Patent Publication Number: US-6209405-B1

Title: Apparatus for transferring a carrier for shelves, cupboards, tables or the like along a path

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a device for moving a support for shelves, cupboards, tables or similar along a path, which support is suspended on an arm that is pivotally connected to a base, for example a wall, in an axis of rotation at one end of the arm. 
     2. Description of the Related Art 
     Devices of this type are used chiefly to lower shelves and cupboards from a position high up on a wall to a position lower down in order to facilitate access by disabled persons, for example, to articles placed high up. A typical area of application is the raising and lowering of shelves in an overhead cupboard in a kitchen. 
     A number of such devices are known. Reference shall be made, for example, to NO-163 162, DE-1 554 464, DE-3 215 572, DE-3 914 307, DE-2 721 307, EP 242811, EP 661015, EP 402283, DE-3 635 592, DE 2 919 610, DE-3 433 137 and DE-2 524 406. The devices according to these publications function for the most part either in that the cupboard or shelves are guided vertically, or in some cases slantwise, on rails or by means of arms of parallelogram configuration. These raising and lowering devices are set to guide the cupboard/shelves along a fixed path, which in the case of the rail-guided devices is a straight line, in the case of the devices which make use of arms of parallelogram configuration it is a circular arc. The path which the cupboard/shelves follow is fixed once and for all when the device is installed. 
     With the known devices it is not possible to lower an overhead cupboard below the level of the kitchen counter. Rail guides running on the outside of the kitchen counter would not be practical as these would prevent normal use of the kitchen counter. Nor do the parallelogram-guided devices provide any possibility of lowering, for example, an overhead cupboard below the kitchen counter. The lowering facility is limited by the length of arms, which in turn is limited by the height of the ceiling or the depth of the cupboard. For many disabled persons this may be insufficient to enable them to reach the top shelves in the overhead cupboard. 
     The raising and lowering devices, which function with the aid having a arms of parallelogram configuration, have arms consisting of several links, which inevitably results in a certain slack and above all the danger of the arms “scissoring” the wrong way when the arms assume a position parallel to or almost parallel to one another. A second problem with the parallelogram mechanism is that when the sides (the arms) of the parallelogram approach one another a great moment of force is exerted on the drive mechanism. The drive mechanism must therefore be dimensioned so as to be very strong or, alternatively, the moment of force must be compensated by means of weights or springs. Since the moment of force varies greatly depending upon the weight of the shelves, the weight or springs will not be able to compensate satisfactorily. 
     SUMMARY OF THE INVENTION 
     The objective of the present invention is to provide a device which allows the lowering of an overhead cupboard, for example, to a point below and optionally outside the plane of the kitchen counter and provides secure guiding of the cupboard/shelves without there arising any danger of the arms “scissoring” the wrong way or inadvertently “locking”, and without the occurrence of any significant moment of force. This is achieved by means of a device having the characterising features hereinbelow. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The invention will now be described in more detail with reference to the accompanying drawings, wherein: 
     FIG. 1 illustrates a first embodiment of the invention in perspective and in detail; 
     FIGS. 2 a - 2   d  show the device schematically according to a first embodiment of the invention in four different positions; 
     FIGS. 3 a  and  3   b  show the device schematically according to the first embodiment of the invention adjusted for greater lowering height; 
     FIG. 4 illustrates the device schematically according to the invention in a second embodiment; 
     FIGS. 5 a - 5   c  show the device schematically according to the second embodiment of the invention in three different positions; and 
     FIG. 6 shows a third embodiment of the invention schematically presented in two different positions. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     FIG. 1 is a perspective view of the principal details of a first embodiment of the device according to the invention, shown partially in section. The device consists inter alia of a first arm  1  and optionally a second arm (not shown) spaced apart therefrom. A support  2 , of which one half is shown in FIG. 1, is suspended between the first arm  1  and the second arm. The support  2  can be designed, for example, to support a number of shelves (not shown in FIG.  1 ), and for this purpose is equipped with a shelf supporting rail  3 , wherein grooves  4  are formed for the insertion of shelves at different levels. The shelf supporting rail  3  is suspended in a support shaft  5  which extends between the first arm  1  and the second arm. The first arm  1  and the second arm may be constructed so as to be identical, but do not necessarily need to be so, as the mechanism which will be described below only needs to be provided in the first arm  1 . In this case, the second arm will function as a “slave” and follow the movement of the first arm. 
