Abstract:
A compressor assembly having a tank seal which seals a tank gap between a portion of a housing of the compressor assembly and a portion of a compressed gas tank and a method for controlling the sound level of a compressor assembly by configuring a tank seal to seal a gap between the housing of a compressor assembly and a compressed gas tank. The sound level of the compressor assembly can be controlled by sealing a tank gap between at least a portion of a compressor assembly housing and at least a portion of a compressed gas tank.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This patent application claims benefit of the filing date under 35 USC §120 of copending U.S. provisional patent application No. 61/533,993 entitled “Air Ducting Shroud For Cooling An Air Compressor Pump And Motor” filed on Sep. 13, 2011. This patent application claims benefit of the filing date under 35 USC §120 of copending U.S. provisional patent application No. 61/534,001 entitled “Shroud For Capturing Fan Noise” filed on Sep. 13, 2011. This patent application claims benefit of the filing date under 35 USC §120 of copending U.S. provisional patent application No. 61/534,009 entitled “Method Of Reducing Air Compressor Noise” filed on Sep. 13, 2011. This patent application claims benefit of the filing date under 35 USC §120 of copending U.S. provisional patent application No. 61/534,015 entitled “Tank Dampening Device” filed on Sep. 13, 2011. This patent application claims benefit of the filing date under 35 USC §120 of copending U.S. provisional patent application No. 61/534,046 entitled “Compressor Intake Muffler And Filter” filed on Sep. 13, 2011. 
       INCORPORATION BY REFERENCE 
       [0002]    This patent application incorporates by reference in its entirety U.S. provisional patent application No. 61/533,993 entitled “Air Ducting Shroud For Cooling An Air Compressor Pump And Motor” filed on Sep. 13, 2011. This patent application incorporates by reference in its entirety U.S. provisional patent application No. 61/534,001 entitled “Shroud For Capturing Fan Noise” filed on Sep. 13, 2011. This patent application incorporates by reference in its entirety U.S. provisional patent application No. 61/534,009 entitled “Method Of Reducing Air Compressor Noise” filed on Sep. 13, 2011. This patent application incorporates by reference in its entirety U.S. provisional patent application No. 61/534,015 entitled “Tank Dampening Device” filed on Sep. 13, 2011. This patent application incorporates by reference in its entirety U.S. provisional patent application No. 61/534,046 entitled “Compressor Intake Muffler And Filter” filed on Sep. 13, 2011. 
     
    
     FIELD OF THE INVENTION 
       [0003]    The invention relates to a compressor for air, gas or gas mixtures. 
       BACKGROUND OF THE INVENTION 
       [0004]    Compressors are widely used in numerous applications. Existing compressors can generate a high noise output during operation. This noise can be annoying to users and can be distracting to those in the environment of compressor operation. Non-limiting examples of compressors which generate unacceptable levels of noise output include reciprocating, rotary screw and rotary centrifugal types. Compressors which are mobile or portable and not enclosed in a cabinet or compressor room can be unacceptably noisy. However, entirely encasing a compressor, for example in a cabinet or compressor room, is expensive, prevents mobility of the compressor and is often inconvenient or not feasible. Additionally, such encasement can create heat exchange and ventilation problems. There is a strong and urgent need for a quieter compressor technology. 
         [0005]    When a power source for a compressor is electric, gas or diesel, unacceptably high levels of unwanted heat and exhaust gases can be produced. Additionally, existing compressors can be inefficient in cooling a compressor pump and motor. Existing compressors can use multiple fans, e.g. a compressor can have one fan associated with a motor and a different fan associated with a pump. The use of multiple fans adds cost manufacturing difficulty, noise and unacceptable complexity to existing compressors. Current compressors can also have improper cooling gas flow paths which can choke cooling gas flows to the compressor and its components. Thus, there is a strong and urgent need for a more efficient cooling design for compressors. 
       SUMMARY OF THE INVENTION 
       [0006]    In an embodiment, the compressor assembly disclosed herein can have a tank seal which seals a tank gap between a portion of a housing of the compressor assembly and a portion of a compressed gas tank; and a sound level of the compressor assembly which is in a range of from 65 dBA to 75 dBA when the compressor assembly is in a compressing state. 
         [0007]    The compressor assembly can have a difference in sound level between a location at a pump assembly side of the tank seal and the outside of the tank seal is in a range of from about 2 dBA to about 10 dBA. The compressor assembly can have a difference in sound level between a location at a pump assembly side of the tank seal and the outside of the tank seal is in a range of from about 2 dBA to about 8 dBA. The compressor assembly can have a difference in sound level between a location at a pump assembly side of the tank seal and the outside of the tank seal is in a range of from about 2.5 dBA to about 5 dBA. The compressor assembly can have a difference in sound level between a location at a pump assembly side of the tank seal and the outside of the tank seal is in a range of from about 5 dBA to about 8 dBA. The compressor assembly can have a difference in sound level between a location at a pump assembly side of the tank seal and the outside of the tank seal is about 2.5 dBA. The compressor assembly can have a difference in sound level between a location at a pump assembly side of the tank seal and the outside of the tank seal is about 5.0 dBA. The compressor assembly can have a difference in sound level between a location at a pump assembly side of the tank seal and the outside of the tank seal is about 8.0 dBA. 
         [0008]    The compressor assembly can have a tank seal having a seal bulb. The compressor assembly can have a tank seal having a housing seal. The compressor assembly can have a tank seal having a seal hook. The compressor assembly can have a tank seal having a seal rib. The compressor assembly can have a tank seal having seal bulb which can be compressed. 
         [0009]    In an aspect, the compressor assembly disclose herein can control the sound level of the compressor assembly by a method having the steps of: providing a compressor assembly having a housing; providing a compressed gas tank; configuring the housing and compressed gas tank to have tank gap between the housing and the compressed gas tank; providing a tank seal; and sealing the tank gap with the tank seal. 
         [0010]    The method for controlling having the step of operating the compressor assembly in a compressing state at a sound level in a range of between 65 dBA and 75 dBA. The method for controlling the sound level of a compressor assembly having the steps of operating the compressor assembly in a compressing state at a sound level in a range of between 65 dBA and 75 dBA, and compressing 2.4 SCFM to 3.5 SCFM of gas. 
         [0011]    The method for controlling the sound level of a compressor assembly according to claim  13 , further having the steps of operating the compressor assembly in a compressing state at a sound level in a range of between 65 dBA and 75 dBA, and compressing gas to a pressure of 50 PSIG to 250 PSIG. 
         [0012]    The method for controlling the sound level of a compressor assembly can have the step of transferring heat from a pump assembly at a rate of from 60 BTU/min to 200 BTU/min. 
