DE19706652A1 - Method for operating a hydrodynamic clutch and hydrodynamic clutch - Google Patents

Abstract

A process is disclosed for operating a hydrodynamic clutch with at least two blade wheels that form at least one torus-shaped working chamber (4) that can be filled with an operating medium. The filling degree is determined via a value that characterises the filling degree at least indirectly and when a maximum filling degree is attained, the operating medium supply is interrupted. The invention is characterised in that during the filling operation the operating medium is led in a substantially proportional manner to the filling degree from the working chamber (4) into an accumulation chamber (40) coupled to the working chamber. At least one dynamic pressure generator or sensor (32) is inserted into the accumulation chamber and arranged in such a way relative to the accumulation chamber that in a first filling state, in which the filling degree is lower than the maximum filling degree, no pressure or only a very small first pressure which is constant over the whole first filling state is generated in the dynamic pressure generating unit, whereas in a second filling state which corresponds to the maximum filling degree, a second, substantially higher pressure is generated and this second pressure is used at least indirectly for driving a device that influences the operating medium supply to the working chamber.

Description

The invention relates to a method for operating a hydrodynamic Coupling, in detail with the features from the upper range of the Claim 1 also a hydrodynamic clutch, in detail with the Features from the preamble of claim 8.

Hydrodynamic couplings for torque transmission are available in a variety of designs, for example as in the publications
1.) CR252
2.) JM Voith GmbH: "Hydrodynamics in drive technology"; United specialist publishers Krauskopf engineer Digest; Mainz 1987.
described, known. Couplings of this type comprise at least two blade wheels arranged coaxially to one another - a primary blade wheel and a secondary blade wheel, which together form at least one toroidal working space. The primary impeller acts as an impeller and the secondary impeller as a turbine wheel. The primary impeller can be connected in a rotationally fixed manner to a drive shaft which can be coupled at least indirectly to a drive machine. The secondary impeller can be connected in a rotationally fixed manner to an output shaft which can be coupled at least indirectly to a machine to be driven. The work rooms can be filled with equipment to transmit torque. The operating medium is circulated due to the primary blade wheel rotation during the operation of the clutch and generates a reaction moment on the blading of the secondary blade wheel. This cycle of equipment between the primary and secondary impeller is also known as the working cycle. However, not all of the flow energy is converted into reaction moment, only part of it, while the rest is converted into heat. The cooling of the equipment during the operation of the clutch can be implemented in different ways. A cooling circuit associated with the working circuit is conceivable, via which part of the operating medium is continuously guided during operation. For this purpose, for example, the heated operating medium can get into a pump shell rotating with the speed of the primary blade wheel via corresponding openings in the blade wheels and via nozzles. There, the equipment is received by a pitot tube that is counter to the direction of rotation. The pitot tube engages in the pump shell in the installed position above the coupling axis. Due to the pressure conditions, the flow energy of the operating medium, which is received via the pitot tube, is sufficient to feed it back to the coupling without additional aids via a cooling device, a cooler or a heat exchanger. For this purpose, a closed coolant circuit is assigned to the working circuit during operation.

In the steady state there is always a constant amount Resources in the clutch and in the cooling circuit. This cycle will no liquid added or removed. An increase or Reduction in the speed of the working machine is achieved by the Coupling equipment is supplied or removed. To this end are the work rooms also an inlet line or duct and a Drain or a drain line or channel for the purpose of filling and Associated with emptying. The inlet and outlet pipes are connected to an external one Equipment supply system, for example in the form of a Resource tanks, coupled. The assignment of the inlet and outlet lines to The workrooms can be used separately from the cooling circuit or of the lines or channels of the cooling circuit.

Other ways of replacing or cooling the in the work area located resources are conceivable, for example volumetric Cooling, d. H. the replacement of the equipment in the working cycle simultaneous removal of a certain amount of heated equipment  warmed operating mouth feeding of lower temperature equipment in the corresponding amount.

A major problem with hydrodynamic couplings is that depending on the application during commissioning or activation due to the Rotation of the rotor parts of the clutch in a housing there is a risk not to fill the clutch exactly, but to overfill it, as a certain one Degree of filling is very difficult to maintain exactly. In this case are then due to additional splashing losses between the runner parts themselves, d. H. the individual paddle wheels, and the housing and the rotor parts a deterioration in efficiency and an increasing Leakage at the individual labyrinths, d. H. the Equipment management lines. A solution which for To avoid these disadvantages, an additional drain line from the housing to the tank is not desirable. To avoid overfilling is therefore the supply line or the actuator for controlling the Inlet controlled by a fill signal. It acts as a fill signal for example the pressure in the drain line. This will have a Device for recording the current pressure value in the drain line measured in the work area. Via a pressure switch Exceeding a certain pressure, the system is electrically locked, so that a supply of additional equipment is prevented. The problem with Such a solution, however, is that this signal on the one hand is very imprecise due to the different boundary conditions and the further often not sufficient to overfill the clutch prevent. The pressure switch itself must always do this during commissioning can be set very precisely and is also able to withstand the pressure peaks Open fill valve in the supply line exposed. To illustrate this Problem: In detail, with the device for recording the pressure during a period from the empty state of the clutch to maximum filling of the clutch continuously a certain pressure value in  the drain line determined. This pressure value increases steadily. A clear one Rise change in a characteristic curve for the pressure depending on the Clutch filling only takes place in the area of an overfill, i.e. H. one Clutch filling <100%. Each pressure value is therefore proportional to one certain degree of filling. To determine a full filling, therefore corresponding pressure value can be recorded. Tolerances can be in the determination be incorporated. This leaves only a small pressure range, in which can be concluded that there is overcrowding. Within this limited pressure range is a control of the pressure switch necessary. However, since the pressure value determined in the line is still determined by a A number of other boundary factors can often be influenced pressure value recorded does not correspond to that theoretically assigned Degree of filling. An early termination of the filling at one The result is a filling level of <100% or overfilling.

The invention is therefore based on the object of a method for operating to develop a hydrodynamic clutch so that the Disadvantages of the prior art can be avoided. In detail there is one more effective, more suitable for different installation conditions and quick implement responsive protection against overfilling. The Solution according to the invention should be characterized by a low constructive and Distinguish tax and regulatory expenditure. The constructive Execution to realize the overfill protection should also be very be insensitive to interference and a maximum permissible degree of filling, which the generally maximum or a freely definable filling level can correspond as accurately and very quickly as possible and on it can react.

The solution according to the invention is characterized by the features of claim 1 featured. The design is characterized by the features of  Claim 4 characterized. Advantageous configurations are in each of the Subclaims described.

According to the invention, a hydrodynamic clutch is included at least two paddle wheels, a primary paddle wheel and one Secondary impeller, which together form at least one toroidal Form work space, operated such that only two Fill level states - a first fill level state that represents the state the non-filling and the partial filling, and a second Fill level condition that describes the maximum allowable fill level, can be distinguished, the first degree of filling being a certain one first, very low first pressure value is assigned and the second Degree of filling a second, increased compared to the first pressure value Pressure. For this purpose, the work space is coupled with a storage space. In one certain ratio to the filling level of the clutch Consumables from the work room into the storage space. In the storage space the Operating fluid level tapped via a dynamic pressure generating device. This is at least indirectly with a device for influencing the Inlet quantity to the work area, generally an actuating device Valve device coupled. The dynamic pressure generating device works so to speak on the black and white principle. In a first The degree of filling becomes essentially nonexistent, or only a very small one constant pressure generated and in a second fill level condition pressure significantly increased compared to the first degree of filling. First when the increased pressure occurs, the device becomes at least indirect influence on the feed quantity, generally an actuator controlled a valve device assigned to the inlet line and the Resource supply reduced or interrupted. According to the invention only the operating states non-filling or partial filling and full filling corresponding pressure signal assigned. It is important that the Transition from one state to the other a pronounced signal jump  is generated, which is reliably recognizable. This ensures that regardless of additional disturbances in the supply of equipment Overfilling is clearly recognizable. In particular, this system is not vulnerable against pressure surges caused by influencing the inflow volume serving filling valve. An exact setting of the pressure switch at Commissioning can be omitted. There is no need to optimize the system. The process is characterized by an easy to implement and accurate Determination of a maximum filling level being exceeded using a so-called black and white detection.

As a rule, the maximum permissible degree of filling is the actual, correspond to the maximum permissible degree of filling. This is generally 100%. However, it is also conceivable for the maximum permissible degree of filling to be defined in such a way that it is specific to a specific The intended use corresponds to the degree of filling that can be predetermined. This degree of filling can be maintained by any partial filling in relation to the maximum permissible degree of filling.

In terms of the device, a catch channel is assigned to the actual work space, which forms a storage space which is coupled to the work space at least indirectly for the purpose of supplying operating resources. The gutter is arranged on a diameter which, during operation of the hydrodynamic coupling, enables at least one filling of the storage space which is proportional to the degree of filling of the hydrodynamic coupling. In this, communicating with the work space, formed by the gutter, a dynamic pressure generating device, preferably in the form of a dynamic pressure tube for the purpose of scanning the level in the storage space is introduced. The dynamic pressure generating device is arranged opposite the storage space in such a way that it or, in the case of a dynamic pressure tube, the opening thereof when the coupling is not or only partially filled lies above or outside the operating fluid level in the storage space, so that it is not filled in this state of filling level. In this case, no operating material is discharged via the dynamic pressure pipe and therefore no pressure signal is generated. However, as soon as the degree of filling of the coupling reaches the maximum permissible degree of filling, that is to say the full filling as a rule, the storage space also fills up in such a way that the dynamic pressure generating device, in particular the dynamic pressure tube with its opening, projects into the operating fluid, absorbs operating fluid and thus a dynamic dynamic pressure of p _dynamic = (ρ / 2) xv ² generated.

