Patent Publication Number: US-10760558-B2

Title: Multistage compressor with magnetically actated compression stage

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application claims the benefit of priority from U.S. Provisional Patent Application Ser. No. 62/394,412, filed on Sep. 14, 2016, and entitled “MULTISTAGE SILICONE COMPRESSOR,” which is incorporated herein by reference in its entirety. 
    
    
     TECHNICAL FIELD 
     The present disclosure generally relates to compressors, particularly to multistage compressors, and more particularly to oil-free compressors. 
     BACKGROUND 
     Conventional compressors have various disadvantages, particularly when it comes to applications, such as gas compression for medical use. For example, relatively large, heavy, noisy and inefficient compressors are not suitable for medical applications where using oil is prohibited in the gas compression systems. Furthermore, in areas such as dental clinics and hospitals, quiet gas compressors are preferable. There is, therefore, a need in the art for quiet compressors with simple oil-free designs without relatively complicated timing and valve connections. 
     SUMMARY 
     This summary is intended to provide an overview of the subject matter of the present disclosure, and is not intended to identify essential elements or key elements of the subject matter, nor is it intended to be used to determine the scope of the claimed embodiments. The proper scope of the present disclosure may be ascertained from the claims set forth below in view of the detailed description below and the drawings. 
     The present disclosure is directed to a multistage compressor that may include a wobbling member operationally coupled with an external power source. The external power source may drive a nutating motion of the wobbling member. The multistage compressor may further include a plurality of flexible chambers connected to the wobbling member, each flexible chamber including a respective intake passage and a respective discharge passage. The wobbling member may sequentially press down and pull up the plurality of flexible chambers. The multistage compressor may further include a one-way valve in each respective intake passage and gas may be drawn into each flexible chamber through the respective one-way valve of each flexible chamber as the wobbling member pulls up each flexible chamber. The gas may then be compressed to a higher pressure as the wobbling member presses down each flexible chamber and compressed gas may be discharged through the respective discharge passage of each flexible chamber. 
     According to some exemplary embodiments, the multistage compressor may further include a magnetically actuated compression stage that may receive the compressed gas gathered from the flexible chambers and further compress the gas to a higher pressure. The magnetically actuated compression stage may include an elongated cylinder with an inlet port and an outlet port, a bobbin disposed inside the elongated cylinder, and a reciprocating member mounted for reciprocating movement in the bobbin. The reciprocating member may include a permanent magnet and it may sealably engage an inner surface of the bobbin. The magnetically actuated compression stage may further include a controller coupled with the bobbin for sequentially changing polarity of the bobbin to generate a reciprocating magnetic field that drives the permanent magnet reciprocally through the elongated cylinder such that the compressed gas is alternatively drawn into the elongated cylinder from the inlet port and is further compressed and discharged from the outlet port. 
     According to an exemplary embodiment, the wobbling member may include a plurality of extended tongues, where each flexible chamber of the plurality of flexible chambers may be attached to a corresponding extended tongue of the plurality of extended tongues. According to another embodiment, the plurality of extended tongues may include three extended tongues spaced apart by 120°. 
     According to an exemplary embodiment, the wobbling member may include a disk and each flexible chamber of the plurality of flexible chambers may be attached to periphery of the disk. According to some exemplary embodiments, the wobbling member may include a disk, wherein three flexible chambers may be attached to periphery of the disk spaced apart by 120°. 
     According to an exemplary embodiment, the flexible chambers may share a flange in a form of a base plate. The one-way valve of each flexible chamber may be integrally formed on the base plate. According to an exemplary embodiment, the one-way valve of each flexible chamber may include a flexible tongue bendable in one direction, wherein the flexible tongue is cut into the base plate. 
     According to an exemplary embodiment, the flexible chambers, the base plate, and the one-way valves may be formed as an integrated flexible assembly out of a flexible material. According to an exemplary embodiment, the intake passage and the discharge passage of each flexible chamber may be formed on a first cap that may be attached sealably and immediately under the integrated flexible assembly. According to an exemplary embodiment, the plurality of flexible chambers may include flexible cups made of a flexible polymeric material. 
