Abstract:
An apparatus for applying an optional number of weight disks on a dumbbell includes a base unit, a first and second set of separate weight disks and a handle. The base unit has a first and second group of retainers which support the first and second set of weight disks. On the handle, a selectable number of weight disks are disposed from the first and second set of weight disks. The weight disks have openings which are closed towards the peripheries of the weight disks. The handle has pin devices which are axially projectable in opposing directions for insertion in the openings of the weight disks. The projection of the pin devices out of the handle is selectable for adaptation of the length of the pin device to the number of weight disks that are to be secured on the handle. The pin devices are further lockable with locks, in selected projectional positions in relation to the handle, and have, on their free ends, locks for fixedly retaining the selected number of weight disks.

Description:
BACKGROUND AND SUMMARY 
       [0001]    The present invention relates to an apparatus for applying an optional number of weight disks on a dumbbell, and comprising a base unit with a first and second group of retainer means which are designed for cooperation with a first and a second set, respectively, of upright weight disks, a first and second set of separate weight disks, the weight disks having openings that are closed towards the periphery of the weight disks and that are disposed substantially along a straight line on the cooperation of the weight disks with the retainer means, a handle with pin devices axially projectable in opposing directions for insertion in the openings of the weight disks, the projection of the pin devices out of the handle being selectable in order thereby to permit the choice of the number of weight disks accommodated on the handle, and locking means by which the pin devices are lockable in selected projectional positions in relation to the handle. 
         [0002]    A dumbbell in its simplest form is of one piece manufacture and has a handle with a weight at each end. For example, the material of the dumbbell may be cast iron. 
         [0003]    A dumbbell of this simple type functions quite excellently as an exercise implement as long as the weight of the dumbbell does not need to be changed. If there were to be needs to this end, dumbbells of different weights are required, perhaps a relatively large number of different dumbbells. Naturally, this implies a considerable drawback. 
         [0004]    Dumbbells are also previously known in the art which include loose weight disks that may be placed in an optional number and in optional sizes on one and the same handle. For securing such loose weight disks, use may be made of different fixing means which are typically placed outside the weight disks and are locked in position there, A dumbbell of this type is perceived as impractical, since many different working phases and manual operations are required on mounting or dismounting of the weight disks and securing of the fixing means. 
         [0005]    Dumbbells are also previously known in the art where a number of weight disks standing on edge are placed in a specific holder or cassette. The weight disks have central openings but also grooves extending out from the openings to their periphery. The handle has an inner rotary shaft on whose outside a tube is disposed. Within both of the regions where the weight disks are located in the cassette, a part of the periphery of the tube has been removed so that the outer transverse dimensions of the tube at the removed peripheral area are less than the width of the grooves in the weight disks so that, as a result, the handle may be moved down through the grooves in to the central openings in the weight disks. This opening has a diameter which largely corresponds to the outer diameter of the tube. 
         [0006]    The shaft disposed interiorly in the tube has, in the regions of the weight disks, a number of bevels which, in the axial direction, are of different lengths and which are distributed along the circumferential direction. By rotating the shaft interiorly in the tube, the non-bevelled portions on the shaft may be rotated up to the position where the periphery of the tube has been removed in order thereby to extend radially outwards and constitute a locking device for the weight disks. As a result of the different axial length of the bevels of the shaft, it is possible, by a selection of the angle of rotation of the shaft, to select the number of weight disks on the dumbbell. A construction of this type is disclosed in U.S. Pat. No. 5,839,997. 
         [0007]    Naturally, the construction according to this US patent Specification facilitates mounting of an optional number of weight disks on a dumbbell. However, there are considerable drawbacks. One such drawback is the complicated mechanical construction, another is the fact that the weight disks, because of the presence of the radial recesses or grooves, will not have their mass distributed rotationally symmetrically around the handle. The radial recesses or grooves may possibly also entail a problem in mechanical strength if a heavy dumbbell is dropped on, for example, a concrete floor. 
         [0008]    It is desirable to design the apparatus intimated by way of introduction so that the drawbacks in the prior art technology are obviated. In particular, it is desirable to design the apparatus so that an optional number of weight disks, in a simple and convenient—but above all safe—manner can be applied on a dumbbell. It is further desirable to design the apparatus intimated by way of introduction so that it displays high mechanical strength and can be manufactured at low cost. 
