EP1953113A2 - Multi-column hoisting platform for vehicles - Google Patents

Abstract

The method involves movably and vertically supporting and setting driving rails (3a, 3b) at lifting columns (1a-1d), by form-fitting engagement in vertical retaining elements (5a, 5b) at a desired level. Ratchets (6a, 6b) are directly or indirectly supported at the driving rails in the retaining elements. The ratchets are released or activated by snap movement of the ratchets during setting of the driving rails. The snap movement is monitored and a stroke movement is stopped after snapping the ratchets. The setting of the driving rails is triggered.

Description

The invention relates to a method and apparatus for leveling the rails of a motor vehicle lift with at least two lifting columns on which the rails are mounted vertically movable and by positive engagement in vertically successive holding elements in the desired height deductible by the rails directly or Snap indirectly mounted pawls into the retaining elements.

Such lifts are known with two or four lifting columns in different variants. The rails are usually hydraulically (also on pull cables, chains or the like), but also moved electrically by threaded spindles.

If such lifts are to be used for the axle measurement of vehicles, it is important that the two rails are absolutely horizontal and level aligned, because the rails in this case sliding and / or rotary plates, so that the vehicle wheels, at least the front wheels, stress-free , With an inclination of one of the rails, the vehicle could therefore slip sideways, because the sliding and / or rotary plates are mounted extremely low friction on the rails.

Although most lifts with four lifting columns are used for wheel alignment. Nevertheless, it is problematic to guarantee exactly the same height at all four suspension points of the two rails. That's why we are currently doing so that the already existing safety pawls and holding elements that are intended to prevent sagging of the rails in case of malfunction, used to sell the rails on the stationary support elements. This guarantees a defined height position on all four lifting columns.

Investigations by the applicant have shown that this settling of the rails on the stationary holding elements - generally toothed racks - but sometimes leads to different height positions. The reason for this is the fact that it may happen when activating the pawls that one or two pawls are just above their corresponding holding element, ie above a tooth of the rack, while other pawls are just below their corresponding tooth. Then the discontinuation of the rails leads to different height positions at the four suspension points.

This risk is particularly great when the lifting movement takes place at the four pillars via a common cable drive, because the four ropes running to the individual pillars have different lengths and accordingly also different strains.

If it comes to the described settling of the rails at different height levels, the lift must be raised again and tried to approach a level at the top of the tooth pitch, so that all four pawls are in the same pitch. This requires high attention, additional time and represents a significant security risk if not observed.

Proceeding from this, the object of the present invention is to improve the known multi-column lift to the effect that their rails occupy an absolutely level same height position when weaning. It should be dispensed with readjustments and other additional measures, so that the lift is characterized by easy-to-use and speedy operation.

This object is achieved in that the pawls are not activated or released as previously when stopping or lowering the rails in the sense of Einschnappbewegung, but already at startup of the rails and that the snap-in movement of the pawls is monitored and only after snapping all pawls stopped the lifting movement and the discontinuation of the rails is initiated.

The invention is based on the finding that during the lifting of the rails, the differences in lift between the individual suspension points are still relatively low and only then become a problem when the rails are sold on different high breakpoints, because the pawls in the trip once in a upper, the other times have penetrated into a lower retaining element. This condition is eliminated in the present invention, because the rails after the release of the pawls still a little start up and during this boot the position of the pawls is monitored. As a result, the pawls, which have not yet reached the positive engagement and would cause the discontinuation of the rails an inadmissible slope, are still raised to the appropriate engagement position. While this startup, the already correctly positioned pawls are taken, but still remain in engagement with the correct tooth gap. The controller then detects that all four pawls are snapped in, stops the lifting movement and initiates the landing of the rails.

The only requirement for snapping into level holding elements is that the stroke differences between the individual columns during startup are smaller than the spacing of the holding elements or as the tooth pitch; this is easy to follow.

In this way, can ensure a level snaps and settling of the rails without any additional effort.

