AU2019204369B2

AU2019204369B2 - Parking device for motor vehicles

Info

Publication number: AU2019204369B2
Application number: AU2019204369A
Authority: AU
Inventors: Martin Baeurle; Norbert Faessler
Original assignee: Klaus Multiparking GmbH
Current assignee: Klaus Multiparking GmbH
Priority date: 2014-02-04
Filing date: 2019-06-21
Publication date: 2021-04-01
Anticipated expiration: 2035-02-04
Also published as: EP3102757B1; AU2019204369A1; WO2015118034A1; EP3102757A1; DE102015100132A1; AU2015214938A1

Abstract

The invention relates to a parking device (1) for motor vehicles (19) comprising at least one platform (10, 11) that can be raised and lowered and that carries the at least one motor vehicle to be parked. The platform is situated between at least two hydraulic cylinders (30, 30'), which can be supplied with a volume of hydraulic fluid under pressure, and is connected to the extendable elements of the hydraulic cylinder, the motion of the extendable elements causing the platform to be raised and lowered. A tilt sensor (4) is provided on the platform. Said sensor measures the angle of inclination of the platform to the longitudinal axis of said platform. The value of the angle of inclination is fed continuously to a control device (5). The control device regulates the pump drive (33) on the basis of a comparison with a reference value. - 32 1/3 6 500, u un u LFL1 - - --30 5 3 -- 54 .- 38 30231 312 304-30 41 32 3332

Description

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Parking device for motor vehicles

The invention relates to a parking device for motor vehicles comprising at least one platform that can be raised and lowered and that carries the at least one motor vehicle to be parked, and the platform is situated between at least two hydraulic cylinders, which can be supplied with a volume of hydraulic fluid under pressure, a hydraulic pump supplies the hydraulic fluid with pressure, and the platform is connected to the extendable elements of the hydraulic cylinders, the motion of the extendable elements causing the platform to be raised and lowered.

Furthermore, the invention relates to a retrofit kit or the use of a control device, in particular in the event of retrofitting, of a parking device for motor vehicle, wherein the parking device has at least one platform that can be raised or lowered by a drive, and the invention also relates to a method for moving the platform(s) of a parking device.

The parking devices described in the introduction are well known. They are to be found for example as stacking or double parkers in underground garages etc. and have the advantage that more than only one vehicle can be parked on a base area. Known parking devices consist of a supporting structure, on which the at least one platform can be raised or lowered. At least two hydraulic cylinders are provided, for example, as the drive for the raising or lowering movement of the platform, wherein the platform or platforms is/are situated between the two hydraulic cylinders. The platform(s) is/are mounted so as to be guided in the supporting structure. It should be noted that this platform/these platforms has/have to bear the weight of one, two or even more vehicles and a tilting of the platform(s) in the vertically oriented guides is unfavorable, since this can prejudice the usability of the parking device and/or can damage the parking device itself.

However, a plurality of different drives for aforementioned parking devices are also known in the prior art. Thus for example chain or cable hoists driven by electric motors are known, which likewise cause the platforms to be raised or lowered.

The requirements for generic parking device are considerable. On the one hand, they should be produced very cost-effectively, but at the same time they should have a long service life. Even if these are installed in underground garages or covered parking places, the generic parking devices are also subject to corrosion, since in the winter spray and salt water affect the platforms, which inevitably leads to corrosion. Also in principle it is not simple in structural terms to use advantageous elements to raise and lower heavy loads without judder, i.e. at the same speed on all elements (for example supports) of the support structure. However, malfunctions of the synchronized running lead to corresponding mechanical stresses, such as friction or other wear.

Starting from this prior art, the object of the present invention is to improve a parting device in such a way that its sustainability, i.e. its long-term usability, is significantly improved over an extended period of time.

Any references to documents that are made in this specification are not intended to be an admission that the information contained in those documents form part of the common general knowledge known to a person skilled in the field of the invention, unless explicitly stated as such.

Throughout the specification and claims, unless the context requires otherwise, the word "comprise" or variations such as "comprises" or "comprising", will be understood to imply the inclusion of a stated integer or group of integers but not the exclusion of any other integer or group of integers.

In order to achieve this object, the invention is based on a parking device as described in the introduction and proposes that a tilt sensor which measures the angle of inclination of the platform about the longitudinal axis of the platform is arranged on the platform, and the value of the angle of inclination is supplied to a control device and the control device compares the measured value of the angle of inclination with a reference value, and the control device is, on the one hand, electrically connected to the pump drive of the hydraulic pump and/or, on the other hand, co operates by means of respective control lines with valves arranged in the hydraulic feed lines of the hydraulic cylinders, and, clocked by a control frequency, as a function of the comparison between reference value and measured angle of inclination, acts on the pump drive and/or the valves, the control device changing the control frequency or the opening width of the valves as a function of the change in the angle of inclination over time.

2A

Therewith, it is an advantage of the invention that the control device is, on the one hand, electrically connected to the pump drive of the hydraulic cylinder and/or, on the other hand, co operates with valves arranged in the hydraulic feed lines of the hydraulic cylinders. The invention is designed so integrally that both simultaneously, and also in a simple configuration of the invention, only the pump drive alone or the valves alone are influenced by the control device.

Therewith, the invention also covers different strategies for reacting to the changes of the angle of inclination, and therefore it is not contradictory that the control device changes the control frequency or the opening width of the valves as a function of the angle of inclination and/or as a function of the change of the angle of inclination over time. In simpler strategies, control takes place only as a function of the angle of inclination or only as a function of the change of the angle of inclination over time. In higher-level scenarios both criteria are utilized.

The object according to the invention is also achieved in the same way by a retrofit kit for parking devices for motor vehicles, consisting of a tilt sensor which is or can be connected by means of a measuring line to a control device and at least one control device equipped with a control line provided at the output end, wherein the parking device has at least one platform that can be raised or lowered by a drive and, in the event of retrofitting the tilt sensor can be fastened the platform in such a way that the tilt sensor can measure the angle of inclination of the platform about the longitudinal axis of the platform, and the value of the angle of inclination can be or is supplied to the control device, and that in the event of retrofitting the control device compares the measured angle of inclination with a maximum angle of inclination, and the control line of the control device can be connected to the drive in such a way that in the event that the angle of inclination exceeds the maximum angle of inclination the drive is switched off.

Furthermore, the object according to the invention is achieved, in particular in the event of retrofitting, by the use of a tilt sensor which is or can be connected by means of a measuring line to a control device and at least one control device equipped with a control line provided at the output end, for parking devices for motor vehicles, wherein the parking device has at least one platform that can be raised or lowered by a drive and, in the event of retrofitting the tilt sensor can be fastened the platform in such a way that the tilt sensor can measure the angle of inclination of the platform about the longitudinal axis of the platform, and the value of the angle of inclination can be or is supplied to the control device, and that in the event of retrofitting the control device compares the measured angle of inclination with a maximum angle of inclination, and the control line of the control device can be connected to the drive in such a way that in the event that the angle of inclination exceeds the maximum angle of inclination the drive is switched off.

