GB2097861A

GB2097861A - Rotary air-compressor

Info

Publication number: GB2097861A
Application number: GB8208746A
Authority: GB
Original assignee: MGM SpA
Current assignee: MGM SpA
Priority date: 1981-04-01
Filing date: 1982-03-25
Publication date: 1982-11-10
Also published as: IT1205440B; FR2503278A1; IT8105140A0; ES8302860A1; DE3209804C2; ES511001A0; DE3209804A1

Abstract

Air-compressing apparatus comprises a compressor unit (1) of the sliding-vane type, means for lubricating the compressor unit, an oil and compressed air tank (2), an oil- removing filter (3), a valve (23) for controlling the minimum operating pressure, a valve (24) for the discharge of air to the atmosphere, means including a tube (18) for the recovery and recycling of oil collected on the base of the filter (3), and a valve (26), Fig. 3 (not shown), for controlling the operation of the compressor. Additionally, a single load-bearing body (4) is provided which comprises a first portion both defining a chamber (6) for the vaned rotor (7) of the compressor unit and supporting a drive device e.g. an electric motor, (9) for the rotor (7) and a second portion defining a chamber (16) for the oil-removing filter (3). The valves, the oil-removing filter, end the oil/air tank are coaxial with one another but at different levels. <IMAGE>

Description

SPECIFICATION Blade-type rotary air compressor The present invention relates to a bladed rotary air compressor with blades which comprises, an air compressor unit, an air/oil tank, an oil filter to separate the oil utilised for lubricating the rotor of the compressor from the compressed air before the latter is dispatched for use and accessory means for controlling the minimum operating pressure, the discharge of air to atmosphere, the recovery and recycling of the oil collecting at the bottom of the filter and means for controlling the entire unit.

Various embodiments of air compressors of this general type are already known. However, such arrangements have the disadvantage that they include a considerable number of parts which require interconnection and therefore involve complicated machining and assembly procedures.

This, obviously, adversely affects production times and costs. In such known embodiments, there are appreciable head losses which reduce the capacity and efficiency of the compressor due to the relative disposition of the component parts and the fact that they must be connected together by means of conduits.

In adition to this disadvantage, the various means utilised for controlling known air compressors are not always easily accessible and cannot easily be dismantled for maintenance purposes. It is often necessary to remove other parts for this purpose. This necessitates the availability of skilled labour for such maintenance.

The present invention therefore seeks to provide a blade-type air compressor having a smaller number of components organised in a simpler and more rational manner than most, if not all, known compressors so as to permit easier and more compact assembly of the compressor and more convenient accessibility for all maintenance operations and/or the replacement of parts.

The invention also seeks to provide a bladetype air compressor in which the compressor unit, the oil/air tank and the oil-removing filter are associated directly with one another in a single housing so that the need for additional conduits is eliminated, thereby reducing the head loss and improving the efficiency of the compressor with respect to known compressors.

According to the present invention, there is provided a bladed rotary air compressor comprising a compressor unit means of lubricating the compressor unit, an oil/air tank, an oilremoving filter and accessory devices for controlling the minimum operating pressure, the discharge of air to atmosphere, the recovery and recycling of oil retained on the base of the oilremoving filter and the overall operation of the compressor wherein a single load-bearing body is provided which comprises a first portion forming a stator or housing defining a chamber for the bladed rotor of the compressor unit and means for supporting a drive device for the compressor unit and a second portion defining a chamber for the oil-removing filter and the control components, the oil-removing filter and the oil/air tank being coaxial with one another but being disposed at different levels.

Preferably, the body is formed from an integral block defining the two chambers, the two chambers being in communication with one another through an intermediate passage, the second of the chambers which receives the filter communicating directly, in its lower region, with the oil/air tank, the upper region of the second chamber being closed by means of a head or cover member, the member carrying the oil-removing filter in its lower region and the control units in its upper region.