For the monitoring of the snap-in movement of the pawls offer the expert various possibilities. This can be detected mechanically, optically or electronically.

It is particularly useful to connect the pawls and / or the holding elements at the same time to a security system that triggers the automatic engagement of the pawls in case of failure of a lifting column. Numerous lifting columns are already equipped with such a security system. In this case, to realize the invention, it is only necessary to realize the monitoring of the snap-in movement and the corresponding control of the lifting movement by appropriate software.

To monitor the pawl position, it is recommended that they are in operative connection with a switching element and this switching element responds upon engagement of the pawls in the holding elements. The signals of the switching elements are transmitted to a control unit, which then, when all switching elements indicate the snap action, stops the lifting movement and instead triggers the settling movement.

Suitably, the pawls are still in operative connection with another switching element which responds in the retracted passive position of the pawls. These signals are also transmitted to a control, so that the shutdown of the lift (not the discontinuation of the rails) takes place only when the lock is released by the pawls.

There are also numerous possibilities for the design of the retaining elements. It may be the already mentioned toothed racks. Instead, but also perforated strips or other constructions with consecutive vertically successive attacks come into consideration. It should be noted in principle that the height difference between adjacent holding elements is at least 3 mm, preferably at least 5 mm, that is, this height difference must be greater than the theoretically possible during the lifting movement of the rails stroke difference between the individual lifting columns.

Figur 1

ein Schrägbild einer Vier-Säulen-Hebebühne;

Figur 2

eine vergrößerte Frontalansicht auf einen Querträger zur Aufnahme der Fahrschienen mit den zugehörigen Halteelementen;

Figur 3

eine Ausschnittvergrößerung des Querträgers im Bereich der Sperrklinke in formschlüssigem Eingriff mit dem zugehörigen Halteelement;

Figur 4

einen ähnlichen Ausschnitt wie Figur 3, jedoch in Schrägansicht und in nicht arretiertem Zustand.

Further features and advantages of the invention will become apparent from the following description of an embodiment and from the drawing; shows

FIG. 1

an oblique view of a four-post lift;

FIG. 2

an enlarged frontal view of a cross member for receiving the rails with the associated holding elements;

FIG. 3

an enlarged detail of the cross member in the region of the pawl in positive engagement with the associated holding element;

FIG. 4

a similar section as FIG. 3 , but in an oblique view and in an unlocked state.

According to FIG. 1 the lift consists of four lifting columns 1 a, 1 b, 1 c and 1 d. At the front lifting columns 1 a and 1 b, a front cross member 2 a, at the rear lifting columns 1 c and 1 d, a rear cross member 2 b are each mounted vertically adjustable. All lifting columns have a known linear actuator for the two cross members, so that they can be moved simultaneously up and down.

On the cross members are mounted in a known manner from front to rear running rails 3a and 3b, which serve to receive the vehicle. These rails are at least in the front wheels with sliding and / or rotary plates 4a and 4b equipped so that the wheels can move in a horizontal force-free position, which is a prerequisite for accurate wheel alignment. Another requirement is to bring the four suspension points for the cross member 2a and 2b at the same height level. For this purpose, the rails or the cross members 2a and 2b carrying them are equipped with a special pawl mechanism, which will be discussed in more detail below.

FIG. 2 shows the latch construction at the two ends of the cross member. In the exemplary embodiment, one sees the front cross member 2a, wherein the lifting columns 1a and 1b arranged at its two ends have been omitted are. As a result, one recognizes holding elements 5a and 5b in the form of vertical perforated strips. These perforated strips are expediently integrated into the lifting columns. They are designed such that they can accommodate a multiple of the vehicle weight.

