Title:
Cam driven piston compressor apparatus
Kind Code:
A1


Abstract:
A compressor apparatus for compressing fluids includes a compression vessel having a collapsible vessel internal space having an expanded size and a compressed size, the compression vessel having intake structure for passing fluid into the vessel internal space from a fluid source and output structure for passing fluid out of the vessel internal space; a rotatable cam structure having a cam structure rotational axis and at least one radial cam protrusion positioned to periodically abut the compression vessel and compress the vessel internal space; a rotational drive mechanism drivably connected to the rotatable cam structure for rotatably driving the cam structure and the cam protrusion about the cam structure rotational axis; and a compression vessel expansion mechanism for expanding the vessel internal space to its expanded size subsequent to each compression of the vessel internal space.



Inventors:
Scalzi, Saverio (Hollywood, FL, US)
Application Number:
11/284335
Publication Date:
05/24/2007
Filing Date:
11/21/2005
Primary Class:
International Classes:
F04B19/00
View Patent Images:
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Primary Examiner:
BAYOU, AMENE SETEGNE
Attorney, Agent or Firm:
OLTMAN, FLYNN & KUBLER (FORT LAUDERDALE, FL, US)
Claims:
I claim as my invention:

1. A compressor apparatus for compressing fluids, comprising: a compression vessel having a collapsible vessel internal space having an expanded size and a compressed size, the compression vessel having intake means for passing fluid into the vessel internal space from a fluid source and output means for passing fluid out of the vessel internal space; a rotatable cam structure having a cam structure rotational axis and at least one radial cam protrusion positioned to periodically abut said compression vessel and compress the vessel internal space; rotational drive means drivably connected to the rotatable cam structure for rotatably driving the cam structure and the cam protrusion about the cam structure rotational axis; and a compression vessel expansion means for expanding the vessel internal space to its expanded size subsequent to each compression of the vessel internal space; such that compression of the vessel internal space drives fluid within the vessel internal space out of the vessel through the output means, and then the compression vessel return means expands the vessel internal space, thereby drawing fluid through the intake means into the vessel internal space from the fluid source, in a repeating cycle.

2. The compressor apparatus of claim 1, wherein said compression vessel comprises a cylinder and piston assembly having a cylinder interior and said vessel internal space comprise the cylinder interior.

3. A compressor apparatus for compressing fluids, comprising: at least one cylinder and piston assembly comprising a cylinder having a cylinder head and a tubular cylinder side wall and a piston structure slidably retained within said cylinder, said cylinder having an intake port fitted with an intake valve for passing fluid into said cylinder from a fluid source and an output port fitted with an output valve for passing fluid out of said cylinder; valve operating means in operational relation with said intake valve and said output valve; a rotatable cam structure having a cam structure rotational axis and at least one radial cam protrusion positioned to periodically abut and displace said piston structure inwardly toward said cylinder head; rotational drive means drivably connected to said rotatable cam structure for rotatably driving said cam structure and said cam protrusion about said cam structure rotational axis; and a piston structure return means for displacing said piston structure outwardly and away from said cylinder head subsequent to each piston structure inward displacement; such that said valve operating means opens said output valve and said cam protrusion abuts and displaces said piston structure toward said cylinder head, driving fluid within said cylinder out of said cylinder through said output port, and then said valve operating means closes said output valve and opens said intake valve and said piston structure return means displaces said piston structure outwardly, away from said cylinder head and said intake port, thereby drawing fluid through said intake port into said cylinder from the fluid source, in a repeating cycle.

4. The compressor apparatus of claim 3, wherein said cylinder and piston assembly and said cam structure are both fastened to an apparatus framework to position said cylinder and piston assembly and said cam structure in operational relation with each other.

5. The compressor apparatus of claim 3, wherein said apparatus framework comprises an apparatus housing.

6. The compressor apparatus of claim 3, wherein said intake port is covered by an air filter means.

7. The compressor apparatus of claim 3, wherein said at least one cam protrusion is at least one cam arm and wherein said cam structure comprises a cam wheel having a cam wheel circumferential surface to which said at least one cam arm is mounted.

8. The compressor apparatus of claim 3 additionally comprising a flywheel mounted to rotate in unison with said cam structure to provide smooth cam structure rotation.

9. The compressor apparatus of claim 3, wherein said piston structure comprises a piston connected to a piston rod extending out of said cylinder opposite said cylinder head having a piston rod abutment end.