It is essential to the invention that the dynamic pressure tube is arranged in the storage space in such a way that it only generates a high dynamic dynamic pressure when there is an operating medium level in the storage space which is proportional to the maximum degree of filling of the coupling. During the previous filling level conditions, which correspond to non-filling or partial filling, the opening of the dynamic pressure tube projects into a space in the storage space that is free of operating resources. In this state, no pressure or only a very low pressure is generated via the dynamic pressure generating device. This low pressure corresponds, for example, to the pressure which arises in an unfilled and open tube in the atmosphere. Since no pressure signal or only a very low pressure is generated in a region between the unfilled state of the hydrodynamic coupling and the maximum degree of filling, and a dynamic dynamic pressure of p _dynamic = (ρ / 2) xv ² is only generated in the state of the maximum degree of filling, the state of the maximum filling level of the hydrodynamic coupling is easily recognizable and without the influence of errors, because only the two filling level states are distinguished, which differ by a strong pressure change in the form of a pressure increase. This or the pressure signal which can be formed therefrom can then be used for the direct control of an actuating device of a device for at least indirectly influencing the flow rate in the inlet to the working space of the hydrodynamic coupling, specifically the actuator of a valve device.

The maximum degree of filling can actually be a maximum Filling degree, generally 100%, correspond. However, it is also conceivable, the maximum filling level as one for a concrete Use case to define the degree of filling to be observed. The maximum Degree of filling, which corresponds to the degree of filling that can be defined then by each degree of filling less than the actually maximum permissible Degree of filling definable.

The definition of the degree of filling to be maintained can be set by setting the Position of the dynamic pressure generating device, in particular the opening to The equipment is stored in the storage space. This can be done by Vertical direction d. H. in installation position by method in changed radially and in the circumferential direction in the storage space or pivoting will. The entire circumferential area can be regarded as the setting area for this will. The change in position can be used for a specific application permanently adjustable or additionally adjustable during operation. This has the advantage that different with an overfill protection Applications of a certain type of hydrodynamic coupling and Size through active adaptability to changing requirements can be covered.

An advantageous embodiment is to approach a separate gutter waive and to use the equipment gutter. This has the advantage that existing components can be used. At Arrangement of the dynamic pressure pipe in the equipment gutter or at Protrusion of the pitot tube end into the operating device gutter, the Pitot tube in a separate filling segment, which is the Resource gutter is arranged upstream, the knowledge is used that a  Draining from the equipment trough only takes place until the maximum Filling, d. H. the state of full filling has not yet been reached.

For the design of the storage space, which is essentially by the Gutter is determined, and the allocation of the gutter to Working cycle there are a variety of options. The gutter can be used as a separate component with the appropriate rotor parts Assignment to the work space can be releasably connected. Preferably, however, the gutter with a paddle wheel as a structural Unity, d. H. made in one piece.

The dynamic pressure generating device, which preferably as a dynamic pressure pipe has a part that carries an opening area. this part is preferably substantially parallel to that in the storage space adjusting resource level arranged. An arrangement inclined or perpendicular to it is also conceivable. The opening area extends at least partially perpendicular to the radial direction and in the circumferential direction, taking into account the direction of rotation. Preferably, the Opening area completely in the circumferential direction and is essentially arranged perpendicular to this.

The solution according to the invention is of any kind of hydrodynamic Couplings with variable filling can be used. The couplings can be used as Single-circuit clutches, which have a primary and a secondary impeller have, which together form a toroidal working space, or also as multi-circuit clutches, in which a plurality of primary and Secondary vane wheels form a large number of work spaces be. In the former case, the gutter can be the primary as well be assigned to the secondary paddle wheel or a shell. in the the latter case is only an assignment to one of the paddle wheels,  generally due to the external impellers constructive conditions possible.

The coupling between storage space and work space can be carried out in many ways be. Preferably, the connection between the interior of the Gutter and the work space via at least one in the paddle wheel incorporated through opening. The through opening allows one Transfer of equipment from the work area to the storage space. The The through opening can be designed differently. Through openings in the form of through holes or elongated holes, which each on a certain diameter of the paddle wheel are arranged are conceivable. Preferably a variety of Openings arranged on a diameter distributed in the circumferential direction. An arrangement on different diameters and / or one Combination of the individual types of through openings is also conceivable.

The through openings can be between the individual blades in the Blade base or in a radially inside the blade wheel lying area, which is free from the blading.

Depending on the design of the through opening, the filling can also be dependent from the speed difference, d. H. the slip between the primary and the Secondary wheel, so that a short bridging of the time Pressure signals may be required.

The part of the dynamic pressure tube carrying the opening is preferably in the arranged essentially parallel to the equipment level in the storage space. The Opening itself can be perpendicular or inclined to the equipment level be executed. Independence from the direction of rotation is ensured by the Providing at least two, with respect to the orientation of the one opening  supporting part of a pitot tube directed in opposite directions Pitot tubes, for example through a check valve can be coupled together. Another embodiment provides two pitot tubes, each with a separate pressure switch are coupled together. The pitot tubes dip through the the gutter and the outer dimensions of the paddle wheel, which the gutter is assigned, certain storage space that it is at a maximum filling level a dynamic pressure by immersing the Pitot tube generated in the equipment in the gutter. This The maximum degree of filling does not necessarily have to correspond to the full filling. A any degree of filling, which is defined as the maximum degree of filling also conceivable. This maximum degree of filling can accordingly The application of the hydrodynamic coupling can be defined. The Pitot tube can be made adjustable for this purpose, so that the Immersion height in the equipment in the gutter is variable. This offers the advantage of realizing a simple customization option Overfill protection to meet different requirements.

An embodiment of the component supporting the opening is in the radial direction also conceivable.

The gutter can, as already stated, as a separate gutter on Clutch rotor be executed, but there is also the Possibility of the equipment entry channel, d. H. the for the purpose of inflow to use the gutter coupled to the work area with the inlet pipe. in the the latter case are no further constructive measures the paddle wheels of the hydrodynamic clutch, but there is the possibility of existing facilities to fall back on.  

The pressure signal generated by the dynamic pressure tube, which for Control of the actuator of a device to influence the Filling levels, in particular a device for controlling the Supply volume used for the work area can be in a higher-level Control or regulating device are processed. Another possibility consists in the direct control of the actuator via the device for Detection of the degree of filling of the clutch at least indirectly characteristic size. The actuating device is effective in that that the filling is either interrupted or reduced. Since in As a rule, the pressure signal is not effective directly at the actuating device between the device for detecting the degree of filling a Conversion device for converting the pressure signal into a electrical control signal required. A pressure switch is preferably used for this purpose intended.

The solution according to the invention for realizing overfill protection by Detection of the degree of filling is of any kind of hydrodynamic couplings applicable. This is preferably done Use with hydrodynamic couplings, their work spaces too can be emptied during operation of the coupling.

To implement the function of filling level status detection and Use of the corresponding generated signal, in particular Pressure signals for controlling the device for influencing the Operating fluid supply to the working space of the hydrodynamic coupling is preferably a control device is provided. This includes at least one control device, each of which has at least one first Has input and a first output. The first entrance to the Control device is with the dynamic pressure generating device at least indirectly connectable. The first output of the control device is at least indirectly with the device for influencing the  Equipment supply to the working area of the hydrodynamic coupling connectable. At the first entrance, the one from the Dynamic pressure generating device generated dynamic pressure value or a value proportional to this, which differs in terms of dimension can differ from the dynamic pressure value, as a signal of Control device supplied. In the control device, for example either the determined dynamic pressure value or one, this proportional variable assigned a manipulated variable Y, which on the device to influence the supply of resources to the work area at least becomes indirectly effective. It is preferably only that Input signal at the control device, which increased the second Corresponds to the pressure value, assigned a manipulated variable. The control device acts as a simple conversion device, d. H. this arranges one Input signal either a control variable or not. The manipulated variable Y, which is output at the output of the control device can either directly on an actuator of the device Influencing the amount of equipment supplied to the work area of the hydrodynamic coupling or indirectly on this Actuator become effective. With the manipulated variable Y it can be an electrical, a hydraulic or a pneumatic or also act a mechanical quantity.

These functions performed by the control device can either through the appropriate selection of components and their coupling or can be realized via a corresponding microprocessor control.

