Spring device, e.g. for the leg of a children's bed.
Technical Field of the Invention
The present invention relates to a spring device, preferably adapted to be used as an accessory to a child's bed, said device comprising a compression spring means and a fastening means, by which the compression spring means is adapted to be attached to an element, preferably a leg of a child's bed, said fastening means being provided in the area of one end of the compression spring means.
Prior Art
It is previously known to provide child's beds, preferably such beds that have four legs, with compression springs that are attached to the ends of the legs that are adapted to rest against an underlying surface. The springs are arranged in such a way that the spring action of the springs is in the longitudinal direction of the legs.
An example of such a previously known structural design is disclosed in FR 670.420, said document showing a compression spring that is attached to the leg of for instance a bed. However, this structural design has the disadvantage of not being childproof, i.e. it does not have an effective protection against the risk that a child may hurt oneself when being in contact with the structural design in question, e.g. the child may pinch a finger between two adjacent turns of the spring .
From FR 1.108.356 is previously known a spring arrangement in connection with a leg, said arrangement in principle seeming to be childproof. However, the spring is recessed in the leg and a relatively extensive measure in the leg is required, regardless if the spring arrangement is mounted in connection with the manufacturing of the leg or subsequently.
Objects and Features of the Invention
A primary object of the present invention is to define a device that is made childproof in an effective way.
A further object of the present invention is that the function of the spring device should not be negatively affected by the fact that the spring device is childproof.
Still an object of the present invention is that the spring device may be subsequently mounted on child's beds in a simple and functionally safe way.
Still a further object of the present invention is that when the spring device is mounted on a child's bed it should impart a new moving action to said bed, said moving action may be used in connection with putting a child to sleep.
Brief Description of the Drawings
Below embodiments of the invention will be described, reference being made to the accompanying drawings, where: Figure 1 shows a perspective view from above of an e bodiment of a spring device according to the present invention; Figure 2 shows a perspective view from below of the spring device according to figure 1; Figure 3 shows a side view of a cot with bars, upon whose legs spring devices according to the present invention have been mounted ; Figure 4 shows a detail of the lower end of a leg of the cot with bars, a spring device according to the present invention being mounted on said leg, the casing of said device being sectioned for reasons of clarity; Figure 5-
Figure 7 show three different embodiments of the casing of the device, said casings being sectioned.
Detailed Description of Embodiments of the Spring Device According to the Present Invention
The spring device shown in figures 1 and 2 comprises a casing 1, which in the disclosed embodiment is transparent, i.e. translucent. The casing 1 is manufactured from a flexible material, this will however be discussed more in detail below. The design in detail of said casing 1 is most evident from figure 5, reference being made to said figure. In its upper portion 3 the casing 1 has a spherical shape and
in its lower portion 5 a funnel like shape, said two portions being integrated with each other, i.e. the casing 1 is in one piece. In the area where the two portions meet the casing 1 is provided with a waist 7. The casing 1 has a first hole 9 at its highest point, the function of said first hole 9 will be described below. In its upper, spherical part 3 the shown embodiment of the casing has two second holes 10 that are located diametrically relative to each other.
Reference is again made to figures 1 and 2 in order to continue the description of the spring device according to the present invention. Said device also comprises a helical spring 11 that is received/mounted inside the casing 1. The helical spring is of the type compression spring, i.e. it tends to counteract its compression, and is in the shown embodiment designed in such a way that its upper end defines an opening that receives a screw 12, normally a wood screw, that also is part of the spring device according to the present invention. When the spring 11 is mounted inside the casing 1 the screw 12 extends through the first opening 9, see figure 5, of the casing 1.
In the embodiment according to figures 1 and 2 the spring 11 is designed in such a way that its outer contour is widened in direction towards its lower end. This means that the lower turns of the spring 11 define essentially larger diameters than the turns that are located adjacent to the screw 12. As is most evident from figure 2 the lowest turn of the spring 11 adjoin to the internal diameter of the casing 1 in the area of the free end of the funnel shaped portion 5. Said lowest turn is preferably designed in such a way that it defines an essentially annular contact surface that is located essentially in a plane perpendicular to the axial longitudinal axis of the spring. Due to the fact that said annular contact surface defines a relatively seen large diameter the stability of the spring device becomes satisfactory. The spring 11 and the casing 1 are normally not connected to each other.
The spring 11 has an axial extension, see also figure 4, that corresponds to the axially extension of the casing 1. This is an extremely important feature from the childproof aspect. Since the casing 1 externally surrounds the spring 11
along its entire axial extension, both when the spring has maximum axial extension and when it is compressed, it is to a large extent guaranteed that unwanted access to the spring 11 will not take place. In figure 3 is schematically shown how two spring devices according to the present invention are mounted at the lower ends of two legs 13 of a cot with bars. Normally, there are of course two further spring devices according to the present invention mounted at the lower ends of the legs that are not shown in figure 3.
