EP2158152B1 - Scissor lifting platform - Google Patents

Description

The invention relates to a scissor lift, especially for vehicles, with two attached to or in the ground support or bottom rail, with at least two intersecting scissor beams, which are held and guided with their lower ends in the support rails, with one of the two scissor struts approximately centrally interconnecting joint, with an attacking on the scissor beams Hubaggregat for spreading and moving together of the scissor struts and with support rails or rails, the contact areas in their end areas for example Have vehicle wheels and are supported on the upper ends of the scissor struts, one of the scissor struts is pivotally connected at its upper end with a support rail, and the other scissor stay is guided longitudinally displaceable with its upper end to the support rail during lifting and lowering.

Scissor lifts are used in various technical fields for lifting various loads and possibly even people. According to their preferred use, a variety of constructive solutions in use, for example, as load lifts in rack storage, as stationary or mobile platforms, forklift od. Like. Different versions of scissor lifts are also used for lifting motor vehicles, especially cars, SUVs and vans, in repair shops, in manufacturing plants and also in testing operations, due to the simple hub technology, the robust design and the possibility of a ground level arrangement of the retracted scissor lift.

Known scissor lifts for lifting motor vehicles, as od in repair shops, testing companies. Like. For lifting lighter motor vehicles, such as cars, SUVs, vans, etc., are used, regularly have two on the ground or underfloor stationary in the ground arranged support - or guide rails made of formed flat steel or sheet metal. The distances between these two parallel support rails correspond approximately to the wheelbases of the vehicles to be lifted. In one end region of each of these support rails, a bearing arrangement is provided, on which the lower end of a scissor spar is articulated and immovably supported. In longitudinal guides of the support rails, the lower end of the second scissor strut is guided longitudinally displaceable and articulated. Both scissor beams are pivotally connected to each other in their central region by a bearing pin. On the upper ends of each Scherenholm pair a support rail is supported. Since the two scissor beams of each scissors-spar pair are connected to one another in the center, the respective carrying or running rail extends substantially horizontally. The upper end of each scissor spar is hinged to an end portion of the support rail and the upper end of the other scissor spar is guided longitudinally displaceable in guide elements of the support rail during spreading and moving together of the support bars.

In this type of lifting platform, certain instabilities and not exactly horizontal orientations of the upper mounting rails, which are usually referred to as running rails in vehicle lifts, can result under load. The cause of this possibility of error is the longitudinally displaceable support of the upper ends of a scissor struts. Under load, the rail can be lowered slightly on one side, whereby it is deflected from its alignment parallel to the ground. If axle measurements of vehicles on a scissor lift are to be carried out, this slight inclination of the rails can lead to corresponding incorrect measurements. So far, such a behavior has been countered by scissor lifts by a more robust design with increased material costs.

The DE 296 10 999 U1 describes a scissor lift table having a pair of scissor arms connected together at a crossing joint between a bottom sub-frame and an upper table platform.

The object of the invention is to provide a scissor lift, which ensures improved stability and rigidity even with asymmetric loads without excessive overhead and costs.

This object is achieved by the features specified in claim 1. Further preferred developments are described in the dependent claims.

In the scissor lift according to the invention, the lower and the upper ends of all scissor beams are locked to the associated supporting or mounting rails in a fully or partially raised position, so that the rails are fixed and supported at fixed symmetrical points to the vertical center plane. As a result, inclinations of the rails are under heavy load safely avoided even with asymmetric load distribution, so that axle measurements of an upright vehicle can be performed with high accuracy.

As a means according to the invention for locking the upper ends of a scissor spar on the associated running rail a locking mechanism is advantageously used, which has a sliding member guided longitudinally on the profiled running rail and at least one locking element which can be positively or non-positively lockable on the running rail. The longitudinally guided sliding member is expediently designed and arranged so that it is from the vehicle on the rail on the locking or. Locking mechanism can absorb applied load forces without excessive friction in the lifting and lowering movements.

According to an expedient embodiment, the locking mechanism has front and rear sliding elements guided inside the profiled rail and front and rear jointly actuatable locking elements, and also a central bearing arrangement, on which the upper end of the scissor beam is articulated approximately symmetrically between the sliding elements and the locking elements. By this configuration, a sufficiently elongated guide between the rail and the locking or locking mechanism is achieved and in the locked state is a double locking means of the front and rear locking elements acting positively as claws or teeth or frictionally acting as wedges on mating members, the the rails are attached. Since the bearing arrangement of the upper end of the pivoting spar is arranged symmetrically between the front and rear sliding elements and the front and rear locking elements, there is a symmetrical distribution of the friction forces during lifting or lowering and the locking forces during locking.