         [0009]    In an apparatus according to an aspect of the present invention, locking means further include disk locking devices by means of which the number of weight disks defined by the projectional position are lockable on each respective pin device, the disk locking devices being disposed at the free ends of the pin devices, and have locking positions where they are located axially outside surface areas on the outermost weight disks, these surface areas surrounding the openings of the weight disks. 
     
    
     
       BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS 
         [0010]    The present invention will now be described in greater detail hereinbelow, with reference to the accompanying Drawings. In the accompanying Drawings: 
           [0011]      FIG. 1  shows in perspective an apparatus according to the present invention, certain parts and details having been cut-away for purposes of clarity; 
           [0012]      FIG. 2  shows a part of a base unit included in the present invention and a handle lying thereon in the partly cut-away state; 
           [0013]      FIG. 3  shows in perspective the part of the handle in the cut-away state shown in  FIG. 2 ; 
           [0014]      FIG. 4  shows a component included in the handle in the longitudinally retracted state; 
           [0015]      FIG. 5  shows the component illustrated in  FIG. 4  in the longitudinally projected state; 
           [0016]      FIG. 6  shows a pin device disposed interiorly in the component according to  FIG. 4 ; and 
           [0017]      FIG. 7  shows the pin device according to  FIG. 6  in the cut-away state. 
       
    
    
     DETAILED DESCRIPTION 
       [0018]    As will apparent from  FIG. 1 , the apparatus according to the present invention includes a base unit or cassette  1  which has a number of retainer means  2  in the form of preferably circular grooves in which the weight disks  3  may be lodged standing on edge. The weight disks are separate and are not permanently interconnected to one another. In addition, the apparatus according to the present invention includes a handle  4  which is to form part of a dumbbell with an optional number of the weight disks  3  standing in the base unit  1  and which is of a construction which will be described in greater detail hereinbelow. It will also be apparent from  FIG. 1  that the handle  4  has, at its opposing ends or in conjunction with the weight disks  3 , housing means  5  which will also be described in greater detail hereinbelow. 
         [0019]    The circular grooves  2  have a somewhat non-circular section, for example a planar section. If the weight disks have a corresponding non-circular section, it is possible that all weight disks can be given the same position in the rotational direction, i.e. about their centre axis. 
         [0020]    In  FIG. 1 , all weight disks  3  have been shown as of equal size, but the weight disks may naturally be of differing size and weight, where the weight may be varied by choices of different materials in the weight disks. 
         [0021]    It will be apparent from  FIG. 1  that the weight disks have through-going openings  6  which, if the disks are circular, are preferably placed in the centre of the disks. The openings  6  are closed and have no communication with the peripheral areas of the weight disks. In one practical embodiment, the openings  6  may be circular. In an alternative embodiment, they may be of a different shape. 
         [0022]    It will further be apparent from  FIG. 1  that pin devices  7  extend from the handle  4  and also out from both of the housing means  5 , the pin devices being accommodated in the openings  6  of the weight disks  3 . In order for the pin devices  7  to be insertable in the openings  6  of the weight disks  3 , it is important that the openings  6 , when the weight disks  3  cooperate with the retainer means  2  in the base unit, be located along a common, straight line so that they together form a channel for accommodating the pin devices. 
         [0023]    The pin devices  7  are disposed in the handle  4  in such a manner that, from opposing end regions of the handle and out from both of the housing means  5  of the handle, they are axially projectable to optional projection lengths on the outside of the two housing means  5 . By a variation of the axial projection of the pin devices  7 , they can extend out through an optional number of weight disks  3 . In  FIG. 1 , the pin devices  7  are shown in their maximum projectional position so that they extend through all of the weight disks  3 . On the other hand, in  FIG. 2  the pin devices are shown in but partly projecting positions and it will be readily perceived that, with the projection length displayed by the pin devices in  FIG. 1 , only two or possibly three weight disks will have room on the pin device. The same projectional length is shown for the pin device in  FIG. 3 . 
         [0024]    It will further be apparent from  FIG. 1  that, with the pin devices  7  projecting into an optional number of weight disks, it is possible by lifting of the handle in an upward direction, to lift out the selected number of weight disks on the dumbbell out of the base unit or cassette  1 , since the retainer means  2  are designed as at least partly circular, upwardly open grooves. 