In addition one recognizes in FIG. 2 in that pawls 6a and 6b are movably mounted on both ends of the crossbeam, in such a way that they can be pivoted from a retracted passive position into an active front position in which they are positively locked to the retaining elements 5a or 5a, as shown in the drawing 5b engage, so that the cross members and the rails held by them on the holding elements 5a and 5b can be discontinued. The associated structural design results from the Figures 3 and 4 ,

Both figures show the right end of the cross member 2a, the associated holding element 5b and the corresponding pawl 6b.

The retaining element 5b consists of a profiled rail which, on its side facing the cross member 2a, has a multiplicity of windows 5b 'arranged vertically one above the other, each being separated from one another by solid intermediate pieces 5b.The cross member 2a can be set down on each of these intermediate pieces.

Furthermore, it can be seen that the pawl 6b is pivotally mounted on the cross member 2a via a horizontal pivot axis 7 in the direction of the holding element 5b.

The pawl 6b is connected via an eyelet 6b 'hingedly connected to a lever 9 which is actuated by an electromagnet 10.

The magnet 10 is loaded by a spring in the locking direction, that is, in the drawing to the right. This ensures that, for example, in a power failure, the pawls are loaded in the locking direction, so penetrate into one of the window 5b 'of the holding element and can prevent a fall of the cross member.

In addition, the pawls are in operative connection with the lifting drive to ensure, for example, in case of leakage in hydraulic lifting drive or in the case of a cable break in a lifting drive by means of ropes that the pawls are operated independently of the voltage applied to the magnet in the locking sense.

When starting up the lift, the individual pawls are deflected by the angled lower ends of the spacers 5b "inward, so swung out of the window 5b 'so that they do not hinder the lifting movement, but in the event of a fall can immediately snap back into the next window.

One can relax in the Figures 3 and 4 easily imagine that when lifting the stage individual pawls have just passed the upper edge of an intermediate piece 5b ", while other pawls can not do so, because they are positioned slightly lower.A discontinuation of the rails then leads to the not yet engaged pawls to a further lowering movement to the next lower window and thus to an undesirable inclination of the rails.

In order to eliminate this risk, the position of the pawls 6b is monitored, in the exemplary embodiment in each case by a switch 11 which is actuated by a pivot arm 9a connected to the lever 9 when the pawl is engaged in one of the windows 5b '. Only when all four switches 11 indicate the latched position of the pawls during startup of the lift, the lifting movement is stopped, because then it is ensured that all pawls are locked in level windows. Then the settling movement can be initiated so that the in FIG. 3 shown state is reached.

FIG. 4 shows the same section as FIG. 3 However, here is the pawl 6b is not engaged with the associated holding element 5b, but at an intermediate height between two windows 5b '. The pawl 6b is loaded in the sense of engagement, but abuts with its front nose on one of the intermediate pieces 5b "on Locking sense can be done by the magnet 10, but instead also by springs, such as a mounted on the axis 7 spring 8 or a differently positioned spring element.

FIG. 4 So shows the state in which the crossbars still need to be raised slightly until finally all pawls are engaged in their associated retaining element. Only then does the lowering begin, so that the transverse members are no longer supported by the lifting elements but by the retaining elements.

Of course, the four holding elements must be aligned with each other so that their respective intermediate pieces 5b "are each at the same level.

A locking pawls in different height window 5b 'is excluded by the fact that the distance between the spacers 5b "(more precisely, its supporting upper edge) is greater than the worst case occurring stroke difference between the four points of articulation of the crossbeams.

Furthermore, the show Figures 3 and 4 in that the pivot lever 9a still cooperates with a further switch 12, specifically when the magnet is in its retracted position, that is to say the pawl is in the unlocked position. If this is true for all four switches 12, the lift can be moved to the lower rest position.

