LOAD-CARRYING UNIT

Abstract: Carriage for a portable load-carrying unit (10), which is adjustable between an inoperative position and an operative load-carrying position, comprising gripping means (27), at least one pair of links (14) which are pivotally connected with each other in a common joint (15) at one end thereof, and at least one load-carrying wheel (17) rotatably mounted at said joint. The carriage of this invention is characterized in that said links (14) at the other ends are operatively connected to said gripping means (27) and are guided to be pressed towards each other by a lifting force applied to said lifting means to bias the carriage towards said operative position to lower the load-carrying wheel at said common joint (15) in order to transfer gradually the load carried by the lifting means, to said carriage.

Description: LOAD-CARRYING UNIT This invention relates to a carriage for a. portable load-carrying unit, which is adjustable between an in¬ operative position and an operative load-carrying posi¬ tion, comprising gripping means, at least one pair of links which are pivotally connected with each other in a common joint at one end thereof, and at least one load- -carrying wheel rotatably mounted at said joint. The invention will be described as applied to a combined handbag/shopping-troll ey. Thus, the state of the art includes the common shopping-trolley comprising a chassi equipped with wheels, on which a bag, suitcase, etc, typically of fabric or coated fabric, is mounted. The trolley has a pair of small wheels at one end of the chassi and a handle-frame at the opposite end there- of. The trolley is pulled at the handle-frame by one hand. The handle-frame may be telescoped or folded down to shorten the chassi so as to make possible to carry the shopping-trolley by gripping said shortened chassi. This type of shopping-trolley is practically the only one available but it has not been widely used. The outlook of the shopping-trolley usually appeals to older people only. Younger people, and some older people as well, who want to make a vigorous and youthful impres¬ sion hardly bring along such a shopping-trolley. Anyhow, this type of shopping-trolley has several drawbacks, which hardly promotes the popularity thereof. When the trolley is being pulled the pulling arm has to be twis¬ ted in a rather unnatural way, which is uncomfortable and tiring, and often the heel is hit by the wheels of the trolley during use. If the trolley has to be car¬ ried, e.g. to bring it on a bus or through a crowd of people, the wheels may make the user of the trolley dir¬ ty and this may happen to others as well. When the shopping-trolley is brought indoors the wheels thereof may soil the floor. OMPI -,-v. WIPO « It is true that a suitcase has been proposed having displaceable lifting means for co-operation with a pair of racks engaged by tooth-wheels transmitting a reversed movement to a second pair of racks equipped with load- -carrying wheels. However, this arrangement is not use¬ ful, as a heavy loaded suitcase would cause too much strain in the tooth-wheel and rack mechanism. When a load is being lifted with straight arms, it is not the lifting movement as such that is exhausting but rather the following continuous load on the fingers, arms and back. When lifting e.g. a suitcase with straight arms, the more powerful muscles of the legs may be used. Thus, it is most important that a reduction of the car¬ ried load is obtained in the lifted position to unload the fingers, arms and back. The primary purpose of this invention is to provide a combined bag/shopping-trolley eliminating said draw¬ backs, in which the load is partly relieved when the combined bag/shoppiπg-trolle-y is being carried in a lifted position. This is achieved by a carriage of the type initial¬ ly referred to, wherein said links at the other ends thereof are operatively connected to said lifting means and are guided to be pressed towards each other by a lifting force applied to said lifting means to bias the carriage towards said operative position for lowering the load-carrying wheel at said common joint in order to transfer gradually the load carried by the lifting means, to said carriage. The carriage of this invention may be used on suit¬ cases, picnic-cases, baby-lifts, golf-carriages , canoe- -carriages, barrow-carriag.es, and other portable load- -carrying units which can -be carried with straight arms. The accompanying drawings which are incorporated in and constitute a part of this specif cation, illustr- OMPI ™ ° ate several -embodiments of the invention and, together with the description, serve to explain the principles of the invention. FIG. 1 in