JP6835974B2 - Systems for commercial vehicles, including screw compressors and electric motors - Google Patents

Description

The present invention relates to systems for commercial vehicles, including screw compressors and electric motors.

A screw compressor for commercial vehicles is already known by the prior art. This type of screw compressor is used, for example, to prepare the compressed air required for a commercial vehicle braking system.

In this connection, an oil-filled compressor, particularly a screw compressor, is also known, and control of the oil temperature is an issue in such a compressor. Control of the oil temperature is usually carried out by providing an external oil cooler connected to the oil-filled compressor and oil circulation path via a temperature control valve. In this case, the oil cooler is a heat exchanger having two circulation paths separated from each other, and is a high temperature fluid, that is, a first circulation path for compressor oil and a second circulation path for cooling fluid. Is provided. As the cooling fluid, for example, air, mixed water containing an antifreeze agent, or other oil can be used.

The oil cooler must then be connected to the compressor oil circulation via a conduit or hose, and the oil circulation must be protected against leaks.

In addition, this external volume must be filled with oil, which also increases the total amount of oil. This increases the system inertia. In addition, the oil cooler must be mechanically housed and mounted by a surrounding retainer, or a separate retainer, which also requires additional mounting means and thus configuration space. To do.

US Pat. No. 4,780,601 (US 4,780,061) already knows a screw compressor with an incorporated oil cooler.

Further, German Patent Application Publication No. 3717493 (DE 37 17 493 A1) discloses a screw compressor device arranged in a compact casing, and this screw compressor device is a screw compressor. It has an oil cooler on the electric motor.

According to German Patent Application Publication No. 102010015151 (DE 10 2010 015 151 A1), compressor flanges for screw compressors are known.

Further, US Patent Application Publication No. 201401090674 (US 2014/0190674 A1) discloses a connecting flange with a cooling passage for an automobile heat exchanger.

Further, according to German Patent Invention No. 102013011061 (DE 10 2013 011 061 B3), a heat exchanger provided with a flange connection portion is known, and this flange connection portion is a die casting component and houses a screw pin. Has a connecting flange with through holes manufactured by casting technology for.

An object of the present invention is to be able to improve systems for commercial vehicles, including screw compressors and electric motors, to provide space-saving cooling means, especially for the types of systems mentioned at the outset. That is.

According to the present invention, this problem is solved by a system for a commercial vehicle including a screw compressor and an electric motor, which has the feature of claim 1. According to this, the system for commercial vehicles includes a screw compressor and an electric motor, the electric motor drives the screw compressor, the electric motor is connected to the screw compressor by a flange, and this flange has at least one cooling. It has a connection, and the flange is provided with at least one cooling passage.

The idea underlying the present invention is that a space-saving cooling means is provided by providing a cooling connection element between the screw compressor and the electric motor. This no longer requires air cooling of the electric motor and screw compressor. Rather, it provides the potential for on-target cooling directly where the system's main heat generation is present. The placement of a flange between the electric motor and the screw compressor, as well as the fact that the flange is provided with at least one cooling passage, can allow cooling with a suitable cooling fluid.

In particular, the flange may be a separate component. This allows the corresponding cooling passage geometry to be easily provided on the flange. The screw compressor and electric motor can, in this case, be formed or remain standard with respect to the mechanical interface, i.e. the corresponding flange, without the need for modification.

Within the flange, a drive shaft for driving the screw compressor by an electric motor may be guided. Therefore, the heat generated there can be easily derived through the flange.

The cooling fluid for the flange may be an aqueous cooling fluid, in particular cooling water, or a mixture of water and another component, such as methylene glycol, or other suitable antifreeze. Good.

In addition, screw compressors may be used to form compressed air. Especially in this case, this may be a screw compressor used to supply compressed air to a commercial vehicle pneumatic braking device. By providing a screw compressor equipped with an electric motor, such a type of system can be used in a hybrid vehicle in the commercial vehicle field. It is possible to provide an efficient system.

