Wheelchair lift

Start of patent duration: 1980 05 15 Longest possible duration:

© Issued on: 1961 01 12 © inventor:

© dependence:

3ÖÜ 348 © Pamphlets considered to delineate the state of the art:

US Pat. No. 4,027,807 DE-0S2646673

- 2 No.360348

The invention relates to a lifting device for a wheelchair, eg for boarding a vehicle, with a platform that can be raised and lowered, which consists of at least three adjacent, is formed approximately rectangular sections, those at their neighboring, are pivotally connected to each other transverse to the direction of desire longitudinal edges, the platform being movable on supports and rods between the ground and the desired height, and wherein the central portion of the platform is pivotable to an approximately vertical position, whereas the sections resting on both sides thereof remain in approximately horizontal position, so that the three articulated sections form a step.

Lifting devices, such as have been designed for use in vehicles in the past, have been relatively bulky and unwieldy and have required a lot of space in the vehicles. A lifting device that is fixed in vehicles is, of course, preferable. In addition, the size of the lifting device has often made it necessary to arrange at least a part of the same outside of the vehicle. The transport capacity of a vehicle has been severely limited by the size of the internal lifting device in most cases. Furthermore, the size and complexity of such lifting devices often required special openings to be cut in the sides of the vehicles to accommodate them. in addition to the normal entrances.

Furthermore, lifting devices that help handicapped persons overcome stairs in front of or in buildings have been very bulky and unconventional. These aids often proved to be an impediment to the use of stairs by normal persons and necessitated the installation of special doors and the installation of special ramps, which in addition had to be provided to normal entrances and staircases.

It has already become known a lifting device, which can be installed in the front door of a vehicle, with a platform provided here in their RuhesteRung the normal entrance level gebüdet. If the platform is needed, it can be operated by the driver without having to leave his driver's seat or by the disabled persons themselves from the entrance. The various step elements transform into a platform which can be lowered and raised to any position between the height of the vehicle floor and the ground level. Such a lifting device can be used in their Ruhesteüung as a normal staircase, so that it is fully integrated into this. The support frame and lifting mechanisms are mounted on each side of the step and in themselves do not interfere with the use and operation of the vehicle. There is no need to provide for the platform a storage space under or in the vehicle itself in these known Ausbungen. As an afterthought in these known embodiments it must be stated that the size of the platform is usually insufficient, since this does not exceed the total width of the three sections forming the step.

The object of the invention is therefore to provide a ro-hoist lifting device which can be easily installed in most conventional public transport vehicles or in buildings, with the possibility of producing a very large platform.

According to the invention, this is achieved in that the middle section of the platform is formed of two flat elements, which are pivotally held with their mutually remote edges on the adjacent platform sections, wherein the two flat elements, for example by means of a hydrauRschen device relative to each other in their common plane in the direction are displaceable transversely to their Längsrändem.

By means of these measures according to the invention, an extension possibility of the extended platform is achieved in a simple manner, without the need for additional push-out parts. In the retracted state, namely as a step element, then these flat elements are in their collapsed or contracted state of rest, so that they require virtually no special space.

Further details of the invention are explained in more detail with reference to an embodiment in the following description. FIG. 1 shows a perspective view of the lifting device, installed in the entrance of a public means of transport, in the extended position; FIG. Fig. 2 is a diagram of the electrical system; 3 is a perspective view of the support structure and the Hubvorriehtung in the extended SteUung. Figure 4 is a front view of the HubgesteRes; Figure 5 is a plan view of the HubgesteR with extended platform; 6 shows a section along the line VI-VI in Figure 3; Fig.7 a

- 3 No. 360348

Partial view in section, similar to Figure 6, wherein the platform, however, in the rest position, ie step-forming, is shown and Figure 8 is an exploded perspective view of the extendable section.

In the drawings, as an example of an application of this invention, a lifting device for lifting a wheelchair into the manhole of a public transport is shown. In Fig.6 the lifting device is shown extended in its lower position. The surface of the load-bearing platform -10- is by a level at a level -B- located section -1-, which normally terminates at rest with the vehicle floor, the surface of a section -3-- a stage -Α-, which extends outwardly, the associated vertical section -2- between the steps -A and B- (which lie flat) and the vertical section -4- formed under the step - A--. The four sections -1, 2, 3 and 4 are connected via hinges -5, 6, 7 pivotally connected to each other at their longitudinal edges. If the lifting device to be returned to its rest position (initial position), the surface of the section --3 "to the stage -A-- retracted and the upper portion -2- is raised to a vertical position, so that the surfaces of the sections - 1 and 2-- at two different heights the input levels.