To fulfill the basic function, i.e. H. the fill level condition detection and the control of the device for influencing the Resource supply quantity to the working space of the hydrodynamic coupling can, for example, at least two pressure switch devices be provided. One pressure switch device is one  Direction of rotation of the clutch and thus an opening area on the Back pressure generating device assigned. Take over the pressure switches the task of actuating the device to influence the Resource supply quantity to the working space of the hydrodynamic coupling to be controlled electrically. For this purpose, each pressure switching device comprises one Switch that implements the corresponding coupling. In the first Switch position of the switch of the pressure switch device, usually at When a fill signal is applied, the actuating device becomes the device to influence the amount of operating supplies to the work area controlled that equipment can get to the work area. The release the supply line to the work area can also be stepless. Due to the pressure signal from the dynamic pressure generating device the switch is moved to a second switching position. In this second Switching position is the device for influencing the Resource supply quantity to the working space of the hydrodynamic coupling brought into a switching position in which the equipment supply to Work space is reduced or interrupted.

This direct execution of the coupling between the individual Pressure switching devices and the actuator of the device for Influencing the amount of operating fluids to the work area of the hydrodynamic coupling provides the minimum equipment required Realization of the control task of the overfill protection. Additionally for this purpose, a lock can be provided in the circuit diagram, which a short circuit on the line affecting the device the supply volume connects to the work area, can switch off if necessary d. H. the actuating device is no longer acted upon electrically.

The switches of the pressure switching device are directly over the with the Back pressure generating device driven back pressure generated. This means that either the dynamic pressure at the switch is effective and  operated this, or a size proportional to the dynamic pressure. However, the former possibility is preferably implemented.

A preferred further embodiment of the configuration according to the device the control device contains at least one each Delay device in the form of a delay relay, which the individual pressure switching devices is connected downstream. This means that the Device for influencing the amount of resource supply to Working space of the hydrodynamic clutch, d. H. the filling valve, at Occurrence of a corresponding, the maximum degree of filling corresponding signals, delayed with a certain period of time is switched to overcrowding during a short-term operational To prevent pressure drop at the pressure switch. The period is chosen as low as possible. Periods of <0 to 5 seconds realized. This period can either be according to the Use case can be set or already by designing the Delay devices are fixed. In addition, for additional switching and safety functions including the normally open functions be used by pressure switches.

A version with a delay device is used with clutches regulated coolant circulation preferably not realized because the regulation could be adversely affected.

There is the possibility of connecting the pressure switch devices directly in series to switch to the filling valve, however, there is already a short pressure drop the device for influencing the pressure switching device Operating quantity in the working area of the hydrodynamic clutch actuated and thus replenished operating resources in the work area.  

The hydrodynamic clutch may be used to start a machine For example, only fill until one of the two Pressure switch devices a signal is present. Should the workspace however still not be completely filled, that means the signal from the Back pressure generating device falls again after a certain period of time a refill will be carried out automatically.

To realize a defined filling of the clutch, i. H. one predetermined degree of filling, the device for influencing the Flow to the work area, the so-called filling valve, as long as of the starting process is opened until the pressure switch device responds. Then the nominal operating point is waited for and possibly one Refill if the signal drops out of it Back pressure generating device made to the first pressure value. In addition, the drain valve, i.e. H. the device for influencing the Drainage rate from the work area, clocked open until the Pressure switching device the device for influencing the feed quantity no longer controlled. The filling valve is operated in cycles until the Level detection responds again, d. H. the Back pressure generating device generates the second pressure value. By constant monitoring of the filling level and by constant reaction to The degree of filling ensures that the desired one is defined Fill level is set. The defined degree of filling depends on the position of the dynamic pressure generating device, in particular the Opening area in the storage space. The position of the Back pressure generating device in the storage space or its opening area in relation to the storage space places a fixed maximum permissible fill level. This is generally the maximum permissible filling level of 100%, but can also be a certain Describe partial fill level. It is also conceivable that the  maximum permissible degree of filling by the Back pressure generating device is arranged adjustable in the storage space.

Coupling versions in which the work area Coolant circuit during continuous operation for the purpose of cooling is assigned, d. H. part of the equipment is used during operation emitted from the work space and this again via a circuit fed, and this circuit separately a feed and a Drain line can be activated for the purpose of volumetric cooling, for example, via appropriate valve devices, is after Response of the temperature monitoring for the exchange of equipment first the drain valve in the outlet from the work space hydrodynamic clutch opened and after an adjustable period of time, which can also be zero, also switched on the filling valve. In this In this case, resources are taken from the working cycle and at the same time new cooled equipment is supplied. Speaks during this Resource exchange the signal for the fill level status detection on, d. H. a second increased pressure value at the Created dynamic pressure generating device, the device for Influencing the supply volume to the work area, d. H. the filling valve for the set time closed to prevent overfilling. Is the The temperature drops below a permissible limit, the clutch again, as defined when starting, filled. H. the facility for Influencing the amount of resources supplied to the work area is like this switched that the resource supply coupled to the work space is, after the occurrence of a signal for the second pressure value at the Condition detection device the filling valve is closed again.

To implement the individual control tasks, the Start-up time, the power consumption as a function of the time Operating medium temperature lead to fault or warning messages that  as further input variables for controlling the actuation devices of the individual valves must also be taken into account. Furthermore, also the clutch fill time lead to a message when a certain predefined value is exceeded.

The valve devices for influencing the cross section to be released mechanically, in the inlet or outlet line of the work area operated by electric motor, electromagnetic, hydro or pneumostatic will. To control the actuators is between Back pressure generating device and actuating device at least one To provide signal conversion device.

The achievement of the object according to the invention is based on Figures explained. It also shows the following:

Figs. 1a and 1b show an embodiment of the invention a hydrodynamic coupling with overflow protection at the example of a coupling with two working cycles, and a diagram for explaining the operation of the overflow cutout;

. Clarify Figures 2a and 2b way of an embodiment of the prior art and a graph showing the problem of the use of a circulating detected pressure value for controlling the filling valve;

FIGS. 3a and 3b illustrate embodiments of the invention a gutter-pitot tube assembly;

FIG. 4a to 4b illustrate specific embodiments according to the invention shaped gutter back pressure tube assemblies;

FIG. 5a and 5b illustrate an embodiment of the connection cables to the back pressure pipe;

Fig. 6a and 6b illustrate embodiments for sensing pressure values in the area of resource gutter;

Fig. 7a to 7d illustrate by means of simplified control scheme, the device practical embodiment for implementing the control functions;

. Clarify Figures 8a and 8b based on Signalflußbildern the operation during the start and during the cooling of the example of the volumetric cooling in continuous operation;

FIG. 9 illustrates the mode of operation described in FIG. 8a on the basis of diagrams.

To illustrate the problem of the embodiments of the prior art are according to the Fig. 2a and 2b, the functional diagram of a generic hydrodynamic coupling, here p the example of a coupling with two working cycles and the associated closed resources cooling circuit, and a characteristic curve showing the dependence of the instantaneous pressure shown in the drain lines of the degree of filling of the coupling.

Fig. 2a shows a simplified representation of a functional diagram of a device known from the prior art generic hydrodynamic clutch 1, which is designed as a double cycle clutch closed resources circulation in a closed cooling circuit. For this purpose, this clutch 1 comprises two paddle wheels, a primary paddle wheel 2 and its secondary paddle wheel 3 , which together form at least two toroidal working spaces 4 and 5 . The primary impeller 2 can be coupled via a drive shaft 6 at least indirectly to a drive machine (not shown here in detail). The secondary impeller can be connected in a rotationally fixed manner to an output shaft 7 for coupling to the output side.

The two toroidal work spaces 4 and 5 can be filled with an operating medium. Oil or water can be used as equipment. The operating medium is circulated in the operation of the hydrodynamic clutch as a torque transmission device in the toroidal working spaces 4 and 5 and thus forms a closed working circuit 9.1 and 9.2 between the two impellers, the primary impeller 2 and the secondary impeller 3 .

A coolant circuit 10 is assigned to the working circuit in order to dissipate the heat accumulating in the working circuits 9.1 and 9.2 . The operating medium is dispensed through openings (not shown here) in the area of the outer diameter D _{AS of} the primary impeller wheels during the operation of the hydrodynamic clutch 1 into a pump shell 11 which is coupled to the primary impeller wheel 2 in a rotationally fixed manner. The pump shell 11 is arranged in the radial direction with respect to the coupling axis A in the area of the outer circumference U _{AS of} the two paddle wheels 2 and 3 . In the pump shell 11, the operating means is received by at least one property against the direction of rotation pitot tube 12th For this purpose, this protrudes into the pump shell 11 above the coupling axis A in the installed position of the hydrodynamic clutch 1 . This dynamic pressure tube 12 is part of the coolant circuit 10 and opens into a line 13 , which functions as an outlet line from the pump bowl 11 and at the same time as an inlet line to a cooling device 14 , which can be designed as a cooler or as a heat exchanger. The cooling device 14 is connected via a line 15 to an operating means feed channel 16 to the work rooms 4 and 5 . In the case shown, the coolant circuit 10 is a closed circuit. The line course of this circuit 10 can also be used for filling and emptying the toroidal work spaces 4 and 5 . For this purpose, the work rooms 4 and 5 are assigned at least indirectly via the coolant circuit 10 a supply line 17 and a discharge line 18 , which are coupled to an operating fluid tank 19 . These individual lines, here the supply line 17 and the discharge line 18 , can be connected via corresponding devices in the form of valve devices. The drain line 18 is connected by means of a switching valve functioning as an emptying valve, for example in the form of a 2/2-way valve 20 . The supply line 17 is connected via a switching valve acting as a filling valve in the form of a 3/2-way valve 21 .

