WO2018065377A1

WO2018065377A1 - Rotary feedthrough for lines

Info

Publication number: WO2018065377A1
Application number: PCT/EP2017/075006
Authority: WO
Inventors: Georg Theiss
Original assignee: Igus Gmbh
Priority date: 2016-10-04
Filing date: 2017-10-02
Publication date: 2018-04-12
Also published as: DE202016105507U1

Abstract

The invention relates to an uninterrupted rotary feedthrough (10) which is of straightforward construction, has a long service life and a low level of resistance, and is intended for cables, hoses or the like. The rotary feedthrough has a housing, with two housing parts (12A; 12B) which can be rotated relative to one another around an axis of rotation (A), and, defined around the axis of rotation (A), a substantially cylindrical accommodating space (13A; 13B). The one or more lines run in uninterrupted fashion therein by way of two sections (14A; 14B), which are curved around the axis of rotation (A), and a deflection bend (15), which connects said sections (14A; 14B), is curved around the axis of rotation (A) and runs in a substantially U-shaped manner around a deflection axis perpendicular to the axis of rotation. The housing has a cylindrical outer wall (16A; 16B). The cylindrical outer wall (16A; 16B) predetermines the curvature of the sections (14A; 14B) and of the deflection bend (15) around the axis of rotation (A) and is formed at least over a corresponding axial portion of in each case one of the housing parts (12A; 12B).

Description

Rotary feedthrough for cables

The invention generally relates to a rotary feedthrough for at least one electrical, pneumatic and / or

hydraulic line, e.g. Cables, hoses or the like

Endless rotatable rotary unions are known from hydraulics and pneumatics. For electrical power or signals, e.g. Slip rings or sliding contacts for endless rotation transmission well known. In both cases, an interruption of the line is mandatory in order to connect the interfaces on both sides of the rotary feedthrough or the slip ring.

In contrast, the invention relates specifically to a

uninterrupted but angle limited

Rotary feedthrough for at least one flexible line, i. a rotary union, which allows a limited rotation angle without interruption of the line (s).

For flexible flat electrical cable is such

Rotary feedthrough from the patent DE 40 04 233 AI known. This rotation angle limited rotary feedthrough has a housing with two about a rotational axis relative to each other rotatable housing parts. The housing defines a substantially cylindrical with respect to the axis of rotation

Recording room for an uninterrupted course of the

Flat cable with two curved around the axis of rotation and dreams one of these dreams connecting bend or U-shaped turnaround. This is curved about the axis of rotation and about a vertical deflection axis, bent substantially U-shaped. The first housing part forms a cylindrical outer wall, which the curvature of the strands and the

Deflecting bend around the axis of rotation dictates, so that, depending on the angular position, one strand lengthens and the other strand shortened. The second housing part forms a

disc-shaped lid, which limits the receiving space axially or frontally.

A disadvantage of this rotary feedthrough u.a., That in each case a part of the one strand and the entire

Deflection arc on the inside of the outer wall is slidably guided and therefore due to friction wear or

Resistance arises.

An object of the present invention is therefore to propose a generic uninterrupted, rotation angle limited rotary feedthrough, in which the wear or friction resistance is reduced. Another object is to optionally an axial or tangential Einbzw. Output of the line (s) to allow both parts of the housing, preferably at the same time more compact

Construction.

This object is achieved in a

Rotary feedthrough according to the preamble of claim 1 already achieved in that each housing part each forms a substantial axial portion of the cylindrical outer wall. The axial dimension of the portion of the outer wall is at least dimensioned so that each of the two housing parts in each case receive one of the two curved strands in itself and can lead according to the curved course. This already prevents one of the two dreams during the relative rotation of the

Outside wall can generate friction. So that can be achieved be that only part of the deflection arc in

is relatively movable arrangement with respect to the outer wall, along which the deflecting arc radially supported during relative rotation of the housing parts or extends. The strands, however, each rotate synchronously with the corresponding housing part and are thus immobile relative to this housing part. Thus, the wear is reduced and achieved a more common rotary feedthrough.

In addition, a certain axial longitudinal extension of the housing parts allows the provision of special connectors, which optionally have a tangential or axial input or

Allow execution of the line (s).