         [0013]    In an aspect, the compressor assembly disclosed herein can have a means for controlling the sound level of a compressor assembly, which uses a means to seal a tank gap between at least a portion of a housing and at least a portion of a compressed gas tank and by operating the compressor assembly in a range of from 65 dBA to 75 dBA when the compressor assembly is in a compressing state. The compressor assembly can have a means for controlling the sound level of a compressor assembly, wherein a means to seal a tank gap is used which has a deformable portion. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0014]    The present invention in its several aspects and embodiments solves the problems discussed above and significantly advances the technology of compressors. The present invention can become more fully understood from the detailed description and the accompanying drawings, wherein: 
           [0015]      FIG. 1  is a perspective view of a compressor assembly; 
           [0016]      FIG. 2  is a front view of internal components of the compressor assembly; 
           [0017]      FIG. 3  is a front sectional view of the motor and fan assembly; 
           [0018]      FIG. 4  is a pump-side view of components of the pump assembly; 
           [0019]      FIG. 5  is a fan-side perspective of the compressor assembly; 
           [0020]      FIG. 6  is a rear perspective of the compressor assembly; 
           [0021]      FIG. 7  is a rear view of internal components of the compressor assembly; 
           [0022]      FIG. 8  is a rear sectional view of the compressor assembly; 
           [0023]      FIG. 9  is a top view of components of the pump assembly; 
           [0024]      FIG. 10  is a top sectional view of the pump assembly; 
           [0025]      FIG. 11  is an exploded view of the air ducting shroud; 
           [0026]      FIG. 12  is a rear view of a valve plate assembly; 
           [0027]      FIG. 13  is a cross-sectional view of the valve plate assembly; 
           [0028]      FIG. 14  is a front view of the valve plate assembly; 
           [0029]      FIG. 15A  is a perspective view of sound control chambers of the compressor assembly; 
           [0030]      FIG. 15B  is a perspective view of sound control chambers having optional sound absorbers; 
           [0031]      FIG. 16A  is a perspective view of sound control chambers with an air ducting shroud; 
           [0032]      FIG. 16B  is a perspective view of sound control chambers having optional sound absorbers; 
           [0033]      FIG. 17  is a first table of embodiments of compressor assembly ranges of performance characteristics; 
           [0034]      FIG. 18  is a second table of embodiments of compressor assembly ranges of performance characteristics; 
           [0035]      FIG. 19  is a first table of example performance characteristics for an example compressor assembly; 
           [0036]      FIG. 20  is a second table of example performance characteristics for an example compressor assembly; 
           [0037]      FIG. 21  is a table containing a third example of performance characteristics of an example compressor assembly; 
           [0038]      FIG. 22  is a perspective view of a pump assembly and compressed gas tank having a tank gap; 
           [0039]      FIG. 23  is a fan-side view of a pump assembly and compressed gas tank having a tank gap; 
           [0040]      FIG. 24  is a perspective view of a pump assembly and compressed gas tank having a tank seal; 
           [0041]      FIG. 25  is a detail of the tank seal of  FIG. 24 ; 
           [0042]      FIG. 26  is a fan-side view of a pump assembly and compressed gas tank having a tank seal; 
           [0043]      FIG. 27  is a fan-side sectional view of a pump assembly and compressed gas tank having a tank seal; 
           [0044]      FIG. 28A  is a detail of a tank seal; 
           [0045]      FIG. 28B  is a cross-sectional view of a tank seal; 
           [0046]      FIG. 28C  is a side view of a tank seal; 
           [0047]      FIG. 29  is a pump-side view of a pump assembly and compressed gas tank having a tank seal; 
           [0048]      FIG. 30  is an exploded front perspective view of a pump assembly and compressed gas tank having a tank seal; 
           [0049]      FIG. 31  is an exploded rear perspective view of a pump assembly and compressed gas tank having a tank seal; 
           [0050]      FIG. 32  is an embodiment of a tank seal; 
           [0051]      FIG. 33  is a view having piece of a tank seal which is detached; and 
           [0052]      FIG. 34  illustrates an embodiment of a tank seal made of foam. 
       
    
    
       [0053]    Herein, like reference numbers in one figure refer to like reference numbers in another figure. 
       DETAILED DESCRIPTION OF THE INVENTION 
       [0054]    The invention relates to a compressor assembly which can compress air, or gas, or gas mixtures, and which has a low noise output, effective cooling means and high heat transfer. The inventive compressor assembly achieves efficient cooling of the compressor assembly  20  ( FIG. 1 ) and/or pump assembly  25  ( FIG. 2 ) and/or the components thereof ( FIGS. 3 and 4 ). In an embodiment, the compressor can compress air. In another embodiment, the compressor can compress one or more gases, inert gases, or mixed gas compositions. The disclosure herein regarding compression of air is also applicable to the use of the disclosed apparatus in its many embodiments and aspects in a broad variety of services and can be used to compress a broad variety of gases and gas mixtures. 
         [0055]      FIG. 1  is a perspective view of a compressor assembly  20  shown according to the invention. In an embodiment, the compressor assembly  20  can compress air, or can compress one or more gases, or gas mixtures. In an embodiment, the compressor assembly  20  is also referred to hearing herein as “a gas compressor assembly” or “an air compressor assembly”. 
         [0056]    The compressor assembly  20  can optionally be portable. The compressor assembly  20  can optionally have a handle  29 , which optionally can be a portion of frame  10 . 
         [0057]    In an embodiment, the compressor assembly  20  can have a value of weight between 15 lbs and 100 lbs. In an embodiment, the compressor assembly  20  can be portable and can have a value of weight between 15 lbs and 50 lbs. In an embodiment, the compressor assembly  20  can have a value of weight between 25 lbs and 40 lbs. In an embodiment, the compressor assembly  20  can have a value of weight of, e.g. 38 lbs, or 29 lbs, or 27 lbs, or 25 lbs, or 20 lbs, or less. In an embodiment, frame  10  can have a value of weight of 10 lbs or less. In an embodiment, frame  10  can weigh 5 lbs, or less, e.g. 4 lbs, or 3 lbs, of 2 lbs, or less. 
         [0058]    In an embodiment, the compressor assembly  20  can have a front side  12  (“front”), a rear side  13  (“rear”), a fan side  14  (“fan-side”), a pump side  15  (“pump-side”), a top side  16  (“top”) and a bottom side  17  (“bottom”). 
         [0059]    The compressor assembly  20  can have a housing  21  which can have ends and portions which are referenced herein by orientation consistently with the descriptions set forth above. In an embodiment, the housing  21  can have a front housing  160 , a rear housing  170 , a fan-side housing  180  and a pump-side housing  190 . The front housing  160  can have a front housing portion  161 , a top front housing portion  162  and a bottom front housing potion  163 . The rear housing  170  can have a rear housing portion  171 , a top rear housing portion  172  and a bottom rear housing portion  173 . The fan-side housing  180  can have a fan cover  181  and a plurality of intake ports  182 . The compressor assembly can be cooled by air flow provided by a fan  200  ( FIG. 3 ), e.g. cooling air stream  2000  ( FIG. 3 ). 
         [0060]    In an embodiment, the housing  21  can be compact and can be molded. The housing  21  can have a construction at least in part of plastic, or polypropylene, acrylonitrile butadiene styrene (ABS), metal, steel, stamped steel, fiberglass, thermoset plastic, cured resin, carbon fiber, or other material. The frame  10  can be made of metal, steel, aluminum, carbon fiber, plastic or fiberglass. 
         [0061]    Power can be supplied to the motor of the compressor assembly through a power cord  5  extending through the fan-side housing  180 . In an embodiment, the compressor assembly  20  can comprise one or more of a cord holder member, e.g. first cord wrap  6  and second cord wrap  7  ( FIG. 2 ). 
         [0062]    In an embodiment, power switch  11  can be used to change the operating state of the compressor assembly  20  at least from an “on” to an “off” state, and vice versa. In an “on” state, the compressor can be in a compressing state (also herein as a “pumping state”) in which it is compressing air, or a gas, or a plurality of gases, or a gas mixture. 
         [0063]    In an embodiment, other operating modes can be engaged by power switch  11  or a compressor control system, e.g. a standby mode, or a power save mode. In an embodiment, the front housing  160  can have a dashboard  300  which provides an operator-accessible location for connections, gauges and valves which can be connected to a manifold  303  ( FIG. 7 ). In an embodiment, the dashboard  300  can provide an operator access in non-limiting example to a first quick connection  305 , a second quick connection  310 , a regulated pressure gauge  315 , a pressure regulator  320  and a tank pressure gauge  325 . In an embodiment, a compressed gas outlet line, hose or other device to receive compressed gas can be connected the first quick connection  305  and/or second quick connection  310 . In an embodiment, as shown in  FIG. 1 , the frame can be configured to provide an amount of protection to the dashboard  300  from the impact of objects from at least the pump-side, fan-side and top directions. 
         [0064]    In an embodiment, the pressure regulator  320  employs a pressure regulating valve. The pressure regulator  320  can be used to adjust the pressure regulating valve  26  ( FIG. 7 ). The pressure regulating valve  26  can be set to establish a desired output pressure. In an embodiment, excess air pressure can be can vented to atmosphere through the pressure regulating valve  26  and/or pressure relief valve  199  ( FIG. 1 ). In an embodiment, pressure relief valve  199  can be a spring loaded safety valve. In an embodiment, the air compressor assembly  20  can be designed to provide an unregulated compressed air output. 
         [0065]    In an embodiment, the pump assembly  25  and the compressed gas tank  150  can be connected to frame  10 . The pump assembly  25 , housing  21  and compressed gas tank  150  can be connected to the frame  10  by a plurality of screws and/or one or a plurality of welds and/or a plurality of connectors and/or fasteners. 