According to a further advantageous embodiment of the invention, the locking elements of the respective locking mechanism are actuated jointly and simultaneously by a drive, wherein for this actuation of the locking elements, an electrical, mechanical or fluidic linear drive can be used.

An effective and reliable operation of the locking elements is advantageously achieved with a drive unit which is fixed to a front end of a box-shaped housing, on which the sliding elements, the locking elements and in the middle part of the support bearing for articulating the upper end of the scissor beam are provided. In this embodiment, the simultaneous actuation of the front and rear locking elements by means of a slide which is moved via a plunger from the drive in the housing and actuators for pivoting the locking elements from its engaged position against the force of leaf springs.

As counterparts for the tooth-like locking elements racks can be used, which are attached to the side walls of the rails with inwardly facing teeth. If the locking between the upper end of the scissor beam and the running rail by frictional engagement, for example by wedging, takes place, instead of the racks, a dimensionally stable bar with high friction and as locking elements suitably shaped wedges can be used.

Furthermore, the scissor lift can be characterized in that at the upper and / or lower end of a scissor stay a locking mechanism is articulated, the one on the running rail and / or on the guide rail positively and / or kraftschlüßig lockable locking element, and a detent element, wherein the detent element a Can have a plurality of substantially identically formed detents, wherein the locking element in a plurality of detent positions with at least one detent can be releasably, positively and / or non-positively engageable. At least in a partial region, at least a first detent position, a second detent position and a third detent position can be approachable with the locking element, wherein at least a first distance between the first detent position and the second detent position and a second distance between the second detent position and the third detent position, may have different lengths. It is well known to those skilled in the art that by corresponding numbering of the latching positions at least a first distance between the first latching position and the third detent position and a second distance between the second detent position and the first detent position may have different lengths. The detent device may further include a force member for generating a relative movement between the detent member and at least one detent. In this case, the notches may have different distances from one another in at least one subregion of the detent element. As a result, the number of possible locking positions can be reduced to a smaller number of predetermined locking positions in a particularly simple manner, whereby the time required to find the equidistant locking positions is significantly reduced.

Furthermore, the detent element can be connected to the guide rail, running rail and / or to a workshop floor, wherein the detents of the detent element can have a different pitch in the longitudinal direction of the detent element.

Furthermore, the detent element may have a first portion in which the first distance between two adjacent detents and the second distance between two adjacent detents is the same, and have a second portion in which the first distance between two adjacent detents and the second distance between two adjacent latches is different, wherein the length values of the distances between each two adjacent notches in the longitudinal direction of the detent element continuously, steadily, abruptly and / or discontinuously increase or decrease. This results in the advantage that within a certain initial height, a plurality of different detent positions can be approached and outside this initial height only a smaller number of predetermined detent positions are ingestible.

Furthermore, as the lifting height of the lift increases, substantially in a vertical direction, the pitch of the ratchet element becomes substantially larger in the horizontal direction.

Furthermore, a guide unit may be provided, which may be in communication with the detent element in such a way that the Verrieglungselement can be latched only in predetermined positions with the detent element. This results in advantages in that the locking element can engage with the locking element only in predetermined locking positions and thus erroneous hooking between locking device and locking element is excluded. In addition, the guide unit has the advantage that even with the use of a detent element whose adjacent detents have the same distances over the entire length of the detent element detent positions can be predetermined, characterized in that the distances between adjacent detent positions have different lengths. Similarly, even in the sub-region of the detent element in the adjacent detents may have the same distances from each other, be ensured by means of the guide unit that the locking unit in this area can only take detent positions have mutually different distances.

Furthermore, the guide unit may have an outer contour and the locking element having an actuating means which is engageable in predetermined positions with the contour of the guide unit in contact, whereby in these positions a contact between the locking element and the latch member can be prevented. This has the advantage that also different locking positions can be adjusted later by changing the contour or by using an exchangeable guide means.

Furthermore, the locking element may be a rack and the detents teeth, wherein the locking element may have at least one tooth which is engageable with at least one tooth of the rack. Furthermore, the locking element may be a perforated rail.

Furthermore, the force element may be a hydraulic cylinder, a stepper motor, an electromagnetic actuator, a spring element and / or a pneumatic cylinder.

Furthermore, the locking mechanism may comprise a dimensionally stable housing, which may communicate with the locking element via a hinge, wherein a first end portion of the force element may communicate with the locking element and a second end portion of the force element may communicate with the housing.

