U.S. patent number 3,769,753 [Application Number 05/235,293] was granted by the patent office on 1973-11-06 for automatic car sand blaster.
Invention is credited to Henry Fleischer.
United States Patent |
3,769,753 |
Fleischer |
November 6, 1973 |
AUTOMATIC CAR SAND BLASTER
Abstract
An apparatus is disclosed in which a mixture of a highly
volatile chemical solvent and an abrasive is sprayed onto the
surface of an automobile at an obilique angle. The abrasive removes
the paint without chipping and roughs up the surface while the
chemical solvent removes film and dirt thereby enabling the surface
of the automobile to receive a new coat of paint. One embodiment of
the apparatus is disclosed in which spraying devices are mounted
around a platform upon which an automobile may rest. The platform
has a drain for carrying away solvent and abrasive after it runs
off the body of the car. Conveyors are employed to recycle the
still useable materials to reservoirs from which they initially
came.
Inventors: |
Fleischer; Henry (Little Falls,
NJ) |
Family
ID: |
22884898 |
Appl.
No.: |
05/235,293 |
Filed: |
March 16, 1972 |
Related U.S. Patent Documents
|
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
Issue Date |
|
|
68151 |
Aug 31, 1970 |
|
|
|
|
Current U.S.
Class: |
451/87; 451/102;
451/103; 451/91; 451/99 |
Current CPC
Class: |
B24C
3/12 (20130101); B24C 5/04 (20130101); B24C
7/0084 (20130101) |
Current International
Class: |
B24C
5/00 (20060101); B24C 3/12 (20060101); B24C
5/04 (20060101); B24C 3/00 (20060101); B24c
003/12 () |
Field of
Search: |
;51/8,11,12,16
;134/45,123 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Kelly; Donald G.
Assistant Examiner: Goldberg; Howard N.
Parent Case Text
REFERENCE TO OTHER APPLICATIONS
This application is a continuation-in-part of application Serial
No. 68,151, filed August 31, 1970, now abandoned.
Claims
What is claimed is:
1. An apparatus for preparing an object having a painted metal
surface for repainting including:
means for holding said object with said surface in a predetermined
position;
a source of abrasive;
a source of a volatile chemical solvent:
mixing means for mixing abrasive from said source of abrasive and
volatile chemical solvent from said source of chemical solvent to
provide a preparing mixture, said mixing means comprising means for
gravity feeding said abrasive along a path and means for spraying
said volatile solvent across said path; and
directing means for directing a stream of said preparing mixture
onto said surface at any oblique angle, said directing means
comprising a source of compressed air; a nozzle mounted adjacent to
said surface; and means for blowing compressed air from said source
of compressed air through said preparing mixture at said
nozzle.
2. The apparatus as defined in claim 1 also including:
means located below said object for collecting abrasive; and
means for returning collected abrasive from said collecting means
to said source of abrasive for reuse.
3. The apparatus as defined in claim 2 also including a plurality
of sources of abrasive, sources of volatile chemical solvent,
mixing means and directing means located adjacent to said
collecting means.
4. The apparatus as defined in claim 1 in which said directing
means includes a plurality of scoops for catching predetermined
amounts of said preparing mixture; said scoops being arranged
vertically with respect to one another, the higher of said scoops
being larger than the lower of said scoops.
5. The apparatus of claim 1 wherein said means for directing a
stream of said preparing mixture onto said surface at an oblique
angle includes nozzle means causing said preparing mixture to form
a flat V-shaped stream.
6. The apparatus of claim 5 wherein said nozzle means includes a
pair of flat nozzles pivotally connected together to form a
variable V-shape.
7. The apparatus of claim 2 including means for collecting and
recycling evaporated solvent to return it to its source.
Description
FIELD OF THE INVENTION
This invention relates to the preparation of previousy painted
surfaces for repainting and particularly to the preparation of
automobiles for repainting.
