HK1076543B - Contact arrangement - Google Patents

Description

Contact device

Technical Field

The invention relates to a contact arrangement comprising at least one outer contact piece and at least one inner contact piece, which are guided such that they can move in the longitudinal direction relative to one another, and comprising a rolling contact having contact rollers, which is provided for an electrically conductive connection between the inner contact piece and the outer contact piece.

The invention further relates to a rolling contact for contacting at least one outer contact part with at least one inner contact part, which are guided such that they can move in a displacement direction, wherein the rolling contact has at least one contact roller, which has rolling bodies which bear against the or one outer contact part and against the or one inner contact part and connect them to one another in an electrically conductive manner, and at least one spring element which provides the rolling bodies with the necessary contact pressure, and a rotary shaft.

Background

A contact arrangement of this type and a rolling contact of this type are known from german utility model G9300421.4. The known rolling contact has contact rollers which are arranged between two stationary contact pins on both sides of a contact pin which can be moved in its longitudinal direction, wherein each contact roller with two truncated cone shaped rolling bodies bears on one side against the moving contact pin and on the other side against one of the stationary contact pins. For guiding the movable contact pin in a longitudinally movable manner, the rolling bodies are mounted in a freely rotatable manner on a rotary shaft which has two end flanges at its ends. Furthermore, two preloaded coil springs are provided, which are supported at one end on the end flange and at the other end on the rolling body, as a result of which the rolling body is provided with a contact pressure which is necessary for contacting the rolling body and presses the rolling body against the contact pin. The rolling bodies are made of an electrically conductive material so that the contact pins are connected to each other in an electrically conductive manner. The prior contact device is composed of the contact member and contact rollers provided in pairs.

The previously known contact arrangement has the disadvantage that, in view of the wear occurring and for reasons of reliability, an additional shielding element is absolutely necessary for shielding the contact points between the rolling contact and the contact pin. This increases the manufacturing cost of the conductive member and results in a complicated device structure.

Disclosure of Invention

The object of the invention is therefore to provide a contact arrangement of the type mentioned in the introduction which is simple and compact.

A further problem to be solved by the invention is to provide a rolling contact of the type mentioned in the introduction which can be used in a contact arrangement according to the invention.

Starting from the contact arrangement described in the introduction, the above-mentioned technical problem is solved in that the invention provides a contact arrangement comprising an outer contact piece and an inner contact piece, which are guided movably in the longitudinal direction relative to one another, and comprising a rolling contact with a plurality of contact rollers, which rolling contact is provided for an electrically conductive connection between the inner contact piece and the outer contact piece, characterized in that: the outer contact member has a cavity with a boundary wall concave in cross section, and the inner contact member has a plurality of longitudinal grooves concave in cross section, and the rolling contact is at least partially disposed in a space defined by the cavity and the longitudinal grooves to conduct electric current.

Starting from the rolling contact described in the introduction, the above-mentioned technical problem with rolling contacts is solved in that the spring element is a compression spring arranged between the rolling bodies.

Due to the arrangement of the spring element between the rolling bodies, the rolling bodies are no longer pressed from the outside inward, as in the prior art, but rather from the inside outward. Due to this constructive measure, it is now possible to use a rolling contact in the inner region of an outer contact piece, which is designed with an at least partially concave cross section. The inner contact piece may also project at least partially into the outer contact piece. The spring element thus presses the rolling body on one side against the concave inner wall of the outer contact cavity and on the other side against the outer surface of the inner contact. The contact arrangement is shielded from the outside by the outer contact being an adjustable housing. The invention thus eliminates the need for additional shielding measures for the entire contact arrangement, thereby improving the production, construction and compactness of the entire device.

In a preferred embodiment of the invention, the outer contact is a stationary guide tube in which the inner contact is arranged, which is designed as a longitudinally movably guided contact pin. In this embodiment, the hollow space is thus the interior of a hollow cylindrical and thus concave conduit. In this embodiment, the concave inner wall or boundary wall of the outer contact piece is closed in the form of a ring, as a result of which the encapsulation or shielding of the contact arrangement is further improved.

