US20190211821A1

US20190211821A1 - Arrangement for a Screw Compressor of a Utility Vehicle

Info

Publication number: US20190211821A1
Application number: US16/353,755
Authority: US
Inventors: Gilles Hebrard; Jean-Baptiste Marescot; Joerg MELLAR; Thomas Weinhold
Original assignee: Knorr Bremse Systeme fuer Nutzfahrzeuge GmbH
Current assignee: Knorr Bremse Systeme fuer Nutzfahrzeuge GmbH
Priority date: 2016-09-21
Filing date: 2019-03-14
Publication date: 2019-07-11
Also published as: KR20190049862A; WO2018054876A1; CN109937302A; DE102016011444A1; JP2019532223A; CN109937302B; EP3516220A1; BR112019005101A2

Abstract

An arrangement for a screw compressor of a utility vehicle has at least one housing part of the screw compressor and a baffle. The housing component has at least three baffle receptacle recesses, wherein at least one baffle receptacle recess is arranged outside an imaginary line connecting the two other baffle receptacle recesses. The baffle has at least three fingers which, in the assembled state of the arrangement, are each inserted in a baffle receptacle recess associated with the respective finger.

Description

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of PCT International Application No. PCT/EP2017/073576, filed Sep. 19, 2017, which claims priority under 35 U.S.C. § 119 from German Patent Application No. 10 2016 011 444.4, filed Sep. 21, 2016, the entire disclosures of which are herein expressly incorporated by reference.

BACKGROUND AND SUMMARY OF THE INVENTION

The present invention relates to an arrangement for a screw compressor of a utility vehicle, comprising at least one housing component of the screw compressor and a baffle plate.
Screw compressors for utility vehicles are already known from the prior art. Such screw compressors are used, for example, to provide the compressed air required for the brake system of the utility vehicle.
In this context, in particular oil-filled compressors, in particular also screw compressors, are known, in the case of which it is necessary to regulate the oil temperature. This is generally realized by virtue of an external oil cooler being provided which is connected to the oil-filled compressor and to the oil circuit via a thermostat valve. Here, the oil cooler is a heat exchanger which has two mutually separate circuits, wherein the first circuit is provided for the hot liquid, that is to say the compressor oil, and the second circuit is provided for the cooling liquid. As cooling liquid, use may for example be made of air, water mixtures with an antifreeze, or another oil.
This oil cooler must then be connected to the compressor oil circuit by way of pipes or hoses, and the oil circuit must be safeguarded against leakage.
This external volume must furthermore be filled with oil, such that the total quantity of oil is also increased. The system inertia is thus increased. Furthermore, the oil cooler must be mechanically accommodated and fastened, either by way of brackets situated in the surroundings or by way of a separate bracket, which necessitates additional fastening means and also structural space.
U.S. Pat. No. 4,780,061 has already disclosed a screw compressor with an integrated oil cooling arrangement.
Furthermore, DE 37 17 493 A1 discloses a screw compressor installation which is arranged in a compact housing and which has an oil cooler on the electric motor of the screw compressor.
A generic screw compressor is already known for example from DE 10 2004 060 417 B4.
In order to be able to better control the movements of the oil in the screw compressor itself even during driving operation of the utility vehicle, it is desirable firstly to enable the oil to reach anywhere in the screw compressor itself for lubrication purposes but secondly to control the oil sump in terms of its movement.
It is therefore the object of the present invention to advantageously further develop an arrangement for a screw compressor of a utility vehicle of the type mentioned in the introduction, in particular such that the assembly of the screw compressor can be simplified and improved overall.
This object is achieved according to the invention by an arrangement for a screw compressor of a utility vehicle having the claimed features. Provision is made for an arrangement for a screw compressor of a utility vehicle to comprise at least one housing component of the screw compressor and a baffle plate, wherein the baffle plate is, in the assembled state, inserted in clamped fashion in the housing component.
The invention is based on the underlying concept of the fastening of the baffle plate in the housing component of the screw compressor being realized in a simple and reliable manner. This is realized in particular by virtue of the baffle plate being held with clamping action in the housing. For this purpose, a mere insertion of the baffle plate into the housing component is sufficient to permit a reliable fastening.
The housing component advantageously has at least three baffle plate receiving apertures, wherein at least one baffle plate receiving aperture is arranged outside an imaginary line which connects the two other baffle plate receiving apertures, and wherein the baffle plate has at least three fingers which, in the assembled state of the arrangement, are inserted in each case into a baffle plate receiving aperture assigned to the respective finger. Owing to the fact that the baffle plate receiving apertures are not in alignment and also do not lie on a line, this arrangement results in a bending force being exerted on the baffle plate during the insertion process, such that said baffle plate is held in clamped fashion in the housing component. The baffle plate is thus held with clamping action in the housing component and can, after being inserted into the baffle plate receiving apertures, be held securely therein owing to the bending force exerted as a result of the shaping and arrangement of the baffle plate receiving apertures. Falling out is hereby reliably prevented. Due to the fastening by way of baffle plate receiving apertures and correspondingly associated fingers in the baffle plate, simple production is made possible. Due to the insertion of the baffle plate into the baffle plate receiving apertures, the assembly process is furthermore made relatively straightforward. Even automated fitting and assembly is conceivable and possible.
Provision may furthermore be made for the housing component to be the rotor housing of the screw compressor. In this context, it is advantageous in particular for the baffle plate to be arranged below the rotors (in relation to the assembled state).
It is however basically also contemplated for the housing component to be the housing cover of the screw compressor. By inserting the baffle plate into a first housing component of the housing, such as for example the housing cover, it is made possible for the fastening to be realized only in one single housing component. Since the baffle plate is hereby already securely held, a fastening in another housing component of the housing of the screw compressor is no longer necessary. This fact self-evidently also applies analogously to an arrangement of the baffle plate and a fastening of the baffle plate in the rotor housing.
Provision may furthermore be made whereby the middle of the three baffle plate receiving apertures is arranged outside the imaginary line that connects the two other baffle plate receiving apertures. In this way, it is made possible to realize relatively simple clamping because, in the middle region, the bending force is formed which then serves for clamping of the baffle plate in the baffle plate receiving apertures or in the housing component of the screw compressor. The bending forces required for the assembly process, which can be imparted for this purpose, are furthermore relatively easy to apply because the baffle plate has to be bent in the middle, and then an insertion can be performed relatively easily.
The fingers of the baffle plate may be substantially in alignment in the non-inserted and non-assembled state. It is contemplated in particular for the baffle plate, in the non-bent state, to be a relatively simple flat non-bent or planar plate. By means of such an arrangement, inexpensive manufacture is made possible, and an easy application of the required bending forces for the insertion of the baffle plate into the housing component is achieved. In particular, provision may be made whereby the baffle plate is, in the inserted and assembled state, as a result of the insertion of the fingers into the respectively associated baffle plate receiving apertures, bent such that the baffle plate is held braced with clamping action in the housing component. By way of the braced holding with clamping action, it is reliably achieved that the baffle plate is blocked in the housing component merely as a result of the insertion of its three fingers into the associated baffle plate receiving apertures. Owing to the fact that the bending promotes the braced holding with clamping action, a self-securing holding action is achieved in this way.
The fingers of the baffle plate may all be arranged at one edge of the baffle plate. Simple manufacture is hereby achieved. For the insertion of the baffle plate in the housing component, a single movement is thus sufficient, and an additional adjustment or insertion into other housing components is not necessary.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of one or more preferred embodiments when considered in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic sectional drawing through an exemplary screw compressor according to the invention.