10. The compressor apparatus of claim 3, wherein said piston is fitted with at least one piston ring seated in a circumferential piston ring groove to slide sealingly along said cylinder side wall.

11. The compressor apparatus of claim 3, wherein said cylinder comprises a cup-shaped cylinder bottom wall opposite said cylinder head with a central piston rod passing port for funneling blow-by oil to said piston rod such that said piston rod is lubricated by the oil and carries oil out of the cylinder with each cylinder and piston assembly cycle.

12. The compressor apparatus of claim 11, wherein said piston rod comprises at least one oil receiving depression for receiving and retaining oil to carry oil out of said cylinder through said piston rod passing port.

13. The compressor apparatus of claim 3, wherein said rotational drive means comprises an electric drive motor connected to said cam structure with a drive connection.

14. The compressor apparatus of claim 13, wherein said drive connection comprises a drive belt engaging a motor pulley mounted on the motor drive shaft and a cam structure pulley mounted on a cam structure axle.

15. The compressor apparatus of claim 4, wherein said piston structure return means comprises a piston rod biasing spring mounted to be compressed between a framework.

16. The compressor apparatus of claim 15, wherein said piston rod biasing spring is a coil spring encircling said piston rod and having a progressively narrowing, conical configuration.

17. The compressor apparatus of claim 4, wherein said piston structure return means comprises a piston return lever pivotally mounted on a lever fulcrum pin secured to said apparatus framework, having a return lever first end engaging said piston structure and a return lever second end positioned for periodic displacement by said at least one cam protrusion.

18. The compressor apparatus of claim 3, wherein said cam protrusions are selectively movable out of rotational alignment with said piston structure such that a desired number of said cam protrusions can be selected to displace said piston structure for each cam structure rotation; such that the volume of fluid compressed per cam structure rotation can be altered to accommodate requirements of any of a wide variety of applications.

19. The compressor apparatus of claim 7, wherein each said cam arm comprises an expanded mounting end which fits engagingly into any of a plurality of cam arm channels each having an outwardly narrowing arm engaging channel outward channel opening and extending laterally across the width of and spaced periodically around said cam wheel circumferential surface; such that each cam arm is slidably retained within a corresponding said cam arm channel.

20. The compressor apparatus of claim 19, wherein said cam wheel circumferential surface is sufficiently wide and said cam arm channels therefore sufficiently long that one said cam arm can be slid to a first channel end of the given said cam arm channel and thus to a first side of said cam wheel circumferential surface to align with and abut said piston structure during cam wheel rotation, and slid to a second channel end and thus to a second side of said cam wheel circumferential surface to be out of registration with said piston structure during cam wheel rotation; such that a selected number of said cam arms can be slid to said first channel end to register with said piston structure as needed for a given apparatus application.

21. The compressor apparatus of claim 20, wherein said cam arms are each moved to one of said first side of said cam wheel circumferential surface and said second side of said cam wheel circumferential surface by electro magnets mounted adjacent opposing faces of said cam wheel and adjacent to the cam wheel circumferential surface; such that activation of either said electro magnet pulls each immediately adjacent cam arm to the adjacent said side of said cam wheel circumferential surface, and the given said electro magnet can be activated and deactivated as said cam wheel is rotated by said drive means such that only selected said cam arms are moved to a given side of said cam wheel circumferential surface to provide a desired number of said cam arms in registration with said at least one cylinder and piston assembly associated with said cam wheel.

22. The compressor apparatus of claim 3, comprising a plurality of said cylinder and piston assemblies positioned to extend radially and equidistantly from said cam structure, such that said at least one cam protrusion abuts and displaces each said piston structure in sequence with each said cam structure rotation.

23. The compressor apparatus of claim 3, comprising multiple said cam structure and cylinder units mounted on a common axle and thus driven by a common motor drive means, and individual clutch means for each cam structure, such that only a selected number of said cam structures rotate with said drive means.

