Patent Document

CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims priority to U.S. Provisional Application entitled, REFRIGERANT RECOVERY METHOD AND APPARATUS, filed Nov. 19, 2004, having a Ser. No. 60/629,314, the disclosure of which is hereby incorporated by reference in its entirety. 
    
    
     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. 
     There has thus been outlined, rather broadly, certain embodiments of the invention in order that the detailed description thereof herein may be better understood, and in order that the present contribution to the art may be better appreciated. There are, of course, additional embodiments of the invention that will be described below and which will form the subject matter of the claims appended hereto. 
     In this respect, before explaining at least one embodiment of the invention in detail, it is to be understood that the invention is not limited in its application to the details of construction and to the arrangements of the components set forth in the following description or illustrated in the drawings. The invention is capable of embodiments in addition to those described and of being practiced and carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein, as well as the abstract, are for the purpose of description and should not be regarded as limiting. 
     As such, those skilled in the art will appreciate that the conception upon which this disclosure is based may readily be utilized as a basis for the designing of other structures, methods and systems for carrying out the several purposes of the present invention. It is important, therefore, that the claims be regarded as including such equivalent constructions insofar as they do not depart from the spirit and scope of the present invention. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a functional block diagram according to a preferred embodiment of the invention. 
         FIG. 2  is a front view of the instrument panel according to the preferred embodiment of the present invention. 
         FIG. 3  is a schematic of the manifold according to the preferred embodiment of the present invention. 
         FIG. 4  illustrates the valve layout of the manifold according to the preferred embodiment of the present invention. 
         FIG. 5  is a flow diagram of the recovery mode according to the preferred embodiment of the present invention. 
         FIG. 6  is a flow diagram of the evacuation mode according to the preferred embodiment of the present invention. 
         FIG. 7  is a flow diagram of the recovery purge mode according to the preferred embodiment of the present invention. 
     
    
    
     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 in  FIG. 1 , which is a functional block diagram. The device  10  includes a motor  12 . Attached to the motor  12  are a vacuum  14  and a compressor  16 . The motor  12  is connected to the vacuum  14  through a vacuum shaft  18  and a vacuum clutch  20 . The motor  12  is also connected to the compressor  16  through a compressor shaft  22  and a compressor clutch  24 . As is depicted by  FIG. 1 , the vacuum  14  and the compressor  16  are located on opposing sides of the motor  12 . 
     The motor  12  is a reversible motor that can rotate in a bidirectional manner. For example, if the motor  12  rotates in one direction, the vacuum shaft  18  is rotated such that it engages the vacuum clutch  20 . While the vacuum shaft  18  is rotating in one direction, the compressor shaft  22  is rotating in the same directional as well. However, the compressor clutch  24  is not engaged and therefore the compressor  16  is not activated. The compressor shaft  22  essentially spins freely in this first direction due to the clutch  24 . 
     The motor  12  can rotate in a second direction in which the compressor shaft  22  engages the compressor clutch  24 . At the same time, the vacuum shaft  18  rotates in the second direction but does not engage the vacuum  14  because of the vacuum clutch  20 . The vacuum shaft  18  essentially spins freely in this second direction due to the clutch  22 . 
       FIG. 1  also depicts an output storage tank  24  that receives and stores the gas from a mechanical system. The device  10  draws the gas from the system and directs it to the output storage tank  24 . 
     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. 2  is a front view of the instrument panel  28  according to the preferred embodiment of the present invention. The instrument panel  28  illustrates a first gauge  30  and a second gauge  32  that aids a technician to monitor the recovery and evacuation system. The instrument panel  28  includes an actuator  34  that enables the technician to alternate between recovery and vacuum, which is the evacuate mode. The instrument panel further includes an input port  36  and an output port  38 . 
       FIG. 3  is an internal view of the instrument panel  28 . The figure details the internal valve structure for the present invention. The actuator  34  alters the flow path of the present invention based upon the mode selected. The actuator  34  accomplishes 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 actuator  34  is that it moves an electrical contact bar  40  into the appropriate position based upon the mode selected. For example, if the actuator is positioned in the vacuum mode, then the contact bar  40  is positioned in contact with the vacuum electrical connection  42 . If the recovery mode is selected, the contact bar  40  is positioned such that it is in contact with the compressor electrical connection  44 . In either instance, the contact bar  40  is positioned through the gears of both the actuator  34  and the contact bar  40 . 
     Once the contact bar  40  is contact with one of the electrical connections  42 ,  44 , power is then able to be supplied to the requisite device. For example, if the actuator  34  is in the vacuum mode, then an electrical connection is made with the contact bar  40  such that the power is able to be supplied to the vacuum pump  14 . If the actuator  34  is in the compressor mode, then an electrical connection is made with the contact bar  40  such that the power is able to be supplied to the compressor  16 . 
       FIG. 4  is 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 actuator  34  in which a valve  46 , such as a ball valve, is moved from a first position to a second position.  FIG. 4  illustrates the valve  46  in 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 actuator  34  is in the recovery mode. 
       FIG. 5  is a flow diagram of the recovery mode according to the preferred embodiment of the present invention. At the inlet port  48 , the gas in drawn into the system, pass the actuator  34  and then on to the compressor  48 . Positioned between the compressor and the actuator  34  is a pressure gage  50  in order to monitor the recovery suction. Additionally, there is a low pressure switch  51  positioned between the gage  50  and the compressor  48 . 
     The low pressure switch  51 , in the preferred embodiment, is included in the present invention because the compressor  48  is 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 switch  51  is activated and the compressor is disconnected. The low pressure switch  51  prevents the compressor from being operated in an oil-less environment. 
     The output of the compressor  48  is then passed through a condenser  50  and then delivered to the output port  38 . In between the compressor  48  and the condenser  50  are a first high pressure switch  52  and a second high pressure switch  54 . 
       FIG. 6  is a flow diagram of the evacuation mode according to the preferred embodiment of the present invention. In this figure, the actuator  34  is set to vacuum or evacuation mode. The flow path is altered such that the fluid or gas flows through the input port  36  and passed directly to the vacuum pump  52 , which then exhausts the fluid to the atmosphere. 
     The vacuum pump  52  has a high pressure switch  54  that is mounted at the vacuum input port  56 . In the preferred embodiment, the high pressure switch  54  is set at five pounds per square inch (PSI). This switch  54  does not allow the motor  12  to engage vacuum pump  52  if there is pressure at the inlet port  56 . 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 pump  52  from operating. If pressure is allowed to enter to the vacuum pump  52 , then the vacuum pump  52  is likely to be damaged. 
       FIG. 7  is a flow diagram of the recovery purge mode according to the preferred embodiment of the present invention. In this mode, the actuator  34  is closed such that no more gas or fluid is permitted to enter the present invention either to the compressor  48  or the vacuum pump  52 . 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 port  38  and on to the storage tank  26 . 
     The many features and advantages of the invention are apparent from the detailed specification, and thus, it is intended by the appended claims to cover all such features and advantages of the invention which fall within the true spirit and scope of the invention. Further, since numerous modifications and variations will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation illustrated and described, and accordingly, all suitable modifications and equivalents may be resorted to, falling within the scope of the invention.

Technology Category: f