Alternatively, the body is formed from two body portions fixedly connected together in an intermediate plane, a first of the body portions defining a first chamber for the rotor of the compressor unit and the second body portion defining a second chamber for the oil-removing filter, the two chambers being in communication with one another through an intermediate passage the second chamber communicating directly, in its lower region, with the oil/air tank, upper region of the second chamber being closed by means of a head or cover member, the member carrying the oil-removing filter in its lower region and the control units in its upper region.

Desirably, the first and second chambers in the body are disposed so that their axes extend substantially parallel to one another, the axes, in use being disposed substantially vertically so that the compressor unit, the oil-removing filter and the oil/air tank are correspondingly orientated.

Advantageously, the oil-removing filter is surrounded by a protective circular member which extends towards the lower region of the oil/air tank.

Further preferably, the accessory devices comprise a non-return valve, an air discharge valve, an oil recovery unit and filter and a control selector each device being in the form of a cartridge and all of which are mounted in the head or cover unit carrying the oil-removing filter.

One embodiment of an air compressor in accordance with the present invention will be further described, by way of example, with reference to the accompanying drawings, in which: Fig. 1 is a vertical elevation, partially in section, of an air compressor in accordance with the present invention, the sectional portion corresponding to a section taken along the line I-I of Fig. 2.

Fig. 2 is a horizontal cross-sectional view taken along the line Il-Il of Fig. 1, Fig. 3 shows a plan view of the head of the tank/oil-removing filter unit forming part of the compressor shown in Fig. 1, and Fig. 4 is a cross-sectional view taken along the line IV--IV in Fig. 3.

An air compressor in accordance with the present invention and as shown in the drawings comprises a compressor unit 1, an oil/air tank 2 and an oil-removing filter 3, all of which are arranged and assembled together by means of a loadbearing body 4.

The loadbearing body 4 comprises a first portion 5 acting as a stator or housing which defines a chamber 6 in which a bladed rotor 7 of the compressor unit 1 rotates in a known manner.

The rotor is driven by a motor 9 through the intermediary of a shaft 8. The motor 9 is fixed and supported by the portion 5 of the body 4, preferably in the lower region thereof.

The load-bearing body 4 has a second portion 1 5 which, in turn, defines a chamber 16 for the oil-removing filter 3 and which also acts as a support member for the oil/air tank 2. The tank 2 is mounted so as to be coaxial with chamber 1 6 and the filter 3.

The body 4 is advantageously formed as shown in the drawings, in such a manner the two portions 5 and 1 5 are integral with one another.

Alternatively the body 4 may be formed from separate bodies corresponding portions 5 and 1 5 which are manufactured separately and then interconnected by means of flanges or any other suitable connection devices.

Whichever way the body 4 is made the mechanical construction of the body itself is simplified, greater accuracy in the assembly of the various units can be achieved, the assembly of the apparatus is simplified and the apparatus can be produced economically. It has also been found that the compressor acts more efficiently and is quieter in operation as a result of the mutual arrangement of the units which the body 4 described hereinbefore permits.

The chambers 6 and 16 defined by portions 5 and 15 respectively of the body 4 communicates directly with one another through an intermediate passage 1 7. The chamber 1 6 communicates directly with the tank 2 and in turn the tank 2 communicates with the filter 3. As a result of this, there is no loss of head. As shown in Fig. 1, the axes of the chambers 6 and 1 6 are preferably at least substantially parallel to one another and are orientated in a vertical plane. By so doing, the compressor unit 1 on the one hand and the tank 2 and the oil-removing filter 3 on the other hand are associated with one another and correspondingly orientated.

The external wall of the body 4 is provided with fins for the effective dispersion of heat from the apparatus.

As can be seen in Fig. 2, the portion 5 of the body has, in addition to the chamber 6 for the bladed rotor 7, an inlet 10 for air which is to be compressed, a controllable valve 11 for opening and closing the inlet 10 and a device 12 for supplying and distributing oil for the lubrication of the rotor 7. Support members for cooling the compressed air are connected to the tank 2 which operate in a known manner and will not, therefore, be described further.