The crux of the invention is that it has been recognized that, by the use of position information and the temporal change of this position information which is obtained via the tilt sensor and control or regulating information derived therefrom, the mechanical loading and, as is described in detail in relation to the method also forming part of the invention, also the risk of corrosion are significantly reduced. The proposal according to the invention convincingly achieves the object described in the introduction of attaining an improvement in the long-term performance of the generic parking device. It can be used in a great variety of ways and in particular can also be implemented in existing parking devices, as is described in the context of the likewise claimed retrofit kit or the use in the event of retrofitting.

In a preferred embodiment it is provided that the value of the angle of inclination is supplied continuously to a control device and the control device continuously compares the measured value of the angle of inclination with a reference value. In this case "continuously" means that the transmission of the measured values and the control process initiated thereby take place regularly, with an adjustable time period, and thus a permanently uniformly smooth operation of the platform is achieved.

In this case in an advantageous manner the tilt sensor is arranged on the underside of the platform, that is to say it is protected by the platform itself. It is connected to the control device for example by means of a wired line or by a wireless link.

In an advantageous embodiment of the invention it is provided that the result of the movement of the platform is monitored, that is to say a control/regulating circuit is used and the actual movement, in particular the inclination the platform, is recognized and is taken into consideration for regulating purposes.

This is achieved in that a tilt sensor is arranged (at least) on a platform. The tilt sensor senses the angle of inclination of the platform about the usually horizontal longitudinal axis of the platform. In this case the longitudinal axis of the platform is usually oriented parallel or substantially parallel to the longitudinal extent of the vehicle parked thereon. Provided that the angle of inclination in the horizontal (this would then be oriented at right angles to the longitudinal axis) in the ideal case is the smallest possible, that is to say 00, an angle of inclination greater than 0° already presents a certain risk of tilting of the platform in the parking device with the problems described above. This twisting is discovered by the use of the tilt sensor, since the angle of inclination is continuously supplied to the control device. A reference value is stored in the control device, and the control device continuously compares the measured value with the reference value. The reference value is for example an angle which is tolerable in structural terms, i.e. within which there is no risk of tilting. It is derived for example from the generally necessary tolerances which are usual for the construction of such parking devices. If the tilt sensor now detects an angle of inclination which is not tolerable (because it is greater than the reference angle, corresponding to a malfunction), then the control device intervenes in a suitable manner in the drive of the platform.

The drive is usually provided by two hydraulic cylinders, with at least one valve arranged in each case in the hydraulic feed lines. The hydraulic cylinders are operated with hydraulic medium pressurized by a pump drive. The control device is connected, for example, to the valves and/or the at least one pump drive in such a way that in the event of a malfunction it opens or closes the valves or throttles or increases the pump drive. The object of these measures is to position the platform again so that the angle of inclination is smaller than the reference angle. This can take place, for example, by braking on one side (for example the side running at a higher speed) or by accelerating the side which is lagging behind, that is to say it is inclined downwards. Since the users of the parking devices in question generally want to reach the vehicles parked on the platform as quickly as possible, the platform is regularly braked on one side in the event of a malfunction, in order to regain the horizontal orientation, but the invention is in no way limited to this. In this case the arrangement is selected so that the result of a corresponding controlling measure is monitored and also evaluated again.

A significant advantage of the embodiment of the invention is in particular that with the proposed arrangement the synchronization characteristics of these parking devices is considerably improved. The generic parking devices are in particular faced with the problem that the drives provided on both sides of the platform, usually hydraulic cylinders, raise or lower the respective side of the platform in the same way, i.e. in particular at the same speed. It is clear that a number of sources of disruption can prejudice the desired synchronized operation, however by means of the proposal according to the invention the actual position of the platform itself, i.e. the inclination, is determined and in the event that there is no synchronization this leads to an angle of inclination different from 0°, which is initially tolerable within a tolerance range (up to the reference value) but beyond that is intolerable, and which is then corrected again by suitable measures.

A further advantage of the solution according to the invention over the prior art is that the control of the synchronization of the platform takes place according to the invention as a function of the angle of inclination. A large angle of inclination of the platform represents a greater risk of tilting than a smaller angle of inclination. Control as a function of the angle of inclination should be understood to mean that with a larger angle of inclination the countermeasures initiated by the controller are greater or stronger than with a smaller angle of inclination. Thus, for example, with a greater angle of inclination the inflow of hydraulic oil to the hydraulic cylinder which is located on the side which lags behind, is increased to a greater extent than with a smaller angle of inclination. Thus the parking device according to the invention adapts its control to the respective current inclination of the platform and as a result, more quickly and more efficiently, it again produces an angle of inclination of the platform within the tolerance. This control of the synchronization of the movement of the platform is always adapted precisely to the current requirements and therefore constitutes a substantial improvement with respect to the durability of the parking device but also the convenience when using the device.

The solution according to the invention is particularly advantageous in that in addition to the information about the current angle of inclination of the platform of the parking device, as described in the preceding paragraph, the temporal change of this current angle of inclination can also be included in the control of the synchronization. The use of this change of the angle of inclination over time as input into the automatic control of the synchronization of the platform leads to an even quicker and more efficient control. If, for example, a quick change of the angle of inclination, in other words a substantial temporal change of the angle of inclination, is ascertained, the action to counteract the inclination of the platform is accordingly controlled more strongly than would be the case with a small temporal change of the angle of inclination. In the case of a substantial change of the angle of inclination, for example, the inflow of hydraulic oil to the hydraulic cylinder of the side which lags behind is correspondingly increased proportionally to the magnitude of the change of the angle of inclination over time. Thus a quick change of the angle of inclination is met with a correspondingly quick acting, efficient countermeasure. As a result, the production of an angle of inclination within the tolerance range is achieved more quickly than would be possible with a control without taking account of the temporal change of the angle of inclination over time. If, then, after a substantial temporal change of the angle of inclination with a correspondingly initiated quick countermeasure a smaller temporal change of the angle of inclination is again measured, accordingly the countermeasure, for example the inflow of hydraulic oil on one side of the platform, is also slowed down or reduced again. As a result, the risk of over-controlling the angle of inclination of the platform into the opposite direction is substantially reduced. Thus the use of the temporal change of the angle of inclination as input information also serves for control in order to reduce the number of control loops until an angle of inclination of the platform which is within the tolerance is restored. Thus according to the invention the described use of the temporal derivation of the angle of inclination contributes to a substantial improvement of the control speed and control quality for a uniform movement of the platform of a parking device.

In the prior art proposals for synchronization monitoring are known, these are implemented for example by torsion rods which are gripped transversely by means of the platform. The proposal according to the invention avoids these torsion rods and saves weight, without changing the stability of the parking device. Furthermore, by the proposal according to the invention a substantially more sensitive, i.e. more judder-free, synchronization monitoring is implemented than with the known mechanical elements. The proposal according to the invention considerably improves the energy efficiency of the parking device equipped in this way. The judder-free synchronization reduces friction losses which were to be compensated for by increased energy input on the lifting means. The maximum required hydraulic pressure can also be reduced, since the torsion rods also led to pressure losses in the hydraulic system.

