WO2017134567A1

WO2017134567A1 - Improved refrigeration compressor and layout

Info

Publication number: WO2017134567A1
Application number: PCT/IB2017/050529
Authority: WO
Inventors: Trilok KATARIA
Original assignee: Kataria Trilok
Priority date: 2016-02-06
Filing date: 2017-02-01
Publication date: 2017-08-10

Abstract

The present disclosure relates to an improved compressor comprising a plurality of cylinders housed within a common block such that these cylinders discharge their output to a common output. The compressor can comprise a plurality of motors such that each of the plurality of cylinders is powered by an independent motor, and compressor and motors make one compact and single unit. In an alternate embodiment, there can be a single common motor to power the plurality of cylinders through a common crank shaft and the common motor is positioned separate from the compressor. Also disclosed is an improved layout for refrigeration system wherein common motor of compressor is also used to power evaporator fan and condenser fan mounted on a common shaft through a pulley and belt arrangement.

Description

IMPROVED REFRIGERATION COMPRESSOR AND LAYOUT

TECHNICAL FIELD

[0001] The present disclosure relates to the field of refrigeration. In particular, the present disclosure pertains to an improved compressor for use in refrigeration systems and an improved lay out for the refrigeration system.

BACKGROUND

[0002] Background description includes information that may be useful in understanding the present invention. It is not an admission that any of the information provided herein is prior art or relevant to the presently claimed invention, or that any publication specifically or implicitly referenced is prior art.

[0003] In view of environmental effects of ever increasing power consumption by the world, reducing mankind's dependence on power based on fossil fuels is a thrust area. However, till such time technology for generating electricity that does not depend on fossil fuels is found, efforts have to be directed towards improvements in efficiency of power usages.

[0004] One area that consumes considerable amount of electric power is refrigeration that is used to cool homes and commercial spaces and provide other conveniences such as cool drinking water, refrigerating food items etc. Major part of such refrigeration systems are low capacity refrigeration systems such as window air conditioners, refrigerators, water coolers etc. used in homes and other places. Such systems and even larger refrigeration systems typically use a single cylinder compressor. The small capacity systems in particular have single cylinder compressors with integral motor (sealed unit) to make the system compact and temper proof. However, such systems have low power efficiency on account of motor having to work in uncooled environment and sub optimal compressor design.

[0005] Large capacity refrigeration systems such as those employed in cold storage, large industrial/commercial buildings, rail coach air conditioners etc. that may use more than one cylinder, typically deploy them in multistage configuration wherein output from one cylinder is fed to other to achieve a higher pressure. [0006] It is felt that a considerable improvement in power efficiency and thereby reduction in power consumption is possible by optimizing the design and layout of such refrigeration systems in general and compressor in particular.

[0007] There is therefore a need of providing an efficient layout or small capacity refrigeration systems and optimizing the design of compressors for reduction in power consumption and to effect overall economy.

[0008] All publications herein are incorporated by reference to the same extent as if each individual publication or patent application were specifically and individually indicated to be incorporated by reference. Where a definition or use of a term in an incorporated reference is inconsistent or contrary to the definition of that term provided herein, the definition of that term provided herein applies and the definition of that term in the reference does not apply.

[0009] In some embodiments, numerical parameters set forth in the written description and attached claims are approximations that can vary depending upon the desired properties sought to be obtained by a particular embodiment. In some embodiments, the numerical parameters should be construed in light of the number of reported significant digits and by applying ordinary rounding techniques. Notwithstanding that the numerical ranges and parameters setting forth the broad scope of some embodiments of the invention are approximations, the numerical values set forth in the specific examples are reported as precisely as practicable. The numerical values presented in some embodiments of the invention may contain certain errors necessarily resulting from the standard deviation found in their respective testing measurements.

[0010] As used in the description herein and throughout the claims that follow, the meaning of "a," "an," and "the" includes plural reference unless the context clearly dictates otherwise. Also, as used in the description herein, the meaning of "in" includes "in" and "on" unless the context clearly dictates otherwise.

[0011] The recitation of ranges of values herein is merely intended to serve as a shorthand method of referring individually to each separate value falling within the range. Unless otherwise indicated herein, each individual value is incorporated into the specification as if it were individually recited herein. All methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The use of any and all examples, or exemplary language (e.g. "such as") provided with respect to certain embodiments herein is intended merely to better illuminate the invention and does not pose a limitation on the scope of the invention otherwise claimed. No language in the specification should be construed as indicating any non-claimed element essential to the practice of the invention.

