1. A refrigerant vapor compression system including a compression device disposed in a refrigerant circuit for compressing a refrigerant vapor from a suction pressure to a discharge pressure, a heat rejecting heat exchanger disposed in the refrigerant circuit downstream with respect to refrigerant flow of the compression device, and a heat accepting heat exchanger disposed in the refrigerant circuit downstream with respect to refrigerant flow of the heat rejecting heat exchanger and upstream with respect to refrigerant flow of the compression device, the refrigerant vapor compression system characterized by:
an economizer heat exchanger having a first pass and a second pass operatively associated in heat transfer relationship, the first pass disposed in the refrigerant circuit downstream with respect to refrigerant flow of the heat rejecting heat exchanger and upstream with respect to refrigerant flow of the heat accepting heat exchanger;
a primary expander disposed in the refrigerant circuit downstream with respect to refrigerant flow of the first pass of said economizer heat exchanger and upstream with respect to refrigerant flow of said heat accepting heat exchanger;
an evaporator bypass line providing a refrigerant flow path for passing a partially expanded portion of the refrigerant from the refrigerant circuit after having traversed the first pass of said economizer heat exchanger through the second pass of said economizer heat exchanger and into an intermediate pressure stage of said compression device;
an economizer bypass line for passing a portion of the refrigerant from the refrigerant circuit into said evaporator bypass line at a location downstream with respect to refrigerant flow of the second pass of said economizer heat exchanger; and
a restrictor type expansion device disposed in said economizer bypass line for expanding the refrigerant passing therethrough to a lower pressure to provide a liquid component of refrigerant flow.
2. A refrigerant vapor compression system as recited in claim 1 further characterized in that said refrigerant circuit operates at least in part in a transcritical cycle.
3. A refrigerant vapor compression system as recited in claim 1 further characterized in that said refrigerant circuit operates at least in part in a subcritical cycle.
4. A refrigerant vapor compression system as recited in claim 1 further characterized in that said restrictor type expansion device is selected from the set of a fixed orifice, a capillary tube, a thermostatic expansion valve or an electronic expansion valve.
5. A refrigerant vapor compression system as recited in claim 1 further characterized in that the refrigerant circulating through the refrigerant circuit of said refrigerant vapor compression system is carbon dioxide.
6. A refrigerant vapor compression system as recited in claim 1 further characterized in that said economizer bypass line extends in refrigerant flow communication from a point in the refrigerant circuit upstream with respect to refrigerant flow of the first pass of the economizer heat exchanger and downstream with respect to refrigerant flow of the heat rejecting heat exchanger to a point in said evaporator bypass line downstream of the second pass of the economizer heat exchanger.
7. A refrigerant vapor compression system as recited in claim 1 further characterized in that said economizer bypass line extends in refrigerant flow communication from a point in the refrigerant circuit downstream with respect to refrigerant flow of the first pass of the economizer heat exchanger and upstream with respect to refrigerant flow of said primary expander to a point in said evaporator bypass line downstream of the second pass of the economizer heat exchanger.
8. A refrigerant vapor compression system as recited in claim 1 further characterized in that said evaporator bypass line extends in refrigerant flow communication from an intermediate expansion stage of said primary expander through the second pass of said economizer heat exchanger and into an intermediate compression stage of said compression device.
9. A refrigerant vapor compression system as recited in claim 8 further characterized in that said economizer bypass line extends in refrigerant flow communication from a point in the refrigerant circuit upstream with respect to refrigerant flow of the second pass of the economizer heat exchanger and downstream with respect to refrigerant flow of said primary expander to a point in said evaporator bypass line downstream of the second pass of the economizer heat exchanger.
10. A refrigerant vapor compression system as recited in claim 1 further characterized in that;
said evaporator bypass line extends in refrigerant flow communication from a point in the refrigerant circuit upstream with respect to refrigerant flow of said primary expander and downstream with respect to refrigerant flow of the first pass of said economizer heat exchanger through the second pass of said economizer heat exchanger and into an intermediate compression stage of said compression device; and
a secondary expander disposed in said evaporator bypass line upstream with respect to refrigerant flow of the second pass of said economizer heat exchanger.
