DE102022128174B4 - Bowden cable - Google Patents

Abstract

Bowden cable for transmitting compressive and/or tensile forces and/or mechanical movements, comprising a core (1) which is surrounded by a guide tube (2) except for its two end regions, wherein the guide tube (2) has a guide tube end piece (3) at at least one of its two ends, to which a sealing element (6) is assigned, wherein the sealing element (6) is arranged in the end of the guide tube end piece (3) facing away from the guide tube (2), and wherein the sealing element (6) surrounding the core (1) is positioned visibly from outside the guide tube end piece (3) at the end of the guide tube end piece (3) facing away from the guide tube (2), characterized in that an additional guide device (5) for the core (1) of the Bowden cable is held on the guide tube end piece (3) at an outer distance from an end of the guide tube end piece (3), which end faces away from the guide tube (2).

Description

The invention relates to a Bowden cable for transmitting compressive and/or tensile forces and/or mechanical movements, comprising a core that is surrounded by a guide tube except for its two end regions, wherein the guide tube has a guide tube end piece at at least one of its two ends, to which a sealing element is assigned. The sealing element is arranged in the end of the guide tube end piece facing away from the guide tube, and the sealing element surrounding the core is positioned at the end of the guide tube end piece facing away from the guide tube and is visibly positioned from outside the guide tube end piece.

Bowden cables are used in a variety of applications, for example in household appliances for the emergency release of locks, in plumbing for operating valves, and also in the automotive industry, e.g., for operating parking brakes, unlocking seats, trunk lids, fuel filler caps, etc. The ends of the guide tube, or the guide tube end pieces, can be exposed to harsh environmental conditions. The ingress of dirt and moisture into the interior of the Bowden cable can lead to stiffness, corrosion, and blockages. For this reason, it is common practice to seal the interface between the inner tube and the guide tube using sealing elements.

Here, bellows or grommets made of elastomeric materials are used. Such sealing elements are located externally and are therefore exposed to all environmental influences, whereby high demands, such as stone impacts, strong jet water, high-pressure jet water, possibly also at high temperatures, can lead to the failure of the external sealing elements.

Known internal sealing elements are located within the guide tube end piece and are thus protected from environmental influences. However, a disadvantage is that it is not possible to tell whether a sealing element has been installed or not once the Bowden cable is fully assembled.

However, suggestions for overcoming this disadvantage have been made in the prior art. In one example from the DE 85 10 490 U1 A well-known Bowden cable is to be fitted with a space-saving and damage-resistant seal in a cost-effective manner. The Bowden cable comprises a hose attached to a bearing head at one end, a core extending longitudinally through the hose and the head, and an elastic seal attached to the head, which seals by sliding on the core at least at its end furthest from the hose. The Bowden cable is characterized by the fact that the seal is arranged in a cavity surrounding the core and open to the end face of the head opposite the hose, and/or as a plate on the end face in the area where the core exits the head.

The text further describes DE 31 08 046 A1 A Bowden cable with a flexible guide featuring an integral or separate inner lining made of plastic and a force-transmitting cable axially displaceable within the guide. At least at one end of the Bowden cable, an end section of the inner lining protrudes from the guide or the surrounding layer(s) of the guide. A flexible sealing bushing made of elastically deformable material is located on the guide; part of its length seals the protruding end of the inner lining, and another part seals the cable tightly.

In the DE 697 26 331 T2 This document describes a protective cap system for a control cable, such as a bicycle control cable, with an inner cable moving within a cable housing, preventing contaminants from entering the control cable. The protective cap comprises a first section dimensioned to fit over the cable housing and a second section dimensioned to fit snugly over the inner cable. The second section is made of a flexible material, allowing it to conform to any curve of the inner cable while maintaining a tight seal. The cable housing can be the outer casing of the control cable or another structure that fits over the outer casing or the cable. In the latter case, the first section of the protective cap can have an outer diameter dimensioned to fit within an inner section of the cable housing.

Another one from the DE 198 02 442 A1 A known cable cap for a cable sliding in a flexible tube comprises a tubular housing closed by a base with an opening for the passage of the cable. An extension of the tubular housing is provided on its inner surface with a lip seal and on its outer surface with at least one groove connected to the inner surface by channels, the material of the lip seal passing through the channels.

The DE 38 14 874 reveals an end cover for an external cable used on a bicycle A control wire or wire pull runs through a space between the base of a cover body and a holder for the external cable, which is to be inserted into the cover body. A sealing element is located in this space to prevent dirt adhering to the outer surface of the control wire from entering the external cable.

Finally, from the DE 10 2016 117 437 A1 A bicycle adjustment module for actuating an adjustable bicycle component is known. The bicycle adjustment module comprises an adjustment element and a Bowden cable with a Bowden cable housing and a core, which is movably guided within the Bowden cable housing to transmit an adjustment force. The core is connected to the adjustment element at a first end. The Bowden cable housing is receptacled in an end piece at least at a first end. Furthermore, a one-piece seal is provided, which in a first region encloses the first end of the Bowden cable housing and in a second region extends over a portion of the core protruding from the Bowden cable housing and seals against the core. The seal is designed so that, in the state where the cable is receptacled, it is pressed against the Bowden cable housing in the first region by an end piece.

