The present application claims priority under 35 U.S.C. §119 to German Patent Application No. 20 2007 005 029.1, filed on Apr. 4, 2007, the entire disclosure of which is incorporated herein by reference.
The invention relates to an electrical plug connector part with a locking nut that is rotatable relative to the plug body and can be screwed onto an associated matching plug part and that is secured against unintentional rotation relative to the plug body by matched latch elements, wherein first latch elements are rigid and are molded onto the locking nut, and corresponding second latch elements are mounted rotation-proof and with spring action on the plug body.
Plug connectors with a locking nut for screwing onto a matching plug part, in particular for preventing unintentional disconnection of the plug connection, are known in a wide variety of embodiments. DE 197 21 506 C2 and DE 102 24 000 B4 are cited as examples.
DE 197 21 506 C2 discusses an electrical plug connector part with a clamping nut that is rotatable relative to the plug body and with a rotation lock for the clamping nut that is formed by a locking ring gear and a latch element. The locking ring gear is provided on the inner circumference of the clamping nut, and the latch element on the outer circumference of the plug body. The latch element is mounted rotation-proof on the plug body and has one or several latching teeth pointing radially outward. The at least one latching tooth engages the locking ring gear, and between the plug body and the clamping nut, a sleeve is provided that has an opening for the latching tooth.
DE 102 24 000 B4 teaches an electrical plug connector part with a locking nut that is rotatable relative to a contact carrier and is protected against unintentional turning by a rotation lock, with the rotation lock having a ring gear located on the locking nut and a latch ring fixed on the contact carrier. On the latch ring, at least two integrated spring elements are provided that carry a latch projection that works together with the ring gear. In terms of the circumference, the latch projections are spaced at an angle of less than 180°.
In known plug connector parts, the locking nut configured as a clamping nut is frequently made of metal in order to connect the shield of a shielded cable in an electrically conducting way with the matching plug part. Usually, the contact carrier and/or the plug body are made of a synthetic material whose spring characteristics are insufficient for creating a latch element with spring-back action. Also, equipping a locking nut with a locking gear ring on its inner circumference makes it costly to manufacture, especially in the case of a metallic clamping nut, thereby raising the costs which is a disadvantage.
The invention addresses the problem of proposing an electrical plug connector part with a rotation lock for the locking nut of the type referred to above, where the rotation lock is easy to manufacture and install and ensures a permanent, safe and cost-effective vibration-proof connection of the plug body and the locking nut.
According to the invention, the locking nut and the plug body have an equal number N of first and second latch elements that are spaced apart from each other and are arranged in sequence in a circumferential direction. The first latch elements are located on an inner circumference of the locking nut, and the second latch elements are located on an outer circumference of the plug body. The first latch elements of the locking nut are spaced differently than the second latch elements of the plug body.
The N first and the second latch elements that have complementary shapes do not follow each other directly. Specifically, the first latch elements on the locking nut do not form a locking ring gear. The maximum number N of the first and second latch elements depends essentially on the size of the plug connector part. Depending on the number N of the latch elements, more or fewer latching positions may be determined that are preferably spaced at the same angle in a circumferential direction. It is expedient to provide at least three latch elements each on the locking nut and on the plug body in order to provide a sufficient number of latch positions.
Advantageously, the first and the second latch elements are distributed over their respective circumferential surfaces in such a way that, depending on the position of the locking nut relative to the plug body, no more than one first and one second latch element face each other.
The latch positions are those positions in which one first and one second latch element face each other. In the latch position, the first and the second latch elements interact. They are then mutually engaged and secure the locking nut against unintentional turning in relation to the plug body. In order to disengage the rotation lock, a torque that is dependent on the spring characteristics of the latch elements needs to act on the locking nut. Between the latch positions, other positions are possible in which the first and second latch elements are staggered in relation to each other, with the springy latch elements being pressed against the inner circumference of the locking nut by the plug body. Their prevention of a rotation of the clamping nut is less than positive.
Preferably, the N latch elements of the locking nut and of the plug body determine (N×N) latch positions of the plug connector that have the same angular distance of [360°/(N×N)] from each other. For example, three latch elements each on the locking nut and on the plug body determine 9 latch positions, and four latch elements each determine 16 latch positions. Here, the latch positions are equally distributed over the circumference of the locking nut and the plug body, respectively, with the nine latch positions staggered at an angle of 40°, and the 16 latch positions staggered at an angle of 22.5°. It can be seen that the number of latch positions grows exponentially with the number of the latch elements that are provided.
In an advantageous embodiment, the first or the second latch elements are arranged with even circumferential spacing, i.e. the latch elements with even spacing may be provided either on the locking nut or on the plug body. Except for a larger distance, the other latch elements associated with the evenly spaced latch elements are spaced at even but smaller distances from each other. The result is that when the locking nut is rotated, the N latch elements of the locking nut engage, in a staggered sequence, the latch elements of the plug body one after the other.
In the electrical plug connector according to the invention, the angular distance of the evenly distributed latch elements in relation to the virtual center axis of the circumferential surfaces of the locking nut and of the plug body, respectively, is (360°/N) and the smaller even angular distance of the other latch elements is [(360°/N)×(1−1/N)]. When four latch elements each are provided, for example, the angular distance for the evenly distributed latch elements is 90°, and for the complementary latch elements three times the smaller distance of 67.5° and once a larger distance of 157.5°. Due to the special arrangement of the latch elements, 16 latch positions are defined that enclose an angle of 22.5° between each other.
In one embodiment of the electrical plug connector according to the invention, the first latch elements on the locking nut are latch recesses and the second latch elements on the plug body are latch projections. Preferably, the latch recesses and the latch projections mirror each other, with the latch projections being movable in a radial direction relative to the plug body. The second latch elements of the plug body are preferably provided on a latch ring that is mounted rotation-proof on the plug body. In the interest of good spring characteristics, the latch ring is preferably made of metal, specifically spring steel or spring bronze.
To the accomplishment of the foregoing and related ends, the invention, then, comprises the features hereinafter fully described and particularly pointed out in the claims. The following description and the annexed drawings set forth in detail certain illustrative embodiments of the invention. These embodiments are indicative, however, of but a few of the various ways in which the principles of the invention may be employed. Other objects, advantages and novel features of the invention will become apparent from the following detailed description of the invention when considered in conjunction with the drawings.
On the inner circumferential surface 10 of the locking nut 3, latch recesses 18 are provided as first latch elements, and, as second latch elements, corresponding latch projections 17 are provided on the spring arms 9; in certain positions of the locking nut 3 relative to the plug body 2, the first and second latch elements are able to engage each other. The latch ring 8 shown in
In the interest of a clearer view,
Although the invention has been shown and described with respect to certain preferred embodiments, it is obvious that equivalents and modifications will occur to others skilled in the art upon the reading and understanding of the specification. The present invention includes all such equivalents and modifications, and is limited only by the scope of the following claims.
Number | Date | Country | Kind |
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20 2007 005 029.1 | Apr 2007 | DE | national |