Piston-cylinder unit and adjustment device with a piston-cylinder unit

Abstract

Piston-cylinder unit (10), in particular for generating or / or providing force for an adjustment movement of a component to be moved, comprising at least: a first piston-cylinder assembly (20) and a second piston-cylinder assembly (30), each having an extendable piston rod (24, 34), wherein the first piston-cylinder assembly (20) and the second piston-cylinder assembly (30) are arranged essentially parallel and opposite to each other, so that their piston rods (24, 34) can be extended in opposite directions, and a mechanical coupling element (70) that connects the first piston-cylinder assembly (20) and the second piston-cylinder assembly (30) to effect a common translational movement, wherein the first piston-cylinder assembly (20) and the second piston-cylinder assembly (30) are fluidically separated from each other.

Description

[0001] The present invention relates to a piston-cylinder unit, in particular for generating an adjustment movement of a moving component with a large stroke and a compact overall length. The invention further relates to an adjustment device comprising such a piston-cylinder unit, and to the use of the unit in a height-adjustable arrangement.

[0002] Particularly in automotive engineering, there is often a requirement to implement an adjustment movement that allows for a particularly large travel (stroke) within a very limited installation space. Conventional gas springs or piston-cylinder assemblies, which are traditionally used for weight compensation of flaps or other moving objects, often cannot meet this requirement because the available installation space is determined by the available pivot points, and the retracted length of conventional gas springs is typically more than half their maximum stroke. To solve this problem, telescopic gas springs are known in the prior art. These consist of several coaxially arranged piston rods that extend sequentially, thus achieving a stroke that exceeds the retracted length of the unit.

[0003] However, these telescopic systems have significant disadvantages. Their design, with multiple telescoping piston rods, results in considerable structural complexity and a large number of sealing points between the individual stages. This not only increases the risk of leaks and reduces service life, but also makes manufacturing complex and expensive.

[0004] Furthermore, due to the different surface area ratios of the piston rods, an undesirable abrupt or unfavorable force curve is evident in the force-displacement diagram of these telescopic systems.

[0005] The task, therefore, is to provide an improved piston-cylinder unit that overcomes the disadvantages of the prior art. In particular, a piston-cylinder unit should be created that achieves a large stroke with a compact overall length, but is simpler in design, more cost-effective to manufacture, more reliable in operation, and exhibits a more uniform force distribution.

[0006] This problem is solved according to the invention by a piston-cylinder unit according to claim 1 or an adjusting device for a movable component according to claim 7.

[0007] Specifically, the problem according to claim 1 is solved by a piston-cylinder unit, in particular for generating or / or providing force assistance for an adjustment movement of a component to be moved, which comprises at least a first piston-cylinder assembly and a second piston-cylinder assembly, each having an extendable piston rod. Furthermore, the first piston-cylinder assembly and the second piston-cylinder assembly are arranged substantially parallel and opposite to each other, so that their piston rods can be extended in opposite directions. A mechanical coupling element is also provided, which connects the first piston-cylinder assembly and the second piston-cylinder assembly to effect a common translational movement, wherein the first piston-cylinder assembly and the second piston-cylinder assembly are fluidically separated from each other.

[0008] The two piston-cylinder assemblies, which are preferably designed as gas springs, are, in other words, coupled to each other in a simple manner. By arranging the piston-cylinder assemblies in parallel, the dead length of most components of the unidirectionally extending piston-cylinder assembly(s) can be reduced when considering the stroke / length.

[0009] In this context, "arranged parallel to each other" means that the longitudinal axes of the piston-cylinder assemblies are essentially parallel to each other.

[0010] The piston-cylinder units are fluidically separated from each other, and there is no fluid connection between their working chambers. This purely mechanical design, using self-contained standard units, drastically reduces complexity compared to telescopic systems, lowering manufacturing costs and significantly increasing operational reliability due to fewer sealing points.

[0011] According to a further preferred embodiment of the invention, a third piston-cylinder assembly is provided, which is arranged essentially parallel to the first and second piston-cylinder assemblies, wherein two of the piston-cylinder assemblies can be extended in a first direction and one of the piston-cylinder assemblies can be extended in a second direction opposite to the first direction. This arrangement allows for flexible adjustment of the force characteristic and can further improve the stability of the unit.

[0012] Preferably, the two piston-cylinder assemblies, which are arranged to extend in the first direction, are arranged on the outside, so that the piston-cylinder assembly, which is arranged to extend in the second direction, is positioned centrally between the two outer piston-cylinder assemblies.

[0013] According to a further preferred embodiment of the invention, the ends of the piston rods of the two synchronized piston-cylinder assemblies, which protrude from the cylinders, are connected by means of a bridge-like connecting element to which a connecting element is attached. The piston-cylinder unit has, for example, two connecting elements, which serve for the preferably articulated connection between the component to be moved and a higher-level assembly.

