A LIFT FOR VEHICLES, E.G. VANS AND VEHICLES FOR THE DISABLED

Abstract: An object of the invention is to provide a lift which does not obstruct general boarding of and disembarking from the vehicle, including when the lift is not in use. The novel and characterizing aspect of the lift according to the invnetion is that the lift comprises at least two swing arms (8) which are mounted at the vehicle bottom (10), said swing arms being connected with lifting arms (14) which are mounted on the platform (16), wherein the movements of the swing arms are synchronized and swing with opposite directions of rotation, and wherein the mount of the lifting arms comprises the feature that the mount of the rear end (14.2) of the lifting arms comprises at least a mount which at least allows displacement, and that the mount of the front end (14.1) of the lifting arms at least comprises a mount which at least allows rotation about at least an axis. When the swing arms are mounted at the vehicle bottom, it is ensured that, when the lift is not in use, the platform may be clear of doors or the like which are access paths to and from the vehicle. Moreover, the drive unit may be stowed away under the vehicle, if desired. When the movements of the swing arms are synchronized and swing with opposite directions of rotation, it is ensured that the movements of the swing arms obtain a common vertical component which is utilized for raising and lowering the platform.

Description: A lift for vehicles, e.g. vans and vehicles for the disabled A lift for mounting at the bottom of a vehicle of the type which comprises a platform connected with lifting arms, said lifting arms being in connection with a drive unit which can impart a raising movement and a lowering movement, respectively, to the lift. It is generally known to have a hydraulic/electrical lift mounted at the rear on trucks and other vehicles; some models are intended for mounting inside the vehicle. The last-mentioned type is particularly intended for use in vehicles for the disabled. This type requires space and also blocks the door opening concerned. All the mentioned types of lifts have the property that in their folded-together state they block the access to the vehicle at the opening at which the lift is mounted. It is known from US 5,118,246 that types of lifts have been developed which can be folded together and stored under the vehicle. This gives access to the vehicle, also without the use of the lift. Further, lifts intended for mounting on vehicles for the disabled are known from US 5,253,973 and PCT/US94/04184. These known types of lifts, however, have the drawback that they are all mechanically complicated, with hydraulics, etc, and require a relatively great intervention in the vehicle and/or require relatively much space under the vehicle. Accordingly, these types are not very universally useful, including e.g. not for mounting under smaller vans, minibuses, smaller vehicles for the disabled or the like. An object of the invention is to provide a lift which does not interfere with general boarding of and disembarking from the vehicle, including when the lift is not in use. Another object is to provide a lift which is more compact than the known types, allowing it to be used for the greatest possible number of types of vehicles, including vehicles with limited space. Another object is to provide a lift which is easy to use, requires little space for use, and which can be mounted under a vehicle without significant intervention. Still another object is to provide a lift which is simple, and which has low manufacturing costs . The novel and characterizing aspect of the lift according to the invention is that the lift comprises at least two swing arms which are mounted at the vehicle bottom, said swing arms being connected with lifting arms which are mounted on the platform, wherein the movements of the swing arms are synchronized and swing with opposite directions of rotation, and wherein the mount of the lifting arms comprises the feature that the mount of the rear end of the lifting arms comprises at least a mount which at least allows displacement, and that the mount of the front end of the lifting arms comprises at least a mount which at least allows rotation about at least an axis. When the swing arms are mounted at the vehicle bottom, it is ensured that the platform, when the lift is not in use, may be clear of doors or the like, which are access paths to and from the vehicle. Further, the drive unit may be stowed away under the vehicle, if so desired. When the movements of the swing arms are synchronized and swing with opposite directions of rotation, it is ensured that the