     In the first arm  1 , a mechanism is provided which ensures, for example, that the shelves maintain the right position when the arm  1  is swung outwards and downwards. The arm  1  is thus mounted about an axis of rotation  6 . This can be done, for example as is shown in FIG. 1, in that the arm is fixedly connected to a sleeve shaft  7  which is rotatably mounted on a shaft  8 , which in turn is fixedly connected to a base  9 , for example a cupboard bottom, via brackets  10 . In order to turn the arm there may be provided, for example, an electric motor  11  which, via a cogwheel  12 , is designed to rotate the sleeve shaft  7  and thereby turn the arm  7  about the axis of rotation  6 . 
     A cogwheel  13  is fixedly connected to the shaft  8  and thus is in a non-moveable relation to the base  9 . Over the cogwheel  13  there extends an endless chain  14  which, as can be seen in FIG. 1, may be positioned inside a cavity in the arm  1  and extend the length thereof. Via a redirectioning wheel  15 , the chain  14  extends along the arm up to a cogwheel  16 , which is fixedly connected to the shaft  5 . The chain  14  extends further over a reversing wheel  17 , equipped with a tensioning device to tension the chain  14 , and back to the cogwheel  13  via a redirecting member  24  (i.e. sprocket, or optionally a fixed arcuate member) at the bend or  18  of the arm  1 . 
     The support  2  is slideably mounted with respect to arm  1  as shown, in such a way that the cogwheel  16  and the shaft  5  can be displaced along the arm. For this purpose a slot  26  is formed in the arm  1 . Shaft  5  can be displaced along arm  1  by disconnecting plate  27  which is rotatably attached thereto, moving chain  14  out of mesh with cogwheel  16 , and sliding shaft  5  and plate  27  to a different position along arm  1 . Plate  27  may be releasably attached to arm  1  by known means such as bolts (not shown) positioned in bolt holes  27   a  or alternative releasable fasteners. After sliding shaft  5  and plate  27  to a different position, reattachment of plate  27  to arm  1  can also be provided in any known manner, as by providing a plurality of bolt holes or slots in arm  1  for reception of bolts, screws or the like. The shelf supporting rail  3  may also be slideably mounted on the shaft  5 . 
     In FIGS. 2 a - 2   d  the function of the arm is shown, where FIG. 2 a  shows the arm  1  having been turned a little forward from a starting position where the arm is turned right back to the left in FIG. 2 a  and is inside a cupboard  25 . Since the cogwheel  13  is non-rotationally connected to the base  9  the chain  14  will be retained by the cogwheel  13 . The movement of the arm  1  will thereby be transmitted via the cogwheel  13  to the cogwheel  16  and cause this to be retained in the same rotational position relative to the cogwheel  13  and the base  9 , i.e., the cogwheel  16  will not rotate about its axis. Thus, the support  2  is also held in the same position relative to the vertical plane when the arm  1  moves forwards and downwards. 
     In FIG. 2 b  the arm  1  has moved outwards so that the upper part of the arm I is now horizontal. The support  2  has now moved a small distance outwards but vertically to an insignificant degree. In FIG. 2 c  the arm  1  has moved quite some distance downwards and the support  2  has moved likewise. In FIG. 2 d  the outermost part of the arm  1  is pointing vertically downwards, and the support  2  is now positioned considerably lower than in the starting position. However it is still vertical, so that the shelves are held in a horizontal position. In the case illustrated in FIG. 2 d  the support  2  has been lowered so that its lower end rests on a counter surface  20 . However, it is also possible to lower the support  2  so that its lower end comes to rest some distance below and thus also outside the counter surface  20 . This is shown in FIGS. 3 a  and  3   b . Here, the cogwheel  16  has been displaced along the arm  1  towards the free end thereof. In practice, this is done by slackening the chain  14  so that it can be brought out of mesh with the cogwheel  16 , thereby enabling the cogwheel  16  to be displaced in the slot  26 . At the same time, the support  2  is lowered relative to the cogwheel  16  in that the shelf supporting rail is lowered relative to the shaft  5 , so that the upper end of the support assumes approximately the same height when the arm  1  is in the starting position as is the case in the situation in FIGS. 2 a - 2   d.  However, when, on the other hand, the arm  1  is swung out and down to the position shown in FIG. 3 b,  the support  2  will depend from the arm  1  to a far greater extent than in the situation shown in FIG. 2 d.  In this way the shelves  19  will be capable of being positioned outside and below the counter surface  20 . 