     Other systems, methods, features and advantages of the embodiments will be, or will become, apparent to one of ordinary skill in the art upon examination of the following figures and detailed description. It is intended that all such additional systems, methods, features and advantages be included within this description and this summary, be within the scope of the embodiments, and be protected by the following claims. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The drawing figures depict one or more embodiments in accord with the present teachings, by way of example only, not by way of limitation. In the figures, like reference numerals refer to the same or similar elements. 
         FIG. 1  illustrates a sectional perspective view of a multistage compressor, consistent with exemplary embodiments of the present disclosure; 
         FIG. 2  illustrates a wobbling member assembly, consistent with one or more exemplary embodiments of the present disclosure; 
         FIG. 3  illustrates a perspective view of flexible chambers, consistent with one or more exemplary embodiments of the present disclosure; 
         FIG. 4  is a schematic representation of a flexible chamber, consistent with one or more exemplary embodiments of the present disclosure; 
         FIG. 5  shows a sectional left view of a flexible one-way valve, consistent with one or more exemplary embodiments of the present disclosure; 
         FIG. 6  illustrates an exploded view of flexible chambers, a first cap, and a guiding cap, consistent with one or more exemplary embodiments of the present disclosure; 
         FIG. 7  illustrates a perspective view of a first cap, consistent with one or more exemplary embodiments of the present disclosure; 
         FIG. 8  illustrates a perspective view of a guiding cap, consistent with one or more the exemplary embodiments of the present disclosure; 
         FIG. 9  illustrates a sectional perspective view of a magnetically actuated positive displacement compressor, consistent with one or more exemplary embodiments of the present disclosure; and 
         FIG. 10  illustrates an exploded view of a magnetically driven compressor, consistent with one or more exemplary embodiments of the present disclosure. 
     
    
    
     DETAILED DESCRIPTION 
     In the following detailed description, numerous specific details are set forth by way of examples in order to provide a thorough understanding of the relevant teachings. However, it should be apparent that the present teachings may be practiced without such details. In other instances, well known methods, procedures, components, and/or circuitry have been described at a relatively high-level, without detail, in order to avoid unnecessarily obscuring aspects of the present teachings. 
     Disclosed herein is a multistage compressor for compressing gas or any other gaseous matters or fluids such as carbon dioxide, refrigerants and the like. For ease of reference, the gaseous fluid to be compressed is hereinafter simply referred to as gas. The multistage compressor may include a number of compression stages. In a first compression stage, the gas may be compressed in a positive displacement compressor, where the gas may be drawn in and captured in a number of flexible chambers and then a wobbling member may be utilized to reduce the volume of the flexible chambers to compress the gas from the first pressure to an intermediate pressure. In a second compression stage, the gas may be further compressed from the intermediate pressure to a second higher pressure in a magnetically actuated compression stage, where a magnetic field may be utilized to drive a permanent magnet member reciprocally inside a cylindrical chamber. Utilizing flexible chambers in combination with the wobbling member in the first compression stage and the magnetically actuated positive displacement compressor in the second compression stage may enable the disclosed multistage compressor to function as a relatively quiet and oil-free compressor, which may be suitable for applications where clean gas and/or silence are important. 
       FIG. 1  illustrates a sectional perspective view of a multistage compressor  100 , consistent with one or more exemplary embodiments of the present disclosure. Multistage compressor  100  may include a first compression stage  101  and a second compression stage  102 . In first compression stage  101 , a wobbling member  103  is connected to a number of flexible chambers  104  that may be formed as a number of flexible polymeric cups. Wobbling member  103  may be operationally coupled with an external power source  105  that may be a mechanical source of rotary power, such as an electric motor  106 . External power source  105  may drive the nutating motion of wobbling member  103  as will be described later in this disclosure. As wobbling member  103  nutates, it may transform rotational movement of electric motor  106  to a reciprocating motion through which flexible chambers  104  may be pressed down one after another and then pulled up again by wobbling member  103 . Flexible chambers  104  may form expandable and collapsible compressing chambers that may be pressed down by wobbling member  103  in order to compress the gas trapped therein and may be pulled up by wobbling member  103  in order to draw the gas into flexible chambers  104 . As wobbling member  103  presses down a flexible chamber, such as flexible chamber  107 , available volume under flexible chamber  107  may be reduced and thereby gas trapped under flexible chamber  107  may be compressed. Compressed gas may be discharged from under each flexible chamber, such as flexible chamber  107  through a discharge passage (obscured from view in  FIG. 1 ) under flexible chamber  107 . As wobbling member  103  pulls up a flexible chamber, such as flexible chamber  108 , available volume under flexible chamber  108  may be increased and gas may be sucked or drawn into flexible chamber  108  via an intake passage. Gas may be drawn in under flexible chambers  104  via the intake passages through one-way valves  109  that only allow the gas to be drawn inside flexible chambers  104 . First compression stage  101  may be disposed within a first chamber  141 . The gas may enter first compression stage  101  through a one-way valve  162 . 