The electric motor may have an electric motor flange provided for connection with the flange. In this case, the electric motor flange may be a standard formed electric motor flange of the electric motor. Therefore, no adaptation is required, which allows cheaper means.

In particular, the flange cooling passage may be opened in the direction of the electric motor flange in the assembled state. This allows direct contact between the cooling fluid and at least the portion of the electric motor flange. As a result, heat can be effectively discharged from the electric motor through the electric motor flange and the cooling fluid in the cooling passage of the flange.

Sealing of the cooling passage can be realized only in the assembled state by assembling the electric motor flange and the flange. As easily achieved by this, the cooling fluid should and can be in direct contact with at least the portion of the electric motor flange in the assembled state of the system.

In particular, the electric motor may also not have a separate cooling passage and / or refrigerant connection. This ensures that the electric motor does not require any special adaptation, which allows for inexpensive manufacturing and assembly of the system.

Further details and advantages of the present invention will be described in detail with reference to the illustrated examples.

FIG. 5 is a cross-sectional view schematically showing an embodiment of the present invention for a system according to the present invention for commercial vehicles, including a screw compressor and an electric motor. It is a perspective view which shows the system in the assembled state. It is a perspective view which shows the flange between a screw compressor and an electric motor. It is a perspective view which shows the flange between a screw compressor and an electric motor.

FIG. 1 shows a schematic cross-sectional view of the screw compressor 10 according to the embodiment of the present invention.

The screw compressor 10 has a mounting flange 12 for mechanically mounting the screw compressor 10 to an electric motor (not shown here).

However, an input shaft 14 is shown, through which torque is transmitted from the electric motor to one of both screws 16 and 18, i.e. to the screw 16.

The screw 18 meshes with the screw 16 and is driven by the screw 16.

The screw compressor 10 has a casing 20, and the main components of the screw compressor 10 are housed in the casing.

The casing 20 is filled with oil 22.

An inlet pipe piece 24 is provided on the air inlet side of the casing 20 of the screw compressor 10. In this case, the inlet pipe piece 24 is formed so that the air filter 26 is arranged on the inlet pipe piece. Further, the air inlet pipe piece 24 is provided with an air inlet 28 in the radial direction.

A spring-loaded valve insert 30 is provided in the area between the inlet tube piece 24 and the location where the inlet tube piece 24 is attached to the casing 20, in which case it is configured as an axial seal. Has been done.

Such a valve insert 30 functions as a check valve.

An air supply passage 32 for supplying air to both screws 16 and 18 is provided downstream of the valve insert 30.

An air outlet pipe 34 provided with an ascending pipe 36 is provided on the outlet side of both screws 16 and 18.

A temperature sensor 38 is provided in the region at the end of the riser pipe 36, and the oil temperature can be monitored by this temperature sensor.

Further, the air outlet region is provided with a holder 40 for the air / oil separation element 42.

The holder 40 for the air / oil separation element has the air / oil separation element 42 in the bottom area in the assembled state (as shown in FIG. 1).

Further, a corresponding filter screen or a known filtration and oil separation device 44 is provided inside the air / oil separation element 42, but this is not described in more detail.

The holder 40 for the air / oil separation element has an air outlet opening 46 in the central upper region with respect to the assembled and ready to operate state (ie, as shown in FIG. 1). Is connected to the check valve 48 and the minimum pressure valve 50. The check valve 48 and the minimum pressure valve 50 may be formed as one common valve combined.

Following the check valve 48, an air outlet 51 is provided.

The air outlet 51 is usually connected to a correspondingly known compressed air consumer.

An ascending line 52 is provided to guide the separated oil 22 existing in the air / oil separating element 42 back into the casing 20 again, and this ascending line is the air / oil separating element 42. A filtration and check valve 54 is provided at a location starting from the holder 40 and moving into the casing 20.

Downstream of the filtration and check valve 54, a nozzle 56 is provided in the casing hole. The oil return guide line 58 is returned to the substantially central region of the screw 16 or screw 18 to supply the oil 22 to the screw again.