Thus the proposal according to the invention is limited not only to a reduction in terms of mass and thus also in terms of cost, but leads to a more careful and more energy-efficient operation of the parking device and thus to a sustained and long lasting, much less high maintenance product.

Therewith the control device recognizes, on the basis of the plus/minus sign of the angle of inclination, which side is running ahead and which side is lagging behind. Now (and this is the preferred variant) the side which is running ahead can be braked, for which purpose for example the solenoid valves or valves provided in the hydraulic feed line are closed briefly and thus are separated from the hydraulic pressure and volumetric flow of the hydraulic fluid. Alternatively, it is of course also possible to somewhat accelerate the side which is lagging behind and thus to achieve a horizontal position again.

Within the context of this application it makes no difference whether the parking device has one platform or a plurality of platforms which is/are provided to receive motor vehicles. If the term "platform" is used in the singular or plural, this does not exclude the use of the proposal on a platform in the plural or singular.

Furthermore. the invention proposes a retrofit kit or the use of elements provided in some circumstances on the parking device, such as a control device and a tilt sensor, in particular in the event of retrofitting. Also with this proposal the object described in the introduction is convincingly achieved, since thus it is also possible to control the movement of the platforms, in particular the monitoring thereof. In this case it is deliberately provided that this embodiment of the invention is designed as a retrofit kit or as a use in the event of retrofitting, and thus also existing parking devices, irrespective of the specific configuration of their lifting and/or lowering drive for the platform, can participate in the advantages of the invention.

In the prior art parking devices are known, in which the platforms are driven in a substantially simpler manner, as in the case described above. In this case often only one lifting means, for example a hydraulic cylinder is provided, which is arranged on one side on the parking device and which by means of suitable solutions (for example chain hoists) transmits the lifting force. In this case monitoring of the synchronization is likewise problematic. For older parking devices, by the application of the retrofit kit proposed according to the invention or the use thereof (optionally in the event of retrofitting) a considerable improvement in the operational safety is achieved. In this case the proposal according to the invention achieves a reliable monitoring of the movement of the platform(s), specifically because with it an oblique position of the platform, that is to say a position of the platform outside the tolerable range of angles of inclination, leads to switching off of the drive of the parking device. As a result, the risk is averted, that the parking device is damaged due to the unwanted malfunction or, in the worst case, the vehicle parked on the platform is damaged. The solution described here for achieving the object set out in the introduction remains deliberately open with regard to the configuration of the drive, since in addition to hydraulic lifting means naturally any other motor-driven lifting means can be employed, for example cable winches, cable hoists, etc.

The proposal according to the invention discussed here has at least three different possible embodiments:

First of all, it is provided that this embodiment is employed as a retrofit kit on existing parking devices.

In the second case a parking device which is already equipped with corresponding elements is used as described. In this case then this does not involve an upgrade at a later stage in the event of retrofitting, but an additionally original characteristic.

In the third case the existing arrangement of the parking device is actually retrofitted by the use as described, i.e. is upgraded at a later stage.

Since the use claim chosen here is assigned to the category of method claims, the applicant explicitly reserves the right to claim this configuration also in the context of a method.

It is provided that the drive is switched off if the angle of inclination exceeds a maximum angle of inclination. Such a situation can be provided as an emergency shutdown. The emergency shutdown is then preceded by a call for maintenance in which the parking device thus equipped, used or retrofitted still remains operational, but maintenance is recommended (this recommendation is output for example on a display device which is connected to the control device) and so safe operation is ensured.

This proposal according to the invention describes at least three different phases or uses or operational states. In the first operational state, the normal mode, the measured angle of inclination smaller than a first critical angle. In the second operational state, the call for maintenance, the measured angle of inclination lies between the first critical angle and the maximum angle of inclination. The third operational state, the emergency shutdown, is characterized in that the measured angle of inclination is greater than the maximum angle of inclination. This sub-division of the operational states described here can also be described or claimed by a method for operating or moving the platforms of a parking device.

The approaches to a solution which are described above relate to control of the movement of the platform so that a safe and disruption-free operation, associated with careful operation of the parking device, is possible. The aim here is to move the platform with the smallest possible angle of inclination in order to avoid the problems described above. However, the approach according to the invention is not limited thereto. A contribution to the conservation of resources is also provided if the known parking devices are operable so that damaging influences are reduced or eliminated.

Therefore the proposed solution also comprises a method for the controlled inclination of at least one platform, which can be raised or lowered, of a parking device for motor vehicles, wherein the platform is arranged between two lifting means each driven by a drive means, a tilt sensor is provided on the platform, and the tilt sensor is connected to a control device, wherein before the start of the inclination the platform is located in a defined position, the control device predetermines a maximum inclination reference value, and the control device acts via control lines on the drive or elements (for example valves) of the drive of the lifting means in such a way that the required inclination reference value is reached, the tilt sensor continuously measures the angle of inclination and passes it on to the control device, where the angle of inclination is continuously compared with the inclination reference value and, when the inclination reference value is reached, the control device switches off the drive(s) of the lifting means.

The method proposed according to the invention is employed for example in order to deliberately incline the platform in order to allow any water on the platforms (for example waste water, salt water, etc.) to run off. In principle the platforms are equipped to prevent corrosion with corresponding protective equipment (coatings, etc.). The long-term performance and thus also the lasting value of parking devices operated according to the invention are considerably increased if water located on the platform can run off as quickly as possible and therefore it is not even possible for corrosion to occur. In this case the proposal according to the invention deliberately exploits the idea of the invention, namely the monitored controlled movement of the platform, in particular the inclination thereof.

Thus it is provided, for example, that the parking device equipped in this way regularly carries out corresponding maintenance runs, that is to say it tilts the platform by a few degrees so that water located on the platform can run off. This can then be provided when the parking device is empty, that is to say no vehicle is parked. However, in principle it can also be carried out with parked vehicles.

In this connection the term "drive" should be interpreted very broadly. The drive is designed, for example, as a central drive, which supplies a plurality of lifting means with operating pressure or with lifting power, and the drive then also includes elements (of the drive) which enable control on the respective lifting means. These elements include, for example, valves, that is to say electromagnetically controlled hydraulic valves, which are arranged in the feed line, but other elements can also be provided, such as for example gears, etc., depending upon the configuration of the drive. In so far as in this claim reference is made to drives in the plural, this means, for example, a discrete drive assembly for each lifting means (that is to say on each side of the platform), but also the arrangement of a central drive which co-operates with the elements associated with the respective lifting means.