11. A refrigerant vapor compression system as recited in claim 10 further characterized in that said economizer bypass line extends in refrigerant flow communication from a point in the refrigerant circuit downstream with respect to refrigerant flow of the first pass of the economizer heat exchanger and upstream with respect to the refrigerant flow of both the primary expander and the secondary expander to a point in said evaporator bypass line downstream of the second pass of the economizer heat exchanger.
12. A refrigerant vapor compression system as recited in claim 10 further characterized in that said primary expander is operatively connected in the refrigerant circuit upstream with respect to refrigerant flow of said evaporator to expand a major portion of the refrigerant flow having traversed the first pass of the economizer heat exchanger, and said secondary expander is operatively connected in said evaporator bypass line upstream with respect to refrigerant flow of the second pass of said economizer heat exchanger to expand a minor portion of the refrigerant flow having traversed the first pass of the economizer heat exchanger.
13. A refrigerant vapor compression system as recited in claim 1 wherein said primary expander comprises a single expander having a first expansion process for expanding the refrigerant flow having traversed the first pass of the economizer heat exchanger to a pressure intermediate the discharge pressure and the suction pressure, and a second expansion process for expanding the refrigerant flow having traversed the first pass of the economizer heat exchanger to a pressure approximating the suction pressure, said evaporator bypass line communicating with said expander device to receive a flow of refrigerant at the intermediate pressure.
14. A refrigerant vapor compression system as recited in claim 1 wherein said compression device comprises a first compressor and a second compressor, the first compressor having a discharge outlet connected in refrigerant flow communication to a suction inlet of the second compressor by a refrigerant line, said evaporator bypass line communicating with said refrigerant line at location between the discharge outlet of the first compressor and the suction inlet of the second compressor.
15. A refrigerant vapor compression system as recited in claim 1 wherein the compression device comprises a single compressor having compression chambers, said evaporator bypass line communicating with the compression chambers at an intermediate compression stage.
16. A refrigerant vapor compression system as recited in claim 1 further characterized in that a refrigerant flow control device is disposed in said evaporator bypass line.
17. A method of controlling refrigerant discharge temperature from a compression device in a refrigerant vapor compression system including a compression device disposed in a refrigerant circuit for compressing a refrigerant vapor from a suction pressure to a discharge pressure, a heat rejecting heat exchanger disposed in the refrigerant circuit downstream with respect to refrigerant flow of the compression device, a heat accepting heat exchanger disposed in the refrigerant circuit downstream with respect to refrigerant flow of the heat rejecting heat exchanger and upstream with respect to refrigerant flow of the compression device, and an economizer heat exchanger having a first pass and a second pass disposed in heat exchange relationship, the first pass disposed in the refrigerant circuit upstream with respect to refrigerant flow of the heat accepting heat exchanger and downstream with respect to refrigerant flow of the heat rejecting heat exchanger, the method comprising the steps of:
passing a major portion of the refrigerant having traversed the first pass of said economizer heat exchanger through an expander to fully expand to a first pressure approximately equal to the suction pressure;
passing a minor portion of the refrigerant passing through the refrigerant circuit through an expander to partially expand to a second pressure greater than the first pressure and intermediate the suction pressure and the discharge pressure; and
selectively passing the minor portion of partially expanded refrigerant through the second pass of the economizer heat exchanger and thence into an intermediate pressure stage of said compression device.
18. A method as recited in claim 17 further comprising the step of controlling the amount of refrigerant in the minor portion of partially expanded refrigerant flow passed through the second pass of the economizer heat exchanger and thence into an intermediate pressure stage of said compression device.
