WO1999040406A1

WO1999040406A1 - Auxiliary apparatus for handling car wheels in connection with wheel or tyre servicing

Info

Publication number: WO1999040406A1
Application number: PCT/DK1999/000060
Authority: WO
Inventors: Arne Hjort-Hansen
Original assignee: Hjort Hansen Arne
Priority date: 1998-02-09
Filing date: 1999-02-09
Publication date: 1999-08-12
Also published as: AU2265999A; DE19982877T1

Abstract

For the balancing of serviced vehicle wheels it is known to use a wheel lifter, by means of which the wheel can be raised from ground level to a level, in which the wheel, standing on a displaceable sledge, is insertable onto the rotation spindle of a balancing machine. The raising height is rather short, and the invention provides for a wheel lifter with such an increased lifting height that is is usable even for the lifting of the wheel sufficiently for the wheel to be laid down on the rotary table of a tyre changer machine placed next to the balancing machine, as well as for receiving the serviced wheel and bringing it down to the mounting position at the balancing spindle. The wheel is supported on a carrier plate which at the high lift may collide with parts of the balancing machine, but according to the invention the carrier plate and its associated support is arranged entirely outside the side limitation, only with the carrier plate being displaceable for bringing the downloaded wheel to the balancing spindle in being supported by a projectable telescopic system, which in its normal position is located substantially entirely underneath the carrier plate.

Description

Auxiliary apparatus for handling car wheels in connection with wheel or tyre servicing

The present invention concerns an ancillary unit for use primarily in the handling of vehicle wheels in connection with wheel or tyre servicing. In connection with the repair or changing of tyres, it is widespread work-shop practice for the work to be effected with two different types of apparatus, i.e. a tyre-changing machine and a balancing machine, each of which constitutes an independent unit without any form of integration. The tyre-changing unit normally has a circular, rotary plate which lies horizontally at normal working height, and upon which the wheels are placed in the lying position. The balancing unit has a spindle which ex- tends horizontally and which normally lies at the same height as said circular, rotary plate.

It is and has for many years been quite normal practice for the wheel handling in general to be carried out in a purely manual manner, in that the wheels are lifted up to and down from the rotary plate, and from here up to and down from the balancing spindle. This situation has not been changed despite the fact that more advanced systems have been developed which, for use in special concerns, are configured with various ancillary equipment such as roller tracks for easing the handling of the wheels .

A second hereby known and here more relevant ancillary unit is disclosed in WO 95/30617, i.e. a wheel lifting unit which by means of a compressed-air cylinder can raise or lower a wheel from a. low or respectively slightly raised initial level to a level which is suitable for the mounting and removal of the wheel on and from the spindle of the balancing unit. This intermediate level is "floating", in that the air cylinder is con- nected to a larger pressure tank so that the wheel is supported underneath by air springs, whereby the operator can quite easily press the wheel slightly up and down for precise adjustment of said spindle with the wheel in the 2

"weightless" state. The cylinder piston rod supports a rail guide for an upright, horizontally-displaceable support slide for the wheel, whereby the wheel placed on the slide can easily be displaced inwards and outwards over the spindle. The relevant rail guide can well be used in connection with completely free-standing balancing machines, where a maximum lifting height of up to approx. 15 cm will normally be sufficient, whereas with greater lifting height the rail guide can collide with parts of the balancing machine.

A variant of such a lifting and transfer unit is disclosed in US-A-5,603, 148, where the variation consists in said rail guide being configured as a fixed floor installation in a machine line, in that the lifting unit is placed in a displaceable manner along this rail and thus merely requires to support a relatively small support plate for a wheel standing hereon. However, it will continue to apply that the elongated rail guide, despite the fact that it is now mounted on the floor, will generally be inconvenient if it is used for the transfer of wheels directly between the two relevant units, and moreover in this connection there is also a relatively low lifting height involved. However, in US-A-5,603 this is not the case, in that the wheel is received from an outgoing rol- ler track from a preceding inflation station. It is here^¬ by necessary for the lying wheels to be turned for correct mounting on the balancing spindle, which is effected by tipping each wheel delivered down in a V-shaped support, in which the operator can tip the wheel over to the opposite inclination, and from here by combined pushing- up and further tipping bring the top of the wheel for laying down on the said support plate, now with the wheel turned 180°. From this position, the wheel is tipped up to the upright position on the support plate, after which the wheel, now turned through 270° on the support plate, can be pushed directly over to the balancing spindle.

