U.S. patent number 3,696,825 [Application Number 05/825,748] was granted by the patent office on 1972-10-10 for tank washer.
Invention is credited to Helen G. Guignon, John E. Guignon, John E. Guignon, Jr..
United States Patent |
3,696,825 |
Guignon , et al. |
October 10, 1972 |
TANK WASHER
Abstract
An automatically operable tank washer. A power head drives a
screw through a fixed nut to rotate a nozzle assembly while moving
the nozzle assembly lineally. A linkage causes the nozzle on the
nozzle assembly to swivel during lineal movement of the nozzle
assembly. The power head includes a piston-operated reversible
rotary motor that is controlled by the supply of air to a four-way
automatic reversing valve with spring-loaded mechanical switches.
An automatic throttle valve to vary the speed of the motor in
response to the lineal position of the screw. An automatically
operable cam valve to vary the speed of the motor during each
360.degree. cycle of rotation of the screw. Means for interchanging
screws to vary the pitch of the screw. Means for interchanging cams
to select the patterm of rotational speed variation.
Inventors: |
Guignon; John E. (St. Louis,
MO), Guignon; Helen G. (St. Louis, MO), Guignon, Jr.;
John E. (Alexandria, VA) |
Family
ID: |
25244831 |
Appl.
No.: |
05/825,748 |
Filed: |
May 19, 1969 |
Current U.S.
Class: |
134/167R |
Current CPC
Class: |
B08B
9/093 (20130101); B01J 19/0073 (20130101); B01J
19/0053 (20130101); B01J 19/0066 (20130101) |
Current International
Class: |
B01J
19/00 (20060101); B08B 9/093 (20060101); B08B
9/08 (20060101); B08b 009/08 () |
Field of
Search: |
;134/167R,168,180,181
;239/227 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Allen; Edward C.
Claims
What is claimed is:
1. A tank washer comprising a housing, a pipe slidably supported by
the housing, a nozzle assembly connected to the pipe, means to
connect the tank washer to a tank to be cleaned with the nozzle
assembly and at least part of the pipe projecting within the tank,
means to reciprocate the pipe relative to the housing, means to
rotate the pipe relative to the housing, thereby reciprocating the
nozzle assembly and rotating the nozzle assembly, the nozzle
assembly comprising at least one nozzle having a nozzle outlet
orifice and liquid passages communicating the outlet orifice with
the interior of the pipe, means for mounting the nozzle for
rotation about an axis perpendicular to the axis of the pipe, means
to cause rotation of the nozzle about said perpendicular axis in
response to lineal movement of the pipe, and means to supply liquid
to the interior of the pipe and to transmit the liquid through the
nozzle liquid passages to the nozzle outlet orifice, whereby the
pipe acts both to supply liquid and transmit reciprocating and
rotating motion to the nozzle, the rotating motion being about two
axes.
2. The tank washer of claim 1 including means to vary the lineal
speed of reciprocation of the pipe and therefore of the nozzle
assembly.
3. The tank washer of claim 1 including means to vary the speed of
rotation of the pipe and therefore of the nozzle assembly during
each 360.degree. cycle of rotation.
4. The tank washer of claim 1 wherein the means to reciprocate the
pipe and to rotate the pipe comprises a reversible rotary motor, a
threaded rod connected to the output shaft of the motor, a fixed
nut mounted within the housing, the threaded rod being threaded
through the fixed nut so that, as the rod is rotated by the motor,
it is driven lineally as it threads through the fixed nut.
5. The tank washer of claim 4 wherein the motor is a
piston-operated air motor having a rotary output shaft.
6. The tank washer of claim 5 including means to adjust the supply
of air to the air motor to vary the rate of rotation of the motor
output shaft in response to the lineal position of the threaded
rod, and means to vary the supply of air to the air motor in a
predetermined program throughout each 360.degree. cycle of rotation
of the motor output shaft.
7. The tank washer of claim 5 including a four-way reversing valve
having a spring-loaded actuating element for reversing the supply
of air to the air motor to reverse operation of the air motor.
8. The tank washer of claim 4 including means to interchange
threaded rods for selecting the pitch of the threads thereon.
9. The tank washer of claim 5 wherein the means to vary the supply
of air to the air motor in each 360.degree. cycle of rotation of
the threaded rod comprises a cam having a cam surface, a cam valve
in the air supply line responsive to variations in the cam surface,
and means to mount the cam for replacement by other cams having
other cam surface configurations.
10. The tank washer of claim 4 including means to mount the fixed
nut for replacement by other fixed nuts, and means to prevent
rotation of the fixed nut in its mounting.
11. The tank washer of claim 1 wherein the nozzle assembly has a
plurality of nozzles.
