Patent Application
20100092239
This application claims priority of European Patent Office Application No. 08017922.9 EP filed Oct. 13, 2008, which is incorporated by reference herein in its entirety.
The invention relates to a fixing element comprising a bolt with a first region having a first cross-section and a second region having a second cross-section, a clamping wing with a first bearing surface, with the clamping wing being arranged in the second region, a transition between the first and the second region, which is embodied at least partially as a second bearing surface, with the first and the second bearing surface being arranged opposite one another so that a first material part and a second material part can be mounted between the first bearing surface and the second bearing surface by executing a rotary motion.
The invention also relates to an apparatus in a first material part for accommodating a fixing element including a cylindrical socket with an insertion opening and an outlet opening, with it being possible to insert the fixing element into the insertion opening and said fixing element partially protruding beyond the outlet opening in order to include a second material part.
For the assembly of electronics systems for instance, according to the application, a more or less large number of modules are suspended adjacent to one another on a profile rail fastened to a switching cabinet wall for instance. In such cases an upper edge of the module is inserted first and the lower edge engages with the profile rail by means of a pivoting movement and the module is thus brought into its final position. When positioning the modules, said modules are preferably in contact with one another by way of a rear wall bus and/or by way of connecting terminals. A secure fixing possibility is needed in order to guarantee all contacts, even under industrial conditions for instance, such as particular vibrations, shock, dust, heat, cold etc. Hooking a module over a profile rail by means of a snap-on hook is disadvantageous in that the snap-on hook, in order to guarantee its ability to snap on behind the rail, has to have a play between a detent and the profile rail. If this play does not exist, the snap-on mechanism does not work. This play nevertheless results in an inadequate contact force prevailing between the module and the profile rail in the case of a correctly dimensioned snap-on hook in the locked state, said contact force not being well-suited for use under industrial conditions.
A solution of the previously cited module which can be engaged in a profile rail in which a screw connection is used rather than the snap-on hook, is also disadvantageous since a number of complete turns are needed in order to tighten the screw and the assembler requires more time for the assembly.
EP 0 943 824 B1 discloses a mechanical connecting element as a quick release fastener with the features of the fixing element cited in the introduction. This connecting element is disadvantageous in that a travel resulting from the rotary motion is not sufficient to generate a required contact pressure.
An object of the invention is to provide a fixing element which generates greater travel in the case of a rotary motion of the fixing element and thus a better tolerance compensation.
The object is achieved in that the second bearing surface has at least a first sliding part and a second sliding part, with, starting from an insertion position, a tension force increasing in the axial direction until a locking position is reached as a result of the rotary motion. Since the clamping wing with a first bearing surface in accordance with the prior art with relatively small surfaces on the clamping wing only allows a small travel, it is advantageous for the fixing element to have additional sliding parts on its second bearing surface, with the sliding parts being embodied as ramps extending around the bolts. As the bearing surface of the fixing element is generally dimensioned to be larger than the clamping wing, a greater travel and thus a considerably greater clamp travel can be generated by means of an embodiment of the sliding parts during a rotary motion of the fixing element. The second bearing surface, which was previously a flat, planar surface, and/or as described in EP 0 943 824 B1, which is provided on one side with securing edges shaped like a blade, is thus embodied with additional sliding parts so as to increase the contact path in accordance with the invention.
In one advantageous embodiment, the clamping wing has a first wing part with a first bevel and a second wing part with a second bevel, with the first and the second bevel forming the first bearing surface. During the rotary motion, the bevels of the clamping wing become wedged in a cavity of the second material part which is provided herefor and, as a result of their bevels, likewise provide for a proportionate travel and/or for the generation of a proportionate tension force. If the fixing element is used for instance as a quick release fastener for a module with an apparatus provided correspondingly herefor, it is also advantageous for the clamping wing to be two parts, in other words a first wing part and a second wing part, since this “double wing” prevents a lateral displacement of the module during the locking process as a result of the one-sided friction of the clamping wing on a profile rail wall for instance. This is advantageous in that a “play-free” position results in the assembled state, i.e. the tolerances between the bearing surfaces are minimized.
It is also advantageous for the clamping wing to be configured so as to penetrate into an opening in the second material part. The clamping wing is configured here such that it can penetrate through an opening, for instance in the profile rails already mentioned and is twisted into a position whereby the clamping wing is prevented from slipping out.
