Electrohydraulic device, method, and marine vessel or platform

Abstract

An electrohydraulic device includes an extender which is arranged to be actuated by hydraulic fluid, and a rotor of an electric motor, the rotor being arranged to rotate about a part of the extender. The rotor may have an annular body which encircles or surrounds part of the extender. There is also described a related method of use and a marine vessel or platform where the device may be applied.

Claims

1. An electrohydraulic device comprising: an extender comprising a first section and a second section, wherein the first section is arranged to be axially translated relative to the second section by hydraulic fluid; an electric motor arranged on an outside of the extender, the electric motor including a rotor comprising an annular body which encircles the extender and is arranged to rotate about said extender; and a pump comprising a drive shaft, wherein the rotor is arranged to drive the pump for pumping and supplying the hydraulic fluid for operating the extender; wherein the rotor is coupled to the drive shaft through a gear arrangement comprising gears which have a gear ratio therebetween.

2. A device as claimed in claim 1, wherein the extender comprises a hydraulic cylinder and a rod, and the rotor is arranged to rotate about a part of either the hydraulic cylinder or the rod.

3. A device as claimed in claim 2, wherein the rod is movable with respect to the hydraulic cylinder to extend or retract to vary or obtain a desired amount of extension or elongation of the extender.

4. A device as claimed in claim 1, further comprising a stator of the electric motor, disposed on the extender, the stator and rotator being arranged to cooperate upon operation of the motor to generate torque to rotate the rotor.

5. A device as claimed in claim 4, wherein the stator is arranged around an outside of the rotor.

6. A device as claimed in claim 4, wherein the stator and the rotor are mounted inside a casing attached to the extender, the stator being mounted so as to be attached fixedly with respect to the extender.

7. A device as claimed in claim 1, further comprising a tank provided on or incorporated in a part of the extender, the tank being configured for storing hydraulic fluid.

8. A device as claimed in claim 7, wherein the tank has an annular or part-annular storage space for hydraulic fluid, where the storage space is disposed around a part of the extender.

9. A device as claimed in claim 1, operable for manoeuvring or supporting a structure that subjects the device to a load, wherein the structure is any of a boom, or an arm of a crane, or a leg of an A-frame.

10. A device as claimed in claim 9, wherein the extender is operable to extend to a desired extension so as to tilt the structure.

11. A marine vessel or platform comprising: a structure supported on a deck of the vessel or platform; and an electrohydraulic device as claimed in claim 1, connected to the structure, and operable to actuate the extender to manoeuvre or support the structure in position relative to the vessel or platform.

12. A method of using the electrohydraulic device as claimed in claim 1, the method comprising at least the step of operating the extender, using the electric motor so as to rotate the rotor about a part of the extender.

Description

BRIEF DESCRIPTION OF DRAWINGS

(1) There will now be described, by way of example only, embodiments of the disclosure with reference to the accompanying drawings, in which:

(2) FIG. 1 is an example of a prior art vessel using an A-frame manoeuvrable by extenders;

(3) FIG. 2 is a schematic side representation an electrohydraulic device according to an embodiment of the disclosure applied in use to an A-frame in a first, upright configuration;

(4) FIG. 3 is a schematic side representation of FIG. 2 applied to the A-frame in a second, tilted configuration;

(5) FIG. 4 is a cross-sectional representation in close up of an electric motor of the electrohydraulic device of FIGS. 2 and 3, according to an embodiment of the disclosure;

(6) FIG. 5 is a pull-apart perspective representation of the parts of the electric motor of FIG. 4 in smaller scale;

(7) FIG. 6 is a perspective view of the motor of FIG. 4 when assembled in smaller scale still;

(8) FIG. 7 is an end on view of the motor of FIG. 4 when assembled in larger scale;

(9) FIG. 8 is a perspective view of part of the electrohydraulic device of FIG. 2 in close up; and

(10) FIG. 9 is a diagrammatic representation of a hydraulic circuit for controlling and supplying hydraulic fluid to actuate an extender of the electrohydraulic device of FIG. 2.

DETAILED DESCRIPTION OF THE DISCLOSED EXEMPLARY EMBODIMENTS

(11) Turning first to FIGS. 2 and 3, according to an embodiment of the disclosure, an electrohydraulic device 100 is depicted which includes a hydraulic actuator in the form of an extender 103, in this example used for positioning and manipulating an A-frame 101 on a deck 102 of a vessel. The extender 103 is actuated by hydraulic fluid and operates in the example to tilt the A-frame 101 by way of axial extension of the extender 103 between the deck 102 and the A-frame 101. The extender 103 has first end 106a which is connected to the deck and a second end 106b which is connected to the leg of the A-frame 101. The first end 106a is an end of a first section 103a of the extender, and the second end 106b is an end of a second section 103b of the extender.

(12) The first and second sections 103a, 103b are telescopically and movably coupled to one another, so that by telescoping action, the first section 103a can be axially translated relative to the second section 103b, so as to vary the end-to-end length of the extender 103.