12. The tank washer of claim 11 wherein each nozzle comprises a
tubular passage leading to a converging wall surrounding the nozzle
outlet orifice, and a stream straightener disk positioned within
the tubular passage adjacent the converging wall, the stream
straightener disk having a plurality of passages through it
parallel to the direction of flow of liquid through the nozzle,
each of the plurality of passages being of round cross-section.
13. The tank washer of claim 1 wherein the means to cause rotation
of the nozzle in response to lineal movement of the pipe comprises
a linkage of fixed length connected between the nozzle and the
housing, the nozzle having a pivotal connection to the linkage, a
track and follower connection between the housing and the linkage
to permit the linkage to revolve around the housing as the pipe is
rotated, and means to hold the follower in contact with the
track.
14. The tank washer of claim 1 including means for automatically
closing the nozzle in response to rotation of the nozzle to a
predetermined position upon lineal movement of the pipe.
15. The tank washer of claim 14 wherein the automatic closing means
comprises spring-biased stops supported by the housing and
positioned to block the nozzle outlet orifice upon rotation of the
nozzle to the aforesaid predetermined position.
16. The tank washer of claim 1 wherein there are a plurality of
nozzles having nozzle outlets, a cylindrical manifold for
supporting the nozzles, a cylinder, a plurality of slots in the
cylinder the nozzles being aligned with the slots in the cylinder,
the manifold being rotatable in response to lineal movement of the
pipe to move the nozzle orifices relative to the slots for spraying
liquid through the slots.
17. The tank washer of claim 16 wherein the manifold is rotatable
to a position at which the nozzles are moved beyond the slots and
are blocked from spraying liquid by the cylinder.
18. The tank washer of claim 1 wherein the nozzle comprises a valve
housing having an outlet orifice, a valve member movable toward and
away from the outlet orifice, a piston connected to the valve, a
spring to bias the piston in a direction to move the valve member
into a position blocking the outlet orifice, a liquid inlet to the
valve housing, the liquid inlet communicating with the interior of
the pipe, a face on the piston exposed to liquid in the liquid
inlet and positioned to respond to liquid pressure to move the
valve member away from the outlet orifice, the total liquid force
on the said piston face being greater than the spring force.
Description
BRIEF DESCRIPTION OF THE INVENTION
This invention provides a fast-operating automatic tank washer. The
tank washer may be used for cleaning any kind of tank and it is
especially suitable for cleaning chemical reactor tanks where speed
of cleaning is an important economic consideration, freedom from
personal contact with the contaminants in the tank is a health
consideration, and freedom from any possibility of electrical
arcing because of the possible presence of explosive gases is a
safety consideration.
In cleaning such chemical reactor tanks, the tank washer is first
operated through its cycle to spray clear water over the interior
surface of the tank to remove up to 90 percent of the sludge from
the walls of the tank. After the wash water is drained from the
tank, the tank washer is again operated through its cycle to spray
solvent against the interior surfaces of the tank to remove all the
remaining sludge and foreign matter from the inner surface walls of
the tank. Then the solvent containing foreign matter in the tank is
circulated again through the tank washer, but this time the solvent
is mixed with water so that, when the sprayed mixture of solvent
and water is collected within the tank, the solvent and water can
be removed and delivered to a suitable conventional press for
separation and recovery of the solvent. Finally, the tank washer is
again operated through its cycle to spray clear rinse water against
the interior surfaces of the tank to remove any remaining solvent
and the clear rinse water is drained from the now clean tank.
In brief, the tank washer has a power head that comprises a
cylindrical housing. A reversible piston-operated rotary motor is
slidably mounted within the housing. A threaded rod or screw is
connected to the outlet shaft of the motor, and a pipe is connected
to the lower end of the threaded rod. The threaded rod is threaded
through a fixed nut, so that, as the rod is rotated by the motor,
it is driven upwardly or downwardly as it turns through the fixed
nut. The pipe slides through sealed bearings in a liquid outer
jacket, and openings through the side wall of the pipe permit
liquid admitted to the outer jacket to flow into the pipe. A nozzle
assembly is connected to the lower end of the pipe. The nozzle
assembly comprises a nozzle manifold that is rotatably mounted on a
horizontal axis and has a plurality of nozzles projecting from it.
A lever assembly is connected between the nozzles and a collar on
the liquid outer jacket, so that, as the pipe moves linearly
downwardly or upwardly, the lever assembly forces the nozzles to
oscillate. There are spring-loaded closure valves for automatically
blocking the nozzle outlet orifices when the nozzles are directed
in predetermined directions.
The nozzles incorporate a disc insert that has a plurality of
passages of circular cross section that act as stream straighteners
to remove turbulence of the liquid prior to its flowing through the
nozzle outlets.
