DE102013213201B4 - Cooling system with integrated hydrodynamic machine - Google Patents

Abstract

Cooling system comprising a cooler (23) for cooling a cooling medium, which is provided for cooling a machine, wherein a hydrodynamic retarder (21) is connected to the cooling system (15) and the cooling medium is simultaneously the working medium for the retarder (21) a cooling circuit (15) which can be connected to the toroidal working space (3) of the hydrodynamic machine (21) via an inlet channel (4, 4a) and an outlet channel (9), wherein a toroidal vortex area (8), vortex zone, of the working space (3) via at least one channel (4, 4a, 17, 18, 19) is connected to a container (6), characterized in that the edge region of the toroidal vortex region, vortex edge region (7), via a channel (17) with the Head region (6 a) of the container (6) is connected and the center of the toroidal vortex region, the vortex center, via a riser channel (18, 19) connected to the bottom portion of the container (6), wherein the container (6) unterh is arranged alb of the working space (3) of the retarder (21).

Description

The invention relates to a cooling system with a cooler for cooling a cooling medium, which is provided for cooling a machine, wherein a hydrodynamic machine is connected to the cooling system.

Such hydrodynamic machines. or retarder can z. B. water retarder in the drive train of a vehicle, in which the working fluid is at the same time the cooling water of the vehicle.

Such a cooling system comprises a circulation system or cooling circuit in which the cooling medium, in particular cooling water, can be circulated and cooled by means of a cooler. The hydrodynamic machine or retarder comprises a toroidal working space, which is formed by two paddle wheels, rotor and stator, and which is connected to the cooling circuit via an inlet channel and an outlet channel.

The working space of the retarder can be filled with cooling water via the inlet channel for a first operating state, braking. During braking, a circulatory flow forms in the working space about a center region, swirl region, wherein the cooling water hydrodynamically transmits a torque and / or a drive power from the first to the second blade wheel. For a second operating condition, non-braking operation, the cooling water is pumped out of the working space of the retarder to avoid torque and / or drive power transmission. To empty a residual amount of cooling water against the pressure present in the cooling system of the vehicle, the retarder comprises a pump. For example, pumps are known which are driven via the retarder shaft.

The emptying of the retarder is in principle first by means of the retardereigene dynamics by which the Meridiangeschwindigkeit the working medium is converted into a static pressure through which the working fluid is forced through the outlet hole in the stator from the working space in the outlet. Up to a certain degree of filling of the retarder, the static pressure which can be generated is greater than the pressure in the cooling system, so that the working medium can be forced into the cooling system via an outlet valve.

If the built-up static pressure is less than the pressure in the cooling system, the working fluid can not be pushed back into the cooling system, whereby a residual amount remains in the working space. This residual filling in the working space causes a torque or braking torque, which is substantially proportional to the static pressure in the outlet.

In order to reduce this retarder torque or this power loss, a pump is used to pump the remaining filling from the working space, but this also generates power loss.

Another possibility is in the DE 10 2009 055 975 A1 disclosed. Here a corresponding cooling system with a retarder is described. The cooling system is connected to a partially filled surge tank, which has an air space, wherein the air space is connected to the working space of the retarder via an air-conducting connection or optionally connectable to this.

In the DE 196 16 425 C1 discloses a switchable connection between the working space and a working fluid container.

Furthermore, in the DE 28 11 171 A1 discloses a retarder with a container disposed thereunder. Between the working space and the container several connections are provided to fill or empty the retarder. One of the objects of the invention is to propose an alternative solution as to how the degree of filling or the residual filling quantity in the working space of the retarder can be reduced.

The object is achieved by means of a hydrodynamic retarder with the features of claim 1. Further embodiments will become apparent from the dependent claims and the description.

According to the invention, the above-mentioned cooling system, with which a retarder is connected to modify such that a toroidal vortex region, vortex zone, the working space is connected via at least one channel with a container and the edge region of the toroidal vortex region, vortex edge region, via a channel connected to the head region of the container and the center of the toroidal vortex region, the vortex center, is connected via a riser channel to the bottom region of the container, wherein the container is arranged below the working space in the hydrodynamic machine.

The toroidal vortex region or the vortex zone is an area in the working space which is last filled during filling of the retarder and first emptied when emptying the retarder. During filling, an overpressure is created in the center area and a vacuum is created during emptying.