In a further development of this type, the contact pins have longitudinal grooves on the sides which are located opposite one another, the cross-section of which is concave and which are provided for the mounting of the contact rollers in each case. By means of such an identically concave design of the inner contact piece, the contact surface of the rolling body sweeps over both the contact surface of the outer contact piece and the contact surface of the inner contact piece during a complete revolution of the rolling body. In this embodiment, lateral offset of the contact surfaces, which would otherwise be required, is avoided, so that the contact surfaces are enlarged overall.

In contrast, the outer contact element is a stationary guide tube, in which the inner contact element is guided so as to be longitudinally movable, wherein the inner contact element has a profile shape with a star-shaped cross section, so that a boundary of the partial region in which the contact roller is arranged is formed between the inner contact element and the guide tube. In this expedient development, at least three partial regions are arranged annularly around the longitudinally moving inner contact, as a result of which the guidance of the inner contact is once again improved. But in addition, the contact surface between the rolling contact and the contact piece is increased, so that the heating of the contact device is reduced. In a related development, the longitudinal groove has a curvature in cross section, the radius of curvature of which is equal to the inner radius of the guide tube. By this constructive measure, contact surfaces on the roller which are offset from one another in the cross section are avoided.

In an advantageous further development of the rolling contact according to the invention, the rolling bodies are of a round-cap design, so that such an inner contact piece can be used which is of a star-shaped cross-sectional contour and which delimits at least three sections within the conduit.

In contrast, the rolling bodies can be designed as truncated cones. This expedient development is particularly advantageous if the inner contact piece is designed as a cylindrical contact pin, on both sides of which longitudinal grooves are provided which are circular in cross section and which are provided for the mounting of the rolling contact in each case.

The rolling contact according to the invention can be composed of one contact roller or of a plurality of contact rollers, which are connected to one another by a connecting element, wherein the connecting element does not influence the rolling capacity of the rolling bodies.

Any pressure spring may be used in accordance with the present invention. Coil springs, spiral springs, disc springs, elastomer springs or gas springs are cited as examples only.

Drawings

Other suitable designs and advantages of the invention will appear from the following description of embodiments of the invention with reference to the accompanying drawings. In the drawings:

fig. 1 shows a perspective view of an embodiment of a contact arrangement according to the invention with a rolling contact according to the invention;

fig. 2 shows a cross-sectional view, partly in cross-section, of the contact device and the rolling contact shown in fig. 1;

fig. 3 shows another embodiment of a contact arrangement according to the invention and a rolling contact according to the invention; and

fig. 4 shows a front view, partly in cross-section, of the contact device and the rolling contact shown in fig. 3.

Detailed Description

Fig. 1 shows a perspective view of an embodiment of a contact arrangement 1 according to the invention with a rolling contact 2 according to the invention, wherein a stationary guide tube 3 is shown in a transparent manner, so that the shielded components arranged inside it can also be seen.

The contact device 1 consists of the stationary guide tube 3 designed as an outer contact piece and a contact pin 5, which is guided as an inner contact piece and extends into the cavity 4 of the guide tube 3 so as to be longitudinally movable. Each rolling element 6 of the rolling contact 2, which is composed of a plurality of contact rollers 7, is supported on the guide tube 3 and the contact pin 5. The contact rollers 7 are fixedly connected to one another by a connecting element 8. The connecting element is appropriately fitted over a rotating shaft, which will be described in more detail below, and is connected to it in a rotationally fixed manner (drehfest). In this embodiment, each contact roller 7 has two compression springs 9, which are mounted on the connecting elements 8 and the rolling bodies 6, respectively.

The contact pins 5 have longitudinal grooves 10 for receiving the rolling contacts 2, which grooves are shown as a curve in cross section.

To prevent the rolling contact 2 from sliding off the contact pin 5, a closed stop flange 11 is provided at its end.

Fig. 2 shows a front view in cross section of the contact device 1 and the rolling contact 2 shown in fig. 1. It can be seen from this figure that the rolling bodies 6 of the contact roller 7 are designed as truncated cones and have a non-contacting flattened tip. The longitudinal slot 10 of the contact pin 5 has a curvature. In other words, it forms a circular segment boundary, the radius of which or the radius of curvature of which corresponds to the radius of the outer envelope of the truncated-cone rolling elements 6 and thus essentially to the inner radius of the pipe 3.