In the steady state there is always a constant amount of operating fluid in the coupling 1 , ie in the two toroidal working spaces 4 and 5 and in the coolant circuit 10 . No liquid is then supplied or removed from this coolant circuit 10 . An increase or decrease in the speed of the working machine is achieved in that the coupling can be supplied or removed from the coupling by means of filling or emptying valves, here via the connection of the individual supply and discharge lines 17 and 18 . Filling takes place via the feed line 17 from an operating medium tank 19 , into the inlet line 15 , which is coupled to the toroidal working spaces 4 and 5 via an operating medium introduction channel 16 . The filling quantity is influenced via the 3/2-way valve 21 , which in a first switching position I ₂₁ decouples the supply line 15 to the equipment inlet channel 16 from the supply line 17 and in a second switching position II ₂₁ connects the supply line 17 to the supply line 15 .

To avoid exceeding a maximum permissible degree of filling of the hydrodynamic coupling 1 , in particular the working spaces 4 or 5 , the drain line, in particular the line 13 in the coolant circuit 10 , in which part of the operating medium from the working circuit 9.1 or 9.2 is led back into the working circuit via a cooler, assigned a device for detecting the pressure p. This device is designated 23 here. During the operation of the hydrodynamic clutch 1 , as the speed of the drive machine increases, an increasing pressure p builds up by dispensing the operating medium into the pump shell 11 . This pressure p, which is then present in the coolant circuit 10 , in particular in the line 13 , is used to implement overload protection. In the implementation from the prior art, the knowledge is used that the pressure p in the line 13 is also increased when the permissible maximum degree of filling is exceeded. This pressure is tapped and used as an actuating signal to control an actuating device 25 on the 3/2-way valve 21 . The supply of operating fluid from the operating fluid tank 19 via the feed line 17 to the operating fluid inlet channel 16 on the hydrodynamic coupling 1 is thus controlled via the pressure. The control itself is usually electromagnetic, ie the pressure signal must be converted into a corresponding electrical control signal via a conversion device. The function of the conversion is carried out by a pressure switch, not shown in detail here. However, this must be set exactly during commissioning and is also exposed to the pressure peaks due to the opened 3/2-way valve 21 .

In FIG. 2b, to a diagram in which the pressure applied p as a function of the clutch filling or the filling degree in% is shown. From this it can be seen that only from a clutch filling, which corresponds to the maximum filling level, which is generally 100%, is there a change in the pressure values in the lines such that the pressure value curve has an increased increase. In the range of a coupling fill level of 0% to 100%, the pressure p generated in the line system increases substantially continuously. This steady increase is still present in the range of the maximum permissible clutch filling level of 100%. Only from this degree of filling, ie in the event of an overfilling, does the pressure p change in such a way that a steeper increase or a stronger increase is recorded. In order to be able to react actively even when the filling is full, the connection between the device for detecting the pressure p and the actuator for influencing the feed quantity to the hydrodynamic coupling is limited to a small range with regard to its reaction. The actuating device is actuated only when a pressure p occurs with a size that lies in the specified range. However, this pressure value must be determined as precisely as possible by the detection device. Additional disturbance variables that can influence the pressure value in the system can already falsify the result to be determined. With such a system, it is therefore difficult to exactly determine the point in time when the coupling is full, ie the maximum permissible degree of filling, and at the same time to avoid overfilling by rapid reaction, in particular by actuating the actuator to influence the supply quantity to the work spaces. This control therefore works very imprecisely and is very prone to errors.

In Fig. 1 is a solution of the invention for realizing the overflow cutout by means of a hydrodynamic coupling, as shown in Fig. 2 will be described, is shown. The basic structure of the hydrodynamic coupling 1 corresponds, essentially as described in FIG. 2a. The same reference numerals are therefore used for the same elements.

Here, too, the hydrodynamic coupling 1 comprises a cooling circuit 10 assigned to the working circuit, and inlet and outlet lines 17 and 18 assigned to the working spaces 4 and 5 . According to the work space or work spaces 4 and 5 is assigned a so-called gutter 26 , which preferably runs in the circumferential direction of the hydrodynamic coupling 1 and is arranged in a radial direction with respect to the coupling axis A in an area which is radial in relation to the dimensions Direction extends at most over the maximum diameter of the working space 4 or 5 . This gutter 26 is connected to the work space 4 and 5 in a communicating manner. The connection takes place, for example, in the form of a through opening 27 , which can be designed in various ways and in the radial direction in a region between an outer diameter of the channel d _ra , which corresponds to the radially outer boundary of the collecting channel 26 , and that, the collecting channel in the radial direction the smallest diameter-limiting areas, for example the surfaces 29 and 30 is incorporated into the primary impeller 2 . The through openings 27 can be arranged either in the blade-free, radially inner region of the primary blade wheel 2 or, preferably, in the blade base of the bladed part 31 of the primary blade wheel 2 . The arrangement of the gutter 26 and the passage opening 27 with respect to the impeller is dependent on the desired filling depending on the degree of filling of the clutch 1 . The through openings 27 can be designed as through bores, which are designed in a circular or in the form of elongated holes, which preferably extend over at least a part of the circumference of the impeller on a certain diameter.

The filling level in the storage space 40 described by the gutter 26 , which is determined by the degree of filling in the hydrodynamic coupling 1 , in particular the working spaces 4 and 5 and the design of the through openings 27 , is tapped by means of a dynamic pressure pipe 32 . The dynamic pressure pipe 32 is designed and arranged in such a way that filling with liquid takes place only from a fill level 34 in the gutter 26 , which corresponds to a maximum permissible degree of filling in the work spaces 4 and 5 . By filling the _dynamic pressure tube 32 , a so-called _dynamic pressure p is _dynamically generated, which corresponds to a second pressure value p ₂ , which is higher than a first pressure value p ₁ without filling the _dynamic pressure tube 32 with operating medium, as a manipulated variable for acting on the 3/2-way valve 21 Influencing the amount of equipment supplied to the working cycle 9.1 or 9.2 is used. The maximum permissible degree of filling preferably corresponds to a maximum degree of filling of 100%.

In the case of partial filling, that is to say a degree of filling less than the maximum permissible degree of filling, there is also an exchange of operating media between the gutter 26 and the working spaces 4 and 5 , however, no _dynamic pressure p is generated _dynamically or only a negligibly low pressure p ₁ in the _dynamic pressure pipe 32 . In this case, no signal is given to act on the actuating device of the 3/2-way valve 21 . This signal is only generated when the maximum permissible filling quantity is reached.

The maximum permissible filling quantity can be determined by the upper filling limit, a filling level of 100%, or freely selectable between a filling level of 0% and 100%. According to the degree of filling, the opening of the dynamic pressure tube 32 must always be arranged in the storage space 40 which can be filled with operating medium and reaches an operating medium level 34 .

In FIG. 1b, the dependence of the determined dynamic pressure values on the clutch charge is plotted in a diagram for the embodiment according to the invention. From this it can be seen that with partial filling, ie an operating state of the hydrodynamic coupling 1 , in which the fluid level 34 in the storage space 40 of the gutter 26 below the dynamic pressure tube 32 , a pressure value p is determined in the dynamic pressure tube 32 which essentially corresponds to the air pressure. Only when the dynamic pressure pipe 32 is immersed in the operating equipment located in the storage space 40 and the dynamic dynamic pressure of P _dyn = (ρ / 2) xv ^{2 is} generated, the immersion of the dynamic pressure pipe 32 in the operating equipment located in the collecting channel 26 only at a certain degree of filling , for example 100%, a second pressure value p or a strong pressure value change Δp in the dynamic pressure tube is suddenly determined, which is used as a recognition feature for reaching the maximum permissible degree of filling in the working space 4 or 5 . What is important here is the pronounced signal jump shown in the diagram, which should have a size that can also be recognized under the influence of disturbance variables.

FIGS. 3a and 3b illustrate in a section of a paddle wheel, preferably the primary blade 2, in each case a further possibility for the design of the connection between the working space, where the working space 4 and the collecting channel 26 and through the gutter 26 and the outer contour 37 of the primary paddle wheel there is determined storage space 40 .

FIG. 3a shows a detail of a primary blade 2, to which a collecting channel 26 is associated. The gutter 26 is formed by a disc-shaped element 50 which can be detachably connected to the primary impeller 2 . The outer contour 37 of the primary impeller and the gutter form a storage space 40 . In this storage space 40 there extends a device for detecting a quantity, which at least indirectly characterizes the degree of filling, in the form of a dynamic pressure tube 32 .

The gutter 26 extends in the radial direction into an area which is in the area of the working space 4 or at its height. The connection between the storage space 40 and the working space 4 takes place via an obliquely designed through opening 27.1 , which extends from the paddle wheel base 36 to the outside of the paddle wheel 37 , which at the same time forms an outer boundary surface for the gutter 26 .

In the embodiment shown, the storage space 40 is arranged in the radial direction in a region which corresponds to the radial arrangement of the blading 44 .

In FIG. 3b, embodiments are shown of a gutter 26 and a storage space 40, which are arranged in the radial direction in the radially inner area of the primary blade wheel 2. The gutter 26 is arranged in an area of the blading 44 of the primary blade wheel 2 which is located in the radial direction. In the installed position, the pressure tube 32 is arranged depending on the degree of filling to be limited, in the case shown above the coupling axis A.

