ITMI20100097U1 - MACHINE FOR RECOVERY AND RECHARGE OF REFRIGERANT FLUID, PARTICULARLY FOR AERONAUTICAL USE. - Google Patents

Description

DESCRIPTION

The present invention relates to a machine for recovering and recharging refrigerant fluid, particularly for aeronautical use.

At present, machines are known which are capable of carrying out both the so-called "recharging" operation, i.e. the introduction of refrigerant fluid into a cooling system, and the so-called "recovery" operation, i.e. the removal of fluid. refrigerant, in any state, from the cooling system and collection inside a container.

Furthermore, known machines also carry out the so-called "emptying" operation, ie the removal of non-condensable gases and humidity from the cooling system by means of a high vacuum pump.

In the cooling systems on board the aircraft, there is a need to use a refrigerant fluid that is of high purity, free of polluting particles, as indicated by the NAS1638 standards, and absolutely free of oil or contaminants.

Known machines have the drawback of not offering adequate guarantees as regards full compliance with these standards, since it cannot be safely excluded that, during their operation, solid particles and oily contaminants may enter the cooling system.

The aim of the present invention is to provide a machine for recovering and recharging refrigerant fluid, particularly for aeronautical use, capable of overcoming the aforementioned drawback.

Within this aim, an object of the invention is to provide a machine which works even at low temperatures.

A further object of the invention is to provide a machine capable of operating on any type of refrigerant fluid, such as CFC (Chlorofluorocarbons, which are marketed under the name of 'freon'), HCFC (hydrochlorofluorocarbons) and 1 ' HFC (hydrofluorocarbons).

Another object of the invention is to provide a machine which allows the recovery of refrigerant fluid, as well as the complete emptying and subsequent recharging of a cooling system, by means of a solution which can be implemented in a simple way and with contained costs.

This task, as well as these and other purposes which will become clearer hereinafter, are achieved by a machine for the recovery and recharging of refrigerant fluid, particularly for aeronautical use, comprising means for connecting with the external environment associated with a connected main line, by means of a recharging line and by means of a recovery line, with a container suitable for containing a refrigerant fluid; on said recovery line being provided a first filter and a still for the separation from the contaminants and solid particles present in said refrigerant fluid; characterized in that it comprises on said recovery line a dry compressor defining a suction portion for sucking said refrigerant fluid from said main line and a delivery portion for sending said refrigerant fluid inside said container.

Further characteristics and advantages will become clearer from the detailed description of a machine for recovering and recharging refrigerant fluid, particularly for aeronautical use, according to the invention, illustrated, by way of non-limiting example, in the accompanying drawings, in which:

Figure 1 illustrates the hydraulic diagram of the machine, according to the invention, for the recovery and recharging of refrigerant fluid, particularly for aeronautical use;

Figure 2 illustrates the hydraulic diagram of the machine according to the invention during the operating step of recovering the refrigerant fluid from a cooling system;

Figure 3 illustrates the hydraulic diagram of the machine according to the invention during the operating step of recovering the refrigerant fluid from an external cylinder;

Figure 4 illustrates the hydraulic diagram of the machine according to the invention during the operating step of emptying a cooling system;

Figure 5 illustrates the hydraulic diagram of the machine according to the invention during the operating step of recharging the refrigerant fluid in a cooling system;

Figure 6 is a front view of a schematic arrangement of the individual components inside the machine, according to the invention, for the recovery and recharging of refrigerant fluid, particularly for aeronautical use;

Figure 7 is a side view of a schematic arrangement of the individual components inside the machine, according to the invention.

With reference to the aforementioned figures, the machine according to the invention, generally indicated by the reference number 1, comprises means for connecting 70 with the external environment, and in particular for coupling with an external cooling system 100 or with a cylinder service 101.

More specifically, these connecting means 70 comprise two couplings: a first coupling 71 for a low pressure line 72 of the machine 1 and a second coupling 73 for a high pressure line 74 of the machine 1.

More specifically, a first manually operated valve, 71a and 73a, is positioned in correspondence with each of the two couplings 71 and 73.

The pressure lines 72 and 74 are preferably defined by flexible pipes and on each of them there is a first pressure gauge, respectively 72a and 74a, and a second manually operated valve, respectively 72b and 74b.

The connecting means 70 with the external environment are associated, by means of the low pressure 72 and high pressure 74 lines, to a main line 75.

The main line 75 is connected by means of a recharging line 18 to a container 10 suitable for containing a refrigerant fluid and preferably in the shape of a cylinder.

More specifically, the container 10 has two connections: a first connection 11, equipped with a suction tube and provided for the cooling fluid in the liquid state and a second connection 12, without a suction tube and provided for the gaseous cooling fluid; both the first connection 11 and the second connection 12 are equipped with third manually operated valves, 11a and 12a respectively.