With the present invention, an alternative and advantageous solution is provided, i.e. with a column part 3

from which there extends a support arm which is adjustable in height along the column, and which at its free end has a transversely inwards and outwards displaceable support for a wheel carrier plate, i.e. preferably a scissor-like or telescopic structure which in retracted state lies substantially in under the carrier plate. There can hereby be achieved a desirably great degree of displacement of the carrier plate, completely without the use of the said rail guide, and the displacement struc- ture will only be distinctly space-demanding in connection with the actual transferring of wheels to the balancing machine, where the work is anyway concentrated at the front end of the projected structure. This can be of such small inherent height that it can bring the carrier plate quite closely in against the front of the balancing unit, i.e. bring a wheel standing on the carrier plate completely in over the balancing spindle, and without any of the potential collision problems which could otherwise arise . This ancillary unit can be placed directly at the side of the wheel -changing unit, whereby it can also be used for lifting the wheels up to the said rotary plate, as well as for receiving the wheels from here for the transfer to the balancing machine, and finally for lower- ing the wheels to floor level. The balancing unit can thus be placed directly opposite the other side of the carrier plate, so that with the high lift this can move completely free of the parts of the balancing unit, while at a lower height the carrier plate can still be pushed over to its wheel -supporting position completely in under the balancing spindle. In arrangement and control, the lifting means used can to a wide extent be as disclosed in the above-mentioned WO 95/30617, though with the possibility of a certain simplification which is described in more detail below.

When a wheel is to be delivered from the rotary plate of the tyre changing unit to the said carrier plate, this can be effected in a simple manner in that the wheel, which is lying on the plate, is pushed out from the rotary plate until it tilts down around the edge of the plate for tipping down on to the raised carrier plate, on which it is then easily raised to its standing position. This corresponds to one of the three 90° tipping movements which are used in US-A-5 , 603 , 148 , but in order to achieve the remaining two part-turns of 90°, it will now be a simple possibility for the wheel standing on the carrier plate to be turned 180° around its vertical axis, after which the wheel is ready to be transferred to the balancing spindle. It is hereby a special feature of the invention that the carrier plate can be provided with a small, easily-running rotary table, which will make it possible for the turning of the wheel to be carried out in a quite simple manner, and which is preferably dish- shaped for the stabilising of the wheel in its standing position .

It will be understood that the lifting apparatus must be able to receive the wheels with these standing in a plane parallel with the vertical plane through said support arm, and that this arm must therefore extend so far out from the fixed column part that there will be the necessary free space to accommodate a wheel of the anticipated greatest diameter. In the following, the invention will be explained in more detail with reference to the drawing, in which

Fig. 1 is a schematic perspective view of a workstation with an ancillary unit according to the invention, Fig. 2 is a plan view of the same, Fig. 3 is a perspective view of an ancillary unit according to the invention, and

Fig. 4 is a schematic diagram of the control by compressed air of a pressure cylinder in the ancillary unit. In Fig. 1 there is shown a conventional tyre changing unit 2 which at its right-hand side is configured with a support area for a standing wheel 4 with the view to the pressing of the tyre bead away from the edge of the wheel rim by means of a pressure tool 6 on a movable arm 8 ex- tending from the unit. Thereafter, it is normal for the operator to manually lift the wheel up on to an upper, horizontal rotary table 10, on which the tyre bead can be levered out over the edge of the rim by means of a tool, a so-called tyre lever 12, on a fixed column 14. Upon completion of the repair or tyre change, the wheel is lifted down from the rotary table 10, traditionally in a manual manner, in that it is then rolled on the floor over to the second main unit 16, which is a wheel balanc- ing unit with a horizontally-extending wheel spindle 18. The wheel is lifted up on this spindle where it is fastened, after which the balancing work is effected by and during rotation of the wheel, which is then unfastened and lifted down from the spindle 18, ready for remount - ing on the vehicle.

In accordance with the invention, there are two units 2 and 16 placed precisely in the positions shown, i.e. with a relatively short distance between them and with the spindle 18 facing directly towards the tyre changing unit 2, such as also shown in Fig. 2. Opposite the space between the two units, there is placed an ancillary unit 20 according to the invention, this unit having a column with a horizontally-extending support arm 22 which projects into said space and has a carrier plate 24 for a standing wheel. This plate can be raised and lowered by means of an air cylinder 26 in the unit 20, i.e. it can be used to raise a wheel which is rolled from the bead- breaking station with the tool 6 and rolled up onto the plate 24, from a position directly over the floor to an upper position in which the wheel can be brought into a lying position on the rotary table 10. It will be seen that the plate 24 can hereby move freely past the balancing spindle 18 and possibly an under edge of an ordinarily appearing wheel guard 17. In this position, the plate 24 can thus also receive the wheel when the service on this has been completed, in that the wheel is merely pushed out from the rotary table and swung to the upright position on the plate 24. The raising of the plate 24 can 6

be effected and controlled by means of an operating valve 19 which controls the supply of compres-sed air to the lower part of the cylinder, in that the valve is closed or opened as soon as the plate 24 reaches its upper level. This will require a little longer activation time, in that the heavier the wheel the longer the activation time. It is important that there is not more compressed air introduced than the plate just manages to reach to or directly under the upper position. As shown in Fig. 1, the raising and lowering of the support arm is preferably carried out via a pulley system 27.