Description:

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates generally to the field of compression and storage of fluids and particularly to compression of gaseous matter. More specifically the present invention relates to a compressor apparatus including at least one cylinder and piston assembly including a cylinder having a cylinder head and a tubular cylinder side wall and a piston structure slidably retained within the tubular cylinder side wall, the cylinder head having an intake port fitted with an intake valve for passing fluid into the cylinder from a fluid source and an output port fitted with an output valve for passing fluid out of the cylinder such as to a fluid reservoir, valve operating means, a rotatable cam structure in the form of a cam wheel having a cam structure axle and radial cam protrusions in the form of cam arms positioned to periodically abut and displace the piston structure inwardly toward the cylinder head, and rotational drive means drivably connected to the rotatable cam wheel for rotatably driving the cam wheel and the cam arms about the cam wheel rotational axis, and a piston structure return means for displacing the piston structure outwardly away from the cylinder head subsequent to each piston structure inward displacement. The valve operating means opens the output valve and a cam arm abuts and displaces the piston structure toward the cylinder head, driving fluid within the cylinder out of the cylinder through the output port, and then the valve operating means closes the output valve and opens the intake valve and the piston structure return means displaces the piston structure outwardly, away from the cylinder head and the intake port, thereby drawing fluid through the intake port into the cylinder from the fluid source, in a periodically repeating cycle. The cylinder and piston assembly and cam wheel preferably are both fastened to an apparatus framework to position them in operational relation with each other. The apparatus framework preferably includes an apparatus housing enclosing at least the cam wheel. The intake port optionally is covered by an air filter retained within an air filter housing.

The number of cam arms provided on the cam structure determines the number of compression cycles the cylinder and piston assembly performs for each revolution of the cam structure, and is selected to meet the requirements of the given application. A flywheel preferably is provided adjacent the cam wheel and mounted to the cam wheel axle to provide smooth cam rotation. The piston structure preferably includes a piston connected to a piston rod. The rotational drive means preferably includes an electric drive motor connected to the cam structure with a belt and pulleys or other drive connection.

The number of cam arms on the cam structure preferably can be altered such that the volume of fluid compressed per cam structure revolution can be altered to accommodate any of a wide variety of applications. Another variation of the present compressor apparatus includes a plurality of cylinder and piston assemblies positioned and secured to the apparatus framework to extend radially and equidistantly from the cam structure to be operated by the cam arms in sequence. Yet another variation of the compression apparatus includes multiple cam structure and cylinder units. The cam structures preferably are cam wheels mounted on a common cam structure axle and thus driven by a common motor drive means.

2. Description of the Prior Art

There have long been compressors for compressing gaseous matter for storage or immediate use. These prior compressors typically have included a cylinder and piston combination driven by a motor or engine. A problem with these prior compressors has been that they can produce only one compression per motor or engine revolution, limiting compression to a specific rate which may or may not be suited for a given application. If a larger compression rate is needed, a different and larger compressor must be located.

It is thus an object of the present invention to provide a compressor apparatus which can compress a fluid at any of several different rates selectable for a given job or application, the apparatus including a cam structure rotatably driven by drive means and at least one cylinder and piston assembly driven through compression cycles by contact with at least one cam protrusion on the rotating cam structure.

It is another object of the present invention to provide such a compressor apparatus for which a specific desired rate of fluid compression can be selected by: selecting the number of cylinder and piston assembly compressions per revolution of motor drive means by altering the number of cam protrusions on the rotating cam structure, or by selecting the number of cylinder and piston assemblies operated with each revolution of the motor drive means, or by selecting the number of cam structure and corresponding cylinder and piston assemblies, or by altering all three variables as needed.

It is still another object of the present invention to provide such a compressor apparatus with which such selections can be made automatically by computer program operated electric switches.

It is finally an object of the present invention to provide such a compressor apparatus which is reliable, durable, requires less electricity to operate, and economical to manufacture.

SUMMARY OF THE INVENTION

The present invention accomplishes the above-stated objectives, as well as others, as may be determined by a fair reading and interpretation of the entire specification.

A compressor apparatus is provided for compressing fluids, including a compression vessel having a collapsible vessel internal space having an expanded size and a compressed size, the compression vessel having intake structure for passing fluid into the vessel internal space from a fluid source and output structure for passing fluid out of the vessel internal space; a rotatable cam structure having a cam structure rotational axis and at least one radial cam protrusion positioned to periodically abut the compression vessel and compress the vessel internal space; a rotational drive mechanism drivably connected to the rotatable cam structure for rotatably driving the cam structure and the cam protrusion about the cam structure rotational axis; and a compression vessel expansion mechanism for expanding the vessel internal space to its expanded size subsequent to each compression of the vessel internal space; so that compression of the vessel internal space drives fluid within the vessel internal space out of the vessel through the output structure, and then the compression vessel return mechanism expands the vessel internal space, thereby drawing fluid through the intake structure into the vessel internal space from the fluid source, in a repeating cycle.

