DE29601407U1 - Coaxial connector - Google Patents

Description

PATENT ATTORNEYS

DiPL.-ING. R. LEMCKE
DR.-ING. HJ BROMMER
DIPL.-ING. F. PETERSEN

BISMARCKSTRASSE 16

76133 KARLSRUHE

TELEPHONE (OT 21) 912800

FAX (07 21) 21105

10 January 1996 16 516 (Bl/sp)

Description

The invention relates to a coaxial plug for plugging onto a socket, consisting of a pin-shaped inner pole and an outer pole surrounding it in a ring, which is designed to be elastically flexible due to a slot arrangement and thus serves to radially brace the plug and socket.

Such plugs are used in particular in the audio sector for the transmission of low-frequency signals. When the coaxial plug is plugged into the socket, the pin-shaped inner pole of the plug is inserted into the correspondingly shaped, hollow-cylindrical inner pole of the socket, while the ring-shaped outer pole of the plug is pushed over the correspondingly shaped cylindrical outer pole of the socket.

In order to fix the axial position of the plug on the socket and thus to maintain the plug connection, it is known to provide the cylindrical inner pole over a large part of its axial extension with a slot penetrating the entire thickness of the inner pole and to slightly widen the two resulting pole halves, whereby they press against the hollow cylinder wall of the socket due to their pre-tension

and thus create a friction fit along its surface with the hollow cylinder. On the other hand, the outer pole can also be slotted and consist of pressing tongues lying next to each other, which, due to the greater length of the bending zones of these pressing tongues compared to those of the slotted inner pole, enables the plug to withstand greater stress and thus a better and more reliable fit.

However, it has been shown that these individual elastic pressure tongues are too flexible, particularly for one-sided and uneven loads, such as those that occur when the socket and plug are inserted into each other at an angle, which leads to plastic deformation of the overstressed bending zones of individual pressure tongues and thus in turn to a deterioration of the plug seat.

Based on such a known coaxial connector, the object of the present invention is to further improve this coaxial connector and to increase its load-bearing capacity with regard to vibrations and other stresses so that it is able to absorb even asymmetrical loads and forces safely and elastically.

This object is achieved according to the invention in that the outer pole has an annular spring element on its outside.

This has the advantage that not only the bending zones at the slot ends of the pressure tongues

ne are responsible for absorbing loads and the elasticity of the outer pole, but they are also supported by the spring element arranged along at least part of the circumference of the outer pole. Due to such an elastic arrangement of the spring ring on the pressure tongues, it is ensured that the forces acting on the outer pole, possibly even on one side, are passed on to the spring ring and distributed there over the entire circumference. This means that much greater forces can be absorbed than with the conventional design and plastic deformations in the bending zones can be reliably avoided without this leading to a reduction in the elasticity of the pressure tongues.

In addition, the use of the separate spring ring has the advantage that even in the event of excessive stress on the plug, which would lead to a plastic expansion of the spring ring and consequently to a deterioration of the plug seat, the spring ring can be easily replaced without the entire plug having to be replaced. If the use of the spring ring already means that the outer pole can absorb greater forces without damage, this advantage is increased even further by the replaceability of the spring ring, since excessive stresses that lead to a plastic deformation of the spring ring can still be absorbed without affecting the quality of the future plug seat.

In this context, it is recommended that the spring ring is pre-tensioned against the outer pole,

i.e. it is in constant contact with the outer pole even when it is not under load. This ensures that the outer pole does not have to absorb forces greater than the spring ring at any time if the bending stiffness of the outer pole and the spring ring is suitable, thus largely eliminating the risk of plastic deformation of the outer pole. In addition, this means that the spring ring cannot be accidentally stripped off and lost when the outer pole is not under load - i.e. when the socket is not inserted.

It is particularly advantageous if the outer pole has a circumferential recess on its outside, which serves to accommodate and fix the spring ring in position, whereby the recess is suitably designed in the form of a groove. In this case, it is expedient if the recess is arranged in the area of greater flexibility of the outer pole, i.e. in the axial direction near the plug end or at least the middle of the outer pole, because this allows the spring ring to perform its function of absorbing forces exerted on the outer pole most effectively.

The elastic flexibility of the outer pole is increased even further if the pressure tongues of the outer pole in the foot area have a circumferential cross-sectional reduction on their outside to reduce the bending stiffness which is also expediently designed in the form of a groove. This reduction in the bending stiffness is only possible because the spring ring reduces the bending of each pressure tongue on the

elastic deformation range and prevents plastic deformation.

The clamping of the respective inner poles of the plug and socket can be improved by providing the inner pole with a slot that penetrates the entire thickness of the inner pole over a large part of its axial extension and by roughening at least part of its circumference. This roughening is advantageously achieved by providing the inner pole with a knurled surface along its circumference. This improves the friction fit and thus also the contact between the two inner poles.

