My present invention relates to a device for securing a collar nut or collar screw, hereinafter referred to generally as a screw element having a collar, upon a housing and especially a plastic housing. The invention relates also to a housing assembly as mounted on a support, e.g. an automotive vehicle body, to a method of mounting a housing assembly upon such a support and to an electronic module in which a housing assembly of the aforedescribed type has a printed circuit board between a housing shell and further housing part, referred to interchangeably as first and second housing members.
In the automotive vehicle field it is frequently required to attach various components to the vehicle body by screws. This is the case, for example, for electronic modules which may have a printed circuit board received in a housing and usually provided between a housing shell and another housing part, for example, a housing cover. As a practical matter, a screw can be driven through a hole in one of these housing members and into the vehicle body. However this method is not always possible and in many cases it is necessary either to hold a screw or nut by hand while the other screw element is rotated, e.g. by a socket wrench or the head of a driver which may have a normally flat screwdriver blade shape, a Phillips-head shape, an Allen wrench shape or a Torx head.
A problem in such cases is that the nut or screw can readily be dropped and either a new one must be provided or the dropped screw element must be found before it can be used to mount the housing in place.
It is therefore the principal object of the present invention to provide a housing assembly whereby the above-mentioned drawbacks can be avoided and the mounting of the assembly or an electronic module provided with the housing upon a support can be simplified.
Another object is to provide a method of mounting such an assembly or module upon a support especially an automotive body, which can simplify OEM applications and make the mounting operation less expensive.
These objects are attained, for example, in a housing assembly according to the invention which comprises:
a first housing member and a second housing member juxtaposed with the first housing member to form a module therewith;
a screw element having a collar and engageable through a wall of the first housing member and adapted to be engaged by a mating screw element for mounting the module on a support by rotation of the screw element having the collar; and
a plurality of retainers elastically connected to the wall, bent toward the second housing member and engaging over the collar for retaining the screw element having the collar on the module.
The method of mounting the module can comprise the steps of:
assembling a first housing member, a second housing member juxtaposed with the first housing member, and a printed circuit board between the housing members to form a module, the first housing member having a wall provided with an opening and a plurality of resilient retainers extending into the opening and bent toward the second housing member;
inserting a screw element having a collar into the opening and past the retainers whereby the retainers engage over the collar;
setting the module on a support whereby a mating screw element on the support presses the screw element having the collar away from the printed circuit board and bends the retainers away from the printed circuit board;
inserting a tightening tool into engagement with the screw element having the collar, thereby deflecting the retainers away from the collar; and
tightening the screw element having the collar onto the mating screw element with the tool.
More generally, the method can comprise the steps of:
assembling a first housing member and a second housing member juxtaposed with the first housing member to form a module, the first housing member having a wall provided with an opening and a plurality of resilient retainers extending into the opening and bent toward the second housing member;
inserting a screw element having a collar into the opening and past the retainers whereby the retainers engage over the collar;
setting the module on a support whereby a mating screw element on the support presses the screw element having the collar away from the support and bends the retainers away from support;
inserting a tightening tool into engagement with the screw element having the collar, thereby deflecting the retainers away from the collar; and
tightening the screw element having the collar onto the mating screw element with the tool.
According to the invention, therefore, the retainers are elastically secured to one of the housing members, namely, the housing shell or the other housing part, e.g. by being formed in one piece therewith and are bent toward the interior of the housing, i.e. in the direction of the printed circuit hoard or the housing art or shell to lie against the support surface and are so arranged that they can engage behind the collar of the collar screw or collar nut.
Because of this configuration of the retainers, the screw or nut can be engaged by a tool, e.g. a flat blade driver, a Phillips driver, an Allen driver or a Torx driver, and tightened in or on the mating screw element, thereby pressing and clamping the housing assembly on the support. The screw element provided with the collar is pressed past the retainers which spring over the collar to hold the collar element on the housing assembly. Since the collar screw or collar nut is thereby retained, it can be put in place during fabrication of the module or even just before application of the module to the vehicle body and can thereby become a component of the module so that it will not be lost therefrom.
Advantageously a plurality of such retainers are uniformly distributed around the periphery of the screw or nut. Preferably there are three such retainers. This arrangement is especially desirable for collar nuts since, unlike collar screws, they can slip out of place if fewer retainers are provided. The uniform distribution of the retainers around the screw has been found to be highly advantageous for rapid and reliable attachment of the module to a vehicle body.