Furthermore, the locking element may comprise at least a first tooth and a second tooth, wherein the detents may comprise a first detent unit and a second detent unit, wherein in each case a first tooth and / or a second tooth with a first detent unit and / or a second detent unit in engagement can be brought. By using a catch with two locking units and a locking element with two teeth, a double engagement and thus a particularly secure locking can be ensured.

Furthermore, the scissor lift may have a control unit with which the lifting unit can be controlled in such a way that the running rail reaches a first predetermined lifting height by a lifting movement and reaches a second predetermined lifting height after reaching this lifting height by a lowering movement. As a result, a complete and secure locking of the locking mechanism with the locking element can be ensured in a particularly simple manner.

Furthermore, after reaching the first predetermined lifting height and before and / or during reaching the second predetermined lifting height, the force element of the locking mechanism can be controlled with the control unit in such a way that the locking element can be brought into positive and / or non-positive engagement with the rack.

Furthermore, at least before and / or during the reaching of the second predetermined position, a force element actuate the locking element such that the locking element with a detent of the locking element form and / or non-positively engageable and thereby corresponds to the second predetermined position of a locking position.

Furthermore, to cancel the engagement between the locking element and a detent, the control unit to drive the drive unit such that initially a lifting movement can be generated and then lowering movement can be generated. It can be controlled such that the positive and / or non-positive engagement of the locking element is released with a catch of the locking element between the end stroke movement and the beginning of lowering, and / or during the lifting or lowering movement with the control unit. Thus, a complete unlocking of the locking mechanism and the locking element can be ensured in a particularly simple manner.

In summary, the advantages of the invention will be listed again below. By providing a detent element whose individual detents have different pitches at least in a partial region of the detent element, it can be ensured that the predetermined stroke positions in which a hoist can be locked have an equidistant, vertical distance from each other, although in the lateral direction the detent element has different path lengths from rest position to rest position performs. By providing a guide unit can be ensured in a particularly simple manner that an unwanted hooking of the locking element can occur with the locking element. This is particularly advantageous when using a locking element with two teeth and a catch with a first latching unit and a second latching unit, in which there may be the risk that a second tooth may hook unintentionally with a first latching unit. This problem arises in particular in the case of insufficient pressurization of the force element, whereby the locking element is not completely retracted into the housing and can jam due to the different pitch of the second tooth of the locking element on a second locking unit and thus can lead to the inoperability of the entire lift , Furthermore, it can also be ensured that an incomplete unlocking of the locking mechanism, in which both teeth of the locking element with the detent remain in contact is prevented, whereby a blockage of the lifting system is averted.

Fig. 1

eine Scherenhebebühne für Kraftfahrzeuge in perspektivischer Darstellung,

Fig. 2

einen vergrößerten Ausschnitt A in Fig. 1,

Fig. 3

einen vergrößerten Ausschnitt B in Fig. 1,

Fig. 4

einen Teil des bei der Scherenhebebühne nach Fig. 1 eingesetzten Verriegelungsmechanismus in perspektivischer Darstellung,

Fig. 5

den Teil des Verriegelungsmechanismus nach Fig. 4 im Schnitt.

Fig. 6

eine perspektivische Ansicht der Arretiervorrichtung,

Fig. 7

einen Längsschnitt durch die Arretiervorrichtung,

Fig. 8

eine Scherenhebebühne mit erfindungsgemäßer Arretiervorrichtung,

Fig. 9A

eine Seitenansicht des Rastenelementes,

Fig. 9B

eine Seitenansicht des zweiten Teilbereiches des Rastenelementes.

Hereinafter, a Scherenhebebü will be described for motor vehicles as an embodiment of the invention with reference to the drawing in detail. Show it

Fig. 1

a scissor lift for motor vehicles in perspective,

Fig. 2

an enlarged section A in Fig. 1 .

Fig. 3

an enlarged detail B in Fig. 1 .

Fig. 4

a part of the scissor lift after Fig. 1 used locking mechanism in perspective view,

Fig. 5

the part of the locking mechanism after Fig. 4 on average.

Fig. 6

a perspective view of the locking device,

Fig. 7

a longitudinal section through the locking device,

Fig. 8

a scissor lift with inventive locking device,

Fig. 9A

a side view of the detent element,

Fig. 9B

a side view of the second portion of the detent element.

