Abstract: Provided is a temperature-driven valve assembly which can be manufactured in a cost-effective and simple manner as well as a gas pressure spring including the valve assembly which enables more reliable and safer operation of the gas pressure spring.

Abstract: In a piston-cylinder assembly comprising a cylinder in which a piston rod is installed with freedom of axial movement and which is filled with a blocking medium, a braking device becomes active when the piston-cylinder assembly moves faster than a defined speed and thus limits the speed to a desired extent. A valve body divides the cylinder into two working spaces, which are connected to each other by at least one flow-through opening. As soon as the defined speed is exceeded, the dynamic pressure in the working space elastically deforms a disk, which has the effect of at least partially sealing off the flow-through opening(s) in opposition to the forces trying to keep them open. The elastic deformation of the disk represents a closing movement relative to the cross section of the flow-through opening(s). The disk takes the form of a valve ring, which is installed in a valve ring groove with a certain freedom of axial movement.

Abstract: In a piston-cylinder assembly comprising a cylinder in which a piston rod is installed with freedom of axial movement and which is filled with a blocking medium, a braking device becomes active when the piston-cylinder assembly moves faster than a defined speed and thus limits the speed to a desired extent. A valve body divides the cylinder into two working spaces, which are connected to each other by at least one flow-through opening. As soon as the defined speed is exceeded, the dynamic pressure in the working space elastically deforms a disk, which has the effect of at least partially sealing off the flow-through opening(s) in opposition to the forces trying to keep them open. The elastic deformation of the disk represents a closing movement relative to the cross section of the flow-through opening(s). The disk takes the form of a valve ring, which is installed in a valve ring groove with a certain freedom of axial movement.

Abstract: A piston/cylinder assembly includes a cylinder and a piston received in the cylinder for axial movement and dividing the cylinder into two working chambers. A first connecting member is affixed to the cylinder and is adapted to connect the cylinder to one of two elements that are movable relative to each other. At least one second connecting member is operatively coupled to the piston, extends through an opening in the cylinder, and is adapted to connect the piston to the other of the two elements. The opening has a length axially of the cylinder that is not less than the length of the stroke of the piston.

Abstract: A detent device for locking first and second elements that are movable relative to one another includes a first subassembly connected to a first element and a second subassembly connected to the second element. A first locking mechanism of the detent device can be controlled at will by use of an actuating mechanism. The first locking mechanism is subordinated to a second locking mechanism that acts independently of the first locking mechanism as soon as a threshold value of the relative speed of the two subassemblies of the detent device is exceeded. The second locking mechanism includes a first locking element and a second locking element, the first locking element being functionally associated with the first subassembly and the second locking element being functionally associated with the second subassembly. The first and the second locking elements form a clutch. In addition, the locking mechanism can also have two states of locking actuation.

Abstract: A pressurized gas spring, which exerts an expulsion force on the piston rod entailing a maximum extension velocity of the piston rod, includes braking means effective at a velocity of motion due to external forces above the maximum extension velocity for limiting the velocity of motion to a desired measure.

Abstract: A vertically adjustable column, in particular for chairs or tables, includes a pedestal tube having a coaxially arranged lengthwise adjusting element, e.g., a gas spring, and a rotational fixation profile engaging a counterpart profile extending parallel to the longitudinal centerline of the pedestal tube. The rotational fixation profile and the counterpart profile are operatively arranged between the pedestal tube and the lengthwise adjusting element, and one of the profile parts is arranged in series with the lengthwise adjusting element.

Abstract: A pneumatic strut for use as an opening power assist mechanism for a motor vehicle tailgate has a piston rod extending from a piston contained within a cylinder. The piston separates the cylinder into two work chambers, each containing a gas charge under pressure. A bypass opening is active to connect the work chambers during the initial opening displacement of the tailgate to automatically open the tailgate through a first opening angle range. A second valve can be externally actuated to connect the two work chambers to further selectively open the tailgate into a second opening angle range. To close the tailgate, a third, directionally dependent valve can automatically connect the two work chambers during the closing displacement of the tailgate.

Abstract: A column unit, in particular a chair column unit, including a base tube (310) and a pneumatic spring (318), further comprises an axially movable guide bushing (314) which is inserted in an axially movable manner in the upper end (310b) of the base tube (310), and which encloses an axially movable part (318b) of the pneumatic spring (318). An exit movement of the guide bushing (314) can be effected, e.g., by driver- or pusher-stops (326, 314g). The exit movement is restricted by pullout-restricting stops (316, 312g) which are releasable for the disassembly of the column unit.

Abstract: According to an illustrative example of the invention, a chair column comprises a base tube with a support plate. A gas spring is accommodated within the base tube. The piston rod of the gas spring is supported on the base tube by a ball bearing. The cylinder of the gas spring is guided at the upper end of the base tube by a guiding sleeve. The guiding sleeve is telescopical with respect to the base tube in response to outward and inward movement of the cylinder with respect to the base tube such that a full satisfactory guiding function is maintained between the cylinder and the base tube, even when the cylinder is in its uppermost position.

Abstract: According to an illustrative example of the invention, a gas spring is combined with a telescopic tube which is axially slidable on the cylinder of the gas spring. The piston rod and the telescopic tube are provided at the respective most remote ends thereof with fastening eyes. The telescopic tube can be fixed in a plurality of positions with respect to the cylinder. For such fixation, the cylinder is connected with a carrier within the telescopic tube between opposite end walls of the cylinder and the telescopic tube. A locking bolt is guided within the carrier in a direction transverse to the axis of the telescopic tube. The locking bolt is engageable with a corresponding plurality of openings in the telescopic tube. The locking bolt is biased by a spring into an engagement position with respect to a respective opening and can be released from such engagement by being inwardly pressed by an operator.

