U.S. patent application number 10/706620 was filed with the patent office on 2004-07-29 for portable air compressor/tank device.
Invention is credited to Anderson, Robert W..
Application Number | 20040146408 10/706620 |
Document ID | / |
Family ID | 32738185 |
Filed Date | 2004-07-29 |
United States Patent
Application |
20040146408 |
Kind Code |
A1 |
Anderson, Robert W. |
July 29, 2004 |
Portable air compressor/tank device
Abstract
A portable, low cost air supply device for accumulating and
dispensing compressed air converted from photovoltaic energy. The
device includes one or more photovoltaic cells, a capacitor, an
electronic trigger device, a solenoid, a valve manifold, a
reservoir, and a device for dispensing accumulated air. The
photovoltaic cell(s) charge the small, low cost capacitor. When
saturated, the capacitor is triggered by a solid-state device to
discharge the electrical charge to a solenoid. The energized
solenoid then extends its plunger into a hole in the valve
manifold, compressing air into the manifold. The compressed air
moves past a check valve, and into a storage reservoir. The
solenoid rapidly de-energizes, the plunger retracts, and the
solenoid is now ready for another compression stroke.
Inventors: |
Anderson, Robert W.;
(Wichita Falls, TX) |
Correspondence
Address: |
Mr. Edward J. Timmer
P.O. Box 770
Richland
MI
49083-0770
US
|
Family ID: |
32738185 |
Appl. No.: |
10/706620 |
Filed: |
November 12, 2003 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
60426294 |
Nov 14, 2002 |
|
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Current U.S.
Class: |
417/63 ;
417/411 |
Current CPC
Class: |
F04B 17/006 20130101;
F04B 35/045 20130101; F04B 35/06 20130101 |
Class at
Publication: |
417/063 ;
417/411 |
International
Class: |
F04B 049/00 |
Claims
I claim:
1. A self replenishing, portable air supply device, comprising an
air reservoir tank, one or more photovoltaic cells exterior of the
air reservoir tank, a capacitor for receiving electrical power from
the one or more photovoltaic cells and intermittently discharging
to a solenoid, said solenoid then mechanically compressing air into
the air reservoir tank.
2. Air supply device of claim 1 wherein the capacitor and solenoid
are disposed inside the air reservoir tank.
3. Air supply device of claim 1 including a flashlight disposed on
the air reservoir tank.
4. Air supply device of claim 1 including a self-retracting hose
reel disposed on the air reservoir tank.
5. Air supply device of claim 1 including a hose pressure
indicating gauge with pressure readout disposed on the air
reservoir tank.
6. Air supply device of claim 1 including a manually activated
valve disposed on the air reservoir tank to dispense compressed
air.
7. Air supply device of claim 1 including a connector to secure the
air reservoir tank in a location of use.
8. Air supply device of claim 7 wherein the connector secures the
air supply device on a pick-up truck bed.
9. Air supply device of claim 1 including a one or more
photovoltaic cells for location remote from the air reservoir
tank.
10. A self replenishing, portable air supply device, comprising an
air reservoir tank and one or more photovoltaic cells exterior of
the air reservoir tank to power an air compressor pump which
resides inside the tank.
11. A self replenishing, portable air supply device, comprising an
air reservoir tank, one or more photovoltaic cells exterior of the
air reservoir tank to provide electrical power to a power storage
device, which intermittently provides electrical power to an air
compressor pump.
12. The air supply device of claim 11 wherein the air compressor
pump receives atmospheric air to be compressed via a check valve on
the tank.
13. A method of supplying compressed air, comprising generating
photovoltaic electrical power using light exterior of an air
reservoir tank, storing the electrical power, and intermittently
providing the stored power to an air compressor pump to pressurize
the air reservoir tank.
14. The method of claim 12 including intermittently providing the
stored power to an air compressor pump inside the air reservoir
tank.
15. An air reservoir tank having a manually activated air
dispensing valve.
16. The tank of claim 15 wherein the air dispensing valve is a
pushbutton or a pivotable lever that engages the pushbutton.
17. An air reservoir tank having a flashlight thereon.
18. The tank of claim 17 wherein the flashlight provides a carry
handle for the tank.
19. The tank of claim 17 including a photovoltaic cell to supply
electrical power to charge the flashlight.
20. An air reservoir tank having an air dispensing hose disposed on
a reel that retracts the hose when it is not in use.