         [0066]    The plurality of intake ports  182  can be formed in the housing  21  adjacent the housing inlet end  23  and a plurality of exhaust ports  31  can be formed in the housing  21 . In an embodiment, the plurality of the exhaust ports  31  can be placed in housing  21  in the front housing portion  161 . Optionally, the exhaust ports  31  can be located adjacent to the pump end of housing  21  and/or the pump assembly  25  and/or the pump cylinder  60  and/or cylinder head  61  ( FIG. 2 ) of the pump assembly  25 . In an embodiment, the exhaust ports  31  can be provided in a portion of the front housing portion  161  and in a portion of the bottom front housing portion  163 . 
         [0067]    The total cross-sectional open area of the intake ports  182  (the sum of the cross-sectional areas of the individual intake ports  182 ) can be a value in a range of from 3.0 in̂2 to 100 in̂2. In an embodiment, the total cross-sectional open area of the intake ports  182  can be a value in a range of from 6.0 in̂2 to 38.81 in̂2. In an embodiment, the total cross-sectional open area of the intake ports  182  can be a value in a range of from 9.8 in̂2 to 25.87 in̂2. In an embodiment, the total cross-sectional open area of the intake ports  182  can be 12.936 in̂2. 
         [0068]    In an embodiment, the cooling gas employed to cool compressor assembly  20  and its components can be air (also known herein as “cooling air”). The cooling air can be taken in from the environment in which the compressor assembly  20  is placed. The cooling air can be ambient from the natural environment, or air which has been conditioned or treated. The definition of “air” herein is intended to be very broad. The term “air” includes breathable air, ambient air, treated air, conditioned air, clean room air, cooled air, heated air, non-flammable oxygen containing gas, filtered air, purified air, contaminated air, air with particulates solids or water, air from bone dry (i.e. 0.00 humidity) air to air which is supersaturated with water, as well as any other type of air present in an environment in which a gas (e.g. air) compressor can be used. It is intended that cooling gases which are not air are encompassed by this disclosure. For non-limiting example, a cooling gas can be nitrogen, can comprise a gas mixture, can comprise nitrogen, can comprise oxygen (in a safe concentration), can comprise carbon dioxide, can comprise one inert gas or a plurality of inert gases, or comprise a mixture of gases. 
         [0069]    In an embodiment, cooling air can be exhausted from compressor assembly  20  through a plurality of exhaust ports  31 . The total cross-sectional open area of the exhaust ports  31  (the sum of the cross-sectional areas of the individual exhaust ports  31 ) can be a value in a range of from 3.0 in̂2 to 100 in̂2. In an embodiment, the total cross-sectional open area of the exhaust ports can be a value in a range of from 3.0 in̂2 to 77.62 in̂2. In an embodiment, the total cross-sectional open area of the exhaust ports can be a value in a range of from 4.0 in̂2 to 38.81 in̂2. In an embodiment, the total cross-sectional open area of the exhaust ports can be a value in a range of from 4.91 in̂2 to 25.87 in̂2. In an embodiment, the total cross-sectional open area of the exhaust ports can be 7.238 in̂2. 
         [0070]    Numeric values and ranges herein, unless otherwise stated, also are intended to have associated with them a tolerance and to account for variances of design and manufacturing, and/or operational and performance fluctuations. Thus, a number disclosed herein is intended to disclose values “about” that number. For example, a value X is also intended to be understood as “about X”. Likewise, a range of Y-Z is also intended to be understood as within a range of from “about Y-about Z”. Unless otherwise stated, significant digits disclosed for a number are not intended to make the number an exact limiting value. Variance and tolerance, as well as operational or performance fluctuations, are an expected aspect of mechanical design and the numbers disclosed herein are intended to be construed to allow for such factors (in non-limiting e.g., ±10 percent of a given value). This disclosure is to be broadly construed. Likewise, the claims are to be broadly construed in their recitations of numbers and ranges. 
         [0071]    The compressed gas tank  150  can operate at a value of pressure in a range of at least from ambient pressure, e.g. 14.7 psig to 3000 psig (“psig” is the unit lbf/in̂2 gauge), or greater. In an embodiment, compressed gas tank  150  can operate at 200 psig. In an embodiment, compressed gas tank  150  can operate at 150 psig. 
         [0072]    In an embodiment, the compressor has a pressure regulated on/off switch which can stop the pump when a set pressure is obtained. In an embodiment, the pump is activated when the pressure of the compressed gas tank  150  falls to 70 percent of the set operating pressure, e.g. to activate at 140 psig with an operating set pressure of 200 psig (140 psig=0.70*200 psig). In an embodiment, the pump is activated when the pressure of the compressed gas tank  150  falls to 80 percent of the set operating pressure, e.g. to activate at 160 psig with an operating set pressure of 200 psig (160 psig=0.80*200 psig). Activation of the pump can occur at a value of pressure in a wide range of set operating pressure, e.g. 25 percent to 99.5 percent of set operating pressure. Set operating pressure can also be a value in a wide range of pressure, e.g. a value in a range of from 25 psig to 3000 psig. An embodiment of set pressure can be 50 psig, 75 psig, 100 psig, 150 psig, 200 psig, 250 psig, 300 psig, 500 psig, 1000 psig, 2000 psig, 3000 psig, or greater than or less than, or a value in between these example numbers. 
         [0073]    The compressor assembly  20  disclosed herein in its various embodiments achieves a reduction in the noise created by the vibration of the air tank while the air compressor is running, in its compressing state (pumping state) e.g. to a value in a range of from 60-75 dBA, or less, as measured by ISO3744-1995. Noise values discussed herein are compliant with ISO3744-1995. ISO3744-1995 is the standard for noise data and results for noise data, or sound data, provided in this application. Herein “noise” and “sound” are used synonymously. 
         [0074]    The pump assembly  25  can be mounted to an air tank and can be covered with a housing  21 . A plurality of optional decorative shapes  141  can be formed on the front housing portion  161 . The plurality of optional decorative shapes  141  can also be sound absorbing and/or vibration dampening shapes. The plurality of optional decorative shapes  141  can optionally be used with, or contain at least in part, a sound absorbing material. 
         [0075]      FIG. 2  is a front view of internal components of the compressor assembly. 
         [0076]    The compressor assembly  20  can include a pump assembly  25 . In an embodiment, pump assembly  25  which can compress a gas, air or gas mixture. In an embodiment in which the pump assembly  25  compresses air, it is also referred to herein as air compressor  25 , or compressor  25 . In an embodiment, the pump assembly  25  can be powered by a motor  33  (e.g.  FIG. 3 ). 
         [0077]      FIG. 2  illustrates the compressor assembly  20  with a portion of the housing  21  removed and showing the pump assembly  25 . In an embodiment, the fan-side housing  180  can have a fan cover  181  and a plurality of intake ports  182 . The cooling gas, for example air, can be fed through an air inlet space  184  which feeds air into the fan  200  (e.g.  FIG. 3 ). In an embodiment, the fan  200  can be housed proximate to an air intake port  186  of an air ducting shroud  485 . 
         [0078]    Air ducting shroud  485  can have a shroud inlet scoop  484 . As illustrated in  FIG. 2 , air ducting shroud  485  is shown encasing the fan  200  and the motor  33  ( FIG. 3 ). In an embodiment, the shroud inlet scoop  484  can encase the fan  200 , or at least a portion of the fan and at least a portion of motor  33 . In this embodiment, an air inlet space  184  which feeds air into the fan  200  is shown. The air ducting shroud  485  can encase the fan  200  and the motor  33 , or at least a portion of these components. 
         [0079]      FIG. 2  is an intake muffler  900  which can receive feed air for compression (also herein as “feed air  990 ”; e.g.  FIG. 8 ) via the intake muffler feed line  898 . The feed air  990  can pass through the intake muffler  900  and be fed to the cylinder head  61  via the muffler outlet line  902 . The feed air  990  can be compressed in pump cylinder  60  by piston  63 . The piston can be provided with a seal which can function, such as slide, in the cylinder without liquid lubrication. The cylinder head  61  can be shaped to define an inlet chamber  81  (e.g.  FIG. 9 ) and an outlet chamber  82  (e.g.  FIG. 8 ) for a compressed gas, such as air (also known herein as “compressed air  999 ” or “compressed gas  999 ”; e.g.  FIG. 10 ). In an embodiment, the pump cylinder  60  can be used as at least a portion of an inlet chamber  81 . A gasket can form an air tight seal between the cylinder head  61  and the valve plate assembly  62  to prevent a leakage of a high pressure gas, such as compressed air  999 , from the outlet chamber  82 . Compressed air  999  can exit the cylinder head  61  via a compressed gas outlet port  782  and can pass through a compressed gas outlet line  145  to enter the compressed gas tank  150 . 