the drawings is a diagrammatical per- spective view of a first embodiment of the car¬ riage of this invention carrying -a suitcase, FIG. 2 and 3 are diagrammatical side views of the carriage according to FIG. 1 in operative and in¬ operative positions, respectively, and show the geometry of the carriage, FIG. 4 and 5 are vector diagrams showing the com¬ ponent forces obtained in the positions according to FIG. 2 and FIG. 3 ,respectively , FIG. 6 is a diagrammatical side view of a second embodiment of the carriage, FIG. 7 shows diagrammatically one embodiment of a lifting handle for actuating the carriage, FIG. 8a is a diagrammatical side view of a third embodiment of the carriage, FIG. 8b is a diagrammatical end view of the load- -carrying unit shaped as a tray, e.g. for the em¬ bodiment shown in FIG. 8a, FIG. 9 -is a perspective view of two links carrying a wheel and forming part of the carriage of this invention, FIG. 10 is a diagrammatic side view of a fourth embodiment of the carriage, FIG. 11 is a diagrammatical side view of a fifth embodiment of the carriage of this invention equip- ped with braking means, FIG. 12 is a fragmentary side view of a first em¬ bodiment of the braking means used in the embodi¬ ment according to FIG. 11, FIG 13 is a fragmentary side view of the carriage, disclosing a second embodiment of the braking means -^URE OMPI So * £ for retarding the movement of the carriage when adjusted from the operative load-carrying position to the inoperative position, and FIGS. 14a and 14b show two kinds of wheel -braking devices arranged at the carriage of this invention. Referring now to. FIG. 1 it is shown therein a first embodiment of the carriage according " to the teachings of the invention, comprising a rigid rectangular plate 10 which can be provided as the load-carrying base-plate of a case diagram atically shown with dash and dot lines 11. This case may be made of fabric, coated fab¬ ric or some other soft material , but it may also be made of a more or less rigid material , e.g. glass fi¬ ber reinforced plastics. A skirt 12, diagrammatically shown with dash and dot lines, extends below the plate 10 and should be of a rigid construction, which, as will be described below, can be used. as a support for the case in a parking position thereof, wherein the case is not supported by the -wheels. However, the skirt may be replaced by one or more supports of some other kind. Regarding the case proper the designer may design the case in a fashion which he considers the best one from an esthetical and/or useful point of view. Two pairs of aligned guides 13 are arranged on the bottom side of the plate 10 one at each of the longi¬ tudinal edges of the plate. At each side of the plate, two links 14 are pivotally connected to each other in a common joint by means of a shaft 16 interconnecting the links at opposite sides of the plate two wheels 17 being rotatably mounted to said shaft. At their opposite ends the two links at each side are pivotally connected to the plate 10 at joints 18 for pivotal movement about transverse axes said joints linearly being displaced along said guides 13. At the.centre of the edge of the plate a joint 19 for another pair of links 20 is ar- _ OMPI ranged which are pivotally connected to said first pair of links 14 at joints 21 spaced from joint 15 a distance equal to the length of each link 20. The links 20 are pivoted for movement about transversally extending axes at said joints. Spring means 22 is arranged to hold the carriage towards the bottom side of the plate when the load on the load-carrying unit 10 is below a predeter¬ mined magnitude. The geometry of the carriage will now be explained with reference to FIGS. 2 and 3. Ropes or strings 23 are attached to the joints 18 of the carriage (one rope only being shown in the drawing) and these ropes are extended towards the joints 19, passing through guides 24, and from there upwards to guides 25 and then towards the centre of the upper wall of the case, and finally through further guides 26 to a handle 27 which is dis- placeable relative to the case 11. Thus, when the handle 27 is being lifted the joints 18 will be pressed towards each other according to FIG. 2, or to an operative position, wherein the wheels are further projected from the lower side of the plate 10. When the hold on the handle is released the carriage will be withdrawn towards the lower side of the plate 10 under the bias of spring means 22 to the inoperative position shown in FIG. 3. The position of the wheels thus will be dependent on the pulling force exerted on the ropes 23, i.e. the force applied to the handle 27. Provided that the load-carrying unit is sufficiently