Safety device for power windows

• US 6,347,482 B1
• Filed: 03/23/2000
• Issued: 02/19/2002
• Est. Priority Date: 03/23/1999
• Status: Expired due to Fees

• Current Assignee: Koito Manufacturing Company Limited
• Original Assignee: Koito Manufacturing Company Limited
• Inventors: Tajima, Keiichi, Takiguchi, Tsutomu, Fukazawa, Fusao
• Primary Examiner(s): Cohen, Curtis A.
• Application Number:
  US09/533,661
• Time in Patent Office: 698 Days
• Field of Search: 49/26, 49/27, 49/28, 318/283, 318/284, 318/466, 318/467, 318/468, 318/469
• US Class Current: 49/28
• CPC Class Codes: E05F 15/41 Detection by monitoring transmitted force or torque E05F15/48 takes precedence; Safety couplings with activation dependent upon torque or force, e.g. slip couplings
• CPC Class Codes: E05F 15/697 Motor units therefor, e.g. geared motors
• CPC Class Codes: E05Y 2400/326 of the angular type
• CPC Class Codes: E05Y 2600/458 in or on a transmission member
• CPC Class Codes: E05Y 2800/00 Details, accessories and auxiliary operations not otherwise provided for
• CPC Class Codes: E05Y 2900/55 Windows
• CPC Class Codes: H02H 1/0007 concerning the detecting means in general G01R or other subclasses of G01; reed switches H01H71/2445
• CPC Class Codes: H02H 7/0851 for motors actuating a movable member between two end positions, e.g. detecting an end position or obstruction by overload signal
• CPC Class Codes: H02H 7/093 against increase beyond, or decrease below, a predetermined level of rotational speed centrifugal switches H01H35/10

Abstract

A safety device for accurately preventing the catching of a hand or neck of a passenger of a vehicle between a windowpane and a window sash uses a potentiosensor 20 for detecting the rotational angular position of an output shaft adapted to rotate at a slower speed by reducing the speed of a rotating shaft of a driving motor 9 for opening and closing a windowpane of a vehicle with a speed reducing mechanism 10. This potentiosensor 20 comprises a resistance track plate 21 on which circular resistance track 25a and conductor tracks 25b, 25c are formed, and a rotating plate 23 having conductive brushes 24a, 24b adapted to slide over the resistance track plate 21. The windowpane position is detected based on a resistance value outputted when the conductive brushes 24a, 24b are rotationally moved on the resistance track 25a in response to the rotating position of the rotating plate 23. The resistance track 25a is supplied with a higher voltage and a lower voltage at diametrically opposite positions, respectively, and the conductive brushes 24a, 24b are constructed so as to output voltages which are divided at a rotating angle of 180 degrees. This enables not only the detection of the windowpane with high accuracy but also the miniaturization of a power window apparatus and simplification of the construction of a circuit thereof.

Claims

1. A safety device for power windows in which a driving motor is operated to open and close a windowpane of a vehicle, and in which the position of the windowpane is detected so as to safely control catching of a foreign object between the windowpane and a window frame, comprising:

a position sensor for detecting a rotational angular position of the driving motor;

means for detecting the position of the windowpane based on an output from said position sensor; and

means for safely controlling catching of a foreign object in the window-pane and the window frame based on an output of said position detecting means,

wherein said position sensor is a potentiosensor, said potentiosensor comprising;

a resistance track comprising a circular electric resistor pattern; and

conductive brushes rotating relative to said resistance track as the driving motor is driven and contacting said resistance track,

wherein said resistance track includes electrodes at two diametrically opposed points on the circumference of said resistance track, and

further wherein movement of each one of said conductive brushes results in a division of resistance between said electrodes.

2. A safety device for power windows as set forth in claim 1, wherein a higher electric potential is supplied to one of said electrodes of said resistance track, while a lower electric potential is supplied to the other electrode, and said division of resistance is between said higher electric potential and said lower electric potential.

3. A safety device for power windows as set forth in claim 2,

wherein said conductive brushes comprise a first conductive brush and a second conductive brush that are separated by 90 degrees in a rotational direction along said circular electric resistor pattern, and

further wherein said potentiosensor outputs a first signal corresponding to the movement of said first conductive brush and the driving motor and a second signal, which is out of phase with said first signal, corresponding to the movement of said second conductive brush and the driving motor.