Furthermore, in the invention it is advantageously provided that the control device controls the valves with a control frequency with pulse width modulation, and as a function of the angle of inclination it controls the pulse width and, as a result, the opening or closing times of the valves. As is also described in particular in connection with Figure 1, the arrangement is chosen so that a valve which is controlled by the control device is arranged in the hydraulic feed line before the hydraulic cylinder. These valves are equipped, for example, as switching valves, which ultimately have two switching states, namely open and closed. If 100% volumetric flow is required, then the valve must be temporarily closed for a period of time. Therefore, such a valve is supplied with a control frequency, wherein a 100% opening of the valve correspond to 100% activation of the valve within the control period defined by the control frequency. If the volumetric flow is to be limited, then within the control period the valve is temporarily closed, which is commonly done by means of pulse width modulation. It has been found that such a procedure enables a very sensible and therefore also effective possibility for control, precisely in order to achieve high-quality synchronization.

In this case control of the valve(s) takes place by, for example, increasing the pulse width, that is to say the opening time of the valve is increased, if the control device recognizes that the platform is inclined. An increase in the volumetric flow is then indicated, for example, on the side that is lagging behind. Conversely, it may be advantageous for the side that is running ahead to be braked a little, by reducing the pulse width a little there and thus the valve is closed proportionately more when considered over a time period.

Instead of a switching valve it is also possible to employ proportional valves, which are equipped with an electromagnetically controlled proportional magnet, and which enable an adjustable opening width of the valve passageway according to the control. Such a solution also forms part of the invention.

An advantageous embodiment of the invention provides that the control device comprises at least one controller and a memory, the memory stores a characteristic field of characteristics, from which, at least as a function of the sensor signal of a sensor, in particular the tilt sensor, a characteristic is selected from the memory in a selector unit and is passed to the regulator. Furthermore, this embodiment improves the control for the synchronization of the platform of a parking device. In order to adapt the control to the respective current situation a selector unit is provided here which, depending upon the situation, selects the best suited characteristic and passes it to the controller for control. At least one sensor signal is used as input information for the selection of this currently best suited characteristic. In the simplest case the signal of the tilt sensor is employed for this purpose. Then, on the basis of the current angle of inclination and/or the current temporal change of this angle of inclination, the selector unit selects the best suited characteristic from a characteristic field stored in a memory. As has already been described above, when a large angle of inclination is present, for example, a characteristic is selected which effects a quick and robust countermeasure against the present large inclination of the platform and thus ensures a quick restoration of an angle of inclination within the tolerance. Accordingly, at a smaller angle of inclination a characteristic for a less robust countermeasure is selected in order to achieve the same objective, namely an angle of inclination within the tolerance.

A characteristic should be understood here to mean the functional relationship between two variables. An electric voltage is used, for example, for activation of a proportional valve which controls the flow of hydraulic oil to a cylinder. Thus the control device uses a voltage signal as output to such a proportional valve. A characteristic for the control of such a proportional valve could, for example, be the functional relationship between the electric voltage for the proportional valve as a first variable and the time as a second variable. Such a characteristic describes the progression of the voltage during the control. However, the invention also covers any other functional correlations between two variables such as, for example, the change of an electric current intensity a first variable and the time as a second magnitude. Furthermore, correlations of manipulated variables such as, for example, voltage or current intensity as first variable over a path as second variable, are conceivable. Current information relating to such a path could be made available by an additional path sensor, the signals of which likewise enter the selector unit for selection of a characteristic. It would likewise be possible to use information on the quantity of the flowing hydraulic oil into a cylinder as a second variable for a characteristic. Information on the current flow of the hydraulic oil can be communicated by means of a flow sensor to the selector unit of the control device. To summarize, the characteristics used in this proposal can be functional correlations between the most varied physical variables.

Various such characteristics are stored in a characteristic field. In addition to the actual characteristics which constitute a functional relationship between two variables, further parameters relating to these characteristics are stored in this characteristic field. The selector unit compares these stored parameters with the parameters present in the current situation. Thus, for example, the currently measured angle of inclination is compared with the angles of inclination stored in the characteristic field as parameters. The selector unit then selects the dividing line of which the stored parameter for the angle of inclination best matches the currently measured angle of inclination. Since according to the invention a selection of the characteristics is possible not only with reference to one parameter but a plurality of parameters can be included in the selection of a characteristic, this is referred to as a multi dimensional characteristic field. The characteristics stored in this characteristic field can be determined in advance empirically by experiments. However, it is also possible for characteristics produced or determined in some other way to be stored there.

Such control is implemented, for example, by corresponding regulation or control software. Alternatively, it is possible to use a neural network for this.

It is advantageously provided that in addition to the at least one tilt sensor at least one sensor for measuring the pressure of the hydraulic oil and/or at least one temperature sensor and/or at least one sensor for measuring the flow of hydraulic oil are provided and also the sensor signals of these additional sensors act on the selection of the current characteristic from the characteristic field. As described in the preceding paragraph, it is possible for the signals of various other sensors to be included in the selection of the current characteristic.

A variant of the invention offers the possibility of implementing a characteristic field control. The control device has two parameters which it can influence, namely both the pulse width modulation within the control period, in order to open or close the valves, and also the control frequency itself. Depending upon the operating parameters or operating processes, that is to say the temporal change of the angle of inclination, in particular when corresponding countermeasures are initiated, it is provided in the controller or the control device that the control frequency is then also changed if required. For this purpose, advantageously only the information of the tilt sensor, optionally the temporal change thereof, is required, and with these two parameters it is already sufficient to control the characteristic field defined by the pulse width and the control frequency. Naturally it is possible, for this control of characteristic values, also to take account of further parameters, such as for example the height of the platform, or the power consumption of the pump drives, etc.

In an improved embodiment it is provided that the control device does not only modulate the pulse width, but the control device changes the control frequency as a function of the angle of inclination or as a function of the temporal change of the angle of inclination. If on the basis of the change of the angle of inclination the control device recognizes that, at the control frequency set in principle, the provided pulse width modulation is not sufficient in order to achieve judder-free synchronization, the control frequency is increased, which does lead to increased stress on the valves or the switching valve, but treats the parking device as a whole with care. In this case the control device not only awaits the result of the measurement of the tilt sensor, but, if required, the temporal derivation, i.e. the temporal change of the angle of inclination, is optionally also used. Thus, for example, a change of the control frequency will be considered when a first measure, namely a reduction of the pulse width, has not led to a reduction of the angle of inclination. Obviously then the control period is too long, and it is then advisable, by quicker control, that is to say a shorter control period, to restore the required horizontal position of the platform.

Furthermore, it is provided that a volumetric flow measuring device is arranged before each hydraulic cylinder in the hydraulic feed line, each of said measuring devices being connected by means of a measuring line to the control device, and by means of the continuous measurement of the volumetric flow the control device infers the current height of the platform. With the height information it is possible to brake the platform in its raising or lowering movement just before its end position is reached, which is achieved by a change of the pulse width on the switching valves. It is clear that the height of the platform can also be determined equivalently in the same way by a separate sensor, and this height information is then likewise fed into the control device by this height sensor.