In the Fig. 1 illustrated scissor lift is used for lifting lighter motor vehicles, especially passenger cars, SUVs, vans, etc. The lift has two support rail structures 1, of which in Fig. 1 only one is visible and the second is covered. In the in Fig. 1 left half consists of 5tützschienenkonstruktion 1 of two mutually parallel longitudinal beams 2, 3, which are connected in its central region by a transverse web 4, on which a central pin 5 is fixed. In the Fig. 1 left end portions of the two side members 2, 3 are connected by an approximately plate-shaped cross member 6 firmly together, on the end of each two bearing blocks 7, 8 are fixed. In these bearing blocks 7, 8, a horizontal pivot pin 9 is mounted with its ends, at the center of a support joint 10 is attached to the articulated support of a pressure medium cylinder 11. Ummittelbar next to the inner sides of the two bearing blocks 7, 8 are attached to the pivot pin 9 two dimensionally stable narrow support bars 12,13 with tapered end portions, which together form a scissor stay 14.

The in Fig. 1 right part of the support rail construction 1 includes two parallel longitudinal rails 15, 16, each having an inwardly open cross-section and are connected to a bottom flat iron 17. On each of the lateral support rails 15, 16, there is provided a locking mechanism 18, 19 hinged to the lower tapered ends of each support beam 20, 21, respectively. These two support beams 20, 21 together form a second scissor stay. As shown, the two support beams 13 and 20 and the two support beams 12 and 21 are pivotally connected to each other by central bearing pins 22, 23. The piston of the pressure medium cylinder 11 engages a translation pivot lever linkage, which is mechanically coupled to the two crossed scissor struts. When the pressure medium cylinder 11 is pressurized fluid and thereby extends its piston rod, there is a spreading of the two scissor beams.

The upper tapered ends of the two beams forming the first scissor beam 14, 12 are connected by a transverse bolt 25. Each end of this transverse pin 25 is rotatably mounted in a locking mechanism 26, which will be described below with reference to FIG Fig. 2 will be described in more detail. In the FIGS. 1 and 2 in each case only one of the two locking mechanisms 26 is shown, which form end-side bearing arrangements for the transverse or bearing pin 25. These two locking mechanisms 26 are mirror images-equal, so that only one mechanism based on the Fig. 2 is described.

As in Fig. 1 is shown on the upper ends of the two scissor beams forming Tragholmpaare 12, 13 and 20, 21 each support a support rail 28, the two front footprints 29, 30 on its upper side and at its rear end a turntable 31 and transverse plates 32 carries. At the front, in Fig. 1 left end of the rail 28 is a ramp 33 hinged. The rail 28 has a flat upper surface and two vertically angled side walls 34, of which only the front is visible.

In the above, only one half of the in Fig. 1 described scissor lift described. The second half of this lift is designed to be identical and arranged in a horizontal intermediate distance, which corresponds approximately to the track width of a motor vehicle to be lifted. In the Fig. 1 Front and rear half together form the scissor lift for raising and lowering a motor vehicle. In the Fig. 1 The rear half of the scissor lift has the same components as the front half, which are marked with the same reference number marked with an index mark.

A vehicle to be lifted travels with its wheels via the ramps 33, 33 'onto the lowered rails 28, 28'. For measuring, for example, the wheel axles of the motor vehicle, the wheels are positioned on the contact plates 29, 29 ', 30, 30' and 31, 31 'and the lift is raised in its raised position by controlled pressure medium supply to the pressure medium cylinders 11, 11'. In the predefined extension position, eg in Fig. 1 is shown, the locking mechanisms 18, 19 are activated in the bottom area and the other locking mechanisms 26 on the upper rails, so that the scissor beams and thus the entire scissor lift are fixed in the selected position. By this activation of the locking mechanisms 18, 19 and 26 and slight longitudinal displacements of the bearings at the lower ends of the scissor struts 20, 21; 20 ', 21' as well as the bearing assemblies at the upper ends of the scissor struts 12,13; 12 ', 13' prevents, so the in Fig. 1 also can not tip off the right parts of the rails slightly under load.