An automatic throttle valve is provided for varying the supply of
air to the air motor in response to the lineal position of the rod
and pipe. Thus, lineal speed of movement of the nozzle assembly is
automatically varied by the automatic throttling valve. Also, the
air motor is automatically reversed by an automatically operating
four-way reversing valve. This four-way reversing valve has
mechanical switches that are actuated by actuator plates which move
with movements of the threaded rod. Electrical switches that might
produce arcing are eliminated.
Variations in speed of the motor during each 360.degree. cycle of
rotation are provided by a cam valve. The cam valve operates with a
cam follower that follows a cam surface. The cam surface is on an
interchangeable cam to enable selection of an appropriate cam
surface configuration for different tank-cleaning projects. The
variable speed produced by the cam operated valve is superposed on
the variable lineal speed produced by the automatic throttling
valve.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side elevation view of the tank washer.
FIG. 2 is an enlarged view in longitudinal medial section through
the upper portion of the tank washer.
FIG. 3 is a fragmentary view in longitudinal medial section through
the lower portion of the tank washer. FIGS. 2 and 3 illustrate the
screw and pipe in their uppermost positions.
FIG. 4 is a view in section taken along the line 4--4 of FIG.
2.
FIG. 5 is a further enlarged fragmentary view in longitudinal
medial section showing the upper bearing assembly.
FIG. 6 is an enlarged view in longitudinal medial section showing
the lower bearing assembly.
FIG. 7 is a fragmentary elevation view of the lower portion of the
tank washer as viewed from the right of FIG. 1.
FIG. 8 is a view in section taken along the line 8--8 of FIG.
7.
FIG. 9 is a view in section taken along the line 9--9 of FIG.
8.
FIG. 10 is a side elevation view of the snap action four-way valve
actuated to one condition, as viewed in FIG. 2 if the throttle
valve were removed.
FIG. 11 is a side elevation view of the snap action four-way valve
actuated to another condition.
FIG. 12 is a front elevation view of an alternative nozzle manifold
with the nozzles open.
FIG. 13 is a side elevation view of the nozzle manifold in the open
nozzle condition.
FIG. 14 is a front elevation view of the nozzle manifold with the
nozzles closed.
FIG. 15 is a side elevation view of the nozzle manifold in the
closed-nozzle condition.
FIG. 16 is a view in section taken along the line 16--16 of FIG.
13.
FIG. 17 is a view in section taken along the line 17--17 of FIG.
12.
FIG. 18 is a view in section taken along the line 18--18 of FIG.
12.
FIG. 19 is a view in section taken along the line 19--19 of FIG.
12.
FIG. 20 is a view in section taken along the line 20--20 of FIG.
14.
FIG. 21 is a view in section taken along the line 21--21 of FIG.
14.
FIG. 22 is a view in section taken along the line 22--22 of FIG.
14.
FIG. 23 is a fragmentary elevation view in section showing a
modified form of nozzle.
DETAILED DESCRIPTION OF THE INVENTION
The tank washer 20 has a housing 21 that is in the form of a
cylinder having an upper end 22 and a lower end 23. A reversible,
piston-operated, rotary air motor 24 is slidably mounted in the
upper end of the cylindrical housing 21. A plate 25 is fastened to
the lower side of the motor 24 by a plurality of bolts 26. A
central opening 27 in the plate 25 accommodates the rotatable
output shaft 28 of the motor 24.
A rod 31 extends below the motor output shaft 28. The rod 31 is
releasibly connected to the output shaft 28 by a collar 32 that has
one bolt 33 threaded against the motor output shaft 28 and another
bolt 34 threaded through the rod 31. A large cam 35 is threaded
onto the rod 31 and is locked in place by a key 36. The cam 35 has
an eccentric cam surface 37 as shown in FIG. 4 and has a function
that will be described in more detail hereinafter. The cam 35 is
removable so that other cams having other cam surface
configurations may be substituted.
Another threaded rod 38 is connected to the rod 31 by a collar 39
that has one bolt 40 extending through the rod 31 and another bolt
41 extending through the rod 38. The rod 38 is threaded through a
stationary nut 42 that is removably fixed in place within a split
plate 43 by a key 44. The split plate 43 is mounted within the
housing 21 by a plurality of bolts 45. The lower end of the rod 38
is connected to the upper end of a pipe 46 that has a block 47
threaded into its upper end to act as a water-tight seal. A bolt 48
is threaded through the upper end of the pipe 46, the block 47 and
the rod 38 to connect the rod 38 to the pipe 46.
A cylindrical liquid outer jacket 50 is connected below the housing
21. The outer jacket 50 has an upper end 51 and a lower end 52. A
plurality of sleeves 54 are positioned between the housing 21 and
the outer jacket 50 with a bolt 55 extending through each sleeve. A
nut 56 is threaded onto the end of each bolt 55. A liquid inlet
pipe 57 leads to the outer jacket 50. The liquid inlet pipe 57 has
an annular flange 58 welded to its outer end to enable connection
to a supply pipe that delivers water with or without various
cleaning compounds.