When from the raised position the wheel is laid down on the rotary table 10, the carrier plate system which is loaded herewith will be pressed up against a not-shown upper end stop because of the now surplus air pressure in the cylinder 26, but the situation will be restored when the wheel is later brought back to the carrier plate 24.

Hereafter, the task of the ancillary unit is to lower the carrier plate 24 to a level at which the centre of the wheel lies opposite the balancing spindle 18, and to enable such a displacement of the hereby "intermediately- lowered" wheel so that this can be introduced over the spindle without the operator having to exert any effort in the supporting of the wheel. Here it must be taken in- to consideration that not all wheels are of the same diameter, i.e. some standardised intermediate position will normally be involved. It could well be envisaged that use is made of an operator-controlled evacuation of the cylinder 26, so that a lowering will be able to be arranged precisely to the relevant desired level, but with the invention it is a preferred possibility that the work is hereby effected with a floating level, whereby the wheel is supported in such a manner that it appears "weightless", i.e. a level at which the operator can easily push the wheel slightly up or down for adjustment of the wheel to the correct height for the mounting on the spindle 18. It is herewith that the above-mentioned air spring enters the picture. 7

This air spring, which can be realised by connecting the lower end of the cylinder 26 to a larger air tank 28, see also Fig. 3, has earlier been suggested in a relevant context as a means of achieving a "weightless" wheel when this is to be mounted on the spindle 18, and thus to achieve a precisely-centred tightening of the wheel on this spindle, cf . WO 95/30617, but hereby not as a means for the positioning of larger or smaller wheels at a correct mounting level. With reference to the same publica- tion, use is made of special control means in order to enable any wheel received to be raised or lowered to the "weightless" area, but with the present invention it has been found sufficient to work with a simplified system, whereby the wheel is raised to this area in an operator- controlled manner.

In that the compressed-air pressure is not greater than the carrier plate is just brought precisely into the upper position, it will hereby be possible for the operator to lower the wheel to the relevant intermediate level by a simple manual depression of the support system, since there will hereby occur only a slight build-up of the pressure in the air spring system. The upright wheel which is pushed off the rotary table 10 will naturally stand on a support area 30 of the plate 24 which is transversely oriented in relation to the direction of the balancing spindle 18, i.e. it will be immediately ready for introduction over this spindle after having been brought to the relevant level .

To enable this introduction over the spindle to be effected in a simple manner, the carrier plate 24 is mounted on the support arm 22 via a telescopic system, which is shown in more detail in fig. 3. The arm 22 supports a fixed plate 32 on which a pair of cylinders 34 are mounted horizontally, and which have displaceable te- lescopic elements 36 and 38. The outer ends of the elements 38 are provided with support pieces 40 which secure the carrier plate 24 in a slightly raised position in which it is otherwise freely suspended and extends rear- 8

wards over the telescopic system. In this way it is possible to feed a wheel 4 standing on the plate 24 right in to its mounting position on the spindle 18, while at the same time the associated telescopic system also at its opposite end will normally lie completely in underneath the carrier plate 24, and in a manner in which it requires very little space, and which precisely for this reason can be used in a position closely up against the wheel changer 2. Thereafter, to enable a completely free balancing rotation of the wheel on the spindle 18, the carrier plate 24 must be displaced in the downwards direction. It will be obvious that this can be done in different ways for the temporary releasing of the wheel, but with the inven- tion there is the preferred possibility for the raising system to be pressed to the bottom by supplying compressed air at the full pressure to the top of the cylinder 26, whereby the effect of the underlying air spring will be overcome without the air volume of the spring or its spring potential being otherwise changed in any way.

Such a depression can be expediently controlled by means of a pedal actuator 21, which upon first depression is arranged to establish an open connection between the supply of compressed air and the top of the cylinder 26, entirely in accordance with said WO 95/30617.