Fig. 2 shows on an enlarged scale the section A in Fig. 1 in which one of the locking mechanisms 26 for fixing the upper end of the one supporting beam 13 to the running rail 28 is shown. From the flat top of the rail 28, the two side walls 34 are bent in one piece down while also a suitable frame construction can be selected with support plate. In a recess 37 of the top of the rail 28, the turntable 31 is arranged with the circular footprint. Before the angled recess 37 extends the transverse or bearing pin 25, which is connected at one end to a tapered end portion of the support beam 13 and a locking mechanism 26. On each side wall 34 of each rail 28 a rack 38 is fixed with inwardly facing teeth 39, which extends between two upright narrow plate blanks 40, 41 and whose back is facing the inside of the side wall 34 depending. This rack 38 is secured by suitable means, such as bolts, Welds or the like permanently attached to the inside of the associated side wall 34 of the running rail and forms the stationary part of the locking mechanism 26. With the inwardly facing teeth 39 of the fixed to the rail 28 rack 38 are each two tooth claws 42, 43 in engagement eg in Fig. 5 enlarged shown in section. These tooth claws 42, 43 are pivotably mounted in an elongated rectangular stable housing 45, so that their teeth 46 can engage in corresponding tooth gaps of the toothing 39 in the toothed rack 38 (cf. Fig. 4.5 ). On the upper side of the housing 45, a plurality of sliding elements 46, 47 are attached, which are formed in the present case as pressure-resistant Gleitklötze on which optionally coated sliding surfaces 28 rest. The weight forces of the loaded or unloaded rails 28 are transmitted via the sliding elements 46, 47 and the correspondingly stable housing 45 and the bearing pin 25 in the respective scissor struts.

Fig. 3 shows the support of the lower tapered end portion of the scissor beam 20 enlarged in the cutout B in the support rail 2 in Fig. 1 , The longitudinal rail 15 has a vertical wall section 50 and an upper horizontal section bent portion 51, wherein the region of the bend is covered by an outer arcuate plate 52. On the vertical wall portion 50 of the longitudinal rail 15, a laterally horizontally projecting plate 53 is fixed, in which mounting holes are provided. On the inside of the vertical wall portion 50, an elongate rack 55 is mounted with inwardly facing teeth 56, which extends on the outer side portion of an elongated narrow bottom plate 57. The rack 55 forms the stationary part of the locking mechanism 18, with which the lower end of each of the scissor struts is releasably secured to the associated support or bottom rail. This fixation is carried out by two successively pivotally mounted in a housing 58 tooth claws 60, 61, the constructive and functional in the Fig. 5 shown in section tooth claws 42, 43 of in Fig. 1 and 2 represented upper locking mechanism correspond. The lower tapered end of the associated scissor beam 20 is rotatably mounted in the housing 58 via a transverse pin 62. On the housing 58, a sliding plate 64 is arranged, which ensure a precise straight guide of the locking mechanism with disengaged inactive tooth claws.

In the FIGS. 4, 5 is the upper locking mechanism according to section A in Fig. 1 in a perspective view and shown in horizontal section, wherein the after Fig. 2 on the housing 45 fastened sliding elements 46, 47 are not shown. At the in Fig. 4, 5 left end face of the housing 45, a drive element 67 is attached, which is formed here of pressure medium cylinder with a piston 68 and centrally attached thereto piston rod 69. The cylinder 67 is supplied with pressure medium via a length-adjustable trailing line 70. The free end of the piston rod 69 protrudes into a free space 71 in the housing 45 and is fixedly connected via a screw to a slider 72 formed of an elongate sheet metal blank, which in FIG Fig. 4 is completely shown in plan view. In Fig. 5 The various individual parts of the slider are each provided with the reference numeral 72. In the free space 71 of the housing is the double-toothed claw 42 and in a second free space 73 in the housing 45 on the other side of the pin 25, the second double-toothed claw 43 is pivotally mounted about a pin 75. The two double-toothed claws 42, 43 are constantly acted upon by an engagement force, which is exerted by a respective leaf spring 76, 77. Each of these leaf springs 76, 77 presses with its upper end against a respective projection 78, 79, which is integrally formed on each double-toothed claw 42, 43 in the upper right corner area pointing upwards. Each leaf spring 76, 77 presses against the back of the associated lug 78, 79 and exerts a torque acting in the closing direction on the associated double-toothed claw 42, 43, so that their teeth engage in the tooth gaps of the rack 38. How out Fig. 5 Removable, the teeth 39 of the rack 38 and the teeth of the two double-toothed claws 42, 43 are asymmetrically formed such that upon movement of the transverse pin 25 with the housing 45 in Fig. 1 to the right the teeth of the Double tooth claws 42, 43 slide out against the force of the leaf springs 76, 77 from the corresponding tooth gaps of the rack 38. By applying the cylinder 67 with a pressure medium whose piston 68 in Fig. 5 shifted to the right, whereby its piston rod 69, the slider 72 moves to the right and presses against each of the lugs 78, 79 on the tooth claws 42, 43. This pressure leads to a simultaneous and common pivoting movement of the two tooth claws 42, 43, the teeth of the teeth 39 of the rack 38 free.

