阅读说明：本技术 用于封闭缓速器的工作腔放气通道的设备 (Device for closing a working chamber bleed air passage of a retarder ) 是由 莫里茨·马伊 迪特尔·劳克曼 马丁·德格 扬尼克·贝克 于 2020-03-30 设计创作，主要内容包括：本发明涉及一种用于封闭缓速器的工作腔放气通道的设备。对于用于封闭放气通道(15)的设备,放气通道用于将缓速器(1)中的由转子(3)和定子(4)形成的能被填充工作介质的工作腔(9)与周围环境连接起来,该设备包括止回阀(16),所述止回阀具备浮子体(17)并且具备带有密封平面(19)的浮子腔(18),其中,浮子体(17)被设计成：使得当工作介质和/或工作介质泡沫经由放气通道(15)被运送到浮子腔(18)中时,浮子体向着密封平面(19)地从打开位置运动到关闭位置中。本发明提出的是,沿流动方向(A)看,在工作腔(9)与密封平面(19)之间设置有借助其能改变工作介质泡沫的密度的机构。(The invention relates to a device for closing a bleed air passage of a working chamber of a retarder. For an apparatus for closing an air bleed channel (15) for connecting a working chamber (9) which is formed by a rotor (3) and a stator (4) and can be filled with a working medium in a retarder (1) with the surroundings, the apparatus comprises a non-return valve (16) which is provided with a float body (17) and with a float cavity (18) with a sealing plane (19), wherein the float body (17) is designed such that: so that when the working medium and/or the working medium foam is conveyed into the float chamber (18) via the degassing channel (15), the float body is moved from the open position into the closed position towards the sealing plane (19). According to the invention, means are provided between the working chamber (9) and the sealing plane (19) as seen in the flow direction (A), by means of which the density of the working medium foam can be varied.)

1. Device for closing an air bleed channel (15) for connecting a working chamber (9) which is formed by a rotor (3) and a stator (4) and can be filled with a working medium in a retarder (1) to the surroundings, comprising a non-return valve (16) which is provided with a float body (17) and with a float cavity (18) with a sealing plane (19), wherein the float body (17) is designed such that: such that when the working medium and/or the working medium foam is conveyed into the float chamber (18) via the gas discharge channel (15), the float body is moved from an open position into a closed position towards the sealing plane (19),

it is characterized in that the preparation method is characterized in that,

between the working chamber (9) and the sealing plane (19), viewed in the flow direction (A), means (20) are provided by means of which the density of the working medium foam can be varied.

2. The apparatus as set forth in claim 1, wherein,

it is characterized in that the preparation method is characterized in that,

the float body (17) is designed such that: the float body (17) is moved into the closed position when the working medium foam in the float chamber (18) and the density of the working medium foam reach a definable level.

3. The apparatus as set forth in claim 1, wherein,

it is characterized in that the preparation method is characterized in that,

the means (20) is arranged in the deflation channel before and/or inside the float cavity.

4. The apparatus as set forth in claim 3, wherein,

it is characterized in that the preparation method is characterized in that,

the means (20) is a wire mesh or a screen element.

5. The apparatus as set forth in claim 4, wherein,

it is characterized in that the preparation method is characterized in that,

the wire mesh is made of a wire braid having a wire thickness of 0.01 to 1mm and a mesh width of 4 to 10 mm.

6. The apparatus as set forth in claim 5, wherein,

it is characterized in that the preparation method is characterized in that,

the wire mesh is produced by deformation of a multi-layered wire braid, wherein the individual wires of the wire braid are deformed to form a filter structure.

7. The apparatus as set forth in claim 4, wherein,

it is characterized in that the preparation method is characterized in that,

the wire mesh has a passable area of between 0.5% and 40%.

8. The apparatus as set forth in claim 5, wherein,

it is characterized in that the preparation method is characterized in that,

the wire mesh is constructed of a stainless steel braid.

9. The apparatus as set forth in claim 2, wherein,

it is characterized in that the preparation method is characterized in that,

the mechanism comprises a movable part by means of which the foam structure of the working medium can be broken up or changed.

10. The apparatus as set forth in claim 2, wherein,

it is characterized in that the preparation method is characterized in that,

the mechanism comprises a nozzle by means of which a working medium can be injected into the bleed air channel (15).

11. The apparatus as set forth in claim 1, wherein,

it is characterized in that the preparation method is characterized in that,

an oil separator (21) is provided between the check valve (16) and the surroundings.