movements of the swing arms obtain a common vertical component which is utilized for raising and lowering the platform. The mount of the lifting arms and the connection between the swing arms and the lifting arms enables conversion of the rotary movements of the swing arms into a displacement of the platform. Moreover, the swing arms need only be clear of the vehicle in order to be able to swing. The axis of rotation may be perpendicular to the end or the side of the vehicle, so that there is no need for any outward movements relative to the vehicle, whereby no extra free space is needed around the vehicle when the lift is to be used. Such a lift contains few components and may be manufactured at low costs . In addition, the lift may be constructed so that it may be bolted to the vehicle in a simple manner, which may take place without significant intervention. The mount of the front end of the lifting arms may comprise at least a mount which allows displacement in at least one direction, whereby lifting arms and swing arms may be firmly connected. This gives a particularly simple embodiment . Alternatively, the swing arms may be connected with the lifting arms via linkages, and the platform may be divisible into at least two parts which may be rotated in the linkages. This ensures that the parts of the platform may be swung away when the lift is not in use, including inwards under the vehicle, which gives particularly good access paths to the vehicle. The linkages may be connected with means for power transfer ensuring that the lifting arms and the parts of the platform rotate about substantially vertical axes . This provides a lift which can readily be stowed at the two platform parts, be swung around and inwards under the vehicle in the transport position of the vehicle. At the same time the platform parts are protected from tilting downwards, which is of great psychological importance to the users . The platform may be provided with locking means for coupling the parts of the platform together, so that these may be retained in a specific e.g. assembled position, e.g. for reasons of safety. Moreover, the lift may be provided with locking means ensuring that the platform does not unintentionally leave its travelling position, which might have disastrous consequences in the traffic. The swing arms may comprise threads having a pitch which allows rotation of the swing arms and thereby raising or lowering of the platform by means of at least a nut, which is moved axially to and fro on the threaded part of the swing arms. This ensures that the power for raising and lowering the platform may be supplied translatorily and may thereby be exerted by e.g. a linear actuator. The nut may advantageously comprise threaded holes having right-handed threads and left-handed threads, respectively, so that the same nut may cooperate with both swing arms at the same time. This also saves a guide for the nut, since the nut can absorb a moment of force in cooperation with the swing arms. The swing arms may furthermore be connected with a gear which comprises a plurality of toothed wheels and at least a rack, which gives another expedient embodiment where the power for raising and lowering the platform may be supplied translatorily. The lift may be driven by an electrically, pneumatically, hydraulically or manually driven actuator. Generally, it must be expected that the possibility of using electricity, and thereby also pneumatics and hydraulics, is present on vehicles . Manual operation may be needed in other conceivable situations, where the option of electrical or mechanical connection is perhaps not available. The lift may comprise a hinged plate, which creates contact between platform and internal vehicle bottom in the working position, and which shields the swing arms at least partly in connection with the movement of the platform. This provides a simple shield, which simultaneously bridges the platform and the internal vehicle bottom so that e.g. the wheel from a wheel chair cannot "drop through". The platform may comprise at least two sections, of which at least one section is extensible and retractable, thereby making the lift particularly compact when it is not in use. Power for extending and retracting the at least one section may be applied by means of at least one scissors device or at least one rack device or at least one wire pulling device or at least one spindle device in expedient embodiments . The lift may comprise a control unit, by means of which control unit at least one function may be operated, and which is hand-held and wireless in one embodiment. This solution provides the possibility of operating the lift with an