Drive control device for opening/closing member

• US 5,530,329 A
• Filed: 03/28/1995
• Issued: 06/25/1996
• Est. Priority Date: 03/31/1994
• Status: Expired due to Term

• Current Assignee: Mitsui Kinzoku Act Corporation (Mitsui Mining and Smelting Company Limited)
• Original Assignee: Ohi Seisakusho Co., Ltd. (Mitsui Mining and Smelting Company Limited)
• Inventors: Kawanobe, Osamu, Shigematsu, Kouichi
• Primary Examiner(s): Sircus, Brian
• Application Number:
  US08/411,881
• Time in Patent Office: 455 Days
• Field of Search: 318/256, 318/257, 318/264, 318/265, 318/266, 318/268, 318/272, 318/273, 318/275, 318/280, 318/283, 318/286, 318/452, 318/453, 318/454, 318/456, 318/457, 318/458, 318/459 , 318/461-469, 318/474-479, 49/26-28
• US Class Current: 318/469
• CPC Class Codes: H02H 3/44 responsive to the rate of change of electrical quantities
• 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

Abstract

A drive control device for an opening and closing member is active to optimally adjust a threshold level for pinch detection. Utilizing a speed sensor or the like, the closing speed of the opening/closing member is detected. The value of the closing speed is renewed in accordance with the closing position and stored in memory. Based on memorized data, a predicting circuit derives a future closing speed. To the predicted value there is added an allowed addition value, to permit a threshold level setting circuit to set an appropriate threshold for pinch detection. The allowed addition value is adjusted in accordance with the closing speed of the opening/closing member by a threshold level adjusting circuit.

Claims

1. A drive control device for controlling a driving mechanism active to move an opening and closing member in first and second directions, comprising:

resistance detecting means which outputs a closing resistance value which varies in accordance with a detected resistance acting against movement of said opening and closing member during moving operation thereof;

pinch detecting means, active to terminate moving operation of said opening and closing member when said closing resistance value detected by said resistance detecting means exceeds a predetermined threshold level; and

threshold control means which varies said threshold level in accordance with a moving speed of said opening and closing member.

2. A drive control device for an opening and closing member as set forth in claim 1, further including position detecting means, said threshold control varying said threshold level in accordance with a moving speed and position of said opening and closing member.

3. A drive control device for an opening and closing member as set forth in claim 2, further including monitoring means which detects whether or not said opening and closing member is positioned within a predetermined monitoring zone so as to activate said pinch detecting means, said pinch detecting means operable only when said opening and closing member is positioned within said pinch monitoring zone.

4. A drive control device for an opening and closing member as set forth in claim 3, wherein said predetermined monitoring zone includes a position proximate terminal positions of movement of said opening and closing member in said first and second directions.

5. A drive control device for an opening and closing member as set forth in claim 1, wherein said drive control device is active only when said opening and closing member is driven said first direction which is established to be a closing direction thereof.

6. A drive control device for an opening and closing member as set forth in claim 1, wherein said drive control device is active only when said opening and closing member is driven in said second direction which is established to be an opening direction thereof.

7. A drive control device for an opening and closing member as set forth in claim 1, wherein said pinch detecting means further comprises:

first pinch detecting means active to repeatedly issue an abnormal condition signal when a closing resistance detected by said resistance detecting means exceeds a predetermined first threshold level; and

second pinch detecting means active to stop movement of said opening and closing member when a number of successive outputs of said abnormal condition detecting signal exceeds a second threshold level;

and wherein said threshold level adjusting means is active to vary said second threshold level in accordance with said moving speed of said opening and closing member.

8. A drive control device for an opening and closing member as set forth in claim 1, further including:

p1 memory means which memorizes respective resistance representing values output at a plurality of positions along the path of motion of said opening and closing member;

predicting means which predicts a future change of the resistance representing value based on current position, direction of movement and a currently detected resistance representing value of said opening and closing member and said resistance representing values memorized in said memory means and outputting a predicted resistance representing value signal;

threshold setting means which sets a threshold level for carrying out pinch detection by adding an allowed additional value to the predicted resistance representing value output by said predicting means,;

pinch detecting means which stops said movement of said opening and closing member when the resistance representing value detected by said resistance detecting means exceeds said threshold level; and

threshold level control means which controls said allowed additional value in accordance with said moving speed of said opening and closing member.

9. A drive control device for an opening and closing member as set forth in claim 1, further including:

memory means which memorizes said resistance representing value output by said resistance detecting means;

predicting means which outputs a predicted resistance representing value based on a currently detected resistance representing value and said resistance representing value memorized in said memory means;

threshold level setting means which sets a first threshold level for carrying out pinch detection operation based on said predicted resistance representing value;

first pinch detecting means which repeatedly issues an abnormal condition detecting signal when a resistance representing value detected by said resistance detecting means exceeds said first threshold level;

second pinch detecting means active to stop movement of said opening and closing member when a number of successive outputs of said abnormal condition detecting signal exceeds a second threshold level; and

threshold level control means which varies said second threshold level in accordance with said moving speed of said opening and closing member.

10. A drive control device for an opening and closing member as set forth in claim 1, wherein said resistance representing value is determined on the basis of one of:

a detected moving speed of said opening and closing member; and

a detected drive current of an electric motor by which movement of the opening and closing member is effected.