In an advantageous embodiment it is provided that the control device controls the pump drive on the basis of the ascertained height the platform and/or on the basis of the measured angle of inclination. Ultimately the hydraulic volumetric flow flowing into and out of the hydraulic cylinder is responsible for the raising or lowering movement of the platform. In order to control the movement of the platform it is necessary to control this volumetric flow. This can take place not only by activation of the valves provided in the hydraulic feed lines, but also the pump drive is activated appropriately. Advantageously a pump drive is provided if the individual volumetric flow takes place by means of the two valves, which are each associated with a hydraulic cylinder. In principle, however, it is also possible -- and this solution is also covered by this invention -- that each hydraulic cylinder has its own pump drive which is controlled.

In an advantageous manner it is provided that a central hydraulic pump driven by the pump drive is provided, and a branch to the hydraulic cylinder is provided in the hydraulic feed line after the hydraulic pump, in particular after the pressure reservoir, and a safety valve controlled by the control device is arranged between the hydraulic pump and the branch. Due to the safety valve it is possible to decouple the hydraulic circuit of the hydraulic cylinder from the pump and the storage container provided for the hydraulic fluid. The safety valve is, for example, closed in emergencies, so that no hydraulic fluid can flow back out of the hydraulic cylinders and thus a lowering movement is prevented.

In this case the invention also additionally comprises strategies with further parameters (height of the platform, measured angle of inclination (a)), with which the pump drive or the valves, which also complement one another, or can each be used individually, are controlled.

In a further preferred embodiment it is provided that the control device has an indicator, in particular an acoustic, optical or plain text indicator, or is connected to an indicator, in particular an acoustic, optical or a plain text indicator, by means of a data line, and the control device outputs status and/or error information about the parking device by means of the indicator.

In a further embodiment of the invention it is provided that at least two tilt sensors are arranged on different areas of the platform, and each determine the angle of inclination of the respective platform area about a longitudinal axis of the platform and supply it to the control device. A first advantage of the provision of a plurality of tilt sensors is the increases reliability of the parking device. In the event of damage or failure of a tilt sensor, it is still possible to operate it by means of the signals of the other tilt sensor(s). Furthermore, by means of the use of a plurality of inclination signals it is possible to detect flexing of the platform of the parking device. When only one tilt sensor is used there is the risk that flexing of the platform, such as can occur in the event of loading with heavy vehicles, is erroneously interpreted as inclination of the platform. In the event of interpretation as inclination a corresponding counter-control would then be triggered during synchronization, which in reality is not even necessary. The use of two tilt sensors makes it possible here for flexing to be recognized and not to be interpreted as inclination. Depending upon the installation position of the at least two tilt sensors on different areas of the platform, flexing along the longitudinal axis or the transverse axis of the platform can be detected. The longitudinal axis or transverse axis of the platform correspond respectively to the arrangement direction or the entry/exit direction of the parked vehicles. Thus flexing caused both by vehicles of different weights and also by vehicles which are not correctly positioned in the entry/exit direction are recognized. Of course it is also possible to mount a plurality of tilt sensors, for example four units, on a platform in order to be able to recognize all possible flexing.

Furthermore, it is advantageously provided that, in the event that the measured angle of inclination is greater than a maximum angle of inclination, the control device outputs error information and/or acts on the pump drive, in particular to throttle it. As described, the control device interprets the angle information of the tilt sensor. If an angle occurs here which is borderline or even intolerable, the control device already initiates corresponding measures in order ultimately to achieve a horizontal orientation of the platform again. Simultaneous this operational state can be communicated to the operator by means of the output of corresponding error information. This is even also advantageous for maintenance. It is clear that, depending upon the embodiment of the invention, the control device can not only act on the pump drive but in the same way can also influence the valves.

Here too the proposal has a comprehensive configuration, since depending upon the design of the parking device, several scenarios can be employed. In a simple variant only one item of error information is output, in serious cases the pump drive can be throttled appropriately, and of course the invention also covers a combination of these two complementary proposals.

In a further embodiment of the invention it is provided that a pressure reservoir is provided between the hydraulic pump and the hydraulic cylinder. The control proposed according to the invention is so sensitive that in it the pressure fluctuations of the hydraulic pump trigger control cycles. The hydraulic pump, for example a rotary pump, such as a centrifugal pump or the like, do not exhibit any constant pressure development over time, but have temporal recurring pressure peaks. These pressure peaks lead to corresponding movements of the hydraulic cylinders which, if they occur on one side, are recognized by the tilt sensor. Due to the arrangement of a pressure reservoir between the hydraulic pump and the at least one hydraulic cylinder, the pressure peaks are substantially reduced and a smooth, uniform synchronization is achieved.

The same can also be achieved with pumps which, considered over time, exhibit the most homogeneous pressure development possible, such as for example relatively compact, but high-speed pumps.

Since with the proposal according to the invention the safe operation of the parking device is dependent upon the reliability and correctness of the angle of inclination detected and transmitted by the tilt sensor, it is advantageous in an improved embodiment to provide that the control device has a monitoring module for the plausibility of the measured angle of inclination. An algorithm which monitors the plausibility of the measured angle of inclination can, for example, be implemented in such a way that, on the basis of the speed or the maximum speed of the platform per unit of time, only a maximum change of the angle of inclination can take place. If now the measured angle of inclination exceeds this limit, then in some circumstances no control measure is initiated by the control device. However, in the future in some circumstances maintenance will be recommended, if consequently the tilt sensor also does not supply plausible values.

Furthermore, according to the invention it is advantageously provided that the control device has a calibration module for the adjustment of the zero position of the fitted tilt sensor.

Furthermore, the object according to the invention is achieved by a method for monitoring the angle of inclination of at least one platform, actively situated in an unmoved state, of a parking device, wherein the platform is arranged between two lifting means each driven by a drive, a tilt sensor is provided on the platform, and the tilt sensor is connected to a control device, and by means of control lines the control device acts on the drives or elements (for example valves) of the drives of the lifting means in such a way that when the angle of inclination is exceeded by means of an idle angle of inclination the angle of inclination is reduced again.

The following state should be described here as a platform (or parking device) actively situated in an unmoved state:

A platform (or parking device) actively situated in a moved state would be the normal state of use if a user wishing, for example, to park or collect their vehicle on a parking device moves the platform vertically. The user is active and the platform or the parking device moves.

A platform (or parking device) which is actively situated in an unmoved state differs from a situation in which there is no user present requiring a (preferably vertical or substantially vertical) movement of the parking device and, associated therewith, of the platform. The method proposed according to the invention monitors this unmoved state (described hereafter as the resting mode), and thus is actively in this state.

The hydraulic poppet valves or proportional valves used for control may exhibit a certain leakage in practice. This means that in the closed condition small quantities of hydraulic oil can flow through the valve. If a parking device does not move over a relatively long period of time, for example while the vehicle owner is away on vacation for several weeks, in spite of very slight leakage of a hydraulic valve a significant lowering of one or both sides of the parking device can occur. In this case it is particularly critical if only one hydraulic valve has a leak and thus a substantial inclination of the platform of the parking device occurs in the unmoved state. However, it may also occur that the valves of both hydraulic cylinders have a leak, and the leads may be of the same or different sizes.