       FIG. 2  illustrates a wobbling member assembly, consistent with one or more the exemplary embodiments of the present disclosure. Wobbling member  103  may be coupled to a drive shaft  110  of electric motor  106  by a crank pin  111  that may be eccentrically coupled with drive shaft  110  by a coupling member  112 . Coupling member  112  may be a crank and drive shaft  110  may be fixed inside a first receiving hole  113  of coupling member  112  by, for example a key coupling (not explicitly shown in  FIG. 2 ). One end of crank pin  111  may be received inside a second angled receiving hole  114  of coupling member  112  and may be rotationally disposed inside second angled receiving hole  114  of coupling member  112  with at least one bearing  115 . According to another embodiment, two bearings may be utilized, where the bearings are disposed from each other at a distance to provide a stable support of crank pin  111 . An opposite end of crank pin  111  may be disposed on wobbling member  103  by a coupling member  116  and crank pin  111  may be key coupled with wobbling member  103 . The rotational movement of electric motor  106  may be transferred to wobbling member  103  through a Z-shaped shaft that may be formed by drive shaft  110 , coupling member  112  and crank pin  111 . With this configuration, the rotation of drive shaft  110  by electric motor  106  causes wobbling member  103  to perform a nutating and non-rotating motion. As used herein, a nutating motion of wobbling member  103  means a wobbling motion without rotation of wobbling member  103  about its normal axis. Referring to  FIG. 2 , crank pin  111  may be disposed on the normal axis of wobbling member  103  and perpendicular to a plane containing wobbling member  103 . 
       FIG. 3  illustrates a perspective view of flexible chambers  104 , consistent with one or more exemplary embodiments of the present disclosure. Flexible chambers  104  may be similar in size and shape. Referring to  FIG. 3 , flexible chambers  104  may include flexible polymeric cups that may be, for example, made of silicone or rubber. Flexible chambers  104  may be open at their base ends and on their opposite ends, threaded rods  119  may be secured that may function as fastening members to connect flexible chambers  104  to wobbling member (not shown in  FIG. 3 ). 
     Referring to  FIG. 3 , flexible chambers  104  may share a flange in a form of a base plate  120 . One-way valves  109  (one of which is obscured from view in  FIG. 3 ) may be formed on base plate  120 . According to some embodiments, flexible chambers  104 , base plate  120  and one-way valves  109  may be integrally formed as an integrated flexible assembly  163  out of a flexible material such as silicon or other flexible polymeric materials. 
     Referring to  FIG. 3 , one-way valves  109  may include flexible tongues  118  cut into base plate  120 , where flexible tongues  118  may bend in one direction, for example in directions shown by arrows  121  and their bending may be prohibited in other directions, thereby forming a one-way valve which will be described later in this disclosure. 
       FIG. 4  is a schematic representation of flexible chamber  108 , consistent with one or more exemplary embodiments of the present disclosure. Referring to  FIG. 4 , flexible chamber  108  may be connected to wobbling member  103  via a threaded rod  122  that may be similar to any of threaded rods  119 . There may be a receiving hole  123  near periphery of wobbling member  103 , through which threaded rod  122  may pass and be fastened to wobbling member  103  by a fastening member  124 . Referring back to  FIG. 1 , all flexible chambers  104  may be similarly connected to wobbling member  103 . 