FIG. 2 is a perspective view of the rotor housing of the screw compressor as per FIG. 1.

FIG. 3 is a perspective view of the baffle plate as per FIG. 2.

FIG. 4 is a detailed plan view of the baffle plate receiving apertures in the rotor housing as per the exemplary embodiment in FIG. 2.

DETAILED DESCRIPTION OF THE DRAWINGS

FIG. 1 shows, in a schematic sectional illustration, a screw compressor 10 in the context of an exemplary embodiment of the present invention.
The screw compressor 10 has a fastening flange 12 for the mechanical fastening of the screw compressor 10 to an electric motor (not shown in any more detail here).
What is shown, however, is the input shaft 14, by which the torque from the electric motor is transmitted to one of the two screws 16 and 18, specifically the screw 16.
The screw 18 meshes with the screw 16 and is driven by means of the latter.
The screw compressor 10 has a housing 20 in which the main components of the screw compressor 10 are accommodated.
The housing 20 is filled with oil 22.
At the air inlet side, an inlet connector 24 is provided on the housing 20 of the screw compressor 10. The inlet connector 24 is in this case designed such that an air filter 26 is arranged at said inlet connector. Furthermore, an air inlet 28 is provided radially on the air inlet connector 24.
In the region between the inlet connector 24 and the point at which the inlet connector 24 joins to the housing 20, a spring-loaded valve insert 30 is provided, which is designed here as an axial seal.
The valve insert 30 serves as a check valve.
Located downstream of the valve insert 30, an air feed channel 32 feeds the air to the two screws 16, 18.
At the outlet side of the two screws 16, 18, an air outlet pipe 34 with a riser line 36 is provided.
In the region of the end of the riser line 36, a temperature sensor 38 is provided by which the oil temperature can be monitored.
Also provided in the air outlet region is a holder 40 for an air deoiling element 42.
In the assembled state, the holder 40 for the air deoiling element has the air deoiling element 42 in the region facing toward the base (as also shown in FIG. 1).
Also provided, in the interior of the air deoiling element 42, is a corresponding filter screen or known filter and oil separation devices 44, which will not be specified in any more detail.
In the central upper region in relation to the assembled and operationally ready state (that is to say as shown in FIG. 1), the holder for the air deoiling element 42 has an air outlet opening 46 which lead to a check valve 48 and a minimum pressure valve 50. The check valve 48 and the minimum pressure valve 50 may also be formed in one common combined valve.
The air outlet 51 is provided downstream of the check valve 48.
The air outlet 51 is generally connected to correspondingly known compressed-air consumers.
In order for the oil 22 that is situated and separated off in the air deoiling element 42 to be returned into the housing 20, a riser line 52 is provided which has a filter and check valve 54 at the outlet of the holder 40 for the air deoiling element 42 at the transition into the housing 20.
A nozzle 56 is provided, downstream of the filter and check valve 54, in a housing bore. The oil return line 58 leads back into approximately the central region of the screw 16 or of the screw 18 in order to feed oil 22 thereto again.
An oil drain screw 59 is provided in the base region, in the assembled state, of the housing 20. By means of the oil drain screw 59, a corresponding oil outflow opening can be opened, via which the oil 22 can be drained.
Also provided in the lower region of the housing 20 is the attachment piece 60 to which the oil filter 62 is fastened. Via an oil filter inlet channel 64, which is arranged in the housing 20, the oil 22 is conducted firstly to a thermostat valve 66.
Instead of the thermostat valve 66, it is possible for an open-loop and/or closed-loop control device to be provided by which the oil temperature of the oil 22 situated in the housing 20 can be monitored and set to a setpoint value.
Downstream of the thermostat valve 66, there is then the oil inlet of the oil filter 62, which, via a central return line 68, conducts the oil 22 back to the screw 18 or to the screw 16 again, and also to the oil-lubricated bearing 70 of the shaft 14. Also provided in the region of the bearing 70 is a nozzle 72, which is provided in the housing 20 in conjunction with the return line 68.
The cooler 74 is connected to the attachment piece 60, as will be discussed in more detail below in FIGS. 2 to 4.
In the upper region of the housing 20 (in relation to the assembled state), there is situated a safety valve 76, by which an excessively high pressure in the housing 20 can be dissipated.
Upstream of the minimum pressure valve 50, there is situated a bypass line 78, which leads to a relief valve 80. Via the relief valve 80, which is activated by way of a connection to the air feed 32, air can be returned into the region of the air inlet 28. In this region, there may be provided a ventilation valve (not shown in any more detail) and also a nozzle (diameter constriction of the feeding line).