21. An air reservoir tank having an air pressure gauge to display
air discharge pressure in the hose.
22. An air reservoir tank having a connector by which the tank can
be held in position.
Description
[0001] This application claims the benefits of provisional
application Serial No. 60/426,294 filed Nov. 14, 2002.
FILED OF THE INVENTION
[0002] The invention relates to a portable, low cost air supply
device for accumulating and dispensing compressed air and powered
by photovoltaic energy.
BACKGROUND OF THE INVENTION
[0003] U.S. Pat. No. 6,367,259 describes an air compressor system
that includes a rotary induction motor, motor control circuitry,
expensive large capacitors, and associated packaging. To date, air
compressor systems that accumulate energy from photovoltaics have
been made up of conglomerations of large static devices, working
together and coordinated by complicated control circuitry and
sensors. These systems are commonly formatted as banks of batteries
or banks of large expensive capacitors. Such storage devices drive
induction motors, which then finally drive compressors.
SUMMARY OF THE INVENTION
[0004] An embodiment of the invention provides an air supply device
and method that accumulate and distribute compressed air without
the use of the large static devices referenced above, that can be
hand carried to the point of use with a size scale easily applied
by the end user, and that eliminates the need for a rotary
induction motor, motor control circuitry, expensive large
capacitors, and associated packaging.
[0005] One illustrative embodiment of the invention involves a
self-replenishing, portable air supply device that includes an air
reservoir tank and one or more photovoltaic cells disposed exterior
of the air reservoir tank. The photovoltaic cell(s) provide(s)
electrical power to a capacitor, which intermittently discharges to
a solenoid, which then mechanically compresses air into the
reservoir tank. In a preferred embodiment of the invention, the
capacitor and solenoid and other related components are located
inside the air reservoir tank.
[0006] The invention optionally provides on the air reservoir tank
one or more of a flashlight, a self-retracting hose reel, a hose
pressure indicating gauge/LCD readout, a manually activated valve
to dispense compressed air, and a connector to secure the portable
reservoir tank in a location of use (i.e. pick-up truck bed). The
invention also envisions optionally providing one or more
remote-mounted photovoltaic cell(s) to allow the air supply device
to serve as an imbedded power unit within a larger system.
[0007] The invention is advantageous to improve the
manufacturability and affordability of a portable air compressor
system by virtue of reduced number of component parts, simplified
integral packaging (placing sensitive components inside the air
reservoir tank), and enabling the use of a very small, and
exponentially cheaper capacitor. Other advantages of the invention
will become more readily apparent from the following description
taken with the following drawings.
DESCRIPTION OF THE DRAWINGS
[0008] FIG. 1 is a schematic view of an air supply device pursuant
to an embodiment of the invention shown for use in inflating a
pick-up truck tire.
[0009] FIG. 2 is a perspective view of an air supply device to an
embodiment of the invention with the air reservoir tank partially
broken away to show the portion of the solenoid pump assembly
residing inside the tank.
[0010] FIG. 2A is an enlarged view of the solenoid pump
assembly.
[0011] FIG. 3 is a sectional view of the solenoid pump assembly and
air reservoir tank wall, depicting the pneumatic circuit. The
circuit board B and capacitor and trigger device thereon are shown
schematically for convenience.
[0012] FIG. 4 is a schematic view showing the photovoltaic cells
and related electronic components relative to the air reservoir
tank, depicting the electrical circuit.
[0013] FIG. 4A is an enlarged view of the electrical trigger device
of FIG. 4.
[0014] FIG. 5 is a perspective view of the air supply device
showing the air reservoir tank having thereon a flashlight, a
self-retracting hose reel, a hose pressure indicating gauge/LCD
readout, a manually activated valve to dispense compressed air, and
a locking lug to secure the portable reservoir tank in locations of
use (i.e. pick-up truck bed).
[0015] FIG. 6 is a perspective view showing the air supply device
having a lug for mounting the air supply device on the bed of
pick-up truck.
[0016] FIG. 7 is an elevational view of the air supply device
having a manual trigger thereon actuated to dispense compressed air
from the air reservoir tank.
[0017] FIG. 7A is an enlarged view of the manual trigger.
