Note: Descriptions are shown in the official language in which they were submitted.
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SEL F-EVACUATING VACUUM CLEANER
Field of the Invention
The present invention relates to vacuum cleaners, and more
particularly to wet/dry vacuum cleaners where liquid material in the tank of
the vacuum cleaner is pumped out to waste.
background Art
Tank-type vacuum cleaners are capable of receiving dry materials
such as debris or dirt and may also be used for suctioning liquids. When the
tank is full, an upper vacuum assembly (which often includes a motor and an
air impeller) is removed and the contents are dumped out. If the vacuum
cleaner is used on liquid material, the tank, when at or near capacity, may
be very heavy so that lifting the tank, to pour the contents into a sink or
the
like, is difficult. Even tilting the tank to pour the contents into a floor
drain
may be unwieldy when the liquid level in the tank is high.
One solution to the difficulties encountered in emptying liquid from
vacuum tanks has been to provide an outlet at the bottom of the tank. Such
a solution is satisfactory when the contents of the tank are emptied into a
floor drain; however, if no floor or other low-placed drain is available the
tank must be lifted to a sink or similar disposal site. In such cases the
outlet
at the bottom of the tank is of little value.
A second solution to emptying a vacuum tank of liquid is to provide
. a pump, usually with a motor located outside of or in the bottom of the
tank.
The pump removes liquid through a lower portion of the tank and expels it
through a hose to waste. While such pumps are generally effective, they
may be very costly. The pump requires not only a pump impeller and hoses
but also its own electric motor, power cords, and switches. The expense of
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such items may be significant in the context of the overall cost
of a vacuum cleaner, particularly those designed for residential
use. Such pumps may also reduce the effective capacity of the
vacuum tank or interfere with operation when the vacuum cleaner
is used on dry materials. In addition, it may also be necessary
to provide costly or complicated structures to prime the pump,
if it is not located in the bottom of the tank.
It may also be desirable to filter debris out of the
liquid entering the tank in order to minimize interference with
the pump impeller. Vacuum cleaners often have filter bags for
capturing debris which sit inside the tank. However, such bags
are generally made of a paper-type material and, therefore, are
unsuitable for wet pick-up.
Summary of the Invention
In accordance with one aspect, the present invention
provides a vacuum cleaner comprising: a tank defining a chamber
and having an intake for receiving liquid material; an air
impeller in air flow communication with the chamber; a pump
having an inlet in fluid communication with the chamber, the
pump further comprising an interior pump chamber having a first
opening connected to the pump inlet and a second opening in air
flow communication with the chamber; a priming apparatus
disposed in the chamber and in fluid communication with the
pump inlet; and means for selectively establishing a pressure
differential across liquid in the priming apparatus to thereby
prime the pump.
The vacuum cleaner may have a pump outlet tube
connected to the pump. A pump inlet tube may also be connected
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to the pump and connected to a hollow body at the bottom of the
'tank. A valve on the pump outlet tube has an outlet for
expelling liquid pumped by the pump, and a conduit may extend
from the pump outlet tube to the hollow body. Opening the valve
allows atmospheric pressure to pass into the outlet tube and
conduit to force water in the hollow body into the inlet tube.
The valve may have an air inlet opening, and there may be a
mechanism in the valve which has a first position in which
atmospheric pressure passes through the air inlet opening. The
mechanism may have a second position in which the air inlet
opening is closed and the outlet from the valve is closed. The
mechanism may have a third position in which the air inlet
opening is closed and the outlet from the valve is open. The
hollow body may have an opening through which fluid in the tank
enters the hollow body, and a valve in the hollow body closes
the opening.
In accordance with another aspect of the present
invention, a vacuum cleaner comprises a tank having an inlet for
receiving liquid material; an air impeller in air flow
communication with the tank; a pump which draws liquid out of
the tank; a chamber in the tank for receiving liquid wherein
the chamber is in fluid communication with the pump; and a valve
selectively actuable for permitting atmospheric pressure from
outside the tank to enter the chamber to create a pressure
differential across liquid in the chamber, thereby to prime the
PAP .