This will once be achieved that the working space of the retarder is filled only to a certain degree of filling, and that when emptying no working fluid from the container passes back into the working space or is sucked through the existing vacuum. If a certain degree of filling is achieved, excess working fluid is forced through the channel into the container. The channel may have a throttle or a valve.

The cross-section of the channel is very small in relation to the inlet or outlet channel, so that no influence on the braking performance occurs during braking operation.

As an "edge region" of the toroidal vortex region or of the core ring, any region on the blade which lies radially inside or radially outside the core ring center or is axially set back from the blade tip region can be considered.

Furthermore, it is achieved that when emptying the working space, thereby resulting in the center vacuum, the container is emptied. Thus, the compressed when filling in the container working fluid can be pumped out again.

Alternatively to the embodiment with a direct riser, the upper end of the riser channel may also terminate in the inlet channel and be connected to the center of the toroidal vortex region, the vortex center, via the inlet channel.

Through this course of the channel, a faster filling of the working space can take place when the center is connected to the bottom region of the container as well as the edge region of the toroidal vortex region with the upper region of the container. When filling the retarder causes the resulting overpressure in the vortex region via the channel also an overpressure in the container, whereby working fluid is forced through the riser into the inlet channel and from there into the working space.

In another embodiment, the retarder return line may be connected to the cooling system communicating with the outlet channel with the upper portion of the container via a connection channel. The connecting channel and the container are arranged and dimensioned such that a complete emptying of the working space in the container is possible. The complete or almost complete emptying of the working space minimizes the power loss is achieved.

Furthermore, a valve can be arranged between retarder return line and container, so that the connecting channel can be closed. By means of the valve, this can then be opened when, for one, the container has already been emptied by the vacuum in the swirl region, via the riser, and, secondly, the pressure is no longer sufficient to pump the residual working medium from the working space into the cooling circuit.

In a preferred embodiment, the container can be arranged below the working space in the hydrodynamic machine.

For the separation of the working space and the cooling circuit, a pressure-controlled valve can be arranged in the outlet channel. Preferably, the pressure-controlled valve is adjustable so that it opens only when the pressure in the outlet passage in front of the valve is higher than the operating pressure of the cooling water circulation system.

Further features of the device according to the invention and further advantages of the invention will become apparent from the following description of preferred embodiments with reference to the drawings.

The invention will be explained in more detail with reference to drawings.

In these show:

1 a cooling system with retarder and control

2 a paddle wheel of a retarder with the inlet and outlet channels

3 a first embodiment of the invention

4 a second embodiment of the invention

1 shows an inventive cooling system with retarder and control in the overview. The motor 16 as well as the retarder 21 are connected to a cooling system 15 connected. By means of the controller 14 consisting of several valves by means of an electro-pneumatic control 25 can be controlled or regulated, the braking power of the retarder can be controlled or regulated. The working medium of the retarder 21 is, as shown here, from the cooling water circuit 15 taken. One in the cooling circuit 15 existing radiator 23 is thus for the cooling of the engine 16 as well as for the dissipation of heat during braking operation from the retarder 21 responsible.

For pressure equalization is in the cooling circuit 15 a pressure equalization tank 24 available, the at least equalize the volume of the work space.

In 2 is a paddle wheel of a retarder with the inlet and outlet channels shown. This is the stator of the retarder. At least some of the blades 13 have openings. The openings are arranged in the region of the toroidal vortex region whose center line 22 is drawn here. Also plotted is the velocity distribution of the meridian velocities around the vortex center.

So are in one of the blades shown here 13 the riser 18 to the vortex center 8th and the channel 17 to the swirl edge area 7 to see. In some of the other illustrated blades, the inlet port is 4a arranged, which is also in the center area 8th ends.

In 3 a first embodiment of the retarder according to the invention is shown. In this embodiment, the container 6 arranged below the working area of the retarder. A channel 17 connects the edge area of the vertebral center, the vertebral edge area 7 , with the upper part of the container 6 , The cross section of this channel is very small in relation to the cross sections of the inlet channels. The diameter of the channel 17 is designed so that only relatively small working fluid volume in the container 6 can reach. Essentially, it is done via the channel 17 a pressure equalization between the container and the center area of the working space 3 ,

Another channel, a riser 18 connects the bottom of the container 6 , the ground area, with the center 8th of the spinal area. The center 8th lies exactly on the center line 22 of the toroidal vortex region or of the toroidal vortex region.