The transverse pin 25 has at each end a narrower pin 80 which is rotatably supported via a bearing bush 81 in a recess in the housing 45.

In Fig. 6 a locking device 201 is shown, which has a dimensionally stable housing 206 in which a locking element 202 is inserted (not visible). The locking member 202 may be engaged with a detent member 100. The detent element 100 has identically designed detents 204, which each have a first detent unit 241 and a second detent unit 242. On a side surface 110 of the detent element 100, a guide unit 104 is provided which has flat elevations 108. The distances between the elevations 108 essentially correspond to the distances between the detents 204. The guide unit 104 is aligned with the detent element 100 such that its elevations 108 laterally cover the respectively second detent unit 242 of the detents 204. Furthermore, in Fig. 6 to recognize the actuating means 106, which is arranged on the locking element 202 and is in communication with the guide unit 104. During a lateral movement of the locking mechanism 1 along the detent element in the direction of the arrow L, the actuating means 106 comes into contact with the contour 105 of the guide unit 104 in the region of the elevations 108. As a result of this contact, the actuating means 106 blocks the locking element 202 and as a result does not allow the locking element 202 to extend.

In Fig. 7 is a side sectional view shown in the longitudinal direction by the locking device. In the interior of the dimensionally stable housing 206, a force element 205 is provided, in the form of a hydraulic or pneumatic cylinder.

In an embodiment not shown, the force element may be a stepping motor, an electromagnetic actuator or a spring element.

The force element is connected in a first end region via a rotary joint 209 to the housing 206 and connected in a second end region via a rotary joint 208 with the locking element 202. The locking element 202 is rotatably mounted in the housing 206. By actuation of the force element 205, the locking element 202 can rotate about the rotation axis 207 and thereby be moved into the housing 206 or out of the housing 206, so as to be transferred into a locking or unlocking position.

The locking element has two teeth, a first tooth 221 and a second tooth 222, which engage in a locking position with a respective first latching unit 241 and a second latching unit 242 of a detent.

Fig. 8 shows a side view of a scissor lift to which the locking device according to the invention finds exemplary use. The locking element 202 is mounted on a first component 211, namely on a laterally displaceable upper end of a scissor bar 211. The detent element 100 is mounted on a second component 28, for example a running rail 28. The first component 211, the scissor stay 211, is rotatably connected at its lower end to a third component 101, a foundation or a bottom plate.

A corresponding arrangement is in Fig. 8 also shown for the second scissor beam, wherein a laterally displaceable lower end is connected to the locking mechanism and an upper end is rotatably connected to the running rail 28 in connection. The scissor lift shown above has from a certain initial height y1 uniform, vertical distances y for locking positions, which can be approached with the lift. In order to realize these equidistant distances, the locking elements 100 must have a different pitch of the teeth in the horizontal direction. This pitch increases with increasing lifting height of the running rail 28 in the lateral direction, shown by the distances xn, xn + 1, xn + 2, x ..., where xn <xn + 1 <xn + 2 <x ....

Furthermore, in Fig. 8 a control unit 107 can be seen, which is in communication with the lifting unit 109. The lifting unit is in communication with the two scissor beams of the scissor lift in such a way that, when actuated, it can spread or contract the scissor struts against each other. With the control unit 107, on the one hand, the lifting unit 109 can be controlled, and on the other hand the force element 205 in the locking mechanism 201.

When the lift is to be lifted and locked in a lock position 1 corresponding to a height resulting from the value y1 + 3 · y, the control unit 107 controls the lift unit 109 so that the lift height is driven to a height, which is substantially slightly higher than the locking position 1, but lower than a lifting height, which is composed of the value y1 + 4 · y. When this first lifting height is reached, the force element 205 is controlled via the control unit, so that the teeth 221, 222 of the locking element penetrate into the recesses of the locking units 241, 242, wherein the locking element 202 is rotated out of the housing 205. Subsequently, the lifting unit 109 is controlled such that the running rail performs a lowering movement and the locking position 1 assumes, wherein the teeth 221 and 222 with the locking units 241 and 242 firmly engaged.

To remove the lift from the detent position 1 and release the lock, the lifting unit 109 is driven so that initially a slight lifting movement is performed, the rail occupies a lifting height that is greater than the height value, consisting of y1 + 3 xy results and is smaller than the height value, which results from y1 + 4 xy, but is at least so high that the locking element 2 can be converted into a Entarretierstellung. At this height, the force element 205 of the locking mechanism 201 is controlled so that the locking element 202 is screwed into the housing 206 and thereby assumes the Entarretierstellung.

