GB1597223A - Air compressing apparatus - Google Patents

Description

(54) IMPROVEMENTS IN AIR COMPRESSING APPARATUS (71) We, COMPAIR INDUSTRIAL LIMITED, a British Company, of P.O. Box 7, Broomwade Works, High Wycombe, Buckinghamshire, HP13 5SF and SIDNEY JOHN MORRIS, a British Subject, of 30, Willow Avenue, Booker, High Wycombe, Buckinghamshire, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement:: The invention relates to air compressing apparatus and provides air compressing apparatus comprising a framework, a motive power producing means supported by the framework and having a rotary output shaft generally vertical, an air compressor supported by the framework generally vertically above the said means and drivably connected to the output shaft thereof, and a fan arranged between the said means and the compressor and also driven by the said means, said fan being arranged, in use, to circulate cooling air over at least the said means, the enclosure is divided into three compartments, a first compartment in which the compressor is located, a second compartment in which the fan is located and a third compartment in which the motive power producing means is located, air inlet apertures being provided in the first and third compartments.

Preferably the fan is a double sided fan arranged, in use, to circulate air over both the motive power producing means and the compressor.

The motive power producing means may be an electric motor and the fan may be directly coupled to the output shaft of the motor. The compressor may be a screw compressor or other rotary compressor and the compressor input shaft may be coupled to the side of the fan remote from the output shaft of the motor by a parallel shaft gear train.

It will be appreciated that the above described arrangement of air compressing apparatus, arranged generally vertically with the compressor above the motive power producing means enables a compressor package to be produced which occupies considerably less floor space than similar apparatus arranged in known manner generally horizontally.

A preferred embodiment of air compressing apparatus according to the invention will now be described by way of example, with reference to the accompanying drawings, in which: Figure I is a vertical section through air compressing apparatus according to the invention, and Figure 2 is an enlarged detail of part of the apparatus of Figure 1.

As shown in Figure 1, air compressing apparatus comprising a compressor 10, a fan 11 and a motive power producing means, in this case an electric motor, 12 is arranged within an enclosure generally indicated by 13.

The output shaft 15 of the motor 12 is connected to one side of the fan 11, which is a double-sided fan, by a flexible coupling 16. The fan 11 is mounted on a shaft 18 which is supported in bearings 19, 20, said shaft extending above the fan co-axially with output shaft 15. A drive gear 22 is fixed on the shaft 18 and meshes with an input gear 23 of the compressor 10.

The compressor illustrated is an oilinjected meshing-screw compressor 10 with axial flow but it will be appreciated that any type of rotary piston compressor may be used. The compressor rotors (not shown) are located within a compressor casing 25 which is in turn located within a compressor housing 26. The compressor housing is mounted on a support structure 28 which includes the compressor bearing housing 29, a reservoir 30 for the compressor lubricating oil and the inlet ducting 31 (see Figure 2) for the compressor. A bearing 19 is located in the housing 29 and another bearing 20 is located in a bearing housing formed in a lower portion of the support structure 28.

The compressor rotor shaft (not shown) extends through tbe bearing housing 29 and carries the input gear 23, and the teeth ratio of gears 22, 23 is chosen to produce the required compressor shaft speed for a given motor shaft speed.

The compressor support structure 28 is mounted on a central support structure 33 which encloses the periphery of the fan and on which the motor 12 is suspended, the assembly being mounted on a framework 34 by anti-vibration pads 35. The support structures 28, 33 and the motor 12 are positioned by spigots or similar means, so that the motor, fan and compressor axes are aligned and generally vertical. The base 36 of the framework 34 rests on the ground.

Heat exchangers 38 are mounted on the central support structure 33 around the periphery of the fan and are cooled by the fan, the air leaving the fan being directed onto the heat exchangers by the support structure 33.

The enclosure 13 for noise insulation, dirt protection, weather proofing etc., fits over the apparatus described above and is supported by the framework 34. The enclosure 13 may comprise a unit construction box or may be constructed from a number of panels bolted, hinged or otherwise secured to the framework. The enclosure may include inspection doors (not shown) and windows (not shown) for viewing the operating dials of the compressor and motor.

The enclosure 13 is divided into first, second and third compartments 41, 42, 43 respectively enclosing the compressor 10, fan 11 and motor 12 by bulkheads 44, 45 attached to or in sealing abutment with the outer faces of the heat exchangers 38 and the inner face of the enclosure 13. The bulkheads define between them an annular space around the periphery of compartment 42 which serves to duct the spent cooling air from the enclosure through an outlet aperture 47. The outlet aperture may be connected to further ducting for utilisation of the warmed air leaving the enclosure.