[0012] Groupings of alternative elements or embodiments of the invention disclosed herein are not to be construed as limitations. Each group member can be referred to and claimed individually or in any combination with other members of the group or other elements found herein. One or more members of a group can be included in, or deleted from, a group for reasons of convenience and/or patentability. When any such inclusion or deletion occurs, the specification is herein deemed to contain the group as modified thus fulfilling the written description used in the appended claims.

OBJECTS OF THE INVENTION

[0013] A general object of the present disclosure is to provide power efficient compressors.

[0014] An object of the present disclosure is to provides a multi-cylinder compressor to cater to high output requirements with improved power efficiency.

[0015] Another object of the present disclosure is to provide a multi-cylinder compressor with improved lubrication system.

[0016] Another object of the present disclosure is to provide a multi-cylinder compressor that is simple to manufacture and service.

[0017] Another object of the present disclosure is to provide an air conditioner layout that reduces power consumption.

SUMMARY

[0018] Aspects of the present disclosure relate to compressors. In particular, they pertain to refrigerant compressors with high output to meat high refrigeration tonnage requirement.

[0019] In an aspect, the present disclosure provides a multi-cylinder compressor with plurality of cylinders housed within a common block.

[0020] In an embodiment, the multiple cylinders can be powered by a common motor through a common crank shaft and can have a common lubrication system.

[0021] In an alternate embodiment, each of the plurality of cylinders housed within a single block can be powered by plurality of motors so that there is an independent motor to power each cylinder. In an aspect, independent motors coupled with each cylinder results in lowering power requirement as against use of a common motor on account of saving in frictional losses that take place in a single common crank shaft.

[0022] In an aspect, each cylinder is configured with an independent lubrication system to cater to lubrication needs of the corresponding cylinder. In an aspect, independent lubrication system for each cylinder enables use of readily available reliable lubrication arrangement and ensures reliable functioning.

[0023] In an embodiment, the present disclosure provides a layout for refrigeration system where common motor used for running the multi-cylinder compressor is also used to power condenser fan, thereby optimizing power consumption besides simplifying the layout and making it cost effective.

[0024] Various objects, features, aspects and advantages of the inventive subject matter will become more apparent from the following detailed description of preferred embodiments, along with the accompanying drawing figures in which like numerals represent like components

BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The accompanying drawings are included to provide a further understanding of the present disclosure, and are incorporated in and constitute a part of this specification. The drawings illustrate exemplary embodiments of the present disclosure and, together with the description, serve to explain the principles of the present disclosure.

[0026] FIG. 1 illustrates an exemplary schematic view of a multi-cylinder compressor having independent motor for each cylinder in accordance with embodiments of the present disclosure.

[0027] FIG. 2 illustrates an exemplary schematic view of a multi-cylinder compressor having a common motor for in accordance with embodiments of the present disclosure.

[0028] FIG. 3 illustrates an exemplary schematic view of an optimized layout for refrigeration system for improved power efficiency in accordance with embodiments of the present disclosure.

DETAILED DESCRIPTION

[0029] The following is a detailed description of embodiments of the disclosure depicted in the accompanying drawings. The embodiments are in such detail as to clearly communicate the disclosure. However, the amount of detail offered is not intended to limit the anticipated variations of embodiments; on the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the present disclosure as defined by the appended claims.

[0030] Each of the appended claims defines a separate invention, which for infringement purposes is recognized as including equivalents to the various elements or limitations specified in the claims. Depending on the context, all references below to the "invention" may in some cases refer to certain specific embodiments only. In other cases it will be recognized that references to the "invention" will refer to subject matter recited in one or more, but not necessarily all, of the claims.

[0031] Various terms as used herein are shown below. To the extent a term used in a claim is not defined below, it should be given the broadest definition persons in the pertinent art have given that term as reflected in printed publications and issued patents at the time of filing.

[0032] The present disclosure relates to an optimized compressor and an improved refrigeration layout for low capacity refrigeration systems. In another aspect, the disclosed layout and compressor can result in improved power efficiency resulting in reduced power consumption effecting overall economy and reduced carbon footprint.