     With further reference to  FIG. 1 , according to some exemplary embodiments, wobbling member  103  may have three extended tongues  125 , where each extended tongue has a respective receiving hole near its periphery, through which a respective flexible chamber may be fastened to the wobbling member as was described in more detail in connection with  FIG. 4 . Extended tongues  125  may be spaced apart by 120° and each of extended tongues  125  may be slightly curved upward. According to some embodiments, wobbling member  103  may be a disk with three spaced apart receiving holes near its edge, where the receiving holes are spaced apart by 120°. 
     With further reference to  FIG. 4 , a flexible chamber, such as flexible chamber  108  may be in gaseous fluid communication with an intake passage  126  and a discharge passage  127 . Gas may be drawn into flexible chamber  108  via intake passage  126  and compressed gas may be discharged from under flexible chamber  108  via discharge passage  127 . 
     Referring to  FIG. 6 , integrated flexible assembly  163  that includes integrally formed flexible chambers  104 , one-way valves  109 , and base plate  120  may be placed immediately above a first cap  130 . Intake passages  126 ,  128 , and  129  may be formed on first cap  130  as a number of grooves with a depth less than width  131  of first cap  130 . 
       FIG. 7  illustrates a perspective view of first cap  130 , consistent with one or more exemplary embodiments of the present disclosure. Referring to  FIG. 7 , each intake passage, for example, intake passage  126  may have two sections, an elongated groove section  132  and a curved groove section  133 . Discharge passages  127 ,  134 , and  135  may further be formed on first cap  130  as a number of holes under each flexible chamber. Referring to  FIGS. 4 and 7 , for example, holes  136  may be formed under flexible chamber  108 , a base-end profile of which is shown as circle  137  in  FIG. 7 . Holes  136  may function as discharge passage  127  for flexible chamber  108  and holes  136  extend through the entire width of first cap  130 . 
     Referring back to  FIG. 6 , once integrated flexible assembly  163  is, in an exemplary scenario, tightly placed above first cap  130  in a gas-tight attachment, the gas may only pass from above base plate  120  to an area under first cap  130  via discharge passages  127 ,  134 , and  135 . 
     Referring to  FIG. 6 , each one-way valve may be placed immediately above the curved groove section of a corresponding intake passage of a corresponding flexible chamber. For example, one-way valve  138  is immediately placed above a curved groove section  139  of intake passage  128 . Referring to  FIGS. 4 and 7 , elongated sections of the intake passages may be extended under flexible chambers. For example, elongated section  132  of intake passage  126  may be extended under flexible chamber  108  (not visible in  FIG. 7 , a base end profile of which is illustrated as circle  137 ). 
     With reference to  FIGS. 4 and 5 , in an exemplary scenario, once a flexible chamber, such as flexible chamber  108  is pressed down by wobbling member  103 , volume of flexible chamber  108  is reduced and the gas trapped under flexible chamber  108  may be compressed. The compressed gas may be discharged from under flexible chamber  108  through discharge passage  127 , which includes holes  136  under flexible chamber  108 . As wobbling member  103  continues its nutating motion, flexible chamber  108  may be pulled up by wobbling member  103 , which results in an increase in the volume available under flexible chamber  108  and as a result gas is sucked into flexible chamber  108  via intake passage  126 . As flexible chamber  108  is pulled up, gas will push down flexible one-way valve  109  and the gas will pass through intake passage  126  and will be trapped under flexible chamber  108 . As wobbling member  103  continues its nutating motion, once again, flexible chamber  108  is pressed down. Since flexible one-way valve  109  only allows gas to be sucked into intake passage  126  and prevents gas from being pushed out from under flexible chamber  108  through intake passage  126 , the only pathway available for the compressed gas is discharge passage  127 . 
       FIG. 5  shows a sectional left view of flexible one-way valve  109 , consistent with one or more exemplary embodiments of the present disclosure. Tongue  118  of flexible one-way valve  109  may bend downward as gas is being drawn into a flexible chamber, however, once the flexible chamber is pressed down by the wobbling member, since bending of tongue  118  is prohibited in an upward direction beyond the plane containing tongue  118 , the gas cannot exit through intake passage  126 . Referring back to  FIG. 1 , bending of tongue  118  may be prohibited in an upward direction beyond the plane containing tongue  118  by placing a portion of tongue  118  under wall of first chamber  141 . 