The vacuum cleaner may have an inlet tube connecting
the chamber to the pump and a conduit connecting the chamber
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with the valve. The chamber may be enclosed by a hollow body,
the hollow body may have an opening through which liquid enters
the chamber, and the opening may be closed to prevent liquid
from escaping through the opening.
Other features and advantages are inherent in the
vacuum cleaner claimed and disclosed or will become apparent
to those skilled in the art from the following detailed
description in conjunction with the accompanying drawings.
Brief Description of the Drawings
FIG. 1 is a side elevational view of a vacuum cleaner
of the present invention;
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FIG. 2 is a top plan view of a vacuum cleaner of the present
invention;
FIG. 3 is a side elevational view, partially in section along the line 3-
-3 in FIG. 2;
FIG. 4 is a perspective view of an air impeller of the present
invention;
FIG. 5 is a partial view, partially in section, showing an air impeller
assembly of the present invention;
FIG. 6 is a partial side view, partially in section and partially in
phantom, showing a switch actuation assembly of the present invention;
FIG. 7 is an exploded perspective view of a portion of the switch
actuation assembly;
FIG. 8 is a partial front view, partially broken away and partially in
phantom, of the switch actuation assembly;
FIG. 9A is a partial top plan view, partially in phantom, of the
switch actuation assembly;
FIG. 9B is a partial top plan view, in section and partially in
phantom, of the switch actuation assembly;
FIG. 10 is a partial view, partially in section, showing a first half of
an outlet section of the present invention;
FIG. 11 is a bottom view, partially broken away and partially in
phantom of a ball valve in the position of Fig. 10;
FIG. 12A is a partially broken away top view of the ball valve of
FIG. 3 with the ball valve in the closed position;
FIG. 12B is a top view similar to that of FIG. 12A with the ball
valve in the partially open position;
FIG. 12C is a top view similar to Figs. 12A and B showing the ball
valve in the open position;
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FIG. 13 is a side elevational view, in section, of a pump adapter
assembly of the present invention;
FIG. 14 is a exploded view of a pressure differential apparatus of the
pump adapter assembly of FIG. 13;
FIG. 15A is an enlarged view of the pressure differential apparatus of
FIG. 13;
FIG. 15B is a cross-section taken along the line A--A of FIG. 15A of
the pressure differential apparatus;
FIG. 15C is a sectional view similar to FIG. 15B showing the
pressure differential apparatus partially filled with liquid;
FIG. 16 is a view similar to FIG. 3 with a collection bag and the
pump adapter assembly installed and a hose attached;
FIG. 17 is a perspective view of the collection bag of the present
invention;
FIG. 18A is a perspective view of the collection bag with a closure
flap in a open position;
FIG. 18B is a front elevational view of the collection bag with the
closure flap in a closed position;
FIG. 19A is a partial front view, partially broken away and partially
in phantom, of the switch actuation assembly in an "OFF" position;
FIG. 19B is a partial side view, partially in section and partially in
phantom, of the switch actuation assembly in an "OFF" position;
FIG. 20A is a partial front view, partially broken away and partially
in phantom, showing the switch actuation assembly transitioning from the
"OFF" to the "ON" position;
FIG. 20B is a partial side view, partially in section and partially in
phantom, showing the switch actuation assembly transitioning from the
"OFF" to the "ON" position;
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FIG. 21A is a partial front view, partially broken away and partially
in phantom, of the switch actuation assembly in an "ON" position;
FIG. 21B is a partial side view, partially in section and partially in
phantom, of the switch actuation assembly in an "ON" position;
FIG. 22A is a partial front view, partially broken away and partially
in phantom, showing the switch actuation assembly transitioning from the
"ON" to the "OFF" position;
FIG. 22B is a partial side view, partially in section and partially in
phantom, showing the switch actuation assembly transitioning from the
"ON" to the "OFF" position;
FIG. 23A is a partial front view, partially broken away and partially
in phantom, of a mechanical shut-off and override assembly of the present
invention in an "ON" position;
FIG. 23B is a partial side view, partially in section and partially in
phantom, of the mechanical shut-off and override assembly in an "ON"
position;
FIG. 24A is a partial front view, partially broken away and partially
in phantom, of the mechanical shut-off and override assembly moved to the
"OFF" position due to an excessively high liquid level;
FIG. 24B is a partial side view, partially in section and partially in
phantom, of the mechanical shut-off and override assembly moved to the
"OFF" position due to an excessively high liquid level;
FIG. 25A is a partial front view, partially broken away and partially
in phantom, showing the mechanical shut-off and override assembly
bypassing the mechanical shut-off;
FIG. 25B is a partial side view, partially in section and partially in
phantom, showing the mechanical shut-off and override assembly bypassing
the mechanical shut-off; and
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FIG. 26 is a view similar to FIG. 16 showing another embodiment of
the vacuum cleaner of the present invention.