The pipe 46 extends through the outer jacket 50 and is slidable
between two bearing members 60 and 61. As shown in FIG. 5, the
upper bearing member comprises two rings 62 and 63 positioned
between an annular shoulder 64 projecting inwardly from the inner
surface of the outer jacket 50 and the nut 56. The rings 62 and 63
are vertically spaced from one another, and a tube 65 is connected
through the side wall of the outer jacket 50 and leads from a
source of compressed air (not shown) to deliver compressed air to
the space between the bearing rings 62 and 63 at a pressure of
approximately 5 psi above the wash or tank pressure. A pair of
O-rings 66 and 67 in the bearing ring 62 provide seals against the
outer jacket 50 and the pipe 46 respectively. A pair of O-rings 68
and 69 in the bearing ring 63 provide seals against the pipe 46 and
the outer jacket 50 respectively. The high pressure air supplied
through the tube 65 is further assurance that no liquid will flow
from within the outer jacket 50 past the bearing member 60.
As shown in FIG. 6, the lower bearing member 61 comprises a bearing
ring 72 that is tightly fitted within the lower end of the outer
jacket 50 and is positioned against an annular shoulder 73. A
plurality of bolts 74 extends through a bearing collar 75 which
will be described more fully hereinafter. Nuts 76 on the inner ends
of the bolts 74 bear against the lower side of the bearing ring 72.
A pair of O-rings 77 and 78 in the bearing ring 72 provide
liquid-tight seals against the pipe 46 and the water jacket 50
respectively.
The pipe 46 has openings 80 in its side wall to permit liquid
flowing from the liquid inlet pipe 57 to flow into the pipe 46. The
lower end of the pipe 46 is bolted to the header 81 that has a
horizontally oriented cylindrical sleeve 82, both of which
constitute the housing parts of a nozzle assembly 83.
A cylindrical nozzle manifold 84 is rotatable within the sleeve 82.
End caps 85 are fastened to the outer ends of the nozzle manifold
84 by a plurality of bolts 86. The nozzle manifold 84 has openings
87 through its side wall to permit liquid communication from the
pipe 46 to the nozzle manifold 84 regardless of the rotated
position of the nozzle manifold 84. To one side of the sleeve 82, a
pair of nozzles 88 and 89 are mounted in the nozzle manifold 84 and
project outwardly therefrom in opposite directions. To the other
side of the sleeve 82, two other nozzles 90 and 91 are mounted in
the nozzle manifold 84 and project outwardly in opposite
directions. The nozzles 88 and 90 are parallel to one another and
the nozzles 89 and 91 are parallel to one another. The nozzles 88
through 91 are identically constructed and, as shown in FIGS. 8 and
9, each nozzle has an internal passage 93 communicating with the
interior of the nozzle manifold 84. The outer end 94 of the passage
93 is converging and leads to a relatively small opening 95. A plug
96 is pressed within the passage 93. The plug 96 has a plurality of
small diameter passages 97 of round cross-section through it.
Each of the nozzles 89 and 91 is slidable within a sleeve 100 that
extends from one side of a plate 101. Each plate 101 is pivotally
mounted on a bolt 102 between a pair of nuts 103 and 104 that act
as lateral guides. The bolt 102 is mounted on its center in a block
105. The block 105 extends upwardly between a pair of guide ears
106 that are on a bracket 107 welded to the header 81. A threaded
rod 109 is threaded into the block 105 and locked in place by a nut
110. The upper end of the rod 109 is threaded into a bearing
support 111 and locked in place by a nut 112. A ball bearing 113 is
mounted on a stud 114 that extends at right angles from the bearing
support 111 and is held in place by a pin 115, as shown in FIG.
3.
The bearing 75 already mentioned as being connected to the lower
end of the water casing 50, has an annular groove 117 that receives
the ball bearing 113. The annular groove 117 has upper and lower
walls 118 and 119 against which the ball bearing 113 rides. A metal
or plastic strap 120 is fastened at its ends to the pin and extends
within the groove 117 to hold the ball bearing 113 within the
annular groove 117 while permitting the ball bearing 113 to pivot
or rock.
A horizontal plate 125 is welded to the pipe 46 above the nozzles
88 and 90. A bolt 126 is threaded through the plate 125 with a nut
127 locking the bolt 126 in place. The bolt 126 clamps a V-shaped
leaf spring 128 in a position to block the nozzle outlet 95 in the
nozzle 88 when the nozzle 88 is swung just past the vertical
position illustrated in FIG. 8. Another bolt 129 is threaded
through the plate 125 and is locked in place by a nut 130. A
V-shaped leaf spring 131 is clamped by the bolt 129 in a position
to block the nozzle opening 95 in the nozzle 90 when the nozzle 90
is moved just past a vertical position.