In figure 4 is schematically shown how the screw 12 of the spring device according to the present invention is screwed into the leg 13. In connection with the mounting of the spring device according to the present invention it may be suitable to pre-drill a hole in the leg 13 for the screw 12. As is evident from figure 4 the screw 12 is inserted so far into the leg 13 that the casing 1, in the area of the first hole 9, in principle abuts against the lower free end of the leg 13. As is indicated by the dash dotted lines in figure 3 the mounting of the spring devices according to the present invention on a cot with bars means that a new moving action is imparted to said cot with bars, i.e. the bed may be rocked by means of an externally applied force that activates said spring devices . Apart from the fact that the new moving action of the bed may be used in connection with putting a child to sleep, said new moving action may be used in other circumstances. The rocking motion may be generated by a child itself that is in the bed and performs a motion, for instance jumping or sidewards moving.
When the cot with bars according to figure 3 performs its rocking motion the spring 11 of the four spring devices will alternate between a compressed state and an expanded state. This means that the axial extension of the casing 1 will vary in accordance with the variation of the axial extension of the spring 11. When the spring 11 is compressed in axial direction also the casing 1 will be compressed in axial direction. Since it also is preferable that the free funnel shaped end of the casing 1 has a permanent, tight
contact against the underlying surface the two second holes 10 has the function that when the casing 1 is compressed in axial direction a certain amount of the air inside the casing 1 may flow out through said second hole 10. When the casing 1 again expands in axial direction, in connection with the spring 11 expanding in axial direction, air is sucked in through said second hole 10. This way of function is then repeated cyclically as long as the spring means according to the present invention are activated. Three embodiments of the casing 1; 1'; 1" are shown in section in figures 5-7, said casing being a part of the spring device. The casing 1, shown in figure 5, corresponds to the casing according to figures 1, 2 and 4. The casing 1 has in principle uniform wall thickness and is manufactured by so- called dip casting that is an essentially cheaper manufacturing method than injection moulding. However, dip casting has certain restrictions as regards the choice of material. Feasible materials are natural rubber (latex) and PVC. From environmental aspects latex is preferred, but the casing may not be made transparent by such a choice of material .
The casings 1' and 1" respectively, shown in figures 6 and 7, have somewhat thickened wall portions in the area of the air holes 10 and are adapted to be manufactured by injection moulding. The most preferred embodiment in this respect is shown in figure 6, however there might be some problems in connection with the form stripping. The embodiment shown in figure 7, i.e. a somewhat further thickened wall portion in the area of the air holes 10, is estimated to be more favourable as regards form stripping. The injection moulded casings 1' and 1" are preferably manufactured from soft thermoplastic. Said casings 1' and 1" may be transparent .
Feasible Modifications of the Invention
The three embodiments of the casing that is included in the device according to the invention have in principle the same basic shape, i.e. a spherical portion, a waist and a funnel shaped portion. However, within the scope of the
present invention it is feasible to have casings with a completely different basic shape, and in exemplifying and non- restricting purpose the following alternative basic shapes of the casing may be mentioned: completely spherical, egg shaped, cylindrical, segment of a sphere and suction cup shaped. Also in this case the wall thickness may be uniform or varying.
In the embodiment described above the compression spring means constitutes a helical spring that has a widening shape towards the open end of the casing 1; 1 ' ; 1". However, within the scope of the invention it is feasible to have helical springs of a different shape, e.g. cylindrical. Within the scope of the invention it is also feasible to use other types of compression spring means, e.g. a gas spring.
In figure 3 above the spring device according to the present invention is shown mounted on the legs of a cot with bars. Of course the device according to the present invention may also be used in connection with beds that are void of legs but have a different type of support that rests upon an underlying surface, i.e. a skirting or the like. In such a case the number of devices according to the present invention may be mounted on said alternative support in order to give also such a bed the corresponding characteristics as the cot with bars according to figure 3.
As is most evident from figure 2 the lowest turn of the spring 11 contacts the underlying surface. If it is preferable that no direct contact occurs between the spring 11 and the underlying surface it is feasible that the device according to the invention at its bottom is provided with a soft floor-protector having a diameter that is large enough to receive at least the diameter of said lowest turn. Within the scope of the present invention it is also feasible to design the casing in such a way that it at its free end is provided with an inwardly folded collar that in active position of the device according to the invention is located between the lowest turn of the spring and the underlying surface.
The spring device according to the present invention is neither restricted to be used in connection with child's beds but alternative fields of use are feasible when it is desirable that an object is given a spring support relative to
an underlying surface. Apart from furniture, toys may be mentioned in exemplifying and non-restricting purpose. Regardless of area of application, the spring device according to the present invention should generally be childproof.