     Referring to  FIG. 6 , first cap  130  may be mounted on a guiding cap  142  in a gas-tight attachment.  FIG. 8  illustrates a perspective view of guiding cap  142 , consistent with one or more exemplary embodiments of the present disclosure. Guiding cap  142  may include a number of recessed chambers  143 ,  144 , and  145  that may be placed under respective flexible chambers. Compressed gas that may be discharged from a discharge passage under a flexible chamber may enter a corresponding recessed chamber on guiding cap  142 . After that, compressed gas gathered from all flexible chambers inside recessed chambers  143 ,  144 , and  145  may be guided through a number of grooves  146 ,  147 , and  148  that connect recessed chambers  143 ,  144 , and  145  with a central hole  149  on guiding cap  142 . Central hole  149  may be equipped with a one-way valve (not explicitly shown in  FIG. 8 ) that only allows the gas to be discharged to a next compression stage. 
     Referring to  FIGS. 4 and 8 , in an exemplary scenario, recessed chamber  143  may be placed under flexible chamber  108 . Compressed gas may be discharged through discharge passage  127  into recessed chamber  143  on guiding cap  142  and then it may move toward central hole  149  via groove  146  on guiding cap  142 . Recessed chambers  143 ,  144 , and  145  gather the compressed gas from all the flexible chamber and the gathered compressed gas may be guided via grooves  146 ,  147 , and  148  to central hole  149  and compressed gas with an intermediate pressure may be sent to the next stage of compression via the one-way valve installed in central hole  149 . 
     Referring back to  FIG. 1 , as mentioned before, in an exemplary embodiment, multistage compressor  100  may further include second compression stage  102  that may be a magnetically actuated compression stage.  FIG. 9  illustrates a sectional perspective view of a magnetically actuated compression stage  150  that may be utilized as second compression stage  102  (labeled in  FIG. 1 ). 
     Referring to  FIG. 9 , in an exemplary embodiment, magnetically actuated compression stage  150  may include an elongated cylinder  151  with an inlet port  152  that may be formed at an end wall  153  of cylinder  151 . Inlet port  152  may be in fluid communication with central hole  149  of guiding cap  142  (labeled and visible in  FIG. 8 ). The compressed gas from the first stage may pass through a one-way valve (not visible in  FIG. 9 ) and may enter the second stage through inlet port  152 . Magnetically actuated compression stage  150  may further include a reciprocating member  154  that may be made of a permanent magnet. Reciprocating member  154  may be mounted inside elongated cylinder  151  so that reciprocating member  154  may be reciprocally movable in directions shown by arrows  155  within elongated cylinder  151 . 
     Referring to  FIG. 9 , reciprocating member  154  may be driven within elongated cylinder  151  by a magnetic linear actuator. The magnetic linear actuator may include a winding  156  that is wound about a bobbin  157  (a section of an inner surface  158  of bobbin is illustrated in  FIG. 9 ). It should be understood that only a portion of wound wires are illustrated in  FIG. 9  for simplicity. Winding  156  may be connected to a controller  161  that may be programmed to energize winding  156  and sequentially change positive and negative poles of winding  156  thereby causing reciprocating member  154  to be driven up and down. 
     With further reference to  FIG. 9 , in an exemplary embodiment, reciprocating member  154  may have a generally circular cross-section, such that reciprocating member  154  sealably engages inner surface  158  of bobbin  157 . According to an exemplary implementation, reciprocating member  154  may be in a form of a permanent magnet interposed and sealed between supporting elements. Reciprocating member  154  should be slidable across inner surface  158  of bobbin  157  so that reciprocating member  154  moves freely up and down in elongated cylinder  151 . At the same time, the circumferential edges of reciprocating member  154  must provide a secure seal. 
     In an exemplary scenario, once the compressed gas from the first stage is introduced into elongated cylinder  151  through inlet port  152 , winding  156  may be energized by controller  161  such that reciprocating member  154  may be pulled down and the volume of elongated cylinder  151  may increase, whereby compressed gas from the first compression stage may be drawn into the cylinder  151 . When controller  161  changes positive and negative poles of winding  156 , reciprocating member  154  reverses direction and may be driven upward and the volume of cylinder  151  decreases thereby the compressed gas may be further compressed in the second stage from the intermediate pressure to the second higher pressure. The high pressure gas may exit through an outlet port  159  formed on a side wall of cylinder  151 . 
