Refrigerant recovery method and apparatus

A method and apparatus for recovering fluids in various states from a system includes a motor that is configured to engage a compressor in a first direction and engage a compressor in a second direction depending on the fluids contained therein.

FIELD OF THE INVENTION

The present invention relates generally to recovery of fluids in varying states. More particularly, the present invention relates to a single device that is capable of recovering gases such as refrigerant in both a liquid and gas state.

BACKGROUND OF THE INVENTION

Gases such as refrigerants are used in a variety of applications for a variety of uses. Refrigerant gases are used in refrigerators and air conditioning units in order to achieve lower ambient temperatures. For example, refrigerant gas is used in air conditioning systems in order to achieve lower temperatures. Additionally, the refrigerant gases are used in storages device such as refrigerators and freezers. The gases are used to lower the temperature inside these devices in order to protect items stored therein.

These gases are stored in a closed loop system in order to prevent them from leaking. If the gases were to leak, then the systems are limited by their ability to lower the temperature.

The mechanical systems, in which the gases are stored, are subject to failure and breakdown and therefore require maintenance. When repairing these systems due to leaks or other problems, these closed systems must be opened. Unbeknownst to many, the opening of these systems allows the gases to escape and in some instances cause environmental damage.

Various governmental entities have taken action in response to this damage and have enacted laws to ensure that these gases are not allowed to escape into the atmosphere. These laws or regulations require that the refrigerant be removed from the system and stored in another closed system.

An inherent problem with the regulations is that the various portions of refrigerant can be in different states in the system. Therefore, one system is needed to remove liquid refrigerant and another system is needed to remove any gas refrigerant and other impurities. By having two separate systems, the cost is exponential greater to the technician. Additionally, by having two separate systems, the technician would need to bring two fairly heavy systems with him to the location of the closed system. This is particularly difficult for commercially refrigerant systems that are located on rooftops.

Accordingly, it is desirable to provide a method and apparatus that enables a technician to use one device in order to recovery varying states of a gas and impurities from a system. It is further desirable to provide a device that is easily transportable from location to location.

SUMMARY OF THE INVENTION

The foregoing needs are met, to a great extent, by the present invention, wherein in one aspect an apparatus is provided that in some embodiments includes a bidirectional motor to which a compressor is attached to one side of the motor and a vacuum pump is attached to the other side. By combining a motor into the apparatus that simultaneously attaches to a compressor and apparatus, a mechanical system is able to be purged of all gases and fluids with a single tool.

In accordance with one embodiment of the present invention, a recovery apparatus includes a motor, a compressor linked to one side of the motor and a vacuum pump linked to the other side of the motor. The recovery apparatus is configured such that when the motor rotates in one direction it engages the compressor and when it rotates in a second direction, the motor engages the compressor.

DETAILED DESCRIPTION

The invention will now be described with reference to the drawing figures, in which like reference numerals refer to like parts throughout. An embodiment in accordance with the present invention provides a single device that permits both recovery and evacuation of gases from a mechanical system. The embodiment further permits a single motor to be used to run both a vacuum and a compressor in order to achieve the evacuation and recovery of the gases.

An embodiment of the present inventive apparatus and method is illustrated inFIG. 1, which is a functional block diagram. The device10includes a motor12. Attached to the motor12are a vacuum14and a compressor16. The motor12is connected to the vacuum14through a vacuum shaft18and a vacuum clutch20. The motor12is also connected to the compressor16through a compressor shaft22and a compressor clutch24. As is depicted byFIG. 1, the vacuum14and the compressor16are located on opposing sides of the motor12.

The motor12is a reversible motor that can rotate in a bidirectional manner. For example, if the motor12rotates in one direction, the vacuum shaft18is rotated such that it engages the vacuum clutch20. While the vacuum shaft18is rotating in one direction, the compressor shaft22is rotating in the same directional as well. However, the compressor clutch24is not engaged and therefore the compressor16is not activated. The compressor shaft22essentially spins freely in this first direction due to the clutch24.

The motor12can rotate in a second direction in which the compressor shaft22engages the compressor clutch24. At the same time, the vacuum shaft18rotates in the second direction but does not engage the vacuum14because of the vacuum clutch20. The vacuum shaft18essentially spins freely in this second direction due to the clutch22.

FIG. 1also depicts an output storage tank24that receives and stores the gas from a mechanical system. The device10draws the gas from the system and directs it to the output storage tank24.

The clutches, in the present invention, are known as drawn cup roller clutches. These clutches transmit torques between the shaft and housing in one direction and allow free overrun in the opposite direction. When transmitting torque, either the shaft or the housing can be the input member.

These clutches operate in two modes, the overrun mode and the lock mode. The operation mode is controlled by the direction of the clutch or shaft rotation with respect to the locking ramps located in the clutch. In the overrun mode, the relative rotation between the housed clutch and the shaft causes the rollers to move away from the locking position against the locking ramps in the drawn cup. The housing and the clutch are thus free to overrun in one direction, or the shaft is free to overrun in the other direction.