In a further optimized configuration, the first sliding part and/or the second sliding part is configured for the positive connection to a first opposing surface and/or to a second opposing surface of the second material part. An angle of the sliding parts is selected in the case of a material pairing used in each instance such that a self-locking occurs. In other words, the locking device does not open by itself, since the frictional forces on the pressed surfaces are greater than the resulting forces, which would move the locking device to open as a result of the clamping.
Since fixing elements of this type could possibly fall out of their apparatuses during assembly, by way of a head for instance, it is advantageous for the first region to be configured with a groove for accommodating a latching lug. This latching lug, which engages in the groove, nevertheless allows for rotation of the fixing element, but prevents the fixing element from falling out of the component to be fixed in each instance. The fixing element is thus captive with regard to the respective material or component.
A head region of the first region is preferably configured to accommodate a tool for exerting the rotary motion. A hexagon or a slot for accommodating a tool is arranged on the head region for instance.
As the rotary motion of such a fixing element is generally restricted to a quarter rotation, it is advantageous for a stop for restricting the rotary motion to be arranged at the transition point. Rotation beyond a maximum torque to be generated is thus prevented.
The apparatus cited in the introduction likewise achieves the object cited in the introduction since the apparatus and the fixing element relate to a common inventive idea.
The object is thus achieved with the apparatus in that at least one first opposing surface and/or a second opposing surface are arranged within the socket as a opposing bearing for the positive connection of a first sliding part and/or a second sliding part, with the opposing surfaces having a ramp-shaped characteristic. The combination of ramp-shaped sliding parts on the fixing element and ramp-shaped opposing surfaces in the apparatus enable travel to be maximized despite the small design of the fixing element by using an amplifying travel if a ramp-shaped sliding part rests on a ramp-shaped opposing surface and in the case of a rotary motion.
To realize the already mentioned captive facility, it is advantageous for a flexible bar to be formed in a socket wall by means of two longitudinal sections in the apparatus which is in parallel with a symmetry axis of the socket and for the bar to have a latching lug. This latching lug can engage in the previously mentioned groove of the fixing element and can provide for the fixing element to be held captive by the apparatus.
One particularly advantageous embodiment is if the socket is arranged in or on a housing of an automation component in order to fix this automation component to a profile rail.
Further advantageous embodiments and possible models are explained with reference to the drawing, in which:
According to
In
The first bevel 11a and the second bevel 11b also generate an additional travel as a result of the anchoring in the profile rail 28 shown in
In accordance with
As viewed based on an insertion opening 22, the bar 24 has a latching lug 13 at the start. This latching lug 13 is embodied so as to engage in the groove 12 of the fixing element 1 and thus renders the fixing element 1, in the inserted state, captive in respect of the socket 21. If the fixing element 1 is inserted in the socket 21 and is positioned in an insertion position, the first sliding part 8a and the second sliding part 8b are placed on a first opposing surface 9a and a second opposing surface 9b by means of a rotary motion, said opposing surfaces being arranged inside the socket 21 on the socket wall 9a. The first opposing surface 9a and/or the second opposing surface 9b form a opposing bearing for the first sliding part 9a and/or the second sliding part 9b for the positive connection of the first and second sliding part 8a, 8b. The opposing surfaces 9a, 9b here are in the shape of a ramp.
Starting from the insertion position, the clamping wing 4 with its first bevel 11a and its second bevel 11b protrudes into a profile rail groove of the profile rail 28. With the said rotation in the clockwise direction, the clamping wing 4 thus also turns so that it comes to rest in its end position with is first bevel 11a on a second holding surface 28b and with its second bevel 11b on a first holding surface 28 inside the profile rail groove. As a result of the rotary motion and the sliding surfaces 8a, 8b which are arranged opposite one another in respect of the opposing surfaces 9a, 9b, a first travel is produced with a travel from A-B, as shown in
To increase the total travel which is made up of the first and second travel, with the total travel being made up as follows:
Total-travel=Delta 1+Delta 2=(A−B)+(C−D),
the first and second opposing surfaces 9a, 9b are arranged such that a further maximum distance C and a further minimum distance D result for the formation of the ramp-shaped surface, see
| Number | Date | Country | Kind |
|---|---|---|---|
| 08017922.9 | Oct 2008 | EP | regional |