In order that no lowering of the parking device on one or two sides can occur in the unmoved state, an idle mode is provided according to the invention. In this idle mode the control device also monitors the angle of inclination as well as the temporal change thereof in the movement-free state of the parking device. If in this case a significant change of angle is ascertained, the control device automatically readjusts, so that no permanent lowering of the parking device occurs. This automatic readjustment takes place in a particularly slow resetting of the relevant hydraulic cylinder, since in the automatic mode no operator is present to monitor the movement of the parking device. In this embodiment it is particularly advantageous that no inclinations of the parking device can occur which are so great that they distort the apparatus so much that damage occurs. Thus the idle mode enables greatly improved availability of the apparatus, even after a relatively long period of disuse.

Hydraulic cylinders are preferably provided as lifting means. The method described above can be advantageously carried out in particular with a parking device, such as is described in the introduction.

In this context it is pointed out in particular that all features and characteristics but also procedures described with regard to the parking device or the retrofit kit are also transferable analogously in relation to the formulation the method according to the invention or the use thereof according to the invention and can be employed in the context of the invention and may be regarded as also disclosed hereby. The same also applies conversely, in other words structural features, i.e. features in apparatus terms, which are only mentioned with regard to the methods or use thereof can also be taken into account and claimed in the context the apparatus claims for the parking device or the retrofit kit, and are likewise included in the disclosure.

In the drawings the invention is illustrated schematically in particular in one exemplary embodiment. In the drawings:

Figure 1 shows a block diagram of the parking device according to the invention,

Figure 2 shows a block diagram of the retrofit kit according to the invention,

Figure 3 shows a block diagram with details of the mode of functioning of the control device according to the invention.

In the drawings the same or corresponding elements are in each case designated by the same reference numerals and therefore are not described again unless this is expedient.

In Figure 1 the parking device 1 according to the invention is illustrated schematically. The parking device 1 is formed by a support structure, for example a supporting frame 12, on which in the exemplary embodiment illustrated here two platforms 10, 11 are arranged movably one above the other. The lifting means or hydraulic cylinders 30, 30' serve for the movability of the platforms 10, 11. The platforms 10, 11 serve to receive and to park motor vehicles 19. In this case the motor vehicles 19 are supported one above the other in the parking device 1. The longitudinal axis of the parking device is perpendicular to the drawing plane, and the vehicles 19 can be seen from the rear here. The parking device 1 has a width which makes it possible to park two motor vehicles 19 alongside one another per platform 10, 11.

The hydraulic cylinders 30, 30' are ultimately an element of the drive 39, or the drive 39 in the exemplary embodiment illustrated here is implemented as a hydraulically acting drive. This hydraulic drive comprises a pump drive 33, which is designed for example as an electric motor and which drives a hydraulic pump 35, for example by means of a drive shaft. In this case the hydraulic pump 35 draws in hydraulic fluid from the storage container 301 in order to guide this via the hydraulic feed line 36 to the hydraulic cylinders 30, 30'. Because of the pressure generated thereby and the volumetric flow from the storage container 301 into the hydraulic cylinders 30, 30', the piston together with the piston rod (as extendable element 32, 32') moves out of the cylinder and raises the element, in this case the platform 10, 11, connected to the piston rod or the cylinder housing. The other element of the hydraulic cylinder, the cylinder housing or the piston rod, is fixedly supported in an abutment.

Since in the exemplary embodiment illustrated here the platforms 10, 11 are arranged between the two hydraulic cylinders 30, 30' it is clear that both hydraulic cylinders 30, 30' are supplied in the same way with hydraulic fluid by the hydraulic pump 35. Therefore, a branch 37, which divides into a first section, the hydraulic feed line 31 to the hydraulic cylinder 30, and a second section, the hydraulic feed line 31' to the hydraulic cylinder 30', is located in the hydraulic feed line 36.

The safety valve 38 which is connected via a control line 55 to the control device 5 is located between the hydraulic pump 35 and the branch 37. The safety valve 38 is, for example, closed when the platforms 10, 11 have reached a raised end position. When the safety valve 38 is closed it is not possible for hydraulic fluid to run out of the hydraulic cylinders 30, 30' via the return line 302 back into the storage container 301. The return line 302 opens into the hydraulic line 36 between the hydraulic pump 35 and the safety valve 38. Downstream of the safety valve 38 the hydraulic line 36 is identified by a double arrow in order to clarify that certain regions of the hydraulic line 36 convey the hydraulic fluid in both directions or the arrows indicate the flow direction of the hydraulic fluid.

A shut-off valve 304 is also located in the return line 302. This is connected to the controller 5 via the control lines 501. This shut-off valve 304 is closed when hydraulic fluid is conveyed from the hydraulic pump 35 into the working cylinder 10, 10'. Otherwise hydraulic fluid would be circulated directly into the storage container 301.

Furthermore, a pressure reservoir 303 is provided in the hydraulic feed line 36. This is located (in the conveying direction of the hydraulic fluid to be checked) after the hydraulic pump 35 and before the safety valve 38. This pressure reservoir 303 has several objectives. Firstly, it provides a volume with a corresponding pressure potential, so that the entire hydraulic apparatus is kept at a permanent pressure. This can be achieved by a corresponding device, for example a hydraulically movable ram, which is weight-loaded.

A further function and a further advantage of the use of the pressure reservoir 303 is that it acts as a buffer for pressure peaks generated by the hydraulic pump. It has been observed that the pressure peaks of the hydraulic pump cause initiation of the control/regulation process, since the controller reacts very sensitively to such changes of position determined by pressure peaks and thus to changes of the angle of inclination.

Adjustable valves 34, 34' are located between the branch 37 and the respective hydraulic cylinders 30, 30' in the hydraulic feed lines 31, 31', just before the hydraulic cylinders 30, 30'. In this case the valves 34, 34' are operatively connected by means of the control lines 50, 50' to the control device 5. A volumetric flow measuring device 300, 300' is provided in each case between the valves 34, 34' and the hydraulic cylinders 30, 30'. The volume (either absolute or per unit of time) flowing into or out of the hydraulic cylinder 30, 30' is measured by the volumetric flow measuring device 300, 300', and this volumetric flow is communicated by means of the measuring line 51, 51'to the control device 5.

The tilt sensor 4 is arranged on the underside of the upper platform 11. For the invention it makes no difference whether the tilt sensor 4 is located on the upper platform 11 or on the lower platform 10, and thus it is also possible that both platforms 10, 11 each have a tilt sensor 4. The purpose of the tilt sensor 4 is to detect an inclination of the platforms 10, 11 about the longitudinal axis (in this case at right angles to drawing plane) and to report it by means of the measuring line 54 to the control device 5. In the preferred horizontal position of the platforms 10, 11, shown here by a solid line, the angle of inclination a = 0°. An angle of inclination a > 0°, which can lead to the problems described above, is indicated by a broken line on the upper platform 11.

The tilt sensor 4 notifies the respective measured angle of inclination a to the control device 5 not only during the movement of the platforms 10, 11 from a first end position to a second end position. The respective end position is also monitored or controllable by a more permanent communication of the angle of inclination from the tilt sensor 4 by means of the measuring line 54 to the control device 5. It is, for example, correlated with the opening time of the safety valve 38, i.e. while the safety valve 38 is open he position or inclination of the platform 10, 11 is continuously monitored by the tilt sensor 4, even when the platforms 10, 11 are not being moved by the drive 39.

