Hydac Technology Corporation

Walter Dorr

Herbert Baltes

Peter Kloft

A safety device for containers pressurized with gas safeguards the gas side of the working chamber of hydraulic accumulators. A relief apparatus () reduces an elevated gas pressure in the container () caused by heat. The relief apparatus () is a component loaded under the influence of a shear force or compressive force. The shape change of the component under the influence of heat on the safety device () in a space () closed to the outside occurs such that a fluid-conducting connection () from the inside of the container () to the outside in the direction of the surroundings is enabled.

Safety device against excess temperature

A dual piston accumulator, in particular for a hydrostatic hybrid drive system for vehicles, replaces a high pressure hydro accumulator and a low pressure hydro accumulator. Inside a single accumulator housing () extending in the axial direction in a single piece over a high pressure part () and a low pressure part (), an accumulator piston () defines a high pressure-sided fluid chamber () and a low pressure-sided fluid chamber (). Both chambers border an intermediate piece () separating the high pressure side () from the low pressure side (). A common piston rod () extends through the intermediate piece for both accumulator pistons (). The wall width of the housing () corresponding to the high pressure part () is greater than the opposite reduced wall width corresponding to the low pressure part ().

Dual piston accumulator

A method produces piston-type accumulators, including an accumulator housing () and a separating piston, which can be displaced in a longitudinal direction inside the accumulator housing () and separates two working spaces located in the housing. One end face of the accumulator housing is sealed by cover part (). The cover part () is fixed on one side () via the free longitudinal edge () of the accumulator housing (). The edge is displaced towards the cover part (), such that a functionally and positionally secure connection of a cover part is ensured within the housing of a piston-type accumulator without using standard threaded connections.

Method for the production of piston-type accumulators

A piston-type accumulator has: a) an accumulator housing in the form of a cylinder tube () made of magnetizable material, which defines an axial direction of the housing; b) a piston (), which can be axially displaced over a stroke path inside the cylinder tube () and which forms a moving separating element that, inside the accumulator housing, separates two working spaces (and) from one another; c) a magnet arrangement (), placed on the piston () and generating a field on the wall of the cylinder tube (), and; d) a magnetic field sensor device located on the exterior of the cylinder tube () and having at least one Hall sensor (). The Hall sensor is mounted on the exterior of the cylinder tube () and responds to the field generated by the magnet arrangement () on the piston () to determine the position of the piston () along the stroke path.

Piston-type accumulator

A hydraulic accumulator includes an accumulator housing () formed of a non-magnetizable material and defining an axial direction of the housing. A separating element () can be axially displaced in the accumulator housing () and separates two working chambers () from each other in the accumulator housing (). A field-generating magnetic configuration () is arranged on the separating element. A series of magnetic field sensors () are arranged on the outer side of the accumulator housing (), extend along the path of the axial movement of the separating element () and react to the field of the magnetic configuration () on the separating element () to characterize its position along the series of magnetic field sensors ().

Growing community of inventors

Völklingen, Germany

Walter Dorr