Saildrive arrangement

Abstract

A saildrive arrangement (1) which comprises an upper unit (13) to be positioned inside a hull (5) of a sailboat (7) and a lower unit (14) which is arranged to protrude from the bottom (6) of the hull (5). The upper unit (13) comprises an input shaft (4) to be connected to an engine (2) and the lower unit (14) comprises a propeller shaft (9). A brake (15), for locking the rotational movement of the propeller shaft (9), is located in the upper unit (13). The saildrive arrangement (1) is incorporated into a sailboat (7) with a hull (5) and an engine (2).

Claims

1. A saildrive arrangement comprising: an upper unit for positioning inside a hull of a sailboat, and a lower unit for being arranged to protrude from a bottom of the hull, the upper unit comprising an input shaft for connection to an engine, and the lower unit comprising a propeller shaft, wherein a brake, to lock the rotational movement of the propeller shaft, is located in the upper unit.

2. The saildrive arrangement according to claim 1, wherein the upper unit comprises an upper bevel gear mechanism which connects the input shaft to an intermediate shaft, and the lower unit comprises a lower bevel gear mechanism which connects the intermediate shaft to the propeller shaft.

3. The saildrive arrangement according to claim 2, wherein a rotatable element of the brake is rotationally fixed to a hub of a first bevel gear of the upper bevel gear mechanism and a stationary element of the brake is rotationally fixed to a housing of the saildrive arrangement.

4. The saildrive arrangement according to claim 3, wherein the rotatable and the stationary elements of the brake comprise at least one friction disk.

5. The saildrive arrangement according to claim 1, wherein the brake is engageable by a locking spring and disengageable by hydraulic pressure supplied by a hydraulic pump which is driven by the input shaft.

6. The saildrive arrangement according to claim 2, wherein the upper bevel gear mechanism comprises a first bevel gear and a second bevel gear which are both arranged rotatable around a rotation axis of the input shaft and the first and the second bevel gears are constantly meshing with a third bevel gear which is rotationally fixed to the intermediate shaft, wherein the first and the second bevel gears are selectively fixable to the input shaft by a first clutch and a second clutch respectively in order to engage a forward propulsion direction or a reverse propulsion direction.

7. The saildrive arrangement according to claim 6, wherein the first clutch and the second clutch are both hydraulic multi-disk clutches which are engageable by a pressure supplied by a hydraulic pump which is driven by the input shaft.

8. The saildrive arrangement according to claim 7, wherein hydraulic pressure channels are provided inside the input shaft to connect the hydraulic pump to the first clutch and the second clutch.

9. The saildrive arrangement according to claim 7, wherein the hydraulic pump is positioned inside a cover of a housing of an upper unit of the saildrive arrangement.

10. The saildrive arrangement according to claim 1, wherein the saildrive arrangement comprises a disabling element for mechanically disabling the brake.

11. The saildrive arrangement according to claim 10, wherein the disabling element is a screw bolt which can be screwed into a housing of the saildrive arrangement until a front part of the disabling element positively locks a pressure piston of the brake in a disengaged position.

12. A sailboat with a hull and a saildrive, the saildrive comprising an engine which is positioned inside the hull and a saildrive arrangement comprising: an upper unit for positioning inside the hull of the sailboat, and a lower unit for being arranged to protrude from a bottom of the hull, the upper unit comprising an input shaft for connection to an engine, and the lower unit comprising a propeller shaft, wherein a brake, to lock the rotational movement of the propeller shaft, is located in the upper unit.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The following detailed description of a preferred embodiment of the invention in connection with the accompanying drawings will help to understand the objects, features and advantages of the invention, wherein:

(2) FIG. 1 shows a schematic layout of a saildrive and an arrangement according to the invention;

(3) FIG. 2 shows a partial section of the upper unit of a saildrive arrangement according to the invention;

(4) FIG. 3 shows another partial section with the disabling element in an idle position and

(5) FIG. 4 shows the partial section of FIG. 3 with the disabling element in a disabling position.

DETAILED DESCRIPTION OF THE INVENTION

(6) A saildrive arrangement 1 can be seen in FIG. 1. It is driven by an engine 2, for example an internal combustion engine, which is located inside the hull 5 of a sailboat 7. The output shaft 3 of the engine 2 is coupled to an input shaft 4 of the saildrive arrangement 1. Input shaft 4 enters into a housing 21 of an upper unit 13. The upper unit 13 is also located inside the hull 5. The engine 2 and the upper unit 13 are fastened to the hull 5 or to structural parts inside of the hull 5.