Description of the Preferred Embodiment
Referring initially to Figs. 1 and 2, a vacuum cleaner of the present
invention, indicated generally at 30, has a tank 32 and an upper vacuum
assembly, indicated generally at 34.
The tank 32 is supported by casters 36 and includes a pair of handles
38. The handles 38 may be used to assist the user in lifting and moving the
vacuum cleaner 30. The tank 32 further defines an inlet 40 and a number of
latch recesses 42. The inlet 40 may be fitted with a vacuum hose (not
depicted) for applying suction at desired locations.
The tank 32 supports the upper vacuum assembly 34. The upper
vacuum assembly 34 includes a lid 44, a motor housing 46, a cover 48, and
a handle 50. The upper vacuum assembly 34 may be of conventional
construction. Except for the pump, mechanical shut-off and override
system, and priming apparatus described below, the upper vacuum assembly
34 and its associated components may be similar to a Shop Vac Model
QL20TS vacuum cleaner as manufactured by Shop Vac Corporation of
Williamsport, Pennsylvania. The lid 44 makes up the bottom of the upper
vacuum assembly 34 and carries one or more latches 52. The motor housing
46 is connected to the top of the lid 44. The cover 48, in turn, is connected
to the top of the motor housing 46, and finally, the handle 50 sits atop the
cover 48. When a user wishes to connect the upper vacuum assembly 34 to
the tank 32, the user lifts the upper vacuum assembly 34 above the tank 32,
aligns the latches 52 with the latch recesses 42, lowers the upper vacuum
assembly 34 until the lid 44 rests on top of the tank 32, and then, fastens
the
latches 52 to the tank 32.
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The motor housing 46 defines a pair of blower air discharge slots 54.
Air drawn into the vacuum cleaner 30 by the inlet 40 is expelled through the
blower air discharge slots 54 as shown by the arrow BA in Fig. 1. Also, the
motor housing 46 has a pump outlet 56 and a three position ball valve 58
extending therefrom. The cover 48 of the upper vacuum assembly 34
provides a housing for a switch actuation assembly 60 (Fig. 3), described in
detail below, which includes a user engageable actuator 62 (Fig. 2), and
extending outward from the cover 48 is an electric cord 64. The electric
cord 64 passes through a relief 65 in the cover 48 and may be permanently
attached to the motor housing 46 or detachably connected thereto. The
motor housing 46 and the cover 48 may be formed as two separate,
detachable pieces or as one piece, integral with one another. With either
construction, the motor housing 46 and the cover 48 define an air passage 66
which allows air to enter and exit the cover 48, as shown by the arrows CA
in Fig. 1.
Referring now to Figs. 3-5, disposed in the upper vacuum assembly
34, among other things, is an air impeller assembly 68. The air impeller
assembly 68 includes a housing 70 defining an opening 72, an air impeller
74, a motor shaft 76, a shaft extension 78, a flanged washer 80, and a pair
of flat washers 82 (Fig. 5). (If desired, the vacuum cleaner 30 may
alternatively use multiple air impellers.) The air impeller 74 has an upper
plate 84 and a lower plate 86 with a series of blades 88 disposed between the
upper and lower plates 84,86 (Fig. 4). The upper plate 84 defines a first
opening 90, and the lower plate 86 defines a second opening 92 having a
diameter larger than that of the first opening 90. The motor shaft 76 is
connected to a motor 93 at one end (Fig. 3 -- depicting a lower portion of
the motor 93) and is threaded at the other end 94 (Fig. 5). The shaft
extension 78 defines a threaded receptacle 96 and also has a threaded end 98
(Fig. 3).