Through the riser 18 can during emptying of the retarder working fluid from the container 6 be sucked back into the work space. The sucking back takes place by the formation of a vacuum during the pumping of the working space.

The emptying of the container is supported 6 in that the vortex edge area 7 , sometimes in braking mode, is a zone that is not filled with liquid. In this zone there is a pressure slightly above the pressure in the inlet area (core ring center). This pressure drop can push gas (water-glycol-vapor mixture) into the container and thus the previously located therein liquid, via the riser 18 , in the inlet area of the retarder or the vortex center 8th transport. In principle, it is also sufficient if the proportion of gas in the inflowing stream is correspondingly greater than that in the stream flowing to the retarder. To eliminate unfavorable conditions valves (switchable) can be provided in the channels.

• – schließen des Einlasskanals Mittels einem Einlassventil, sodass die Kühlwasserzufuhr aus dem Kühlkreislauf in den Arbeitsraum 3 unterbrochen ist.
• – durch die Pumpwirkung der Retarderschaufeln wird der Arbeitsraum 3 entleert, bis der Pumpendruck nicht mehr ausreicht, die Arbeitsmediumrestmenge gegen den Kühlkreislaufdruck 15 durch das Auslassventil zu pumpen.
• – durch das Leerpumpen entsteht im Arbeitsraumzentrum 8 ein Vakuum, mittels dem der Behälter 6 über die Steigleitung 18 leergesaugt wird. Das aus dem Behälter 6 angesaugte Arbeitsmedium wird dadurch ebenfalls in den Kühlkreislauf zurückgepumpt.
• – Reicht der Druck nicht mehr aus, um die Arbeitsmediumrestmenge in den Kühlkreislauf zurückzupumpen, wird das Ventil 11 geöffnet (aktiv oder passiv), sodass die Arbeitsmediumrestmenge durch den Kanal 20 in den Behälter abfließen kann.
• – die Arbeitsmediumrestmenge wird nun im Kreislauf geführt, da das im Behälter 6 gesammelte Arbeitsmedium über die Steigleitung zurück in den Arbeitsraum gesaugt wird und anschließend wieder über den Verbindungskanal 20 in den Behälter 6 gepumpt wird. „Badewannenbetrieb” Die Querschnitte der Kanäle sind dafür so dimensioniert, dass die Verlustleitung möglichst klein ist und die Kühlung sichergestellt ist.

The following is a description of a shift cycle from the shift operation from the brake operation to the non-brake operation:

• - Close the inlet channel Using an inlet valve, so that the cooling water supply from the cooling circuit into the working space 3 is interrupted.
• - By the pumping action of the retarder blades is the working space 3 deflates until the pump pressure is no longer sufficient, the remaining working fluid against the cooling circuit pressure 15 to pump through the exhaust valve.
• - Empty pumping creates in the work center 8th a vacuum, by means of which the container 6 over the riser 18 is sucked out. That from the container 6 sucked working fluid is thereby pumped back into the cooling circuit.
• - If the pressure is no longer sufficient to pump back the residual working fluid into the cooling circuit, the valve becomes 11 open (active or passive) so that the working fluid remaining through the channel 20 can drain into the container.
• - The remaining working fluid is now recycled, as in the container 6 collected working fluid is sucked back via the riser back into the work space and then again via the connecting channel 20 in the container 6 is pumped. "Bathtub operation" The cross-sections of the ducts are dimensioned so that the leakage line is as small as possible and cooling is ensured.

• a) Bremsung innerhalb der Vollfüllparabel
• b) Bremsung außerhalb der Vollfüllparabel

When the retarder is switched on again, a distinction is made between two braking states:

• a) braking within the full filling parabola
• b) braking outside the full filling parabola

Steps to a)

• - Inlet valve opens and valve 11 closes. working space 3 is completely or at least substantially completely filled with working fluid.
• - Container 6 is filled because at a braking within the Vollfüllparabel the work space 3 is filled so that the center region at least to the vertebral edge region 7 filled with working fluid, so that working fluid through the channel 17 back into the container 6 can reach until it is completely filled with correspondingly long-lasting braking.