(7) The upper unit 13 includes an upper bevel gear mechanism 11 and a brake 15 in the form of a multi-disk brake. The upper bevel gear mechanism 11 and the brake 15 are located inside the housing 21 of the upper unit 13. The upper bevel gear mechanism 11 connects the input shaft 4 to a vertically arranged intermediate shaft 8 and a lower bevel gear mechanism 12 connects the intermediate shaft 8 to a horizontally arranged propeller shaft 9. A propeller 10 is rigidly fixed to the propeller shaft 9. The lower bevel gear mechanism 12 and the propeller shaft 8 are arranged in a lower unit 14 which protrudes from the bottom 6 of the hull 5.

(8) The brake 15 comprises stationary elements 16 and rotatable elements 17 in the form of friction disks. The rotatable friction disks 17 of the brake 15 are rotationally fixed to a hub 24 of a first bevel gear 18 of the upper bevel gear mechanism 11. The rotatable friction disks 17 and the first bevel gear 18 are arranged to rotate together around rotation axis 22 which is also the rotation axis of the input shaft 4. Hence, the rotatable frictions discs 17 of the brake 15 with the first bevel gear 18 are coaxially aligned with the input shaft 4. The stationary disks 16 are rotationally fixed to the housing 21.

(9) FIG. 2 shows the upper unit 13 of the saildrive arrangement 1 more detailed. The brake 15 is engageable by a locking spring 27 and disengageable by hydraulic pressure provided by a hydraulic pump 29 which is driven by the input shaft 4. When the engine 2 is running the input shaft 4 is driven by the output shaft 3 and the hydraulic pump 29 on the input shaft 4 provides hydraulic pressure to a pressure chamber 26. The hydraulic pressure in pressure chamber 26 acts on a pressure piston 28 and moves it in axial direction away from the friction disks 16, 17 of the brake 15 as soon a certain pressure level is reached. In FIG. 2 the assembly it shown when the engine 2 is running and the brake 15 is disengaged by the hydraulic pressure.

(10) As soon as the hydraulic pressure decreases below said pressure level, the locking spring 27 will press the pressure piston 28 in axial direction towards the friction disks 16, 17 of the brake 15, thereby locking the brake 15. Hence, the propeller shaft 9 is locked. This will happen as soon as or shortly after the engine 2 is stopped. The locking spring 27 is formed by several cup springs which press the pressure piston 28 against the friction disks 16, 17. The cup springs are biased against the housing 21 to enable the cup springs to generate the friction force for the spring-actuated brake 15. This way it is ensured, that a rotation of the propeller is prevented when the engine is not running.

(11) The upper bevel gear mechanism 11 comprises a first bevel gear 18, a second bevel gear 19 and a third bevel gear 20. The first bevel gear 18 and the second bevel gear 19 are both arranged rotationally around a rotation axis 22 of the input shaft 4. The first and second bevel gears 18 and 19 are constantly meshing with the third bevel gear 20 which is rotationally fixed to the intermediate shaft 8. The third bevel gear 20 is fixed to the intermediate shaft 8 and rotates together with the intermediate shaft 8 around a vertical axis 23 during operation of the saildrive.

(12) The first bevel gear 18 and the second bevel gear 19 are selectively fixable to the input shaft 4 by closing the corresponding first clutch 26 or second clutch 27 in order to engage a forward or reverse propulsion direction. This means that either first bevel gear 18 or the second bevel gear 19 can be fixed to the input shaft 4. When both clutches 26 and 27 are open, none of the bevel gears 18, 19 is fixed to the input shaft 4. In this case the saildrive runs in an idle gear with no driving connection between the engine 2 and the propeller shaft 9 is realized.

(13) The first clutch 30 and the second clutch 32 are both hydraulic multi-disk clutches which are engageable by a pressure provided by hydraulic pump 29 which is driven by the input shaft 4. There is only one hydraulic pump 29 to provide hydraulic pressure to the brake 15 and to the first clutch 30 and the second clutch 32.

(14) Inner clutch disks of the first clutch 30 are rotationally fixed to a first inner clutch disk carrier 31. Said first inner clutch disk carrier 31 is fixed to the first bevel gear 18. The first inner clutch disk carrier 31 is supported on the input shaft 4 by a first needle bearing 42. Inner clutch disks of the second clutch 32 are rotationally fixed to a second inner clutch disk carrier 33. Said second inner clutch disk carrier 33 is fixed to the second bevel gear 19. The second inner clutch disk carrier 33 is supported on the input shaft 4 by a second needle bearing 43.