The lower, rising portion -4- can, as shown in Figure 6, be used by pivoting as an inclined ramp on the platform --10-. This section -4- can also be folded upwards, as shown dashed in Fig. 6, to protect a load, such as the wheelchair, from rolling backwards during movement of platform -10-.

According to Figure 3, the lifting device has two horizontal support beams --11 and 12-, which are welded to the frame -13- of the vehicle -V- and arranged on opposite sides of the manhole. The support beams -11, 12- receive two vertically arranged, cylindrical rods -14, 15-, which are covered at the upper end with the horizontal part L-shaped struts -16-. The support beams -12- are preferably anchored to the end -18- on the wall of the vehicle. The struts -16- are anchored with their upper end -17- to the wall of the vehicle and with the lower end of the frame -13-. The vertical, cylindrical rods -14 and 15-, which form the guides for the lifting device, the support beams -11 and 12- and the struts -16- are the supporting frame of the lifting device or the fixed parts of the same.

The moving parts of the lifting device consist of the articulated platform sections -1, 2, 3 and 4 and the associated parts forming the platform -10-. These parts are mounted on a substantially U-shaped frame -32- where they slide vertically along and between the two rods -14 and 15-. As shown in Figures 4 and 5, this frame has a lower termination formed by two beams -23-. These beams -23- are interconnected by two rectangular sliding plates -24- and flanked by two lateral elements which project upwardly from the base.

Each side member is formed by two vertical parts -25 and 26- which are fixed to the beam -23- and cross members -27 and 28-. Each side element is held by its upper end by brackets -31- and in the central region by brackets -29- slidably on the rods -14- and by a strut -30- to the bars -15-. Some cylinder tubes -35, 37 and 39- with a surface conforming to the convexity of the cylindrical rods -14 and 15- are attached to the brackets -31, 29- and the brace -30-. These cylindrical rollers can also include the rods -14, 15- and guarantee a smooth and stable movement of the frame -32- along the guides. Two hydraulic cylinders -19- are connected with their upper closed part to the horizontal part of the struts -16- via a bolt -20-. The pistons are connected with their outer ends via linkage -21- and bolt -22- with the beam -23-. Through these hydraulic cylinders -19- and the linkage -21- the frame -32- along the rods -14 and 15- is moved.

The platform section -1-, which leads to the step -B- is displaceable between the vertical sections -25 and 26-, these sections -25 and 26- also acting as vertical guides in the folding movement. Two hydraulic cylinders -36- are attached with their closed ends to the cross members -27-. The pistons are connected at their free ends by links -38- to the opposite ends of the platform section -1 , thus causing the vertical movement of the step -B- along and between the sections -25 and 26-.

- 4 No. 360348

Since the hoisting device is installed in the entry lugs of the right front side of a public transportation, and the driver's field of vision is not to be impaired, the right side support beams -11, 12- and right-side struts 16 are mounted at a lower level than the elements the opposite left side. The right side part of the frame is therefore shorter than the left side part. The stop limiters -8 and 9- are needed to compensate for the height difference and the hydraulic cylinders -19 and 36- to hold or to maintain sufficient height to ensure the desired lifting action.

The platform section -3- which forms the step -A- is connected to the beam -23- by a telescopic telescopic element -59-. There are three Teleskopelemente -58, 59 and 60 are provided jeweüs. These known types of telescopic telescopic members are used to provide the lowest possible friction between the mechanical sliding surfaces. The telescopic elements -58- are slidably mounted on the inside of the beam -23-. The telescopic elements -59- are slidably disposed in the telescoping elements -58- and support the platform section -3-. The telescopic elements -60- are connected to the telescopic elements -59- and run pointed to the front of the platform and carry the section -4-. The two telescopic elements -60- are connected transversely by an end bar -56-. A self-adhesive pressure switch strip -57- is mounted along the length of the end bar -56-.

