Radiant energy – Photocells; circuits and apparatus – Optical or pre-photocell system
Reexamination Certificate
1999-09-07
2002-07-16
Le, Que T. (Department: 2878)
Radiant energy
Photocells; circuits and apparatus
Optical or pre-photocell system
C250S227140, C049S025000
Reexamination Certificate
active
06420693
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a foreign object insertion detector device which is applied to a car power window device.
2. Description of the Related Prior Art
Conventionally, as a foreign object insertion detector device to be applied to a car power window device, there are known the following foreign object insertion detector devices.
That is, as a first conventional foreign object insertion detector device, there is known a foreign object insertion detector device which detects the insertion of a foreign object according to whether there is present an excess current or not which flows in a motor used to drive, that is, open and close the windowpane of a car window.
Also, as a second conventional foreign object insertion detector device, there is known a foreign object insertion detector device in which a soft tube body filled with transparent liquid of a high refractive index and formed of elastic material having a lower refractive index than that of the transparent liquid is implanted into a weather strip and, on both sides of the soft tube body in the longitudinal direction thereof, there are disposed a light emitting element and a light receiving element (Japanese Patent Publication No. 58-26621 of Showa). In the present insertion detector device, the light emitted from the light emitting element disposed on one end side is allowed to enter the transparent liquid serving as a core so that, while the light is being reflected totally by the inner peripheral surface of the soft tube body, the light is transmitted to the other end side and is received by the light receiving element; and, based on variations in the quantity of the light received by the light receiving element, the insertion of a foreign object can be detected.
In other words, in this conventional detector device, if there occurs any foreign object insertion and the soft tube body is elastically deformed due to a pressing force given from the foreign object, then the angle of incidence of the light entering the inner peripheral surface of the elastically deformed portion of the soft tube body varies; and, due to this, most of the light transmitted through the transparent liquid is changed in the advancing direction thereof and thus the light is caused to enter the inner peripheral surface of the soft tube body at the angle of incidence lower than or equal to a critical angle where the total reflection of the light occurs, with the result that the light is caused to leak outside the transparent liquid which serves as a guide path for the light. That is, the present detector device detects a decrease in the quantity of the received light of the light receiving element caused by the above-mentioned leakage of the light to thereby be able to detect the insertion of the foreign object.
However, in the above-mentioned first conventional foreign object insertion detector device, in order to prevent the foreign object insertion detector device from malfunctioning due to an excess current flowing in the motor when closing the windowpane tightly, the foreign object insertion preventive function of the detector device must be removed shortly before the windowpane is closed completely, with the result that the insertion preventive condition up to the time when the windowpane is closed completely cannot be secured positively.
Also, since the first conventional foreign object insertion detector device detects the insertion of a foreign object by detecting an excess current which is caused to flow when a load of a reference value or larger is applied to the motor, if the reference value is set too low, then there is a possibility that the presence of a foreign object insertion can be detected in error although no foreign object insertion exists actually. In order to prevent such erroneous detection, the reference value cannot be set excessively low. However, if the reference value is set rather high, then the detecting sensitivity is lowered accordingly. Therefore, when an operator's hand or the like is caught between the car window and the windowpane, a great force can be applied to the hand.
On the other hand, in the above-mentioned second conventional foreign object insertion detector device, since the transparent liquid must be enclosed into the soft tube body, the structure of the soft tube body is made complicated, which results in the expensive manufacturing cost of the soft tube body.
Also, in order to be able to detect the insertion of a foreign object before a great force from the motor is given to the foreign object, preferably, the soft tube body may be elastically deformed easily by a relatively small pressing force. However, in the second conventional foreign object insertion detector device, since the transparent liquid must be enclosed with a certain level of constant pressure, if the hardness of the soft tube body is set too low, then there is a possibility that the soft tube body can be caused to swell more than necessary or the soft tube body can be deformed due to the weight of the transparent liquid too much to keep its shape. Therefore, the soft tube body must be so set as to have hardness equal to or higher than a given level of hardness, which unfavorably results in the poor detecting sensitivity of the pressing force from the foreign object.
Further, since the soft tube body is structured such that it encloses the transparent liquid therein, there is no space for the internal pressure thereof to escape and thus, when the pressing force from the foreign object is applied to the soft tube body, the internal pressure of the soft tube body increases in proportion to an increase in the pressing force applied from the foreign object; that is, as the pressing force from the foreign object increases, the repulsive force of the soft tube body against the pressing force from the foreign object increases. Therefore, the soft tube body with the transparent liquid enclosed therein is difficult to deform when an external pressing force is applied thereto, which also provides a factor in lowering the detecting sensitivity of the pressing force from the foreign object.
Still further, there is also found a problem that it is difficult to keep the reliability of the sealed enclosure of the transparent liquid for a long period of time.
Yet further, when water is used as the transparent liquid, the water can be frozen depending on the using temperatures thereof, which causes the light to be scattered within the light guide path, with the result that the foreign object detector device using the water can fail to function.
In addition, normally, the elastic material that is used to form the soft tube body has a low degree of crystallinity in the using temperatures (−40° C.-+100° C). Therefore, the elastic material is easy to swell by the liquid that is enclosed in the soft tube body, or some of the elastic material is easy to deteriorate in quality.
SUMMARY OF THE INVENTION
The present invention aims at eliminating the drawbacks found in the above-mentioned conventional foreign object insertion detector devices. Accordingly, it is an object of the invention to provide a foreign object insertion detector device which is simple in structure, can be reduced in the manufacturing cost thereof, is highly reliable, is able to detect a pressing force from a foreign object with high sensitivity, and is also able to detect even the insertion of the foreign object occurring just before the windowpane is closed completely.
As technical means for attaining the above object, according to the invention, there is provided, for use in a car power window device in which a car window can be opened and closed as a windowpane is driven or opened and closed by a drive mechanism under the control of a given control part, a foreign object insertion detector device for detecting the insertion of a foreign object between the car window and the windowpane when the car window is closed by the windowpane, the foreign object insertion detector device comprising: a weather strip
Kamakura Mitsutoshi
Kume Masahiro
Matsumoto Yasuyo
Nakatsuji Naohiro
Toyozumi Morihiko
Autonetworks Technologies Ltd.
Le Que T.
Luu Thanh X.
Oliff & Berridg,e PLC
LandOfFree
Foreign object insertion detector device does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Foreign object insertion detector device, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Foreign object insertion detector device will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2835364