Baffled inlet apertures 49, 50 for the cooling air are provided in the upper 41 and lower 43 compartments respectively.

In use, air from the atmosphere is drawn into the upper and lower compartments 41, 43 through apertures 49, 50 by the action of fan 11. The fan 11 causes air thus drawn in to circulate around the compressor 10 and motor 12 respectively, thereby to cool these devices and any associated equipment within compartments 41, 43. The cooling air is eventually drawn into the central fan 11 and then blown out into the outlet duct 47 via heat exchangers 38.

Air drawn in through aperture 49 also supplies the compressor inlet duct 53 via an air filter (not shown) and a flow regulator (not shown). The various air flow paths described above are indicated in Figure 1 by dotted arrows.

The compressor casing 25, housing 29 and support structure 28 also include flow paths for lubricating oil. Cooled air from heat exchangers 38 flows through return pipe 64 and bores 55, 56, 57 to lubricate the rotors of the compressor and, in spray form, the drive gears 22, 23. Lubricating oil from the gears 22, 23 drains by gravity into a well 60 in the bottom of structure 28 whence it is transferred to the compressor inlet duct 31 via a syphon pipe 58. The oil is transferred up the syphon pipe by the inherent depression in the inlet duct 31, the space around the gears being vented to atmosphere by a hole (not shown) to ensure a pressure drop between this space and the inlet duct 31.

Oil passing up the syphon pipe 58, together with oil lubricating the rotors of the compressor is entrained in the air passing through the compressor and is discharged with the compressed air into housing 26.

The oil is cleared from the compressed air by a deflector means 61 and a porous filter 62 and drains to the bottom of the housing 26 thence into oil reservoir 30 and via pipe 63 to heat exchanger 38. The pressure within the housing forces the oil through heat exchanger 38, up pipe 64 to an oil filter 65, thus providing cooled oil to the duct 55 again.

The cleaned compressed air is piped out of the housing 26 to the user via pipe 67.

The air may leave the enclosure via an aftercooler mounted with heat exchangers 38 on the central support structure 33 or may be taken to an external aftercooler.

The cooled air may thereafter be piped through a separator to remove moisture and the separator may be housed within compartment 43 of the enclosure or externally.

The air compressing apparatus described above provides a unit of compact size occupying less floor space than conventional horizontally mounted apparatus. Moreover the unit may facilitate use, inspection and maintenance of the apparatus since dials, inspection hatches, etc. may all be sited at a convenient height from the floor.

WHAT WE CLAIM IS: 1. Air compressing apparatus comprising a framework, a motive power producing means supported by the framework and having a rotary output shaft generally vertical, an air compressor supported by the framework generally vertically above the said means and drivably connected to the

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (9)

