U.S. patent number 3,571,874 [Application Number 04/828,514] was granted by the patent office on 1971-03-23 for descaling device.
This patent grant is currently assigned to Von Arz AG. Invention is credited to Paul Von Arz.
United States Patent |
3,571,874 |
Von Arz |
March 23, 1971 |
**Please see images for:
( Certificate of Correction ) ** |
DESCALING DEVICE
Abstract
A descaling, derusting, deslagging or metal cleaning device of
the compressed air gun type which is supplied with compressed air
through its handle and such handle is pivotally mounted on the
device and capable of being swung not only into the usual positions
but also into a position at a small angle to the barrel assembly of
the device so as to enable the device to be used in confined and
other places of difficult access.
Inventors: |
Von Arz; Paul (Sissach,
CH) |
Assignee: |
Von Arz AG (Sissach,
CH)
|
Family
ID: |
25252029 |
Appl.
No.: |
04/828,514 |
Filed: |
May 28, 1969 |
Current U.S.
Class: |
29/81.14;
29/81.17; 173/169 |
Current CPC
Class: |
B25F
5/02 (20130101); B08B 7/022 (20130101); Y10T
29/4594 (20150115); B25D 2250/291 (20130101); Y10T
29/4578 (20150115) |
Current International
Class: |
B25F
5/00 (20060101); B25F 5/02 (20060101); B08B
7/02 (20060101); B25D 17/00 (20060101); B25D
17/02 (20060101); B21c 043/00 () |
Field of
Search: |
;29/81 (R)/ ;29/81 (L)/
;227/(N.S-GYC) ;173/168,169 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Guest; Alfred R.
Claims
I claim:
1. In an air-operated descaling device, comprising a barrel
assembly, at least one work engaging tool mounted therein for
limited sliding movement, a compressed air cylinder at the rear end
of the barrel assembly having a piston reciprocable therein by the
air pressure for driving said tool, an air supply passage formed in
said barrel assembly for supplying the air to said cylinder, and an
operating handle for the descaling device having an air passage
therethrough and including a connection at its outer end for an air
supply hose, and the handle also having a manually operated air
control valve, the improvement in combination therewith which
comprises a pivotal mounting between the outer end portion of said
barrel assembly and the inner end of said handle which permits the
handle to be swung about said mounting from a position extending
rearwardly and substantially parallel with the barrel to a position
extending forwardly with respect to the barrel and at a small angle
thereto and means within said pivotal mounting for conveying air
from the passage in said operating handle to said air supply
passage in the barrel assembly.
2. An air-operated descaling device according to claim 1 in which
the pivotal mounting includes a lateral extension projecting from
one side of the barrel assembly, an extension projecting lengthwise
from the inner end of the handle, said extensions having flat
interengaging surfaces and a common crosswise bore, a pivot pin
closely fitting said bore having a head on one end and a nut
threaded on the opposite end for clamping said faces in airtight
swinging engagement, the air passage in said handle communicating
with a circular groove in said handle extension and surrounding the
pivot pin, an air passage in the lateral extension on the barrel
assembly connecting at its inner end with the circular air passage
within the barrel assembly and connecting at its opposite end with
a second circular groove in said lateral extension and surrounding
the pivot pin, and at least one air passage formed in the surface
of said pivot pin and interconnecting said two circular grooves.
Description
BACKGROUND OF THE INVENTION
Field of the invention relates to devices for removing rust, scale,
slag, paint, cement and the like from containers, tanks, boilers,
etc., which are so constructed as to have areas which are difficult
of access, and for removing such materials from grooves and corners
and from bolts and nuts etc.
SUMMARY OF THE INVENTION
The invention relates to a descaling device operated by compressed
air and having a barrel assembly including a main barrel with a
mouthpiece at its outer end and a thimblelike supporting member at
its rear end. Also within its rear end there is a conventional
compressed air cylinder and piston which reciprocates rapidly when
in operation to exert a hammering action against an intermediate or
anvil member which transmits the hammer forces to the work engaging
tool or tools, usually in the form of chisels and especially a
group of small chisels of equal length which engage the work.
The handle having a pistol-type grip and through which the
compressed air is fed to the air cylinder within the barrel
assembly by means of a compressed air hose attached to the outer
end of the handle is pivoted to the thimblelike support for the
barrel assembly by means of a special mounting which permits the
handle to be swung from the rearward position approximately
parallel to the axis of the barrel assembly to a position at right
angles thereto and then forward to a position more or less
approaching parallelism with the barrel assembly. In this position
the tool can be brought with considerably facility and with the use
of only one hand into operative engagement with work areas which
are difficult of access and impossible to clean with customary
devices of this kind. The conveying of the air under pressure
through the handle and into the air cylinder within the barrel
assembly presents a considerably problem, and this problem has been
solved by the present invention by the special mounting which has
been provided and which includes the necessary air passages, these
passages not only serving to properly convey the compressed air,
but also being capable of manufacture according to ordinary methods
of manufacture and without requiring special equipment.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a view of the descaling device in side elevation with
certain parts broken away and shown in central vertical section,
and also showing the handle in different positions shown in broken
lines.
FIG. 2 is a vertical section taken on line 2-2 of FIG. 1;
FIG. 3 is a vertical detailed section taken on line 3-3 of FIG.