In summary, the advantage of the present invention is that the outer pole itself can be made even more flexible, whereby the spring element provided according to the invention elastically absorbs the forces acting on the outer pole and can be easily replaced in the extreme case of plastic overload.

Further features and advantages of the present invention will become apparent from the following description of an embodiment based on the drawing; in this case:

Figure 1 shows the plug according to the invention in

perspective side view;

Figure 2 shows the plug from Figure 1 in disassembled condition;

Figure 3 is a plan view of the plug end; Figure 4 is an axial section through the plug; Figure 5 is the spring element according to the invention.

The coaxial connector 1 shown in Figure 1 consists of an approximately cylindrical base body 3, a pin-shaped inner pole 13 and a ring-shaped outer pole 11, which in turn has a cylindrical to slightly conical outer surface and a cylindrical inner surface, via which it rests on the outer pole of a corresponding socket, which is inserted into the recess 16 delimited by the outer pole. Axial slots are provided in the outer pole 11, which divide the outer pole into several pressing tongues 18 lying next to one another. A groove 20 is provided in the base area of the pressing tongues, which reduces the wall cover of the pressing tongues 18 in such a way that each pressing tongue forms an elastically flexible spring element, whereby the outer pole 11 is always in contact with the outer pole of the socket with its inner side when plugged onto a socket, which ensures the transmission of signals.

The pressure tongues also have, approximately in the middle of their axial extension, another circumferential groove 19 on their outside, into which an elastically flexible spring element 17 in the form of a ring spring is inserted. This spring element serves to absorb the forces exerted on the outer pole when plugging it into the socket or when other loads are applied, and thus to reduce the bending of the pressure tongues so that their deformations are kept in the elastic range.

Figure 2 shows the complete plug set 10 in a disassembled state, which makes it clear how a signal line 4 is attached to the plug 1: This signal line 4 contains two conductor wires, one of which is attached to the inner pole 13 via a connection point 13' and the other is connected to the outer pole 11 by being soldered into an opening 15 of a clamping shoe 12 that is in contact with the outer pole 11, as can also be seen in Figure 4. After the conductor wires have been electrically connected to the respective poles, the signal line 4 is also attached to the plug via the clamping shoe 12 and the sleeve-shaped base body is then screwed onto a thread 14 provided on the outer pole 11.

Figure 3 shows a top view of the plug end. The axial section in Figure 4 once again shows the design of the grooves 19 and 20 of the spring ring 17. It can also be seen from this that the inner pole 13 is knurled in the area near the plug end in order to increase the surface roughness. Furthermore, the inner pole 13 is spaced from the outer pole 11 by means of an insulator 21, which prevents mutual contact.

Finally, Figure 5 shows the spring ring 17, the inner surface of which is cylindrical in order to provide as flat a contact surface as possible for the pressure tongues 18. Furthermore, a slot 21 can be seen here, which interrupts the spring ring 17, whereby it can be expanded while overcoming its bending stiffness.

Claims (7)

PATENT ATTORNEYS ·"· * *··* ··· DIPL.-ING. R. LEMCKE DR.-ING. H. J. BROMMER DiPL.-ING. F. PETERSEN BISMARCKSTRASSE 16 76133 KARLSRUHE TELEPHONE (0721) 912800 FAX (0721) 21105 10 January 1996 16 516 (Bl/sp) Protection claims 1. Coaxial plug for plugging into a socket, consisting of a pin-shaped inner pole and an outer pole surrounding it in a ring, which is designed to be elastically flexible due to a protective arrangement and thus serves to radially brace the plug and socket, characterized in that the outer pole (11) has an annular spring element (17) on its outer side. 2. Coaxial connector according to claim 1, characterized in that the annular spring element (17) is prestressed relative to the outer pole (11). 3. Coaxial connector according to claim 1, characterized in that the outer pole (11) has a circumferential recess (19) on its outside, which serves to accommodate and fix the position of the spring element (17). 4. Coaxial connector according to claim 3, characterized in that the recess (19) is designed in the form of a groove. • * At ■ C · t··· · 5. Coaxial connector according to claim 1, characterized in that the outer pole (11) has approximately axially extending slots along its circumference, penetrating the outer pole wall, so that the protective arrangement of the annular outer pole is formed by pressing tongues (18) lying next to one another. 6. Coaxial connector according to claim 5, characterized in that the pressing tongues (18) of the outer pole (11) have a cross-sectional reduction (20) in the foot area on their outside to reduce the bending stiffness. 7. Coaxial connector according to claim 1, characterized in that the inner pole (13) is provided over a large part of its axial extension with a slot penetrating the entire inner pole thickness and is roughened at least in partial areas of its circumference.