Refrigerant control valve with an enhanced flow modulating plug configuration
An example refrigerant control valve includes: a modulating plug that is linearly movable to control refrigerant flow rate from a first port to a second port; a first chamber formed at a first side of the modulating plug and fluidly coupled to the first port; a second chamber formed at a second side of the modulating plug, opposite the first side; a first flow restriction that fluidly couples the first chamber to the second chamber, and a second flow restriction that fluidly couples the second chamber to the second port.
1 . A refrigerant control valve comprising:
a modulating plug that is linearly movable to control refrigerant flow rate from a first port to a second port;
a first chamber formed at a first side of the modulating plug, wherein the first chamber is fluidly coupled to the first port;
a second chamber formed at a second side of the modulating plug, opposite the first side;
a first flow restriction that fluidly couples the first chamber to the second chamber; and
a second flow restriction that fluidly couples the second chamber to the second port, wherein refrigerant received at the first port flows to the first chamber, then through the first flow restriction to the second chamber, then through the second flow restriction to the second port, thereby creating an intermediate pressure level in the second chamber, which is lower than inlet pressure level at the first port and higher than outlet pressure level at the second port such that a net fluid force is applied to the modulating plug due to pressure applied by refrigerant in the first chamber and refrigerant in the second chamber, wherein the intermediate pressure level and the net fluid force are based on respective sizes of the first flow restriction and the second flow restriction.
2 . The refrigerant control valve of claim 1 , wherein the first flow restriction includes one or more vent holes formed in the modulating plug, wherein refrigerant received at the first port flows to the first chamber, then through the one or more vent holes to the second chamber, thereby causing pressure to decrease from the first port to the second chamber.
3 . The refrigerant control valve of claim 2 , further comprising:
a restrictor plate; and
one or more pins emanating from the restrictor plate toward the one or more vent holes to be inserted therethrough, such that an annular flow area is formed between each of the one or more pins and a respective vent hole of the one or more vent holes, wherein as the modulating plug moves linearly, a respective size of the annular flow area and the first flow restriction varies, thereby varying the intermediate pressure level in the second chamber and the net fluid force applied to the modulating plug.
4 . The refrigerant control valve of claim 3 , wherein the one or more pins are tapered pins.
5 . The refrigerant control valve of claim 2 , further comprising:
one or more spring-loaded pins inserted through the one or more vent holes respectively and retained to the modulating plug, wherein a flow area is formed between each of the one or more spring-loaded pins and a respective vent hole of the one or more vent holes, wherein as the modulating plug moves linearly, a respective size of the flow area and the first flow restriction varies, thereby varying the intermediate pressure level in the second chamber and the net fluid force applied to the modulating plug.
6 . The refrigerant control valve of claim 5 , wherein each of the spring-loaded pins is biased by a spring having a first end resting against the modulating plug and a second end resting against a flange formed in a respective spring-loaded pin.
7 . The refrigerant control valve of claim 5 , wherein each of the spring-loaded pins includes a groove having a variable depth along a length of a respective spring-loaded pin, thereby causing the respective size of the flow area and the first flow restriction to vary as the modulating plug moves linearly.
8 . The refrigerant control valve of claim 1 , wherein the second flow restriction includes one or more vent channels formed in the modulating plug.
9 . The refrigerant control valve of claim 8 , wherein the second flow restriction further includes one or more orifices that fluidly couple the one or more vent channels to the second port.
10 . The refrigerant control valve of claim 9 , wherein the one or more orifices are formed in the modulating plug.
11 . The refrigerant control valve of claim 8 , further comprising:
one or more vent tubes respectively inserted into the one or more vent channels.
12 . The refrigerant control valve of claim 11 , further comprising:
a manifold ring coupled to the one or more vent tubes.
13 . The refrigerant control valve of claim 12 , wherein the second flow restriction further includes one or more orifices that fluidly couple the one or more vent channels to the second port, and wherein the one or more orifices are formed in the manifold ring.
14 . The refrigerant control valve of claim 1 , wherein the first flow restriction is formed, at least partially, in the modulating plug.
15 . The refrigerant control valve of claim 1 , wherein the second flow restriction is formed, at least partially, in the modulating plug.
16 . The refrigerant control valve of claim 1 , further comprising:
a valve body; and
a plate coupled to the valve body such that the valve body and the plate form a cavity in which the modulating plug is movable.
17 . The refrigerant control valve of claim 16 , further comprising:
an inner housing disposed within the valve body and coupled to the plate such that the inner housing and the plate define the cavity in which the modulating plug is movable.
18 . The refrigerant control valve of claim 17 , wherein the inner housing includes one or more flow openings that allow refrigerant flow to the second port, wherein the one or more flow openings are disposed in an asymmetric configuration such that the one or more flow openings face the second port only.
19 . A method comprising:
receiving fluid at a first port of a refrigerant control valve, wherein the refrigerant control valve includes (i) a modulating plug that is linearly movable to control refrigerant flow rate from the first port to a second port, (ii) a first chamber formed at a first side of the modulating plug and fluidly coupled to the first port, and (iii) a second chamber formed at a second side of the modulating plug, opposite the first side;
flowing fluid from the first chamber through a first flow restriction to the second chamber, thereby causing pressure level in the second chamber to be lower than pressure level in the first chamber;
flowing fluid from the second chamber through a second flow restriction to the second port, thereby causing the pressure level in the second chamber to be higher than pressure level at the second port; and
applying a net fluid force to the modulating plug resulting from pressure applied by refrigerant in the first chamber and refrigerant in the second chamber, wherein the pressure level in the second chamber and the net fluid force are based on respective sizes of the first flow restriction and the second flow restriction.
20 . The method of claim 19 , further comprising:
varying a respective size of the first flow restriction as the modulating plug moves, thereby changing the net fluid force applied to the modulating plug.