Vacuum actuated control mechanism

• US 5,911,672 A
• Filed: 12/19/1997
• Issued: 06/15/1999
• 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): Will, Thomas B.
• Assistant Examiner(s): FABIAN-KOVACS, ARPAD
• Application Number:
  US08/994,665
• Time in Patent Office: 543 Days
• Field of Search: 56/17.1, 56/17.2, 56/11.1, 56/11.7, 56/10.9, 91/454, 91/462, 91/465, 91/456, 91/448, 91/444
• US Class Current: 56/16.9
• CPC Class Codes: A01D 2101/00 Lawn-mowers
• CPC Class Codes: A01D 34/63 having cutters rotating about a vertical axis
• CPC Class Codes: A01D 34/64 mounted on a vehicle, e.g. a tractor, or drawn by an animal or a vehicle A01D34/695 takes precedence
• CPC Class Codes: A01D 34/69 with motor driven wheels
• CPC Class Codes: A01D 34/74 Cutting-height adjustment
• CPC Class Codes: A01D 43/0631 Control devices specially adapted therefor
• 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 riding lawn mower is provided that has an engine, a device that requires control and a vacuum actuated control mechanism for controlling the device. The vacuum actuated control mechanism includes a vacuum actuator having first and second chambers separated by a movable membrane, first connecting means for operatively connecting the vacuum actuator to the device, vacuum means for providing a vacuum to the vacuum actuator, activating means for selectively activating the vacuum actuator and securing means for securing the vacuum actuator in place. The securing means also secures the device in place.

Claims

1. A mower comprising:

a frame;

cutting blades operatively mounted to said frame;

an engine operatively mounted to said frame;

a device that requires control; and

,

a vacuum actuated control mechanism for controlling said device, said vacuum actuated control mechanism including,

1) a first vacuum actuator having a movable membrane;

2) first connecting means for operatively connecting said movable membrane to said device;

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

4) activating means for selectively activating said first vacuum actuator; and

,

5) securing means for selectively securing said moveable membrane in place thereby selectively securing said device in place.

2. The mower of claim 1 wherein said movable membrane separates said first vacuum actuator into first and second chambers, said activating means comprising:

first and second switching means for selectively permitting airflow between said first and second chambers and said vacuum means;

a rocking switch for selectively activating said first and second switching means; and

,

vacuum lines for communicating said vacuum means to said first and second switching means and for communicating said first and second switching means to said first and second chambers respectively.

3. The mower of claim 2 wherein said securing means comprises:

third and fourth switching means for selectively permitting airflow between said first and second chambers and said first and second switching means respectively, said rocking switch selectively activating said third and fourth switching means.

4. A mower comprising:

an engine;

a mower deck having cutting blades;

a lift assembly for use in lifting said mower deck; and

,

a vacuum actuated control mechanism for controlling the height of said mower deck, said vacuum actuated control mechanism including,

1) a first vacuum actuator,

2) first connecting means for operatively connecting said first vacuum actuator to said lift assembly,

3) vacuum means for providing a vacuum to said first vacuum actuator,

4) activating means for selectively activating said first vacuum actuator and,

5) securing means for securing said first vacuum actuator in place thereby securing said mower deck at a selected height.

5. The mower of claim 4 wherein said first vacuum actuator has first and second chambers separated by a movable membrane,

said activating means including,

(1) first and second switching means for selectively permitting airflow between said first and second chambers and said vacuum means,

(2) a rocking switch for selectively activating said first and second switching means and,

(3) vacuum lines for communicating said vacuum means to said first and second switching means and for communicating said first and second switching means to said first and second chambers respectively,

said securing means including,

(1) third and fourth switching means for selectively permitting airflow between said first and second chambers and said first and second switching means respectively, said rocking switch selectively activating said third and fourth switching means.

6. The mower of claim 4 wherein said mower has a frame, said lift assembly comprising:

a deck shaft, said deck shaft being rotatably connected to said frame, said deck shaft being operatively connected to said mower deck; and

,

a vacuum lift arm, said vacuum lift arm being fixedly attached to said deck shaft, said first vacuum lift arm being operatively connected to said first connecting means.

7. The mower of claim 4 wherein said rocking switch comprises:

first and second inner rocking switches, said first inner rocking switch selectively activating said first, third and fourth switching means, said second inner rocking switch selectively activating said second, third and fourth switching means; and

,

a rocking button, said rocking button selectively activating said first and second inner rocking switches.

8. A method for controlling the height of a mower deck comprising the steps of:

providing a mower having an engine, a mower deck having cutting blades, and a lift assembly for use in lifting the mower deck;

providing a vacuum actuator having first and second chambers separated by a moveable membrane into operative connection with the lift assembly and with the mower;

removing a vacuum from the first chamber of the vacuum actuator;

establishing a vacuum within the second chamber of the vacuum actuator; and

,

adjusting the height of the mower deck.

9. The method of claim 8 wherein, after the step of adjusting the height of the mower deck, the method comprises the step of:

securing the moveable membrane in place thereby securing the mower deck at a selected height.