         [0080]    As shown in  FIG. 2 , the pump assembly  25  can have a pump cylinder  60 , a cylinder head  61 , a valve plate assembly  62  mounted between the pump cylinder  60  and the cylinder head  61 , and a piston  63  which is reciprocated in the pump cylinder  60  by an eccentric drive  64  (e.g.  FIG. 9 ). The eccentric drive  64  can include a sprocket  49  which can drive a drive belt  65  which can drive a pulley  66 . A bearing  67  can be eccentrically secured to the pulley  66  by a screw, or a rod bolt  57 , and a connecting rod  69 . Preferably, the sprocket  49  and the pulley  66  can be spaced around their perimeters and the drive belt  65  can be a timing belt. The pulley  66  can be mounted about pulley centerline  887  and linked to a sprocket  49  by the drive belt  65  ( FIG. 3 ) which can be configured on an axis which is represent herein as a shaft centerline  886  supported by a bracket and by a bearing  47  ( FIG. 3 ). A bearing can allow the pulley  66  to be rotated about an axis  887  ( FIG. 10 ) when the motor rotates the sprocket  49 . As the pulley  66  rotates about the axis  887  ( FIG. 10 ), the bearing  67  ( FIG. 2 ) and an attached end of the connecting rod  69  are moved around a circular path. 
         [0081]    The piston  63  can be formed as an integral part of the connecting rod  69 . A compression seal can be attached to the piston  63  by a retaining ring and a screw. In an embodiment, the compression seal can be a sliding compression seal. 
         [0082]    A cooling gas stream, such as cooling air stream  2000  ( FIG. 3 ), can be drawn through intake ports  182  to feed fan  200 . The cooling air stream  2000  can be divided into a number of different cooling air stream flows which can pass through portions of the compressor assembly and exit separately, or collectively as an exhaust air steam through the plurality of exhaust ports  31 . Additionally, the cooling gas, e.g. cooling air stream  2000 , can be drawn through the plurality of intake ports  182  and directed to cool the internal components of the compressor assembly  20  in a predetermined sequence to optimize the efficiency and operating life of the compressor assembly  20 . The cooling air can be heated by heat transfer from compressor assembly  20  and/or the components thereof, e.g. pump assembly  25  ( FIG. 3 ). The heated air can be exhausted through the plurality of exhaust ports  31 . 
         [0083]    In an embodiment, one fan can be used to cool both the pump and motor. A design using a single fan to provide cooling to both the pump and motor can require less air flow than a design using two or more fans, e.g. using one or more fans to cool the pump, and also using one or more fans to cool the motor. Using a single fan to provide cooling to both the pump and motor can reduce power requirements and also reduces noise production as compared to designs using a plurality of fans to cool the pump and the motor, or which use a plurality of fans to cool the pump assembly  25 , or the compressor assembly  20 . 
         [0084]    In an embodiment, the fan blade  205  (e.g.  FIG. 3 ) establishes a forced flow of cooling air through the internal housing, such as the air ducting shroud  485 . The cooling air flow through the air ducting shroud can be a volumetric flow rate having a value of between 25 CFM to 400 CFM. The cooling air flow through the air ducting shroud can be a volumetric flow rate having a value of between 45 CFM to 125 CFM. 
         [0085]    In an embodiment, the outlet pressure of cooling air from the fan can be in a range of from 1 psig to 50 psig. In an embodiment, the fan  200  can be a low flow fan with which generates an outlet pressure having a value in a range of from 1 in of water to 10 psi. In an embodiment, the fan  200  can be a low flow fan with which generates an outlet pressure having a value in a range of from 2 in of water to 5 psi. 
         [0086]    In an embodiment, the air ducting shroud  485  can flow 100 CFM of cooling air with a pressure drop of from 0.0002 psi to 50 psi along the length of the air ducting shroud. In an embodiment, the air ducting shroud  485  can flow 75 CFM of cooling air with a pressure drop of 0.028 psi along its length as measured from the entrance to fan  200  through the exit from conduit  253  ( FIG. 7 ). 
         [0087]    In an embodiment, the air ducting shroud  485  can flow 75 CFM of cooling air with a pressure drop of 0.1 psi along its length as measured from the outlet of fan  200  through the exit from conduit  253 . In an embodiment, the air ducting shroud  485  can flow 100 CFM of cooling air with a pressure drop of 1.5 psi along its length as measured from the outlet of fan  200  through the exit from conduit  253 . In an embodiment, the air ducting shroud  485  can flow 150 CFM of cooling air with a pressure drop of 5.0 psi along its length as measured from the outlet of fan  200  through the exit from conduit  253 . 
         [0088]    In an embodiment, the air ducting shroud  485  can flow 75 CFM of cooling air with a pressure drop in a range of from 1.0 psi to 30 psi across as measured from the outlet of fan  200  across the motor  33 . 
         [0089]    Depending upon the compressed gas (e.g. compressed air  999 ) output, the design rating of the motor  33  and the operating voltage, in an embodiment the motor  33  can operate at a value of rotation (motor speed) between 5,000 rpm and 20,000 rpm. In an embodiment, the motor  33  can operate at a value in a range of between 7,500 rpm and 12,000 rpm. In an embodiment, the motor  33  can operate at e.g. 11,252 rpm, or 11,000 rpm; or 10,000 rpm; or 9,000 rpm; or 7,500; or 6,000 rpm; or 5,000 rpm. The pulley  66  and the sprocket  49  can be sized to achieve reduced pump speeds (also herein as “reciprocation rates”, or “piston speed”) at which the piston  63  is reciprocated. For example, if the sprocket  49  can have a diameter of 1 in and the pulley  66  can have a diameter of 4 in, then a motor  33  speed of 14,000 rpm can achieve a reciprocation rate, or a piston speed, of 3,500 strokes per minute. In an embodiment, if the sprocket  49  can have a diameter of 1.053 in and the pulley  66  can have a diameter of 5.151 in, then a motor  33  speed of 11,252 rpm can achieve a reciprocation rate, or a piston speed (pump speed), of 2,300 strokes per minute. 
         [0090]      FIG. 3  is a front sectional view of the motor and fan assembly. 
         [0091]      FIG. 3  illustrates the fan  200  and motor  33  covered by air ducting shroud  485 . The fan  200  is shown proximate to a shroud inlet scoop  484 . 
         [0092]    The motor can have a stator  37  with an upper pole  38  around which upper stator coil  40  is wound and/or configured. The motor can have a stator  37  with a lower pole  39  around which lower stator coil  41  is wound and/or configured. A shaft  43  can be supported adjacent a first shaft end  44  by a bearing  45  and is supported adjacent to a second shaft end  46  by a bearing  47 . A plurality of fan blades  205  can be secured to the fan  200  which can be secured to the first shaft end  44 . When power is applied to the motor  33 , the shaft  43  rotates at a high speed to in turn drive the sprocket  49  ( FIG. 2 ), the drive belt  65  ( FIG. 4 ), the pulley  66  ( FIG. 4 ) and the fan blade  200 . In an embodiment, the motor can be a non-synchronous universal motor. In an embodiment, the motor can be a synchronous motor used. 
         [0093]    The compressor assembly  20  can be designed to accommodate a variety of types of motor  33 . The motors  33  can come from different manufacturers and can have horsepower ratings of a value in a wide range from small to very high. In an embodiment, a motor  33  can be purchased from the existing market of commercial motors. For example, although the housing  21  is compact, in an embodiment it can accommodate a universal motor, or other motor type, rated, for example, at ½ horsepower, at ¾ horsepower or 1 horsepower by scaling and/or designing the air ducting shroud  485  to accommodate motors in a range from small to very large. 
         [0094]      FIG. 3  and  FIG. 4  illustrate the compression system for the compressor which is also referred to herein as the pump assembly  25 . The pump assembly  25  can have a pump  59 , a pulley  66 , drive belt  65  and driving mechanism driven by motor  33 . The connecting rod  69  can connect to a piston  63  (e.g.  FIG. 10 ) which can move inside of the pump cylinder  60 . 