Although in the Fig. 8 An arresting device according to the invention is provided on the laterally displaceable ends of both scissor struts, an arrangement is also conceivable in which only one scissor spar is provided with a locking device, and only one guide is attached to the displaceably mounted end of the other scissor spar. The locking device may optionally be in communication with the upper slidably mounted end of a scissors spar and a running rail, or be in communication between the lower laterally displaceable end of a scissor spar and a foundation.

The Fig. 9A shows a representation of the detent element 100 in a side view. During the initial height y1, the locking mechanism 201 is located in a first portion 102 in which the locking element is engageable with detents 204 having substantially equal distances from each other. When the lift is lifted above an initial value y1, the locking mechanism is located in a second portion 103 in which the pitch the locking elements, that is, the distances between two adjacent detents 204, steadily increase in the longitudinal direction of the detent element 100.

For better presentation shows Fig. 9B an enlarged section of the second portion 103 of the detent element 100. Clearly visible are the increasing longitudinally distances between two notches by the length values xn + 1, xn + 2, xn + 3.

The division, ie the distance between two notches, x _n (n) for n = 1 .... m results from the following formula: $$x_n\left(n\right)=L_0-\left[\sqrt{{l_{\mathit{poor}}}^2-{\left[{\mathrm{<figure-callout\; id="1"\; label="y"\; filenames="imgf0006.png,imgf0007.png"\; state="\{\{state\}\}">y</figure-callout>}}_1+\left(n\cdot y\right)\right]}^2}\right]-\left[L_0-\left[\sqrt{{l_{\mathit{poor}}}^2-\left[{\mathrm{<figure-callout\; id="1"\; label="y"\; filenames="imgf0006.png,imgf0007.png"\; state="\{\{state\}\}">y</figure-callout>}}_1+{\left[\left(n-1\right)<figure-callout\; id="2"\; label="\cdot \; y"\; filenames="imgf0006.png,imgf0007.png"\; state="\{\{state\}\}">\cdot \; </figure-callout>y\right]}^2\right]}\right]\right]\mathrm{,}$$

Here, I _arm corresponds to the length of a scissor bar, the scissor lift, y1 of an initial height and y the fixed predefined distance between the locking positions. L ₀ denotes the position of the first stop, which again results as a function of the starting height y1 from the following formula: $$L_0=\sqrt{{l_{\mathit{poor}}}^2-{{\mathrm{<figure-callout\; id="1"\; label="y"\; filenames="imgf0006.png,imgf0007.png"\; state="\{\{state\}\}">y</figure-callout>}}_1}^2}\mathrm{,}$$

The invention is not limited to the illustrated embodiment. For example, the operation of the tooth claws can be done not only by pressure cylinder, but also by other drive units, such as electromagnetic or purely mechanical drives. Furthermore, the locking of the upper ends of a scissor spar on the running rail not only by positive locking elements, but also by friction, for example by turning cams, moving wedges, etc., take place. The one in the preceding mentioned features and exemplified embodiments of the present invention may be combined in part or in whole with each other as desired, to form further embodiments, which are adapted to corresponding applications of the invention. Insofar as such embodiments result for a person skilled in the art from the abovementioned exemplary embodiments, these are to be regarded as implicitly disclosed with the abovementioned exemplary embodiments.

Claims (14)

1. A scissor-type lifting platform, in particular for vehicles, comprising:

   - stationary support rails (1) on or in a floor level,

   - at least two scissor arms (12, 13; 20, 21) which cross each other and are retained and guided with their bottom ends in the support rails (1),

   - a hinge connecting the two scissor arms (12, 13; 20, 21) approximately centrally to each other,

   - a lifting assembly (11) engaging the scissor arms (12, 13; 20, 21) for spreading and contracting the scissor arms (12, 13; 20, 21),

   - at least one travel rail (28) which includes contact areas (29, 30) and is supported on the top ends of the scissor arms (12, 13; 20, 21),

   - wherein one of the scissor arms (12, 13; 20, 21) is connected to a travel rail (28) with its top end in hinged manner and the other scissor arm (12, 13; 20, 21) is guided on the travel rail (28) with its top end in longitudinally displaceable manner upon the lifting and lowering movement of the scissor-type lifting platform, and