BACKGROUND OF THE INVENTION
Many automobiles which are discarded as junk have nothing more
wrong with them than a rusted-out body. In many cases this can be
prevented by a timely repainting of the body of the car. As with
many things a decision to repaint or not to repaint is determined
to a large extent on cost.
Before a car, truck, or other similar items can be repainted, the
old paint must be removed and the metallic surface thereunder
properly cleaned and prepared to receive a fresh coat of paint.
Almost all paint removal and surface preparation of cars is done by
hand by unskilled workers. Therefore, as the minimum cost of labor
increases, the cost of repainting cars is directly affected.
In recent years, it has been exceedingly difficult to obtain
workers to prepare cars for repainting even at increased wages. As
a result, it is not only more expensive than before to have a car
painted, but it is also more difficult to get the job done.
Therefore, it is an object of this invention to provide a machine
for automatically removing paint and dirt from the surface of an
automobile and simultaneously preparing the surface for
repainting.
It is another object of this invention to provide a machine for
automatically preparing a car for repainting which removes the
paint without chipping or gouging the automobile trim.
It is still another object of this invention to provide a machine
for automatically preparing a car for repainting which does not
necessitate a drying operation after use of the machine.
It is a further object of this invention to provide a machine which
may be constructed to accomodate a small automobile repainting
facility or a facility which repaints large numbers of cars and
trucks.
BRIEF DESCRIPTION OF THE INVENTION
With these and other objects in view, the present invention
contemplates a method of and apparatus for removing paint from a
surface of an automobile and preparing the surface to receive a new
coat of paint in which a mixture of abrasive and a volatile
chemical solvent are sprayed under pressure onto the surface at an
oblique angle i.e., less than 45.degree..
In one embodiment sand is gravity fed into a chamber and the
chemical solvent is sprayed across the path of the falling sand to
carry the sand therewith through a nozzle. The nozzle is pivotally
mounted to direct the spray of chemical solvent and sand onto the
surface of the automobile at the oblique angle.
Compressed air is also injected into the chamber to aid the mixture
of chemical solvent and sand being sprayed through the nozzle.
In a further embodiment a plurality of chambers and nozzles are
arranged around a platform to simultaneously spray the surface of a
car. A drain is located in the bottom of the platform to recover
abrasive for reuse and means are provided for separating the
solvent and recovering it for reuse. Hand means are also provided
for finishing the job.
DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a spraying unit constructed to practice the principles
of this invention.
FIG. 2 shows a plurality of spraying units as embodied in FIG. 1
formed in a single element and how the element is interconnected
with additional apparatus to form a machine for stripping paint in
accordance with the teachings of this invention.
FIG. 3 is a side view of a machine employed in practicing the
principles of this invention.
FIG. 4 is a sectional view taken along line 4--4 of FIG. 3 showing
additional features of the machine in FIG. 3.
FIG. 5 shows an alternate embodiment of the spring element shown in
FIG. 2.
FIG. 6 is a perspective view of a hand instrument used with the
present invention for finishing the car.
FIG. 7 is a top view of the instrument of FIG. 6.
FIG. 8 is a sectional view of a car surface repaired using the hand
instrument of FIGS. 6 and 7.
FIG. 9 is a view similar to FIG. 8 of a scratch removed by a prior
art device.
FIG. 10 is an end view of the edge of the nozzle shown in FIGS. 6
and 7.
DETAILED DESCRIPTION OF THE INVENTION
Referring now to FIG. 1, we see a chamber 10 into which sand from a
reservoir 11 gravity fed through a flexible rubber conduit 12. A
highly volatile fluid is pumped from a reservoir 13 by a pump
through a flexible hose 15 across the path of the falling sand. The
stream of pumped fluid is directed at a movably mounted nozzle 16.
A compressor 17 blows air through a flexible hose 18 into the
chamber 10 in a direction similar to the flow of fluid
therethrough. The flow of air and fluid across the path of the sand
is slightly downward so as not to push the sand back up the conduit
12 blocking its downward flow. It should be observed that the mouth
of the conduit 12 is extremely large to aid in the free flow of the
sand therein.