Conveniently, the container 10 is equipped with a safety valve 10a for discharging the non-condensable gases.

Advantageously, the container 10 comprises a thermostated resistance 13 and an electronic scale 14 for measuring the quantity of refrigerant fluid present in the container 10.

The main line 75 is connected to the container 10 by means of a refill line 18 and a recovery line 38 on which a distiller 30 and a first filter 40 are provided for the separation of the refrigerant fluid from the contaminants and solid particles present inside it. .

More specifically, the recharge line 18 comprises a passage line for the liquid-state refrigerant fluid 16, which is associated with the first connection 11 of the container 10 and is equipped with a humidity indicator 17.

A second filter 25 is positioned on the recharging line 18 to purify the liquid refrigerant fluid of the solid particles present inside it during the recharging phase, that is, as will be better described below, in the line that carries the refrigerant fluid from the container 10 towards the cooling circuit 100.

Advantageously, the second filter 25 can be positioned on the passage line for the liquid refrigerant 16.

The recharging line 18 is equipped with a first solenoid valve 18a and a first non-return valve 18b.

The recharging line 18 can also be associated with a service line 19 for recharging the refrigerant fluid, which is equipped at the inlet with a fourth manually operated valve 19a.

As previously mentioned, the recovery line 38 is equipped with the still 30 and the first filter 40.

According to the invention, a dry compressor 41, ie without lubricants, is provided on said recovery line 38, which divides said recovery line 38 into a suction portion 34 for suction of the refrigerant fluid present in the main line 75 and a delivery portion 42 for sending the refrigerant fluid inside the container 10.

By means of the suction portion 34, preferably defined by a flexible tube, the refrigerant fluid present in the main line 75, and coming from the cooling system 100 or inserted from the outside by means of a service cylinder 101, is sucked into the still 30.

More specifically, the suction portion 34 comprises a first portion 35 defined between the main line 75 and the still 30; a second section 36 defined between the still 30 and the first filter 40 and a third section 37 which goes from the first filter 40 to the dry compressor 41, which is equipped with a service connection 41a.

Conveniently, a pressure vacuum switch 35a, a second solenoid valve 35b and a second non-return valve 35c are provided on the first section 35 of the suction portion 34.

The delivery portion 42 on the other hand comprises two parts: a first part 43 which returns from the dry compressor 41 to the still 30 and a second part 44 which from the still 30 goes to the container 10.

More in detail, the still 30 comprises a distillation chamber 31 in which the separation of the refrigerant fluid from the oil and from the contaminating substances takes place. Furthermore, the still 30 comprises a heat exchange chamber between the exhaust gas and the recovered refrigerant fluid and a heat exchange coil between the exhaust gas and the recovered refrigerant fluid.

Preferably, the distiller 30 is of the type described in the patent MI91A003279.

Advantageously, the still 30 can be equipped with a device 60 for automatic flow control. This device 60 comprises a third solenoid valve 61 positioned on a capillary tube 62 interposed between the first section 35 of the suction portion 34 and the first part 43 of the delivery portion 42. The capillary tube 62 regulates the drop of water by means of the aforementioned third solenoid valve 61. pressure upstream and downstream of the dry compressor 41.

More specifically, the first filter 40 is of the dehydrating antacid type with an absorption capacity substantially equal to 40 grams of water. Furthermore, the first filter 40 can be of the cartridge type, having a filtering surface with a filtering capacity of substantially 2.5 micrometers.

Advantageously, a discharge line 39 exits from the distiller 30 and ends in a container 102 for collecting the contaminating oil which has been separated from the refrigerating fluid by distillation. The discharge line 39 has a fourth solenoid valve 39a and a third non-return valve 39b.

Therefore, with particular reference to Figures 2 and 3, the refrigerant fluid is sucked by the dry compressor 41 in the first section 35 of the suction portion 34 until it reaches the still 30. From here the refrigerant fluid is sucked into the second section 36 of the suction portion 34 until it reaches the first filter 40 where it undergoes a separation from the solid particles present therein. Through the third section 37 of the suction portion, the filtered refrigerant fluid passes beyond the dry compressor 41 to be sent to the first part 43 of the delivery portion 42, which brings it back into the still 30 where it undergoes distillation. Subsequently, through the second part 44 of the delivery portion 42, preferably defined by a flexible tube, the vapors of the refrigerant fluid which have been filtered from the solid components by means of the first filter 40 and separated from the oily contaminants by distillation, leave the distiller 30. Conveniently, a safety pressure switch 44a is provided on the second part 44 of the delivery portion 42.