   - wherein the longitudinally displaceable ends of the two scissor arms (12, 13; 20, 21) can be arrested with the associated travel rail (28) at least in the lifted position,
   characterized in that
   an arresting mechanism is hinged at the top and/or bottom end of the one scissor arm which includes a slide element (46, 47) longitudinally guided on the profiled travel rail (28) and at least one locking element (42, 43) which can be arrested on the travel rail (28) or the guide rail (15, 16) in form-locking or force-locking manner, wherein the locking element (42, 43) is hingedly supported in a housing (45).
2. The scissor-type lifting platform according to claim 1,
   characterized in that
   the arresting mechanism (26) includes front and rear slide elements (46, 47) guided inside the profiled travel rail (28) as well as front and rear collectively operable locking elements (42, 43) and the longitudinally displaceable end of the scissor arm is hinged on the centre portion of the arresting mechanism (26) approximately symmetrically between the slide elements (46, 47) and the locking elements (42, 43).
3. The scissor-type lifting platform according to any one of preceding claims 1 or 2,
   characterized in that
   the locking elements (42, 43) are collectively operable by a drive (67, 68).
4. The scissor-type lifting platform according to claim 3,
   characterized in that
   the drive is an electric, mechanic or fluidic drive.
5. The scissor-type lifting platform according to claim 3 or 4,
   characterized in that
   the drive (67, 68) is attached to a front end of a housing (45), on which the slide elements (46, 47), the locking elements (42, 43) and in the centre portion a support bearing (81) for the crossbolt (25) are provided.
6. The scissor-type lifting platform according to any one of the preceding claims,
   characterized in that
   the locking elements (42, 43) are tooth members hingedly supported in a common housing (45) which engage with recesses (39) of toothed racks (38) attached to the respective travel rail in form-locking manner upon swing-out.
7. The scissor-type lifting platform according to any one of the preceding claims,
   characterized in that
   a toothed rack (38) is attached to each sidewall (34) of each travel rail (28) and the longitudinally displaceable ends of the scissor arms (12, 13; 20, 21) are centrally supported in the associated arresting mechanism (26).
8. The scissor-type lifting platform according to any one of the preceding claims,
   characterized in that
   an arresting mechanism (201) is hinged on the top and/or bottom end of a scissor arm which includes a locking element (202) that can be arrested on the travel rail (15, 16) in form-locking and/or force-locking manner, and further comprising a catch element (100), wherein the catch element (100) includes a plurality of substantially similarly formed catches (204), and the locking element (202) can be engaged with at least one catch (204) in detachable, form-locking and/or force-locking manner in a plurality of predetermined catching positions, wherein at least a first catching position, a second catching position and a third catching position can be approached by the locking element (202) in at least a partial region of the catch element (100), wherein at least a first distance between the first catching position and the second catching position and a second distance between the second catching position and the third catching position have different lengths.
9. The scissor-type lifting platform according to claim 8,
   characterized in that
   the catch element (100) includes a first partial region (102), in which the first distance between adjacent catches (204) and the second distance between two adjacent catches (204) are the same, and includes a second partial region (103), in which the first distance between two adjacent catches (204) and the second distance between two adjacent catches (204) are different, wherein the length values of the distances between each two adjacent catches (204) in the longitudinal direction of the catch element (100) increase or decrease.
10. The scissor-type lifting platform according to any one of claims 8 or 9,
    characterized in that
    with increasing lifting height of the lifting platform, substantially in a vertical direction, the pitch of the catch element (100) increases substantially in horizontal direction.
11. The scissor-type lifting platform according to any one of preceding claims 8, 9 or 10,
    characterized in that
    a guide unit (104) is provided which is connected to the catch element (100) such that the locking element (202) can be engaged with the catch element (100) exclusively in predetermined positions.
12. The scissor-type lifting platform according to any one of preceding claims 8, 9, 10 or 11,
    characterized in that
    the guide unit (104) includes an outer contour (105) and the locking element (202) includes an operating means (106) which can be brought into contact with the contour (105) of the guide unit (104) in predetermined positions, whereby contact between the locking element (202) and the catch element (100) can be prevented in these positions.
13. The scissor-type lifting platform according to any one of the preceding claims, comprising a controller (107), characterized in that
    the controller (107) controls the lifting assembly (109) during a lifting operation such that the travel rail (28) reaches a first predetermined lifting height by a lifting movement, and after reaching the first predetermined lifting height, it reaches a second predetermined lifting height by a lowering movement.
14. The scissor-type lifting platform according to claim 13,
    characterized in that
    after reaching the first predetermined lifting height and during reaching the second predetermined lifting height, the force element (205) of the arresting mechanism (201) can be controlled by the controller (107) such that the locking element (202) can be engaged with the toothed rack (100) in form-locking and/or force-locking manner.

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