In an advantageous embodiment, each forms

Housing part in each case in relation to the axial height in

Substantially half of the outer cylindrical wall, i. the interface between both relatively rotatable

Housing parts is approximately centered with respect to the axial height of the housing. This will reduce the friction of the

Deflection arc on the outer wall on the unavoidable

Minimum reduced. In addition, depending on the overall height with reduced friction allows at

consistent design of one or both dreams in the initial position over one or more turns

helical in order to obtain larger angles of rotation. For the latter purpose, however, in addition to the two housing parts, a further, third housing part may be provided, which in the manner of an intermediate ring only one

further axial portion of the cylindrical outer wall provides. Accordingly, the height of the two end-side housing parts in the range of about 20% to 50% of the total height. In a particularly simple way

Embodiment without such an intermediate ring, however, is the interface plane (perpendicular to the axis of rotation)

technically centered in relation to the overall height. The two housing parts are preferably made of plastic, for example by injection molding or 3D printing.

In the preferred case of only two housing parts, each of the two housing parts is preferably substantially

cup-shaped, one-sided open half-shell with a

executed frontal lid. Both housing parts preferably have an interface plane

mirror-symmetric basic shape. The housing parts can be made as one-piece or one-piece plastic parts.

Each housing part may have a coaxial to the outer wall cylindrical inner wall, said outer wall and inner wall defining an annular receiving space in the form of a hollow cylindrical volume. As a result, a defined routing is specified, wherein the radius of the inner wall analogous to the radius of the deflection arc the

permissible radius of curvature of the guided line (s) for protection purposes or for long-term durability not

should fall below. The inner wall itself in turn can be provided with a frontal support disk, with a coaxial opening, by means of which the axis of rotation of the rotary feedthrough is specified. Both the inner wall and the outer wall are preferably circular-cylindrical in relation to the axis of rotation.

In a development which optionally allows an axial or tangential input or output of the line (s), at least one housing part has a frontally and radially opening recess. In this recess can optionally be arranged a connector for axially directed passage or a connector for radially directed passage of the lines. The connector preferably comprises a strain relief for the line (s). In a further development for reducing wear in relation to the line (s) itself, the rotary feedthrough may further comprise a tubular casing, in particular a corrugated hose, for receiving and guiding the one or more lines. The corrugated hose in this case predetermines or follows this course with two convolutions curved around the axis of rotation and a deflecting arch connecting these convolutions.

If connecting pieces are provided on both sides, the corrugated hose can expediently by one of each

Connectors with the corresponding housing part

rotatably connected, in particular be clamped to the respective housing part.

Especially with large diameters and / or with relatively rigid lines, a ring-like support insert can be rotatably received in the receiving space, wherein the

Support insert has one of the bend of the Umlenkbogens adapted deflection surface and two opposing axially directed support surfaces which hold the strands at an axial distance from each other. The use of such

Support insert is particularly advantageous in combination with a hose-like envelope, for example, the aforementioned corrugated hose for further protection of the guided lines. It is especially a conceivable

Kinking of the lines within the receiving space with

Safety excluded. By suitable choice of material, in particular for the support insert, also a particularly low-friction pairing between support insert and the

additional, tubular envelope can be achieved.

The support insert may have rotation stops on which it is entrained by relative rotation of a housing part of this, for. about a cooperative

Driver or stop. This also ensures a controlled, predefined movement of the deflection arc.

It can be provided in the rotary union rotational stops be limited by which the relative rotation angle to an angle in the range of 270 ° to 540 °. The

Rotation angle limitation can also result from the existing in the receiving space total length of the hose-like envelope or lines. As an alternative to small angles of rotation, it is thus also possible to realize larger angles of rotation by moving at least one of the strands in the receiving space

helical over at least one or more full

Revolutions runs. It goes without saying that, depending on the angular position, one strand lengthens and the other strand shortens, i. that the number of optionally provided turns or spirals is divided depending on the rotational angle position on both dreams.

For user-friendly use or

Functional extension, at least one housing part outside on its cylindrical outer wall a rotation angle scale for reading the angular position relative to the other

Have housing part.

The rotary feedthrough according to the invention allows it

In particular, at least one electrical cable and / or a hydraulic or pneumatic hose to perform therein without interruption, which losses or leakage risks are significantly reduced.