In FIGS. 4a and 4b further concrete embodiments are shown. Fig. 4a1 illustrates a portion of the primary blade wheel 2, which is assigned a collecting channel 26 which is arranged in a region which lies between the inner _IS D and the outer diameter D _AS of the blading 44th The gutter 26 extends in the radial direction into an area which is in the area of the working space 4 or at its height. The connection between the storage space 40 and the working space 4 takes place via an obliquely designed through opening 27.1 , which extends from the paddle wheel base 36 to the outside of the paddle wheel 37 , which at the same time forms an outer boundary surface for the gutter 26 . The gutter 26 is formed only by means of an annular component 38 . The dynamic pressure tube 32.2 extends through the annular component 38 and projects into the storage space 40 formed by the gutter 26 . The dynamic pressure pipe 32.2 is designed such that the opening area 41.2 is arranged in the installed position in the radial direction above the passage through the annular element 38 . The part 42.2 carrying the opening area preferably extends essentially parallel to an operating medium level 43 which is set in the storage space 40 .

FIGS. 4a2 shows a view II according to FIG. 4a1. The course of the part 42.2 carrying the opening area 41.2 can be seen from this. Furthermore, it can be seen that due to the orientation in the opening area 41.2 in the circumferential direction in the case of changing operating modes, ie reversing operation, a second dynamic pressure pipe 32.1 is required, the opening area 41.1 of which extends in the opposite direction to the opening area 41.2 with respect to the circumferential direction. The two dynamic pressure pipes 32.1 and 32.2 are connected to a common line 49 via a check valve 46 via the line sections 47 and 48 respectively assigned to them.

In FIG. 4b1 an embodiment of a drip channel is illustrated, which is disposed in the radially inner area of the primary blade wheel 2. The gutter 26 is arranged in an area of the blading 44 of the primary blade wheel 2 which is located in the radial direction. Here, too, the storage space is limited by the inner diameter d _{R of} the gutter 26 , the outer contour 37 of the primary impeller 2 , and the surfaces 29 of the components connected in a rotationally fixed manner to the primary impeller 2 .

The coupling of the storage space 40 with the working space 4 takes place via through openings 27.1 (not shown here), as shown in FIG. 4a1. However, there is also the possibility, under certain conditions, of coupling the work space and storage space through through-openings which are arranged in the radial region of the primary paddle wheel 2 , which is free of blading 44 .

The operating medium level 43 is here at the level of the opening area 41.2. of the pitot tube 32.2 . The dynamic pressure tube 32.2 is also designed here in such a way that the opening area 41.2 is aligned in the circumferential direction and is immersed in the operating medium located in the storage space 40 .

In the installed position, the dynamic pressure tube 32 is arranged according to the desired degree of filling to be limited at a certain distance from the coupling axis A. In the illustrated case, the dynamic pressure tube 32.2 is arranged above the coupling axis A.

Here too, a second dynamic pressure generating device in the form of a second dynamic pressure tube 32.1 is required when the direction of rotation of the component of the dynamic pressure tube 32.2 carrying the opening area is changed. This is shown in a view II-II in Fig. 4b2. From this it can be seen that both opening areas 41.2 and 41.1 are directed opposite to each other in the circumferential direction. Here, too, both dynamic pressure pipes 32.1 and 32.2 are coupled to a common line 49 via a line 47 and 48 , which are connected to one another via a check valve 46 .

In the two cases ( FIGS. 4a and 4b), the gutter 26 is formed with the aid of a ring-shaped component 38 , which is connected to the primary impeller 2 in a rotationally fixed manner. In theory, however, there is also the possibility of creating the gutter together with the primary paddle wheel as an assembly.

Furthermore, the suction pressure tube in the designs shown in both figures is mounted in component 55 on the housing.

FIGS. 5a and 5b illustrate a further possible embodiment of the pitot tube 32. The component 55 carrying the dynamic pressure pipes 32.1 and 32.2 is fastened to the housing. Compared to the options shown in FIGS. 4a and 4b, the line is routed from the dynamic pressure pipe 32 via a pipe connection 56 fastened to the housing wall. Fig. 5b a illustrates a view III-III according to Fig. 5a.

The basic structure of the paddle wheel 2 , work space 4 and the associated storage space 40 , as well as the extension of the dynamic pressure tube into the gutter 26 corresponds to that described in FIGS . 4a1.2 and 4b1.2, which is why it will not be discussed in detail here. The same reference numerals have therefore been used for the same elements.

Figs. 3 to 5 illustrate only presentations under the gutter and the passage openings. Other possibilities with which the same function can be performed are also conceivable. Depending on the design of the coupling with one or more working spaces, the gutter can be assigned to either the primary impeller or the secondary impeller or a shell in the former case, but in the latter case only to the primary impeller for design reasons. The gutter itself is designed as a separate component or as a component with the corresponding paddle wheel.

An advantageous embodiment, which is not shown in detail in FIG. 6 here, is that the operating material collecting channel 22 is used in the working cycle 9.1 or 9.2 as the collecting channel or for recording the pressure value. This also preferably runs over a certain diameter over the entire circumference. The dynamic pressure pipe 32 can in this case be arranged in the operating material gutter 22 , ie in a region below the coupling axis A in the radially inner region of the impeller, here the primary impeller 2 . Here, the knowledge is utilized, that a draining from the gutter 22 takes place only as long is filled to the clutch, from this point will not flow out of the operating means gutter 22 more instead. For this purpose, the dynamic pressure pipe can also be arranged in the filling segment 57 , which is assigned to the operating material collecting channel 22 . Such a possible arrangement is shown in FIG. 6b. This only shows the filling segment 57 and shows the course of the dynamic pressure pipe 32 in a schematically simplified manner.

FIGS. 7a to 7d illustrate a simplified representation based on control scheme, the use of the dynamic impact pressure value generated by the dynamic pressure generating means p _dynamically for controlling an adjusting device for influencing the operating medium supply to the working space 4 and 5 of the hydrodynamic coupling 1.

Fig. 7a1 and 7a2, the general possibility of use illustrated using a block diagram of the dynamic impact pressure value p _dynamically = ρ / 2v ² provided by means of the dynamic pressure generating means. For this purpose, a control device 60 has at least one control device 61 , which in each case comprises at least one first input 62 and one first output 63 . The first input 62 can be coupled at least indirectly to the dynamic pressure generating device, while the first output 63 is coupled at least indirectly to the device for influencing the feed quantity to the work space. This device is designed here as a valve device, preferably in the form of a 3/2-way valve and is designated by the reference number 64 .

A pressure signal is fed to the control device 61 via the first input 62 . This pressure signal is formed either by the first pressure value p ₁ or by the second increased pressure value p ₂ . In accordance with the signal present at input 62, manipulated variable Y for controlling the device for influencing the feed quantity to the working space of the hydrodynamic coupling is formed at output 63 . If the first pressure value p _{1 is present} at the input 62, the manipulated variable formed is zero, ie no signal is generated to control the device for influencing the feed quantity to the working space of the hydrodynamic clutch 64 . When a second increased pressure value is applied, which preferably corresponds directly to the hydrodynamic _dynamic pressure p generated with the _dynamic pressure generating device 32 , a manipulated variable Y is output at the output 63 , which causes the device 64 to take a position for influencing the feed quantity to the working space of the hydrodynamic clutch, that the inflow to the work area, and thus the flow of resources to the work area, is interrupted. Since these devices for influencing the inflow quantity are generally valve devices, the manipulated variable Y is output in a form which is effective on the actuating devices 65 of the device for influencing the inflow quantity to the working space of the hydrodynamic coupling. The actuation devices 65 can be acted upon electrically, pneumatically, hydraulically or mechanically. The manipulated variable Y is therefore to be formed in accordance with the selection of the actuating device 65 . The device for influencing the feed quantity to the working space of the hydrodynamic coupling 64 is preferably actuated electromagnetically.

In the simplest case, the valve device 64 is designed with a reset device, for example in the form of a spring device, which sets the switching position II ₂₁ on the valve device 64 due to its restoring force when the force applied to the actuating device 65 is reduced. When the valve device 64 is actuated electromagnetically to set the switching position I ₂₁ , a manipulated variable Y is then output, which interrupts the power supply.

However, the entire control of the valve device 64 is preferably carried out by the control device 60 . For this purpose, the control device 61, as shown in Fig. 7a2, a further second input 75 associated for providing a signal to fill the working chamber of the hydrodynamic coupling. The second input 75 can be coupled to a device for specifying a signal for filling the hydrodynamic coupling. If a signal is present at the second input, which is directed at least indirectly to a desired filling of the clutch, a manipulated variable Y is output at the output, which is used to actuate the valve device 64 , in particular to apply an actuating force to the actuating device in such a way that the valve device Line at least partially releases the filling of the work area. An additional application of a signal for the first pressure value p ₁ at the first input 62 then has no influence on the manipulated variable Y. However, if the second increased pressure value p ₂ is present at the first input 62 , this has priority over the filling signal. In this case, the manipulated variable Y is formed in such a way that the valve device assumes a switch position which reduces or interrupts the supply of operating fluid to the work area.

