Hydraulically assisted gear shift mechanism for a marine propulsion device

• US 6,755,703 B1
• Filed: 01/03/2003
• Issued: 06/29/2004
• Est. Priority Date: 01/03/2003
• Status: Expired due to Fees

• Current Assignee: Brunswick Corporation
• Original Assignee: Brunswick Corporation
• Inventors: Erickson, James E.
• Primary Examiner(s): Sotelo, Jesus D.
• Application Number:
  US10/336,453
• Time in Patent Office: 543 Days
• Field of Search: 440/61.R, 440/6.H, 440/75, 440/84
• US Class Current: 440/75
• CPC Class Codes: B63H 21/213 Levers or the like for controlling the engine or the transmission, e.g. single hand control levers
• CPC Class Codes: B63H 21/22 the propulsion power units being controlled from exterior of engine room, e.g. from navigation bridge; Arrangements of order telegraphs
• CPC Class Codes: F16H 2059/0256 Levers for forward-reverse selection only, e.g. for working machines having a separate lever for switching between forward and reverse mode
• CPC Class Codes: F16H 59/02 Selector apparatus
• CPC Class Codes: F16H 61/30 Hydraulic or pneumatic motors or related fluid control means therefor

Abstract

A hydraulic assist mechanism for use in conjunction with a gear shift device provides a hydraulic cylinder and piston combination connected by a linkage to a gear shift mechanism. Hydraulic pressure can be provided by a pump used in association with either a power trim system or a power steering system. Hydraulic valves are used to pressurize selected regions of the hydraulic cylinder in order to actuate a piston which is connected, by an actuator, to the gear shift mechanism.

Claims

1. A gear shift assist mechanism for a marine propulsion device, comprising:

a gear shift mechanism being alternately movable into forward, neutral, and reverse positions;

a manually operable gear position selector;

a hydraulic pump;

a hydraulic cylinder connected in fluid communication with said hydraulic pump;

a hydraulic piston disposed within said hydraulic cylinder;

an actuator connected to said piston, said actuator being connected to said gear shift mechanism, whereby movement of said piston relative to said cylinder causes said gear shift mechanism to move between selected ones of said forward, neutral, and reverse positions; and

a switching device connected in fluid communication with said cylinder for conducting hydraulic pressure from said hydraulic pump into a selected region of said hydraulic cylinder in response to a signal received from said manually operable gear position selector.

2. The mechanism of claim 1, wherein:

said piston is movable to a first end of said cylinder to cause said gear shift mechanism to move into said forward position when said selected region is a first region of said hydraulic cylinder.

3. The mechanism of claim 2, wherein:

said piston is movable to a second end of said cylinder to cause said gear shift mechanism to move into said reverse position when said selected region is a second region of said hydraulic cylinder.

4. The mechanism of claim 3, wherein:

said piston is movable to a central position of said cylinder to cause said gear shift mechanism to move into said neutral position when said hydraulic pressure is blocked from fluid communication with both of said first and second regions.

5. The mechanism of claim 1, further comprising:

a position biasing component disposed within said cylinder to urge said piston toward a position within said cylinder which corresponds to said neutral position of said gear shift mechanism.

6. The mechanism of claim 5, wherein:

said position biasing component comprises a pair of springs disposed within said hydraulic cylinder.

7. The mechanism of claim 1, further comprising:

a pressure accumulator connected in fluid communication between said hydraulic pump and said switching device.

8. The mechanism of claim 1, wherein:

said gear shift mechanism comprises a shift shaft.

9. The mechanism of claim 1, wherein:

said hydraulic pump is connected in fluid communication with a power steering mechanism of said marine propulsion system.

10. The mechanism of claim 1, wherein:

said hydraulic pump is connected in fluid communication with a power trim system of said marine propulsion system.

11. The mechanism of claim 1, wherein:

said switching device is connected in signal communication with said manually operable gear position selector.