The compression vessel preferably includes a cylinder and piston assembly having a cylinder interior and the vessel internal space comprise the cylinder interior.

A compressor apparatus for compressing fluids is further provided, including at least one cylinder and piston assembly including a cylinder having a cylinder head and a tubular cylinder side wall and a piston structure slidably retained within the cylinder, the cylinder having an intake port fitted with an intake valve for passing fluid into the cylinder from a fluid source and an output port fitted with an output valve for passing fluid out of the cylinder; a valve operating mechanism in operational relation with the intake valve and the output valve; a rotatable cam structure having a cam structure rotational axis and at least one radial cam protrusion positioned to periodically abut and displace the piston structure inwardly toward the cylinder head; a rotational drive mechanism drivably connected to the rotatable cam structure for rotatably driving the cam structure and the cam protrusion about the cam structure rotational axis; and a piston structure return mechanism for displacing the piston structure outwardly and away from the cylinder head subsequent to each piston structure inward displacement; so that the valve operating mechanism opens the output valve and the cam protrusion abuts and displaces the piston structure toward the cylinder head, driving fluid within the cylinder out of the cylinder through the output port, and then the valve operating mechanism closes the output valve and opens the intake valve and the piston structure return mechanism displaces the piston structure outwardly, away from the cylinder head and the intake port, thereby drawing fluid through the intake port into the cylinder from the fluid source, in a repeating cycle, as in any conventional cylinder and piston operation.

The cylinder and piston assembly and the cam structure preferably are both fastened to an apparatus framework to position the cylinder and piston assembly and the cam structure in operational relation with each other. The apparatus framework preferably includes an apparatus housing. The intake port preferably is covered by an air filter structure. The at least one cam protrusion preferably is at least one cam arm and the cam structure preferably includes a cam wheel having a cam wheel circumferential surface to which the at least one cam arm is mounted. The compressor apparatus preferably additionally includes a flywheel mounted to rotate in unison with the cam structure to provide smooth cam structure rotation.

The piston structure preferably includes a piston connected to a piston rod extending out of the cylinder opposite the cylinder head having a piston rod abutment end. The piston preferably is fitted with at least one piston ring seated in a circumferential piston ring groove to slide sealingly along the cylinder side wall. The cylinder preferably includes a cup-shaped cylinder bottom wall opposite the cylinder head with a central piston rod passing port for funneling blow-by oil to the piston rod so that the piston rod is lubricated by the oil and carries oil out of the cylinder with each cylinder and piston assembly cycle. The piston rod preferably includes at least one oil receiving depression for receiving and retaining oil to carry oil out of the cylinder through the piston rod passing port.

The rotational drive mechanism preferably includes an electric drive motor connected to the cam structure with a drive connection. The drive connection preferably includes a drive belt engaging a motor pulley mounted on the motor drive shaft and a cam structure pulley mounted on a cam structure axle.

The piston structure return mechanism preferably includes a piston rod biasing spring mounted to be compressed between a framework. The piston rod biasing spring preferably is a coil spring encircling the piston rod and having a progressively narrowing, conical configuration. The piston structure return mechanism preferably includes a piston return lever pivotally mounted on a lever fulcrum pin secured to the apparatus framework, having a return lever first end engaging the piston structure and a return lever second end positioned for periodic displacement by the at least one cam protrusion.

The cam protrusions may be fixed cams but preferably are selectively movable out of rotational alignment with the piston structure so that a desired number of the cam protrusions can be selected to displace the piston structure for each cam structure rotation; so that the volume of fluid compressed per cam structure rotation can be altered to accommodate requirements of any of a wide variety of applications. The where each cam arm includes an expanded mounting end which fits engagingly into any of several cam arm channels each having an outwardly narrowing arm engaging channel outward channel opening and extending laterally across the width of and spaced periodically around the cam wheel circumferential surface; so that each cam arm is slidably retained within a corresponding the cam arm channel. The cam wheel circumferential surface preferably is sufficiently wide and the cam arm channels therefore sufficiently long that one the cam arm can be slid to a first channel end of the given the cam arm channel and thus to a first side of the cam wheel circumferential surface to align with and abut the piston structure during cam wheel rotation, and slid to a second channel end and thus to a second side of the cam wheel circumferential surface to be out of registration with the piston structure during cam wheel rotation; so that a selected number of the cam arms can be slid to the first channel end to register with the piston structure as needed for a given apparatus application.