12. The apparatus of any one of claims 1 to 10,

it is characterized in that the preparation method is characterized in that,

the non-return valve (16) and/or the means (20) are produced by a so-called additive manufacturing method.

Technical Field

The invention relates to an arrangement for closing a bleed air channel in a retarder, wherein the bleed air channel connects a working chamber with the surroundings.

Background

Such a working chamber is for example a working chamber formed between the rotor and the stator of the retarder. However, it is also conceivable that it is any chamber that can be filled with oil, for example the oil tank of the retarder.

When switching the retarder to the braking mode, compressed air is led into the oil tank, whereby oil is pressed from the oil tank into the working chamber of the retarder. The contained air can escape from the working chamber via a passage whose one opening terminates in the center of the working chamber. Although a major proportion of the oil is forced into the circulating flow of the annular configuration in the cross section of the working chamber by the rotation of the rotor, this results in the formation of oil bubbles in the center of the working chamber, which oil bubbles are conveyed out of the working chamber via the bleed air channel. The oil foam has a lower density than the liquid oil, so that the function of the device for closing the gas discharge channel (in particular the check valve with the float body) is no longer functional and results in the oil foam escaping from the gas discharge channel into the surroundings.

When switching to the non-braking mode, oil is carried or pumped back out of the working chamber to the oil tank. This also results in foam formation which is extruded from the pressure tank.

In particular, the occurrence of large foam formations can lead to a malfunction of the check valve, since the float of the check valve cannot acquire sufficient buoyancy, so that oil foam can escape into the surroundings.

Oil foam will occur when the retarder oil is contaminated, for example, by water, wrong/bad oil or undesired air transport (non-tightness).

DE 102013006611 a1 discloses a ventilation device with a non-return valve, which is connected to the center of the working chamber via a channel. An additional volume is proposed here, which is preceded by a non-return valve. By increasing the volume, the flow rate is reduced, which leads to an improved separation of the air fraction and the working medium fraction. Additionally, an insert may be provided in the channel, which insert protrudes into the channel and provides an increased surface, thereby improving the separation.

DE 102013207004 a1 discloses a ventilation device for a fuel tank. To separate the oil from the air, a labyrinth is preceded by a valve.

Another solution is proposed in DE 102012002039 a 1. The air from the oil tank is guided through the centrifugal separator.

Disclosure of Invention

The object of the invention is to provide a device for closing an air discharge duct, which has an improved function, so that no oil enters the surroundings.

According to the invention, this object is achieved by a device according to claim 1. Further advantageous embodiments and preferred solutions are described in the dependent claims.

According to the invention, a device for closing the bleed air channel is proposed, which is arranged to connect a working chamber, which can be filled with a working medium and which is formed by the rotor and the stator, in the retarder to the surroundings. The device comprises a non-return valve which is provided with a float body and with a float chamber with a sealing plane, wherein the float body is designed such that it moves from an open position into a closed position towards the sealing plane when the working medium and/or the working medium foam is conveyed into the float chamber via the degassing channel.

In order to improve the functionality, it is proposed according to the invention that, viewed in the flow direction, a means is provided between the working chamber and the sealing plane, by means of which the density of the working medium foam can be varied.

The change of the foam of the working medium is achieved in that the air content of the foam is reduced before the foam reaches the sealing plane, i.e. the foam structure is changed and/or destroyed. The air that has become free can then escape via the still open non-return valve. Furthermore, once the working medium and/or the treated foam (having a higher density) have accumulated in the float cavity and reached a definable level, at this point the float body will move or float into a closed position such that the check valve is safely closed.

The check valve according to the invention, in particular the float body, is therefore designed such that: the float body is moved into the closed position when the working medium foam in the float chamber and the density of the working medium foam reach a definable level.

The mechanism may be disposed in the deflation channel before and/or within the float cavity in various embodiments. Wherein, in the sense of the invention, the float chamber forms a partial section of the deflation channel.

These means may be for example wire mesh or screen elements. The wire mesh may be made of a wire braid having a mesh width of 4mm to 10 mm. In this case, a mesh width of, in particular, 6mm to 8mm is preferred for the retarder oil.

In a preferred embodiment, the wire mesh may be made by deformation of a multi-layered wire braid, wherein the individual wires of the wire braid are deformed to form the filter structure. A filter structure is to be understood in the sense of the present invention as a structure in which a regular structure of a wire braid is modified into an irregular structure having an increased flow resistance for fluids such as oil and air oil mixtures.

In one embodiment, the wire mesh may have a passable area between 0.5% and 40%. Further, the wire mesh may be composed of a stainless steel braid.

