Control system for an automatic transmission testing device

• US 4,468,958 A
• Filed: 08/27/1982
• Issued: 09/04/1984
• Est. Priority Date: 08/31/1981
• Status: Expired due to Term

• Current Assignee: Mitsubishi Denki Kabushiki Kaisha (Mitsubishi Electric Corporation)
• Original Assignee: Mitsubishi Denki Kabushiki Kaisha (Mitsubishi Electric Corporation)
• Inventors: Takeshita, Hiroshi
• Primary Examiner(s): Goldberg, Gerald
• Assistant Examiner(s): Tumm, Brian
• Application Number:
  US06/412,099
• Time in Patent Office: 739 Days
• Field of Search: 73/118, 73/162, 73/862
• US Class Current: 73/115.02
• CPC Class Codes: F16H 61/12 Detecting malfunction or potential malfunction, e.g. fail safe in control of hydrostatic gearing F16H61/4192; Circumventing or fixing failures
• CPC Class Codes: G01M 13/025 Test-benches with rotational drive means and loading means; Load or drive simulation

Abstract

The present invention relates to a control system for a testing device for the automatic transmissions used in automobiles, and comprises a torque controlling feedback loop for controlling the torque applied to the input shaft of the transmission under test, and a speed controlling feedback loop for controlling the speed of the output shaft of the transmission under test, whereby the circumstances in an actual automobile application can be accurately and easily simulated to allow realistic testing of the automatic transmission.

Claims

1. A control system for a testing device for automatic transmissions, including a prime mover torque source to supply torque to the input shaft of an automatic transmission under test, and a simulated load to subject to load the output shaft of said automatic transmission, to simulate the operating conditions of an actual automobile, comprising:

an input shaft side torque controlling feedback loop including a torque reference signal producing means which provides a torque reference signal for controlling the torque applied to the input shaft of said test transmission by said prime mover torque source, a torque detector which produces an actual torque signal corresponding to the actual torque being applied to the input shaft of said test transmission by said prime mover torque source, and a torque computer which compares said torque reference signal and said actual torque signal to control the torque applied to said input shaft of said test transmission at a value determined by said torque reference signal producing means; and

an output shaft side speed controlling feedback loop including a speed reference signal producing means which provides a speed reference signal for controlling the speed of the output shaft of said test transmission by means of said simulated load, a speed detector which produces an actual speed signal corresponding to the actual speed of said output shaft of said test transmission, and a speed computer which compares said speed reference signal and said actual speed signal to control the speed of the output shaft of said test transmission by means of said simulated load, whereby the speed of the output shaft of said test transmission is maintained substantially constant at a gear shift point, in simulation of the actual circumstances of an actual automobile application, regardless of the change in speed of the prime mover torque source that results from the different gear ratios before and after the gear shift.