The cam arms preferably are each moved to one of the first side of the cam wheel circumferential surface and the second side of the cam wheel circumferential surface by electro magnets mounted adjacent opposing faces of the cam wheel and adjacent to the cam wheel circumferential surface; so that activation of either the electro magnet pulls each immediately adjacent cam arm to the adjacent the side of the cam wheel circumferential surface, and the given the electro magnet can be activated and deactivated as the cam wheel is rotated by the drive mechanism so that only selected cam arms are moved to a given side of the cam wheel circumferential surface to provide a desired number of cam arms in registration with the at least one cylinder and piston assembly associated with the cam wheel.

The compressor apparatus optionally includes several of the cylinder and piston assemblies positioned to extend radially and equidistantly from the cam structure, so that the at least one cam protrusion abuts and displaces each piston structure in sequence with each the cam structure rotation. The compressor apparatus optionally additionally or alternatively includes multiple cam structure and cylinder units mounted on a common axle and thus driven by a common motor drive mechanism, and individual clutches for each cam structure, so that only a selected number of the cam structures rotate with the drive mechanism.

BRIEF DESCRIPTION OF THE DRAWINGS

Various other objects, advantages, and features of the invention will become apparent to those skilled in the art from the following discussion taken in conjunction with the following drawings, in which:

FIG. 1 is a side view of the a preferred embodiment of the compressor apparatus with the housing broken away to reveal the cam wheel, cam arms, and a cross-sectional view of the cylinder and piston assembly. Piston return means shown in this FIGURE include the return spring and return lever.

FIG. 2 is an end view of the compressor apparatus of FIG. 1.

FIG. 3 is a close-up cross-sectional side view of the cylinder and piston assembly of FIG. 1.

FIG. 4 is an end view of the apparatus of FIG. 1 but adding the preferred sliding cam arm feature and showing some of the cam arms slid to a first channel ends to register with the piston structure and other cam arms slid to second channel ends to be out of registration with the piston structure. Opposing electro-magnets for moving the cam arms to selected first or second channel ends are also shown.

FIG. 5 is a side view of the cam wheel having the cam arm channels of FIG. 4.

FIG. 6 is an end view of the compressor apparatus of FIG. 5.

FIG. 7 is a side view of the cam wheel of FIG. 5 additionally showing the preferred spring-loaded retaining protrusions for retaining the cam arms at their selected first or second channel ends.

FIG. 8 is an end view of the cam wheel of FIG. 7, showing the preferred central position of the retaining protrusions in the cam arm channels.

FIG. 9 is a view as in FIG. 1, except that a second cylinder and piston assembly is provided, to illustrate the option of providing two or more such assemblies on a given apparatus cam structure and cylinder unit.

FIG. 10 is an end view of the apparatus of FIG. 4, showing an optional second cam structure and cylinder unit, to illustrate the option of providing two or more such units in an individual compressor apparatus.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

As required, detailed embodiments of the present invention are disclosed herein; however, it is to be understood that the disclosed embodiments are merely exemplary of the invention which may be embodied in various forms. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a basis for the claims and as a representative basis for teaching one skilled in the art to variously employ the present invention in virtually any appropriately detailed structure.

Reference is now made to the drawings, wherein like characteristics and features of the present invention shown in the various FIGURES are designated by the same reference numerals.

