Hydraulic drivetrain, method of starting same, power generator and method of starting same

Patent metadata

Field	Value
Publication number	US-10626844-B2
Application number	US-201816111916-A
Country	US
Kind code	B2
Filing date	Aug 24, 2018
Priority date	Aug 25, 2017
Publication date	Apr 21, 2020
Grant date	Apr 21, 2020

Abstract

The present invention provides a hydraulic drive train including a check valve provided in a return oil passage disposed between a branching position of a first branching oil passage and a branching position of a second branching oil passage, wherein at the time of starting of startup of the hydraulic drive train, the switching valve is closed, the opening degree of the flow rate adjusting valve is set to the initial opening degree, the on-off valve is opened, the boost pump is driven by the drive motor, and the hydraulic oil is supplied to the hydraulic pump, thereby assisting the rotational speed of the vanes by the hydraulic oil.

First claim

What is claimed is:

1. A hydraulic drive train comprising:
a hydraulic pump configured to be rotated by rotation of a first rotating shaft provided with vanes, wherein the first rotating shaft is rotated by the action of the vanes;
a hydraulic motor configured to rotate a second rotating shaft connected to a power generator;
a supply oil passage configured to supply hydraulic oil from the hydraulic pump to the hydraulic motor;
a return oil passage configured to return the hydraulic oil from the hydraulic motor to the hydraulic pump;
a bypass oil passage configured to connect the return oil passage to the supply oil passage;
a switching valve provided in a portion of the supply oil passage located to be closer to the hydraulic motor side than a connection position between the supply oil passage and the bypass oil passage;
a flow rate adjusting valve provided in the bypass oil passage;
an oil tank configured to store the hydraulic oil therein;
a first branching oil passage which is branched from a portion of the return oil passage located to be closer to the hydraulic pump side than a connection position between the return oil passage and the bypass oil passage, and has a distal end reaching the hydraulic oil stored in the oil tank;
a boost pump which is provided in the first branching oil passage and is configured to supply hydraulic oil from the oil tank at a predetermined pressure;
a drive motor configured to drive the boost pump;
a second branching oil passage which is branched from a portion of the return oil passage located to be closer to the hydraulic motor side than a branching position of the first branching oil passage, and has a distal end reaching the hydraulic oil stored in the oil tank;
an on-off valve provided in the second branching oil passage and configured to be capable of closing the second branching oil passage; and
a check valve provided in the return oil passage located between the branching position of the first branching oil passage and the branching position of the second branching oil passage.

2. The hydraulic drive train according to claim 1 , further comprising:
a third branching oil passage which is branched from a position of the return oil passage between the branching position of the first branching oil passage and the hydraulic pump, and which has a distal end reaching the hydraulic oil stored in the oil tank; and
a relief valve which is provided in the third branching oil passage and is configured to open when reaching a predetermined pressure,
wherein the relief valve is configured to be able to switch the predetermined pressure between low-pressure setting and high-pressure setting depending on an operating state.

3. The hydraulic drive train according to claim 2 , further comprising:
a control device electrically connected to the switching valve, the flow rate adjusting valve, and the on-off valve,
wherein the control device is configured to perform a control of closing the switching valve and opening the on-off valve at the time of starting of startup, and is configured to perform a control of setting the relief valve to the high pressure, and
the control device is configured to perform a control of opening the switching valve and closing the on-off valve at the time of normal operation after startup, and is configured to perform a control of switching the relief valve to low-pressure setting.

4. A power generator comprising:
the hydraulic drive train according to claim 1 ;
the vanes configured to be rotated by a fluid;
a mechanical brake configured to restrict a rotation of the vanes;
the first rotating shaft configured to be rotate together with the vanes;
the power generator connected to one end of the second rotating shaft; and
the second rotating shaft having the other end connected to the hydraulic motor,
wherein the hydraulic drive train is disposed between the first rotating shaft and the second rotating shaft.

5. The power generator according to claim 4 , wherein the vanes are rotated by an ocean current.

6. A method of starting a hydraulic drive train, wherein the hydraulic drive train includes a hydraulic pump configured to be rotated by rotation of a first rotating shaft provided with vanes, wherein the first rotating shaft is rotated by the action of the vanes; a hydraulic motor configured to rotate a second rotating shaft connected to a power generator; a supply oil passage configured to supply hydraulic oil from the hydraulic pump to the hydraulic motor; a return oil passage configured to return the hydraulic oil from the hydraulic motor to the hydraulic pump; a bypass oil passage configured to connect the return oil passage to the supply oil passage; a switching valve provided in a portion of the supply oil passage located to be closer to the hydraulic motor side than a connection position with the bypass oil passage; a flow rate adjusting valve provided in the bypass oil passage; an oil tank configured to store the hydraulic oil therein; a first branching oil passage which is branched from a portion of the return oil passage located to be closer to the hydraulic pump side than a connection position with the bypass oil passage, and has a distal end reaching the hydraulic oil stored in the oil tank; a boost pump which is provided in the first branching oil passage and is configured to supply the hydraulic oil from the oil tank at a predetermined pressure; a drive motor configured to drive the boost pump; a second branching oil passage which is branched from a portion of the return oil passage located to be closer to the hydraulic motor side than a connection position with the boost pump, and has a distal end reaching the hydraulic oil stored in the oil tank; an on-off valve provided in the second branching oil passage and configured to be capable of closing the second branching oil passage; and a check valve provided in the return oil passage located between the branching position of the first branching oil passage and the branching position of the second branching oil passage, the method comprising:
a first step of closing the switching valve, setting an opening degree of the flow rate adjusting valve to an initial opening degree and opening the on-off valve at the time of starting of startup of the hydraulic drive train;
a second step of driving the boost pump by the drive motor and supplying hydraulic oil to the hydraulic pump to assist the rotational speed of the vanes with the hydraulic oil;
a third step of controlling the rotational speed of the vanes by adjusting the opening degree of the flow rate adjusting valve;
a fourth step of setting the rotational speed of the vanes to a rotational speed at the time of the normal operation, when the rotational speed of the vanes except the assistance of the rotational speed of the vanes reaches a rotational speed exceeding a required torque; and
a fifth step of closing the on-off valve and opening the switching valve to start the normal operation.

7. The method of starting the hydraulic drive train according to claim 6 , wherein the hydraulic drive train includes a third branching oil passage which is branched from a position of the return oil passage between a branching position of the second branching oil passage and the hydraulic pump, and has a distal end reaching the hydraulic oil stored in the oil tank, and
a relief valve which is provided in the third branching oil passage and configured to open the third branching oil passage when reaching a predetermined pressure, and wherein
a control of setting the relief valve to high pressure is performed in the first step, and
a control of switching the relief valve to low-pressure setting is performed in the fifth step.

8. A method of starting a power generating device i

Assignees

• Mitsubishi Heavy Ind Ltd

Inventors

• Asano Shin
• Futahashi Kensuke
• Noda Yoshitomo
• Tokuyama Kyota
• Onodera Sho
• Okuda Yukihito

Classifications

• F03B13/10 Primary

  Submerged units incorporating electric generators or motors · CPC title

• F03B17/061 Primary

  with rotation axis substantially in flow direction · CPC title

• F03B15/005

  Starting, also of pump-turbines · CPC title

• F03B13/22

  using the flow of water resulting from wave movements to drive a motor or turbine {(F03B13/144 takes precedence)} · CPC title

• F05B2260/406

  through hydraulic systems · CPC title