loaded, the wheels will be projected from the lower side of the case when the handle is lifted, to a degree that depends on the displacement of the handle 27, a greater portion of the total weight being transferred to the wheels 17. This distribution of the weight is shown by the vector diagram according to FIG. 4 which shows the force R in the link 14 resulting from a verti- cal component force p1 and a horizontal component force p2, i.e. the pulling force acting on the rope 23. In this position, which corresponds to FIG. 2, the com¬ ponent forces p1 and p2 are approximately of the same magnitude. When the handle 27 is further lifted the com¬ ponent force p1 will be greater than the component force p2 the wheels being further projected. If the handle 27 is being lowered, the component force p2 becomes grea¬ ter than the component force pi as shown in FIG. 5, i.e. the wheels are displaced towards the plate 10. If the handle 27 is completely released, i.e. the case is put down onto the support, the carriage will be brought to its inoperative position inside the skirt 12. Thus, the case is supported by the skirt as mentioned above. The handle may easily be arranged in such a way that it can be gripped and held in the same manner as a common case handle, also when the shopping-trolley is supported by the carriage. This handle may be combined with a second handle attached directly to the case 11, which means that the combined bag/shopping-trolley may be carried as an ordinary bag if loaded or not. Thus,- the carriage will be kept in the inoperative position. The operation of the joints 18 may be accomplished by the transmission between the handle and the joints, which is shown in FIG. 6 and. s constructively simpler than the first mentioned transmission. A major part of the transmission may form a completely enclosed unit with a base-plate or tray 10. In this embodiment the base¬ plate 10 is provided with a pair of upwardly extending side walls 28 which may form part of a frame which may form the above- entio'ned skirt 12. In each of these side walls the two links 14 are displaceably guided at the joints 18 thereof in guiding slots 13' correspond¬ ing to the guides 13 in the base-plate 10 according to the embodiment shown in FIG. 1. Along the centre line of the side wall a third guide-slot 29 is arranged, in which a member 30 is displaceably guided, said member being connected to the centre of rope 31, the two ends of which are connected one to each joint 18. Instead of using one rope, two links or spring means may be ar¬ ranged between the member 30 and the displaceable joints 18. By the use of a -resilient rope or string 31 resi¬ liency is achieved between t-he handle 27 and the load- * -carrying carriage, a gradually increasing resistance against the lifting of the handle 27 being obtained thereby. The ropes 23, and rope or link 23' , respectively, may in part be replaced by a displaceably guided yoke forming an integral part. of the handle 27. On the whole the connection between the joint 18 and the handle 27 has to be adapted to the design and the nature of the bag or case known arrangements for transmitting mecha¬ nically a movement from one part to another being app¬ lied in order to achieve the desired unloading of the lifting handle. In FIG. 7 a handle 27' of special design is shown which allows lifting without the carriage being adjus¬ ted towards the operative position thereof. Since the handle 27' is pivotally connected to the portable load- -carrying unit at 40a (40b) and has a predetermined length, it is possible to grip the handle at a selected position along the portion b in order to control the magnitude of load transferred from the handle to the carriage. If lifted at the portion b* the handle 27' effects the greatest possible transmission of load to the carriage, while the handle if .gripped at the por¬ tion b" effects no load transfer at all to the carriage. In a load-carrying unit provided with a carriage accord¬ ing to this invention and " provided with a handle accord- ing to FIG. 1 _ the carriage can be brought to an inope- _ OMPI rative position by adjusting the grip around the handle 27* to a position closer to the joint 40a. Portions a-c of the handle can form a rigid construction to fully eli¬ minate the tendency of twisting of portion b of the handle this may be provided with an additional rigid portion d, joint 40a being replaced by a joint 40b at said rigid portion. H-owever, the portion b of the handle may be resilient, and in the alternative embpdiment of the handle with portion d and joint 40b portions a-c may be resilient. At least one rope 23" at each side is attached to the handle at 41, said rope