optimum degree of freedom with respect to where the user is relative to the lift and the vehicle. Finally, the lift may be equipped with a built-in trailer coupling, which allows driving with a trailer or the like without further mounting of equipment. Typically, a traditional trailer coupling cannot be mounted on the ve- hide when a lift has been mounted. The invention will be described below with reference to the drawings, which show examples of embodiments of the invention, and in which: Fig. 1 is a lateral view of an embodiment of the lift according to the invention, where the lift is in an upper position and the platform is level with the vehicle bottom. Fig. 2 shows the same as fig. 1, but seen inwards toward the end of the vehicle. Fig. 3 is a top view of the lift in a folded-together state, also called travelling position. Fig. 4 shows the nut and threads on the swing arm. Fig. 5 shows a threaded part on swing arms with nut and actuator. Fig. 6 is a detailed view of an embodiment of a connecting link between a swing arm, a lifting arm and a horizontal connecting rod. Fig. 7 is a drawing of a lift mounted on a vehicle, where the lift is in the lower position. Fig. 8 shows the same as fig. 7, but with the lift in the central position. Fig. 9 shows an embodiment of a lift. Fig. 10 shows a lift with a scissors device. Fig. 11 shows a retracted lift. Fig. 12 shows another embodiment of a lift. Fig. 13 shows a section A-A of a gear. Fig. 14 shows a section B-B of a gear. Fig. 1 shows an embodiment of the lift according to the invention. The lift is mounted under the vehicle 10 so that it may be used at the rear end of the vehicle. The lift is in an upper position, and the platform 16 is level with the internal vehicle bottom 32. Swing arms 8 are visible under the vehicle, having threads 24, a nut 26 for rotating the swing arms 8, and an actuator 6 pressing or pulling the nut 26 along a threaded part 24 of the swing arm. When the platform 16 is lifted, contact is created between the platform 16 and the internal ve- hide bottom 32 by using a hinged plate 30. In this embodiment, the plate 30 is secured on the platform 16 and may be folded down to cover the gap between the platform 16 and the internal vehicle bottom 32. Of course, other types of plates may be used, which are optionally mounted on the vehicle, if this might be advantageous. Fig. 2 shows substantially the same as fig. 1, but here seen inwards toward the end of the vehicle 4. This figure shows the swing arms 8 which are mounted at the vehicle bottom. The platform 16 comprises platform parts 18 between which locking means 22 are provided, said locking means ensuring that the platform parts 18 are kept to- gether. The locking means 22 moreover have the function that they contribute to imparting stability to the lift. Fig. 3 shows a vehicle 4 having a lift mounted thereon. The vehicle 4 and the lift are seen from above. The lift is in a folded-together state, also called travelling position. When the lift is in the travelling position, the platform parts 18 are rotated inwards under the vehicle bottom 10 and securely fixed. Each platform part 18 is rotated by means of a linkage 12 about a vertical axis. In a preferred embodiment, the linkages 12 are constructed as cardan joints which provide a connection between swing arms 8 and lifting arms 14, and which are moreover connected with a telescopic connecting rod 20. The connecting rod 20 is necessary in order to prevent the platform 16 from being unstable in a non-locked state. This is taken to mean that it is necessary to have means 20 which can transfer power/moment between the linkages 12. This is necessary since without these means 20 the platform 16 would merely tilt down when the lock 22 is opened. Two circular arcs are indicated in fig. 3 by dashed lines showing the path traversed by the platform parts 18 when they caused to assume a travelling position and a working position, respectively. Fig. 4 shows a section of the lift where the nut 26 and the threads 24 on the swing arms 8 are visible. When the nut 26 is pressed along the threaded parts 24 by means of an actuator 6, the swing arms 8 are forced to rotate, and thereby the platform 16 of the lift is lifted by the lifting arms 14 via the swing arms 8. The pitch of the threads is relatively low, and the nut 26 is therefore self-locking. The swing arms 8 with threaded parts 24 may be mounted under the vehicle 4 and will normally be en- capsulated by a cover 38 to protect the mechanism against dirt and corrosion. The swing arms 8 may be made in an angular member, or they may be made as shown in fig. 4, where the threaded part 24 is joined with the external part