The compressed air and fluid are directed at the nozzle 16 which
has sufficient passing capacity to prevent a backup of sand, air
and fluid. This is desirable so that the chamber 10 does not back
up and become pressurized. By having a separate fluid and air
supply, the volume of fluid can be separately regulated by, for
example, adjusting the speed of the pump 14 while the pressure of
flow can be set by proper adjustment of the compressor 17. The
nozzle 16 can be angularly adjusted with respect to the side of the
chamber 10 so that the angle of incidence of the mixture of sand,
air and fluid upon a surface to be cleaned can be adjusted so that
abrasion rather than chipping occurs.
It should be understood that the term volatile when used with
respect to a fluid, means that the fluid is one which is easily
evaporizable at a temperature below the boiling point of water.
In FIG. 2 we see a cleaning section 19 comprising a plurality of
chambers 10 a through 10e each constructed similarly to the chamber
10. The flexible inlet hoses or conduits for sand 12a through 12e,
air 18a through 18e, and fluid 15a through 15e are shown
schematically as are the nozzles 16a through 16e. Each of these
inlet devices 12a through 12e, 18a through 18e, 15a through 15e are
connected to the cleaning member 19 by quick
connect-connectors.
The cleaning member 19 is pivotally adjustably mounted on a
platform 21 by a swivel pin 22. A tilt angle guage 23 is carried by
the cleaning member 19 so that a tightening screw 24 may be
employed to secure the cleaning member at a desired angular
relationship with respect to the platform 21.
A second cleaning member 26 is pivotally mounted on the first
cleaning member 19 by a swivel pin 27. The second cleaning member
26 has a tilt angle gauge 28 and a tightening screw 29 similar to
the tilt angle gauge 23 and the tightening screw 24 of the first
cleaning member 19.
In each of the chambers 10a through 10e sand is gravity fed through
the conduits 12a through 12e. The conduits 12a through 12e may be
connected to a single sand reservoir such as sand reservoir 11.
Volatile fluid from a fluid reservoir such as fluid reservoir 13 is
pumped to each of the hoses 15a through 15e to be sprayed across
the path of the sand at a downward angle and directed towards the
nozzles 16a through 16e. In a like fashion, air from a compressor
such as compressor 17 is forced through the hoses 18a through 18e
to assist the fluid in carrying the sand to the nozzles. It should
be clear that the details of the sand, air and fluid entry into the
chamber 10 in FIG. 1 is representative of the construction and
entry of materials into the chambers 10a through 10e.
It should be noted that the chambers 10a through 10e are separated
from each other by separating walls 31a through 31d so that each of
the chambers 10a through 10e are selfcontained. In this way, sand,
fluid and air will not pass from chamber to chamber. The nozzles
16a through 16e are located toward the lower extremity of the
chambers 10a through 10e to prevent a buildup of material at the
bottoms thereof.
Referring now to both FIGS. 3 and 4, we see a paint removing and
surface preparing apparatus that could be employed in a commercial
repainting environment. A plurality of cleaning members are
arranged around a platform 21. Each of the cleaning members are
formed from a lower section 19 and an upper section 26. Each of the
sections has a plurality of chambers 10, (not shown), such as the
chambers shown in FIG. 2 and a plurality of nozzles 16. Flexible
hoses and conduits 12, 15 and 18 bring sand from a reservoir 11,
air from a compressor not shown, and a highly volatile fluid from a
reservoir not shown into each of the chambers. The nozzles
designated 16 spray the preparing mixture of sand and the highly
volatile solvent under pressure onto the surface of a truck 32.
