Sewing machine controller inhibiting sewing in unsafe conditions

• US 4,840,135 A
• Filed: 12/29/1987
• Issued: 06/20/1989
• Est. Priority Date: 12/03/1985
• Status: Expired due to Fees

• Current Assignee: Mitsubishi Denki Kabushiki Kaisha (Mitsubishi Electric Corporation)
• Original Assignee: Mitsubishi Denki Kabushiki Kaisha (Mitsubishi Electric Corporation)
• Inventors: Yamauchi, Satomi
• Primary Examiner(s): Nerbun, Peter
• Application Number:
  US07/165,824
• Time in Patent Office: 539 Days
• Field of Search: 112/237, 112/239, 112/277, 112/275, 112/121.11, 192/130
• US Class Current: 112/277
• CPC Class Codes: D05B 69/36 Devices for stopping drive when abnormal conditions occur, e.g. thread breakage
• CPC Class Codes: D05B 83/00 Guards or like devices for preventing injury to operator machine safety devices in general F16P
• CPC Class Codes: F16P 3/12 with means, e.g. feelers, which in case of the presence of a body part of a person in or near the danger zone influence the control or operation of the machine F16P3/08 takes precedence

Abstract

A sewing machine controller which inhibits compensation sewing if the cloth presser is raised, if the treadle switch is activated or a proximity switch mounted near the needle detects the operator'"'"'s hand.

Claims

1. A sewing machine controller having an automatic lifting mechanism for a cloth presser, comprising:

a first switch for controlling the rotation of a sewing machine motor shaft via a rotation command signal;

means for detecting conditions dangerous to an operator of said sewing machine;

means for inhibiting said rotation command signal responsive to an ouptut of said detecting means;

means for raising said cloth presser of said sewing machine;

said detecting means detecting a raising of said cloth presser;

a treadle switch; and

means for inhibiting said cloth presser raising means upon closure of said treadle switch.

2. A sewing machine controller having an automatic lifting mechanism for a cloth presser, comprising:

a controller;

a first AND gate;

a second AND gate;

an OR gate having its output connected to an input of said first AND gate;

an inverter having its output connected to an input of said OR gate and an input of said second AND gate;

a compensation sewing switch connected to another input of said first AND gate;

a cloth presser lifting switch connected to another input of said second AND gate;

a treadle switch connected to the input of said inverter;

a controller which receives the outputs of said first AND and said second AND gate;

a solenoid;

switch means;

wherein said controller supplies control signals to said solenoid through said switch means in response to the inputs from said first and second AND gates; and

said solenoid controls the lifting and downward moving operations of said cloth presser.

3. A sewing machine controller having an automatic lifting mechanism for a cloth presser, comprising:

first switch means for selectively delivering a first signal for placing said sewing machine in a first sewing mode;

second switch means for selectively delivering a second signal for placing said sewing machine in a second sewing mode;

means for generating a cloth presser raise signal for raising said cloth presser of said sewing machine; and

control means for controlling the operation of said sewing machine, said control means receiving said first signal, said second signal and said cloth presser raise signal;

said control means preventing said cloth presser from being raised when said second signal and said cloth presser raise signal are both present, and preventing said sewing machine from entering said first sewing mode when either of said cloth presser raise signal and said second signal is present.