[0014] The component to be moved could be, for example, a height-adjustable assembly for display and / or switching elements (display, dashboard, control console, etc.). The overarching component in this case is, for example, the vehicle body or a cockpit trim panel attached to it.

[0015] This creates a defined, stable connection point for the two oriented piston-cylinder assemblies and distributes the applied forces evenly between them. Lateral forces are thus eliminated.

[0016] According to a further preferred embodiment of the invention, the mechanical coupling element is designed as a one-piece component, in particular as an injection-molded plastic component. This enables particularly cost-effective and weight-saving production of the coupling element while simultaneously allowing for a high degree of design freedom.

[0017] According to a further preferred embodiment of the invention, the mechanical coupling element has receiving points designed to receive the cylinder ends of the piston-cylinder assemblies in a form-fit and / or force-fit manner. This significantly simplifies the assembly of the unit and reduces manufacturing time.

[0018] According to a further preferred embodiment of the invention, the maximum stroke of the piston-cylinder unit is greater than the overall length of the unit in its fully retracted state. This space-saving feature according to the invention makes the proposed piston-cylinder unit particularly suitable for applications in confined spaces.

[0019] According to a further preferred embodiment of the invention, an adjustment device for a movable component comprises a piston-cylinder unit according to the invention and an electric drive for controlling the adjustment movement. The combination with an electric drive enables precise, automated, and convenient control of the adjustment movement. For example, a known spindle drive can be provided as the electric drive.

[0020] The piston-cylinder unit according to the invention is particularly suitable for use in a height-adjustable arrangement for display and / or switching elements in a motor vehicle. The compact design and large stroke of the unit are ideal for linearly adjusting, for example, large displays, dashboards, or control consoles in the cockpit of a motor vehicle.

[0021] Other applications of the piston-cylinder unit according to the invention are not excluded within the scope of the invention.

[0022] The present invention will be described below with reference to an exemplary embodiment. The drawings, the description, and the claims contain numerous features in combination. A person skilled in the art will expediently consider the features individually and combine them into meaningful further combinations. Thus, one or more exemplary embodiments can advantageously be combined with one another.

[0023] They represent: Fig. 1 a top view of an embodiment of the piston-cylinder unit according to the invention in an extended state; Fig. 2 a side view of the piston-cylinder unit from Fig. 1; as well as Fig. 3 a sectional view along line AA from Fig. 2.

[0024] The Fig. Figures 1 to 3 show a preferred embodiment of the piston-cylinder unit 10 according to the invention, which is provided for generating or / or providing force assistance for an adjustment movement of a component to be moved.

[0025] A power assistance unit for movable components may be desirable if the movable component has a high weight. This weight can be largely compensated for by a power assistance unit, thus enabling improved or more comfortable adjustment of the component.

[0026] In this embodiment, unit 10 comprises three separate, independent piston-cylinder assemblies 20, 30, 40, which are preferably designed as standard gas springs. Each piston-cylinder assembly 20, 30, 40 has a cylinder 22, 32, 42 and a piston rod 24, 34, 44 that can be extended from it.

[0027] The piston-cylinder assemblies 20, 30, 40 each have a piston attached at one end to the piston rod 24, 34, 44 and slidably arranged in the cylinder 22, 32, 42, which divides the fluid-filled cylinder 22, 32, 42 into two working chambers. The piston rod 24, 34, 44 extends through one of the working chambers and through a guide and sealing assembly located at the end of the cylinder 22, 32, 42, which seals the cylinder.

[0028] The piston-cylinder unit 10 has two connection elements 50, 60, which preferably serve as the articulated connection between the component to be moved and a higher-level assembly. The component to be moved can, for example, be a height-adjustable arrangement for display and / or switching elements (display, dashboard, control console, etc.). In this case, the higher-level assembly is, for example, the body or a cockpit trim panel attached to it.

[0029] As shown in the section view along line AA in Fig. As can be seen most clearly in Figure 3, the piston-cylinder assemblies 20, 30, 40 are arranged essentially parallel to each other. In this context, "arranged parallel to each other" means that the longitudinal axes of the cylinders of the piston-cylinder assemblies 20, 30, 40 are essentially parallel to each other.

[0030] The first piston-cylinder assembly 20 and the third piston-cylinder assembly 40 are aligned in the same direction, while the second, centrally located piston-cylinder assembly 30 is aligned in the opposite direction. This means that the piston rods 24, 44 of the piston-cylinder assemblies 20 and 40 extend in a first direction (in Fig. 3 to the left), while the piston rod 34 of the second, centrally arranged piston-cylinder assembly 30 extends in the opposite second direction (in Fig. 3 to the right).

[0031] The individual piston-cylinder assemblies 20, 30, 40 are connected to each other purely mechanically.

[0032] How especially Fig. As can be seen from Figure 3, a mechanical coupling element 70 can be provided for the connection, which is preferably designed as a one-piece component, in particular as a plastic injection-molded component.