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The air impeller 74 is disposed within the housing 70 (Fig. 5). The
threaded end 94 of the motor shaft 76 extends through the first opening 90
of the air impeller 74. The shaft extension 78 is secured to the motor shaft
76 by the engagement of the threaded end 94 of the motor shaft 76 with the
threaded receptacle 96 of the shaft extension 78. Disposed between the
upper plate 84 and the shaft extension 78 is one of the flat washers 82. The
other flat washer 82 and the flanged washer 80 encircle the motor shaft 76
and are disposed between the upper plate 84 and a motor bearing 102 (Fig.
3). From the motor shaft 76, the shaft extension 78 extends through the
second opening 92 of the air impeller 74, out through the opening 72 of the
housing 70, and connects to a pump impeller 104 by way of the shaft
extension threaded end 98 (Fig. 3). As such, the motor 93 supports the air
impeller 74 and the pump impeller 104 and drives both via the motor shaft
76 and the shaft extension 78. Alternatively, the shaft extension 78 may be
formed integral with the motor shaft 76 so that a unitary structure drives the
air impeller 74 and the pump impeller 104. Another alternative is for the
shaft extension 78 to be offset from the motor shaft 76, and torque is then
transferred from the motor shaft 76 to the shaft extension 78 via a
transmission or a gear train.
Referring to Fig. 3, the upper vacuum assembly 34 also includes a
lid cage 106 which is integrally formed with the lid 44 and extends
downward therefrom. The air impeller assembly 68 is disposed within the
lid cage 106, and the air impeller 74 draws air through the lid cage 106.
The lid cage 106 includes several braces 108 that support a bottom plate
110, and the bottom plate 110 defines a first oblong opening 112 and a
second larger opening 114. A foam filter I 16 surrounds the circumference
of the lid cage 106, and a cloth filter 118 may be placed around the lid cage
106 during dry use of the vacuum cleaner 30 to keep dust from entering the
opening 114. Instead of using a separate foam filter 116 and cloth filter
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I 18, an alternative would be to use a unitary cartridge filter that would be
easily replaceable.
Also included within the lid cage 106 is an upper pump assembly
indicated generally at 120. A pump mount I22 attaches the upper pump
assembly 120 to the air impeller housing 70. The upper pump assembly 120
includes the pump impeller 104, an upper impeller housing 124, and a lower
impeller housing 126. The pump impeller 104 is made of nylon 6, and the
upper and lower impeller housings 124, 126 are preferably made from
acrylonitrile-butadiene styrene copolymer ("ABS"). The pump impeller 104
IO has a threaded receptacle 128 and a series of blades 130; the upper
impeller
housing 124 defines an opening 132; and the lower impeller housing 126
includes an inner annular wall 134 and an outer annular wall 136. The inner
annular wall 134 has a top portion 133 which includes an annular sidewall
135 which defines an opening 137 that allows fluid communication between
IS the pump impeller 104 and the interior of the inner annular wall 134. A
screen 139 may be disposed across the interior of the inner annular wall 134
to prevent foreign objects from passing through the opening 137 and
interfering with the pump impeller 104. The outer annular wall 136 flares
out to create a flared portion 138. The lower impeller housing 126 is
20 attached to the upper impeller housing 124, and in this embodiment, the two
are threaded together. The threaded end 98 of the shaft extension 78 extends
through the opening 132 in the upper impeller housing 124 and is in
engagement with the threaded receptacle 128 of the pump impeller 104. As
a result, the pump impeller 104 is suspended between the upper impeller
25 housing 124 and the lower impeller housing 126, allowing the pump
impeller 104 to rotate freely. The diameter of the shaft extension 78 and the
diameter of the opening 132 are sized such that an annular gap 140 having a
diametral clearance on the order of 0.030 inches is created between them.