The vertical section -2- of the step - B- contains two telescopically connected flat elements -41 and 43-. The upper flat element -41- is connected with its one edge pivotally connected to the section -1- the stage -B-. The lower flat element -43- is connected at its opposite edge pivotally connected to the section -3- the stage - A-. The mutually facing longitudinal edges of the flat elements -41, 43- are provided with recesses in the form of a non-interlocking interlocking pattern, as shown in Figure 8. The lower flat element -43- is inserted between a cover plate -42- and a support plate -44-. The upper flat element -41- engages telescopically and partially into the recesses. A stepped cover -40- with flanged edges -49- is fixed to the upper flat element -41-. The edges are bent down to make a sliding space for the cover plate -42-. The flat elements -41 and 43- are held by a pair of springs -45 and 46- at the smallest common distance. These springs -45 and 46- are fastened to the lower flat element -43- by means of bolts -47- and to the upper flat element -41- by means of bolts -48-.

If the platform is in the starting position, as shown in FIG. 7, then the vertical section 2- can run in at its smallest distance under the tension of the springs -45 and 46-. When the platform is fully extended, as shown in Figures 3 and 6, section -2- is extended to its maximum width to provide an additional load-bearing surface. Two hydraulic cylinders -52 and 53- are juxtaposed with their piston rods -51 and 54- extending in opposite directions. The end of the piston rod -51- is connected to a support -50- in the lower rear corner of the frame -32-. The end of the piston rod -54- extends into a smaller-diameter rod -55-. The rod -55- penetrates a recess in the middle of a tab -64- which is connected to the platform portion -3- of the stage -A- and connected to the end of the end bar -56-. When the piston rods -51 and 54- extend under pressure, the end bar -56- is first pushed forward, causing the higher-level portion -4- of the stage -A- to rotate upwards about the pivotable connection of the hinge -7-, until an access ramp to a platform -10- emerges, as shown in FIG. Now, the piston rod -54- comes into contact with the tab -64- and begins to push forward the platform portion -3- of the stage -A-. This Vorwärsbewegung is coordinated with a downward movement of the platform portion -1- the stage -B- under the influence of the hydraulic cylinder -36-. As the piston rods of the hydraulic cylinders -52, £ 3- continue their movement, the extendable, ascending portion -2- of the stage -B- is extended to its greatest extent between the platform sections -1 and 3-. If the platform -10- loaded with a wheelchair, so the section -4- the step -A- can be folded up under the action of the lever -62-, which is connected to a hydraulic cylinder -61- to a support angle for the wheelchair to be brothers.

The pressure switch bar, which is mounted along the outer edge of the end bar -56- is made of flexible material. Any pressure on the bar by contact with any object

Is exercised by a liquid on a pressure switch, which is part of the electrical safety system. Grooved plastic or rubber mats are preferably used to cover the steps and the platform surface to ensure adequate safety.

Referring to Fig.2 together with the other drawings, the operation of the ⁵ Lifting device described: The lifting movement of the hydraulic cylinder -19- (Figure 3) is controlled by a solenoid valve -138-; the lowering movement controls the solenoid valve -139-. The outward movement of the cylinders -52 and 53- (Fig.6) is controlled by the solenoid valve -115-; the inward movement through solenoid valve -116-. The step-down movement of the hydraulic cylinder -36- (Figure 4) monitors the solenoid valve -114-; the step elevator movement that

1 ° solenoid valve -117-. The electrical power supply is provided by the vehicle battery -100, protected by fuses -101 and 102-. Manual switches -150, 151, 152 and 153- are accessible from the driver's seat or from the entry area of ​​the vehicle and allow the driver or the user of the lifting device to control the operation. The hand switches -150, 151 and 152- are preferably of a type which go back to the "off" position when released. The as¹⁵ Three-point switch for tired manual switch -150- controls the position of the switching element -140- and is required to raise or lower the push-button -32-. The handset switch -151-, which is also designed as a three-point switch, acts on the sighting element -119-, which is required to extend or retract the platform. The manual switch -152- acts on the switching element -109- to raise and lower the section -4- as the securing flap for the rooftop chair.

