Release systems are used to operate locking gas springs. When the release pin of the gas spring is pressed, the internal valve opens and the piston rod can move in or out. Once the release mechanism is released, the valve closes again and the gas spring locks in its current position.

Depending on the installation, the gas spring can be operated directly using a lever or remotely using a Bowden cable. This allows flaps, backrests, seats, tables, treatment couches and other movable components to be adjusted comfortably and continuously.

Use the product table above to select a suitable release system by connection thread, dimensions, lever length or Bowden cable length.

Direct Release Lever or Bowden Cable?

Direct Release Lever

A direct release lever is mounted directly onto the release connection of the locking gas spring. Operating the lever presses the release pin and unlocks the gas spring.

This version is particularly suitable where:

the gas spring is easily accessible,
the adjustment is to be operated directly at the mechanism,
a compact and simple solution is required,
the operating point does not need to be separated from the gas spring.

A longer lever generally provides greater mechanical advantage and can reduce the required hand force. However, it also requires more installation and movement space.

Bowden Cable Release System

A Bowden cable transfers the operating movement from a remote hand or foot lever to the release mechanism of the gas spring. It consists of a movable inner cable and a flexible outer casing.

This version is particularly suitable where:

the gas spring is concealed or difficult to access,
the operating point must be positioned away from the gas spring,
the control must be located in an ergonomically suitable position,
the release mechanism is installed behind a cover or panel.

The required Bowden cable length depends on the distance between the operating lever and the gas spring, as well as the intended cable routing.

Meaning of the Specifications in the Product Table

Specification	Meaning
Gas spring thread M	Connection thread used to mount the release system onto the locking gas spring. The thread size and design must match the gas spring.
Length R	Overall length of the release connection according to the product drawing. This dimension influences the required installation space at the end of the gas spring.
Material thickness T	Thickness of the component in the specified area. This value is particularly relevant to the lateral space required by direct lever versions.
Hole diameter H	Diameter of the mounting or connection hole shown in the product drawing. Its exact function depends on the individual design.
Lever length L	Effective length of the direct release lever. It influences the operating travel, required installation space and mechanical advantage.
Bowden cable length S	Overall length of the Bowden cable. It must suit the distance and routing between the operating point and the gas spring.
Material	Material or material combination of the release system, such as steel and plastic.
Total stock	Total quantity of the article currently held in stock.
Available immediately	Quantity currently available for immediate dispatch.

Not every table dimension is required for every design. A direct lever, for example, is specified by its lever length, while the Bowden cable length S is the relevant value for a remote release system.

How to Select the Right Release System

Proceed in the following order:

Check the gas spring: Verify the design, release pin and connection thread of the locking gas spring.
Define the operating point: Decide whether the gas spring should be operated directly or from a remote position.
Measure the installation space: Consider the length of the release head and the movement space required by the lever.
Select the lever or Bowden cable length: The lever must be easy to reach. The Bowden cable must be long enough but should not be unnecessarily long or routed in tight loops.
Consider the operating force: The required force depends on the locking gas spring, its extension force and the lever ratio.
Check the release travel: The release pin must be pressed far enough for the valve to open completely.
Ensure reliable return: After release, the pin must return fully to its original position so that the gas spring locks securely.

The release system and gas spring must be considered as one functional unit. A system that can be mounted mechanically is not necessarily adjusted correctly.

Routing a Bowden Cable

A Bowden cable should be routed as straight as possible and with large bend radii. Tight bends increase friction and may result in a higher operating force or prevent the cable from returning completely.

The following should be considered during installation:

avoid sharp bends and tight loops,
maintain sufficient clearance from moving or hot components,
secure the outer casing correctly,
prevent the cable from being crushed by clamps or covers,
allow sufficient movement for the application,
protect the cable against dirt, moisture and mechanical damage.

The inner cable must not remain under excessive preload. Otherwise, the release pin may remain partially pressed and the gas spring may fail to lock reliably.

Excessive free play, on the other hand, may prevent the required release travel from being reached.

Installation and Adjustment

Before installation, the movable component must be secured against unintended lowering or movement.

For reliable operation, we recommend:

mounting the release system fully onto the intended thread,
positioning the lever so that it remains free to move throughout its complete travel,
routing Bowden cables without tension and with sufficiently large bend radii,
testing the release mechanism initially without a high load,
subsequently testing the system throughout the complete adjustment range,
checking that the gas spring locks immediately after the control is released.

The release pin must not be shortened, extended, ground or otherwise modified using tools. The release system must also not be used as a mechanical end stop.

Functional Check

After installation, the application should be operated several times throughout its complete range. Check the following:

Does the valve open when the control is fully operated?
Can the component be adjusted smoothly?
Does the gas spring lock immediately after release?
Does the operating lever return completely?
Does the Bowden cable remain free from tension, kinks and crushing in every position?
Does the release system collide with adjacent components?

If the gas spring continues to move after the control has been released, first check whether the release system is still applying slight pressure to the release pin.

Typical Applications

Release systems for locking gas springs are commonly used in:

seat and backrest adjustment systems,
medical treatment couches and therapy equipment,
height- and angle-adjustable tables,
ergonomic workstations,
machine covers and control panels,
furniture and adjustable beds,
rehabilitation and care products,
vehicle and special-purpose constructions.

Suitable gas springs can be found in our locking gas springs range.

Further information on operation, selection and installation can be found in our Gas Spring FAQ.

Frequently Asked Questions About Release Systems

When do I need a Bowden cable?

A Bowden cable is useful when the gas spring is not directly accessible or when the operating control needs to be located at a remote position.

Which Bowden cable length is correct?

The cable must be long enough for the complete routing, including the required bend radii. An unnecessarily long cable may make installation and operation more difficult.

Why does the gas spring not lock after releasing the control?

The Bowden cable may be under excessive preload or the lever may not be returning completely. As a result, the release pin may remain partially pressed.

Can every lever be combined with every locking gas spring?

No. The connection thread, release travel, operating force and installation space must be compatible.

Can the gas spring be adjusted without a release system?

The release pin can, in principle, be pressed directly. However, a suitable release system is required for safe, repeatable and ergonomic operation.