The clearance in the gap 140 may fluctuate +/- 0.015 inches due to the
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tolerances allowed in the manufacture of the shaft extension 78 and the
opening 132. The gap 140 is intentionally unsealed so that fluid is permitted
to freely flow from inside the upper impeller housing 124 to outside the
upper impeller housing 124. With the gap 140, there is no contact between
S the shaft extension 78 and the upper impeller housing 124. The lack of
contact between the two prevents the generation of frictional heat and,
therefore, reduces the need for cooling at the gap 140. Further significance
of the gap 140 is explained in detail below. A deflector 142, formed
integrally with the pump mount I22, is used to keep any liquid which
splashes up through the gap 140 from entering the air impeller assembly 68.
The upper vacuum assembly 34 also houses a mechanical shut-off
and override assembly indicated generally at 144. The mechanical shut-off
and override assembly 144 includes the switch actuation assembly 60, a float
rod 146 and a float 148. The switch actuation assembly 60 is located in the
cover 48, and the float 148 rests on the bottom plate 110 of the lid cage 106
with the float rod 146 passing through the lid 44 and the motor housing 46,
providing a linkage between the switch actuation assembly 60 and the float
148.
Referring to Figs. 6-9B, the switch actuation assembly 60 is shown in
greater detail. It should be understood that Fig. 6 (as well as Figs. 19B-
25B) does not depict a true sectional view of the switch actuation assembly
60; rather, Fig. 6 is an illustration of the switch actuation assembly 60
composed to assist in explaining the interrelation of the switch actuation
assembly elements. The precise alignment of some of the components of the
switch actuation assembly 60 are shown in the exploded view of Fig. 7. The
switch actuation assembly 60 includes a switch mount 150 (Fig. 6), a switch
152, a toggle 154, a link 156 (Fig. 6), a spring member 158 (Fig. 6) and the
user engageable actuator 62 (Fig. 6). In the preferred embodiment, the
switch mount 150, the toggle 154, and the link 156 are preferably made
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from ABS, the user engageable actuator 62 is preferably made from nylon
6/6, and the spring member 158 is preferably made from nylon. The switch
mount 150 is made from two parts: a switch box 160 and a switch cover 162
(Fig.7). Extending inward from and integrally formed with the switch box
160 is a switch box spacer 164, a first switch support rod 166, and a toggle
spacer 168 including a toggle stop 170. Extending outward from the switch
box 160 is an axle receptacle 172 and a connection flange 174 which defines
a bolt hole 176 (Fig.6). The switch cover 162 is wedge shaped and has an
inner wall 178 and an inclined outer wall 180 (Fig. 7). Cut into the outer
wall 180 is a slot 182. The bottom of the slot 182 is defined by a connection
flange 184, which also defines a bolt hole 186. Extending inward from and
integrally formed with the switch cover inner wall 178 is a second switch
support rod 188 and a toggle axle 190 (Fig. 6). The end of the toggle axle
190 seats in the axle receptacle 172 of the switch box 160. Extending
outward from and integrally formed with the switch cover outer wall 180 is
a link fastener 192. The switch cover 162 further defines an opening 194
which communicates with the slot 182. The switch cover 162 is connected
to the switch box 160 by a pair of screws 193 to form the switch mount 150.
The switch mount 150, in turn, is secured to the motor housing 46 by a pair
of bolts 196 which extend through the connection flanges 174, 184 and into
the motor housing 46 (Fig. 3).