         [0095]    In one embodiment, the pump  59  such as “gas pump” or “air pump” can have a piston  63 , a pump cylinder  60 , in which a piston  63  reciprocates and a cylinder rod  69  ( FIG. 2 ) which can optionally be oil-less and which can be driven to compress a gas, e.g. air. The pump  59  can be driven by a high speed universal motor, e.g. motor  33  ( FIG. 3 ), or other type of motor. 
         [0096]      FIG. 4  is a pump-side view of components of the pump assembly  25 . The “pump assembly  25 ” can have the components which are attached to the motor and/or which serve to compress a gas; which in non-limiting example can comprise the fan, the motor  33 , the pump cylinder  60  and piston  63  (and its driving parts), the valve plate assembly  62 , the cylinder head  61  and the outlet of the cylinder head  782 . Herein, the feed air system  905  system ( FIG. 7 ) is referred to separately from the pump assembly  25 . 
         [0097]      FIG. 4  illustrates that pulley  66  is driven by the motor  33  using drive belt  65 . 
         [0098]      FIG. 4  (also see  FIG. 10 ) illustrates an offset  880  which has a value of distance which represents one half (½) of the stroke distance. The offset  880  can have a value between 0.25 in and 6 in, or larger. In an embodiment, the offset  880  can have a value between 0.75 in and 3 in. In an embodiment, the offset  880  can have a value between 1.0 in and 2 in, e.g. 1.25 in. In an embodiment, the offset  880  can have a value of about 0.796 in. In an embodiment, the offset  880  can have a value of about 0.5 in. In an embodiment, the offset  880  can have a value of about 1.5 in. 
         [0099]    A stroke having a value in a range of from 0.50 in and 12 in, or larger can be used. A stroke having a value in a range of from 1.5 in and 6 in can be used. A stroke having a value in a range of from 2 in and 4 in can be used. A stroke of 2.5 in can be used. In an embodiment, the stroke can be calculated to equal two (2) times the offset, for example, an offset  880  of 0.796 produces a stroke of 2(0.796)=1.592 in. In another example, an offset  880  of 2.25 produces a stroke of 2(2.25)=4.5 in. In yet another example, an offset  880  of 0.5 produces a stroke of 2(0.5)=1.0 in. 
         [0100]    The compressed air passes through valve plate assembly  62  and into the cylinder head  61  having a plurality of cooling fins  89 . The compressed gas, is discharged from the cylinder head  61  through the outlet line  145  which feeds compressed gas to the compressed gas tank  150 . 
         [0101]      FIG. 4  also identifies the pump-side of upper motor path  268  which can provide cooling air to upper stator coil  40  and lower motor path  278  which can provide cooling to lower stator coil  41 . 
         [0102]      FIG. 5  illustrates tank seal  600  providing a seal between the housing  21  and compressed gas tank  150  viewed from fan-side  14 .  FIG. 5  is a fan-side perspective of the compressor assembly  20 .  FIG. 5  illustrates a fan-side housing  180  having a fan cover  181  with intake ports  182 .  FIG. 5  also shows a fan-side view of the compressed gas tank  150 . Tank seal  600  is illustrated sealing the housing  21  to the compressed gas tank  150 . Tank seal  600  can be a one piece member or can have a plurality of segments which form tank seal  600 . 
         [0103]      FIG. 6  is a rear-side perspective of the compressor assembly  20 .  FIG. 6  illustrates a tank seal  600  sealing the housing  21  to the compressed gas tank  150 . 
         [0104]      FIG. 7  is a rear view of internal components of the compressor assembly. In this sectional view, in which the rear housing  170  is not shown, the fan-side housing  180  has a fan cover  181  and intake ports  182 . The fan-side housing  180  is configured to feed air to air ducting shroud  485 . Air ducting shroud  485  has shroud inlet scoop  484  and conduit  253  which can feed a cooling gas, such as air, to the cylinder head  61  and pump cylinder  60 . 
         [0105]      FIG. 7  also provides a view of the feed air system  905 . The feed air system  905  can feed a feed air  990  through a feed air port  952  for compression in the pump cylinder  60  of pump assembly  25 . The feed air port  952  can optionally receive a clean air feed from an inertia filter  949  ( FIG. 8 ). The clean air feed can pass through the feed air port  952  to flow through an air intake hose  953  and an intake muffler feed line  898  to the intake muffler  900 . The clean air can flow from the intake muffler  900  through muffler outlet line  902  and cylinder head hose  903  to feed pump cylinder head  61 . Noise can be generated by the compressor pump, such as when the piston forces air in and out of the valves of valve plate assembly  62 . The intake side of the pump can provide a path for the noise to escape from the compressor which intake muffler  900  can serve to muffle. 
         [0106]    The filter distance  1952  between an inlet centerline  1950  of the feed air port  952  and a scoop inlet  1954  of shroud inlet scoop  484  can vary widely and have a value in a range of from 0.5 in to 24 in, or even greater for larger compressor assemblies. The filter distance  1952  between inlet centerline  1950  and inlet cross-section of shroud inlet scoop  484  identified as scoop inlet  1954  can be e.g. 0.5 in, or 1.0 in, or 1.5 in, or 2.0 in, or 2.5 in, or 3.0 in, or 4.0 in, or 5.0 in or 6.0 in, or greater. In an embodiment, the filter distance  1952  between inlet centerline  1950  and inlet cross-section of shroud inlet scoop  484  identified as scoop inlet  1954  can be 1.859 in. In an embodiment, the inertia filter can have multiple inlet ports which can be located at different locations of the air ducting shroud  485 . In an embodiment, the inertial filter is separate from the air ducting shroud and its feed is derived from one or more inlet ports. 
         [0107]      FIG. 7  illustrates that compressed air can exit the cylinder head  61  via the compressed gas outlet port  782  and pass through the compressed gas outlet line  145  to enter the compressed gas tank  150 .  FIG. 7  also shows a rear-side view of manifold  303 . 
         [0108]      FIG. 8  is a rear sectional view of the compressor assembly  20 .  FIG. 8  illustrates the fan cover  181  having a plurality of intake ports  182 . A portion of the fan cover  181  can be extended toward the shroud inlet scoop  484 , e.g. the rim  187 . In this embodiment, the fan cover  181  has a rim  187  which can eliminate a visible line of sight to the air inlet space  184  from outside of the housing  21 . In an embodiment, the rim  187  can cover or overlap an air space  188 .  FIG. 8  illustrates an inertia filter  949  having an inertia filter chamber  950  and air intake path  922 . 
         [0109]    In an embodiment, the rim  187  can extend past the air inlet space  184  and overlaps at least a portion of the shroud inlet scoop  484 . In an embodiment, the rim  187  does not extend past and does not overlap a portion of the shroud inlet scoop  484  and the air inlet space  184  can have a width between the rim  187  and a portion of the shroud inlet scoop  484  having a value of distance in a range of from 0.1 in to 2 in, e.g. 0.25 in, or 0.5 in. In an embodiment, the air ducting shroud  485  and/or the shroud inlet scoop  484  can be used to block line of sight to the fan  200  and the pump assembly  25  in conjunction with or instead of the rim  187 . 
         [0110]    The inertia filter  949  can provide advantages over the use of a filter media which can become plugged with dirt and/or particles and which can require replacement to prevent degrading of compressor performance. Additionally, filter media, even when it is new, creates a pressure drop and can reduce compressor performance. 
         [0111]    Air must make a substantial change in direction from the flow of cooling air to become compressed gas feed air to enter and pass through the feed air port  952  to enter the air intake path  922  from the inertia filter chamber  950  of the inertia filter  949 . Any dust and other particles dispersed in the flow of cooling air have sufficient inertia that they tend to continue moving with the cooling air rather than change direction and enter the air intake path  922 . 
         [0112]      FIG. 8  also shows a section of a dampening ring  700 . The dampening ring  700  can optionally have a cushion member  750 , as well as optionally a first hook  710  and a second hook  720 . 
         [0113]      FIG. 9  is a top view of the components of the pump assembly  25 . 