19. A method as recited in claim 17 further comprising the step of selectively injecting refrigerant liquid from the refrigerant circuit into an intermediate pressure stage of said compression device.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
We claim:
1. An optical device comprising:
a surface-mountable optical component comprising a base member having a recess filled with a transparent filler, and an VCSEL element arranged in the recess; and
a receptacle attached to the surface-mountable optical component, for receiving an optical fiber, thereby to optically connect the VCSEL element with the optical fiber.
2. The optical device of claim 1, wherein the surface-mountable optical component further comprises one or more optoelectronic monitor elements arranged in the recess of the base member, for monitoring a predetermined emission parameter of the VCSEL.
3. The optical device of claim 2, wherein the predetermined emission parameter is the power of light emitted by the VCSEL element.
4. The optical device of claim 1, further comprising:
a reflector arranged between the VCSEL element and a light receiving end of the receptacle, for reflecting part of the light emitted by the VCSEL element onto at least one of the one or more optoelectronic monitor elements.
5. The optical device of claim 4, wherein the VCSEL element and the one ore more optoelectronic monitor elements are mounted to a bottom surface of the recess adjacent to one another, and the reflecting surface of the reflector is at an angle relative to the bottom surface of the recess thereby to reflect light emitted from the VCSEL element onto at least one of the one or more optoelectonic monitor elements.
6. The optical device of claim 4, wherein the surface of the reflector facing the light receiving end of the receptacle is convex.
7. The optical device of claim 1, wherein the receptacle comprises an optical coupling element inbetween the optical fiber and the VCSEL element, for focussing light from the VCSEL element onto the light receiving end surface of an optical fiber receieved in the receptacle.
8. The optical device of claim 7, wherein the optical coupling element comprises a lens.
9. The optical device of claim 7, wherein receptacle comprises a recess for holding the lens.
10. The optical device of claim 8, wherein the lens is spherical.
11. The optical device of claim 7, wherein the optical coupling element is in contact with the filler.
12. The optical device of claim 7, wherein the light receiving end portion of the receptacle is transparent to optically connect the VCSEL element with an optical fiber received in the receptacle, and part of the surface of the transparent end portion facing the VCSEL, andor part of the surface of the transparent end portion facing the light receiving end surface of an optical fiber received in the receptacle, is convex, thereby to form the optical coupling element.
13. The optical device of claim 2, wherein the receptacle comprises an optical coupling element inbetween the optical fiber and the VCSEL element, for focussing light from the VCSEL element onto the light receiving end surface of an optical fiber received in the receptacle, and the surface of the optical coupling element facing the VCSEL element is reflective to reflect part of the light emitted from the VCSEL element on at least one of the one or more optoelectronic monitor elements.
14. The optical device of claim 1, further comprising:
an attachment element through which the surface-mountable optical component is attached to the receptacle, the attachment element comprising a through hole, wherein the surface-mountable optical compenent is arranged at one end of the through hole, and the receptacle is arranged at the other end of the through hole, whereby the optoelectronic element is optically connected to an optical fiber received in the receptacle.
15. The optical device of claim 14, wherein the receptacle and the surface-mountable optical component are glued to opposing surfaces of the attachment element, respectively.
16. The optical device of claim 2, further comprising:
a reflector arranged between the VCSEL element and a light receiving end of the receptacle, for reflecting a part of the light emitted by the light emitter onto at least one of the one or more optoelectronic monitor elements; and
an attachment element through which the surface-mountable optical component is attached to the receptacle, the attachment element comprising a through-hole, wherein the surface-mountable optical compenent is arranged at one end of the through hole, and the receptacle is arranged at the other end of the through hole, whereby the VCSEL element is optically connected to the optical fiber, and wherein the reflector is held in the through hole.
17. The optical device of claim 1, wherein the receptacle comprises plastic, metal andor ceramic material.
18. The optical device of claim 7, wherein the optical coupling element comprises transparent plastic andor glas material.
19. The optical device of claim 1, wherein the filler comprises a hardenable sealing compound.
20. The optical device of claim 19, wherein the filler conprises epoxy resin.
21. A surface-mountable optical component comprising a base member having a recess filled with a transparent filler, and a VCSEL arranged in the recess.