical obstacle detection device that detects an object existing outside a door using a set of a light emitting element and a light receiving element, a switching means is provided for switching the detection distance from the door at which the object can be detected, Before operating the door lever, the system detects the approach of a person's hand to the door and activates the lighting means in the keyhole, and after operating the door lever, detects an obstacle that may obstruct opening the door and activates the alarm means. An optical obstacle detection device characterized by: (3) The optical obstacle detection device according to claim 1 or 2, characterized in that the detection distance is switched only for a certain period of time after the door lever is operated. (4) The optical obstacle detection device according to any one of claims 1 to 3, wherein the signal light emitted from the light emitting element is infrared modulated light that is emitted intermittently.