Steps to b)

• - Inlet valve opens and valve 11 closes. working space 3 is partially filled with working fluid.
• - Container 6 is emptied, as in a braking outside the Vollfüllparabel the work space 3 never completely filled so that the vortex area 7 . 8th is not filled with working fluid, so no working fluid through the channel 17 back into the container 6 can get.

The filling height of the container 6 is thus dependent on which speed and / or braking torque request is present during braking. A braking within the Vollfüllparabel causes a filling of the container 6 , a braking outside the Vollfüllparabel causes emptying of the container 6 ,

In summary, the braking operation in the area of the full filling parabola is characterized by: Coolant flow rate normal, in addition small bypass flow from the edge area of the core ring 7 through the channel 17 to the tank and back to the core ring center 8th through the riser 18 , container 6 is filled or remains full.

The braking operation outside the full filling parabolic diagram or during the switch-off process is characterized by: normal or decreasing coolant throughput, in addition small bypass flow from the edge area 7 of the core ring to the container 6 and back to the core ring center 8th , where the to the container 6 flowing stream has a higher gas content and thus emptied the container. Possibly. the switch-off process can go into a short braking process with a small residual torque before the retarder is completely switched off. Alternatively, the switch-off process can be selectively slowed down after falling below a certain residual torque (eg due to ABS requirement). The amount of residual torque can z. B. therefore stir that even in the worst case, the wheels must not block.

In 4 a second embodiment of the invention is shown. This design is different from the one in 3 shown embodiments in that the riser is made in two parts. The first part of the riser 19 connects the bottom area of the container 6 with the inlet channel 4 , The second part of the riser is divided by a section 4a of the intake channel 4 educated.

LIST OF REFERENCE NUMBERS

1

stator

2

rotor

3

working space

4

inlet channel

5

Retarderzulaufleitung

6

container

6a

upper tank area

6b

Bottom area of the container

7

Vortex edge region

8th

vortex center

9

exhaust port

10

Retarderrücklaufleitung

11

Valve

12

rotor shaft

13

shovel

14

hydraulic control

15

cooling system

16

engine

17

channel

18

rising channel

19

rising channel

20

connecting channel

21

retarder

22

Center line of the toroidal vortex area

23

cooler

24

Surge tank

25

electro-pneumatic control

Claims (6)

Cooling system with a radiator ( 23 ) for cooling a cooling medium, which is provided for cooling a machine, wherein a hydrodynamic retarder ( 21 ) with the cooling system ( 15 ) and the cooling medium at the same time the working medium for the retarder ( 21 ), with a cooling circuit ( 15 ), which is connected to the toroidal working space ( 3 ) of the hydrodynamic machine ( 21 ) via an inlet channel ( 4 . 4a ) and an outlet channel ( 9 ), wherein a toroidal vortex area ( 8th ), Vortex zone, the working space ( 3 ) via at least one channel ( 4 . 4a . 17 . 18 . 19 ) with a container ( 6 ), characterized in that the edge region of the toroidal vortex region, vortex edge region ( 7 ), via a channel ( 17 ) with the head area ( 6a ) of the container ( 6 ) and the center of the toroidal vortex region, the vortex center, via a riser channel ( 18 . 19 ) with the bottom portion of the container ( 6 ), the container ( 6 ) below the workspace ( 3 ) of the retarder ( 21 ) is arranged. Cooling system according to claim 1, characterized in that the upper end of the riser channel ( 19 ) in an inlet channel ( 4 ) and with the center of the toroidal vortex region, the vortex center, via an inlet channel ( 4a ) connected is. Cooling system according to claim 2, characterized in that to the outlet channel ( 9 ) a retarder return line ( 10 ), wherein the retarder return line ( 10 ) with the upper area of the container ( 6a ) via a connection channel ( 20 ). Cooling system according to claim 3, characterized in that between retarder return line ( 10 ) and containers ( 6 ) a valve ( 11 ) is arranged. Cooling system according to one of claims 3 and 4, characterized in that in the outlet channel ( 10 ) is arranged a pressure-controlled valve. Cooling system according to claim 5, characterized in that the pressure-controlled valve is adjustable so that it only opens when the pressure in the outlet channel ( 10 ) upstream of the valve is higher than the operating pressure of the cooling water circulation system.

Images