As the preparing mixture strikes the surface of the truck 32 at an
oblique angle (i.e., less than 45.degree.), the solvent removes
film and dirt from the surface thereof. The abrasive striking at an
oblique angle removes the paint without chipping. Glass and trim
have been masked so that the impact of the abrasive will not chip
or scrape them. It should be noted that if the angle of the mixture
strikes the surface was greater than 45.degree., there would be a
sand blasting effect on the surface, injuring the same.
The chemical solvent carries away the abrasive and bits of material
removed from the surface of the truck 32, which sits on platform 21
across the top of the platform 21 and through a drain 33. The
solvent which does not run off the surface of the truck 32 will
evaporate quickly, as it is highly volatile so that relatively
little further work must be done on the surface of the truck 32
before repainting is accomplished. The sand carried by the chemical
solvent is brought through the drain to rest on the surface of a
conveyor belt 34. The conveyor belt 34 will bring the abrasive to
rest in piles 35 and 36. The solvent will quickly evaporate and can
then be collected by a fume-hood 60 supported by members 62 and 64
and then condensed to retain the solvent.
A plurality of basket type conveyors 37 scoop up the abrasive from
the piles 35 and 36 and bring them back to the reservoirs 11. It
should be understood that the recirculating systems described above
is employed to bring solvent back to the fluid reservoir 13.
In FIG. 5, we see an alternate embodiment for the cleaning member
19. In this embodiment, the cleaning member 38 is not divided into
compartments as is the cleaning member 19. Instead, sand, air and
the highly volatile solvent is brought in through the quick
connect-connectors attached to the conduit 12 and hoses 15 and 18
causing the mixture to travel down the full length of the member
38. A plurality of scoops 39 through 42 pass through the wall of
the cleaning member 38. The higher scoop 39 is shorter than each of
the succeeding lower scoops 40, 41 and 42. When material strikes
scoop 39, a portion thereof will be sprayed out of the cleaning
member 38 onto a surface at an oblique angle. As less material is
left in the cleaning member 38, a larger scoop will intersect the
path of travel. In this way, a relatively constant stream of
cleaning material will be provided thereby.
A cleaning member 38 can be employed in small painting shops
because it will be considerably less expensive than the cleaning
member 19. Its construction is simplier and requires only one inlet
for sand, one inlet for air, and one inlet for the highly volatile
solvent. In a shop, however, that does a large volume, the cleaning
member 19 would be more suitable.
In FIGS. 6,7 and 10 there is shown a hand nozzle adapted to be
connected to the source of sand, solvent and compressed air
generally designated by the numeral 50. The instrument 50 has two
flat nozzles 52 and 54 hinged at 56 and controlled by a hand
adjusted member 57 to widen or narrow the area covered by the
nozzle. The nozzles 52 and 54 provide a V-shaped pattern.
Thus the instrument 50 is intended to be used to correct scratches,
and other flaws not cleaned by the antomistic apparatus shown in
FIGS. 1-5. Thus the nozzles 52 and 54 interact and are tapered
against one another causing the outflowing mixture to abrade the
surfaces and to taper the painted surface gradually to form a
gradual concave or shallow V shape when the surface is viewed at
cross section as in FIG. 8. This permits scratches, chips, and
nicks to be painted over without any further sanding which now has
to be done manually through the use of machines. No other slurry
streams or combination of chemical abrasive and air will provide
this tapered effect upon a painted surface. The presently known
slurry and sand blast patterns produce a non-tapered effect as
shown in the FIG. 9 cross section view.
This effect requires manual treatment by sanding machines to make a
gradual taper over which fillers and paints can be applied;
otherwise a deep groove or scratch effect will be visible upon the
completion of the paint job.
The following differences are also obvious. The interaction of the
nozzles 52 and 54 makes a double taper multiangle abrading action
upon the treated surfaces. Of course the instrument 50 is operated
at an angle less than 45.degree. to the surface being cleansed.
It should be understood that the above embodiments are merely
illustrative of the principles of this invention and that numerous
others will become obvious to those who have ordinary skill in the
art in light thereof.
* * * * *