A pull cord and an element for a pull cord.

Abstract

 A pull cord for operating a switch which is mounted on or near a wall, which pull cord (8, 9) comprises an element (1, 2) having a cross dimension of more than 30 mm, which element (1, 2) keeps the part of the pull cord (9) which is present under said element (1, 2) spaced from the wall. The element (1, 2) may be spherical and can break when the pulling force in the pull cord (8, 9) exceeds a predetermined value.

Description

[0001] The invention relates to a pull cord for operating a switch which is mounted on or near a wall, and to an element which can be incorporated in such a pull cord. Especially when the switch is flush-mounted in a wall, the pull cord will often be space a small distance from the wall, which makes it difficult to take hold of the pull cord.

[0002] The objective of the invention is to provide a pull cord for a switch, which pull cord can easily be taken hold of, which is secured against excessive forces being exerted thereon and/or which has an attractive appearance.

[0003] In order to accomplish that objective, the pull cord comprises at least one element having a cross dimension of more than 30 mm, preferably more than 45 mm, which element is capable of keeping the part of the pull cord which is present under said element spaced from the wall. By incorporating such an element in the pull cord, and that at a point above the part of the pull cord which is taken hold of, the pull cord will be positioned some distance from the wall at the point where said taking hold of takes place, so that it can readily be grasped. Preferably, the element is substantially spherical, which not only provides an attractive appearance, but wherein a predetermined distance, namely half the diameter of the sphere or more, is maintained between the pull cord and the wall at all times.

[0004] In one preferred embodiment, the pull cord comprises more than one element of this kind, for example one near the switch and one near the end of the cord, so that said latter element can be taken hold of in order to pull at the cord. Furthermore it is possible to provide the cord with spherical elements of this kind in more than one places, in order to make it easier to take hold of the cord at different positions.

[0005] In one preferred embodiment, at least one of the elements comprises a break coupling, preferably an element which is incorporated in the upper part of tee pull cord. Said break coupling is constructed so that the element will divide into two parts when a predetermined force is exceeded, with one part of the pull cord being attached to each part.

[0006] Such a break coupling not only serves to prevent the switch or the pull cord from being damaged, but it also serves to prevent objects from being damaged or persons from being injured when the bottom end of the pull cord is attached, intentionally or unintentionally, to an object or to a person. Consider in this connection a hospital situation, with the bottom end of the pull cord being wound round parts of a bed or round an arm of a person in said bed, and the bed being moved out of the room.

[0007] Preferably, the element comprises two hemispheres, with one part of the pull cord being attached to each hemisphere, which hemispheres are interconnected by means of a snap connection, which snap connection will come loose when a predetermined force is exerted. The two hemispheres may be substantially identical in form thereby. A snap connection of this kind will be explained in more detail by means of an embodiment thereof.

[0008] In one preferred embodiment, each hemisphere is provided with a lip, which can extend to within the other hemisphere and which is capable of engaging in a recess in the inner wall of the other hemisphere, which lip is elastic and which can be pulled out of the recesses under deformation. The entire element is preferably made of plastic material, with the lips being formed integrally from said plastic material and being elastic to a certain extent.

[0009] The construction of such a snap connection is preferably such that there will be hardly any (elastic) deformation, if at all, of the material in the situation wherein the two hemispheres are interconnected, whilst the material will deform elastically when the two hemispheres are moved apart. In this manner, the material is not loaded during the, sometimes prolonged, period when the pull cord functions without the break coupling being operative. This is conducive towards the correct operation of the break coupling, also after it has not been used for a prolonged period of time.

[0010] In one preferred embodiment, the element comprises two hemispheres, which are substantially identical in form, and which are interconnected by means of a snap connection comprising two opposite lips on each hemisphere, which lips can extend into the other hemisphere and which are capable of engaging in recesses in the inner wall of the other hemisphere, which lips are elastic and which can be pulled out of the recesses under deformation, and wherein each hemisphere is provided with a hole, through which the pull cord can extend so as to be fixed within the hemisphere in question by means of a knot.

[0011] Preferably, information or an indication is provided on the element. Thus, the upper element of the pull cord may for example indicate what will happen when the pull cord is pulled at. The element may carry a picture of a nurse in the case that the pull cord is used to operate a switch, by means of which a nurse can be called. An arrow which points downwards may be present on the lower element in the pull cord to indicate that the pull cord can be pulled downwards there. Furthermore, different colours may be used for the elements to indicate different functions of a switch to be operated.

[0012] Further aspects of the pull cord and of the element, which can be used either separately or in combination with each other, will be described hereafter by means of an embodiment and be defined in the claims.

[0013] The invention will be explained in more detail hereafter with reference to the drawing, which shows an embodiment of an element which can be incorporated in a pull cord.

Figure 1 is a side view of an element;

Figure 2 is a plan view of an element, and

Figure 3 is a perspective view of the two halves of an element.

[0014] The figures are merely schematic illustrations, which show only one embodiment, to which many variations are possible.

[0015] Figure 1 shows a spherical element in side view, which element comprises an upper part 1 and a lower part 2. Both parts 1, 2 are identical in form, and they are made of plastic material.

[0016] The plan view of Figure 2 shows a hole 3, through which a pull cord 8, 9 can extend. In this manner, each part 1, 2 can be connected to one part of a pull cord 8, 9 by moving the end of said part of the pull cord through hole 3 to within the part 1, 2 and making a knot in the pull cord within part 1, 2. Figure 1 shows the two parts 8, 9 of a pull cord.