Conveniently, the second part 44 of the delivery portion 42 comprises a condenser 45 which causes the cooling of the vapors of the refrigerant fluid, which are then introduced into the container 10 by crossing a line of passage of the refrigerant fluid in the gaseous state 15 connected to the second connection 12 of the container 10, the one arranged for the refrigerant fluid in the gaseous state.

A fourth non-return valve 15a and a fifth manually operated valve 15b for draining the container 10 are provided on the aforementioned line for the passage of the gaseous refrigerant fluid 15.

Advantageously, the main line 75 is further connected, by means of an emptying line 21, with a high vacuum pump 20 to suck and empty the cooling system 100, connected to the machine 1, from the residues of the technical gases used for pressing, from the atmospheric air and the steam that belongs to it and any water fractions formed through the condensation of the steam.

More particularly, the emptying line 21 comprises a vacuum switch 24 which adjusts the action of the high vacuum pump 20 so that the pressure value remains constant over time; a fifth solenoid valve 21a is also associated with the high vacuum pump 20.

Preferably, the high vacuum pump 20 is of the rotary vane type, lubricated by oil injection and has a flow rate substantially comprised between 250 l / min and 440 l / min.

Advantageously, a vacuum test line 22 equipped with a sixth solenoid valve 22a for regulating the pressure inside the line 22 is defined on the emptying line 21 of the high vacuum pump 20; moreover, a connection is provided to a second pressure gauge 23 to measure and provide an indication to the operator of the pressure value present in the vacuum test line 22.

Preferably, the recharging line 18, the main line 75, the recovery line 38 all meet in a common connection point 80 in which an indicator 81 is positioned to check the passage of the refrigerant fluid. The indicator 81 can be either electronic or a simple transparent glass through which the operator can visually check the passage of the refrigerant fluid.

Advantageously, the emptying line 21 is also connected to said common connection point 80.

Preferably, the machine 1 is entirely housed on a bearing structure 2 equipped with displacement means 2a.

More specifically, the supporting structure 2 comprises a substantially box-shaped base 3 at the bottom, designed for housing the dry compressor 41, the high vacuum pump 20 and the condenser 45. Furthermore, the supporting structure 2 comprises a wall 4, inside which the distiller 30 is housed, and which extends vertically from the upper face 5 of the aforementioned base 3. The bottom 6 of the base 3 is a quadrilateral equipped, at its angles with displacement means 2a, such as for example of the wheels.

The container 10 is positioned on the zone 7 of the upper face 5 not occupied by the wall 4 and preferably has a maximum capacity of ten kilograms and a weight, when empty, of eight kilograms. Furthermore, a shelf 8 is defined on one face of the wall 4 for supporting the container 102.

In correspondence with zone 7, next to the container 10 and interposed between two flexible pipes, there is the cartridge filter 40. The two flexible pipes between which the aforementioned first filter 40 is interposed are the second section 36 and the third section. section 37 of the intake portion 34.

The wall 4 ends with an inclined portion 9 on the outer face of which an interface 90 for the operator is defined.

More specifically, the interface 90 comprises an ignition switch 91, two controls 92 and 93 for operating the second manually operated valves 72b and 74b and two displays 94 and 95 for indicating the pressure values detected by the first ones respectively. 72a and 74a pressure gauges. Furthermore, the interface 90 comprises control buttons 96 for setting the recovery, recharging and emptying functions and an electronic display 97 for indicating the pressure values measured by the second pressure gauge 23, as well as the quantity of refrigerant fluid measured by the electronic scale 14. Furthermore, the indicator 81 for checking the passage of the refrigerant fluid is also arranged in the interface 90.

The use of the machine 1 according to the invention, as far as the various operating steps are concerned, is as follows.

In the operating step of recovering the refrigerant fluid from the cooling system 100, the couplings 71 and 73 are associated with the connections 103 and 104 of the cooling system 100, respectively for low pressure and for high pressure. Following the opening of the first manually operated valves 71a and 73a and of the second manually operated valves 72b and 74b, the fluid is sucked by the dry compressor 41 into the main line 75 and then into the recovery line 38. After having been filtered by means of the first filter 40, the dry compressor 41 sends the refrigerant fluid into the still 30, where it is separated from the oily contaminants by distillation. The refrigerant fluid in the gaseous state leaving the distiller 30 is then cooled by means of the condenser 45 and arrives inside the container 10.

With reference to Figure 3, the refrigerant fluid can also be recovered from a service cylinder 101 and, in this situation, only one of the two couplings 71 and 73 is connected to the connection 105 of the service cylinder 101. Operation of the machine 1, according to the invention, during the operating step of recovery from a service cylinder 101 is substantially identical to that described above for the step of recovery from the external cooling system 100.