being guided by guides 42a and 42b. When the handle 27" is pivoted at joint 40a or 40b joints 18 of the carriage are pressed together as described above. The handle just described may be operatively con¬ nected via transmitting ropes or links to the carriages described above or to further carriages to be described be! ow. Thus, according to the present invention a carriage is provided which can be co b-ined with or form an inte¬ gral part of an ordinary bag or case the design of which does not differ substantially from the design of an o»— dinary bag or case. Only when there is a need of unloading the weight of the case from the handle 27, the carriage will be ad¬ justed to an operative position and this is effected by properly grabbing and lifting the handle. The load which has to be carried at the handle is dependent on the geo¬ metry of the carriage and of the displacement of the handle and the associated projection of the wheels. How¬ ever, it is advantageous if the load carried at the handle could be independent of the displacement of the handle, i.e. the load at the handle should be a prede¬ termined percentage of the total load independently of the displacement of the handle within certain limits. This is desirable considering the bag, case, trolley or carriage may be used by persons of different heights. The carriage being in the operative position thereof, the bag will be positioned beside the body of .the user and at a level which is below the level of a common bag carried in the conventional way. Thus, the carriage will automatically be adjusted to an operative position at a level which is perfect for each person carrying the case independently of the height of such person. The position for carrying and using such a carriage will be most convenient. When the carriage is put down or lifted at a further handle attached to the case proper in a conventional way, the carriage will be in an in¬ operative position and the wheels will be protected in- side the outline of the case. Accordingly, the risk .of soiling from the wheels is eliminated when the carriage is handled in this way. A third embodiment of the carriage is shown in FIG. 8a. The base-plate 10 shown in the previous embodi- ments has been replaced by a " base-tray 10' with a cen¬ tral wheel-receiving recess 31. In this embodiment one - wheel 17 only is used which is located centrally within the recess 31 of the base-tray 10'. The carriage is ad¬ justed to the operative load-carrying position according to this embodiment by using a mechanism without guiding slots, by means of which a substantially constant per¬ centage of the total load is transmitted to the wheel by lifting the handle and thus adjusting the carriage to the operative position thereof. When the handle 27 is being lifted, the adjustment of the carriage according to FIG. 8 to the operative position will be initiated provided that the load on the base-tray 10' which is attached to the carriage by links 32 is sufficient to overcome the force of the spring means 22. Said force will gradually increase during adjustment of the car- riage to the operative position. Also the transmission ratio between the upward movement of the handle 27 and the upward movement of the base-tray 10' increases gra¬ dually. By proper choice of the spring rate of said spring means 22 and the dimensioning of the carriage the load carried at the handle 22 may be substantially constant during adjustment of the carriage to the ope- . rative position. The movement of the wheel during ad¬ justment of the carriage to the operative position may be effected by lifting the handle 27 a distance of about 40 cm. Thus, the handle may be lifted from a le¬ vel spaced 50 cm from the support to a position at a level spaced about 90 cm from the support. However, it is possible to use an extended lifting movement of the handle for adjusting the carriage to the operative position thereof. In certain applications of this in¬ vention, the adjustment of the handle may comprise a distance of 100 cm. An end view of the base-tray 10' is shown in FIG. 8b. Reinforcing profiles 33; 34 are used for the con¬ nection of the carriage to the load-carrying unit. Thus, links 32 are attached to the profile 34, and the profile 33 is, used for guiding the pairs of links 14 and 20. In FIG. 9 two of the links 14 constituting part of the carriage, are shown. Instead of using rigid links 32 interconnecting the carriage and the load-carrying base-tray 10' resilient elements may be used. When re¬ silient elements are used the load-carrying base-tray is resiliency suspended on the carriage and the pro¬ jection of the wheel 17 can be somewhat greater as the resilient elements 32 