         [0025]    In order to prevent the weight disks accommodated on the handle  4  or more particularly the weight disks accommodated on the pin devices from falling off, the handle  4  is provided with locking means by means of which the pin devices  7  are lockable in selected projectional positions and, in addition, the number of weight disks defined by the projectional position is fixedly lockable on each respective pin device  7 . From this it follows that the locking means must have component which, on the one hand, lock the pin devices in selected projectional positions and, on the other hand, are placed at the outer, opposing ends of the pin devices in order to lock at least the outermost weight disk  3  on the handle. To this end, the locking means include disk locking devices  8  which are transferable to locking positions when they are located axially outside surface portions on the outermost weight disks  3 , these surface portions wholly or partly surrounding the openings  6  of the weight disks. The disk locking devices also have inactive positions where they do not prevent axial movements of the pin devices  7  through the openings  6  of the weight disks. 
         [0026]    Principally from  FIGS. 2 and 3 , but also to some extent from  FIG. 1 , it will be apparent, as intimated above, that the pin devices  7  have, at their outer ends, a number, preferably four, of disk locking devices  8  which are spring biased in a radial outward direction so that, without being acted on, they extend radially outside the circumferential surfaces of the pin devices  7 . These disk locking devices  8  are also lockable in their radially outer positions so that, in the locked position, they cannot be pressed radially inwards. 
         [0027]    As was mentioned above, the weight disks  3  have openings  6  for the pin devices  7 . For cooperation with the disk locking devices  8 , the weight disks have, on both their insides and their outsides, bevels which form conical or correspondingly shaped entry surfaces for impression of the disk locking devices  8 . In  FIG. 1 , these bevels located on the outside of the weight disks  3  have been given reference numeral  9 . 
         [0028]    The above disclosures imply that if a handle  4  is placed in the base unit  1 , which is provided with two sets of weight disks, one on each side of the handle  4 , and thereafter the pin devices  7  are projected out axially in opposite directions, the disk locking devices  8  will strike the bevels on the insides of both of the innermost weight disks  3 . When the axial projection of the pin devices  7  continues, the disk locking devices  8  are urged radially inwards in order once again to move outwards when they have passed the narrowest dimension of the openings. This cycle will be repeated if the projection movement of the pin devices continues. 
         [0029]    It will be apparent from  FIGS. 4 and 5  that both of the pin devices  7  are telescopically accommodated in an outer sleeve  10  which is disposed interiorly in the handle  4 . Between the two pin devices  7  and the outer sleeve  10 , there is disposed a screw or worm mechanism, which is disposed, when the outer sleeve  10  is rotated in relation to the two pin devices  7 , to ensure that the pin devices  7  are projected into or drawn in opposing axial directions depending on the direction of rotation of the outer sleeve. In this context, it should be observed that both of the pin devices  7  are rotationally locked in both of the housing means  5  of the handle, which in turn are rotationally locked in the base unit  1 . Outside the outer sleeve  10 , there is provided a suitable surface cladding, for example a hose-shaped gripping section (not shown in  FIGS. 4 and 5 ). 
         [0030]    In the illustrated embodiment, the screw or worm mechanism includes two helically disposed grooves  11  which are through-going accommodated in the outer sleeve  10 . In these grooves, there are pins or bearing rollers  12  which are secured in the pin devices  7 . It will be readily perceived that if the pin devices are kept rotationally locked while, on the other hand the outer sleeve  10  is rotated, an axial displacement of the pin devices  7  will take place. The pitches of the helical or spiral grooves  11  are opposed so that thereby the direction of movement of the two pin devices  7  will also be opposed. 
         [0031]    In order to obtain defined projectional positions for the two pin devices  7 , there is an indexing device provided in the housing means  5  which only permits certain angles of rotation of the handle  4 , in particular its outer sleeve  10 , in relation to the housing means  5  and thereby also in relation to the base unit  1  and the pin devices. This indexing device includes a star pinion  13  (see  FIG. 3 ) which is non-rotationally united with the outer sleeve  10  and against which abuts a spring-biased ball  14  which is disposed in a corresponding bore in each housing means  5 . In such instance, the star pinion  13  is formed in such a manner that one rotational step corresponds to a change of the projection of the pin devices  7  which is equal in size to the thickness of the weight disks  3 . This implies that, starting from wholly retracted pin devices, after one rotational step, one weight disk will be disposed on each of the projecting pin devices  7  while, after two rotational steps, two weight disks will be accommodated on the pin devices  7 , and so on. 