Referring to Fig. 8, the switch 152 is a standard electrical
microswitch and includes an axle bore 198, a support bore 200, a
momentary actuator 202, an internal spring 204, and a pair of electrical
terminals 206a, 206b. The switch 152 is of the type that the switch is
normally in the "OFF" position and is "ON" only while the momentary
actuator 202 is depressed. Once the actuator 202 is released, the internal
spring 204 pushes the actuator 202 outward and returns the switch 152 to the
normally "OFF" position. In the preferred embodiment, a Unimax Model
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#TMCJG6SP0040Y made by C&K/Unimax Inc. of Willingford,
Connecticut, is used. The switch 152 is securely seated in the switch mount
box 150, and is supported by the first and second switch support rods 166,
188, which are disposed in the support bore 200 (Fig. 6), and the toggle axle
190, which is disposed in the axle bore 198.
Referring to Figs. 7 and 8, the toggle 154 is generally U-shaped and
includes a back wall 208 which defines a rod receiving extension 210 (Fig.
8) for receiving the float rod 146 (Fig. 6), a pair of sidewalls 2I2a, 212b,
and a locking brace 214 spanning between the sidewalls 212a, 212b. Both
sidewalk 212a, 212b define an axle opening 216a, 216b, and a boss 218
extends outward from one sidewall 212a (Fig. 7). The toggle 154 is
disposed in the switch mount 150 with the pair of sidewalls 212a, 212b
disposed on opposite sides of the switch 152, the sidewall 212b spaced away
from the switch box 160 by the toggle spacer 168, and the locking brace 214
disposed beneath the switch 152 (Fig. 6). As such, the toggle axle 190
extends through the axle openings 216a, 216b, and the boss 218 extends
through the opening 194 in the switch cover 162 (Fig. 6). As seen
specifically in Fig. 8, the locking brace 214 includes a ramp portion 220 and
a locking portion 222 with the locking portion 222 intersecting the ramp
portion 220 at a critical point CP. In the preferred embodiment, the
included angle between the ramp portion 220 and the locking portion 222 is
approximately 158 degrees, although this dimension may vary from such
value, as will be apparent to one of ordinary skill in the art. The angle
between the ramp portion 220 and the locking portion 222 is such that when
the toggle 154 is fully rotated counter-clockwise, as seen in Fig. 20A, the
ramp portion 220 lies flush against the bottom surface of the switch 152.
Referring to Figs. 6-9B, the link 156 defines an elongated slot 224
and a boss slot 226, and extending outward from the link 156 is a spring
member receptacle 228... The link fastener 192 is disposed in the elongated
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slot 224, and connects the link 156 to the switch mount 150. The elongation
of the slot 224 allows the link 156 to slide up and down in relation to the
switch mount 150. Also, the boss 218 of the toggle 154 extends through the
boss slot 226 (Fig. 6).
Referring to Figs. 6, 9A, and 9B, the spring member 158 includes an
actuator stem 230, a linkage web 232, a tongue 234, an upper spring 236, a
lower spring 238, and a pair of siderails 240 (Fig. 9). The linkage web 232
connects the actuator stem 230, the tongue 234, the upper spring 236, the
lower spring 238, and the siderails 240 together. The upper spring 236 and
the lower spring 238 both curve outward from the linkage web 232 and
backward from the tongue 234 toward the end of the actuator stem 230 (Fig.
6). The upper and lower springs 236, 238 are both disposed in a slot 242
formed in the cover 48 with the actuator stem 230 extending through the slot
242. The upper spring 236 engages a top lip 244 of the slot 242 creating a
first load, while the lower spring 238 engages a bottom lip 246 of the slot
242 creating a second load. In the preferred embodiment, the first load and
the second load are equally balanced, centering the user engageable actuator
62 in the slot 242 when the user engageable actuator 62 is not engaged. On
the other end, the tongue 234 is disposed in the spring member receptacle
228 (Fig. 6). The user engageable actuator 62 includes an engageable
portion 248 coupled to a hollow stem coupler 250. The hollow stem coupler
250 extends inwardly through the cover slot 242 and is disposed around the
actuator stem 230 of the spring member 158. The engageable portion 248 of
the user engageable actuator 62 is disposed on the outside of the cover 48,
and the siderails 240 engage the inside of the cover 48 creating a snug fit
between the spring member 158 and the cover 48 (Fig. 9).