[0033] It is to be appreciated that though various embodiments of the present disclosure have been described with reference to refrigerant compressor, they can with suitable modifications as would be evident to those skilled in art can as well be applied to other applications such as compressors and pumps for any fluid and all such applications are well within the scope of the present disclosure without any limitations whatsoever.

[0034] In an aspect, the present disclosure provides an optimized multi cylinder compressor with a plurality of cylinders configured within a single block and all the cylinders discharging the refrigerant at a common desired pressure. In another aspect use of more than one cylinder can improve the efficiency of the compressor compared to a single cylinder compressor of same capacity.

[0035] In an embodiment, plurality of cylinders of the multi-cylinder compressor of the present disclosure can be powered by independent motors through independent crank shafts. In an embodiment, the compressor having plurality of cylinders powered by plurality of motors can have means to synchronize position and movement of different pistons so that unbalance inertia forces and output/suction is evened out. These means can be electrical switching circuit and position sensors to keep the pistons in such relative positions as to minimize the unbalanced inertia forces and smoothen flow of fluid being sucked and discharged by the cylinders.

[0036] In an embodiment, each of the plurality of cylinders can also include independent lubrication system but a common oil sump storing and supplying lubrication oil for each of the plurality of cylinders.

[0037] In an alternate embodiment, the plurality of cylinders of the disclosed multi- cylinder compressor can be powered by a common motor through a common crank shaft. In case there are two cylinders, the two cylinders can work in opposite phases i.e. when first cylinder is compressing the refrigerant other cylinder can be in suction mode thus reducing pressure variation in the discharged refrigerant. It is to be appreciated that when more than two cylinders are used, they can be appropriately configured to minimize the pressure and torque fluctuations as would be known to a person skilled in the art.

[0038] In an embodiment, the disclosed multi-cylinder compressor powered by common motor through common crank shaft can have a common lubrication system including a common lubrication pump drawing lubrication oil from a common sump and supplying lubrication oil to each of the cylinders.

[0039] It is to be appreciated that the disclosed compressor employs a concept that is different from multi stage compressors that employ more than one cylinder in a cascading configuration i.e. output of one is fed to next to increase the output pressure. Such a multi stage configuration will typically have cylinders of different volume as each successive cylinder is required to handle smaller volume. They may therefore be independently running compressors run by different motors without a need to synchronize their rotation. On the contrary, cylinders of the disclosed compressor are of same size, each contributing to flow of the refrigerant and run by a common crank shaft and a common prime mover in a synchronized manner to optimize pressure fluctuation at the output.

[0040] In another aspect, outlets of the cylinders can be connected to a discharge manifold that can be configured to reduce resistance to flow of the refrigerant and thereby improving volumetric efficiency of the each of the cylinders of the compressor. In another aspect, having more cylinders for handling same amount of refrigerant reduces flow of the refrigerant through the respective discharge ports reducing resistance to the flow thereby improving efficiency. As can be appreciated, multi cylinder compressor with multi stage configuration do not have the above advantage and therefore the disclosed configuration helps in optimizing the performance of the compressor as compared to multi stage multi cylinder compressors known in the art. [0041] In another embodiment, the disclosed multi-cylinder compressor powered by common motor through common crank shaft can have the common motor positioned separately from the compressor. In another aspect, keeping the motor and the compressor as two separate assemblies and physically separated can allow the motor to work in a cooler environment thereby improving its efficiency and reducing the power consumption. This is especially applicable to small capacity refrigeration systems such as domestic air conditioners, domestic refrigerators, water coolers, car air conditioners to name a few.

[0042] In an embodiment, the separately placed motor can also be used to drive condenser and evaporator fans of the refrigeration doing away with requirement of separate motors for these functions thereby reducing number of parts and effecting overall economy.

[0043] In another aspect, to improve the efficiency of the refrigeration system the layout of the system can be optimized by eliminating the connecting part between the throttling device such as a capillary tube and the evaporator and connecting the throttling device directly to the evaporator. In another aspect elimination of the connecting part can reduce waste of the cooling capacity of the system.

[0044] In another aspect, elimination of the connecting part between the throttling device such as a capillary tube and the evaporator can result in reduced requirement of the refrigerant.