of the swing arm 8 immediately outside the protect- ing cover 38. The actuator 6 is arranged in the cover 38 or in extension of it, as is shown in fig. 5. This figure shows a threaded part 24 on swing arms 8, a nut 26 and an actua- tor 6, as it may appear in an embodiment. Everything is mounted in an assembled unit ready for mounting. Fig. 6 is a detailed view of an embodiment of a connecting link 12 between a swing arm 8, a lifting arm 14 and a connecting rod 20. The connecting rod 20 serves to ensure that the connecting link 12 is kept e.g. vertical, and that the two parts 18 of the platform are thereby kept in a horizontal position. Fig. 7 shows the rear end of a vehicle 4 equipped with a lift according to the invention, where the lift is in the lower position. The figure shows the two platform parts 18 of the lift, each having a plate 30 of its own. Also shown are swing arms 8 connected with lifting arms 14 via linkages 12. A telescopic connecting rod 20 is visible between the two linkages 12. The front ends 14.1 of the lifting arms 14 are mounted at the front edge 40 of the platform, and the rear ends 14.2 of the lifting arms are mounted at the rear edge 42 of the platform. The mount of the rear ends 14.2 is shown as a guide 28. Fig. 8, like fig. 7, shows the rear end of a vehicle equipped with a lift, but here with the lift in a central position. Fig. 9 shows a lift where power is transferred via a gear 54 from an actuator 6 to the swing arms 8 and from there to the lifting arms 14. The platform 16 is shown in the figure without a cover plate. In the view shown, the swing arms 8 and the lifting arms 14 are firmly connected. When the swing arms 8 rotate, the distance between the lifting arms 14 is changed, and this displacement is guided in that the front ends 14.1 of the lifting arms are mounted in a slide bearing 28.2 and the rear ends 14.2 are mounted in slide bearings 28.1. To keep the platform 16 centered, the lift is provided with a tilting rod device 52. In the embodiment shown, the platform 16 is constructed telescopically, so that there is a fixedly positioned section 44 as well as two extensible and retractable sections 45 and 46. These are extended by means of a wire pulling device 50 which pulls/pushes the outer section 46 which when being extended extends the section 45 by means of rods 48. The rods 48 are passed through holes in the section 45 and are provided with stop blocks on the rear side. Upon retraction, the sections 45 and 46 may thus be pushed completely together, as the rods 48 may freely move in the holes in the section 45. The lift may be provided with a motorized device for driving the wire pulling device 50, or it may be operated manually. The plate 30 is shown in a vertical position, where it thus shields the swings arms 8 e.g. for reasons of safety. With the platform 16 in an upper position, the plate 30 may be tilted down and serve as a bridge connection. Fig. 10 shows a lift which is likewise telescopic, and where the telescopic movement of the sections take place by means of scissors devices 56 which may be driven e.g. by an actuator 58. The actuator 58 is connected with the scissors devices 56 by means of a transverse rod 60. When the platform is telescopic, the platform need not be stowed away under the vehicle, but may instead be used as a footboard without obstructing the access paths to the vehicle. Fig. 11 shows a telescopic lift in a retracted state, where the plate 30 serves as a cover. The lift moreover comprises a rubber edge 62 which serves as a ramp for wheel chairs, as a kick edge and as a cushion against the base . Fig. 12 shows a telescopic lift where the parts 64 used for the telescopic movement extend inwards under the vehicle when the platform is in a retracted state. In this case, the lift must comprise a protective device ensuring that the platform cannot be raised unless the platform is fully extended. Fig. 13 shows a vertical section of an embodiment of a gear 54, where an actuator 6 is connected with a chain wheel 70 having a chain 66 which is guided by a chain wheel 68. The parts are incorporated in a box 72 which may be provided with bolt holes for mounting on the vehicle. The figure moreover shows swing arms 8. Fig. 14 shows a horizontal section in a gear 54. An actuator 6 is connected with a chain wheel 70 by means of a chain 66 which is supported by a chain wheel 68. the chain wheel 70 is connected via a shaft 78 with two bevel pinions 74 which are engaged with a crown wheel 76, said crown wheel 76 being connected with swing arms 8. Power and moment may be applied to the swing arms 8 in many ways, and the figures just present examples of possible embodiments.