Furthermore, approximately at the level of the line 34, an oil level sensor 82 may be provided in the outer wall of the housing 20. The oil level sensor 82 may for example be an optical sensor, and may be designed and configured such that, on the basis of the sensor signal, it can be identified whether the oil level during operation is above the oil level sensor 82 or whether the oil level sensor 82 is exposed, and thus the oil level has correspondingly fallen.
In conjunction with this monitoring, it is also possible for an alarm unit to be provided which outputs or transmits a corresponding error message or warning message to the user of the system.
The function of the screw compressor 10 shown in FIG. 1 is as follows.
Air is fed via the air inlet 28 and passes via the check valve 30 to the screws 16, 18, where the air is compressed. The compressed air-oil mixture, which, having been compressed by a factor of between 5 and 16 downstream of the screws 16 and 18, rises through the outlet line 34 via the riser pipe 36, and is blown directly onto the temperature sensor 38.
The air, which still partially carries oil particles, is then conducted via the holder 40 into the air deoiling element 42 and, if the corresponding minimum pressure is attained, passes into the air outlet line 51.
The oil 22 situated in the housing 20 is kept at operating temperature via the oil filter 62 and possibly via the heat exchanger 74.
If no cooling is necessary, the heat exchanger 74 is not used and is also not activated.
The corresponding activation is performed by way of the thermostat valve 66. After purification in the oil filter 64, oil is fed via the line 68 to the screw 18 or to the screw 16, and also to the bearing 72. The screw 16 or the screw 18 is supplied with oil 22 via the return line 52, 58, and the purification of the oil 22 takes place here in the air deoiling element 42.
By use of the electric motor (not shown in any more detail), which transmits its torque via the shaft 14 to the screw 16, which in turn meshes with the screw 18, the screws 16 and 18 of the screw compressor 10 are driven.
By use of the relief valve 80 (not shown in any more detail), it is ensured that the high pressure that prevails for example at the outlet side of the screws 16, 18 in the operational state cannot be enclosed in the region of the feed line 32, and that, instead, in particular during the start-up of the compressor, there is always a low inlet pressure, in particular atmospheric pressure, prevailing in the region of the feed line 32. Otherwise, upon a start-up of the compressor, a very high pressure would initially be generated at the outlet side of the screws 16 and 18, which would overload the drive motor.
FIG. 2 shows, in a perspective view, the arrangement for the screw compressor 10 of the utility vehicle having the at least one housing component, in this case the rotor housing 20 a, and the baffle plate 100.
Here, the baffle plate 100 has been inserted into the rotor housing 20 a.
It is basically also contemplated that the housing cover of the screw compressor 10 may also be used instead of the rotor housing 20 a. In the inserted and assembled state as shown in FIG. 2, the baffle plate 100 has been bent as a result of the insertion into the rotor housing 20 a, such that the baffle plate 100 is held braced with a clamping action in the rotor housing 20 a.
For this purpose, as shown in FIGS. 3 and 4, it is firstly the case that fingers 102, specifically three fingers 102, are arranged on one side on the baffle plate 100.
Secondly, the rotor housing 20 a has three baffle plate receiving apertures 104.
Here, the baffle plate receiving apertures 104 are arranged such that the two outer baffle plate receiving apertures 104 form a line, and the third baffle plate receiving aperture 104 is arranged offset in relation to that line. The three baffle plate receiving apertures 104 are thus not in alignment.
In other words, the middle of the three baffle plate receiving apertures 104 is arranged outside the imaginary line that connects the two other baffle plate receiving apertures 104.
By use of the fingers 102, the baffle plate 100 is inserted into the baffle plate receiving apertures 104.
This holding with clamping action is sufficient to securely fasten the baffle plate 100 in the rotor housing 20 a.
Due to the offset of the middle baffle plate receiving aperture 104, the baffle plate 100 is, owing to its stiffness, held firstly in bent fashion but also with a self-securing action, because the bending force that is furthermore exerted and the arrangement of the fingers 102 ensure that the baffle plate 100 is held braced with clamping action in the rotor housing 20 a by way of its fingers 102 in the baffle plate receiving apertures 104 of the rotor housing 20 a.