do not suddenly stop the adjust¬ ment " of " the carriage to the extreme operative position thereof. A fourth embodiment of the carriage of this in- 1 1 vention is shown in FIG. 10. Slots are used to guide the joints interconnecting the links 14 and 20. A tray- -shaped load-carrying unit 10" is used in this embodi¬ ment, in which unit the horizontal guiding of the joint 18 takes place in slots 35 arranged in the unit. These slots 35 are used for operatively connecting the load- -carrying unit 10 arrd the carriage of the invention. An accurate centering of the wh-eel 17 within the recess 31 is automatically obtained by using two spring means 22'. A fifth preferred embodiment of the carriage of this invention is shown in FIG. 11, wherein details cor¬ responding to details of the embodiments previously de¬ scribed have been given the same references with 100 added. This embodiment is in some respects similar to the embodiment according to FIG. 10, but the spring means 22 have been omitted. In this embodiment of the carriage, a slide mechanism 43 is shown, which further reduces the necessary lifting force at the handle 127 when the carriage is in the operative position thereof. The mechanism 43 is so arranged that there is a small resistance against adjustment of the carriage to the operative position but a substantially greater resis¬ tance against adjustment of the carriage to the inope¬ rative position thereof. This effect of mechanism 43 is obtained in a way to be described below. The pairs of links 120 which are positioned one pair at each side of the load-carrying unit 110 are attached, at the up¬ per end thereof, to a lower cross piece 44 of the slide mechanism, guided by two rails 45 and 46. Two vertical links 47 and 48 are connected between the handle 127 and the cross piece 44. The upper ends of the rails 45 and 46 are connec¬ ted to a rigid cross-bar 49 the two vertical links 47 and 48 being disposed on the inner side of bar 49. Fric- tion means 51 formed by an angled plate having two re- cesses, each of which receives one of .the rails 45 and 46, respectively, is connected to the cross piece 44 by flexible means 50 - see FIG. 12. When the handle 127 is being lifted the cross piece 44 is pulled upwards by the two vertical links 47 and 48, guided by the rails 45 and 46. At the same time said rails will be moved upwards in relation to the support during adjustment of the carriage to the operative position thereof. However, this move¬ ment of the rails will be slower than the movement of the cross piece 44. Thus, the flexible means 50 will pro¬ vide a tilting of the friction means 51 so that said means 51 at low friction will be guided upwards along the rails 45 and 46. However, during movement in the opposite direction, i.e. when the handle 127 is released, the vertical links 47 and 48 and the cross piece 44, the flexible means 50, fixedly attached to the cross piece 44, will effect tilting of the friction means 51 in the opposite direction, whereby the two edge portions of each of the two recesses therein will more firmly en- gage the two rails 45 and 46. on each side thereof. Thus, the friction forces will be increased and the displace¬ ment in this direction will be slowed down. The mecha¬ nism 43 exerts a certain resistance to the adjustment of the carriage to the inoperative position* which means that the load carried at the handle 127 can be further decreased. The resistance against adjustment of the car¬ riage to the inoperative position can be arranged to gradually increase by resiliently connecting the upper ends of the links 120 to the cross piece 44, provided that said flexible means 5Q is fixedly attached to said upper ends of the links 120. A force directed downwards on said flexible means 50 will in this case be dependent on the load in the load-carrying unit 110 in such a way, that an increasing load will exert a more efficient jamming between the edge portions of the two recesses OMP 1 3 of said friction means 51 , the downward movement of said rails 45 and 46 thus being braked. By such an ar¬ rangement said jamming between the recesses of friction means 51 and the rails 45 and 46 will be substantially eliminated when said slide mechanism 43 and the rails 45 and 46 are moving upwards by the handle 127 being lifted.. Another embodiment of the braking mechanism is al¬ so shown in FIG. 11, which mechanism may be used sepa- rately or together with the mechanism 43. ' The joint 118 connecting the two pairs of links 114 and 120 is guided in the slot 135 by rollers 52 rotatably mounted at said joint. Several recesses 53 provided in the upper side of said slot are defined each by a bottom surface which has a steeper