The control device 61 can be designed as a separate control device. An implementation as a simple conversion device, which serves to convert input signals into output signals of different dimensions, is also conceivable. The individual control functions can be implemented, for example, by means of a microprocessor control or by means of switching elements to be coupled accordingly.

Fig. 7b illustrates the basis of a control scheme for a pressure switch connection required for achieving the object of the invention minimal equipment of the control device 60.1. This includes two pressure switch devices, a first pressure switch device 66 and a second pressure switch device 67 , which are used for different directions of rotation of the rotor parts of the hydrodynamic clutch 1 . The first pressure switch device 66 is provided, for example, for the left-hand direction of rotation, while the second pressure switch device 67 can only be activated in the right-hand direction of rotation. The pressure switch devices are coupled to a voltage source and form the connecting links to the actuating device 65 of the device 64 for influencing the feed quantity to the working space of the hydrodynamic coupling, here in the form of a 2/2-way valve. Both pressure switch devices 66 and 67 are arranged in series. Their respective switching elements 68 and 69 each enable a connection between a voltage source (not shown in detail here) and the actuating device 65 of the device for influencing the feed quantity to the working space of the hydrodynamic coupling 64 in the first switching position 1/2 or 1/2. In a second switch position 1/4 or 1/4 this connection is interrupted. The switching devices 68 and 69 are thereby in dependence on the dynamic pressure generated by the dynamic pressure generating means 32 p _effort of the second elevated pressure value p ₂ corresponds actuated. For this purpose, the dynamic pressure p can be used _dynamically directly or only indirectly to act on the switching elements 68 and 69 .

The device for influencing the feed quantity to the working space of the hydrodynamic clutch, the 2/2-way valve 64 , likewise has at least two switching positions, a first switching position 80 and a second switching position 81 . In the first switching position 80 , a resource supply device (not shown in detail here) is coupled to the working space - or the feed line 82 - to the working space of the hydrodynamic coupling. In the second switch position 81 , the flow of resources between the resources supply device and the feed line 82 is interrupted. Since the solution according to the invention is based on a so-called black-and-white principle, that is to say essentially only two different pressure values or pressure value states are determined for the two filling degree states, these two pressure value states can be actuated by the switching elements 68 or 69 of the pressure switching devices 66 or 67 are transmitted. Only when a dynamic dynamic pressure value p _dynamic is _detected is the corresponding pressure switching device actuated in such a way that the switching elements 68 or 69 are brought into the respective switching positions 1/2 or 1/2 or 1/4 or 1/4, which form a connection between one The voltage source and the actuating device 65 of the device for influencing the feed quantity to the working space of the hydrodynamic clutch 64 enable or interrupt such that it assumes either the first switching position 80 or the second switching position 81 .

FIG. 7c illustrates an embodiment of a control device 60.2 corresponding to FIG. 7b, but with an additional securing option . The basic structure corresponds essentially to that described in FIG. 7b. Here too, the individual switches 68 and 69 of the individual pressure switching devices 66 and 67 are acted upon by the dynamic pressure generated by the dynamic pressure generating device 32 or by a pressure value proportional to this. Depending on the action of the switching elements and depending on the direction of rotation of the rotor parts of the hydrodynamic coupling, the device 64 for influencing the feed quantity to the working space of the hydrodynamic coupling 64 , or its actuating device 65, is also acted on here. Furthermore, a third switch 85 is provided, which serves to interrupt the electrical connection between the actuating device 65 and the individual pressure switch devices 66 and 67 . This additional switch 85 is controlled via a locking device 86 . The control is preferably electrical, but can also be done mechanically, hydraulically or pneumatically. This additional locking by means of the locking element 86 makes it possible to avoid a short circuit on the device for influencing the amount of operating fluid supply to the work area.

FIG. 7d shows a further development of the minimal design illustrated in FIG. 7b for realizing the function according to the invention. The control device is designated 60.3 here. As already described in FIGS. 7b and 7c, this also comprises two pressure switch devices 66 and 67, respectively. These two pressure switch devices are also each assigned to a direction of rotation of the rotor parts of the hydrodynamic clutch 1 . The first pressure switch device 66 is designed for a rotation direction on the left and the second pressure switch device 67 for a rotation direction on the right. Depending on the design of the dynamic pressure generating device 32, these two pressure switch devices 66 and 67 are each coupled either to a separate dynamic pressure pipe oriented for the corresponding direction of rotation, or generally to the dynamic pressure generating device. The coupling is essentially limited to the fact that the actuating signal for actuating the switching elements 68 and 69 of the two pressure switching devices 66 and 67 acts directly on the switches 68 and 69 . For this purpose, the pressure signal can _dynamically correspond to the dynamic dynamic pressure p generated or be proportional to it. However, an embodiment is also conceivable in which a variable which is at least proportional to the dynamic pressure and which can have a different dimension acts on the switches 68 and 69 . The loading can always be done directly or indirectly via other intermediate sizes.

Each of the two pressure switch devices 66 and 67 enables, via the switch elements 68 and 69, an adjustment or disconnection of the actuation device 65 of the device for influencing the supply of operating fluid to the working space of the hydrodynamic coupling 64 with a voltage source, not shown in detail here. The connection is achieved in the switching position 1/2 or 1/2 of the two pressure switch devices. In the other switching position 1/4 or 1/4, there is a decoupling between the voltage supply device and the actuating device 65 .

To avoid overfilling in the event of a brief drop in the signal from the level detection device, ie generally the dynamic pressure generating device, a delay device in the form of a delay relay 90 or 91 is connected downstream of each of the two pressure switches 66 and 67 . In the illustrated case, the pressure switching device 66, the delay relay 91 and the pressure switching device 67, the delay relay 90 are assigned and connected downstream. The individual delay relays 90 and 91 are designed such that they prevent the clutch from overfilling if the signal for the second pressure value p ₂ drops out briefly. This time period can be freely selected or can be predefined according to the design of the delay relays 90 and 91 . A so-called delay period of 0 to 5 seconds is preferably selected. Specifically , for the control device 60.3 shown in FIG. 7d, this means that, for example, when a maximum degree of filling is recognized by generating a dynamic dynamic pressure in the dynamic pressure generating device , for example when rotating in the direction of rotation to the left, the first pressure switching device 66 with the dynamic dynamic pressure p _{dynamic determined} or one to this proportional size, is driven. The switching element 68 is brought into the switching position 1/4. The pressure switching device 66 switches off the delay relay 91 .

The embodiments described in FIGS. 7b to 7d, in particular the individual control tasks, can also be implemented by means of a microprocessor control. In this case, it is also conceivable that other conversion units for converting the variable characterizing the dynamic dynamic pressure into a variable corresponding to the dimension for controlling the actuating device 65 are converted. The specific design and the assignment of different structural components for realizing the functions mentioned is at the discretion of the individual specialist.

Figs. 8a illustrated with reference to a signal flow the possible procedure for setting a defined filling or a predeterminable filling level by adjusting the position of the dynamic pressure pump of the hydrodynamic coupling, especially during startup. The individual designations in the flow chart are explained in the following legend for FIGS . 8a and 8b.

Legend of logic plans

Fill = 1: fill valve open; Infeed from Operating medium
Drain = 1: drain valve closed; no removal of medium
ÜFS _r

= 1: Level detection addressed, direction of rotation to the right
ÜFS _l

= 1: Level detection addressed, direction of rotation to the left
ÜFS = 1: Level detection addressed (left or right)
n ₂

≧ 0.9 n _N

: Output speed at which level detection is safe
n ₂

≦ n _n

: is working
Fill command = 1: Command from the system to fill the VTK
Fill = 0: fill valve closed, no feed
Drain = 0: drain valve open, VTK is drained
t ₁

= 0-5 s: cycle time for emptying (emptying = 0)
t ₂

= 0-5 s: waiting time (emptying = 1)
t ₃

= 0-5 s: cycle time for filling (filling = 1)
t ₄

= 0-5 s: waiting time (filling = 0)
t ₅

= 0-5 s: Waiting time for water exchange (filling = 1)
T ≧ 50 ° C (higher?): Fault overtemperature
T _allow

≦ 30 ° C (higher?): Permissible temperature after water exchange.

The decisive factor is whether there is a filling command, ie a signal to control the device 64 for influencing the feed quantity to the working space of the hydrodynamic coupling. If this signal is given, the device for influencing the feed quantity is controlled in such a way that it connects, for example, an operating medium supply unit in the form of a tank to the work space or the feed line to the work space of the hydrodynamic coupling 1 . The drain from the working area of the hydrodynamic coupling is closed. During the filling process it is now checked whether there is a signal for a second increased pressure value p ₂ from the filling level condition detection device, ie the filling level detection UFS in the storage space is addressed. The signals of both devices are preferably monitored for different directions of rotation of the rotor parts of the hydrodynamic coupling. If only the first pressure value p _{1 is} determined, ie the fill level detection has not responded, the opening area of the dynamic pressure generating device is in the resource-free space, the filling process is continued. If there is a signal for the second increased pressure value p ₂ , ie if the level detection ÜFS responds, the device for influencing the feed quantity to the working space of the hydrodynamic coupling is activated and the supply of operating fluid to the working space is interrupted immediately, usually by closing the filling valve. After the interruption, the level is monitored further. If the level detection device does not give a signal, ie if only the first pressure value p _{1 is} determined, the filling is continued. When the second pressure value p ₂ is detected, that is to say when the degree of filling is identified, which corresponds to the maximum permissible degree of filling, a further check is carried out to determine whether the speed n _{2 of} the individual rotor parts, in particular the primary blade wheel functioning as a pump impeller, has already exceeded a certain predeterminable speed, which preferably corresponds to the speed from which the degree of filling state detection is most likely to work error-free. If this speed falls below n ₂ and the further presence of a signal formed by the filling level condition detection device for an achieved maximum permissible filling level is continued until this speed n _{2 is} reached and then emptying of operating resources from the working space of the hydrodynamic coupling. In the other case, the filling process is continued. However, the emptying process does not take place completely, but rather during a cycle time t ₁ of preferably 0 to 5 seconds. For this purpose, a device for influencing the outlet from the hydrodynamic coupling is activated. This device can be a valve in the outlet or in the drain line from the working space of the hydrodynamic coupling. However, it is also conceivable to assign the drain line to the work area via an intermediate coolant circuit.