Fig. 3 shows a perspective view of a further embodiment of a contact arrangement 1 according to the invention with a rolling contact 2 according to the invention. The inner contact piece 5 shown here is no longer designed as a cylinder, but has a star-shaped profile in cross section and a central through-opening 12, which through-opening 12 is intended for the connection of an extension piece, such as a connecting rod or the like. More closely, the inner contact piece 5 has partitions 13 which are angled at 60 ° to each other. The webs 13 merge into one another in an arcuate manner and form the boundary of the longitudinal groove 10. The longitudinal grooves 10 are therefore curved in cross section, with a radius of curvature that is adapted to the contour of the rolling elements 6 of the contact roller 7, which are designed as circular caps. This triple support and guidance of the inner contact piece 5, which is movable in its longitudinal direction, in the cavity 4 of the guide tube 3 increases the stability of the contact arrangement 1.

Fig. 4 shows the contact device 1 shown in fig. 3 in a front view, partly in cross section. In this illustration, it can be seen in particular that the rolling bodies 6 are loosely fitted on the rigid rotary shaft 14, so that the compression springs, which are composed of the rows of cup springs 9, press the rolling bodies 6 against the inner wall of the guide tube 3 and the inner contact piece 5 which is accommodated in the cavity 4.

It is of course also possible within the scope of the invention to provide the rotary shaft 14 with securing lugs which engage in appropriately arranged cavities, not shown in the drawing, in the rolling bodies 6, so that, on the one hand, the contact rollers 7 are prevented from falling apart when they are removed from the line, and, on the other hand, a sufficiently large displacement of the rolling bodies 6 on the rotary shaft 14 for the generation of pressure is ensured.

In the embodiment shown in fig. 4, the connecting element is eliminated. The row of disc springs constitutes only one pressure spring 9.

List of reference numerals

1 contact device

2 rolling contact

3 catheter

4 cavity

5 inner contact, contact pin

6 rolling element

7 contact roller

8 connecting piece

9 pressure spring

10 longitudinal groove

11 position-limiting flange

12 through hole

13 baffle

14 rotating shaft

Claims (10)

1. A contact arrangement (1) comprising an outer contact piece (3) and an inner contact piece (5) which are guided movably in the longitudinal direction to each other, and comprising a rolling contact (2) with a plurality of contact rollers (7) which is provided for an electrically conductive connection between the inner contact piece (5) and the outer contact piece (3), characterized in that: the outer contact piece (3) has a cavity (4) with a boundary wall which is concave in cross section, while the inner contact piece (5) has longitudinal grooves (10) which are concave in cross section, the rolling contact (2) being arranged at least partially in the space defined by the cavity and the longitudinal grooves for conducting current.

2. The contact device of claim 1, wherein: the outer contact piece (3) is a fixed guide tube (3) in which the inner contact piece, which is designed as a longitudinally movably guided contact pin (5), is arranged.

3. The contact device of claim 2, wherein: the contact pins (5) have the longitudinal grooves (10) on the sides which are opposite to each other.

4. The contact device of claim 1, wherein: the outer contact element is a fixed guide tube (3) in which the inner contact element (5) is guided in a longitudinally movable manner, wherein the longitudinal grooves are arranged such that the cross section of the inner contact element (5) has a star-shaped contour, so that a boundary of the partial region in which the contact roller (7) is arranged is formed between the inner contact element (5) and the guide tube (3).

5. A contact device as set forth in claim 3, wherein: each longitudinal groove (10) has a curvature in cross section with a radius of curvature equal to the inner radius of the duct (3).

6. The contact device of claim 1, wherein: the contact roller (7) has rolling bodies (6) which rest on the outer contact part (3) and on the inner contact part (5) and connect them to one another in an electrically conductive manner, and has at least one spring element which provides the rolling bodies (6) with the necessary contact pressure and a rotary shaft (14).

7. The contact device of claim 6, wherein: the elastic element is a compression spring (9) arranged between the rolling bodies (6).

8. The contact device of claim 7, wherein: the rolling bodies (6) are designed in a circular cap shape.

9. The contact device of claim 7, wherein: the rolling bodies (6) are designed as truncated cones.

10. A contact means as claimed in any preceding claim, wherein: a plurality of contact rollers (7) are provided which are connected to one another by a connecting element (8).