If an angle of inclination a > 00 is detected by the tilt sensor 4 and is passed by means of the measuring line 54 to the control device 5, then a situation occurs in the parking device 1 which should actually be corrected, that is to say avoided. A disruption of the synchronization occurs, with the risk of increased wear and also jerking which is unpleasant for the operator. The two valves 34, 34' are operated with pulse width modulation. In this case the valves 34, 34' are operatively connected by means of the control lines 50, 50' to the control device 5. In the incorrect position of the upper platform 11 indicated by a broken line in Figure 1, the right hand part of the platform 11 is lowered a little, the left-hand part of the platform 11 is running a little ahead. It is now appropriate for this part of the platform 11 which is running ahead to be braked a little. This is achieved in that that the control device 5 reduces the pulse width in a suitable manner within the control period of the left-hand valve 34, which is indicated by the left-hand voltage characteristic 500. The right-hand voltage characteristic 500' remains constant. If the two voltage characteristics 500, 500' are compared over time, the left-hand characteristic 500 a temporary switching off, i.e. closing of the switching valves 34, whereas the right-hand valve 34' remains permanently open, since here too the pulse width amounts to 100% of the control period. Due to the temporary closure of the left-hand valve 34, the hydraulic cylinder 30 is temporarily disconnected from the volumetric flow, and a further extension, i.e. lifting, of the left-hand part of the platform 11 is not possible. Since in the same time period the right-hand valve 34' remains open, the entire delivery power of the volumetric flow can enter (right-hand) hydraulic cylinder 30' by means of the valve 34' and there can preferably raise the right-hand part of the platform 11 in order to position the platform 11 as a whole horizontally again.

The indicator 6 is connected to the control device 5 by means of the data line 52. The display 6 shows in a plain text indicator 60 the current state of the parking device 1, in particular the inclination. Control of the parking device 1 is also possible in principle by means of the display 6. For this purpose, for example, the two PLUS and MINUS keys are shown, by which a raising or lowering of the platforms 10, 11 is possible.

In Figure 2, the use of retrofit kit 7 likewise proposed according to the invention in a parking device 1 is shown. In the exemplary embodiment of the retrofit kit 7 illustrated here the retrofit kit 7 consists firstly of the tilt sensor 4, which is connected by means of a measuring line 54 to a control device 5. Furthermore, the retrofit kit 7 also has a control line 53, which can be connected in suitable manner to the drive 39. With the aid of the retrofit kit 7 proposed according to the invention it is possible to equip existing parking devices 1 with effective synchronization monitoring. In this case the tilt sensor 4 is arranged on a platform 10, 11 of the parking device 1 in such a way that the tilt sensor 4 is well protected. This may be, for example, both on the underside and on the top side of the platform 10, 11. The control device , which here is, for example, integrally equipped with an indicator 6, is fitted at a suitable operating position. The indicator 6 displays, for example in plain text, the synchronization state of the parking device 1. If the control device 5 is fitted, the data link between the control device 5 and the tilt sensor 4 is produced by means of the measuring line 54.

The control line 53, which connects the control device 5 to the drive 39, optionally also comprises a switch or a relay at the end in order, for example, to interrupt the current supply of the drive 39.

If such a retrofit kit 7 proposed according to the invention is fitted to an (old) parking device 1, the user of such a parking device 1 obtains the following advantage: due to the fitted tilt sensor 4 the control device 5 recognizes a possible inclination of the platforms 10, 11 about the longitudinal axis of the parking device 1. The tilt sensor 4 notifies this angle of inclination a regularly, i.e. continuously, to the control device 5. If the measured angle of inclination a deviates from a maximum permissible angle of inclination, the drive 39 is ultimately switched off by means of the control line 53.

Figure 3 shows details of the mode of operation of the control device 5 as well as details of the structure and mode of operation of the plain text indicator 60. The mode of operation of the control devices is described below, starting with a signal from the tilt sensor 4.

The tilt sensor 4 continually transmits signals to the control device 5 at defined time intervals. These time intervals are very short and are usually in the region of substantially less than 1 second. The length of these time intervals in which signals are transmitted or the resulting transmission frequency of the tilt sensor 4 can be set within certain limits. In this case the transmission frequency describes the timing with which the signals of the tilt sensor are emitted. The control frequency, on the other hand, describes the timing with which the signals of the control device to the actuators, such as for example the valves of the hydraulic cylinders, are transmitted.

In the control device the signals of the tilt sensor 4 are initially processed by a signal conditioning 75. Thus the current angle of inclination a is determined from the raw signal. Furthermore, the temporal change of the angle of inclination a' is calculated relative to the values transmitted just beforehand for the angle of inclination a. Thus the current angle of inclination a as well as the current changed angle a' are output from the signal conditioning as conditioned output signals of a sensor.

The current angle of inclination a is transmitted as an actual value directly to the actual controller 56 where it is input directly into the control of the parking device.

In addition to the current angle of inclination a the current changed angle a' serves as input into a selector unit 57 for selection of a characteristic for the controller 56. This selector unit

57 first of all determines the difference between the current temporally changed angle a' and a desired value of the changed angle. This desired value is made available by the desired value unit 59. The difference between the actual value and the desired value of the changed angle a' is then the basis for selection of a current characteristic for the controller 56. The difference between the actual value and the desired value of the changed angle a' is compared with values from a characteristic field which is stored in the memory 58. In this case the characteristic best suited to the current desired/actual value difference of the change of the angle of inclination a' is selected from this characteristic field and is transmitted as current characteristic to the controller 56. The characteristic field used has been empirically determined in advance and based on tests in which parameters such as for example temperature, loading of the parking device or duration of operation have been systematically varied.

Thus the control behavior of the controller 56 is influenced by the temporally changed angle a' influenced, as in each case a characteristic adapted to the current temporally changed angle a' is used for control. Although only the signals of the tilt sensor 4 are used as input into the control device 5, by means of the stored characteristic field in combination with the temporally changed angle a' an adapted control of the parking device to various physical characteristics or parameters such as, for example, the oil temperature of the hydraulic system is possible. It is particularly advantageous that no further sensors and inputs into the control device are required for these various physical influencing parameters. Thus a characteristic field experimentally determined once only in advance in combination with only one type of sensor, namely one or more tilt sensors 4, enables a simple and robust structure of the control device for a parking device according to the invention without having to omit any control adapted individually to the respective operational state.

Naturally, further sensors can be additionally connected to the control device 5 and the signals therefrom can be used as inputs for control of the parking device. Figure 3 shows, for example, a temperature sensor 70, a pressure sensor 71 as well as a volumetric flow measuring device 300, 300' for determining the quantity of hydraulic oil flowing. The signals from these sensors are used as inputs into the selector unit 57. Thus it is possible for the selection of the currently used characteristic for control of the parking device also to be influenced or supplemented by currently determined physical parameters. This may further improve the control behavior. The signal of the volumetric flow measuring device 300, 300' is also passed simultaneously to the controller 56 in order thus, for example, also to transmit the height of the platform 10, 11 to the controller.

