Accumulator module for hydromechanical spring-loaded drive

Patent metadata

Field	Value
Publication number	US-11286959-B2
Application number	US-201616063835-A
Country	US
Kind code	B2
Filing date	Dec 7, 2016
Priority date	Dec 23, 2015
Publication date	Mar 29, 2022
Grant date	Mar 29, 2022

Abstract

The invention relates to an accumulator module for a hydromechanical spring-loaded drive, wherein the spring-loaded drive is provided to actuate a high-voltage power switch (12), and wherein the accumulator module contains a pressure-tight housing (1), an accumulator piston (2) which protrudes into the housing (1) and is axially moveable in the housing (1), and a sealing cover (4) which seals the housing in an pressure-tight manner. In addition, at least one connecting channel (5, 6) is provided, which is introduced into the housing (1) for transporting a highly pressurised fluid present between the inner wall (7) of the housing and the head (3) of the accumulator piston to a high-pressure channel (11) of the spring-loaded drive, which channel is outside the housing. In order to increase the service life of the accumulator module, at least one pressure relief groove (8) is circumferentially applied to the head (3) of the accumulator piston.

First claim

The invention claimed is:

1. An accumulator module comprising:
a pressure-tight housing;
an accumulator piston that protrudes into the housing and is axially movable in the housing between a first end of the housing and a second end of the housing, the accumulator piston comprising:
a head having a first diameter;
the head comprising a terminal surface facing towards the second end of the housing and a circumference peripherally connected with the terminal surface;
a guide strip fastened to the circumference of the head, the guide strip having a second diameter greater than the first diameter, the guide strip configured to contact an inner wall of the housing during an operation of the accumulator module to maintain a gap between the circumference of the head and the inner wall, the inner wall having a third diameter greater than the first diameter; and
at least one pressure-relief groove in the head, the at least one pressure-relief groove disposed around the circumference of the head;

a closure cover that closes the first end of the housing in a pressure-tight manner; and
a pair of connection ducts in the housing, for conveying a highly pressurized fluid to a high-pressure duct located outside the housing, such that the highly pressurized fluid is located in the gap between the inner wall of the housing and the head of the accumulator piston during the operation of the accumulator module, and such that the guide strip is maintained between the second end of the housing and the pair of connection ducts when the accumulator piston is in contact with the first end of the housing,
the pair of connection ducts comprising a first connection duct maintained between the first end of the housing and the at least one pressure-relief groove during the entire operation of the accumulator module, and a second connection duct located between the second end of the housing and the at least one pressure-relief groove during a portion of the operation of the accumulator module,
the guide strip fastened to the circumference of the head in between the terminal surface of the head and the at least one pressure-relief groove, the accumulator piston further comprising a single through-bore comprising an axial bore portion and a radial bore portion, the axial bore portion axially traversing into the terminal surface of the head and extending on a longitudinal axis of the accumulator piston, the radial bore portion radially traversing through the circumference of the head and not traversing into the at least one pressure-relief groove, the axial bore portion substantially perpendicular to the radial bore portion and in fluid communication with the axial bore portion, the axial bore portion configured to allow the highly pressurized fluid to flow between a base of the housing and the radial bore portion, the radial bore portion configured to allow the highly pressurized fluid to flow between the axial bore portion and the pair of connection ducts, and the at least one pressure-relief groove positioned in between the guide strip and the radial bore portion, so as to maintain the pressure-relief effect provided by the at least one pressure-relief groove.

2. The accumulator module as claimed in claim 1 , wherein the at least one pressure-relief groove comprises at least two pressure-relief grooves of the same geometric design in the head of the accumulator piston, so as to run in a circumferential direction of said head and so as to have the same spacing from one another.

3. The accumulator module as claimed in claim 1 , wherein the guide strip is disposed so as to be parallel with the at least one pressure-relief groove.

4. The accumulator module as claimed in claim 1 , wherein the guide strip comprises polytetrafluoroethylene.

5. The accumulator module as claimed in claim 1 , wherein the guide strip in relation to the at least one pressure-relief groove is disposed on the head of the accumulator piston so as to be disposed within the housing between the at least one pressure-relief groove and the second end of the housing.

6. The accumulator module as claimed in claim 1 , wherein the closure cover is configured to axially guide the accumulator piston.

7. The accumulator module as claimed in claim 1 , wherein a first distance between one of the pair of connection ducts and the closure cover is less than a second distance between the at least one pressure-relief groove and the closure cover during the operation of the accumulator module.

8. The accumulator module as claimed in claim 1 , wherein the second connection duct is between the first end of the housing and the at least one pressure-relief groove during another portion of the operation of the accumulator module.

9. The accumulator module as claimed in claim 1 , wherein the first connection duct of the pair of connection ducts is narrower than the second connection duct of the pair of connection ducts.

10. The accumulator module as claimed in claim 9 , wherein the first connection duct is located between the second connection duct and the first end of the housing.

11. A hydromechanical spring-loaded drive comprising:
an accumulator module for activating a high-voltage power switch, wherein the accumulator module includes:
a pressure-tight housing;
an accumulator piston that protrudes into the housing and is axially movable in the housing between a first end of the housing and a second end of the housing, the accumulator piston comprising:
a head having a first diameter;
the head comprising a terminal surface facing towards the second end of the housing and a circumference peripherally connected with the terminal surface;
a guide strip fastened to the circumference of the head, the guide strip having a second diameter greater than the first diameter, the guide strip configured to contact an inner wall of the housing during an operation of the accumulator module to maintain a gap between the circumference of the head and the inner wall, the inner wall having a third diameter greater than the first diameter; and
at least one pressure-relief groove in the head, the at least one pressure-relief groove disposed around the circumference of the head;

a closure cover that closes the first end of the housing in a pressure-tight manner;
a pair of connection ducts in the housing, for conveying a highly pressurized fluid to a high-pressure duct located outside the housing, such that the highly pressurized fluid is located in the gap between the inner wall of the housing and the head of the accumulator piston during the operation of the accumulator module, and such that the guide strip is maintained between the second end of the housing and the pair of connection ducts when the accumulator piston is in contact with the first end of the housing; and
a spring accumulator coupled to the piston,
the guide strip fastened to the circumference of the head in between the terminal surface of the head and the at least one pressure-relief groove, the accumulator piston further comprising a single through-bore comprising an axial bore portion and a radial bore portion, the axial bore portion axially traversing into the terminal surface of the head and extending on a longitudinal axis of the accumulator piston, the radial bore portion radially traversing through the circumference of the head and not traversing into the at least one pressure-relief groove, the axial bore portion substantially perpendicular to the radial bore portion and in fluid communication with the axial bore portion, the axial bore portion configured to allow the highly pressurized fluid to flow between a base of the housing and the radial bore portion, the radial bore portion configured to allow the highly pressur

Assignees

• Hitachi Energy Switzerland Ag

Inventors

• Robens Niko

Classifications

• H01H3/24

  using pneumatic or hydraulic actuator {(for storing energy in a spring motor H01H3/301)} · CPC title

• F15B2201/21

  using springs · CPC title

• H01H33/40

  using spring motor · CPC title

• H01H3/301

  using a fluid actuator · CPC title

• F15B2201/31

  having rigid separating means, e.g. pistons · CPC title