First Preferred Embodiment

Referring to FIGS. 1-10, a compressor apparatus 10 is disclosed including at least one cylinder and piston assembly 20 having a cylinder 22 having a cylinder head 24 and a tubular cylinder side wall 26 and a piston structure 40 slidably retained within the cylinder side wall 26, the cylinder head 24 having an intake port 32 fitted with an intake valve 34 for passing fluid into the cylinder 22 from a fluid source FS and an output port 36 fitted with an output valve 38 for passing fluid out of the cylinder 22 such as to a fluid reservoir FR, valve operating means 50, a rotatable cam structure 60 having a cam structure rotational axis A and at least one radial cam protrusion 62 positioned to periodically abut and displace the piston structure 40 inwardly toward the cylinder head 24 and rotational drive means 80 drivably connected to the rotatable cam structure 60 for rotatably driving the cam structure 60 and the cam protrusion 62 about the cam structure rotational axis A, and a piston structure return means 90 for displacing the piston structure 40 outwardly away from the cylinder head 24 subsequent to each piston structure 40 inward displacement. As a result, such that the valve operating means 50 opens the output valve 38 and the cam protrusion 62 abuts and displaces the piston structure 40 toward the cylinder head 24, driving fluid within the cylinder 22 out of the cylinder 22 through the output port 36, and then the valve operating means 50 closes the output valve 38 and opens the intake valve 34 and the piston structure return means 90 displaces the piston structure 40 outwardly, away from the cylinder head 24 and the intake port 32, thereby drawing fluid through the intake port 32 into the cylinder 22 from the fluid source FS, in a periodically repeating cycle. Cylinder head 24 preferably is an integral part of the cylinder 22, although it is contemplated that it be made removable for servicing. Cylinder side wall 26 preferably is surrounded by heat fins 26a to increase outer surface area and thus increase the dissipation of heat from compressing a fluid. The cylinder and piston assembly 20 and cam structure 60 preferably are both fastened to an apparatus framework 100 to position them in operational relation with each other. The apparatus framework 100 preferably includes an apparatus housing 110. The intake port 32 optionally is covered by an air filter 122 retained within an air filter housing 124.

The number of cam protrusions 62 provided on the cam structure 60 determines the number of compression cycles the cylinder and piston assembly 20 performs for each revolution of the cam structure 60, and is selected to meet the requirements of the given job or application. The cam structure 60 preferably includes a cam wheel 70 having a cam wheel circumferential surface 72 to which one or more cam protrusions 62 are mounted. The cam protrusions 62 preferably each include a radially extending cam arm mounted to the wheel circumferential surface 72. A flywheel 130 preferably is provided beside the cam wheel 70 and mounted to the cam wheel axle 74 to provide smooth cam structure 60 rotation.

The piston structure 40 preferably includes a piston 42 connected to a piston rod 44 extending out of the cylinder 22 opposite the cylinder head 24 and having a piston rod abutment end 44a fitted with a piston rod abutment end spring-loaded ball bearing 48 to ride over cam protrusions 62 with minimal friction and absorb the impact of abutting cam protrusions 62. The piston rod 44 preferably is fixedly secured to the piston 42 to remain substantially parallel to the cylinder side wall 26. The piston 42 preferably is fitted with conventional piston rings 42a seated in circumferential piston ring grooves 42b to slide sealingly along the cylinder side wall 26. The cylinder 22 preferably has a cylinder bottom wall 28 opposite the cylinder head 24 with a central piston rod passing port 18. Oil O lubricates the cylinder side wall 26 and is retained by the cylinder bottom wall 28, which preferably is cup-shaped to gather the oil O and funnel it toward the piston rod 44. Oil O thus deposited on the piston rod 44 enters and is retained by a longitudinal series of oil gathering depressions 46 in the piston rod 44, preferably in the form of a series of notches 46, and thus is carried by the piston rod 44 out of the cylinder 22. This mechanism removes blow-by oil O accumulated in the cylinder 22 and at the same time lubricates the piston rod 44 so that it moves through the port 18 in the cylinder bottom wall 28 with minimal friction.

The rotational drive means 80 preferably includes an electric drive motor 82 connected to the cam structure 60 with a drive connection. The drive connection extends between the drive motor 82 and the cam structure 60 and preferably takes the form of a drive belt 84 engaging a motor pulley 86 mounted on the motor drive shaft 82a and a cam structure pulley 88 mounted on a cam structure axle 74. The cam structure axle 74 preferably is mounted in bearings retained in axle retaining members 102 and 104 which form part of the apparatus framework 100.

The piston structure return means 90 preferably is a piston rod biasing spring 92 mounted to be compressed between a framework outer brace 106 and a framework inner brace 108 and engaged by a return spring pin (not shown) passing through the piston rod 44. The piston rod biasing spring 92 preferably is a coil spring encircling the piston rod 44 and preferably has a progressively narrowing, conical configuration.

Alternatively or additionally the piston structure return means 90 is a piston return lever 94 rotatably mounted on a lever fulcrum pin 96 secured to the apparatus framework 100. See FIG. 3. A return lever first end 94a engages the piston structure 40 such as the piston rod 44 and a return lever second end 94b is periodically displaced by the cam protrusion 62 or cam protrusions 62. Another alternative or additional piston return means 90 is a piston return solenoid coil 98 fitted around the piston rod 44 wired to a power source through a switch. When activated, piston return solenoid coil 98 rapidly drives the piston rod 44 and piston 42 away from the cylinder head 24.