For applications in which relatively large angles of rotation are necessary, the invention allows a compact and inexpensive arrangement comprising at least two coaxially successive rotary unions, e.g. for relative rotation between two machine parts over a rotation angle of more than 540 °. Further features of the invention will become apparent from the

attached figures, on the basis of which preferred

Embodiments of the invention below without

Limitation of the generality of the above description be explained. In the figures, like

Reference numerals identical or functionally identical elements. Herein show:

FIG. 1: a schematic representation of a

Rotary feedthrough according to a first

Embodiment in an exploded perspective view;

FIG. 2A: a schematic representation of a

Rotary feedthrough according to a second

Embodiment in perspective

Exploded view;

FIG.2B: an exploded perspective view of one

Support insert for the rotary feedthrough according to

2A; 3 shows a schematic representation of a

Rotary feedthrough according to a third

Embodiment in an exploded perspective view;

FIGS. 4A-4C show variants of the embodiment according to FIG. 3 with differently aligned input and output of the lines;

FIGS.5A-5D: various connectors for modular

configurable variants according to FIG. 3 or FIGS. 4A-4C. In FIG.1-3 is a rotary feedthrough for one or more

Cables, such as cables, hoses or the like. , each generally designated 10. The rotary feedthrough 10 allows a rotational angle limited relative rotation about an axis of rotation A, wherein an uninterrupted passage of at least one line is ensured.

The rotary feedthrough 10 has a housing consisting of two similarly constructed housing parts, namely a first upper housing part 12A, and a second lower

Housing part 12B. Both housing parts 12A, 12B are rotatable about the axis of rotation A relative to each other and axially adjacent to each other at a vertical axis of rotation A.

Interface level.

Each of the two housing parts 12A, 12B respectively defines a substantially hollow cylindrical receiving space 13A, 13B coaxial with the axis of rotation A. In the assembled state, an entire receiving space is created, in which the line course shown in FIG. The lines have a schematically shown course with two around the rotation axis A curved Trumen 14A, 14B, each in the receiving space 13A, 13B of

corresponding housing part 12A, 12B are received. The two strands 14A, 14B are connected to each other by a deflecting bend 15. The deflection arc extends both around the axis of rotation A curved, as well as to a

vertical deflection axis bent substantially U-shaped, said deflection axis is approximately radially to the axis of rotation A in the interface plane. This course is determined by the design of the housing parts 12A, 12B, in particular the shape of the receiving space 13A, 13B.

With relative rotation of the two housing parts 12A, 12B to each other, the position of the movable changed

Deflection arc 15 in the common receiving space, so that the respective length of the strand 14A, 14B changed. The embodiments shown in FIG. 1-3 allow one

Angle of rotation of typically 360 °, maximum 540 °. To specify this desired course, each one has

Housing part a respective cylindrical outer wall 16A, 16B coaxial with the axis of rotation A, the radius of which determines, inter alia, the curvature of the strands 14A, 14B and the deflecting arc 15. In relation to the entire housing has the cylindrical Outside wall 16A, 16B in about half the dimension H of the entire height of the rotary feedthrough 10. This can be in the respective receiving space 13A, 13B of the corresponding

Housing part 12 A, 12 B, the corresponding run 14 A, 14 B are completely absorbed. The outer wall 16A, 16B serves in each case as a radially outer stop or for radial limitation with respect to the course. In FIG. 1-3, each housing part 12A, 12B is thus designed in the manner of a cup-shaped half-shell which is open on one side, an end-side cover 17 being used as the axial termination or stop

is formed integrally with the outer wall 16A, 16B. Furthermore, each housing part has a coaxial to the outer wall

cylindrical inner wall 18A, 18B, wherein outer wall 16A, 16B and inner wall coaxial with the axis of rotation A the

Receiving space 13 A, 13 B give an annular shape (or a hollow cylinder volume).

In the embodiment according to FIG. 1, the purely schematically shown as a hose and only guided line

Line 19 may be guided directly through the housing parts 12A, 12B according to the desired course.

The embodiment according to FIG. 2 differs in two aspects from FIG. On the one hand, an additional corrugated tube 20 is provided by one or more

Protected cables can be added, wherein the corrugated tube 20 in cooperation with the housing parts 12A, 12B specifies the desired uninterrupted line course. On the other hand, the rotary feedthrough 10 according to FIG. 2 comprises an optionally usable additional annular support insert 22, which is rotatably received in the receiving space 13A, 13B. The support insert 22, as best seen in FIG. 2B, has a predominantly annular shape with one of the desired bends of the deflection arc 15

adapted deflection surface 23 and two opposite support surfaces 24A, 24B, which the strands 14A, 14B in the keep desired axial distance to each other. The separately produced support insert 22 also has a cylindrical inner surface, based on which it is rotatably mounted on the inner walls 18A, 18B. The support insert 22 rotates in each case with the rotating housing part 12A, 12B, for example, by means of suitable rotation stops 26. The support insert 22, for example, for guiding particularly resistant to bending

Lines are used.