2;
FIG. 4 is a similar secton taken on line 4-4 of FIG. 2; and
FIG. 5 is a diagrammatical view showing the application of the
device to an interior surface which is difficult of access.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring first to FIG. 1 the descaling device has a barrel
assembly indicated generally by numeral 7. This assembly includes a
barrel 8 having a thimblelike support 9 at its rear end and a
mouthpiece 10 at its front end. A group or plurality of tools in
the form of chisels 11 project from the mouthpiece 10 into
engagement with the rough surface of a workpiece 12. Chisels of
this type are usually referred to as needles because of their
slender elongated construction and the rear ends of these needles
are shown at 13 and are in engagement with the front end of an
anvil member 14. The needles 13 extend through a plurality of
apertures in a needle holder 15 which slides within barrel 8 and is
urged rearwardly by means of a long helical compression spring 16.
The rear ends of needles 13 usually are provided with small heads
(not shown) to retain them in position in support 15.
In operative relation to the head of anvil 14 is a piston 17, this
piston having a head 18 which operates within the cylinder chamber
19 for the compressed air.
The construction and operation of piston 17 are conventional. That
is to say air under pressure supplied to the space 20 flows through
cross opening 21 in piston 17 and on a longitudinal passage 22 in
the piston to the air chamber 19 when the piston is pushed
backwardly by means of helical spring 16 acting through anvil 14.
Then when the piston 17 is forced forwardly by the air pressure the
air is exhausted through passages 22 and 21 into a space 23 and
exhaust openings 24.
Even though the operation of piston 17 is conventional, the means
for supplying the air under pressure is considered to be novel.
Such means includes a circular groove 25 on the interior of the
thimblelike support 9 and three radial short passages 26 which
connect groove 25 with the space 20 (see FIGS. 1 and 2).
The novel air supply passages also include those in the special
mounting for the handle of the descaling device which is indicated
generally by numeral 27. This handle has a central piston grip
portion 28 and at its outer end there is a connection for a
compressed air hose 29. Near the outer end of handle 27 is a
control valve which is actuated by a pivoted handle 30 and this
valve turns on and shuts off the supply of air from hose 29 to an
air passage (not shown) which extends lengthwise of the handle.
Handle 27 is connected to thimblelike support 9 by means of a
special mounting indicated generally by numeral 31 and shown in
detail in FIGS. 2, 3 and 4. This mounting comprises a lateral
extension 32 which projects from one side of the thimblelike
support 9 and a somewhat similar extension 33 which projects from
the inner end of handle 27. Projection 32 has a flat face 34 which
desirably is on the centerline of member 9, and extension 33 has a
similar flat face 35 which is approximately on the centerline of
handle 27.
A pivot pin 36 extends through a crosswise bore 37 which is common
to the two extensions 32 and 33. Pin 36 is machined to fit closely
the surface of bore 37 and has a head 38 at one end and a nut 39 at
the opposite end which is applied to a screw thread on this end of
the pivot pin. Nut 39 desirably is provided with a cap portion 40
to protect the hands of the operator from the sharp screw thread.
Nut 39 is set up sufficiently to maintain the flat surfaces 34 and
35 on the respective extensions in close sealing engagement with
one another and yet permit the pivoting movement of the handle. A
suitable seal 41 is advantageously arranged in a circular groove in
one of the extensions. A somewhat similar air seal 42 is
advantageously mounted in a circular groove in the cylindrical
surface of bore 37 on the end thereof towards nut 39. Also a seal
43 is placed under the periphery of head 38.
Handle extension 33 is part of a cylindrical member 44 which is
mounted on the inner end of handle 27 in any suitable manner and
has a flat end surface 45 on the portion thereof which is in line
with extension 33.
From this surface 45 a plurality of air passages in the form of
drilled holes 46 extend into the extension 33 and communicate with
a circular groove 47 formed in the portion of bore 37 which is
within extension 33 and spaced somewhat from the flat engaging
surfaces 34 and 35 of the two extensions 32 and 33. The inner ends
of the drilled holes 46 communicate with the air passage previously
referred to but not shown which extends throughout the length of
handle 27.
A circular groove 48 which is similar to groove 47 is similarly
arranged surrounding the portion of bore 37 which is within
extension 32. From circular groove 48 a pair of drilled holes 49
extend angularly upward within extension 32 and the shell of
thimblelike member 9 and communicate with circular groove 25
previously referred to. In order to connect the two circular
grooves 39 and 48 in the respective extensions 33 and 32 a
plurality (three being shown) of lengthwise slots 50 are formed in
the cylindrical surface of pivot pin 36. These may easily be made
by means of a milling cutter.
With this arrangement the desired flow of air from the hose 29 is
provided for in all positions of handle 27. The air from hose 29
flows through the lengthwise passage (not shown) in handle 27
thence to the three drilled holes 46 to the circular groove 47.
From this groove the air flows through the three semicircular
channels 50 to circular groove 48 and thence through the two
drilled holes 49 into circular groove 25 in the thimblelike support
9 and then through the three radial passages 26 to space 20 and the
compressed air cylinder 19.
Referring to FIG. 5, even with handle 27 in the position here shown
the descaling device 7 may be inserted through the opening 51 in
the wall 52 of an otherwise inaccessible chamber. Opening 51 being
in the form of a collar which is welded as indicated at 53 to the
interior of wall 52, the descaling tool can be easily manipulated
to apply the tools 11 thereof in the vicinity of the weld 53 as
well as to other nearby interior surfaces of wall 52.
It will be understood that a single or several larger tools can be
used in place of the needles 11 if desired.
In the manufacture of the device all of the drilled holes can be
drilled without difficulty even those which are angularly placed
such as the holes 49 shown in FIGS. 2 and 4. These holes can be
drilled through the open end of bore 37 at its intersection with
the flat face 34 before the parts are assembled.
* * * * *