         [0114]    Pump assembly  25  can have a motor  33  which can drive the shaft  43  which causes a sprocket  49  to drive a drive belt  65  to rotate a pulley  66 . The pulley  66  can be connected to and can drive the connecting rod  69  which has a piston  63  ( FIG. 2 ) at an end. The piston  63  can compress a gas in the pump cylinder  60  pumping the compressed gas through the valve plate assembly  62  into the cylinder head  61  and then out through a compressed gas outlet port  782  through an outlet line  145  and into the compressed gas tank  150 . 
         [0115]      FIG. 9  also shows a pump  91 . Herein, pump  91  collectively refers to a combination of parts including the cylinder head  61 , the pump cylinder  60 , the piston  63  and the connecting rod having the piston  63 , as well as the components of these parts. 
         [0116]      FIG. 10  is a top sectional view of the pump assembly  25 .  FIG. 10  also shows a shaft centerline  886 , as well as pulley centerline  887  and a rod bolt centerline  889  of a rod bolt  57 .  FIG. 10  illustrates an offset  880  which can be a dimension having a value in the range of 0.5 in to 12 in, or greater. In an embodiment, the stroke can be 1.592 in, from an offset  880  of 0.796 in.  FIG. 10  also shows air inlet chamber  81 . 
         [0117]      FIG. 11  illustrates an exploded view of the air ducting shroud  485 . In an embodiment, the air ducting shroud  485  can have an upper ducting shroud  481  and a lower ducting shroud  482 . In the example of  FIG. 11 , the upper ducting shroud  481  and the lower ducting shroud  482  can be fit together to shroud the fan  200  and the motor  33  and can create air ducts for cooling pump assembly  25  and/or the compressor assembly  20 . In an embodiment, the air ducting shroud  485  can also be a motor cover for motor  33 . The upper air ducting shroud  481  and the lower air ducting shroud  482  can be connected by a broad variety of means which can include snaps and/or screws. 
         [0118]      FIG. 12  is a rear-side view of a valve plate assembly. A valve plate assembly  62  is shown in detail in  FIGS. 12 ,  13  and  14 . 
         [0119]    The valve plate assembly  62  of the pump assembly  25  can include air intake and air exhaust valves. The valves can be of a reed, flapper, one-way or other type. A restrictor can be attached to the valve plate adjacent the intake valve. Deflection of the exhaust valve can be restricted by the shape of the cylinder head which can minimize valve impact vibrations and corresponding valve stress. 
         [0120]    The valve plate assembly  62  has a plurality of intake ports  103  (five shown) which can be closed by the intake valves  96  ( FIG. 14 ) which can extend from fingers  105  ( FIG. 13 ). In an embodiment, the intake valves  96  can be of the reed or “flapper” type and are formed, for example, from a thin sheet of resilient stainless steel. Radial fingers  113  ( FIG. 12 ) can radiate from a valve finger hub  114  to connect the plurality of valve members  104  of intake valves  96  and to function as return springs. A rivet  107  secures the hub  106  (e.g.  FIG. 13 ) to the center of the valve plate  95 . An intake valve restrictor  108  can be clamped between the rivet  107  and the hub  106 . The surface  109  terminates at an edge  110  ( FIGS. 13 and 14 ). When air is drawn into the pump cylinder  60  during an intake stroke of the piston  63 , the radial fingers  113  can bend and the plurality of valve members  104  separate from the valve plate assembly  62  to allow air to flow through the intake ports  103 . 
         [0121]      FIG. 13  is a cross-sectional view of the valve plate assembly and  FIG. 14  is a front-side view of the valve plate assembly. The valve plate assembly  62  includes a valve plate  95  which can be generally flat and which can mount a plurality of intake valves  96  ( FIG. 14 ) and a plurality of outlet valves  97  ( FIG. 12 ). In an embodiment, the valve plate assembly  62  ( FIGS. 10 and 12 ) can be clamped to a bracket by screws which can pass through the cylinder head  61  (e.g.  FIG. 2 ), the gasket and a plurality of through holes  99  in the valve plate assembly  62  and engage a bracket. A valve member  112  of the outlet valve  97  can cover an exhaust port  111 . A cylinder flange and a gas tight seal can be used in closing the cylinder head assembly. In an embodiment, a flange and seal can be on a cylinder side (herein front-side) of a valve plate assembly  62  and a gasket can be between the valve plate assembly  62  and the cylinder head  61 . 
         [0122]      FIG. 14  illustrates the front side of the valve plate assembly  62  which can have a plurality of exhaust ports  111  (three shown) which are normally closed by the outlet valves  97 . A plurality of a separate circular valve member  112  can be connected through radial fingers  113  ( FIG. 12 ) which can be made of a resilient material to a valve finger hub  114 . The valve finger hub  114  can be secured to the rear side of the valve plate assembly  62  by the rivet  107 . Optionally, the cylinder head  61  can have a head rib  118  ( FIG. 13 ) which can project over and can be spaced a distance from the valve members  112  to restrict movement of the exhaust valve members  112  and to lessen and control valve impact vibrations and corresponding valve stress. 
         [0123]      FIG. 15A  is a perspective view of a plurality of sound control chambers of an embodiment of the compressor assembly  20 .  FIG. 15A  illustrates an embodiment having four (4) sound control chambers. The number of sound control chambers can vary widely in a range of from one to a large number, e.g. 25, or greater. In non-limiting example, in an embodiment, a compressor assembly  20  can have a fan sound control chamber  550  (also herein as “fan chamber  550 ”), a pump sound control chamber  491  (also herein as “pump chamber  491 ”), an exhaust sound control chamber  555  (also herein as “exhaust chamber  555 ”), and an upper sound control chamber  480  (also herein as “upper chamber  480 ”). 
         [0124]      FIG. 15B  is a perspective view of sound control chambers having optional sound absorbers. The optional sound absorbers can be used to line the inner surface of housing  21 , as well as both sides of partitions which are within the housing  21  of the compressor assembly  20 . 
         [0125]      FIG. 16A  is a perspective view of sound control chambers with an air ducting shroud  485 .  FIG. 16A  illustrates the placement of air ducting shroud  485  in coordination with, for example, the fan chamber  550 , the pump sound control chamber  491 , the exhaust sound control chamber  555 , and the upper sound control chamber  480 . 
         [0126]      FIG. 16B  is a perspective view of sound control chambers having optional sound absorbers. The optional sound absorbers can be used to line the inner surface of housing  21 , as well as both sides of partitions which are within the housing  21  of compressor assembly  20 . 
         [0127]      FIG. 17  is a first table of embodiments of compressor assembly range of performance characteristics. The compressor assembly  20  can have values of performance characteristics as recited in  FIG. 17  which are within the ranges set forth in  FIG. 17 . 
         [0128]      FIG. 18  is a second table of embodiments of ranges of performance characteristics for the compressor assembly  20 . The compressor assembly  20  can have values of performance characteristics as recited in  FIG. 18  which are within the ranges set forth in  FIG. 18 . 
         [0129]    The compressor assembly  20  achieves efficient heat transfer. The heat transfer rate can have a value in a range of from 25 BTU/min to 1000 BTU/min. The heat transfer rate can have a value in a range of from 90 BTU/min to 500 BTU/min. In an embodiment, the compressor assembly  20  can exhibit a heat transfer rate of 200 BTU/min. The heat transfer rate can have a value in a range of from 50 BTU/min to 150 BTU/min. In an embodiment, the compressor assembly  20  can exhibit a heat transfer rate of 135 BTU/min. In an embodiment, the compressor assembly  20  exhibited a heat transfer rate of 84.1 BTU/min. 
         [0130]    The heat transfer rate of a compressor assembly  20  can have a value in a range of 60 BTU/min to 110 BTU/min. In an embodiment of the compressor assembly  20 , the heat transfer rate can have a value in a range of 66.2 BTU/min to 110 BTU/min; or 60 BTU/min to 200 BTU/min. 
         [0131]    The compressor assembly  20  can have noise emissions reduced by e.g., slower fan and/or slower motor speeds, use of a check valve muffler, use of tank vibration dampeners, use of tank sound dampeners, use of a tank dampening ring, use of tank vibration absorbers to dampen noise to and/or from the tank walls which can reduce noise. In an embodiment, a two stage intake muffler can be used on the pump. A housing having reduced or minimized openings can reduce noise from the compressor assembly. As disclosed herein, the elimination of line of sight to the fan and other components as attempted to be viewed from outside of the compressor assembly  20  can reduce noise generated by the compressor assembly. Additionally, routing cooling air through ducts, using foam lined paths and/or routing cooling air through tortuous paths can reduce noise generation by the compressor assembly  20 . 