(13) In the configuration of FIG. 3, the extender 103 is extended to have a greater length than in the configuration of FIG. 2. The first section 103a of the extender is stroked out telescopically from the second part 103b of the extender by a greater amount. The A-frame 104 is tilted to a greater extent accordingly. The ends 106a, 106b of the extender 103 are pivot connected to the deck and A-frame respectively so that the extender 103 extends linearly while also adapting its orientation as the A-frame is tilted. As can be seen, the A-frame 104 is connected to the deck 102 at a pivot 104 and is arranged to tilt about a horizontal pivot axis 105.

(14) An electric motor 130 is arranged on the extender 103, as will be described in further detail in the following, in addition to a pump 160, and a tank 170. The electric motor 130 has a rotor 141 arranged to rotate about a circumference of the first part 103a of the extender.

(15) In FIG. 4, the electric motor 130 is shown in close-up. The motor 130 includes a rotor 141 which has an annular body, e.g. in the form of a ring or sleeve, around the first part 103a of the actuator 103. The rotor 141 thus comprises a ring surrounding the shaft and is operable to be rotated about the shaft, when the motor is activated.

(16) The motor 103 has a casing 131 having first and second parts 131a, 131b connected together and fastened by fasteners 132. In this example, the casing 131 is mounted onto an outside of the section 103a of the extender, although in general it may be similarly mounted in different locations along the extender. The part 103a is in the form of a shaft.

(17) The rotor 141 is housed on an inside of the casing 131. The rotor 141 is supported on the shaft on bearings 143a, 143b. The bearings 143a, 143b are arranged on collars 144a, 144b of the casing 131, and are held in place by circlips 145a, 145b. The rotor 141 bears against the bearings 143a, 143b as it rotates. The bearings can facilitate positioning the rotor 141 within the casing 131 and may reduce friction effects.

(18) The motor 130 further includes a stator 142 which in this example also has an annular body constituting a ring or sleeve which surrounds the rotor 141. The stator 142 is fixed to the casing 131 by fasteners 133. The stator 142 comprises electrical windings (not shown) configured to be connected to an electrical power supply to operate the motor to turn the rotor 141 about the shaft. The motor may thus have an electrical connector (not shown) for transmitting electrical power to the motor.

(19) The motor 130 is configured to be arranged to drive the pump 160. To this end, the motor 130 has a planetary gear 146 in engagement with gear ring around an outer rim of the body of the rotor 141. The gear 146 has a central axial extension 147 for connection with a drive shaft of the pump. The gear 146 is driven to rotate by rotation of the rotor 141, at a rate dependent upon the diameter ratio of the rotor 141 and the gear 146, and the speed of the rotor. By way of the engagement with the rotor, torque generated by rotation of the rotor 141 can be transmitted directly and efficiently to the drive shaft of the pump.

(20) In FIG. 5, the individual components for the assembly of the motor 130 are illustrated. In FIG. 6, an assembled unit of the motor 130 is depicted, and FIG. 7 highlights the arrangement of the planetary gear 146 of the motor 130. Referring to FIGS. 5 to 7, the rotor 141 rotates relative to the casing 131 and/or the stator 142 as indicated by the arrows R in FIG. 7. The rotation of the rotor 141 causes the gear 146 to turn as indicated by arrows G.

(21) By being arranged ring-wise around the shaft, the motor 130 can be provided in a highly compact manner on the extender. When applied to an A-frame, the provided motor may advantageously be provided at a location along the extender close to the deck, which can facilitate access and service and maintenance.

(22) Turning now to FIG. 8, the shaft is shown with the motor 130 mounted to it and with the pump 160 connected so as to be driven by the motor 130 via the extension 147 of the gear 146. In addition, as seen in FIG. 8, the shaft is additionally provided with the tank 170 thereupon. The tank 170 has a wall extending around the shaft so as to define a storage region, for instance annular, for storing fluid in the tank in an annulus around the shaft of the section 103a of the extender. The pump 160 is driven by the motor 130 to pump fluid from the tank 170 to a hydraulic chamber of the extender for operating the extender. As can be seen, the pump 160 is positioned on an outside of the extender, and in a discrete location along the circumference around the extender.

(23) The fluid in the hydraulic chamber is supplied in use to provide a pressure in the chamber for controlling the relative position of the first and second sections 103a, 103b of the extender. The hydraulic fluid may be applied in the chamber so as to transmit a force to the first and/or second sections 103a, 103b of the extender to drive the first and second parts of the extender 103 to extend or retract or to operate the extender so that the first and second parts maintain their configuration under an external load applied to the extender. The hydraulic chamber may be contained inside either of the first or second sections 103a, 103b of the extender.

(24) The extender 103 is provided also with a hydraulic circuit 180 for operating it. A typical supply circuit 180 is exemplified diagrammatically in FIG. 9, where hydraulic fluid is supplied to first or second chambers 108a, 108b of the linear extender 103, and is extracted from the other one of the chambers 108a, 108b. Pipes for communicating hydraulic fluid are indicated by solid lines, and control lines for operating valves are indicated with dashed lines.

(25) In embodiments described above, the extender can advantageously be provided with the circuitry and components necessary for powering the actuator in a compact and accessible assembly. This may provide significant space saving, reduce risks to personnel, and reduce downtime in the application of hydraulic cylinders applied to tilting, raising or lowering, or positioning A-frames, booms, or arms or the like or other large structures on marine vessels.

(26) Various modifications and improvements may be made without departing from the scope of the invention that is claimed below.