In the body 4, and as shown in Fig. 1, the oilremoving filter 3 is connected by means of a rod 1 8 to a member 1 9 acting as a cover therefor, the member 19 being fixedly mounted in the upper region of the portion 15. In turn, the tank 2 is fixed, by means of bolts 20, to the lower part of the portion 1 5. The tank 2 is penetrated by the lower portion of a tubular member 21 which is fixedly mounted in the chamber 1 6. The member 21 surrounds the oil-removing filter 3 and is provided to ensure that the filter is not impacted directly by lubricated compressed air issuing from the compressor unit through the intermediate passage 1 7.

The member 19, which carries the oil-removing filter 3 and is affixed to the portion 15 of the body 4 also has associated therewith various control units such as an oil recovery unit including a filter 22 which recovers and recirculates any oil which is deposited on the base of the filter 3, a nonreturn valve 23 which sets the minimum pressure for the utilisation of the air, a valve 24 for discharging the air to atmosphere, and a selector 25 having an electrically operated valve or control valve 26 associated therewith, all of which units operate in a known manner, conduits, not shown, terminating at the recovery unit, the valves and the selector are also fixed to the member 1 9.

Advantageously, each of these control components are provided in the form of a cartridge which is housed and secured in a corresponding recess formed in the member 19.

Accordingly, in addition to being easy to fit, they can be easily and rapidly removed, maintained and replaced without the need for removing any other unit or for disconnecting the conduits which remain fixed to the member 19.

Claims

1. A bladed rotary air compressor comprising a compressor unit means of lubricating the compressor unit, an oil/air tank an oil-removing filter and accessory devices for controlling the minimum operating pressure, the discharge of air to atmosphere, the recovery and recycling of oil retained on the base of the oil-removing filter and the overall operation of the compressor wherein a single load-bearing body is provided which comprises a first portion forming a stator or housing defining a chamber for the bladed rotor of the compressor unit and means for supporting a drive device for the compressor unit and a second portion defining a chamber for the oil-removing filter and the control components, the oilremoving filter and the oil/air tank being coaxial with one another but being disposed at different levels.

2. An air compressor as claimed in claim 1, in which the body is formed from an integral block defining the two chambers, the two chambers being in communication with one another through an intermediate passage, the second of the chambers which receives the filter, communicating directly, in its lower region, with the oil/air tank, the upper region of the second chamber being closed by means of a head or cover member, the member carrying the oil-removing filter in its lower region and the control units in its upper region.

3. An air compressor as claimed in claim 1, in which the body is formed from two body portions fixedly connected together in an intermediate plane, a first of the body portions defining a first chamber for the rotor of the compressor unit and the second body portion defining a second chamber for the oil-removing filter, the two chambers being in communication with one another through an intermediate passage, the second chamber communicating directly, in its lower region, with the oil/air tank, the upper region of the second chamber being closed by means of a head or cover member, the member carrying the oil-removing filter in its lower region and the control units in its upper region.

4. An air compressor as claimed in claim 1, 2 ar 3, in which the first and second chambers in the body are disposed so that their axes extent substantially parallel to one another, the axes, in use, being disposed substantially vertically so that the compressor unit, the oil-removing filter and the oil/air tank are correspondingly orientated.

5. An air compressor as claimed in claim 1, in which the oil-removing filter is surrounded by a protective circular member which extends-towards the lower region of the oil/air tank.

6. An air compressor as claimed in any one of claims 1 to 3, in which the accessory devices comprise a non-return valve, an air discharge valve, an oil recovery unit and filter and a control selector each device being in the form of a cartridge and all of which are mounted in the head or cover unit carrying the oil-removing filter.

7. An air compressor as claimed in claim 1 constructed and arranged to operate substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.