[0045] In another aspect, the refrigeration system can incorporate a High Efficiency Particulate Arrestance (HEPA) filter of an appropriate class such as E10, El l or E12 configured before the evaporator to meet the application requirement. In another aspect, HEPA filter can, besides providing cleaner environment by improving filtering efficiency, help in reducing resistance to flow of air thereby reducing power drawn by the evaporator fan, increasing turbulence in air passing through the evaporator thereby improving the heat transfer efficiency and improve heat transfer by reducing deposits of dust on the evaporator.

[0046] It is to be appreciated that various embodiments of the present disclosure i.e. a multi cylinder compressor, a separately placed motor, a common motor for driving the compressor and the fans, HEPA filter at inlet of the evaporator, can be implemented independently or in combination with each other, irrespective of capacity of the system, depending on configuration and requirements of the system without any limitations and each of them can result in deriving corresponding benefits.

[0047] Referring now to FIG. 1 wherein an exemplary improved compressor 100 is disclosed. The improved compressor 100 can comprise plurality of cylinders such as 102-1 and 102-2 (collectively referred to as cylinders 102 hereinafter) with corresponding pistons 104-1 and 104-2 (collectively referred to as cylinders 104 hereinafter) respectively, of appropriate volume to collectively handle the requisite flow rate of the refrigerant. Each of the cylinders can be powered by independent motors such as motors 106-1 and 106-2. It is to be appreciated that though the exemplary embodiment of FIG. 1 shows only two cylinders, it is possible to have any number of cylinders with corresponding motors without any limitation depending on total flow of the refrigerant required by the system to optimize the performance.

[0048] In another aspect the two cylinders 102 can have a common discharge/outlet 108 and a common suction/inlet 110; and the inlet 110 and outlet 108 can be configured to provide least resistance to flow of the refrigerant so as to improve the efficiency of the compressor 100.

[0049] In an aspect, each of the plurality of motors 106 can be housed within the compressor assembly 100 to make a compact single unit.

[0050] In an embodiment, the compressor having plurality of cylinders powered by plurality of motors can have means (not shown here) to synchronize position and movement of different pistons so that unbalance inertia forces and output/suction is evened out. These means can be electrical switching circuit and position sensors to keep the pistons in such relative positions as to minimize the unbalanced inertia forces and smoothen flow of fluid being sucked and discharged by the cylinders so that volumetric efficiency of the compressor is not compromised by high flow rate on account of all or many cylinders sucking/discharging at the same time.

[0051] For example there can be sensors to sense position of each of the pistons, and a controller operatively coupled to the sensors and the motors and configured to control rotation of the motors so that pistons are in positions relative to each other as desired.

[0052] FIG. 2 illustrates an exemplary schematic arrangement of a multi-cylinder compressor powered by common motor in accordance with an embodiment of the present disclosure. The compressor 200 can comprise plurality of cylinders such as 202-1 and 202-2, of appropriate volume to collectively handle the requisite flow rate of the refrigerant. It is to be appreciated that though the exemplary embodiment of FIG.2 as in FIG. 1, shows the compressor comprising of two cylinders, it is possible to have compressor with more than two cylinders depending on total flow of the refrigerant required by the system without any limitation to optimize the performance.

[0053] In another aspect, respective pistons 204-1 and 204-2 of the two cylinders 202-1 and 202-2 can be placed in mutually opposed phases such that when one is compressing the refrigerant the other is in suction stroke. This can minimize pressure variation in the discharged refrigerant. It is to be appreciated that in configurations having more than two cylinders, the cylinders can be appropriately placed to minimize the pressure variation and smoothen the torque on the motor driving the compressor.

[0054] In another aspect, there can be a common motor 206 to drive the two cylinders 202-1 and 202-2 through a crank shaft and the motor 206 can be a separate assembly placed away from the compressor cylinders 102. In another aspect placing the motor separately can provide a cooler working environment for the motor 106 improving its efficiency.

[0055] As in case of compressor 100, the two cylinders 202 can have a common discharge/outlet 208 and a common suction/inlet 210; and the inlet 210 and outlet 208 can be configured to provide least resistance to flow of the refrigerant so as to improve the efficiency of the compressor 200.