(15) Outer clutch disks of the first and second clutch 30 and 32 are rotationally fixed to outer clutch disk carrier 36. The outer clutch disk carrier 36 is fixed to the input shaft 4. Additionally the outer clutch disk carrier 36 carries a first and a second clutch piston 34 and 35 which limit the pressure chambers of the first and the second clutch 30, 32 and provide the necessary force for clutch engagement as soon as hydraulic pressure is provided to the corresponding pressure chamber.

(16) The hydraulic pump 29 in this embodiment is a positive displacement pump which is positioned right beside the feedthrough for the input shaft 4 in housing 21. Rotatable parts of the hydraulic pump 4 are fastened directly on the input shaft 4. Stationary parts of the hydraulic pump 4 are fastened inside a sealing cover 38 of housing 21 of the upper unit 13. All parts of the hydraulic pump 29 are positioned inside the sealing cover 38. The sealing cover 38 is equipped with a sealing ring 39 around the input shaft 4 at said feedthrough to protect the upper unit 13 from oil leakage and contamination from the outside.

(17) Pressure bores 40 and a hydraulic valve 41 are provided inside a wall of the housing 21 of the upper unit 13 to selectively connect the pressure chambers 26 of the brake 15 or the first or second clutch 30, 32 with hydraulic pressure. There are further hydraulic pressure channels 37 provided inside the input shaft 4 and inside the outer clutch disk carrier 36 to connect the hydraulic pump 29 with pressure chambers of the first clutch 30 and the second clutch 32. This means that all components of the hydraulic system for the brake 15 and the first and second clutch 30 and 32 are part of the upper unit 13 and located inside the housing 21 of the upper unit 13.

(18) FIG. 3 and FIG. 4 both show a section of a part of the upper unit 13 with the disabling element 44. By means of the disabling element 44 the brake 15 can be disabled mechanically, for example in sailboats with fixed propellers which shall rotate during sailing. FIG. 3 shows the disabling element in an idle position, so that the brake is enabled. FIG. 4 shows the disabling element 44 in the disabling position, so that the brake 15 cannot be used and the disengaged position of the brake 15 is secured by the disabling element 44.

(19) The disabling element 44 is formed as a threaded pin which can be screwed into the housing 21 of the saildrives upper unit 13. In the disabling position in FIG. 4 a front part 45 of the threaded pin 44 positively locks the pressure piston 28 of the brake 15 in a disengaged position of the brake 15. The brake 15 is mechanically disabled.

(20) Whereas in the idle or retracted position of the threaded pin 44 as shown in FIG. 3 the pressure piston 28 of the brake 15 is not blocked by the front part 45 of the threaded pin 44. The pressure piston 28 will be pressed against the stationary and rotatable elements 16, 17, that are the pressure plates of the brake 15 by the force of spring 27, as long as the force generated on the pressure piston 28 by the hydraulic pressure in pressure chamber 26 is lower than the force of spring 27. A spacer 47 is arranged between the head 46 of the threaded pin 44 and the housing 21 in order to fasten the threaded pin 44 in its predefined idle position. Hence, the brake can easily be enabled and disabled from outside of the housing 21, by screwing in or out the threaded pin 44 and placing the spacer 47 as indicated.

REFERENCE NUMERAL

(21) 1 saildrive arrangement 2 engine 3 output shaft 4 input shaft 5 hull 6 bottom 7 sailboat 8 intermediate shaft 9 propeller shaft 10 propeller 11 upper bevel gear mechanism 12 lower bevel gear mechanism 13 upper unit 14 lower unit 15 brake 16 stationary element 17 rotatable element 18 first bevel gear 19 second bevel gear 20 third bevel gear 21 housing 22 rotation axis 23 vertical axis 24 hub 25 brake disk carrier 26 pressure chamber 27 spring 28 pressure piston 29 hydraulic pump 30 first clutch 31 first inner clutch disk carrier 32 second clutch 33 second inner clutch disk carrier 34 first clutch piston 35 second clutch piston 36 outer clutch disk carrier 37 pressure channels 38 sealing cover 39 sealing ring 40 pressure bores 41 hydraulic valve 42 first needle bearing 43 second needle bearing 44 disabling element 45 front part 46 head 47 spacer