Refrigerant recovery apparatus with variable vacuum time and method

A mobile air conditioning (AC) recovery system, comprising:

• a compressor to evacuate a refrigerant from a vehicle AC system during a first phase and a second phase of a refrigerant recovery process;
• a vacuum pump to evacuate the refrigerant from the vehicle AC system during the second phase of the refrigerant recovery process;
• a memory to store one or more correlation relations to determine a variable second recovery time for the second phase of the refrigerant recovery process to evacuate the refrigerant from the vehicle AC system to a second predetermined level related to a first recovery time to evacuate the refrigerant from the vehicle AC system to a first predetermined level during the first phase of the refrigerant recovery process;
• and a processor to selectively control the compressor and the vacuum pump to evacuate the refrigerant from the vehicle AC system to the first and second predetermined levels, wherein:
• the processor controls the compressor to operate to evacuate the refrigerant from the vehicle AC system to the first predetermined level during the first phase of the refrigerant recovery process and determines the first recovery time to evacuate the refrigerant from the vehicle AC system to the first predetermined level, the processor determines the variable second recovery time for the second phase of the recovery process to evacuate the refrigerant from the vehicle AC system from the first predetermined level to the second predetermined level by applying in the one or more correlation relations the first recovery time to evacuate the refrigerant from the vehicle AC system to the first predetermined level, and the processor controls the compressor to operate together with the vacuum pump for the variable second recovery time to evacuate the refrigerant from the vehicle AC system to the second predetermined level during the second phase of the refrigerant recovery process.

A recovery system, comprising:

• a first means for evacuating a gas or liquid from a vessel or system during a first phase and a second phase of a recovery process;
• a second means for evacuating the gas or liquid from the vessel or system during the second phase of the recovery process;
• and
• a control means for selectively controlling the first means and the second means for evacuating the gas or liquid from the vessel or system, wherein:
• the control means controls the first means for evacuating to evacuate the vessel or system to a first predetermined level during the first phase of the recovery process and determines a first recovery time to evacuate the vessel or system to the first predetermined level,
• the control means determines a variable second recovery time for the second phase of the recovery process to evacuate the vessel or system from the first predetermined level to a second predetermined level by applying in one or more correlation relations the first recovery time to evacuate the vessel or system to the first predetermined level, and
• the control means controls the first means for evacuating to operate together with the second means for evacuating for the variable recovery second time to evacuate the vessel or system to the second predetermined level during the second phase of the recovery process.

A recovery method, comprising:

• monitoring the evacuation of gas or liquid from a vessel or system with a processor during a first phase of a recovery process to a first predetermined level;
• using the processor to determine a first recovery time to evacuate the vessel or system to the first predetermined level during the first phase of the recovery process;
• using the processor to determine a variable second recovery time for a second phase of the recovery process to evacuate the vessel or system from the first predetermined level to a second predetermined level by applying in one or more correlation relations the first recovery time to evacuate the vessel or system to the first predetermined level;
• using the processor to control the evacuation of the gas or liquid from the vessel or system for the variable second recovery time during the second phase of the recovery process to evacuate the gas or liquid from the vessel or system to the second predetermined level;
• using the processor to control the evacuation of the gas or liquid from the vessel or system to the first predetermined level by operation of a compressor during the first phase of the recovery process;
• and using the processor to control the evacuation of the gas or liquid from the vessel or system to the second predetermined level by operation of the compressor together with a vacuum pump for the variable recovery time during the second phase of the recovery process.

A tangible computer readable medium having embodied thereon computer-executable instructions for execution of a gas or liquid recovery method by a processor, the method comprising:

• evacuating gas or liquid from a vessel or system during a first phase of a recovery process to a first predetermined level;
• determining a first recovery time to evacuate the vessel or system to the first predetermined level during the first phase of the recovery process;
• determining a variable second recovery time for a second phase of the recovery process to evacuate the vessel or system from the first predetermined level to a second predetermined level by applying in one or more correlation relations the first recovery time to evacuate the vessel or system to the first predetermined level;
• evacuating the gas or liquid from the vessel or system for the variable second recovery time during the second phase of the recovery process to evacuate the gas or liquid from the vessel or system to the second predetermined level;
• evacuating the gas or liquid from the vessel or system to the first predetermined level by operation of a compressor during the first phase of the recovery process;
• and evacuating the gas or liquid from the vessel or system to the second predetermined level by operation of the compressor together with a vacuum pump for the variable recovery time during the second phase of the recovery process.