With the carrier plate pressed down to its bottom position, the wheel 4 can thus be freely rotated on the spindle 18, and when the balancing operation has hereby been completed, there will remain the task of supporting the wheel during its withdrawal from the spindle 18 and subsequent lowering to floor level. To achieve this, the control system is arranged in such a way that a subsequent activation of the control pedal 21 will cause a closing of the compressed-air supply to the top of the cylinder 26 as well as an evacuation of the cylinder, so that the said air spring can now become fully effective again, i.e. for the raising of the carrier plate 24 into support contact against the wheel now released from the 9

spindle 18. The wheel can thus be drawn free from this spindle by reversed activation of the telescopic system, cf . Fig. 2, though preferably merely by a simple manual withdrawal thereof. Thereafter, the task will be to get the released wheel lowered to the floor position. Consequently, the pedal actuator is arranged in such a manner that another subsequent activation will again result in a supply of compressed air to the top of the cylinder 26, so that the plate 24, now together with the wheel, will be pressed to the bottom and remain in this position when the wheel is rolled out from the plate. This will hereby be ready to receive the next wheel .

If or when the next wheel is of more-or-less the same weight as the preceding wheel, the filling of air which arises in the air spring system will already be suitable, and a renewed pressure on the pedal will give rise to a relieving of the downwards pressure on the support system, so that the wheel will immediately be raised to the relevant top position.

It can be expedient for an indicator to be provided, such as a red lamp, which indicates the fact that there is air pressure on the top of the cylinder 26, so that an operator does not mistakenly believe that a bottom posi- tion of the system is due to a lack of air pressure in the air spring system.

If the next wheel is heavier or lighter, the operator must carry out a corresponding adjustment of the air spring pressure by means of the valve 19 in order to get the plate raised to the correct uppermost or "almost uppermost" position.

As shown in fig. 4, the valve 19 can have three operating positions, i.e. a middlemost, closed position, a lower position for the supply of compressed air to the bottom end of the cylinder 26 and herewith to the tank 28, and an upper position in which the valve opens for evacuation from the relevant space. The pedal activator 21 can be a pneumatic or an electric changeover switch, 10

which upon each activation alternates respectively between the changing of a control valve 23 between compressed air supply to the top of the cylinder 26 and evacuation of this cylinder. With the course of operations described, the wheel which is delivered from the rotary table 10 will lie "valve-side" up to enable it to be inflated. When the wheel is raised by being tipped up on the plate 24, the wheel will hereby stand in reversed position in relation to the position necessary for mounting on the balancing spindle 18, i.e. the wheel must be turned 180°. This can be done manually, but with the invention, however, it has been found to be a great relief for the operator if the said receiving area 30 is configured a disk which can easily be turned. This can also be of a dish-shaped configuration, whereby at the same time it will stabilise the wheel in its rolling direction, which contributes towards a very easy turning movement of the wheel. What is preferably involved is a simple, uniform depression in the plate, whereby this is also able to hold the wheel upright even though it is released.

Claims

C L A I M S

1. Ancillary unit for use in the handling of vehicle wheels in connection with wheel or tyre servicing, where use is made of a tyre changing unit with rotary table and a balancing unit with wheel supporting spindle which stand in close relationship with said ancillary unit, in that said ancillary unit, which is intended to occupy a fixed position of use between the two said units, has a support column with a projecting support arm which is displaceable in height and on which there is provided a carrier plate suitable for the supporting of an upright wheel, said support column having a lifting arrangement which can be activated for the raising or lowering of the support arm between a position near the floor and an upper position at almost the same level as said rotary table, and where said carrier plate is arranged in such a manner that it can be displaced sufficiently in the sideways direction that a wheel supplied to and standing hereon can be displaced to a mounting position at an intermediate mounting level for mounting on said wheel support spindle, c h a r c t e r i z e d in that the carrier plate is supported on the support arm by means of a horizontally-extendible and retractable system, prefer- ably of the scissors-mechanism or telescopic type, which is arranged in such a manner that in the retracted position it lies substantially entirely within the end limitations of the carrier plate, i.e. at that end facing towards the tyre changing unit.

2. Ancillary unit according to claim 1, c h a r a c er i z e d in that said lifting arrangement is of the type which comprises a compressed-air cylinder with a large effective air volume so that it serves as an air spring, thus enabling easy manual adjustment of the height of the carrier plate for bringing wheels of dif-ferent diameters to a centred level in relation to the balancing spindle.

3. Ancillary unit according to claim 1, c h a r a ct e r i z e d in that the displacement system consists 12

of a two-part telescopic system which at its outer ends is connected to the front end of the carrier plate, this being effected in such a way that when the system is retracted, the plate can be withdrawn to a position in which it lies over and above the telescopic system in general .

4. Ancillary unit according to claim 1, c h a r a ct e r i z e d in that the carrier plate is provided with a rotary table for the support of a wheel standing up- right on the carrier plate and which can easily be turned .

5. Ancillary unit according to claim 4, c h a r a ct e r i z e d in that the rotary table is dish- or saucer-shaped for stabilising the wheel in the upright posi- tion.