The number of cam protrusions 62 on the cam structure 60 preferably can be altered such that the volume of fluid compressed per cam structure 60 revolution can be altered to accommodate any of a wide variety of applications. Where the cam protrusions 62 are cam arms 62, each cam arm 62 preferably has an expanded cam arm mounting end 64 which fits engagingly into any of several cam arm channels 76 having outwardly narrowing arm engaging channel outward ends 78 and extending laterally across the width of and spaced periodically around the cam wheel circumferential surface 72 such that each cam arm 62 is slidably retained within a corresponding cam arm channel 76. See FIGS. 4-6. The cam wheel circumferential surface 72 preferably is sufficiently wide and the cam arm channels 76 therefore sufficiently long that a cam arm 62 can be slid to a first channel end 76a of the given cam arm channel 76 and thus to a first side of the cam wheel circumferential surface 72 to align and register with and abut the piston structure 40, and slid to a second channel end 76b and thus to a second side of the cam wheel circumferential surface 72 to be out of registration with the piston structure 40 during cam structure 60 rotation. The cam arms 62 are retained against sliding out of their respective channels 76 by a retaining clip 77 at the outward-most portion of each channel end 76a and 76b. See FIG. 5. As a result, a selected number of cam arms 62 can be slid into position to register with the piston structure 40 as needed for each given apparatus 10 application.

An outwardly biased spring-loaded retaining protrusion 66 is provided in the a recess in the middle of each cam arm channel end 76a and 76b to obstruct movement of and thus retain the cam arm 62 in the channel 76 at either the first or second channel end 76a or 76b, respectively. See FIGS. 7 and 8. The retaining protrusions 66 are outwardly rounded, and when sufficient lateral force is applied to a given cam arm 62, such as be an electro-magnet 140 described below, the retaining protrusion 66 is forced inwardly into its protrusion recess 66a by the cam arm 62 to become flush with the channel 76 bottom wall, permitting the cam arm 62 to move over the retaining protrusion 66 to the opposing channel end, and then the protrusion 66 is freed to spring outwardly to its initial retaining position.

The cam arms 62 preferably are moved to first or second cam wheel 70 sides by electro magnets 140 mounted to the apparatus framework 100 on opposing sides of the cam wheel 70 adjacent the cam wheel 70 circumferential perimeter. A small air gap is provided between the cam arms 62 and the electro magnets 140 so that cam arms 62 and electro magnets 140 never touch each other. Activation of either electro magnet 140 pulls each immediately adjacent cam arm 62 to the adjacent side of the cam wheel 70. The given electro magnet 140 are activated and deactivated for only a fraction of a second as the cam wheel 70 is rotated by the drive motor 82 so that only selected cam arms 62 are moved to a given side of the cam wheel 70 to provide a desired number of cam arms 62 in registration with the at least one cylinder and piston assembly 20 associated with the given cam wheel 70. Electric power delivered through a manual switch or a computer programmed controller (not shown) activates and deactivates one or the other electro magnet 140 as needed. Many other cam protrusion 62 moving mechanisms are contemplated, and the electro magnets are merely illustrative.

Another variation of the present compressor apparatus 10 includes a plurality of cylinder and piston assemblies 20 positioned and secured to the apparatus framework 100 to extend radially and equidistantly from the cam structure 60. See FIG. 9. The rotating cam protrusion 62 or cam protrusions 62 abut and displace each piston structure 40 in sequence with each cam structure 60 rotation.

Yet another variation of the compression apparatus 10 includes multiple cam structure and cylinder units 200. The cam structures 60 preferably are cam wheels 70 mounted on a common axle and thus driven by a common rotation drive means 180 in the form of a motor. See FIG. 10. Individual clutch means 182 are provided for each cam structure 60 so that only a selected number of the cam structures 60 rotate with the drive means 180.

As an alternative to the one or more cylinder and piston structure assemblies 20, a bellows or other collapsible vessel (not shown) may be provided.

While the invention has been described, disclosed, illustrated and shown in various terms or certain embodiments or modifications which it has assumed in practice, the scope of the invention is not intended to be, nor should it be deemed to be, limited thereby and such other modifications or embodiments as may be suggested by the teachings herein are particularly reserved especially as they fall within the breadth and scope of the claims here appended.