COAXIAL CONNECTION SYSTEM FOR RF SIGNALS WITH HIGH RF PERFORMANCE LEVELS

Abstract

The invention relates to a coaxial connection system in which solid insulating structures are used and it is provided a lengthening of the guide portion of the connectors, while ensuring an axial immobilization of the ground contacts independently of the locking device that mechanically locks the plug to the jack when they are in mutual connection configuration.

Claims

1. A coaxial connection system, intended to transmit radio frequency RF signals, of longitudinal axis X, comprising a first system element forming a plug and a second system element forming a jack, the plug and the jack each comprising: a central contact, a peripheral contact, arranged on the periphery of the central contact, forming a ground contact, a solid insulating structure interposed between the central contact and the ground contact, in which the jack comprises a body having a cylindrical inner surface forming a guiding portion, wherein one of the ground contact is elastic and comprises a slotted sleeve, whereas the other cooperating ground contact is rigid, the elastic one bearing radially against the inner surface of the rigid one in connection configuration between the plug and the jack; and wherein the outer surface of the ground contact of the plug is forming a guiding portion which is mechanically guided against the guiding portion of the body of the jack, during the connection, said guiding portion of the ground contact of the plug having a diameter D and a length L along the axis X, defining a ratio L/D which is superior or equal to 0.5.

2. A coaxial connection system according to claim 1, wherein the difference (E), namely the radial clearance, between the diameter of the guiding portion of the body and the diameter D of the guiding portion of the ground contact of the plug is sized such that the ratio E/L is inferior to 0.05.

3. A coaxial connection system according to claim 1, wherein the difference (E), namely the radial clearance, between the diameter of the guiding portion of the body and the diameter D of the guiding portion of the ground contact of the plug is sized such the tilting angle (α) between the jack and the plug, in their mutual connection configuration, inferior to 3°.

4. A coaxial connection system according to claim 3, wherein the value of the tilting angle (α) between the jack and the plug keeps below 7°, when the slotted ground contact just connects the inner surface of the rigid one during the mating or, when the slotted ground contact disconnects the inner surface of the rigid one during the unmating.

5. A coaxial connection system according to claim 1, wherein the solid insulating structure presents holes or one or more hollowness.

6. A coaxial connection system according to claim 1, comprising a locking device suitable for mechanically locking the plug to the jack when they are in mutual connection configuration

7. A coaxial connection system according to claim 6, wherein said locking device is of screw/nut type and consisting of a nut mounted free in rotation around the plug and a screw, the threads of which are formed on the periphery of the body of the jack.

8. A coaxial connection system according to claim 6, wherein said locking device is of snap-lock type and comprising a coupling ring mounted around the plug, the coupling ring having at least a latching hook which are adapted to snap into a groove formed at the periphery of the body of the jack in the connection configuration, the snapping being carried out during the connection.

9. A coaxial connection system according to claim 6, wherein the snap-lock device comprises a unlocking nut which is mounted free in translation around the plug, the unlocking nut having a surface protruding to the inside and adapted to disengage the hooks from the peripheral groove of the body of the jack, upon movement of the nut in the opposite direction of the connection direction.

Description

DETAILED DESCRIPTION

[0041] Other advantages and features of the invention will become more apparent on reading the detailed description of exemplary implementations of the invention, given as illustrative and non-limiting examples with reference to the following figures in which:

[0042] FIG. 1 is a longitudinal cross-sectional view of a coaxial power and low passive intermodulation connection system series 7/16, according to the prior art, the plug and the jack being in mutual connection and locking configuration;

[0043] FIG. 2 is a longitudinal cross-sectional view of a coaxial connection system according to the prior art, marketed under the series 4.3-10, the plug and the jack being in mutual connection and locking configuration;

[0044] FIG. 2A shows the mating risk induced in the system in FIG. 2;

[0045] FIG. 3 is in longitudinal cross section a coaxial connection system according to the invention, the plug and the jack being in a ready position to be connected;

[0046] FIG. 3A shows the position of the beginning of the mating of the plug into the jack of the coaxial connection system of the FIG. 3;

[0047] FIG. 3B shows the mutual connection of the plug into the jack of the coaxial connection system of the FIG. 3;

[0048] FIG. 3C shows the maximum allowable tilting angle during the mating and unmating phases of the plug into the jack of the coaxial connection system of the FIG. 3;

[0049] FIG. 4 is a longitudinal cross section view of a plug of a coaxial connection system according to the invention, equipped with a nut of a locking device of screw/nut type;

[0050] FIG. 4A is a longitudinal cross-sectional view of a coaxial connection system according to the invention using the plug according to FIG. 4, the plug and the jack being in mutual connection and locking configuration;

[0051] FIG. 5 is a longitudinal cross section view of a plug of a coaxial connection system according to the invention, equipped with a coupling nut and a coupling ring of a locking device of snap-lock type;

[0052] FIG. 5A is a longitudinal cross-sectional view of a coaxial connection system according to the invention using the plug according to FIG. 5, the plug and the jack being in mutual connection and locking configuration;

[0053] FIGS. 1 to 2A relate to different examples of coaxial connection systems according to the prior art.

[0054] These FIGS. 1 to 2A have already been commented on in the preamble and will not therefore be commented on further herein below.

[0055] In the interests of clarity, the same references designating the same elements of a connection system according to the prior art and of a connection system according to the invention are used for all the FIGS. 1 to 5A.