12. The mechanism of claim 10, further comprising:

an electrical switch associated with said manually operable gear position selector and responsive to the position of said manually operable gear position selector, said electrical switch providing said signal communication between said switching device and said manually operable gear position selector.

13. A gear shift assist mechanism for a marine propulsion device, comprising:

a gear shift mechanism being alternately movable into forward, neutral, and reverse positions;

a manually operable gear position selector;

a hydraulic pump;

a hydraulic cylinder connected in fluid communication with said hydraulic pump;

a hydraulic piston disposed within said hydraulic cylinder;

an actuator connected to said piston, said actuator being connected to said gear shift mechanism, whereby movement of said piston relative to said cylinder causes said gear shift mechanism to move between selected ones of said forward, neutral, and reverse positions;

a switching device connected in fluid communication with said cylinder for conducting hydraulic pressure from said hydraulic pump into a selected region of said hydraulic cylinder in response to a signal received from said manually operable gear position selector, said piston being movable to a first end of said cylinder to cause said gear shift mechanism to move into said forward position when said selected region is a first region of said hydraulic cylinder, said piston being movable to a second end of said cylinder to cause said gear shift mechanism to move into said reverse position when said selected region is a second region of said hydraulic cylinder, and said piston being movable to a central position of said cylinder to cause said gear shift mechanism to move into said neutral position when said hydraulic pressure is blocked from fluid communication with both of said first and second regions; and

a position biasing component disposed within said cylinder to urge said piston toward a position within said cylinder which corresponds to said neutral position of said gear shift mechanism.

14. The mechanism of claim 13, wherein:

said position biasing component comprises a pair of springs disposed within said hydraulic cylinder.

15. The mechanism of claim 14, further comprising:

a pressure accumulator connected in fluid communication between said hydraulic pump and said switching device.

16. The mechanism of claim 15, wherein:

said switching device is connected in signal communication with said manually operable gear position selector.

17. The mechanism of claim 16, further comprising:

an electrical switch associated with said manually operable gear position selector and responsive to the position of said manually operable gear position selector, said electrical switch providing said signal communication between said switching device and said manually operable gear position selector.

18. A gear shift assist mechanism for a marine propulsion device, comprising:

a gear shift mechanism being alternately movable into forward, neutral, and reverse positions;

a manually operable gear position selector;

a hydraulic pump;

a hydraulic cylinder connected in fluid communication with said hydraulic pump;

a hydraulic piston disposed within said hydraulic cylinder;

an actuator connected to said piston, said actuator being connected to said gear shift mechanism, whereby movement of said piston relative to said cylinder causes said gear shift mechanism to move between selected ones of said forward, neutral, and reverse positions;

a switching device connected in fluid communication with said cylinder for conducting hydraulic pressure from said hydraulic pump into a selected region of said hydraulic cylinder in response to a signal received from said manually operable gear position selector, said piston being movable to a first end of said cylinder to cause said gear shift mechanism to move into said forward position when said selected region is a first region of said hydraulic cylinder, said piston being movable to a second end of said cylinder to cause said gear shift mechanism to move into said reverse position when said selected region is a second region of said hydraulic cylinder, and said piston being movable to a central position of said cylinder to cause said gear shift mechanism to move into said neutral position when said hydraulic pressure is blocked from fluid communication with both of said first and second regions, said switching device being connected in signal communication with said manually operable gear position selector; and

a position biasing component disposed within said cylinder to urge said piston toward a position within said cylinder which corresponds to said neutral position of said gear shift mechanism.

19. The mechanism of claim 18, wherein:

said position biasing component comprises a pair of springs disposed within said hydraulic cylinder.

20. The mechanism of claim 19, further comprising:

a pressure accumulator connected in fluid communication between said hydraulic pump and said switching device; and

an electrical switch associated with said manually operable gear position selector and responsive to the position of said manually operable gear position selector, said electrical switch providing said signal communication between said switching device and said manually operable gear position selector.