A pair of plates 132 and 133 are welded to the underside of the
sleeve 82, as illustrated in FIGS. 7 and 8. A block 134 between the
plates 132 and 133, to which the plates 132 and 133 are connected
by bolts 135, holds the plates 132 and 133 rigidly in place. The
plate 132 has a horizontal extension 136. A bolt 137 is threaded
through the horizontal extension 136 and is held in place by a nut
138. The bolt 137 attaches a V-shaped leaf spring 139 in a position
to block the nozzle opening 95 in the nozzle 89 when the nozzle 89
is moved just past the vertical position illustrated in FIG. 8. The
plate 133 has a horizontal extension 140. A bolt 141 is threaded
through the plate extension 140 and is held in place by a nut 142.
The bolt 137 attaches a V-shaped leaf spring 143 in a position to
block the nozzle opening 95 in the nozzle 91 when the nozzle 91 is
moved just beyond the vertical position. The ends of the nozzles
88-91 have tapers 144 to facilitate depression of the adjacent leaf
springs 128, 131, 139 and 143 upon return of the nozzles into
contact with the leaf springs.
The drive control for the motor 24 includes a four-way reversing
valve 145 having a valve housing 146 (see FIGS. 10 and 11) mounted
on a bracket 147 that is bolted to the housing 21. The valve 145
has a pair of outlet hoses 148 and 149 that alternately communicate
with an inlet hose 150 according to the position of an internal
slide (not shown) in a manner known to the art. A pair of pins 151
and 152 connected to opposite ends of the slide project from
opposite sides of the valve housing 146. The pins 151 and 152 are
in the paths of movement of two plates 153 and 154. The plates 153
and 154 are mounted on a common rod 155 that is slidable within the
housing 146 between the position illustrated in FIG. 10 and the
position illustrated in FIG. 11. The position of the rod 155, and
therefore of the plates 153 and 154, is controlled by the position
of a toggle lever 156. The toggle lever 156 is spring-loaded by a
tension spring 157 mounted between the toggle lever 156 and the
housing 146. The spring 157 biases the toggle lever 156 toward
either the position shown in FIG. 10 or the position shown in FIG.
11 to provide a snap action.
A pair of plates 158 and 159 for actuating the toggle lever 156 are
threaded to adjustable positions on a threaded rod 160. At its
upper end, the rod 160 is connected to an extension 161 of the
plate 25 that slides with the motor 24. The extension 161 projects
through a vertical slot 162 in the housing 21. In place of the
double switch valve shown, a four-way, two-position valve, with
snap action operator and no sliding or rotating seals is used as an
alternate to the valve shown.
An automatic throttle valve 163 has a housing 164 that is mounted
by suitable means on the side of the four-way reversing valve 145.
A cable 165 that is connected between the plate extension 161 and
the housing 164 is wound about a stem on the automatic throttle
valve 163.
The two air outlet hoses 148 and 149 lead from the four-way
reversing valve 145 to the motor 24. Air in one hose 148 causes the
piston-type rotary motor 24 to be operated in one direction,
whereas, air supplied through the other hose 149 causes the motor
24 to be operated in the reverse direction. The inlet hose 150 to
the four-way reversing valve 145 is connected to the outlet (not
shown) of the throttle valve housing 164. Inlet air to the throttle
valve is supplied by a hose 166.
The hose 166 leads from two branch tubes 167 and 168. Air is
delivered to the two branch tubes 167 and 168 by another air tube
169 connected to a suitable source of compressed air (not shown). A
manually adjustable needle valve 170 is connected in the branch
tube 168 for setting a rate of flow through the tube 168. A
normally closed cam valve 171 is connected in the tube 167. The cam
valve 171 is operated by a cam follower 172 that rides on the cam
surface 37 of the large cam 35, the cam follower 172 projecting
through a slot 173 in the side of the housing 21.
The tank washer 20 is adapted to be mounted over a tank 175. For
this purpose, a plate 176 is welded to the water casing 50 to
enable the tank washer 20 to be fastened by bolts 177 extending
through the plate 176 and threaded into the flanged collar 178 that
surrounds the access opening 179 of the tank 175.
OPERATION
A threaded rod 38 and a cam 35 are selected for most effective
cleaning of the particular tank 175. Different rods 38 having
different thread pitches are available. These different thread
pitches provide selected variation of the spacing between tracks of
liquid streams emitting from the nozzles 88 through 91 and of the
total time required for lineal travel of the threaded rod 38
between the limits defined by the positions of the switch actuator
plates 151 and 152. The selection of a cam 35 is to supply a
desired camming surface configuration for the most effective speed
variation through each rotation of the threaded rod 38, according
to the tank 175 being cleaned.
