Compressor low cost oil filter

1. A transport refrigeration system (TRS) compressor, the compressor comprising:

a crankcase;

a crankshaft;

an oil filter including a filter media, the crankshaft and the oil filter disposed within the crankcase;

an oil pump configured to pump oil to the crankshaft and the oil filter;

an oil sump configured store oil received from the crankshaft and the oil filter; and

a pressure regulator in fluid communication with the oil pump and the oil filter, the pressure regulator configured to regulate an oil pressure of oil directed from the oil pump to the oil filter,

wherein the oil filter is disposed downstream of the pressure regulator and the oil sump is disposed downstream of the oil filter so that a first portion of oil flows from the oil pump to the pressure regulator, then to the oil filter, and then to the oil sump, and

wherein the oil filter is an inside-out filter that is absent of a housing, the oil filter includes a filter media, and oil received from the pressure regulator penetrates through the filter media and flows into the oil sump from an outside surface of the filter media.

2. The TRS compressor of claim 1 , wherein the TRS compressor is configured to achieve between about 10 to about 50 cubic inches of displacement per revolution.

3. The TRS compressor of claim 1 , wherein the TRS compressor is configured to achieve about 30 cubic inches of displacement per revolution.

4. The TRS compressor of claim 1 , wherein the oil filter includes a bypass valve having an open state and a closed state and being configured to, in the open state, allow oil from the oil pump that enters the oil filter to bypass filtration through the filter media and to exit the oil filter to the oil sump.

5. The TRS compressor of claim 4 , wherein the bypass valve is a pressure relief device and is configured to be in the open state when a pressure differential in the oil filter is greater than a predetermined pressure differential value and is configured to be in the closed state when the pressure differential in the oil filter is less than or equal to the predetermined pressure differential value.

6. The TRS compressor of claim 5 , wherein the predetermined pressure differential value is a value set between about 5 to about 10 psid.

7. The TRS compressor of claim 1 , further comprising an oil pickup tube in fluid communication with the oil pump and the oil filter, the oil pickup tube configured to direct oil from the oil pump to the oil filter,

the oil filter including a mounting bracket, and

wherein the oil filter is attached to the oil pickup tube via the mounting bracket.

8. The TRS compressor of claim 1 , wherein a portion of the oil filter is disposed in the oil sump.

9. An oil filter disposed in a compressor of a transport refrigeration system, the oil filter comprising:

a filter media defining an inner space;

an upper endcap attached to a top surface of the filter media, the upper end cap including an upper opening that is in fluid communication with the inner space;

a bottom endcap attached to a bottom surface of the filter media that is opposite the top surface, the bottom endcap including a bottom opening that is in fluid communication with the inner space; and

a mounting bracket attached to the bottom surface of the bottom endcap, the mounting bracket configured to attach to the compressor.

10. The TRS compressor of claim 1 , further comprising an oil pickup tube and an oil returning tube, wherein the filter media defines an inner space, and the oil filter further comprises

an upper endcap attached to a top surface of the filter media, the upper end cap including an upper opening that is in fluid communication with the inner space;

a bottom endcap attached to a bottom surface of the filter media that is opposite the top surface, the bottom endcap including a bottom opening that is in fluid communication with the inner space; and

a mounting bracket attached to the bottom surface of the bottom endcap, the mounting bracket configured to attach to the compressor,

wherein the oil filter is attached to the oil pickup tube via the mounting bracket;

the oil pickup tube is configured to direct oil from the oil pump to the pressure regulator, the oil pickup tube is in fluid communication with the oil pump and the pressure regulator;

the oil returning tube is connected to an outlet of the pressure regulator and is inserted inside the inner space through the upper opening so that oil from the pressure regulator is directed to the oil filter via the oil returning tube;

the oil filter includes a bypass valve having an open state and a closed state and being configured to, in the open state, allow oil from the oil pump that enters the oil filter to bypass filtration through the filter media and to exit the oil filter to the oil sump;

the bypass valve is positioned in the oil sump, the bypass valve is attached to the bottom endcap, and the bypass valve is configured to be in fluid communication with the inner space;

the bypass valve includes a bypass valve retainer that houses a bypass valve spring and a bypass valve flat plate, wherein when a pressure differential in the oil filter is greater than a predetermined pressure differential value, the bypass valve flat plate is pushed by the pressure differential toward the bypass valve spring, and the bypass valve is in the open state; when the pressure differential in the oil filter is less than or equal to the predetermined pressure differential value, the bypass valve flat plate is biased by the bypass valve spring to block the bottom opening, and the bypass valve is in the close state;

the bypass valve is positioned downstream of the oil filter so that oil from the oil pump enters the oil filter before reaching the bypass valve; and

the mounting bracket is radially spaced from the bypass valve.