The hand switch -153- acts on the switching elements -130 and 131- and pulls the lifting device back to its initial position. While the manual switch -153- is in the normal position, holding the manual switch -150- in the down position, the solenoid valve -139- is powered by the switching elements -131, 127, 128 and 104-. The coil -103- of the magnetic switch -145-, which controls the pump, is supplied with power and the pump -143- works, which causes the lowering of the

Frame -32- through the hydraulic cylinder -19- has the consequence. The held in the "up" position band switch -150- leads to the solenoid valve -138- through the switching elements -130, 129 and 104- power to. The pump -143- is likewise set in motion and the platform -10- extended by pulling the platform -3-3 under the action of the cylinder -52 and 53-, while the platform section - 1- is lowered with simultaneous action of the hydraulic cylinder -36- , The manual switch -151- held in the "on" position supplies power to the solenoid valve -116 and 117- through the switching elements -118, 123 and 104-. At the same time the pump -143- starts to work and the platform -3- is retracted under the action of the hydraulic cylinders -52 and 53-, whereby the platform section - 1- is raised with simultaneous action of the hydraulic cylinders -36-. While the manual switch -152- is in the locked position, the solenoid valve -108- of the

Hydraulic cylinder -61- by the switching elements -109 and 106- activated. The lever -62- moves around the bolt -63-, which turns the section -4- upwards around the hinge -7-. If the manual switch -152- is in the unlocked position, the action of the hydraulic cylinder -61- with the solenoid valve -107- is reversed by the switching elements -109 and 106-, as a result of which the section -4- returns to the starting position.

The various mechanical movements are further controlled by the subsequently gescherederten switching devices. In most public transportation, the opening mechanism is coupled to the brake system to prevent inadvertent opening of the vehicle door while driving. To block the operation of the hub device while the door is closed or the vehicle is in motion, the electrical power supply passes over the pole of a switching element coupled to the vehicle door which closes the switching element -104- only when the door is fully open. A limit switch for the downward movement opens the switching element -128- when the linkage -21- (Figure 3) has reached its maximum extension travel and thus stops the pump -143-. An up-shift limit switch opens the switch element -129- when the platform -10- has reached the height of the vehicle floor -F- to stop further lifting movement of the platform. An outward travel limit switch opens the switch element -122- when platform -10- is fully extended to prevent further movement. A limit switch for inward movement opens the switching element -123- when the platform -10- is fully retracted to cancel further movement.

- 6 Nr.360348

A modular type contact switch is placed under the sliding plates -24-, closes the switching element -125- when the platform touches the ground or an obstacle, thus energizing the coil of the fault relay, thereby opening the switching element -127-. This then interrupts the further downward movement of the platform -10-. A limit switch, which stops the downward movement, closes the switching element -118- when the section -4- is folded down as a support for the wheelchair, to allow retraction of the section -3- only when the section - 4 is lowered , A platform exit limit switch closes switch element -106- when the platform is fully extended to prevent section -4- from being deployed while section -3- is still retracted. A home position switch opens the switching elements -136 and 137- when the platform -10- has reached its normal step position to prevent further upward or downward movement of the platform when the handset -153- is in the home position position.

A pressure switch disposed along the end bar -56- closes the switching element -105- whenever the platform encounters an obstacle and thus supplies power to the coil of the relay -112-, thereby opening the switching element -113- and prevents further extension of platform -10-.

The normal sequence of movement is as follows: After opening door -D- of vehicle -V- the manual switch -153- is set to normal position. The driver holds the handset -150- in down position until the frame -32- touches the ground. After releasing the manual switch -150- he holds the manual switch -151- in the off position until the platform -10- is fully extended. After loading the wheelchair onto the platform -10-, the support bracket forming portion -4- is raised by temporarily holding the manual switch -152-.

The platform -10- is raised to the height of the vehicle floor - F- by holding the manual switch -150- in the up position. After retracting the wheelchair into the vehicle, the handset -153- returns to its original position. Section -4- is lowered by operating manual switch -152- in the unlocked position. Stand -32- is lowered to the height of the home position by holding hand switch -150- in the off position, and platform -10- is retracted to the home step position by holding the next hand switch -151- on. Position. The sequence of operations is reversed when an elevator is returned from the vehicle to the ground. The Gesteh -32- can also be lowered and lifted without the steps - A and B- to open the platform.

A lever -144- is mounted on the pump -143- for manual operation of the valves in order to operate the lifting mechanism even in case of failure of the electrical device (short circuit). The pump itself is preferably mounted near the entrance and / or the control switch. From this application of the invention described herein, modifications are possible without affecting the essence of the invention. For example, an electric motor could be used to take over the operation of the wheelchair lift in place of the described mechanism. Of course, other structural modifications of the invention are possible, which are within the scope of this invention. The lifting device according to the invention can also be installed in other types of stair structures, eg in homes with different floor levels, at building entrances or as part of a loading dock.