LIST OF REFERENCE SIGNS

10 Screw compressor
12 Fastening flange
14 Input shaft
16 Screw
18 Screw
20 Housing
20 a Rotor housing
22 Oil
24 Inlet connector
26 Air filter
28 Air inlet
30 Valve insert
32 Air feed channel
34 Air outlet pipe
36 Riser line
38 Temperature sensor
40 Holder for an air deoiling element
42 Air deoiling element
44 Filter screen or known filter or oil separation devices
46 Air outlet opening
48 Check valve
50 Minimum pressure valve
51 Air outlet
52 Riser line
54 Filter and check valve
56 Nozzle
58 Oil return line
59 Oil drain screw
60 Attachment piece
62 Oil filter
64 Oil filter inlet channel
66 Thermostat valve
68 Return line
70 Bearing
72 Nozzle
76 Safety valve
78 Bypass line
80 Relief valve
82 Oil level sensor
100 Baffle plate
102 Finger
104 Baffle plate receiving apertures

The foregoing disclosure has been set forth merely to illustrate the invention and is not intended to be limiting. Since modifications of the disclosed embodiments incorporating the spirit and substance of the invention may occur to persons skilled in the art, the invention should be construed to include everything within the scope of the appended claims and equivalents thereof.

Claims

What is claimed is:

1. An arrangement for a screw compressor of a utility vehicle, comprising:

at least one housing component of the screw compressor; and

a baffle plate, wherein

the baffle plate is, in an assembled state, inserted in a clamped fashion in the housing component.

2. The arrangement as claimed in claim 1, wherein

the housing component has at least three baffle plate receiving apertures,

at least one baffle plate receiving aperture is arranged outside an imaginary line which connects the two other baffle plate receiving apertures, and

the baffle plate has at least three fingers which, in the assembled state of the arrangement, are inserted in each case into a baffle plate receiving aperture assigned to the respective finger.

3. The arrangement as claimed in claim 2, wherein

the housing component is a rotor housing of the screw compressor.

4. The arrangement as claimed in claim 2, wherein

the housing component is a housing cover of the screw compressor.

5. The arrangement as claimed in claim 2, wherein

a middle one of the three baffle plate receiving apertures is arranged outside the imaginary line that connects the two other baffle plate receiving apertures.

6. The arrangement as claimed in claim 2, wherein

the fingers of the baffle plate are substantially in alignment in a non-inserted and non-assembled state.

7. The arrangement as claimed in claim 2, wherein

the baffle plate is, in the inserted and assembled state, as a result of the insertion of the fingers into the respectively associated baffle plate receiving apertures, bent such that the baffle plate is held braced with the clamping action in the housing component.

8. The arrangement as claimed in claim 2, wherein

the fingers of the baffle plate are all arranged at one edge of the baffle plate.