To enable the screw or nut to form a conductive contact with the printed circuit board and thus form a ground for the printed circuit board, the recess in the portion of the housing formed with the retainers can have wall portions extending between the retainers which are cylindrically concave, set back from the collar and define a compartment which opens toward the printed circuit board and thus enables the collar nut or collar screw to bear directly upon the printed circuit board. This has the further advantage that the screw head or nut can be located within the outer contour of the housing module and thus be fully recessed therein. The cylindrical wall portion also provides additional guidance for the head of the screw or the nut and facilitates the insertion of the latter.
To ensure an appropriate elasticity of the retainers, cutouts are provided between the retainers and the cylindrical wall portions or segments. The cutouts delimit the wall segment and cantilever the retainers, i.e. the bent fingers, from the wall of the housing between the segments.
The retainers can have an S-shaped corrugated portion between their attachments to the housing wall and the fingers to facilitate deflection of the fingers over the entire length thereof and not only at the junction of each finger with the housing wall. The entire retainer is thus elastically deflectable. This allows, for example, insertion of a socket of a socket wrench between the fingers and deflection of the fingers upon insertion of such socket. The S-shaped corrugated region deposits even significant deformation forces to prevent tearing of the retainers or breaking thereof.
According to a feature of the invention, the housing shell and cover can be connected together via a film hinge. This also facilitates mounting since the housing then becomes one piece and can be more readily handled. The housing may be simply closed by pivoting the two housing parts about the film hinge.
At least at one location along the length of the retainer, each retaining element an have a thickness reduction. The thickness reduction alone or together with the S-shaped corrugated region can serve to improve the spring effectiveness of the retainer. The reduction can be made during fabrication of the retainer or can be made afterward, e.g. by removal of material. Depending upon the degree of reduction, the spring force can be set or adjusted.
The arresting of the collar screw or nut in the housing permits the attachment of the module to the body of an automobile in a very simple manner. After the module is fabricated, one or more collar screws or collar nuts are inserted into the recesses past the retainer fingers. The retainer fingers spring back over the collars to hold the screw elements in place. This can be done on fabrication of the housing or the module. It is also possible to press the screws or nuts into place just prior to mounting.
To mount the module, the module is pressed against the support surface, i.e. the vehicle body, so that the mating pressing element presses the retained nut or screw away and thus lifts the collar nut or head of the collar screw from the printed circuit board. A tool can then be engaged with that head or nut and rotated to tighten the screw into the nut or the nut onto a screw until the printed circuit board is once more engaged and clamped through the housing shell onto the vehicle body. The tool can deflect the retaining fingers outwardly during this step.
The above and other objects, features, and advantages will become more readily apparent from the following description, reference being made to the accompanying drawing in which:
The details of the housing structure and that of the printed circuit board are not important for the purposes of the invention.
What is important is that in the housing part or member 3, having a wall 3d closing the interior 3e of the housing, a plurality of threaded or screw elements 12 are mounted, e.g. in the form of collar nuts which serve to enable the module 1 to be mounted on a support, such as a vehicle wall 13 from which a mating screw element, such as the screw 14 (
The housing part 2 can be provided with an opening 5 through which the screw can project in alinement with the hole 6 in the printed circuit board with a passage 11 in the wall 3d through which the collar nut 12 can be inserted to rest against the printed circuit board 4 directly (
The collar nut is held in place by a plurality (at least three) of angularly equispaced resilient retaining fingers 8 which, as can be seen from
The fingers 8 form terminal elements of retainers 7 which are separated from the remainder of the wall 3d by slits 12b but are connected to the wall by rear portions 9 which are bent and molded to have an S shape (compare
Between the retainers, the wall 3d is set back to form the opening 11.
The housing parts 2 and 3 can, in addition, be interconnected by a film hinge as represented at 3f in
In the opening in the housing wall 3d formed by the concave wall segments 11, a screw element formed with a collar, can be inserted through the wall 3d to lie against the printed circuit board 4 with its internally threaded portion 12b in alignment with a hole 6 in the printed circuit board and a passage 5 in the bottom wall of the housing shell 2 (see
Number | Date | Country | Kind |
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10331011.8 | Jul 2003 | DE | national |
10357095.0 | Dec 2003 | DE | national |