The rod 38 is replaced by simply removing the bolts 41 and 48 to
disconnect the previously installed rod and removing the bolts 45
to release the split plate 43 and the fixed nut 42. The cam 35 is
replaced by removing the bolts 34 and 40 to permit removal of the
rod 31. Then, the motor 24 can be slid from the housing 21 and the
selected cam 35 and rod 38 placed in position, followed by
re-installing the various bolts.
The length of travel of the rod 38 is adjusted by adjusting the
positions of the switch actuator plates 158 and 159 on the threaded
rod 161. This is done by simply turning the plates 158 and 159 to
the selected positions. Ordinarily, the travel of the rod 38 is
adjusted to between 3 and 5 inches. Now, with the tank washer 20
installed by threading the bolts 177 through the plate 176 and into
the collar 178, and with the air hose 169 connected to a suitable
source of compressed air and the liquid inlet pipe 57 connected to
a suitable source of liquid, the tank washer 20 is ready for
operation.
Operation begins with the threaded rod 38 in its uppermost
position. This means that the pipe 46 connected to the rod 38 is in
its uppermost position so the nozzle manifold 84 is in its
uppermost position. This uppermost position is established as one
that will pivot the plates 101 upwardly slightly because of the
engagement of the collars 100 with the nozzles 89 and 91. This
slight upward pivoting of the plates 101 swings the nozzles 88
through 91 slightly past vertical positions and into engagement
with the leaf springs 128, 131, 139 and 143 to positions in which
these leaf springs respectively block the nozzle orifices 95 of the
nozzles 88 through 91. Thus, when the tank washer 20 is not
operating and when it is first started, all the nozzles are
automatically blocked even though liquid is being supplied through
the liquid inlet pipe 57 and thence through the openings 80 into
the pipe 46 and through one of the openings 87 in the nozzle
manifold 84 to be distributed to the nozzles 88 through 91. This
automatic closing of the nozzle orifices 95 is particularly
important in applications for which the tank washer is permanently
installed in a tank. With the nozzle orifices 95 closed, none of
the product handled by the tank 175 can flow into the nozzle
orifices 95.
As air is supplied through the air inlet tube 169, the air flows
through the branch tube 168 and through the tube 166 to the
four-way reversing valve 145. Since the tank washer 20 is being
started with the threaded rod 38 and the other components in their
uppermost positions, the toggle 156 and the actuator plate 153 will
be in the positions shown in FIG. 11, depressing the pin 151 and
actuating the valve to cause air to be supplied through the air
tube 148 to the motor 24 and to block the supply of air through the
air tube 149. The supply of air through the tube 148 operates the
motor 24 to rotate the threaded rod 38 in a direction that drives
it downwardly as it rotates within the stationary nut 42. On this
initial operation of the motor 24, the automatic throttling valve
163 will be in its full open position because it is desired to
rotate the threaded rod 38 at the maximum speed when the nozzles 88
through 91 are in their generally vertical positions and to
gradually reduce the rotational speed of the rod 38 as the nozzles
88-91 swing toward generally horizontal positions.
As the motor 24 operates to rotate the threaded rod 38, and the
threaded rod 38 thereby moves downwardly as it threads itself
through the stationary nut 42, the pipe 46 also moves downwardly.
Since the assembly of the block 105, the rod 109, and the bearing
support 111 is of fixed length, the initial downward movement of
the pipe 46 causes the plates 101 to pivot counter clockwise as
viewed in FIG. 3. As soon as these plates have pivoted to
horizontal positions, swinging the nozzles 88-91 to vertical
positions, the nozzle orifices 95 are moved clear of the leaf
springs 128, 131, 139 and 143. Therefore, the liquid being supplied
to the nozzles 88-91 flows through the stream straighteners 97 and
out the nozzle orifices 95 against the inner wall of the tank 175.
Of course, as the threaded rod 38 is rotating it rotates the pipe
46 and therefore rotates the nozzle manifold 84 to direct these
initial streams of liquid sprayed from the nozzles 88-91 in very
small circles.
Since the initial circles traversed by the liquid streams are very
small, relatively short paths are covered in each 360.degree.
rotation cycle of the rod 38. Hence, the automatic throttle valve
163 is set to admit the maximum air to the tube 148 and operate the
motor 24 at maximum speed. As the motor 24 continues to rotate the
rod, the rod moves further downwardly, moving the pipe 46 further
downwardly and swinging the plates 101 further in counter clockwise
directions as viewed in FIG. 3. This swings the nozzles 88-91
further in counter clockwise directions as viewed in FIG. 8 as they
gradually move from the vertical positions there illustrated toward
horizontal positions. As the nozzles 88 through 91 are gradually
swung from the vertical positions, the circular areas of
impingement of the liquid streams emitting from the nozzles 88
through 91 gradually enlarge. However, at the same time, the
automatic throttle valve 163, as actuated by the winding of the
cable 165 on its stem, gradually reduces the speed of rotation of
the rod 38 as caused by the motor 24. This variation in speed thus
compensates for the gradually increasing circumference of the
circular areas of impingement of the liquid streams flowing from
the nozzles 88 through 91.