slope at the outer end of the recess than at the inner end thereof. The rollers and the recesses permit a further unloading of the handle 127. This can be explained by the fact that movement of the rollers 52, when moving outwards in the slot 135 at adjustment of the carriage to the inoperative position, will be effectively braked by the interengagement of the rollers and the recesses 53. This braking effect may be made more or less significant by proper dimensioning of the depth of the recesses 53 and by proper choice of the angle at which each recess opens in slot 135. Thus, it can be advantageous to give the recesses 53 different shapes, i.e. the recesses adjacent the ends of the slot are made deeper and/or are given, a steeper angle than the recesses remote from the ends considering that the horizontal component force -acting on the roller 52 will be increased when the rollers are moved outwards in the slot 135. When the rollers 52 have reached their outer¬ most- pos tion in the slot 135, i.e. when the wheel 117 carries no load and the load-carrying unit 110 is placed directly on the support, simple spring clips may be ar- OMPI 14 ranged at each end of the slot 135, the rollers 52 be¬ ing engaged with said clips prior to unloading of the wheel 117. Thus, said spring clips, preferably arranged to contact both the upper and the lower side of the rol¬ lers, may further displace the rollers 52 outwards, whereby the " wheel 117 will be completely retracted from the support. These spring clips may keep the carriage in the inoperative position also when a lifting force is applied to the handle 127 as long as the load in the load-carrying unit 110 is not sufficient to overcome the retaining force applied to the rollers 52 by the spring clips. It is possible to release the rollers from the spring clips by jerking the handle 127. These spring clips may be used in the other embodi¬ ments of the carriage of this invention as well. The spring clips are independent of the braking mechanism used to further decrease the load at the handle when the carriage is in the operative position. In FIG. 13 a second embodiment of the braking mecha¬ nism, replacing mechanism 43, is shown. This mechanism forms part of the carriage operating means shown in FIG. 11 and may replace the members 50 and 51. However, in this embodiment the vertical links 47 and 48 must be located on the outside of the cross-bar 49. On the ' inside of each link a set of projecting ribs or beads 54 is provided to co-operate with at least one rib or bead 55 at the outer side of each cross-bar 49. Preferably, the projecting ribs or beads 54 form an integral element which may be of plastics arid is attached to the inner side of each link. The rib or bead 55 may be formed by the cross-bar 49, but preferably it is arranged in a separate element which is attached to the outer side of the cross-bar. There may be one or more ribs or beads 55 arranged on one and same element. The braking mechanism O /». WI 1 5 of this embodiment provides a gradually increasing brak¬ ing effect when the load at the handle increases. This gradually increasing braking effect can be explained by the fact that the bearing force between the projecting ribs or beads. 54 and the projecting ribs or beads 55 will increase with increasing load on the load-carrying unit. This increasing bearing force will be obtained by a transverse force applied to the vertical links 47 and 48 when the handle 127 is being lifted. Thus, there is another set of vertical links - not shown in the draw¬ ing - on the other side of the load-carrying unit 110, which means that these links will bear against a cross- -bar 49 arranged on said other side of the load-carrying unit, when the handle 127 attached to the two sets of vertical links, is being lifted. Although there is a great pressure between the ribs or beads 54 and the ribs or beads 55, the vertical links may be moved up¬ wards over the ribs or beads 55 forming a sloping sur- face 56 at the lower side thereof. Thus, the ribs or beads 54 will slide over said sloping surface 56 on the rib or bead 55 when the vertical links are displaced in relation to the cross-bar.49. Of course, it is possible that two or more ribs or beads 54 on each vertical link co-operate with a corresponding member of ribs or beads 55 on the cross-bar in order to reduce the wear and/orto increase the braking effect of the mechanism when the carriage is adjusted to the inoperative position. When the handle is released the pressure between the ribs or beads 54 and 55 will be reduced, since the transverse force on the vertical links will be reduced. Although a handbag is equipped with a carriage of this- invention which