NO813989L - DEVICE FOR ATTACHING A PROTECTION RING TO A D SECURITY - Google Patents

Description

The invention relates to a device for connecting a protective ring to a threaded sleeve in, for example, a diazed safety element.

When you use safety elements and have contact protections made of plate material, you must use some form of protective ring. It is then necessary to get this protective ring to sit securely in place, and to achieve an easy installation.

A common way to date is to have threads on the inside of the protective ring and screw this onto the threaded sleeve. However, this means that each protective ring must be screwed onto the threaded sleeve, and it should also not be screwed all the way to the bottom, as it may then be necessary to unscrew the ring a bit when the protective plate is to be installed. It is also expensive to produce such a protective ring in plastic material. It can also happen that the protective ring unscrews during installation and disappears, or alternatively becomes damaged.

There is also another solution to the problem where you use loose fastening details that are mounted on the outside of the threaded sleeve. You then avoid the problem with the threads on the inside of the protective ring. Instead, however, you get extra details to keep track of during assembly, and extra details to produce.

The invention relates to a solution to the above and other related problems and is characterized by the fact that the threaded sleeve in its upper part is provided with at least two tabs which are arranged preferably symmetrically around the circumference of the threaded sleeve and are produced from the same piece as the threaded sleeve, and that the protective ring is provided with an attachment that engages with the tabs.

By using tabs, you completely avoid the problem with the threads inside the protection ring as well

will be possible to produce in suitable plastic material. Installation is easy. You only need to press the protective ring into place and it is fixed. The clearance that is desired when mounting the protective plate is provided by means of the appropriate design of the protective ring

inside. By e.g. punching out the tabs of the threaded sleeve, the threaded sleeve and the tabs can be produced in one simple way in one piece - and avoids the trouble of several manufacturing and assembly parts, which was the case with the previous embodiment with one or more loose fastening details that are mounted on the outside of the threaded sleeve.

The most natural way to arrange the tabs is to arrange them in a direction mainly perpendicular to the threads of the threaded sleeve, as it is movement of the protective ring in this direction that must be prevented. However, it has been shown that it is very well possible to arrange the tabs in a direction essentially parallel to the threads as a small force is required to prevent the ring from moving in the direction in which the ring is put on. This arrangement of the tabs is preferable as it is the simplest in terms of manufacturing technology.

The inner, lower part of the protective ring is advantageously designed as a cone with an opening downwards and terminated upwards so that an edge is formed which forms an engagement with the tabs on the threaded sleeve. By making the downward opening on the protective ring so large that it goes outside the tabs, the protective ring can be pressed into place.

The invention will be described in more detail in the following with reference to the drawing, where fig. 1 shows a threaded sleeve and a protective ring seen from above, and fig. 2 shows a section through the protective ring and the threaded sleeve 1 side view when the protective ring is mounted on the threaded sleeve. The same reference numbers are used in both figures.

Fig. 2 shows the threaded sleeve with two bent tabs 2 and a protective ring 3. From fig. 2 clearly shows how the tabs 2 go over the shoulder 4 on the protective ring. When putting on protective rings, the tabs are forced against the threaded sleeve by the cone-shaped lower part of the protective ring. When the protective ring has been moved so far that the tabs have come past the shoulder 4 on the protective ring,

. springs the tabs out and in this way keeps the protective ring in place. By varying the distance between the approach 4

and the 2 side edges of the tabs, you can vary the clearance that is desired for mounting the protective plate. In the embodiment shown, the tabs are arranged highest on the threaded sleeve. This is of course not necessary, but one could imagine arranging the tabs significantly closer to the lower part of the threaded sleeve. You just have to make sure that the cone surface does not become steeper than the tabs can be bent in by this. If for some reason you want to remove the protective ring, you must somehow press the tabs 2 against the threaded sleeve and in this way get past the shoulder 4. This can be difficult, but it is a moment that rarely occurs, and the safety and simplicity of the device clearly outweighs the increasing difficulty of removing the protective ring. As it is a requirement that the protective ring must be on the device when it is energized, from this point of view it must be considered an advantage that the protective ring is difficult to remove.

The device described above is only an example of an embodiment, and the invention can of course be modified within the scope of the subsequent patent claims.