As the motor output shaft 28 rotates, it rotates the cam 35. When
the cam rotates, its cam surface 37 also rotates. As the cam
surface 37 rotates, the cam follower 172 is moved away from and
then toward the axis of the threaded rod 38. As the cam follower
172 moves away from the axis of the rod 38, it opens the cam valve
171, permitting some of the supplied air from the tube 169 to flow
through the branch tube 167. This additional air combines with the
air flowing from the branch tube 168 in the tube 166 to increase
the total rate of air flow to the throttle valve 163. When the cam
valve 171 thus increases the rate of air flow, the speed of
rotation of the motor 24 is increased. In this manner, the speed of
rotation of the motor 24 can be varied in each 360.degree. cycle of
rotation. The cam valve 171 causes the rod 38 to be rotated
relatively rapidly when the nozzles 88 through 91 are sweeping past
those portions of the tank 175 that are relatively close to them
and to be rotated relatively slowly when the nozzles 88 through 91
are sweeping past areas of the tank 175 relatively far from then,
such as the more remote corners. The cam valve 171 repeats the
variations of speed of the motor 24 for each rotation of its output
shaft 28 as established by the configuration of the cam surface
35.
When the threaded rod 38 has been rotated until it has threaded its
way through the stationary nut 42 to its lowermost position, at
which time the nozzles 88 through 91 will have been moved to or
beyond horizontal positions, the actuator plate 158 will have been
moved downwardly with the rod 160 and the plate 25 connected to the
slidably mounted motor 24. As the plate 158 moves downwardly, it
moves the toggle 156 downwardly and finally to and past center.
Because of the spring 157, the toggle 156 cannot stop on center,
but will snap positively to the "down" position shown in FIG. 10.
This shifts the rod 155 and the plates 153 and 154 upwardly,
releasing the pin 151 and depressing the pin 152 to reverse the
valve. Now, air is admitted through the air tube 149 to the motor
24 but air is blocked from flowing through the tube 148 to the
motor. This reverses the motor 24, reversing the direction of
rotation of its output shaft 28 and reversing the direction of
rotation of the threaded rod 38. Now, therefore, the threaded rod
38 threads through the nut 42 and is driven upwardly, reversing all
of the functions and operations previously described. As the rod 38
moves upwardly, the automatic throttling valve 163 gradually
increases the speed of the motor 24, subject to the variations
produced by the cam valve 171 during each rotation of the motor
output shaft 28. Finally, the rod 38 again moves to its extreme
upper position and the nozzles 88 through 91 are rotated to and
past their vertical position until their orifices 95 are again
opposite the blocking leaf springs 128, 131, 139 and 143, and the
tank washer is then stopped.
FIGS. 12 through 22 illustrate a modified nozzle assembly 185 that
may be substituted for the nozzle assembly 83. The nozzle assembly
185 has a header 186 comprising a vertical sleeve 187 that is
fastened to the pipe 46 by a bolt 188, with a horizontal cylinder
189 formed at the lower end of the vertical connecting sleeve 187.
The cylinder 189 has a plurality of vertical slots 190, 191, 192,
193, 194, 195, 196, 197, 198, 199, 200 and 201 through its side
that communicate with the interior 202 of the cylinder 189. The
slots 190-195 are in one V-row and the slots 196-201 are in another
parallel V-row. Each slot extends around approximately a 45.degree.
arc of the circumference of the cylinder 189. This, with the
motions to be described, provides complete spray coverage of every
point on the interior of a tank to be cleaned.
A cylindrical manifold 204 is rotatable within the cylinder 189.
(See FIGS. 17 through 21.) The manifold 204 has a hollow interior
205 and has an opening 206 through its upper side to maintain
communication between the pipe 46 and the hollow interior 205 of
the manifold 204.
A pair of plates 208 and 209 are mounted on the ends of the
manifold 204 by bolts 210. The plates 208 and 209 are bent inwardly
to provide extensions 211 and 212 respectively that are fastened by
nuts 213 onto a bolt 214. The bolt 214 is pivotally supported in
the block 105 that has already been described. As the pipe 46 moves
vertically, the plate extensions 211 and 212 pivot on the bolt 214
to swing through approximately a 45.degree. arc between the
positions illustrated in FIG. 13 and FIG. 15. The swivel mounting
of the ball 113 within the annular groove or track 117 permits the
block 105 to swing inwardly as necessary to accommodate the pivotal
movement of the plates 208 and 209.
