INCHING VALVE WITH BYPASS VALVE FOR FILLING CLUTCHES

• US 3,715,017 A
• Filed: 10/30/1970
• Issued: 02/06/1973
• Est. Priority Date: 10/30/1970
• Status: Expired due to Term

• Current Assignee: Asa R. Jenney
• Original Assignee: Asa R. Jenney
• Inventors: Jenney, Asa R.
• Primary Examiner(s): Wyche, Benjamin W.
• Application Number:
  US05/085,537
• Time in Patent Office: 830 Days
• Field of Search: 192/4A,4C,13R,19F,85R,87.18,87.19
• US Class Current: 192/220
• CPC Class Codes: B60K 17/10 of fluid gearing of fluid clutches B60K17/02
• CPC Class Codes: B60W 10/10 including control of change-speed gearings
• CPC Class Codes: B60W 10/18 including control of braking systems
• CPC Class Codes: F16H 2312/10 Inching
• CPC Class Codes: F16H 61/0272 characterised by initiating reverse gearshift
• CPC Class Codes: Y10T 137/2615 Bypass or relief valve opens as other branch valve closes

Abstract

A system for controlling gradual engagement and disengagement of the forward and reverse clutches of a fluid power shifted transmission. The system includes a pump for supplying pressurized fluid to the clutches via a pressure regulating valve responsive to brake actuation and a clutch selector valve. Connected between the pump and selector valve is a normally open valve which bypasses the regulator valve and is operable to close when the pressure of fluid being supplied to the selector valve rises above a predetermined pressure.

Claims

1. For use with a vehicle having brakes and a transmission with first and second fluid actuated clutches, an inching system comprising a reservoir, a pump connected to said reservoir, a pressure regulating valve, first fluid conduit means connecting said pump and regulating valve, a clutch selector valve connected to the first and second clutches and said reservoir, second fluid conduit means connecting said selector valve to said regulating valve, said regulating valve being responsive to brake actuation and operable to decrease the pressure of fluid being supplied to said selector valve as brake actuation increases, said selector valve being operable to direct fluid to one of the clutches and communicate the other clutch with said reservoir and vice versa, and means connected to said first and second fluid conduit means for bypassing said regulating valve, the means for bypassing the regulating valve comprising an onoff valve connected between first and second fluid conduit means, said valve being normally open and operable to close when fluid pressure reaches a predetermined level in the second fluid conduit means.

2. For use with a vehicle having brakes and a transmission with a selector direction control valve and including first and second fluid actuated clutches, an inching system comprising a reservoir, a source of fluid under pressure, a pressure regulating inching valve, a first fluid conduit means connecting the pressure source and the inching valve, the clutch selector direction control valve connected to the first and second clutches and said reservoir, said selector direction control valve being operable to direct fluid to one of the fluid actuated clutches and communicate the other clutch with said reservoir and vice versa, second fluid conduit means connecting the inching valve and the selector direction control valve, said inching valve being responsive to brake actuation and operable to decrease the pressure of fluid being supplied to said selector direction control valve as brake actuation increases, the improvement comprising an on-off bypass valve connected between said first and second fluid conduit means to bypass said pressure regulating inching valve, said on-off bypass valve being normally open and operable to close when pressure reaches a predetermined level in the second fluid conduit means.