After the emptying process after a certain waiting time t ₂ , it is again checked whether the maximum filling level of the h 10362 00070 552 001000280000000200012000285911025100040 0002019706652 00004 10243 hydrodynamic coupling has been reached. If there is still a signal from the fill level detection, which indicates that the maximum fill level has been reached, further measures are taken in order to be able to empty the work space. However, if a degree of filling is determined which is below the defined maximum permissible degree of filling, refilling is carried out again. This preferably also takes place in a time period t ₃ of 0 to 5 seconds. After a certain further second waiting time t ₄ , it is then checked again whether the level detection has responded, ie whether a second increased pressure p _{2 is} determined. Depending on the result, it is either refilled or the filling is kept constant.

By means of the process steps for Setting a defined degree of filling of a hydrodynamic Coupling becomes apparent that in some cases a mere control is not sufficient but constant monitoring in connection with the Control option for setting a predefined fill level of the hydrodynamic clutch is required. Refill and emptying operations are carried out until the signal for the maximum permissible filling level, which can also be specified, is output becomes.  

Referring to the embodiments in FIGS. 7b to 7d is to achieve a pre-definable filling of the hydrodynamic coupling the device for influencing the amount of feed to the working chamber of the hydrodynamic coupling, ie, the fill valve open as long until the relevant for the current direction of rotation pressure switching means being responsive . Then the nominal operating point must be waited for and, if necessary, refilled. In addition, the drain valve can be opened cyclically until the pressure switch device drops out again. Another possibility is to cycle the filling valve until the level detection responds again.

FIG. 8b illustrated with reference to a signal flow, the procedure for setting a according to the position of the dynamic pressure pump freely selectable degree of filling in a predefined coupling design with volumetric resource exchange. For this purpose, a functional diagram of a hydrodynamic coupling is shown in FIG. 8b1 to illustrate the procedure for volumetric cooling. This is designated 1 here. The hydrodynamic clutch 1 has a primary impeller 2 and a secondary impeller 3 . The primary impeller functions as a pump impeller, the secondary impeller as a turbine wheel: the primary impeller and the secondary impeller form at least one toroidal working space 4 with one another. During operation, the operating medium flows around between the bladed parts of the primary and secondary impeller in the work space 4 . This revolution is also known as the so-called work cycle. Since part of the flow energy is converted into heat due to the circulation, it is necessary to remove the equipment from the working cycle and to cool it during continuous operation. For this purpose, a circuit 91 is assigned to the work area, which is used for the circulation of equipment during continuous operation. An inlet line 92 and an outlet line 93 are each assigned to this circuit 91 . The inlet line 92 and the outlet line 93 can be connected to the circuit either separately or together. A switching valve is provided for this purpose. A first switching valve 94 , which enables a coupling between the discharge line 93 and the circuit 91 , and a further switching device 95 , which serves to couple or decouple the inlet line 92 to the circuit 91 . The first switching device 94 is designed in the form of a 3/2-way valve, the second switching device 95 is designed at least as a 2/2-way valve. The equipment circulating in the circuit 91 during continuous operation is an item of equipment emerging from the work space via openings on the paddle wheels into the interior of the clutch housing or else an item of equipment emerging with the paddle wheels with rotating rotors.

A device for detecting the temperature in the circuit 91 is provided in the discharge line 96 from the working space 4 of the hydrodynamic coupling. In accordance with the determined temperature value, which should not exceed a predeterminable target value, a decision is made as to whether equipment from the circuit 91 should be exchanged for equipment with a lower temperature. When the permissible temperature in the discharge line 96 is exceeded, the first switching device 94 , ie the 3/2-way valve, is acted on in such a way that it assumes a first switching position I, in which the outlet line 96 is coupled to the discharge line 93 . In this way, the operating medium, which would otherwise flow around in the circuit 91 for cooling purposes, is at least partially guided out of the circuit 91 and thus also out of the working circuit. This equipment must be replaced with new equipment. For this purpose, the 2/2-way valve 95 is brought into a first switching position 95.1 , in which the feed line 92 is coupled to the circuit 91 . Corresponding to the operating fluid withdrawn from the circuit 91 or the working circuit in the working space 4 , it is necessary to feed new operating means into the circuit 91 . This feed takes place via the 2-way valve 95 .

The first switching device 94 has a further second switching positions II. In the second switching position II, the operating medium which has emerged from the working space in the circuit 91 and which then functions as a closed circuit is returned to the working space 4 .

For the defined filling of the coupling, reference can be made to the procedure described in the signal flow diagram in accordance with FIG. 8a. When an elevated temperature T is determined, ie after the temperature monitoring device has responded, the drain valve is then opened in accordance with the signal flow diagram 8 b1 and, after a certain adjustable time t ₅ , the valve in the inlet to the working space of the hydrodynamic coupling. The temperature T is monitored further. If this is lower than a permissible temperature T _perm. , The degree of filling can be set in accordance with the procedure as described in FIG. 8a. The interface is 1. If the range of the permissible temperature T _{perm is} not reached and a response of the fill level detection device is detected at the same time, the fill valve is closed and the emptying process is continued.

In FIG. 9, the operating modes of the device for influencing the amount of operating fluid in the working space of the hydrodynamic coupling, the drain valve, the drive speeds and the level detection over time are entered on the basis of diagrams for the starting process. These relationships correspond to those described in FIG. 8a on the basis of the signal flow diagram. It can be seen from this diagram that the device for influencing the feed quantity to the working space of the hydrodynamic coupling, ie the filling valve, is open until the level detection indicates the second increased pressure value. Since the level detection is a so-called black and white circuit, it can be assumed that only the two states 0 and 1 are taken into account. Furthermore, it can be seen that when the second pressure value at the dynamic pressure generating device is reached, the filling valve is closed. While the fill level detection indicates a state during further operation that only corresponds to a partial fill, the fill valve is influenced in such a way that a refill takes place in the work area. After the refilling process has ended, ie when the filling valve is already closed again, the maximum level of filling is still displayed by the level detection. From this diagram it can also be seen that the outlet from the working space of the hydrodynamic coupling, in particular the drain valve, is also included in the strategy for the defined filling level setting. Thus, during a period in which the fill level detection continuously indicates a fill level that corresponds to the maximum permissible fill level, the drain valves in the outlet from the working space of the hydrodynamic coupling are temporarily opened in a targeted manner.

The selection of those required to perform the individual functions Valve devices are made according to the application. Preferably however, multi-way valves are used. These can also be stepless be operable.

Realizing the possibility of a stepless or gradual Adjustment of the dynamic pressure pump position can be carried out in many different ways will. The specific constructive interpretation is at the discretion of Specialist and takes place according to the circumstances of the application. The same applies to the implementation of additional functions, for example delayed response to a corresponding pressure signal  from the dynamic pressure detection device, priority of Level signal before a signal for a desired filling quantity.

Claims (38)

1. A method for operating a hydrodynamic clutch, comprising at least two paddle wheels which form at least one toroidal work space which can be filled with an operating medium; in which the degree of filling is determined via a quantity that characterizes the degree of filling at least indirectly, and when the maximum degree of filling is reached, the supply of operating medium is interrupted;
characterized by the following features:

• 1.1 in which, during the filling process, resources are conveyed from the work space into a storage space coupled to the work space, essentially proportional to the degree of filling;
• 1.2 in which at least one dynamic pressure generating device is introduced into the storage space;
• 1.3 in which the dynamic pressure generating device is arranged opposite the storage space in such a way that
• 1.3.1 in a first filling level condition, which corresponds to a filling level less than the maximum filling level, no or only a very small first pressure, which is constant over the entire first filling level condition, is generated in the dynamic pressure generating unit and
• 1.3.2 in a second filling level condition, which corresponds to a maximum filling level, a second, substantially higher pressure is generated and this second pressure is used at least indirectly to control a device for influencing the supply of operating fluid to the work space.

2. A method of operating a hydrodynamic clutch according to claim 1 with a dynamic pressure generating device in the form of at least one dynamic pressure tube with an opening area extending into the storage space;

• 2.1 in which only in the second filling level condition, operating material in the storage space is received through the opening area on the dynamic pressure tube and a dynamic pressure is generated in the dynamic pressure tube, which acts as a second increased pressure value;
• 2.2 at which the second increased pressure acts at least indirectly as an input signal of a control device.