         [0132]    Additionally, noise can be reduced from the compressor assembly  20  and its sound level lowered by one or more of the following, employing slower motor speeds, using a check valve muffler and/or using a material to provide noise dampening of the housing  21  and its partitions and/or the compressed air tank  150  heads and shell. Other noise dampening features can include one or more of the following and be used with or apart from those listed above, using a two-stage intake muffler in the feed to a feed air port  952 , elimination of line of sight to the fan and/or other noise generating parts of the compressor assembly  20 , a quiet fan design and/or routing cooling air routed through a tortuous path which can optionally be lined with a sound absorbing material, such as a foam. Optionally, fan  200  can be a fan which is separate from the shaft  43  and can be driven by a power source which is not shaft  43 . 
         [0133]    In an example, an embodiment of compressor assembly  20  achieved a decibel reduction of 7.5 dBA. In this example, noise output when compared to a pancake compressor assembly was reduced from about 78.5 dBA to about 71 dBA. 
       Example 1 
       [0134]      FIG. 19  is a first table of example performance characteristics for an example embodiment.  FIG. 19  contains combinations of performance characteristics exhibited by an embodiment of compressor assembly  20 . 
       Example 2 
       [0135]      FIG. 20  is a second table of example performance characteristics for an example embodiment.  FIG. 20  contains combinations of further performance characteristics exhibited by an embodiment of compressor assembly  20 . 
       Example 3 
       [0136]      FIG. 21  is a table containing a third example of performance characteristics of an example compressor assembly  20 . In the Example of  FIG. 21 , a compressor assembly  20 , having an air ducting shroud  485 , a dampening ring  700 , an intake muffler  900 , four sound control chambers, a fan cover, four foam sound absorbers and a tank seal  600  exhibited the performance values set forth in  FIG. 21 . 
         [0137]    The pump assembly  25  (e.g.  FIG. 22 ) can be mounted to the air tank  150  and can have the housing  21 . The housing  21  can have one or more openings through which noise generated by the pump assembly  25  can pass. One such opening can be around the base of the housing  21  where the shroud is proximate to the air tank and herein is exemplified by a tank gap  599 . In an embodiment, noise emitted by compressor assembly  20  can be reduced by sealing the tank gap  599 , e.g. with a tank seal  600  (e.g.  FIG. 24 ) 
         [0138]    Parts, for example, the tank seal  600  (e.g.  FIG. 24 ), can be designed to minimize, eliminate and/or seal, the tank gap  599 . In embodiments, the tank gap  599  can be sealed or closed by the tank seal  600 . 
         [0139]    The fewer openings which are present in the housing  21 , the less total open area exists in the housing for noise to escape through unabated. In an embodiment, other openings, or gaps which exist in the housing  21  of the compressor assembly  20 , or pieces or components thereof, can be eliminated, closed or sealed to reduce the noise emitted from the compressor assembly  20 . In an embodiment, openings or gaps associated with one or a plurality of quick connections, such as the first quick connection  305  and the second quick connection  310 , or with one or a plurality of a pressure regulator  320  can be eliminated, closed or sealed to reduce the noise emitted from the compressor assembly  20 . In an embodiment, gaps around the dashboard  300  or the manifold  303  can be sealed or blocked by foam to reduce the noise emitted by the compressor assembly  20 . In an embodiment, the sound level of a compressor assembly  20  can be reduced by reducing the amount of openings present in the housing  21 , or pieces thereof. 
         [0140]      FIG. 22  is a perspective view of a pump assembly  25  and the compressed gas tank  150  having the tank gap  599 .  FIG. 22  illustrates the tank gap  599  located between the compressed gas tank  150  and a housing rim  605 . In an embodiment, the housing rim  605  can have a front housing rim  610 , a fan-side housing rim  620 , a rear housing rim  630  and a pump-side housing rim portion  640  (e.g.  FIG. 29 ). The pump-side housing rim portion  640  can have portions of the front housing rim  610  and the rear housing rim  630 . 
         [0141]      FIG. 23  is a fan-side view of a pump assembly  25  and the compressed gas tank  150  having a tank gap  599 . The fan-side portion of the tank gap  599  is located between the compressed gas tank  150  and a housing rim  605 . 
         [0142]      FIG. 24  is a perspective view of the pump assembly  25  and the compressed gas tank  150  having a tank seal  600  for sealing the tank gap  599 . The tank seal  600  can be fit between the housing rim  605  and the compressed gas tank  150  to seal the tank gap  599 . The tank seal  600  can seal or close the tank gap  599  to reduce sound emitted through the tank gap  599 . 
         [0143]    The tank gap  599  can have a distance between the housing rim  605  and the compressed gas tank  150  which can have a value in e.g. a range of from 0.01 in to 6 in, or e.g. a range of from 0.05 in to 5 in. In an embodiment, the distance between the housing rim  605  and the compressed gas tank  150  can have a value in a range of from 1.0 in to 2.0 in. In an embodiment, the distance between the housing rim  605  and the compressed gas tank  150  can have a value in a range of from 0.15 in to 1.0 in. In an embodiment, the distance between the housing rim  605  and the compressed gas tank  150  can have a value in a range of from 0.05 in to 0.75 in. In an embodiment, the housing rim  605  can have a value of 0.250 in. 
         [0144]    There can also be a distance between the closest portion of the pump assembly  25  components and the compressed gas tank  150  which can have a value in a range of from 0.1 in to 8 in. In an embodiment, a sound absorbing cushion can be placed between the pump assembly  25  and the compressed gas tank  150 . 
         [0145]    The use of a tank seal  600  can achieve a noise reduction having a value in a range of from 0.5 dBA to 15 dBA, or a greater. In further embodiments, the use of a tank seal  600  can achieve a noise reduction having a value in a range of from 0.5 dBA to 10 dBA; or from 0.5 dBA to 7 dBA; or from 1.4 dBA to 15 dBA; or from 5 dBA to 10 dBA; or from 0.5 dBA to 8 dBA; or from 0.5 dBA to 5 dBA; or from 5 dBA to 8 dBA. 
         [0146]    In an embodiment, a decibel reduction of 2.5 dBA can be achieved by using a tank seal  600  to reduce the noise output of a compressor assembly  20 . In this example embodiment, the noise output of a compressor assembly  20  can be reduced from 70.5 dBA to 68 dBA using a tank seal  600 . 
         [0147]    The tank gap  599  can be sealed by a tape, or a duct tape, or a foam tape, or a rubber tape, or a Gorilla Tape® (The Gorilla Glue Company, 4550 Red Bank Expressway Cincinnati, Ohio 45227). Alternatively, the tank gap  599  can be sealed by an expandable spray foam, a caulk or a silicone. The tank gap  599  can also be sealed by a cushion material including, but not limited to, a cloth, felt, or other type of strip or appropriately shaped material which can conform in shape, of deform, to seal tank gap  599 . The rubber or rubber-like material could be over-molded onto the housing rim  605 . In an embodiment, the rubber or rubber-like material could be manufactured as a separate piece for assembly as a seal. For example, the tank gap  599  can be sealed by over-molding on the shroud with low durometer material, or other material. Alternatively, the tank gap  599  can be sealed by a foam strip. For example, the tank gap  599  can be sealed by a mat, a tank blanket, a foam or other tank covering onto which the housing rim  605  can be set and which can seal the tank gap  599 . In an embodiment, an ethylene propylene diene monomer (EPDM) sponge rubber can be used to seal or fill gaps or openings and/or to reduce or muffle noise. 
         [0148]    In an embodiment, tank gap  599  can be closed and/or sealed by a rubber or foam strip which can be attached to the shroud, or the tank, or held by frictional attachment, so that the rubber or foam strip can fill the gap when the parts are assembled, thus providing a seal to prevent an amount of noise from escaping from compressor assembly  20  through tank gap  599  and/or emanating from compressor assembly  20 . 