As an alternative to one-piece housing parts 12A, 12B, the housing in FIG. 3 consists of two multipart parts

Housing parts 12A, 12B. Here is in each of these

Housing parts a frontally or axially and radially outwardly opening recess 28 provided in the form of a cylinder sector. In these recesses 28, depending on the desired application, modular designed connecting pieces 30A, 30B and 31A, 31B used, which make it possible to introduce the guided lines selectable in the tangential direction or in the axial direction in the rotary feedthrough or lead out of this. different

Combination possibilities are shown purely by way of example in FIGS. 4A-4C. The closer shown in FIG.5A-5

Connectors 30A, 30B and 31A, 31B each comprise a passage opening 32 with a strain relief, not shown in detail, for example, a clamping device for the corrugated hose 20 or the line (s) 19. Die

Connectors 30A, 30B and 31A, 31B further comprise disk or cylinder sector shaped wall segments for flush closing of the recess 28 in the respective one

Housing part 12A, 12B and are provided with locking means for the purpose of plug or clip connection fitting to corresponding counterparts on the respective housing part 12A, 12B. The modular equipping with one of several different ones

Connectors 30A, 30B and 31A, 31B are made possible by the axial dimension H of the housing parts 12A, 12B.

LIST OF REFERENCE NUMBERS

A rotation axis

H axial dimension

10 rotary feedthrough

12A, 12B housing parts

13A, 13B recording room

14A, 14B dreams

15 deflection bend

16A, 16B cylindrical outer wall

17 lid

18A, 18B inner wall

19 line (example: hose)

20 corrugated hose

22 support insert

23 deflection surface

24A, 24B support surfaces

25 inner surface

26 rotation stop

28 recess

30A, 30B; 31A, 31B connectors

Claims

claims

Rotary angle limited rotary feedthrough for one or more lines, such as cables, hoses or the like. , full :

a housing with two relative to a rotation axis

rotatable housing parts, wherein the housing defined with respect to the axis of rotation substantially cylindrical receiving space defined for a

continuous course of one or more

Line (s) with two curved around the axis of rotation and a triangular Triangle bend which curves about the axis of rotation and about a vertical deflection axis is bent substantially U-shaped, wherein the housing has a cylindrical outer wall, which the curvature of the strands and of

Deflecting bend around the axis of rotation,

characterized in that each housing part each having a substantial axial portion of

cylindrical outer wall forms to receive one of the two curved strands.

Rotary feedthrough according to claim 1, characterized

characterized in that each housing part in each case forms with respect to the axial height substantially half of the cylindrical outer wall. Rotary feedthrough according to claim 2, characterized

characterized in that each housing part is designed as a half-shell open on one side with a frontal lid.

Rotary feedthrough according to claim 1, 2 or 3, in particular according to claim 3, characterized in that each housing part has a coaxial to the outer wall cylindrical inner wall, said outer wall and

Inner wall define an annular receiving space

Rotary feedthrough according to one of claims 1 to 4, characterized in that at least one housing part has a frontally and radially opening recess for a connecting piece to the input or output of the line (s).

Rotary feedthrough according to one of claims 1 to 5, characterized in that it further comprises a

tubular casing, in particular a

Corrugated hose, to guide one or more

Line (s) comprising the course with the two curved around the axis of rotation and this

pretending connecting bend.

Rotary feedthrough according to one of claims 1 to 6, characterized in that a ring-like support insert is rotatably received in the receiving space with a bend of the deflection bend adapted

Deflection, and two opposite support surfaces, which keep the strands axially spaced.

Rotary feedthrough according to claim 7, characterized

characterized in that the support insert has rotational stops on which this is taken by relative rotation of a housing part.

9. Rotary feedthrough according to one of claims 1 to 8, characterized in that the relative angle of rotation is limited to an angle in the range of 270 ° to 540 °.

10. Rotary feedthrough according to one of claims 1 to 8,

characterized in that one of the dreams

widened over at least one full turn.

11. Apparatus comprising a rotary feedthrough according to one of claims 1 to 10 and at least one electrical cable routed therein without interruption and / or a hydraulic or pneumatic hose guided therein without interruption.

12. Arrangement comprising at least two coaxial

one after the other connected rotary unions according to one of claims 1 to 10 for relative rotation over a rotation angle of more than 540 ° between two

Machine parts.