     In FIG. 4 a second embodiment of the device according to the invention is shown. Here, the arm is not L-shaped but straight. The cogwheel  13  in FIG. 4 corresponds to the cogwheel  13  in the preceding embodiment. It is also fixedly connected to a base  9 . However, in this case the support  2   a  is connected to a cogwheel  16   d  at the free end of the arm  1   a  opposite the cogwheel  13   a . The cogwheel  16   d  here has the same function as the cogwheel  16  in the preceding embodiment and also the function of the reversing wheel  17 . 
     This embodiment is best suited for lowering whole cupboards down from a high position on a wall. Here, instead of the operation of the arm  1   a  at its axis of rotation, a motor  21  is provided secured to the wall above the axis of rotation, and preferably also above the free end of the arm  1   a,  whence a wire  22  extends down to the front edge of the cupboard. This is shown in FIGS. 5 a - 5   c.  In FIG. 5 a  the arm  1  is in the starting position. When the wire  22  is slackened the cupboard  23  will be lowered towards the floor. Since the cogwheel  16   e , which is fixedly connected to the cupboard  23 , cannot rotate relative to the cogwheel  13   a  and thus also the wall, the cupboard  23  will be held in the same orientation relative to the wall whilst it is being lowered. In FIG. 5 b  the cupboard  23  is lowered down to the floor approximately immediately below the position it had on the wall in the starting position. However, in FIG. 5 c  the axis of rotation of the arm  1  is located at a lower point so that the cupboard comes to rest further out from the wall in its lowered position. This makes it possible to lower the cupboard outside a table or another cupboard (not shown) positioned on the floor against the wall. 
     In FIG. 6 a third embodiment of the device according to the invention is shown, where three cogwheels  16   a,    16   b  and  16   c  are in mesh with the chain  14 , which in turn is in mesh with the cogwheel  13 , which here too is fixedly connected to the base  9 . Thus, the cogwheels  16   a,    16   b  and  16   c  will not be able to rotate relative to the cogwheel  13 . When the arm, which is not shown here in order to facilitate understanding of the drawing, is lowered to the position which is indicated by means of the broken line on FIG. 6, the shelves  19   a,    19   b  and  19   c  will have changed places with one another. Nevertheless, throughout the movement of the arm they will be held in a horizontal position. 
     Although in the above embodiments of the invention have been described where an endless chain is used to retain the rotation of the cogwheel  16  relative to the cogwheel  13 , other means may also conceivably be used to transmit these loads. Belts, straps, tapes and similar are obvious. Within the scope of the invention, however, there is also a possibility of using shafts having conical cogwheels at each end. The cogwheels  13  and  16  must then, of course, also be conical. By arranging the cogwheel  16  slideably on the shaft, this embodiment will provide the same possibilities for adjustment as if a chain or similar were being used. 
     Although in the above embodiments have been shown where the support is held in the same position relative to the vertical plane during the movement of the arm, it is also within the scope of the invention to be able to alter this position during the movement of the arm. This can be done, for example, by providing a gear between the cogwheel  13  and  16  which is different from one to one. It is also possible to arrange the cogwheel  13  so that it is capable of being rotated relative to the base  9 , e.g., with the aid of a motor, so that by turning the cogwheel  13  the cogwheel  16  is caused to turn, resulting in an alteration of the position of the support  2 . Other modifications are also conceivable within the scope of the patent claims below, and in particular independent patent claim  1  below.