In the lock mode, the relative rotation between the housed clutch and the shaft is opposite to that in the overrun mode. The rollers, assisted by the leaf type springs, become wedged between the locking ramps and the shaft as well is opposite to that in the overrun mode. The rollers, assisted by the leaf type springs, become wedged between the locking ramps and the shaft to transmit torque between two members. Either the member housing the clutch drives the shaft in one direction, or the shaft can drive the clutch and its housing member in the other direction. The present invention uses a Torrington drawn cup roller clutch, which is manufactured by the The Torrington Company, in Torrington, Conn.

FIG. 2is a front view of the instrument panel28according to the preferred embodiment of the present invention. The instrument panel28illustrates a first gauge30and a second gauge32that aids a technician to monitor the recovery and evacuation system. The instrument panel28includes an actuator34that enables the technician to alternate between recovery and vacuum, which is the evacuate mode. The instrument panel further includes an input port36and an output port38.

FIG. 3is an internal view of the instrument panel28. The figure details the internal valve structure for the present invention. The actuator34alters the flow path of the present invention based upon the mode selected. The actuator34accomplishes two goals. The first goal is to alter the flow path based on the mode of the system selected. Therefore, if the recovery mode is selected, then the flow path is in a first direction. If the evacuate mode is selected, then the flow path in changed or altered to a second direction.

The second goal of the actuator34is that it moves an electrical contact bar40into the appropriate position based upon the mode selected. For example, if the actuator is positioned in the vacuum mode, then the contact bar40is positioned in contact with the vacuum electrical connection42. If the recovery mode is selected, the contact bar40is positioned such that it is in contact with the compressor electrical connection44. In either instance, the contact bar40is positioned through the gears of both the actuator34and the contact bar40.

Once the contact bar40is contact with one of the electrical connections42,44, power is then able to be supplied to the requisite device. For example, if the actuator34is in the vacuum mode, then an electrical connection is made with the contact bar40such that the power is able to be supplied to the vacuum pump14. If the actuator34is in the compressor mode, then an electrical connection is made with the contact bar40such that the power is able to be supplied to the compressor16.

FIG. 4is a front view diagram of the valve portion of the present invention. This figure, illustrates in greater detail, the valve path assembly. Specifically, this figure depicts the internal chamber of the actuator34in which a valve46, such as a ball valve, is moved from a first position to a second position.FIG. 4illustrates the valve46in an open position such that the gases received at the input port are permitted to travel through the flow paths. In this open position, the actuator34is in the recovery mode.

FIG. 5is a flow diagram of the recovery mode according to the preferred embodiment of the present invention. At the inlet port48, the gas in drawn into the system, pass the actuator34and then on to the compressor48. Positioned between the compressor and the actuator34is a pressure gage50in order to monitor the recovery suction. Additionally, there is a low pressure switch51positioned between the gage50and the compressor48.

The low pressure switch51, in the preferred embodiment, is included in the present invention because the compressor48is an oil-less compressor. The compressor relies on the oil in the refrigerant for lubrication for such things as the piston seals.

When the present invention is in the recovery mode, there needs to be a minimum amount of pressure in the system especially for the oil-less compressor which requires lubrication in order to operate. If there is not a minimum amount of pressure, then low pressure switch51is activated and the compressor is disconnected. The low pressure switch51prevents the compressor from being operated in an oil-less environment.

The output of the compressor48is then passed through a condenser50and then delivered to the output port38. In between the compressor48and the condenser50are a first high pressure switch52and a second high pressure switch54.

FIG. 6is a flow diagram of the evacuation mode according to the preferred embodiment of the present invention. In this figure, the actuator34is set to vacuum or evacuation mode. The flow path is altered such that the fluid or gas flows through the input port36and passed directly to the vacuum pump52, which then exhausts the fluid to the atmosphere.

The vacuum pump52has a high pressure switch54that is mounted at the vacuum input port56. In the preferred embodiment, the high pressure switch54is set at five pounds per square inch (PSI). This switch54does not allow the motor12to engage vacuum pump52if there is pressure at the inlet port56. Pressure can be detected in evacuate mode for such things as incorrect connections. If there is pressure, then the electrical circuit to the motor is opened. The open circuit prevents the vacuum pump52from operating. If pressure is allowed to enter to the vacuum pump52, then the vacuum pump52is likely to be damaged.

FIG. 7is a flow diagram of the recovery purge mode according to the preferred embodiment of the present invention. In this mode, the actuator34is closed such that no more gas or fluid is permitted to enter the present invention either to the compressor48or the vacuum pump52. As the directional arrows indicate, the flow path for the recovery mode is completely closed such that any gas or liquid remaining in the system is cleaned out and passed on to the outlet port38and on to the storage tank26.