Rear window wiper motor control

• US 4,336,482 A
• Filed: 11/27/1979
• Issued: 06/22/1982
• Est. Priority Date: 11/30/1978
• Status: Expired due to Term

• Current Assignee: ITT Industries Inc (ITT, Inc.)
• Original Assignee: ITT Industries Inc (ITT, Inc.)
• Inventors: Prohaska, Hans, Goertler, Horst, Rachner, Horst, Munz, Joachim
• Primary Examiner(s): Weldon, Ulysses
• Application Number:
  US06/097,848
• Time in Patent Office: 938 Days
• Field of Search: 15/250.12, 15/250.02, 15/250.13, 15/250.14, 15/250.17, 318/443, 318/446, 318/256, 318/261, 318/280, 318/281, 318/282, 318/284, 318/444, 318/257, 318/258, 318/282
• US Class Current: 318/443
• CPC Class Codes: B60S 1/0814 using several drive motors; motor synchronisation circuits
• CPC Class Codes: B60S 1/482 combined with the operation of windscreen wipers
• CPC Class Codes: B60S 1/583 including wiping devices

Abstract

A windshield wiper system having an electric motor for driving windshield wipers through repeating wiper cycles by reversing the direction of rotation of the motor through a reversing switch comprising a pair of relays which control the polarity of current applied to the motor. A limit switch is mechanically coupled to the motor for detecting the end positions of the motor and for providing signals indicative thereof. First and second time delay circuits each have an output respectively coupled to one of the relays, and each delay circuit has a pair of inputs coupled to the limit switch. Each delay circuit is activated to provide a delayed output to its relay by a respective end position signal which immediately deactivates the other delay circuit.

Claims

1. In an windshield wiper system having a current-controlled electric motor for driving windshield wipers through repeating wiping cycles by reversing the direction of rotation of the motor through a reversing switch comprising a pair of relays which control the polarity of current applied to the motor, the improvement therewith comprising:

a limit switch mechanically coupled to said motor for detecting the end positions of said motor and for providing input signals indicative of said end positions; and

, first and second time delay circuits each having an output respectively coupled to one of said relays and each of said delay circuits having a pair of inputs coupled to said limit switch, the first input of each delay circuit being responsive to respective ones of said input signals to activate the output of the delay circuit after a predetermined delay period and the second input of each delay circuit being responsive to respective ones of said input signals to deactivate the output of the delay circuit upon the application of an input signal, with the first input of the first delay circuit and the second input of the second delay circuit being responsive to a first one of said input signals provided by said limit switch when said limit switch detects a first end position of said motor, and with the first input of the second delay circuit and the second input of the first delay circuit being responsive to a second one of said input signals provided by said limit switch when said limit switch detects the other end position of said motor.