The respective currently valid desired value for control of the controller 56 is provided by the desired value unit 59. The desired value for the angle of inclination a in normal operation is , since the objective is synchronization without inclination. However, applications are also conceivable where the desired value of the angle of inclination a deliberately increased, for example, to 50 in order to allow accumulated water on the platform to run off. In addition to a desired value for the angle of inclination a, the desired value unit 59 also specifies a current desired value for the temporally changed angle a'. This current desired value for the temporally changed angle a' is provided to the selector unit 57 for the characteristic and is used there for determining the difference between the predetermined and actual value and thus is employed for adapted selection of a characteristic for the controller 56.

The controller 56 then controls the actuating values for the two valves 34, 34' on the basis of a desired value from the desired value unit 59, an actual value for the angle of inclination a from the signal conditioning 75 and a characteristic from the selector unit 57, wherein this selector unit 57 in turn is influenced by the current temporally changed angle a'.

The desired value unit 59 is controlled by the plain text indicator 60 with respect to the desired values for the angle of inclination a and the temporal change of the angle of inclination a'. This plain text indicator 60, which also serves as an input unit, has various input elements which can be used for operation of the parking device.

The claims filed now with the application and later are without prejudice for the achievement of more far-reaching protection.

If closer examination, in particular also of the relevant prior art, reveals that one or the other feature is favorable for the object of the invention, but is not crucially important, then of course a formulation will be sought which no longer includes such a feature, in particular in the main claim. Also such a sub-combination is covered by the disclosure of this application.

It should also be noted that the configurations and variants of the invention described in the various embodiments and illustrated in the drawings can be combined with one another in any way. In this case individual features or a plurality of features are interchangeable with one another in any way. These combinations of features are also disclosed.

For the purposes of the original disclosure it is pointed out that all the features as disclosed for a person skilled in the art by the present description, the drawings and the claims, even if they have been specifically described only in connection with specific further features, can be combined both individually and also in any combination with other features or groups of features disclosed here, so long as this has not been explicitly excluded or does not make technical details of such combination impossible or meaningless. For reasons of brevity and legibility of the description there will be no comprehensive, explicit presentation of all the conceivable combinations of features.

The dependencies set out in the dependent claims refer to the further embodiment of the subject matter of the main claim by the features of the respective subordinate claim. However, these are not to be understood as a renunciation of the achievement of independent objective protection for the features of the dependent subordinate claims.

Features which have only been disclosed in the description or also individual features from claims which include a plurality of features can be incorporated into the independent claim/claims as features of essential significance to the invention in order to distinguish them over the prior art at any time, even when such features have been mentioned in connection with other features or also achieve particularly favorable results in connection with other features.

Claims

1. A parking device for motor vehicles having at least one platform which can be raised or lowered and is provided in order to support the at least one motor vehicle to be parked, and the platform is situated between at least two hydraulic cylinders, which can be supplied with a volume of hydraulic fluid under pressure, a hydraulic pump supplies the hydraulic fluid with pressure, and the platform is connected to the extendable elements of the hydraulic cylinders, the motion of the extendable elements causing the platform to be raised and lowered, and a tilt sensor which measures the angle of inclination of the platform about the longitudinal axis of the platform is arranged on the platform, and the value of the angle of inclination is supplied to a control device and the control device compares the measured value of the angle of inclination with a reference value, and the control device is electrically connected to the pump drive of the hydraulic pump and/or co-operates by means of respective control lines with valves arranged in the hydraulic feed lines of the hydraulic cylinders, and, clocked by a control frequency, depending on the comparison between reference value and measured angle of inclination, acts on the pump drive and/or the valves, wherein the control device changing the control frequency or the opening width of the valves depending on the change in the angle of inclination over time.

2. The parking device according to claim 1, wherein the control device comprises at least one controller and a memory, the memory stores a characteristic field of characteristics, from which, at least depending on the sensor signal of a sensor, in particular the tilt sensor, a characteristic is selected from the memory in a selector unit and is passed to the regulator.

3. The parking device according to one of the preceding claims, wherein the control device has an indicator, in particular an acoustic, optical or plain text indicator, or is connected to an indicator, in particular an acoustic, optical or a plain text indicator, by means of a data line, and the control device outputs status and/or error information about the parking device by means of the indicator.

4. The parking device according to one of the preceding claims, wherein in the event that the measured angle of inclination is greater than a maximum angle of inclination, the control device outputs error information and/or acts on the pump drive, in particular to throttle it.

5. The parking device according to one of the preceding claims, wherein a pressure reservoir is provided between the hydraulic pump and the hydraulic cylinder.

6. The parking device according to one of the preceding claims, wherein a volumetric flow measuring device is arranged before each hydraulic cylinder in the hydraulic feed line, each of said measuring devices being connected by means of a measuring line to the control device, and by means of the measurement of the volumetric flow the control device infers the current height of the platform.

7. The parking device according to one of the preceding claims, wherein the control device controls the pump drive on the basis of the determined height of the platform and/or on the basis of the measured angle of inclination.

8. The parking device according to one of the preceding claims, wherein in addition to the at least one tilt sensor at least one pressure sensor for the hydraulic oil and/or at least one temperature sensor and/or at least one volumetric flow measuring device for measuring the flow of hydraulic oil are provided and also the sensor signals of these additional sensors act on the selection of the current characteristic from the characteristic field.

9. The parking device according to one of the preceding claims, wherein at least two tilt sensors are arranged on different areas of the platform, and each determine the angle of inclination of the respective platform area about a longitudinal axis of the platform and supply it to the control device.

10. The parking device according to one of the preceding claims, wherein a central hydraulic pump driven by the pump drive is provided, and a branch to the hydraulic cylinders is provided in the hydraulic feed line after the hydraulic pump, in particular after the pressure reservoir, and a safety valve controlled by the control device is arranged between the hydraulic pump and the branch.

11. The parking device according to one of the preceding claims, wherein the control device controls the valves with a control frequency with pulse width modulation, and as a function of the angle of inclination it controls the pulse width and, as a result, the opening or closing times of the valves.

12. The parking device according to one of the preceding claims, wherein the control device has a monitoring module for the plausibility of the measure angle of inclination.

13. The parking device according to one of the preceding claims, wherein the control device has a calibration module for setting the zero position of the fitted tilt sensors.

14. A method for monitoring the angle of inclination of at least one platform, which is actively situated in an unmoved state, of a parking device, wherein the platform is arranged between two lifting means each driven by a drive, a tilt sensor is provided on the platform, and the tilt sensor is connected to a control device, and by means of control lines the control device acts on the drives or elements of the drives of the lifting means in such a way that when the angle of inclination is exceeded by means of an idle angle of inclination the angle of inclination is reduced again.

This data, for application number 2015214938, is current as of 2019-06-20 21:00 AEST