Abstract: According to an illustrative example of the invention, a gas spring comprises a cylinder which is closed at both ends thereof. A piston is provided within the cylinder and separates two working chambers within the cylinder. The working chambers are filled with a pressurized gas. The piston is connected with a piston rod which extends axially through one end of the cylinder. The working chambers can be selectively connected or separated from each other through an axial channel extending through the piston. This axial channel accommodates a valve pin. The valve pin is axially movable by an actuating rod accommodated by an axial bore of the piston rod. The piston is in sealing engagement with an inner circumferential face of the cylinder. The valve pin is in sealing engagement with the channel. The piston is provided with an elastic covering layer, which covering layer provides both the sealing engagement of the piston with the cylinder and the sealing engagement of the valve pin with the piston.

Abstract: According to an illustrative example of the invention, a motor vehicle comprises a basic frame. A compartment is defined within this basic frame. This compartment is intended for receiving an engine or for receiving luggage. The compartment is provided with a lid which is pivotable about a horizontal axis. For facilitating opening and closing of the lid, a gas spring is in operative connection between the basic frame and the lid. A light source is provided for illuminating the compartment when opened. This light source is mounted on the gas spring.

Abstract: According to an illustrative example of the invention, a gas spring comprises a cylinder and a piston rod. The piston rod is axially movable with respect to the cylinder and has a fastening eye mounted on the outer end of the piston rod. A tubular protection member surrounds an end portion of the cylinder adjacent to the end of the cylinder which is passed by the piston rod. The other end of the protection tube surrounds a holding disk fixed to the piston rod adjacent to the fastening eye. The protection tube and the piston rod define an air space therebetween. The air space is substantially tight against a liquid treating agent, such as a lacquer. On the other hand, the air space is in air flow connection with the surrounding atmosphere so that in response to axial movement of the piston rod with respect to the cylinder, excesssive pressure within the air space is prevented.

Abstract: In a gas spring, the piston rod extends through one end of a container. Sealing rings are provided at this end of the container. These sealing rings are in sealing engagement with the piston rod and possibly also in sealing engagement with the inner surface of the container. Axially subsequent sealing rings are made of different caoutchouc materials. These different caoutchouc materials have different coefficients of permeation.

Abstract: According to an illustrative example of the invention a gas spring has adjacent one end thereof an axially extending control pin. This control pin is prestressed towards an outer position and can be pushed inwards for opening a valve, which valve is provided in the passage between two working chambers established by a piston, said piston being fixed to a piston rod. When the pin is in its outward position, the gas spring is locked in the respective axial length. When the control pin is moved inwards, the axial length of the gas spring can be varied. The gas spring is intended for combination with a chair or table column. In combining the gas spring with a chair, the upper end of the gas spring cylinder is fixed to the lower side of the seat plate. The lower side of the seat plate is provided with a manipulating level. The manipulating lever engages the outer end of the control pin through a telescopic arrangement of control members or adapter elements.

Abstract: A gas spring is provided in an illustrational example between a framework and a trunk cover of a motor vehicle for compensating for the weight of the trunk cover during movement of said trunk cover. The gas spring is hinged to the framework and to the trunk cover. For eliminating the spring force action on the hinge between the trunk cover and the gas spring in the closed position of the trunk cover, the part of the gas spring hinged to the trunk cover is supported on the framework, when the trunk cover is in its closed position. Alternately, the gas spring is locked when the trunk cover is in its closed position.

Abstract: In a gas spring the piston rod is guided through one end of a container. Adjacent to this one end two sealings are provided in axial direction one behind the other, namely an axially outer sealing and an axially inner sealing. A liquid chamber is defined between the axially outer sealing and the axially inner sealing. The axially inner sealing comprises a sealing ring of elastomeric material. This sealing ring comprises a radially outer root portion and a radially inner lip portion. The root portion engages an internal circumferential surface of the container tube. The lip portion engages an external circumferential surface of the piston rod. The axial dimension of the root portion is substantially larger than the axial dimension of the lip portion. The sealing ring may be deflected by pressure differences on both sides of the sealing ring such that a fluid exchange is possible between both axial sides of the sealing ring when the pressure difference exceeds a predetermined value.

Abstract: A positioning device is e.g. used for positioning the door of a motor vehicle in an opened position. The positioning device comprises e.g. a cylinder and a piston rod which extends inward and outwards of the cylinder through one end thereof. A flank face is provided at the inner wall surface of the cylinder. The piston rod carries a piston. The piston is provided with a counter-arresting ring which engages the flank face in a predetermined position. When the piston passes across the arresting flank of the cylinder, the counter-arresting ring is moved radially inwards with respect to the axis of the piston rod against elastic resistence. So, an increased resistance occurs against the axial movement of the piston rod with respect to the cylinder. This increased resistance against axial movement positions the door with respect to the body frame of a motor vehicle in a predetermined opened position and avoids that the door is closed unintentionally.

Abstract: A positioning device is used for the positioning of a chair seat as to its inclination, or for positioning a back-rest member of a chair. The positioning device is constructed such as usual hydropneumatic springs which can be locked by closing a passage connected to working chambers on both sides of a piston. The working chambers are filled with an operating liquid. In order to adapt the biasing force of such a positioning device, one of the working chambers is conneced with a force-measuring device, which force measuring device is provided within the force transmission path of the respective chair column. The force measuring device comprises a measuring space filled with operating liquid, and this operating liquid is in liquid connection with one of the working chambers.