[0033] The mechanical coupling element 70 has suitable receiving points designed to receive the cylinders 22, 32, 42 of the piston-cylinder assemblies 20, 30, 40 or their ends in a form-fit and / or force-fit manner, wherein the piston rods 24, 34, 44 each protrude from the end face of the coupling element 70.

[0034] By arranging the piston-cylinder units 20, 30, 40 in parallel, the dead length of most components of the piston-cylinder unit extending in one direction or the piston-cylinder units extending in one direction can be saved in the stroke / length consideration.

[0035] The ends of the piston rods 24, 44 of the first piston-cylinder assembly 20 and the third piston-cylinder assembly 40, which protrude from the cylinders 22, 42 and are positioned in the coupling element 70 in the same direction as described above, are connected by means of a bridge-like connecting element 80. The connecting element 50 is attached to the bridge-like connecting element 80, thereby creating a defined, stable connection point. In particular, lateral forces can thus be eliminated.

[0036] The piston-cylinder assemblies 20, 30, and 40 are completely self-contained fluidically. No exchange of working fluid (e.g., gas or oil) takes place between the individual assemblies. Synchronization of their translational movement is achieved exclusively through the rigid mechanical connection via the coupling element 70 and the bridge-like connecting element 80. When the movable component is adjusted, the piston-cylinder assemblies 20, 30, and 40 can be extended or retracted simultaneously, resulting in a common, linear adjustment movement of the entire piston-cylinder unit 10.

[0037] It should be noted that the second piston-cylinder assembly 30 may be dimensioned differently compared to the other two piston-cylinder assemblies 20 and 40 and does not have to be identical in construction to the other two piston-cylinder assemblies 20 and 40.

[0038] The piston-cylinder unit 10 can be provided as part of an adjustment device which, for example, includes an electric drive to control the adjustment movement. This drive can preferably be an electric spindle drive and enable electric adjustment of the component as an active adjustment element. The electric drive can thus control the movement and hold the piston-cylinder unit 10 in any intermediate position, while the piston-cylinder assemblies 20, 30, 40 support the force required for the movement and compensate for the weight of the component to be moved. In this case, the piston-cylinder unit 10 is a passive adjustment element.

[0039] In addition, suitable damping measures can be provided to prevent an unintentional, abrupt lowering of the component in the event of a failure and a resulting interruption of the force transmission, e.g. due to a failure of connecting parts of the electric drive.

[0040] It is also conceivable that the piston-cylinder assemblies 20, 30, 40 each have a blocking function.

Claims

[1] Piston-cylinder unit (10), in particular for generating or / or providing force for an adjustment movement of a component to be moved, comprising at least: a first piston-cylinder assembly (20) and a second piston-cylinder assembly (30), each having an extendable piston rod (24, 34), wherein the first piston-cylinder assembly (20) and the second piston-cylinder assembly (30) are arranged essentially parallel and opposite to each other, so that their piston rods (24, 34) can be extended in opposite directions, and a mechanical coupling element (70) that connects the first piston-cylinder assembly (20) and the second piston-cylinder assembly (30) to effect a common translational movement, wherein the first piston-cylinder assembly (20) and the second piston-cylinder assembly (30) are fluidically separated from each other. [2] Piston-cylinder unit (10) according to claim 1, characterized by , that a third piston-cylinder assembly (40) is provided, which is arranged essentially parallel to the first piston-cylinder assembly (20) and second piston-cylinder assembly (30), wherein two of the piston-cylinder assemblies (20, 40) are extendable in a first direction and one of the piston-cylinder assemblies (30) is extendable in a second direction opposite to the first direction. [3] Piston-cylinder unit (10) according to claim 2, characterized by , that the ends of the piston rods (24, 44) protruding from cylinders (22, 42) of the two piston-cylinder assemblies (20, 40) in the same direction are connected by means of a bridge-like connecting element (80) to which a connecting element (50) is attached. [4] Piston-cylinder unit (10) according to any one of the preceding claims, characterized by, that the mechanical coupling element (70) is designed as a one-piece component, in particular as a plastic injection-molded component. [5] Piston-cylinder unit (10) according to any one of the preceding claims, characterized by , that the mechanical coupling element (70) has receiving points designed to receive cylinders (22, 32, 42) of the piston-cylinder assemblies (12, 14, 16) in a form-fit and / or force-fit manner. [6] Piston-cylinder unit (10) according to any one of the preceding claims, characterized by , that a maximum stroke of the piston-cylinder unit (10) is greater than a total length of the unit in its fully retracted state. [7] Adjustment device for a movable component, comprising a piston-cylinder unit (10) according to any one of claims 1 to 6 and an electric drive for controlling the adjustment movement. [8] Use of a piston-cylinder unit (10) according to any one of claims 1 to 6 in a height-adjustable arrangement for display and / or switching elements in a motor vehicle.

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