DESCRIPTION OF THE INVENTION
[0018] Referring to FIG. 1, an air supply device and method
pursuant to an illustrative embodiment of the invention comprises
an air reservoir tank 1 of conventional fabrication (mild steel, or
aluminum, or plastic composite construction) with an integral carry
handle 21 and attached supporting feet 20 for resting on a
horizontal surface. A pipe nipple 2, FIG. 2 is disposed on and
extends through and into the air reservoir tank 1. A solenoid pump
assembly 19 is configured as a plug received in the pipe nipple 2,
with certain mechanical and electrical circuitry of the solenoid
pump assembly disposed in, and totally enclosed within, the air
reservoir tank 1 as will become apparent below.
[0019] On the exterior surface of tank 1 is/are mounted one or more
photovoltaic cell(s) 14. The energy from the photovoltaic cell(s)
14 is used to charge intermittently solenoid 8 of the solenoid pump
assembly 19 using an electrical circuit shown in FIG. 4. Solenoid 8
and its enclosed plunger 7 reside in the tank 1, FIG. 3, and are
configured to function as an air compressor pump when combined with
valve manifold 11. The solenoid 8 includes a housing with a
threaded or flanged end that is threaded or bolted onto the valve
manifold 11 to join them together as shown in FIG. 3. The
combination of the solenoid 8 and valve manifold 11 is referred to
as the solenoid pump assembly 19. On it's retract stroke, plunger
7, functioning as a piston, draws atmospheric air through the
externally protruding tank valve 3 of the solenoid pump assembly
19. Once the solenoid 8 is energized, plunger 7 advances,
compressing air past spring-biased check valve 13 and into the air
reservoir tank 1. The solenoid 8 can be a commercially available
solenoid, such as Ledex brand size 3EC model available from
Saia-Burgess, Inc.
[0020] The valve manifold 11 has attached, or built integral to it,
devices including 1) a pressure relief valve 6, to prevent tank 1
over pressurization; and 2) a Schrader style tank valve 3,
functioning as an air intake, back flow check valve, and allowing
the filling of tank 1 from an external compressed air source.
Further devices attached or built integral to manifold block 11
include gauge port 5 for mounting a pressure indicator 27 for
gauging discharge pressure; discharge hose connector 12; and
optional discharge valve 10 for manually controlled dispensing of
compressed air. Discharge hose 4 is a flexible tube connected to
discharge hose connector 12. Discharge hose 4 is used for
dispensing compressed air from within tank 1, and can be configured
as a static shape, coiled, or combined with an optional
self-retracting hose reel 23 as shown in FIG. 5.
[0021] An electrical trigger device 16, FIG. 4, is provided and
determines when there is enough electrical charge (energy) stored
in capacitor 15 as an electrical power storage device to energize
solenoid 8. Capacitor 15 will be of low cost and small size,
generally in the 2200 micro Farad size range. The trigger device 16
in its essential embodiment includes a diode 16a and transistor 16b
arranged as shown in FIG. 4A that function together to detect a
fully charged capacitor 15, distribute this stored energy to
solenoid 8, and then reset the circuit so that the energy supplied
by photovoltaic cell(s) 14 can recharge capacitor 15 to repeat the
cycle. The capacitor 15 trigger device 16 and other electrical
components are mounted on a circuit board B located inside the tank
1, FIG. 2. The circuit board is fastened by a U-shaped bracket to
the solenoid housing as shown in FIG. 3. If it is desired to give
an indication external of the tank 1 that the solenoid 8 is
energized, LED 17 can be optionally installed in the circuit as
shown in FIG. 4. A current limiting device 18, which may comprise a
resistor, may be required in the circuit dependent on the current
handling characteristics of photovoltaic cell(s) 14.