**WARNING** start of CLMS field may overlap end of DESC **. a reservoir 30 for the compressor lubricating oil and the inlet ducting 31 (see Figure 2) for the compressor. A bearing 19 is located in the housing 29 and another bearing 20 is located in a bearing housing formed in a lower portion of the support structure 28. The compressor rotor shaft (not shown) extends through tbe bearing housing 29 and carries the input gear 23, and the teeth ratio of gears 22, 23 is chosen to produce the required compressor shaft speed for a given motor shaft speed. The compressor support structure 28 is mounted on a central support structure 33 which encloses the periphery of the fan and on which the motor 12 is suspended, the assembly being mounted on a framework 34 by anti-vibration pads 35. The support structures 28, 33 and the motor 12 are positioned by spigots or similar means, so that the motor, fan and compressor axes are aligned and generally vertical. The base 36 of the framework 34 rests on the ground. Heat exchangers 38 are mounted on the central support structure 33 around the periphery of the fan and are cooled by the fan, the air leaving the fan being directed onto the heat exchangers by the support structure 33. The enclosure 13 for noise insulation, dirt protection, weather proofing etc., fits over the apparatus described above and is supported by the framework 34. The enclosure 13 may comprise a unit construction box or may be constructed from a number of panels bolted, hinged or otherwise secured to the framework. The enclosure may include inspection doors (not shown) and windows (not shown) for viewing the operating dials of the compressor and motor. The enclosure 13 is divided into first, second and third compartments 41, 42, 43 respectively enclosing the compressor 10, fan 11 and motor 12 by bulkheads 44, 45 attached to or in sealing abutment with the outer faces of the heat exchangers 38 and the inner face of the enclosure 13. The bulkheads define between them an annular space around the periphery of compartment 42 which serves to duct the spent cooling air from the enclosure through an outlet aperture 47. The outlet aperture may be connected to further ducting for utilisation of the warmed air leaving the enclosure. Baffled inlet apertures 49, 50 for the cooling air are provided in the upper 41 and lower 43 compartments respectively. In use, air from the atmosphere is drawn into the upper and lower compartments 41, 43 through apertures 49, 50 by the action of fan 11. The fan 11 causes air thus drawn in to circulate around the compressor 10 and motor 12 respectively, thereby to cool these devices and any associated equipment within compartments 41, 43. The cooling air is eventually drawn into the central fan 11 and then blown out into the outlet duct 47 via heat exchangers 38. Air drawn in through aperture 49 also supplies the compressor inlet duct 53 via an air filter (not shown) and a flow regulator (not shown). The various air flow paths described above are indicated in Figure 1 by dotted arrows. The compressor casing 25, housing 29 and support structure 28 also include flow paths for lubricating oil. Cooled air from heat exchangers 38 flows through return pipe 64 and bores 55, 56, 57 to lubricate the rotors of the compressor and, in spray form, the drive gears 22, 23. Lubricating oil from the gears 22, 23 drains by gravity into a well 60 in the bottom of structure 28 whence it is transferred to the compressor inlet duct 31 via a syphon pipe 58. The oil is transferred up the syphon pipe by the inherent depression in the inlet duct 31, the space around the gears being vented to atmosphere by a hole (not shown) to ensure a pressure drop between this space and the inlet duct 31. Oil passing up the syphon pipe 58, together with oil lubricating the rotors of the compressor is entrained in the air passing through the compressor and is discharged with the compressed air into housing 26. The oil is cleared from the compressed air by a deflector means 61 and a porous filter 62 and drains to the bottom of the housing 26 thence into oil reservoir 30 and via pipe 63 to heat exchanger 38. The pressure within the housing forces the oil through heat exchanger 38, up pipe 64 to an oil filter 65, thus providing cooled oil to the duct 55 again. The cleaned compressed air is piped out of the housing 26 to the user via pipe 67. The air may leave the enclosure via an aftercooler mounted with heat exchangers 38 on the central support structure 33 or may be taken to an external aftercooler. The cooled air may thereafter be piped through a separator to remove moisture and the separator may be housed within compartment 43 of the enclosure or externally. The air compressing apparatus described above provides a unit of compact size occupying less floor space than conventional horizontally mounted apparatus. Moreover the unit may facilitate use, inspection and maintenance of the apparatus since dials, inspection hatches, etc. may all be sited at a convenient height from the floor. WHAT WE CLAIM IS:

1. Air compressing apparatus comprising a framework, a motive power producing means supported by the framework and having a rotary output shaft generally vertical, an air compressor supported by the framework generally vertically above the said means and drivably connected to the

output shaft thereof, and a fan arranged between the said means and the compressor and also driven by the said means, said fan being arranged, in use, to circulate cooling air over at least the said means, the enclosure is divided into three compartments, a first compartment in which the compressor is located, a second compartment in which the fan is located and a third compartment in which the motive power producing means is located, air inlet apertures being provided in the first and third compartments.

2. Apparatus as claimed in claim 1 in which the fan is a double-sided fan arranged, in use, to circulate air over both the motive power producing means and the compressor.

3. Apparatus as claimed in claim 1 or claim 2 in which the motive power producing means is an electric motor and the fan is directly coupled to the output shaft of the motor.

4. Apparatus as claimed in claim 3 in which an input shaft of the compressor is coupled to the side of the fan remote from the output shaft of the motor by a parallel shaft gear train.

5. Apparatus as claimed in any one of the preceding claims in which the compressor is an oil-injected screw compressor.

6. Apparatus as claimed in claim 5 in which a perhiperal heat exchanger surrounds the periphery of the fan and lubricating oil for the compressor is cooled, in use, by passage through the heat exchanger.

7. Apparatus as claimed in claim 6 in which the compressor comprises a housing which includes an oil reservoir, and which housing includes a passage for cooled oil from the heat exchanger to the compressor parts to be lubricated.

8. Apparatus as claimed in claim 5 when dependent on claim 4 in which the gear train is enclosed in a casing including a connection to the air inlet of the compressor whereby a suction is applied to the casing, the arrangement being such that, in use, lubricating oil is scavenged from the casing and flows to the air inlet against the action of gravity, due to the suction.

9. Air compressing apparatus substantially as hereinbefore described with reference to and as shown in the accompanying drawings.