         [0149]      FIG. 25  is a detail of the tank seal  600  of  FIG. 24  sealing the tank gap  599  by being fit between the housing rim  605  and compressed gas tank  150 . 
         [0150]      FIG. 26  is a fan-side view of the pump assembly  25  and compressed gas tank  150  having the tank seal  600 . 
         [0151]      FIG. 27  is a fan-side sectional view of a pump assembly  25  and compressed gas tank  150  having a tank seal  600 . The tank seal is shown in a sectional view of a front seal portion  608  and a rear seal portion  612  ( FIG. 31 ). 
         [0152]      FIG. 28A  is an exemplary detail of the tank seal. The tank seal  600  has a housing seal  623  optionally connected to a seal bulb  627 . In an embodiment, housing seal  623  can be U-shaped, V-shaped or other shape to mate with housing rim  605 . In an embodiment, the housing seal  623  can have seal hook  621 . In an embodiment, the seal hook  621  can engage with a portion of housing rim  605 . In an embodiment, the housing seal  623  can optionally have a seal rib  629 . In an embodiment, the seal rib  629  can be metal, plastic, rubber, fiberglass, carbon fiber, or a rigid or a semi-rigid material. 
         [0153]    In an embodiment, the tank seal  600  can be compressed under a force having a value in a range of from 0.25 lbf/in̂2 to 50 lbf/in̂2, or greater. 
         [0154]    In an embodiment, the seal bulb  627  can have a seal bulb outer diameter  631  (also herein as “seal bulb OD  631 ”; see also  FIG. 28B ) from 0.15 in to 3.0 in, or greater. In an embodiment, the seal bulb OD  631  can be 0.25 in. In an embodiment, the seal bulb OD  631  can be 0.375 in. In an embodiment, the seal bulb OD  631  can be 0.5 in. In an embodiment, the seal bulb OD  631  can be 0.75 in. 
         [0155]    The seal bulb  627  can have an outer diameter, when not compressed of, e.g. 0.375 in. When compressed, the seal bulb  627  can change shape, or deform, under force to a shape which can conform to at least a portion of the compressed gas tank  150  and which can seal the tank gap  599 . 
         [0156]    The housing seal base portion  626  ( FIG. 28A ) of the housing seal  623  and the seal bulb  627  in a compressed state can seal or close the tank gap  599 . 
         [0157]    In an embodiment, the tank seal  600  can have a pump assembly side  636  and an outside  638 . A difference in sound level across the tank seal  600  as measured from a location on or proximate to the pump assembly side  636  to a location on or proximate to the outside  638  can be a value in a range of from 0.25 dBA to 15 dBA. A difference in sound level across the tank seal  600  as measured from a location on or proximate to the pump assembly side  636  to a location on or proximate to the outside  638  can be a value in a range of from 0.3 dBA to 10 dBA. A difference in sound level across the tank seal  600  as measured from a location on or proximate to the pump assembly side  636  to a location on or proximate to the outside  638  can be a value in a range of from 2.0 dBA to 10 dBA. The difference in sound level across the tank seal  600  as measured at the aforementioned locations can have a value in a range of from 2.5 dBA to 8 dBA, in a range of from 5 dBA to 8 dBA. 
         [0158]      FIG. 28B  is a cross-sectional view of a tank seal identifying a housing fitting height  633 . The housing fitting height can be the height of the U-shaped portion of the seal  600 . In an embodiment, the housing fitting height  633  can have a value in a range of 0.15 in to 6.0 in, or greater. In an embodiment, the housing fitting height  633  can be 0.25 in. The housing fitting height  633  can be 0.375 in. In an embodiment, the housing fitting height  633  can be 0.5 in. In an embodiment, the housing fitting height  633  can be 1 in, or greater. The seal height  635  of seal  600  can range, e.g. from 0.3 in to 6 inches, or greater. 
         [0159]    In an embodiment, in which seal  600  is over-molded onto the housing rim  605  the height of such over-molded seal can be less than 0.3 in, an can have a range of e.g. from 0.1 in to 3.0 in, or greater. 
         [0160]      FIG. 28C  is a side view of a tank seal  600 . 
         [0161]      FIG. 29  is a pump-side view of a pump assembly  25  and compressed gas tank  150  having tank seal  600  which can seal the tank gap  599  between the housing rim  605  and compressed gas tank  150 . 
         [0162]      FIG. 30  is an exploded front perspective view of the pump assembly  25  and compressed gas tank  150  having the tank seal  600 . In  FIG. 30 , the housing rim  605  can have the front housing rim  610 , the fan-side housing rim  620 , the rear housing rim  630  and the pump-side housing rim  640  ( FIG. 31 ).  FIG. 30  also shows tank seal  600  apart from the compressed gas tank  150 . In  FIG. 30 , the housing rim  605 , tank seal  600  and tank seal line  607  are illustrated separately in an alignment to illustrate how an assembly can bring these pieces together. Assembly of these pieces can be accomplished by a variety of methods. In an embodiment, the tank seal  600  can be assembled between the housing rim  605  and the compressed gas tank  150  as illustrated in e.g.  FIGS. 30 and 31  which can be assembled as in e.g.  FIG. 24 . 
         [0163]      FIG. 31  is an exploded rear perspective view of the pump assembly  25  and compressed gas tank  150  having the tank seal  600 . 
         [0164]      FIG. 32  is an embodiment of the tank seal  600 . In this example, the tank seal  600  has a first seal portion  602  and second seal portion  604 . 
         [0165]      FIG. 33  is a view having piece of a tank seal  600  which, for illustrative purposes, has a seal  606  portion which is shown not in contact with compressed air tank  150 .  FIG. 33  thus illustrates an uncompressed state of the portion not in contact with the compressed gas tank  150 . 
         [0166]      FIG. 34  illustrates an embodiment of a tank seal made of foam and forming a foam barrier  650  which can provide a barrier between a noise source and an operator to achieve a reduction in noise.  FIG. 34  illustrates a portion of a foam barrier  650 , which can have a first foam barrier  652  and a second foam barrier  654 . 
         [0167]    Foam can be used to muffle the noise from the plurality of exhaust ports  31 . In an embodiment, the foam can have a porosity to allow exiting exhaust air flow through the plurality of exhaust ports  31  for sufficient cooling. In an embodiment, foam can be used to muffle the noise from the intake ports  182  for the cooling air. 
         [0168]    In an embodiment, a sound absorbing foam can be, e.g. a polyurethane foam and can have a value of density in a range from 0.8 lb/ft̂3 to 5.0 lb/ft̂3. The foam can be used as a tank seal  600  forming a noise barrier or sound absorber. In an embodiment, the foam can have a value of density in a range from 1.6 lb/ft̂3 to 2.0 lb/ft̂3, or e.g. have a value of density of 1.8 lb/ft̂3, and can be used as the tank seal  600  to form a noise barrier or sound absorber. In an embodiment, the foam can be flame retardant. In an embodiment, the foam can be used in the pump chamber  491  which can contain at least the pump and motor components to reduce noise emissions from at least the pump assembly  25 . In an embodiment, a foam material can cover at least a portion of the tank surface which is present in the pump chamber  491 . 
         [0169]    The scope of this disclosure is to be broadly construed. It is intended that this disclosure disclose equivalents, means, systems and methods to achieve the devices, designs, operations, control systems, controls, activities, mechanical actions, fluid dynamics and results disclosed herein. For each mechanical element or mechanism disclosed, it is intended that this disclosure also encompasses within the scope of its disclosure and teaches equivalents, means, systems and methods for practicing the many aspects, mechanisms and devices disclosed herein. Additionally, this disclosure regards a compressor and its many aspects, features and elements. Such an apparatus can be dynamic in its use and operation. This disclosure is intended to encompass the equivalents, means, systems and methods of the use of the compressor assembly and its many aspects consistent with the description and spirit of the apparatus, means, methods, functions and operations disclosed herein. The claims of this application are likewise to be broadly construed. 
         [0170]    The description of the inventions herein in their many embodiments is merely exemplary in nature and, thus, variations that do not depart from the gist of the invention are intended to be within the scope of the invention and the disclosure herein. Such variations are not to be regarded as a departure from the spirit and scope of the invention. 
         [0171]    It will be appreciated that various modifications and changes can be made to the above described embodiments of a compressor assembly as disclosed herein without departing from the spirit and the scope of the following claims.