Park brake and control lever interlock for ZTR vehicle

• US 20060172857A1
• Filed: 01/10/2006
• Published: 08/03/2006
• Est. Priority Date: 01/18/2005
• Status: Active Grant

• Current Assignee: Mtd Products Incorporated (Stanley Black & Decker, Inc.)
• Original Assignee: Commercial Turf Products
• Inventors: Eavenson, Jimmy N. Sr., Buchanan, Peter
• Granted Patent: US 7,451,865 B2
• Time in Patent Office: Days
• US Class Current: 477/203
• 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: B60T 11/04 transmitting mechanically
• CPC Class Codes: B60T 7/10 Disposition of hand control
• CPC Class Codes: B62D 11/006 Mechanical control systems

Abstract

A ZTR lawnmower having and first and second drive wheels and first and second control levers to control the direction and speed of rotation of the first and second drive wheels. The lawnmower further includes a park brake system operatively interconnected with at least one of the drive wheels, and an interlock mechanism interfacing with the parking system. The park brake interlock mechanism includes a parking brake handle movable between an engaged position and a disengaged position to cause the park brake system to respectively resist and not resist rotation of the at least one drive wheel. The interlock mechanism interfaces with the park brake handle and the control levers such that when the first and second control levers are in the neutral position, the interlock mechanism permits the parking brake handle to be placed in the engaged position, and when the first and/or second control levers are not in the neutral position, the interlock mechanism prevents the parking brake handle from being placed in the engaged position.

Claims

1. A riding lawnmower comprising:

a chassis;

a power source;

first and second drive wheels at least partially supporting said chassis and rotatable via the power source to cause movement of said lawnmower;

first and second control levers associated with and controlling first and second drive systems, respectively, to control the direction and speed of rotation of said first and second drive wheels, respectively, each of said control levers having a neutral position in which the associated drive system does not cause rotation of the associated drive wheel;

a park brake system operatively interconnected with at least one of said drive wheels; and

an interlock mechanism interfacing with said parking system, said park brake interlock mechanism comprising a parking brake handle movable between an engaged position and a disengaged position to cause said park brake system to respectively resist and not resist rotation of said at least one drive wheel, said interlock mechanism interfacing said park brake handle and with said control levers such that when said first and second control levers are in said neutral position, said interlock mechanism permits said parking brake handle to be placed in said engaged position, and when said first and/or second control levers are not in said neutral position, said interlock mechanism prevents said parking brake handle from being placed in said engaged position.

2. The lawnmower of claim 1 wherein each of said control levers comprises a plate member having a notch therein, said notch being located such that when said control lever is in said neutral position, a portion of said interlock mechanism is received within said notch when the park brake handle is placed in said engaged position, and when said control lever is not in said neutral position, said interlock mechanism contacts the plate member and prevents the park brake handle from being placed in said engaged position.

3. The lawnmower of claim 2 wherein said park brake interlock mechanism comprises first and second interlock arms linked to said park brake handle, said interlock arms having respective portions configured to be received within said notches in said control plates.

4. The lawnmower of claim 3, further comprising a parking brake sensor configured to determine when said parking brake handle is in the engaged position, said sensor interfacing with a starting device for starting said power source, wherein said sensor prevents said starting device from starting said power source when said parking brake handle is not in said engaged position.

5. The lawnmower of claim 4, wherein said sensor does not directly determine whether said control levers are in said neutral positions.

6. The lawnmower of claim 4, wherein said parking brake sensor includes a plunger depressed by a finger on said brake handle in response to movement of said parking brake handle into said engaged position.

7. The lawnmower of claim 4, wherein the parking brake interlock mechanism is mounted to the chassis and further comprises a parking brake actuating handle and a brake actuating rod, and wherein each of the interlock arms has post that extend therefrom.

8. The lawnmower of claim 7, wherein one end of the brake actuating rod is mounted to the park brake handle and a second end of the brake actuating rod is affixed to a bell-crank linkage comprising two offset links with an extension arm that extends transverse across the mower chassis connecting the two links.

9. The lawnmower of claim 8, wherein the interlock arms are linked to the park brake handle so that movement of the park brake handle causes movement of the interlock arm.

10. The lawnmower of claim 9, wherein an edge of the control plate has a notch formed therein, the notch being located in the control plate so that when the control arm and the control plate are in the neutral position, the notch aligns with the post on the interlock arm.