An oil discharge screw 59 is provided in the bottom surface region of the casing 20 in the assembled state. A corresponding oil discharge opening is opened through the oil discharge screw 59, and the oil 22 can be discharged through this opening.

An attachment portion 60 to which the oil filter 62 is attached is also provided in the lower region of the casing 20. The oil 22 is first guided to the temperature control valve 66 via the oil filter inlet passage 64 arranged in the casing 20.

Instead of the temperature control valve 66, an open-loop controller and / or a closed-loop controller that can monitor the oil temperature of the oil 22 in the casing 20 and adjust it to a target value may be provided. ..

Next, downstream of the temperature control valve 66 is the oil inlet of the oil filter 62, which returns the oil 22 back to the screw 18 or back to the screw 16 via the central return guide line 68. Although it is guided, it is also guided back to the oil-lubricated bearing 70 of the shaft 14. A nozzle 72 is also provided in the region of the bearing 70, and this nozzle is provided in the casing 20 so as to communicate with the return guide pipe line 68.

The cooler 74 is connected to the attachment portion 60.

In the upper region (with respect to the assembled state) of the casing 20, a safety valve 76 capable of reducing an excessively high pressure in the casing 20 is located.

A bypass line 78 leading to the pressure release valve 80 is located in front of the minimum pressure valve 50. Air can be returned and guided to the region of the air inlet 28 through the pressure release valve 80, which is controlled by the connection with the air supply passage 32. An air vent valve and nozzle (reduced diameter portion of the supply line) not shown may be provided in this area.

Further, the oil level sensor 82 can be provided on the outer wall of the casing 20 at substantially the height of the pipeline 34. The oil level sensor 82 may be, for example, an optical sensor, and the sensor signal indicates whether the oil level is above the oil level sensor 82 during operation, or the oil level sensor 82 is exposed, thereby causing oil. It is configured and adjusted to be able to detect if the surface is correspondingly lowered.

In connection with such monitoring, an alarm unit may be provided to issue or convey appropriate error notification or warning to the user of the system.

The functions of the screw compressor 10 shown in FIG. 1 are as follows:
The air is supplied via the air inlet 28 and reaches the screws 16 and 18 via the check valve 30, where the air is compressed. The air-oil mixture compressed 5 to 16 times, after leaving the screws 16 and 18, rises through the outlet pipe 34 through the rising pipe 36 and is directly blown to the temperature sensor 38.

The air, still partially containing oil particles, is then guided through the holder 40 to the air / oil separation element 42 and reaches the air outlet line 51 when the corresponding minimum pressure is reached.

The oil 22 present in the casing 20 is held at the operating temperature via the oil filter 62 and, in some cases, through the heat exchanger 74.

If cooling is not required, the heat exchanger 74 is not used and is not turned on.

The corresponding switch-on is done via the temperature control valve 66. After purification in the oil filter 62, the oil is supplied to the screw 18 or screw 16 via the pipeline 68, but also to the bearing 70. Oil 22 is supplied to the screw 16 or screw 18 via the return guide pipes 52 and 58, in which case the purification of the oil 22 is performed in the air / oil separation element 42.

The torque of an electric motor (not shown) is transmitted to the screw 16 via the shaft 14, and the screw 16 meshes with the screw 18, and the screws 16 and 18 of the screw compressor 10 are driven via the electric motor. ..

Based on the pressure release valve 80 (not shown in detail), the high pressure formed on the outlet side of the screws 16 and 18 in the operating state is not confined in the region of the supply pipe line 32, and is supplied especially when the compressor is started. It is guaranteed that there is always a low inlet pressure, especially atmospheric pressure, in the region of the pipeline 32. Otherwise, the start of the compressor may first generate an extremely high pressure on the outlet side of the screws 16 and 18, which overloads the drive motor.

FIG. 2 is a perspective view showing an embodiment of the entire system 1 according to the present invention, which includes an electric motor 5 and a screw compressor 10.