In addition, depending on the design of the compression between the core and the seal, as well as the position of the seal within the guide tube end piece, pivoting movements of the core can cause it to lift off one side of the seal, creating a gap that results in a leak.

The invention is based on the objective of preventing a shift in the mind's position relative to the poetry.

This task is solved by holding an additional guide device for the core of the Bowden cable on the end of the guide tube, spaced outwards from one end of the guide tube, which end faces away from the guide tube.

The invention offers the advantage that the seal always rests against the guide tube end and the core, without causing leaks.

The sealing element, which is located in the end of the guide tube facing away from the guide tube and is visibly positioned at the end of the guide tube facing away from the guide tube, solves the problem of ensuring a safe, verifiable seal between the core and the guide tube or guide tube end piece, which does not allow leaks even when the core is twisted and also enables smooth movement of the core.

The placement of the seal within the guide tube end ensures that the end of the guide tube protectively surrounds the seal, thus guaranteeing maximum sealing effectiveness. The visible sealing element eliminates any doubt as to whether a sealing element has been installed in the guide tube end or not.

An advantage is that the sealing element has at least one zone which surrounds the core in linear contact.

With a full-surface guide, the core can be difficult to operate. Linear contact points, or two or more linearly arranged contact points, ensure smooth movement of the core.

It has proven advantageous that the additional guide device causes an angular deflection of the core guide relative to the guide in the sealing element of the guide tube end piece of < 10°, preferably < 5°, particularly preferably 0°.

This prevents any tilting or only such a slight tilting between the core and the seal that the tightness of the Bowden cable is not compromised.

It is advantageous for the core to be formed by a plastic-coated rope, preferably a plastic-coated steel rope.

Conventional steel cables made from individual wires often have small gaps between them, which seals cannot always completely close. The plastic sheathing fills these gaps, giving the inner cable a smooth, gap-free surface that can be optimally sealed. Furthermore, capillary action between the individual wires can draw moisture from the inner cable past the sealing element and into the Bowden cable. The plastic sheathing prevents moisture from penetrating the steel cable into the Bowden cable. The plastic sheathing also ensures that the inner cable runs particularly smoothly in both the sealing element and the guide tube.

• 1 einen erfindungsgemäß ausgestatteten Endbereich eines Bowdenzuges, und
• 2 ein geschnittenes Prinzipbild durch den erfindungsgemäßen Endbereich eines Bowdenzugs.

The invention is explained in more detail with reference to a drawing. The drawing shows

• 1 an end section of a Bowden cable equipped according to the invention, and
• 2 a cutaway schematic diagram through the end region of a Bowden cable according to the invention.

1 Figure 1 shows one end of a Bowden cable, which has a core 1 guided in a guide tube 2. A guide tube end piece 3 is arranged at the end of the guide tube 2; the end of the Bowden cable (not shown) may also regularly have a guide tube end piece. Two webs 4 are arranged on the guide tube end piece 3, which hold an additional guide device 5. The sealing element 6 is visible on the guide tube end piece 3, so the question of whether a sealing element 6 is installed or not does not arise.

In 2 The sealing element 6 is visible within the guide end piece 3. The sealing element 6 has two annular sealing lips 7 which surround the core 1 in line contact. This line contact ensures smooth movement of the core 1.

The inner cable 1 is formed by a steel cable 8, which is surrounded by a plastic sheath 9. This ensures that the gaps between the individual wires are filled by the plastic sheath 9. Moisture that enters the Bowden cable via capillary action between the individual wires, past the sealing element 6 and through the inner cable 1, is also prevented from entering the Bowden cable by the plastic sheath 9. Furthermore, the plastic sheath 9 allows for smooth movement of the inner cable 1 both between the sealing lips 7 and within the guide tube 2.

Reference symbol list

1

Soul

2

Guide tube

3

Guide tube end piece

4

footbridges

5

additional guide device

6

Sealing element

7

Sealing lips

8

steel cable

9

plastic coating

Claims (5)

Bowden cable for transmitting compressive and/or tensile forces and/or mechanical movements, comprising a core (1) surrounded by a guide tube (2) except for its two end regions, wherein the guide tube (2) has a guide tube end piece (3) at at least one of its two ends, to which a sealing element (6) is assigned, wherein the sealing element (6) is arranged in the end of the guide tube end piece (3) facing away from the guide tube (2), and wherein the sealing element (6) surrounding the core (1) is positioned visibly from outside the guide tube end piece (3) at the end of the guide tube end piece (3) facing away from the guide tube (2), characterized in that an additional guide device (5) for the core (1) of the Bowden cable is held on the guide tube end piece (3) at an outer distance from an end of the guide tube end piece (3), which end faces away from the guide tube (2). Bowden cable Claim 1 , characterized in that the sealing element (6) has at least one zone which surrounds the core (1) in a linear contact pattern. Bowden cable Claim 1 or 2 , characterized in that two webs (4) are arranged on the guide tube end piece (3) which hold the additional guide device (5). Bowden cable after one of the Claims 1 until 3 , characterized in that the additional guide device (5) causes an angulation of the core guide relative to the guide in the sealing element (6) of the guide tube end piece (3) of less than 10°, preferably less than 5°, particularly preferably 0°. Bowden cable after one of the Claims 1 until 4 , characterized in that the core (1) is formed by a rope with plastic sheathing, preferably a steel rope (8) with plastic sheathing (9).