A plurality of nozzle units are mounted in the manifold 204. As
FIG. 17 illustrates, two nozzle units 218 and 219 are mounted in
the manifold in line with the slots 190 and 196 respectively. The
inner ends 220 and 221 of the nozzle units 218 and 219 communicate
with the interior 205 of the manifold for receiving liquid from
within the manifold. The outer ends 222 and 223 (see FIG. 12) of
the nozzle units 218 and 219 have liquid outlets. These nozzle
units 218 and 219 are of different lengths to provide for different
spray configurations. Identical nozzle units are aligned with the
slots 195 and 201 respectively.
FIG. 18 shows two nozzle units 225 and 226 mounted in the manifold
204 and aligned with the slots 191 and 197 respectively. The inner
ends 227 and 228 respectively receive liquid from within the
manifold interior 205, and the outer ends of the nozzle units 225
and 226 have jet openings 229 and 230 for emitting streams of
liquid. Identical nozzle units are aligned with the slots 194 and
200 respectively.
FIG. 19 shows two nozzle units 231 and 232 mounted in the manifold
204 and aligned with the slots 192 and 198. The inner ends 233 and
234 respectively of the nozzle units 231 and 232 receive liquid
from the manifold interior 205, and the outer ends have jet outlets
235 and 236 for spraying the liquid. Identical nozzle units are
aligned with the slots 193 and 199 respectively.
All of the nozzle units 218, 219, 225, 226, 231 and 232 may
incorporate stream straighteners, such as the stream straightener
96 shown in FIGS. 8 and 9.
The lengths of the slots 190 through 201 and the positions of the
jet outlets 222, 223, 229, 230, 235 and 236 are such that, when the
plates 208 and 209 are in the horizontal positions illustrated in
FIG. 13, the jet outlets are positioned at the upper ends of the
slots as illustrated in FIG. 12. As the plates 208 and 209 rotate
from the horizontal positions illustrated in FIG. 13 toward the
positions illustrated in FIG. 15, they rotate the manifold 204 to
swing the nozzle units, moving the jet outlets 222, 223, 229, 230,
235 and 236 downwardly within the slots. When the plates 208 and
209 have reached the upper limit of their arc of movement,
illustrated in FIG. 15, the jet outlets 222, 223, 229, 230, 235 and
236 will have moved downwardly beyond the lower edges of the slots
190-201 and will be blocked by the cylinder 189, as illustrated in
FIG. 14 and in FIGS. 20, 21 and 22. Thus, as the nozzle assembly
185 rotates and reciprocates through the approximately 45.degree.,
the entire interior of a tank will be sprayed by liquid from the
nozzle units 218, 219, 225, 226, 231 and 232. Yet, the nozzle
assembly 185 is self closing.
FIG. 23 illustrates another form of nozzle assembly 240 which is
automatically self closing whenever a liquid is being supplied to
the pipe 57. The nozzle assembly 240 is intended to be a substitute
for each of the nozzles 88, 89, 90 and 91. Each nozzle assembly 240
comprises a cylinder 241 that would be mounted in the manifold 84
in the positions shown for the nozzle cylinders 88, 89, 90 and 91
in FIGS. 7 and 8. The cylinder 241 has a bottom wall 242 into which
a valve housing 243 is threaded. The valve housing 243 has a closed
upper end 244, a cylindrical side wall 245, and a lower end 246
having a jet opening 247 through it. There are inlet openings 248
through the cylindrical side wall 245 just above the lower end 242
of the cylinder 241.
A valve member 249 is mounted within the valve housing 243 and
extends below a piston 250. The piston is above the liquid inlet
openings 248 and is biased downwardly by a compression spring 251.
An O-ring seal 252 is mounted in the side of the piston 250. If
desired, an unstressed coil spring 254 may be mounted in the space
between the valve member 249 and the cylindrical side wall 245 of
the valve housing 243, to impart a helical flow path to the
liquid.
The lower end 255 of the valve member 249 tapers to a needle 256
that projects through the jet outlet 247 when the valve member is
closed. The valve member will always be closed when no liquid is
being supplied, and, therefore, the valve assembly 240 will remain
closed. When liquid is supplied through the pipe 57 and the pipe 46
to the manifold 84, the liquid flows through the cylinder 241 of
each valve assembly 240 and thence through the openings 248. The
pressure of the liquid bears against the lower side of the piston
250 to move the piston upwardly against the force of the
compression spring 251. The force of the compression spring 251 is
light enough to yield to the aforesaid water pressure. When the
piston 250 rises, the needle 256 withdraws from the jet openings
247, and the liquid entering the openings 248 flows on to be
sprayed through to the jet opening 247. As soon as the liquid
supply is stopped, the spring 251 automatically closes the nozzle
assembly 240.
* * * * *