[0056] Hereinafter, the invention is described with reference to any type of RF line.

[0057] In the coaxial connection system according to the invention 1, each of the plug 2 and the jack 3 comprises a solid insulating structure 23, 33 interposed between the central contact 20, 30 and the ground contact 21, 31. Thus, compared to a connector marked under series 4.3-10, as shown on FIG. 2, the jack 3 includes a solid insulating structure 33 between the central contact 30 and the ground contact 31. This solid insulating structure 33 protects physically the female center contact 30 and the slotted elastic ground contact 31 during the mating (connection). Besides, it avoids the risk of accidental damages due to the intrusion of external objects.

[0058] As shown on FIGS. 3, 3A, 3B, 4A and 5A, the jack 3 according to the invention comprises a body 32 having a cylindrical inner surface forming a guiding portion 320.

[0059] In the coaxial connection system 1 according to the invention, the free end of the body 32 is in longitudinal mechanical abutment against a part 25 of the plug 2 when they are in mutual connection configuration, such that it is provided a minimum axial gap (J) between ground contacts along the axis X (FIGS. 3B, 4A, 5A). In the shown embodiments, the part 25 of the plug which forms an abutment is a shoulder provided at the periphery of the plug 2. In the snap-lock configuration, the final axial gap (J) when fully mated is provided through the abutment of the hook 41 in the groove 321 and the free end of the body 32 against the O-ring seal 6.

[0060] According to the invention and shown on FIGS. 3 to 5A, the sizing has be made such that the guiding portion 210 has a diameter D and a length L along the axis X, defining a ratio L/D which is superior or equal to 0.5. For example in the shown embodiment, the ratio L/D is equal to 0.55. By comparison, this ratio L/D is of the order of 0.3 only in the 4.3-10 series.

[0061] Compared to all the coaxial connecting systems of the prior art, the length of the guiding, which is active from the beginning of the connection is increased in a substantive manner.

[0062] The inventors have analysed that such a big length L for the guiding portion with a high ratio L/D, combined with a low radial gap (radial clearance) E between the diameter of the guiding portion 320 of the body 32 and the diameter D of the guiding portion 210 of the plug 2 leads to a possible transverse tilt, which is low and a higher stability, namely a better coaxiality of the connection. Accordingly, the passive intermodulation is lower compared to the coaxial connection systems of the prior art.

[0063] Preferably, the sizing is such that the tilting angle α between the jack 3 and the plug 2, in their mutual connection configuration is inferior to 3°, preferably inferior to 1.5°. Alternatively and/or in combination with, the sizing is such that the ratio E/L is inferior to 0.05, preferably inferior to 0.03.

[0064] Moreover, in the coaxial connection system 1 according to the invention, the electrical ground path is made between the part 31, more specifically between the bump at the free end of the part, and the internal surface of the complementary body 21 (FIG. 3B). On the other hand, the mechanical guiding is done by the guiding portions 210 and 320.

[0065] Due to the recess of the ground contact 31 to the portion 320, the mechanical guiding provides a better alignment before the connection of the electrical contact. (FIG. 3C). The value of the tilting angle α between the jack and the plug keeps below 7°, when the slotted ground contact 31 just connects the inner surface of the rigid one 21 during the mating or, when the slotted ground contact 31 disconnects the inner surface of the rigid one 21 during the unmating. Therefore, the electrical ground contact is protected from repetitive mating/unmating operations and consequently, the intermodulation is lower and more stable.

[0066] FIGS. 4 to 4A show a first variant of a locking device 4 suitable for mechanically locking the plug 2 to the jack 3 when they are in mutual connection configuration. In this illustrated variant, the locking device 4 is of screw/nut type. After the mutual connection has been achieved, a nut 24 which mounted free in rotation around the plug 2 is screwed onto threads 34 formed on the periphery of the body 32 of the jack 3. The locking configuration is thus achieved.

[0067] FIGS. 5 to 5A show a second variant of a locking device 4 which is here of a snap-lock type. At the end of the mutual connection, the peripheral portion of the body 32 moves apart radially some latching hooks 41 of a coupling ring 40 mounted around the plug 2 and then, the hooks 41 are snapped into a groove 321 of the body 32.

[0068] To unlock the plug 2 from the jack 3, the device 4 comprises an unlocking nut 42 which is mounted free in translation around the plug 2, the unlocking nut having a surface 43 protruding to the inside. Thus, upon movement of the nut 42 in the opposite direction of the connection direction, the surface 43 will disengage the hooks 41 from the peripheral groove 321 of the body 32 of the jack 3.

[0069] The advantages of a coaxial connection system 1 according to the invention, which has just been described, are numerous compared to a coaxial connection system according to the prior art, such as the one marketed under the designation series 7/16 or under the designation 4.3-10 or such as disclosed in the WO2014/026383 patent application: [0070] a sure mechanical protection of both elastic outer contacts and center contacts; [0071] high RF signal transmission performance levels maintained, even increased, with in particular a low and stable over time of passive and dynamic intermodulation levels; [0072] miniaturization of the connection compared to low passive intermodulation connectors of the prior art.

[0073] Other variants and enhancements can be provided without in any way departing from the framework of the invention.

[0074] The expression “comprising a” should be understood to be synonymous with “comprising at least one”, unless otherwise specified.