[0022] The air supply device also may contain the following
optional features: (a) a pressure switch 28 to shunt excess
electrical potential from photovoltaic cell(s) 14 to the charging
of a rechargeable flashlight 22, FIG. 5, that is disposed on, and
preferably built integral to the carry handle 21 such that the
flashlight body functions as the carry handle for tank 1; (b) an
AC/DC or DC/DC power adapter 29 for powering the air supply device
from an external electrical source; (c) a C-shaped (or other
shaped) strap connector 24, FIG. 6, which is fastened on the air
reservoir tank 1 and which receives and is lockable onto an
elongated male bracket 25 attached to a truck bed, FIG. 6 (or other
structure) when the air supply device is positioned on the truck
bed proximate the front wall thereof so as to prevent the theft of
the device, the bracket 25 having a punched or otherwise-formed
hole to receive a common padlock in a manner that also passes
through the strap connector 24 to lock the connector and the
bracket together; (d) air dispensing valve 10 movable relative to
valve seat 10a and configured as a manually depressed button, or
activated by a lever 30 disposed on a carrying handle 21 attached
to tank 1, FIG. 7, such that when the lever 30 is manually
squeezed, the lever rocks on pivot pin 31 in a manner to depress
air dispensing valve 10, which than opens relative to seat 10a and
supplies compressed air to the discharge hose 4; and (e) a pressure
gauge 26, FIG. 5, for indicating tank air pressure. In an
alternative embodiment of the invention, the discharge hose
connector 12 can be omitted and replaced with hard piping so that
the air supply device can be used as an integral power supply
subcomponent to a larger system. The air reservoir tank 1 may or
may not require customizing to conform within the encompassing
larger system and may or may not require the remote location of the
photovoltaic cells 14 as a power source. Still further, the
solenoid pump assembly 19 alternatively may be mounted or disposed
externally to an air reservoir tank 1 as either a retrofit to an
existing passive air tank, or as an alternative way to construct an
air supply device pursuant to another embodiment of the
invention.
[0023] In operation, photovoltaic cell(s) 14 produce electric
current through exposure to any incident light energy. The electric
charge is stored in capacitor 15. Once capacitor 15 achieves a
charge sufficient enough to overcome the breakdown voltage of the
trigger device 16, the electrical charge is then free to pass
through to the coil of solenoid 8, FIG. 4, to power the solenoid.
An energized solenoid 8 creates an electromagnetic flux passing
through the center of the solenoid 8. Plunger 7, which is located
in the center of solenoid 8, resists the electromagnetic flux,
which causes plunger 7 to thrust rapidly upwards out of solenoid 8.
The air on the leading surface of plunger 7 is compressed through
check valve 13 and into the air reservoir tank 1. The charge in the
capacitor is diminished rapidly and plunger 7 self centers back
into solenoid 8 as the flux relaxes. Gravity helps the plunger 7
retract into the solenoid coil in vertical plunger orientations as
shown in FIG. 3. In other plunger orientations or to speed up
retraction of the plunger 7, a retract spring 32 optionally may be
provided as shown in FIG. 3 to bias the plunger to this end.
Additional plunger retraction speed can be achieved by modifying
the trigger device 16 to not just relax the current flow in
solenoid 8, but to reverse the current flow to thereby forcibly
retract the plunger 7 within the solenoid 8. The withdrawal of
plunger 7 creates a slight low-pressure area within the cavity of
valve manifold 11. This vacuum is relieved by atmospheric air
pressure overcoming the valve stem seating pressure in Schrader
style tank valve 3 and enters the valve manifold 11 internal
cavity. The air supply device is now ready for another cycle. The
frequency of cycles will depend on available light, but will most
likely not exceed 2 cycles per second at maximum sunlight due to
the duty cycle limitations of most commonly commercially available
solenoids.
[0024] Once the air reservoir tank 1 is at the maximum designed
pressure, the backpressure from the compressed air will
counterbalance the thrust force of plunger 7, and the plunger 7
will no longer be able to further compress air into the tank.
Plunger 7 will be stalled, with capacitor 15 continuing to
dissipate energy into solenoid 8. This "self maintaining" mode can
be held indefinitely until gradual leakage reduces air volume to
the point where the plunger 7 can move forward and replace the
escaped air. Alternatively, a pressure switch 28 can detect a full
tank of air, and disconnect the solenoid driving circuit shown in
FIG. 4. The pressure switch 28 can then optionally redirect the
electric potential to charging a flashlight 22, which would be
beneficial for nighttime use of the invention. The flashlight 22
may be built into the carry handle 21 of tank 1 so as to prevent
loss/theft of the light. The flashlight 22 will shine across and
illuminate the pressure indicator 27 at gauge port 5 as well as
illuminate whatever equipment is receiving the compressed air being
dispensed from the air supply device.
[0025] Although certain illustrative embodiments of the invention
have been described herein, those skilled in the art will
appreciate that the invention is not limited thereto and that
changes, modifications and the like can be made thereto without
departing from the spirit and scope of the invention as set forth
in the appended claims.
* * * * *