11. The lawnmower of claim 10, wherein when the parking brake handle is rotated to the engaged position, thereby causing the interlock arms to move in a rearward direction, the post is received in the aligned notch and when the parking brake handle is rotated toward the engaged position while the control lever and control plate were not in the neutral position, the notch does not align with the post on the interlock arm an the post would contact the edge of the control plate, thereby preventing the parking brake handle from being positioned in the engaged position.

12. The lawnmower of claim 11, wherein the control plates have substantially identical notches such that the parking brake system can only be engaged when both of the control levers are in the neutral position.

13. A riding lawnmower comprising:

a chassis;

a power source;

first and second drive wheels at least partially supporting said chassis and rotatable via the power source to cause movement of said lawnmower;

first and second control levers associated with and controlling first and second drive systems, respectively, to control the direction and speed of rotation of said first and second drive wheels, respectively, each of said control levers having a neutral position in which the associated drive system does not cause rotation of the associated drive wheel;

a park brake system operatively interconnected with at least one of said drive wheels; and

an interlock means interfacing said parking system with said control levers, said interlock means preventing the parking brake system from engaging when said first and/or second control levers are not said neutral position, and interlock means permitting said parking brake system to engage when said first and second control levers are in said neutral position.

14. The lawnmower of claim 13 wherein said interlock means comprises a parking brake handle movable between an engaged position and a disengaged position to cause said park brake system to respectively resist and not resist rotation of said at least one drive wheel, and said interlock means further comprises first and second interlock arms linked to said park brake handle, said interlock arms having respective portions configured to be received by said control levers when said control levers are in a neutral position.

15. The lawnmower of claim 14 wherein each of said control levers comprises a plate member having a notch therein, said notch being located such that when said control lever is in said neutral position, a portion of a respective interlock arm is received within said notch when the park brake handle is placed in said engaged position, and when said control lever is not in said neutral position, said respective interlock arm contacts the plate member and prevents the park brake handle from being placed in said engaged position.

16. The lawnmower of claim 15, further comprising a parking brake sensor configured to determine when said parking brake handle is in the engaged position, said sensor interfacing with a starting device for starting said power source, wherein said sensor prevents said starting device from starting said power source when said parking brake handle is not in said engaged position, and

17. A riding lawnmower comprising:

a chassis;

an engine mounted to said chassis;

a rotary cutting blade selectively rotated by said engine;

first and second drive wheels at least partially supporting said chassis and rotatable to cause movement of said chassis;

first and second control levers associated with and controlling first and second drive systems, respectively, to control the direction and speed of rotation of said first and second drive wheels, respectively, each of said control levers having a neutral position in which the associated drive system does not cause rotation of the associated drive wheel;

a parking brake system operatively interconnected with said one of said wheels;

a parking brake handle interconnected with said chassis and movable between an engaged position and a disengaged position to cause said parking brake system to respectively resist and not resist rotation of said one wheel;

a brake sensor determining when said parking brake handle is in the engaged position, said brake sensor preventing an associated starting device from starting said engine when said parking brake handle is not in said engaged position, said starting device not using sensors separate from said brake sensor to determine whether said control levers are in said neutral positions.

18. The lawnmower of claim 17, wherein said brake sensor includes a plunger depressed by a finger in response to movement of said parking brake handle toward said engaged position.

19. The lawnmower of claim 18 further comprising an interlock mechanism interfacing with said parking system, said park brake interlock mechanism comprising a parking brake handle movable between an engaged position and a disengaged position to cause said park brake system to respectively resist and not resist rotation of said at least one drive wheel, said interlock mechanism interfacing said park brake handle and with said control levers such that when said first and second control levers are in said neutral position, said interlock mechanism permits said parking brake handle to be placed in said engaged position, and when said first and/or second control levers are not in said neutral position, said interlock mechanism prevents said parking brake handle from being placed in said engaged position.

20. The lawnmower of claim 19 wherein each of said control levers comprises a plate member having a notch therein, said notch being located such that when said control lever is in said neutral position, a portion of said interlock mechanism is received within said notch when the park brake handle is placed in said engaged position, and when said control lever is not in said neutral position, said interlock mechanism contacts the plate member and prevents the park brake handle from being placed in said engaged position and wherein said park brake interlock mechanism comprises first and second interlock arms linked to said park brake handle, said interlock arms having respective portions configured to be received within said notches in said control plates.