makes, it substantially easier to carry a heavy load, it may nevertheless be necessary for the user of the wheel-carried bag to stop and rest, e.g. when bringing the bag uphill. By arranging braking means behind the wheel or the wheels 17 of the carriage, this recovery may be achieved without the necessity of plac¬ ing the bag on the ground and without the necessity of exerting a force onto the handle preventing a backward movement of the bag. In FIGS. 14a and 14b two different types of such braking means co-operating with the car¬ riage of this invention are shown. In FIG. 14a this braking means comprises a simple rubber pendulum 36 attached to one of the links 14. This pendulum 36 may contact the ground when the wheel 17 is in its lowered position. Thus, an initial movement backwards will bring the pendulum 36 to engage between the wheel 17 and the support, thereby preventing a further backward movement. An alternative embodiment of the braking means of the carriage of this invention is shown in FIG. 14b. In this embodiment a braking roller 37 is resiliently suspended behind the wheels from the link 14 and from the centre of the wheels by resilient means 38 and 39, respectively. The operation of this braking means cor¬ responds to the operation of the braking means accord¬ ing to FIG. 14a, i.e. at an initial movement backwards of the wheel 17 the roller 37 will slip into engage¬ ment between the wheel 17 and the support. It will be apparent to those skilled in the art that various other modifications and variations in addition to those mentioned above could be made in the carriage of the invention without departing from the scope and spirit of the invention. Thus, the carriage may be used together with especially designed carry¬ ing means, e.g. for moving water-cans, tool-bags, port¬ able f re-extinguishers, gardening hampers, bottle-ca¬ ses, etc. OMP ^

Claims: CLAIMS 1. A carriage for a portable load-carrying unit (10;110), which is adjustable between an inoperative position and an operative load-carrying position, com- prising gripping means (27), at least one pair of links (14;114) which are pivotally connected with each other in a common joint (15;115) at one end thereof, and at least one load-carrying wheel " (17;117) rotatably moun¬ ted at said joint, c h a r a c t e r i z e d in that said links (14;114) at the other ends are operatively connected to said gripping means (27; 127) and are gui¬ ded to be pressed towards each other by a lifting force applied to said lifting means to bias the carriage to¬ wards said operative position to lower the load-carry- ing wheel at said common joint (15;115) in order to transfer gradually the load carried by the lifting means, to said carriage. 2. A carriage according to claim ^ c a r a c ¬ e r i z e d in that the proportion of the total load, carried by the wheel (17;117).of the carriage is depen¬ dent on the displacement of the gripping means (27; 127) . 3. A carriage according to claim 1 or 2, c h a - r a c t e r i z e d in that the load-carrying unit (10; 110) forms the bottom of a bag or case (11). 4. A carriage according to claim 3, c h a r a c ¬ t e i z e d in that said gripping means is guided in the upper side of the bag or case. 5. A carriage according to claim 3 or 4, c h a - r a c t e r i z e d in that said gripping means (27') comprises a rigid extended element (b;d) pivotally at¬ tached to the bag or case. 6. A carriage according to any of the preceding claimSj c h a a c t e r i z e d in that the load-car¬ rying unit (10;110) has the shape of a tray forming a wheel-receiving recess (31). OMPI 7. A carriage according to any of the preceding claims, c h a r a c t e r i z e d by spring means (22) biasing the pair of links (14;114) for complete withdrawal of the load-carrying wheel from the opera¬ tive position. 8. A carriage according to any of the preceding claims, c h a r a c t e i z e d in that wheel braking . means (36;37) is attached to the carriage. 9. A carriage according to any of the preceding claims, c h a r a c t e r i z e d in that braking means (43;52, 53;55, 56) for the gripping means is operative- ly connected between said gripping means (27;127) and the pair of links (14;114) carrying the wheel (17;117), said braking means (43) being so arranged and construc¬ ted that a small resistance is exerted against adjust¬ ment of the carriage to the operating position thereof, and a substantially greater resistance is exerted against the adjustment of the carriage to the inoperative posi¬ tion thereof. OM ^JWA

Inventors: WESSMAN O
Applicants: WESSMAN DEV AB OLLE, WESSMAN O, OLLE WESSMAN DEV AB
Application year: 1980
Main classification: B62B1
IPC codes: A45C5, B62B1