Claims: Patent Claims 1. A lift for mounting at the bottom of a vehicle of the type which comprises a platform connected via lifting arms with a drive unit which can impart a raising movement and a lowering movement, respectively, to the lift, characterized in that the lift comprises at least two swing arms (8) which are mounted at the vehicle bottom (10) , said swing arms (8) being connected with lifting arms (14) which are mounted on the platform (16) , wherein the movements of the swing arms (8) are synchronized and swing with opposite directions of rotation, and wherein the mount of the lifting arms (14) comprises the feature that the mount of the rear end (14.2) of the lifting arms comprises a least a mount which at least allows displacement, and that the mount of the front end (14.1) of the lifting arms comprises at least a mount which at least allows rotation about at least an axis. 2. A lift according to claim 1, characterized in that the mount of the front end (14.1) of the lifting arms comprises at least a mount which allows displacement in at least one direction. 3. A lift according to claim 1, characterized in that the swing arms (8) are connected with the lifting arms (14) via linkages (12) , and that the platform (16) is divisible into at least two parts (18) which may be rotated in linkages (12) . 4. A lift according to claim 3, characterized in that linkages (12) are connected with means (20) for power transfer ensuring that lifting arms (14) and platform parts (18) rotate about substantially vertical axes. 5. A lift according to claim 3 or 4, characterized in that the platform (16) is provided with locking means (22) for coupling the parts (18) of the platform to- gether. 6. A lift according to one or more of claims 1-5, characterized in that the lift is provided with locking means ensuring that the platform does not unintentionally leave its travelling position. 7. A lift according to one or more of claims 1-6, characterized in that the swing arms (8) comprise threads (24) having a pitch which allows rotation of the swing arms (8) and thereby raising or lowering of the platform (16) by means of at least a nut (26) which is moved axi- ally to and fro on the threaded part (24) of the swing arms. 8. A lift according to claim 7, characterized in that the nut (26) comprises threaded holes having right-handed threads and left-handed threads, respectively. 9. A lift according to one or more of claims 1-6, char- acterized in that the swing arms (8) are connected with a gear which comprises a plurality of toothed wheels and at least a rack (27) . 10. A lift according to one or more of claims 1-9, char- acterized in that the lift is driven by an electrically, pneumatically, hydraulically or manually driven actuator (6) . 11. A lift according to one or more of claims 1-10, characterized in that the lift comprises a hinged plate (30) which creates contact between the platform (16) and the internal vehicle bottom (32) in the working position, and which shields the swing arms (8) at least partly in connection with the movement of the platform (16) . 12. A lift according to one or more of claims 1-11, characterized in that the platform (16) comprises at least two sections, at least one section of which is extensible and retractable. 13. A lift according to claim 12, characterized in that power for extension and retraction of the at least one section is applied by means of at least one scissors device. 14. A lift according to claim 12, characterized in that power for extension and retraction of the at least one section is applied by means of at least one rack device. 15. A lift according to claim 12 , characterized in that power for extension and retraction of the at least one section is applied by means of at least one wire pulling device. 16. A lift according to claim 12, characterized in that power for extension and retraction of the at least one section is applied by means of at least one spindle de- vice. 17. A lift according to one or more of claims 1-16, characterized in that the lift comprises a control unit, by means of which control unit at least one function may be operated. 18. A lift according to claim 17, characterized in that the control unit is hand-held and wireless. A lift for vehicles, e.g. vans and vehicles for the disabled Abstract An object of the invention is to provide a lift which does not obstruct general boarding of and disembarking from the vehicle, including when the lift is not in use. The novel and characterizing aspect of the lift according to the invention is that the lift comprises at least two swing arms (8) which are mounted at the vehicle bottom (10) , said swing arms being connected with lifting arms (14) which are mounted on the platform (16) , wherein the movements of the swing arms are synchronized and swing with opposite directions of rotation, and wherein the mount of the lifting arms comprises the feature that the mount of the rear end (14.2) of the lifting arms comprises at least a mount which at least allows displacement, and that the mount of the front end (14.1) of the lifting arms at least comprises a mount which at least allows rotation about at least an axis. When the swing arms are mounted at the vehicle bottom, it is ensured that, when the lift is not in use, the platform may be clear of doors or the like which are access paths to and from the vehicle. Moreover, the drive unit may be stowed away under the vehicle, if desired. When the movements of the swing arms are synchronized and swing with opposite directions of rotation, it is ensured that the movements of the swing arms obtain a common vertical component which is utilized for raising and lowering the platform. Fig. 1

Inventors: POULSEN POUL HAKON, POULSEN, POUL, HAKON
Applicants: POULSEN POUL HAKON, POULSEN, POUL, HAKON
Application year: 2001
Main classification: B60P1
IPC codes: A61G3, B60P1