10. The method of claim 8 wherein, before the step of removing a vacuum from the first chamber of the vacuum actuator, the method comprises the steps of:

providing a first valve used to communicate a vacuum source to the first chamber, a second valve used to communicate the vacuum source to the second chamber, a third valve used to communicate the vacuum source from the first valve to the first chamber, and a forth valve used to communicate the vacuum source from the second valve to the second chamber;

switching a first switch;

activating the third valve thereby permitting airflow between the first chamber and the first valve;

activating the forth valve thereby permitting airflow between the second chamber and the second valve; and

,

activating the first valve thereby permitting ambient air to enter the first chamber.

11. The method of claim 10 wherein, after the step of adjusting the height of the mower deck, the method comprises the steps of:

releasing the first switch;

activating the third and fourth valves thereby preventing airflow between the first and second chambers and the first and second valves respectively; and

,

securing the moveable membrane in place thereby securing the mower deck at a selected height.

12. A mower comprising:

an engine;

cutting blades;

a drive axle, said drive axle providing locomotion for the mower;

a drive system, said drive system selectively transferring power from said engine to said drive axle; and

,

a vacuum actuated control mechanism for controlling the speed of the mower, said vacuum actuated control mechanism including,

1) a first vacuum actuator having a movable membrane;

2) first connecting means for operatively connecting said movable membrane to said drive system;

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

4) activating means for selectively activating said first vacuum actuator; and

,

5) securing means for selectively securing said moveable membrane in place thereby selectively securing a constant speed for said drive axle.

13. The mower of claim 12 wherein said movable membrane separates said first vacuum actuator into first and second chambers,

said activating means including,

(1) first and second switching means for selectively permitting airflow between said first and second chambers and said vacuum means,

(2) a rocking switch for selectively activating said first and second switching means and,

(3) vacuum lines for communicating said vacuum means to said first and second switching means and for communicating said first and second switching means to said first and second chambers respectively,

said securing means including,

(1) third and fourth switching means for selectively permitting airflow between said first and second chambers and said first and second switching means respectively, said rocking switch selectively activating said third and fourth switching means.

14. The mower of claim 13 wherein said drive system comprises:

a friction disk having a friction surface, said friction disk being rotatable by said engine;

a speed shaft, said speed shaft being operatively connected to said drive shaft; and

,

a friction ring having a friction edge, said friction edge for frictional contact with said friction surface of said friction disk, said friction ring selectively rotating said speed shaft, said friction ring selectively movable along said speed shaft, said friction ring being operatively connected to said first connecting means, said securing means also for securing said friction ring in place along said speed shaft.

15. The mower of claim 13 wherein said drive system comprises:

a double pulley;

a first belt operatively connecting said engine to said double pulley;

a second belt operatively connecting said double pulley to said drive axle;

a first idler pulley for use in maintaining the belt pressure of said first belt; and

,

a first idler lever operatively attached to said first idler pulley, said first idler lever selectively moving said first idler pulley, said first idler lever being operatively connected to said first connecting means, said securing means also for securing said first idler pulley in place against said first belt.

16. The mower of claim 13 wherein said drive system comprises:

a hydrostatic transmission operatively connected to said drive axle, said engine being operatively connected to said hydrostatic transmission; and

,

a hydrostatic lever operatively connected to said hydrostatic transmission, said hydrostatic lever being operatively connected to said first connecting means, said securing means also for securing said hydrostatic lever in place.

17. A method for controlling the speed of a mower comprising the steps of:

providing a mower having an engine, a mower deck having cutting blades, a drive axle for providing locomotion for the mower, and a drive system for selectively transferring power from the engine to the drive axle;

providing a vacuum actuator having first and second chambers separated by a moveable membrane into operative connection With the drive system and with the mower;

removing vacuum from the first chamber of the vacuum actuator;

establishing a vacuum within the second chamber of the vacuum actuator; and

,

adjusting the speed of the mower.

18. The method of claim 17 wherein, after the step of adjusting the speed of the mower, the method comprises the step of:

securing the moveable membrane in place thereby securing a constant speed for the mower.

19. The method of claim 17 wherein, before the step of removing vacuum from the first chamber of the vacuum actuator, the method comprises the steps of:

providing a first valve used to communicate a vacuum source to the first chamber, a second valve used to communicate the vacuum source to the second chamber, a third valve used to communicate the vacuum source from the first valve to the first chamber, and a forth valve used to communicate the vacuum source from the second valve to the second chamber;

switching a first switch;

activating the third valve thereby permitting airflow between the first chamber and the first valve;

activating the fourth valve thereby permitting airflow between the second chamber and the second valve; and

,

activating the first valve thereby permitting ambient air to enter the first chamber.

20. The method of claim 19 wherein, after the step of adjusting the speed of the mower, the method comprises the steps of:

releasing the first switch;

activating the third and fourth valves thereby preventing airflow between the first and second chambers and the first and second valves respectively; and

,

securing the vacuum actuator in place thereby securing a constant speed for the mower.