3a and 3b are perspective views showing a flange 12 between the screw compressor 10 and the electric motor 5.

The flange 12 is located in the center as a connection portion between the screw compressor 10 and the electric motor 5.

In this case, the flange 12 is formed as a separate component arranged between the screw compressor 10 and the electric motor 5.

In this case, the drive shaft 14 is guided through the central opening 100 of the flange 12.

The flange 12 has a cooling passage 102.

The cooling passage 102 of the flange 12 is open in the direction of the electric motor flange with respect to the assembled arrangement, as can also be seen in detail in FIG. 3a.

The seal of the cooling passage 102 is formed in the assembled state only when the electric motor flange and the flange 12 are assembled.

The electric motor 5 or the electric motor flange does not have a cooling passage and a refrigerant connection.

Further, as shown in FIG. 2, generally, the refrigerant of the cooling system of the screw compressor 10 is used and circulated through the cooling passage 102 (see FIG. 3a) of the flange 12 to the cooling connections 104 and 106. It is guided to the oil cooler 74 via the connected rubber hose 108.

After oil cooling, the cooling fluid is returned to the vehicle's cooling circulation path (not shown) for which it is appropriately connected via the cooling / discharging connection 110.

1 System 5 Electric motor 10 Screw compressor 12 Mounting flange 14 Input shaft 16 Screw 18 Screw 20 Casing 22 Oil 24 Inlet pipe piece 26 Air filter 28 Air inlet 30 Valve insert 32 Air supply passage 34 Air outlet pipe 36 Rising pipe 38 Temperature sensor 40 Holder for Air / Oil Separation Element 42 Air / Oil Separation Element 44 Filter Screen or Known Filter or Oil Separator 46 Air Outlet Opening 48 Check Valve 50 Minimum Pressure Valve 51 Air Outlet 52 Rising Pipeline 54 Filtering and Reverse Stop valve 56 Nozzle 58 Oil return guide line 59 Oil discharge screw 60 Attachment 60a Outer ring 60b Inner ring 62 Oil filter 64 Oil filter inlet passage 66 Temperature control valve 68 Return guide line 70 Bearing 72 Nozzle 74 Cooler, heat exchanger 76 Safety valve 78 Bypass pipeline 80 Pressure release valve 82 Oil level sensor 100 Center opening 102 Cooling passage 104 Cooling connection part 106 Cooling connection part 108 Rubber hose 110 Cooling discharge connection part

Claims (7)

A system (1) for a commercial vehicle including a screw compressor (10) and an electric motor (5), wherein the electric motor (5) drives the screw compressor (10) by a drive shaft, and the electric motor (5). 5) is connected to the screw compressor (10) by a flange (12), the flange (12) has at least one cooling connection (104, 106), and the flange (12) has at least one cooling connection. , A screw compressor (10) and an electric motor (5) provided with a central opening (100) through which the drive shaft penetrates and at least one cooling passage formed around the central opening (100). ) only contains,
The electric motor (5) has an electric motor flange provided for connection with the flange (12), and the seal of the cooling passage assembles the electric motor flange and the flange (12). For the first time, it is formed in the assembled state,
System for commercial vehicles (1). The system (1) of claim 1, wherein the flange (12) is a separate element located between the electric motor (5) and the screw compressor (10). The system (1) according to claim 1 or 2, wherein a drive shaft for driving the screw compressor (10) is guided by the electric motor (5) in the flange (12). The system (1) according to any one of claims 1 to 3, wherein the cooling fluid for the flange (12) is aqueous. The system (1) according to any one of claims 1 to 4, wherein the screw compressor (10) is a screw compressor (10) for forming compressed air. The system (1) according to any one of claims 1 to 5 , wherein the at least one cooling passage of the flange (12) is open in the direction of the electric motor flange with respect to the assembled arrangement. The system (1) according to any one of claims 1 to 6 , wherein the electric motor (5) or the electric motor flange does not have a cooling passage and / or a refrigerant connection.

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