       FIG. 10  illustrates an exploded view of magnetically actuated compression stage  150 , consistent with one or more exemplary embodiments of the present disclosure. Referring to  FIG. 10 , second magnetically actuated compression stage may include elongated cylinder  151  with outlet port  159  formed on a side wall thereof and reciprocating member  154  disposed within bobbin  157 . Bobbin  157  may be a cylinder with flanges on which wire may be wound to from winding  156 . According to other embodiments, bobbin  157  may be without flanges. Reciprocating member  154  may be reciprocally movable inside bobbin  157 . 
     Referring to  FIGS. 9 and 10 , according to one exemplary embodiment, elongated cylinder  151  may be formed without top end wall  153 . A base end wall  160  may be attached to elongated cylinder  151  and guiding cap  142  may be mounted on top of elongated cylinder  151  in a gas-tight manner to form the second compression stage. 
     While the foregoing has described what are considered to be the best mode and/or other examples, it is understood that various modifications may be made therein and that the subject matter disclosed herein may be implemented in various forms and examples, and that the teachings may be applied in numerous applications, only some of which have been described herein. It is intended by the following claims to claim any and all applications, modifications and variations that fall within the true scope of the present teachings. 
     Unless otherwise stated, all measurements, values, ratings, positions, magnitudes, sizes, and other specifications that are set forth in this specification, including in the claims that follow, are approximate, not exact. They are intended to have a reasonable range that is consistent with the functions to which they relate and with what is customary in the art to which they pertain. 
     The scope of protection is limited solely by the claims that now follow. That scope is intended and should be interpreted to be as broad as is consistent with the ordinary meaning of the language that is used in the claims when interpreted in light of this specification and the prosecution history that follows and to encompass all structural and functional equivalents. Notwithstanding, none of the claims are intended to embrace subject matter that fails to satisfy the requirement of Sections 101, 102, or 103 of the Patent Act, nor should they be interpreted in such a way. Any unintended embracement of such subject matter is hereby disclaimed. 
     Except as stated immediately above, nothing that has been stated or illustrated is intended or should be interpreted to cause a dedication of any component, step, feature, object, benefit, advantage, or equivalent to the public, regardless of whether it is or is not recited in the claims. 
     It will be understood that the terms and expressions used herein have the ordinary meaning as is accorded to such terms and expressions with respect to their corresponding respective areas of inquiry and study except where specific meanings have otherwise been set forth herein. Relational terms such as first and second and the like may be used solely to distinguish one entity or action from another without necessarily requiring or implying any actual such relationship or order between such entities or actions. The terms “comprises,” “comprising,” or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. An element proceeded by “a” or “an” does not, without further constraints, preclude the existence of additional identical elements in the process, method, article, or apparatus that comprises the element. 
     The Abstract of the Disclosure is provided to allow the reader to quickly ascertain the nature of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims. In addition, in the foregoing Detailed Description, it can be seen that various features are grouped together in various implementations. This is for purposes of streamlining the disclosure, and is not to be interpreted as reflecting an intention that the claimed implementations require more features than are expressly recited in each claim. Rather, as the following claims reflect, inventive subject matter lies in less than all features of a single disclosed implementation. Thus, the following claims are hereby incorporated into the Detailed Description, with each claim standing on its own as a separately claimed subject matter. 
     While various implementations have been described, the description is intended to be exemplary, rather than limiting and it will be apparent to those of ordinary skill in the art that many more implementations and implementations are possible that are within the scope of the implementations. Although many possible combinations of features are shown in the accompanying figures and discussed in this detailed description, many other combinations of the disclosed features are possible. Any feature of any implementation may be used in combination with or substituted for any other feature or element in any other implementation unless specifically restricted. Therefore, it will be understood that any of the features shown and/or discussed in the present disclosure may be implemented together in any suitable combination. Accordingly, the implementations are not to be restricted except in light of the attached claims and their equivalents. Also, various modifications and changes may be made within the scope of the attached claims.