[0017] Figure 3 shows the manner in which the parts 1, 2 of the element are interconnected. This figure is a perspective view of the two parts 1, 2 of the element, which parts are spaced some distance apart.

[0018] The two parts 1, 2, which are identical in form, are each provided with two lips 4, which extend to outside the hemispherical part 1, 2 in question, and which extend to within the other part 2, 1 when the two parts 1, 2 are attached together.

[0019] In the situation wherein the two parts 1, 2 are attached together, a cam 5 which is present on lip 4 is positioned in a corresponding recess 6 in the inside surface of a part 2, 1 other than the part to which the lip in question is fixed.

[0020] The shape of cam 5 and/or the shape of recess 6 are selected so that the two parts 1, 2 can be detached from each other by exerting a sufficiently large pulling force. The magnitude of said pulling force is determined by the shape of cam 5 and the shape of recess 6, and by the spring force which is exerted by the lip. Said spring force can be determined by suitably selecting the shape and the dimension of the lip. The shape of lip 4, cam 5 and recess 6 is such that lip 4 is hardly deformed, if at all, when the two parts 1, 2 are attached together.

[0021] When the above-described element is incorporated in a pull cord by connecting parts of said pull cord to the parts 1, 2 of said element, wherein use is made of holes 3, the effect which is achieved is that the pull cord is kept spaced from a wall, because the element abuts against said wall, another effect which is achieved is the fact that the cord can easily be taken hold of, because the element functions as a handle, and yet another effect is the fact that the connection between parts of the cord will be broken when a predetermined pulling force is exceeded.

[0022] It is possible to provide a particular indication on the element by means of a picture or a colour. In Figure 1, the element is provided with a downwardly pointing arrow, which is a affixed to the element by means of a sticker, for example. Arrow 11 functions to indicate that the pull cord can be pulled at in downward direction.

[0023] In Figure 3, an illustration is present on part 2 of the element which indicates that the pull cord, to which the element is attached, is intended for operating a switch which controls the playing of music. Thus, a patient who is lying in bed in a hospital can operate a radio by means of the pull cord.

Claims

1. A pull cord for operating a switch which is mounted on or near a wall, which pull cord (8, 9) comprises an element (1, 2) having a cross dimension of more than 30 mm, preferably more than 45 mm, which element (1, 2) keeps the part of the pull cord (9) which is present under said element spaced from the wall.

2. A pull cord according to claim 1, characterized in that said element (1, 2) is substantially spherical.

3. A pull cord according to any one of the preceding claims, characterized in that said pull cord (8, 9) comprises more than one of said elements (1, 2), which are provided at spaced-apart positions.

4. A pull cord according to any one of the preceding claims, characterized in that an element as defined (1, 2) comprises a break coupling (5, 6), which will break when the pulling force in the pull cord (8, 9) exceeds a predetermined value.

5. A pull cord according to any one of the preceding claims, characterized in that an element as defined comprises two hemispheres (1, 2), with one part of the pull cord (8, 9) being attached to each hemisphere, which hemispheres are interconnected by means of a snap connection (4, 5, 6), which snap connection will come loose when a predetermined force is exerted.

6. A pull cord according to claim 5, characterized in that the two hemispheres (1, 2) are substantially identical in form.

7. A pull cord according to claim 5 or 6, characterized in that a hemisphere (1, 2) is provided with two lips (4), which can extend to within the other hemisphere (2, 1) and which are capable of engaging in recesses (6) in the inner wall of the other hemisphere (2, 1), which lips (4) are elastic and which can be pulled out of said recesses (6) under deformation.

8. A pull cord according to any one of the preceding claims, characterized in that the element (1, 2) is also an information carrier, on which a visible indication (11) is provided.

9. A element intended for being incorporated in a pull cord, which element (1, 2) comprises a break coupling (5, 6), which will break when the pulling force in said pull cord exceeds a predetermined value.

10. An element intended for being incorporated in a pull cord, which element (1, 2) is substantially spherical.

11. An element according to claim 9 or 10, characterized in that said element comprises two hemispheres (1, 2) which can be interconnected, wherein each hemisphere comprises means (3) for fixing one end of one part of the cord (8, 9).

12. An element according to any one of the claims 9 - 11, characterized in that said element comprises two hemispheres (1, 2), which are substantially identical in form, and which are interconnected by means of a snap connection comprising at least two lips (4) on each hemisphere, which are capable of engaging in recesses (6) in the other hemisphere (2, 1).

13. An element according to any one of the claims 9 - 12, characterized in that the element comprises two hemispheres (1, 2), which are substantially identical in form, and which are interconnected by means of a snap connection comprising two opposite lips (4) on each hemisphere (1, 2), which lips (4) can extend into the other hemisphere (2, 1) and which are capable of engaging in recesses (6) in the inner wall of the other hemisphere (2, 1), which lips (4) are elastic and which can be pulled out of said recesses (6) under deformation, and in that each hemisphere (1, 2) is provided with a hole (3), through which the pull cord (8, 9) can extend.

14. An element according to any one of the preceding claims, characterized in that said element (1, 2) is also an information carrier, on which a visible indication (11) is provided.

Drawing