         [0032]    In order to show how far the handle  4 , in particular the outer sleeve  10 , has been rotated, the outer sleeve has an indicator with a number of  FIG. 15  along its periphery, these figures being readable through a window  16  in the housing means  5 . It is thus very simple to twist the handle  4  as many rotational steps as the desired number of weight disks on the pin devices. 
         [0033]      FIGS. 6 and 7  show a pin device  7  with the pins  12  disposed thereon. The above-considered disk locking devices  8  will also be apparent. It will be apparent from the Drawing Figures taken as a whole that each pin device has a sleeve  17  with a longitudinal, axial groove  18 . Interiorly in the sleeve  17 , there is disposed a shaft  19  which is displaceable in the axial direction and which has a number of circumferential grooves  20  which are exposed through the longitudinal groove  18  in the sleeve  17  of the pin devices. The shaft  19  is urged by means of a spring  21  in a direction towards the disk locking devices  8 . 
         [0034]    It will be apparent from  FIG. 3  that there is disposed interiorly in each housing means  5  a pin lock  22  which is included in the locking means mentioned by way of introduction. Both of the pin locks  22  each have a projection  23  which may extend down through the longitudinal groove  18  of the pin devices  7  in order to snap down into one of the circumferential grooves  20  in the shafts  19 . In such instance, the distance between neighbouring circumferential grooves  20  in the shafts is equal to the thickness of the weight disks  3 . 
         [0035]    By a selection of the rotational position of the outer sleeve  10  of the handle  4 , the pin devices  7  can be slid out stepwise so far that the projection  23  can come into engagement in any optional circumferential groove  20 . 
         [0036]    In that the pin locks  22  are non-rotational in relation to the housing means  5  and the projection  23  of the pin lock  22  extends down through the longitudinal groove  18  of the pin devices, the pin devices will also be rotationally locked in relation to the housing means. It should further be mentioned that the pin lock  22  is, by means of spring  24 , biased in that direction which is required for the projection  23  to snap down into a suitable circumferential groove  20  in the shaft  19 . 
         [0037]    In the foregoing, it was considered how the disk locking devices  8  are spring-biased radially outwards, i.e. towards their locking positions. This is realised in that the shaft  19  is spring-biased in an outward direction, i.e. towards the disk locking devices  8  and in that the shaft  19  has, at its outer end, a conical end portion  25  against which radially inner ends of the disk locking devices  8  abut. 
         [0038]    It will further be apparent from  FIG. 3  that the pin lock  22  has a lower operating portion  26  which, on placing of the dumbbell in the base unit  1 , lifts the pin lock  22  against the action of the spring  24  to an open position where the projection  23 , granted, prevents rotation of the pin devices  7  by engagement with the edges of the groove  18 , but nevertheless permits axial movements of the shaft  19 . Only when the dumbbell is lifted out of the base unit will the pin lock  22  move downwards and fall down, or snap down, in the circumferential groove  20  which corresponds to the selected projectional position of the pin devices  7 . 
         [0039]    In one alternative embodiment, the disk locking devices  8  are disposed fixed in the radial direction and the openings  6  are formed so that the disk locking devices, in a rotational position about the longitudinal axis of the pin devices  7 , are freely movable in the axial direction through the openings  6 , while, in another rotational position, they come into engagement with axially outwardly directed surface portions on the weight disks in order thereby to prevent these from falling away from the pin devices  7 . 
         [0040]    It will be apparent from the foregoing that if, for example, a base unit  1  is provided with two sets of weight disks and a handle  4 , with both of the pin devices  7  wholly retracted, is placed in the base unit, an optional number of weight disks  3  can be secured on the handle quite simply in that this is rotated a corresponding number of steps. When, thereafter, the dumbbell is lifted out of the base unit  1 , the selected number of weight disks is automatically locked on the dumbbell so that no weight disks can drop off. In the alternative embodiment, the weight disks are moreover rotationally fixed so that a relative rotation is prevented between the weight disks and the disk locking devices. 
         [0041]    If the number of weight disks on the dumbbell is to be changed, it is simply placed in the base unit, whereafter the handle is twisted through as many rotational steps as correspond to the desired change in the number of weight disks on the dumbbell. 
         [0042]    Above, it was described how the locking devices for locking the projectional positions of the pin devices and for locking the weight disks on the pin devices have an “automatic” function. However, it is possible to design the locking devices for manual operation either jointly or separately.