With reference to Figure 4, during an operational phase of emptying the cooling system 100, the latter is connected to the machine 1 as described above for the recovery phase. In the emptying phase, the high vacuum pump 20 is activated, which sucks the residues of the technical gases used for pressing, the atmospheric air from the cooling system 100 into the main line 75 and then into the emptying line 21. and the steam that belongs to it and any water fractions formed through the condensation of the steam. By doing so, the cooling system 100 is completely emptied.

With reference to Figure 5, during a phase of recharging the refrigerant fluid inside the cooling system 100, only one of the two couplings 71 and 73 of the machine 1, preferably the first coupling 71, remains associated with the respective coupling 103 and 104 of the cooling system 100. By operating the cooling system 100, the refrigerant fluid present in the container 10 is sucked into the recharging line 18, passing through the second filter 25 positioned in the passage line for the liquid refrigerant fluid 16. From the recharging line 18 then goes up into the main line 75 to then pass, through the low pressure line 72 or the high pressure line 74, inside the cooling system 100.

In practice it has been found that the machine, according to the invention, for the recovery of refrigerant fluid, as well as for the emptying and recharging of cooling systems, particularly for aeronautical use, fully achieves the intended task in that the use of a compressor dry allows to avoid, during the recovery phase of the refrigerant fluid from the external cooling system or from the external cylinder, the introduction of oily contaminants and solid particles inside the refrigerant fluid that is deposited in the container.

Furthermore, the presence of a second filter in the line of the refrigerant fluid in the liquid state confluent in the recharge line, allows, during the recharging phase of the cooling system, a further filtering of the refrigerant fluid taken from the container and therefore a further separation from the solid particles and contaminants present in the refrigerant fluid.

It should be noted that the concept underlying the invention, although it has been described with particular reference for use in the aeronautical sector, can also be used for similar applications in which a high purity of the refrigerant fluid is required.

In practice, the materials employed, so long as they are compatible with the specific use, as well as the dimensions, may be any according to the requirements and the state of the art.

Claims (11)

R IV E N D ICA C IO N I 1.Machine for the recovery and recharging of refrigerant fluid, particularly for aeronautical use, comprising means of connection (70) with the external environment (100; 101) associated with a main line (75) connected by means of a recharging line (18) and by means of a recovery line (38), with a container (10) adapted to contain a refrigerant fluid; on said recovery line (38) a first filter (40) and a still (30) being provided for the separation of the contaminants and solid particles present in said refrigerant fluid; characterized in that it comprises on said recovery line (38) a dry compressor (41) defining a suction portion (34) for withdrawing said refrigerant fluid from said main line (75) and a delivery portion (42) to send said refrigerant fluid inside said container (10). 2. Machine according to one or more of the preceding claims, characterized in that it comprises a second filter (25) on said refill line (18). 3. Machine according to claim 1, characterized in that said main line (75) is connected by means of an emptying line (21) with a high vacuum pump (20). 4. Machine according to claim 1, characterized in that said suction portion (34) comprises a first portion (35) defined between said main line (75) and said distiller (30), a second portion (36) defined between said distiller (30) and said first filter (40), and a third section (37) between said first filter (40) and said dry compressor (41); said delivery portion (42) comprising a first part (43) comprised between said dry compressor (41) and said distiller (30) and a second part (44) comprised between said distiller (30) and said container (10). 5. Machine according to one or more of the preceding claims, characterized in that said container (10) comprises a first connection (11) arranged for said liquid refrigerant fluid and associated with a passage line for said liquid refrigerant fluid (16) and a second connection (12) arranged for said refrigerant fluid in the gaseous state and associated with a passage line for said refrigerant fluid in the gaseous state (15). 6. Machine according to one or more of the preceding claims, characterized in that said second filter (25) is arranged on said line for the passage of said liquid refrigerant fluid (16). 7. Machine according to one or more of the preceding claims, characterized in that it comprises on said second part (44) of said delivery portion (42) a condenser (45) for cooling the vapors of the distilled refrigerant fluid. 8. Machine, according to one or more of the preceding claims, characterized in that said main line (75), said refill line (18) and said recovery line (38) meet in a common connection point (80) in the which an indicator (81) of the passage of said refrigerant fluid is positioned. 9. Machine according to one or more of the preceding claims, characterized in that said emptying line (21) is connected to said common connection point (80). 10. Machine, (according to one or more of the preceding claims, characterized in that it is entirely mounted on a bearing structure (2) equipped with displacement means (2a). 11. Machine for recovering and recharging refrigerant fluid, particularly for aeronautical use, characterized in that it comprises one or more of the characteristics described and / or illustrated.