Power assist steering system

• US 6,016,886 A
• Filed: 09/24/1997
• Issued: 01/25/2000
• Est. Priority Date: 07/25/1997
• Status: Expired due to Fees

• Current Assignee: Mtd Products Incorporated (Stanley Black & Decker, Inc.)
• Original Assignee: Mtd Products Incorporated (Stanley Black & Decker, Inc.)
• Inventors: Robertson, John, Schaedler, Axel
• Primary Examiner(s): Swann, J. J.
• Assistant Examiner(s): Ririe, Andrew J.
• Application Number:
  US08/936,372
• Time in Patent Office: 853 Days
• Field of Search: 180/400, 180/417, 180/432, 180/431, 180/439, 280/93.502, 280/93.507, 280/93.513
• US Class Current: 180/431
• CPC Class Codes: A01D 2101/00 Lawn-mowers
• CPC Class Codes: A01D 34/63 having cutters rotating about a vertical axis
• CPC Class Codes: B62D 5/06 fluid, i.e. using a pressurised fluid for most or all the force required for steering a vehicle
• CPC Class Codes: B62D 5/083 Rotary valves
• CPC Class Codes: B62D 5/16 Expansible chamber with flexible wall

Abstract

A power assist steering system is provided for use on a vehicle that has a steering implement and a steering mechanism operatively connected to a first wheel. The power assist steering system includes first and second vacuum actuators, a vacuum for providing a vacuum to the first and second vacuum actuators, an actuator for selectively activating the first and second vacuum actuators and a power assist for assisting the steering mechanism in turning the first wheel in first and second directions.

Claims

1. A power assist steering system for use on a riding mower, the riding mower having an engine with an intake manifold, a steering implement and a steering mechanism operatively connected to a first wheel, said power assist steering system comprising:

(1) first and second vacuum actuators each having

(a) a connection port and

(b) a first side, said first side of said first vacuum actuator moving inwardly with respect to said first vacuum actuator as a vacuum is established inside said first vacuum actuator and moving outwardly with respect to said first vacuum actuator as the vacuum is removed from inside said first vacuum actuator, said first side of said second vacuum actuator moving inwardly with respect to said second vacuum actuator as a vacuum is established inside said second vacuum actuator and moving outwardly with respect to said second vacuum actuator as the vacuum is removed from inside said second vacuum actuator;

(2) vacuum means for providing a vacuum to said first and second vacuum actuators, the intake manifold providing said vacuum means;

(3) activating means for selectively activating said first and second vacuum actuators, said activating means having

(a) first and second switching means, said first switching means selectively initiating said first vacuum actuator, said second switching means selectively initiating said second vacuum actuator,

(b) a vacuum source line, said vacuum source line communicating a vacuum from the intake manifold to said first and second switching means,

(c) first and second vacuum lines, said first vacuum line communicating a vacuum from said first switching means to said first vacuum actuator, said second vacuum line communicating a vacuum from said second switching means to said second vacuum actuator,

(d) a trigger segment having an extension with first and second ends, said trigger segment being selectively rotatable by the steering implement, said first end of said extension for selectively switching said first switching means, said second end of said extension for selectively switching said second switching means; and

,

(4) power assist means for assisting the steering mechanism, said power assist means having

(a) a first connector link for use in turning the first wheel in a first direction, said first connector link being operatively connected to said first side of said first vacuum actuator,

(b) a second connector link for use in turning the first wheel in a second direction, said second connector link being operatively connected to said first side of said second vacuum actuator,

(c) a valve plate having first and second sides for supporting said first and second switching means, said valve plate being operatively connected to the steering mechanism, said valve plate having first and second stop bars for operative connection with said first and second ends of said extension of said trigger segment, said first connector link being pivotably connected to said first side of said valve plate, said second connector link being pivotably connected to said second side of said valve plate.

2. A power assist steering system for use on a vehicle, the vehicle having a steering implement and a steering mechanism operatively connected to a first wheel, said power assist steering system comprising:

a first vacuum actuator;

vacuum means for providing a vacuum to said first vacuum actuator;

activating means for selectively activating said first vacuum actuator, said activating means including first switching means, said first switching means selectively initiating said first vacuum actuator, said activating means also including a trigger segment, said trigger segment being operatively connected to the steering implement, said trigger segment selectively switching said first switching means; and

,

power assist means for assisting the steering mechanism in turning the first wheel, said power assist means being operatively connected to said first vacuum actuator, said power assist means including a valve plate for supporting said first switching means, said valve plate being operatively connected to said trigger segment and the steering mechanism.

3. The power assist steering system of claim 2 wherein the vehicle has an engine with an intake manifold, said intake manifold providing said vacuum means.

4. The power assist steering system of claim 2 wherein said first switching means comprises:

a first air valve.

5. The power assist steering system of claim 2 wherein said first switching means comprises:

a first electric switch.

6. The power assist steering system of claim 2 wherein said trigger segment comprises:

an extension with first and second ends, said first end of said extension for selectively switching said first switching means.

7. A power assist steering system for use on a vehicle, the vehicle having a steering implement and a steering mechanism operatively connected to a first wheel, said power assist steering system comprising:

first and second vacuum actuators;

vacuum means for providing a vacuum to said first and second vacuum actuators;

activating means for selectively activating said first and second vacuum actuators, said activating means including first and second switching means and a trigger segment that is operatively connected to the steering implement, said first switching means selectively initiating said first vacuum actuator said second switching means selectively initiating said second vacuum actuator, said trigger segment selectively switching said first and second switching means, said trigger segment including an extension with first and second ends, said first end of said extension for selectively switching said first switching means, said second end of said extension for selectively switching said second switching means; and

,

power assist means for assisting the steering mechanism in turning the first wheel, said first vacuum actuator for use with said power assist means in turning the first wheel in a first direction, said second vacuum actuator for use with said power assist means in turning the first wheel in a second direction, said power assist means including a valve plate for supporting said first and second switching means, said valve plate being operatively connected to the steering mechanism, said valve plate having first and second stop bars for operative connection with said first and second ends of said extension of said trigger segment.

8. The power assist steering system of claim 7 wherein said first and second switching means comprise:

first and second air valves.

9. The power assist steering system of claim 7 wherein said first and second switching means comprise:

first and second electric switches.