3. The method according to any one of claims 1 or 2, characterized characterized in that the maximum degree of filling theoretically corresponds to the maximum permissible filling level of 100%. 4. The method according to any one of claims 1 or 2, characterized characterized in that the maximum degree of filling by setting the Position of the dynamic pressure generating device in relation to the Storage space is freely adjustable. 5. The method according to any one of claims 1 to 4, characterized in that the interruption of the supply of resources to the work space delayed for the acquisition of the second increased pressure value he follows. 6. The method according to any one of claims 1 to 5, characterized by the following features:

• 6.1 in which, after an interruption when a first pressure value is detected, the supply of operating fluid is released again;
• 6.2 in which, when the second increased pressure value is detected again, the current drive speed or a variable that at least indirectly characterizes it is determined and compared with a predeterminable comparison variable, from which an error-free mode of operation of the level detection occurs;
• 6.3 in which the filling process is continued when the drive speed falls below or the size at least indirectly characterizing it and only the display of the first pressure value, while upon detection of the second state of filling level the filling process is continued until the comparison variable is reached;
• 6.4 when the comparison variable is reached and the second filling level condition is recognized, the working space of the hydrodynamic coupling is temporarily emptied, the filling process being reactivated when the first pressure value is present and carried out over a predefinable period of time;
• 6.5 after a waiting period, the presence of a first or second print is checked again.

7. The method according to any one of claims 1 to 6, wherein at least one cooling circuit is assigned to the work space, characterized by the following features:

• 7.1 at which the current temperature is determined in the cooling circuit;
• 7.2 at which equipment is emptied from the cooling circuit over a certain period of time when a maximum permissible temperature is exceeded;
• 7.3 at which equipment is fed into the cooling circuit during or after this period;
• 7.4 at which the temperature in the coolant circuit is determined after the equipment has been exchanged and compared with a further second permissible temperature value for the operating state after the equipment has been exchanged, and in the event of a deviation and additional occurrence of the second increased pressure value, the filling process is terminated and equipment is emptied again.

8. Hydrodynamic clutch

• 8.1 with at least two paddle wheels, a primary paddle wheel and a secondary paddle wheel, which together form at least one toroidal working space that can be filled with operating medium;
• 8.2 the toroidal work space is assigned at least one supply line for operating resources;
• 8.3 the device is assigned a device for recording a quantity that at least indirectly characterizes the degree of filling;
• 8.4 the device is at least indirectly coupled to a device for influencing the amount of operating material in the supply line; characterized by the following features:
• 8.5 includes the device for detecting a quantity that at least indirectly characterizes the degree of filling
• 8.5.1 a storage space assigned to a paddle wheel and coupled to the work space and
• 8.5.2 a dynamic pressure generating device which extends into the storage space, the dynamic pressure generating device being assigned to the storage space in such a way that the dynamic pressure generating device only absorbs operating resources and the dynamic dynamic pressure generated as a result when the operating fluid level in the storage space corresponds to a specific maximum degree of filling Signal for at least indirect control of the device for influencing the amount of resources in the supply line to reduce the amount of resources to be supplied or decoupling the supply line from the work space is used.

9. Hydrodynamic coupling according to claim 8, characterized characterized in that the storage space of one, a paddle wheel associated gutter is formed.   10. Hydrodynamic coupling according to claim 9, characterized characterized in that the gutter by at least one separate, Detachably connectable component is formed with the paddle wheel. 11. Hydrodynamic coupling according to claim 9, characterized characterized in that the gutter is formed by the paddle wheel. 12. Hydrodynamic coupling according to one of claims 8 to 11, characterized in that the dynamic pressure generating device in their position relative to the storage space is adjustable. 13. Hydrodynamic coupling according to one of claims 8 to 12, characterized in that the dynamic pressure generating device in Shape of at least one dynamic pressure pipe is executed. 14. Hydrodynamic coupling according to claim 13, characterized by the following features:

• 14.1 the dynamic pressure tube comprises at least one component, which carries an opening area, for receiving operating materials;
• 14.2 the component carrying the opening area is connected to a pipe part which is at least partially directed against the direction of gravity in the radial direction with respect to the coupling axis.

15. Hydrodynamic coupling according to claim 14, characterized characterized in that the component supporting the opening area in essentially parallel to one that is set in the storage space Equipment level is executed. 16. Hydrodynamic coupling according to one of claims 14 or 15, characterized in that the bearing the opening area Component extends in the direction of the paddle wheel.   17. Hydrodynamic coupling according to one of claims 14 or 15, characterized in that the bearing the opening area Component extends in the circumferential direction. 18. Hydrodynamic coupling according to one of claims 16 or 17, characterized by the following features:

• 18.1 the opening area is directed in the circumferential direction;
• 18.2 for the reversing mode, two dynamic pressure pipes with oppositely directed opening areas are provided;
• 18.3 the two dynamic pressure pipes can be connected to a common line via a valve device.

19. Hydrodynamic coupling according to one of claims 16 or 17, characterized by the following features:

• 19.1 the opening area is directed in the circumferential direction;
• 19.2 for reversing operation, two oppositely directed opening areas are provided on the dynamic pressure tube.

20. Hydrodynamic coupling according to one of claims 14 to 16, characterized in that the bearing the opening area Component of, based on the coupling axis in the radial direction at least partly directed against the direction of gravity Pipe part is formed. 21. Hydrodynamic coupling according to one of claims 8 to 20, characterized in that the coupling between the work space and Storage space via at least one through opening in the paddle wheel he follows.   22. Hydrodynamic coupling according to claim 21, characterized characterized in that the through openings in the radial direction in Area of the bladed part of the paddle wheel are arranged. 23. Hydrodynamic coupling according to claim 21 or 22, characterized characterized in that the through openings in the radial direction in Area of the part of the paddle wheel free from blading is arranged. 24. Hydrodynamic coupling according to one of claims 8 to 23, characterized in that the primary and Form secondary working wheel with each other. 25. Hydrodynamic coupling according to claim 24, characterized characterized in that the primary and secondary impeller form at least one other work space together. 26. Hydrodynamic coupling according to one of claims 24 or 25, characterized in that the storage space the primary impeller assigned. 27. Hydrodynamic coupling according to claim 24, characterized characterized in that the storage space the secondary paddle wheel assigned. 28. Hydrodynamic coupling according to one of claims 8 to 27, characterized in that the storage space extends in the radial direction up to extends an area that has a smaller diameter than that Paddle wheel outer circumference is arranged.   29. Hydrodynamic coupling according to one of claims 8 to 28, characterized in that the dynamic pressure generating device a facility for converting the in the Back pressure generating device generated pressure in an electrical Control signal to control an actuator of the device Influencing the amount of resource supply is assigned. 30. Hydrodynamic coupling according to claim 29, characterized characterized in that the means for converting the in the Back pressure generating device generated pressure in an electrical Control signal to control an actuator of the device Influencing the amount of equipment supply as a pressure switch is executed. 31. Hydrodynamic coupling according to claim 30, characterized characterized in that the pressure control devices delay relay assigned. 32. Hydrodynamic coupling according to one of claims 29 to 31, characterized in that the device for influencing the Resource supply quantity is a valve device. 33. Hydrodynamic coupling according to one of claims 8 to 32, characterized by the following features:

• 33.1 there is a control device with at least a first input and a second input;
• 33.2 the first input is at least indirectly coupled to the dynamic pressure generating device;
• 33.3 the first output is coupled to the device for influencing the amount of operating fluid.

34. Hydrodynamic coupling according to claim 33, characterized by the following features:

• 34.1 a further second input is provided;
• 34.2 the second input is coupled to a device for specifying a fill signal;
• 34.3 there is provided a manipulated variable formation device which, in accordance with the input signals, forms a manipulated variable for at least indirectly actuating the device for influencing the amount of operating fluid supplied.

35. Hydrodynamic coupling according to one of claims 8 to 34,

• 35.1 the operating fluid supply system is assigned to the hydrodynamic coupling;
• 35.2 The equipment supply system comprises at least one closed circuit, which is used for equipment circulation during operation;
  characterized by the following features:
• 35.3 at least one inlet line and one outlet line can be connected separately or together to the closed circuit;
• 35.4 there is at least one device for at least indirectly determining the temperature of the operating medium, which can be coupled to an actuating device for a switching valve for connecting the closed circuit to the drain line;
• 35.5 a device for determining the pressure in the circuit is provided, which is coupled to an actuating device of a valve for connecting the inlet line.

36. Hydrodynamic coupling according to claim 35, characterized by the following features:

• 36.1 the switching valve is arranged in a closed circuit and comprises at least two switching positions (I, II);
• 36.2 in a first switching position (I) of the switching valve, the circuit is coupled to the drain line;
• 36.3 in a second switching position (II) of the switching valve, the equipment circulates in a closed circuit;
• 36.4 the valve for connecting the inlet line has at least two switching positions, the circuit being connected to the inlet line in a first switching position of the valve and decoupled in a second switching position.

37. Hydrodynamic coupling according to one of claims 34 to 36, characterized in that the switching valve as a 3/2-way valve is executed. 38. Hydrodynamic coupling according to one of claims 34 to 37, characterized in that the valve is designed as a 2-way valve is.