Finally shows FIG. 4 the combination of pawls in a lifting drive via ropes 14. In this known rope drive the crossbars are suspended from cables that are laid to the upper ends of the lifting columns. In this case, the pawls can each be in operative connection with Seilabtastern 13. This Seilabtaster 13 are with their free end to the streamlined rope. If the rope 14 - as is known - is fixed at the upper end of the lifting column and is pulled or issued by a arranged on the cross-beam cylinder / piston unit, the Seilabtaster 13 may have a rotatably mounted roller 13 a, with which they Glide rope along. It is essential that the cable scanner 13 then, if the rope 14 is not taut, give way and can act on the pawl in the locking sense. For this purpose, the scanner 13 may be acted upon by the same spring 8 in the locking direction and are positively engaged with the pawl. At the in FIG. 4 shown section pivots so the pawl 13 in a clockwise direction and takes the pawl 6b with.

In summary, the invention thus offers the advantage that the rails can be leveled and set to the same height, without additional operating effort would be necessary. The operator only needs to press a certain release button, so that the pawls are passively released or actively loaded in the sense of snap action, whereupon the further process (monitoring the pawl position by the switch 11 and settling after reaching the positive engagement on all pawls) is performed automatically ,

Claims (12)

Method for leveling the rails of a lift at the same level with at least two lifting columns (1a-1d) on which the rails (3a, 3b) are mounted so as to be vertically displaceable and can be lowered to the desired height by positive engagement in vertically successive holding elements (5a, 5b), by snapping directly or indirectly mounted pawls (6a, 6b) into the holding elements (5a, 5b) on the rails,
characterized,
in that the pawls (6a, 6b) are already released or activated during the raising of the running rails (3a, 3b) in such a way that the snap-in movement of the pawls (6a, 6b) is monitored and that the lifting movement is stopped only after all pawls have been snapped into place and the landing of the rails (3a, 3b) is initiated. Method according to claim 1,
characterized,
that the snapping action of the pawls (6a, 6b) is mechanically, optically or electronically monitored. Method according to claim 1,
characterized,
that the pawls (6a, 6b) and / or the holding elements (5a, 5b) are simultaneously connected to a safety system, which in case of failure of a lifting column, the automatic engagement of at least the locking pawl (6a, 6b) triggers associated with the lifting column in question. Method according to claim 3,
characterized,
that, for the suspension of the running rails (3a, 3b) on ropes (14), the security system will respond to the cable tension and in case of decreasing cable tension automatic engagement of at least the associated locking pawl (6a, 6b) triggers. Device for leveling off the rails (3a, 3b) of a lift with at least two lifting columns (1a - 1d) on which the rails (3a, 3b) mounted vertically movable and by positive engagement in vertically successive holding elements (5a, 5b) in the desired height are deducted by directly or indirectly mounted pawls (6a, 6b) snap into the holding elements (5a, 5b) on the rails, in particular for carrying out the method according to claim 1,
characterized,
that when starting up the rails (3a, 3b), a release or activation of the pawls (6a, 6b) takes place in the sense of the snapping action that the snapping action of the pawls (6a, 6b) is monitored and that the stopping and drop rails only after the snapping all pawls (6a, 6b) takes place. Device according to claim 5,
characterized,
in that the pawls (6b) are in operative connection with a switching element (11) and this switching element (11) responds when the pawls engage in the holding elements (5b). Device according to claim 5,
characterized,
that the pawls (6b) are in operative connection with a further switching element (12) and this switching element (12) in the unlocked position of the pawls (6b) responds. Device according to claim 5,
characterized,
that the holding elements (5b) by the lifting columns (1a - 1d) are arranged racks, perforated strips or the like. Device according to claim 5,
characterized,
that the vertical distance between adjacent holding elements (5b ") of at least 5 mm, preferably at least 10 mm. Device according to claim 5,
characterized,
that when suspension of the rails (3a, 3b) on ropes (14), the pawls (6a, 6b) are in operative connection with the ropes (14) and are actuated with decreasing cable tension in the sense of their engagement movement. Device according to claim 10,
characterized,
that the actuation of the pawls (6a, 6b) is carried by springs (8). Device according to claim 10,
characterized,
in that the pawls (6a, 6b) are in communication with cable scrapers (13).

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