In addition, it can be provided in one embodiment that the means comprise a movable part, by means of which the foam structure of the working medium can be broken up or changed.

To support foam collapse, these mechanisms may also include nozzles by which the working medium can be injected into the bleed channels.

Furthermore, it is advantageous if an oil separator is provided between the check valve and the surroundings.

The check valve and/or the mechanism may be constituted by individual components that have to be assembled or produced by a so-called additive manufacturing method, so that they form a unit.

Drawings

The invention is explained in more detail below with the aid of the figures. Wherein:

FIG. 1 shows a schematic view of an apparatus for closing an air bleed passage;

FIG. 2 illustrates an embodiment of an apparatus;

FIG. 3 shows a wire mesh;

fig. 4 shows a hydraulic circuit with an associated working medium circuit.

Detailed Description

Fig. 1 shows a schematic view of a device 2 for closing an air bleeding channel. The closed device 2 shown here comprises an oil separator 21 with an exhaust outlet 22, a check valve 16 and a wire mesh 20.

The closure device 2 comprises a non-return valve 16 which closes only on the basis of its structural design when the buoyancy of the float body 17 is sufficiently great for the float body to move into the closed position towards the sealing plane 19.

Fig. 2 shows a possible embodiment of a closure device 2, which essentially corresponds to the structure of the schematic diagram shown in fig. 1.

If for the braking mode the working medium, in particular retarder oil, is moved into the working chamber 9 of the retarder, the air comprised in the retarder working chamber 9 must be let out. Depending on the state of the oil, however, foam formation takes place in the working chamber 9 and the foam is pressed out of the working chamber via the venting channel 15, the opening of which is located in the center of the working chamber. The closing means 2 now has the task of preventing oil from entering the surroundings. The precondition for this is that the density of the working medium and/or the working medium foam transported into the float chamber 18 is so high that the float body 17 in the float chamber 18 is moved from the open position into the closed position against the sealing plane 19. According to the invention, the density of the oil foam is changed by passing it through the wire mesh 20, i.e. breaking the foam or at least breaking the foam so that large foam bubbles become small foam bubbles.

For further safety, an oil separator 21 is also provided between the check valve 16 and the surroundings.

After switching the retarder into the non-braking mode, a negative pressure arises in the working chamber, which negative pressure causes the float body 17 to move into the open position in the float chamber and ambient air to enter the working chamber 9 through the bleed passage 15 counter to the flow direction a.

In a further embodiment, not shown, in order to break up the foam and/or reduce the bubbles, a nozzle can also or additionally be provided in the air bleed channel 15, via which nozzle oil is injected into the channel, through which nozzle the bubbles are broken. Alternatively or additionally, movable components that move through the foam are also conceivable.

An embodiment of a wire mesh 20 is shown in fig. 3. The wire mesh consists of multiple layers of wire braids which are stacked on top of each other and modified to form wire mesh 20, thereby forming the filter structure presented. In order to achieve a good foam breaking effect, the wire braid should have a wire thickness of 0.01mm to 1mm, wherein the mesh width may be 4mm to 10 mm.

The number of layers of wire braid and the degree of modification to the wire mesh with filtering effect can be matched to the retarder oil used, wherein a passable area between 0.5% and 10% will lead to the best results.

Fig. 4 schematically shows a hydraulic circuit with an associated working medium circuit. The retarder 1 has a bladed rotor 3 and a bladed stator 4, wherein the bladed rotor 3 is driven by a drive train to be braked, for example a motor vehicle drive train, via a drive shaft 5. The rotor 3 and the stator 4 are accommodated in a retarder housing 6, which comprises an interface for an external working medium circuit 2, in the present case an interface for an inflow 7, which is in a conducting connection with the working chamber 9 via a working medium inlet 8, and a first return 10 and a second return 11, which are in a conducting working medium connection with the working chamber 9 via a first working medium outlet 12 and a second working medium outlet 13.

The working medium outlets 12, 13, the inflow 7 and the idle channel 24 connected to the idle pump 23 are connected to a tank, not shown here, which contains a heat exchanger.

List of reference numerals

1 retarder

2 sealing device

3 rotor

4 stator

5 drive shaft

6 retarder shell

7 inflow part

8 working medium inlet

9 working chamber

10 first return part

11 second reflux part

12 first working medium outlet

13 second working medium outlet

14 center

15 air discharge channel

16 check valve

17 float body

18 float cavity

19 sealing plane

20 wire mesh

21 oil separator

22 exhaust outlet

23 Pump

24 idle running channel

Direction of flow A