[0056] FIG. 3 illustrates an exemplary layout of the refrigeration system 300 of the present disclosure. Shown therein is motor 302 connected to the compressor 304 and also driving evaporator fan 306 and condenser fan 308. In an embodiment, the evaporator fan 306 and the condenser fan 308 can be mounted on a common shaft 310 and driven by a pulley 312 through a belt 314.

[0057] In another aspect, the refrigeration system 300 can incorporate a HEPA filter 316 at the inlet side of the evaporator 318. In another aspect the HEPA filter can, besides providing cleaner environment by improving filtering efficiency, help in reducing resistance to flow of air thereby reducing power drawn by the evaporator fan 306, increasing turbulence in air passing through the evaporator thereby improving the heat transfer efficiency and improve heat transfer by reducing deposits of dust on the evaporator 318.

[0058] In another aspect, to improve the efficiency of the refrigeration system 300 the layout of the system 300 can be optimized by eliminating the connecting part between the throttling device such as a capillary tube 320 and the evaporator 318 and connecting the capillary 320 directly to the evaporator 318. In another aspect elimination of the connecting part can reduce waste of the cooling capacity of the system.

[0059] In another aspect, the refrigeration system 300 of the present disclosure elimination of the connecting part between the capillary tube 320 and the evaporator 318 which can also result in reduced requirement of the refrigerant.

[0060] The present disclosure thus provides an improved compressor for optimum efficiency in respect of power consumption that can be used in any application such as low capacity refrigeration systems like, domestic air conditioners, refrigerators, water coolers, car air conditioners as well as in large capacity refrigeration systems for example those used in cold storages, large industrial/commercial buildings, railway coaches to name a few. Various embodiments of the disclosure can be implemented independently or in combination without any limitation to derive corresponding benefits in respect of power consumption.

[0061] It should be appreciated that the concept of multi cylinder compressor can also be used in applications other than refrigeration systems such as those for compressors used in industrial processes without any limitations and compromise on benefits.

[0062] While the foregoing describes various embodiments of the invention, other and further embodiments of the invention may be devised without departing from the basic scope thereof. The scope of the invention is determined by the claims that follow. The invention is not limited to the described embodiments, versions or examples, which are included to enable a person having ordinary skill in the art to make and use the invention when combined with information and knowledge available to the person having ordinary skill in the art.

ADVANTAGES OF THE INVENTION

[0063] The present disclosure provides power efficient compressors.

[0064] The present disclosure provides a multi-cylinder compressor to cater to high output requirements with improved power efficiency.

[0065] The present disclosure provides a multi-cylinder compressor with improved lubrication system.

[0066] The present disclosure provides a multi-cylinder compressor that is simple to manufacture and service.

[0067] The present disclosure provides an air conditioner layout that reduces power consumption.

Claims

A compressor comprising:

a plurality of cylinders housed within a common block:

a common input connected to input of each of the plurality of cylinders; and a common output connected to output of each of the plurality of cylinders.

The compressor as claimed in claim 1, wherein the compressor further comprises a plurality of motors such that each of the plurality of cylinders is powered by an independent motor.

The compressor as claimed in claim 2, wherein the compressor further comprises means to synchronize position and movement of a plurality of pistons of the plurality of cylinders to minimize unbalanced inertia forces and to smoothen flow of fluid being sucked and discharged by the cylinders so that volumetric efficiency of the compressor is not compromised by high flow rate on account of all or many of the cylinders sucking and discharging at the same time.

The compressor as claimed in claim 3, wherein the compressor and the plurality of motors make one compact and single unit.

The compressor as claimed in claim 2, wherein each of the plurality of cylinders has independent lubrication system drawing lubrication oil from a common oil sump.

The compressor as claimed in claim 1, wherein the compressor comprises a single common motor to power the plurality of cylinders through a common crank shaft.

The compressor as claimed in claim 6, wherein the common motor to power the plurality of cylinders is positioned separate from the compressor.

The compressor as claimed in claim 6, wherein the compressor has a common lubrication system drawing lubrication oil from a common oil sump using a common oil pump.

The compressor as claimed in claim 7, wherein the compressor is used in a refrigeration system, the refrigeration system comprising an evaporator fan and a condenser fan, wherein the common motor also drives the evaporator fan and the condenser fan.

The compressor as claimed in claim 9, wherein the evaporator fan and the condenser fan are mounted on a common shaft and the common shaft is driven by the common motor through a belt and a pulley mounted on the common shaft.