Referring again to Fig. 3, the float 148 is hollow and may be made
of any suitable material, such as copolymer polypropylene. The float 148
defines a rod receptacle 252 in which the float rod 146 sits. The float rod
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146 moves in an unrestricted, non-contained linear up-and-down path in the
preferred embodiment. However, other embodiments are envisioned in
which the float rod 146 would travel in a linear up-and-down path in a
contained channel or guidance slot.
Referring to Fig. 3, the upper vacuum assembly 34 also encloses a
first half 254 of an outlet section 256 (Fig. 16). Referring to Figs. 10 and
11, the first half 254 of the outlet section 256 includes a housing 258, the
ball valve 58, and an elbow 260. The housing 258 defines the pump outlet
56, a ball seat 262, and an elbow cavity 264. The housing 258 further
includes an inlet 266 extending downward from the housing 258 and a
threaded portion 268 disposed around the exterior of the housing 258. The
inlet 266 defines a bore 270 and a check valve seat 271. A check valve 272,
which prevents air or liquid from the elbow 260 or the pump outlet 56 from
escaping through the inlet 266, is disposed in the check valve seat 271. The
ball valve 58 includes a knob 274 having three dogs 276a-c attached to a ball
278 having a passageway 280 bored therethrough for opening and closing
the valve 58. The knob 274 is disposed outside the housing 258 while the
ball 278 is seated in the ball seat 262 of the housing 258. A pair of O-rings
282, 283 situated between the ball 278 and the housing 258 creates a seal
between the ball 278 and the housing 258. Similarly, an O-ring 285 situated
between the knob 274 and the housing 258 creates a seal between the knob
274 and the housing 258. The elbow 260 defines a passageway 284 and an
adapter receptacle 286. Extending outward from and integral with the elbow
260 are a housing closure 288, a sealing flange 290 having an O-ring 292,
and a pair of connectors 294 (Fig. 11). The elbow 260 is secured in the
elbow cavity 264 of the housing 258 with screws 295 (Fig. 11) such that the
elbow 260 abuts the O-ring 282 forming a seal with the ball 278 and putting
the passageway 284 in communication with the ball 278. Also, the O-ring
292 forms a seal between the elbow 260 and the housing 258, and the
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housing closure 288 caps off the housing 258. The first half 254 of the
outlet section 256 is secured within the motor housing 46 by screwing a pair
of screws 297 through the connectors 294 and into a pair of bosses 296 in
the motor housing 46 (Fig. 3). The housing 258 extends through an opening
298 in the motor housing 46, and the adapter receptacle 286 extends through
an opening 300 in the lid 44 (Fig. 3). A hose 302 may be connected to the
housing 258 by securing a connector 304 to the threaded portion 268 of the
housing 258 (Fig. 16). The connector 304 may be of a threaded ring type
found on the ends of garden hoses.
The dogs 276a-c of the knob 274 serve to indicate the angular
position of the passageway 280 inside the housing 258. As illustrated in
Fig. 12A, the dog 276a is aligned with the pump outlet 56, and the ball 278
prevents fluid from flowing from the elbow 260 to the pump outlet 56 or
vice versa. Fluid is prevented from flowing past the ball in this position
because the passageway 280 is perpendicular to the passageway 284, and the
ball 278 forms a seal with the housing 258.
When the dog 276b is aligned with the pump outlet 56, as illustrated
in Fig. 12B, the passageway 280 is at a 45° angle to the passageway
284,
permitting only partial fluid flow from the elbow 260 to the pump outlet 56.
Also, as seen in Fig. 10, when the ball 278 is in this position, the check
valve 272 allows air in through the inlet 266 and into the elbow 260. The
ball 278 in Fig. 10 has not been sectioned so that the path air may travel
through the inlet 266 to the elbow 260 may be seen more clearly. The
arrows in Figs. 10 and 11 each show the path air takes after entering through
the inlet 266. After entering through the inlet 266, air passes through the
check valve 272 and then proceeds around the outside of the ball 278, across
the passageway 280, and into the passageway 284. Air may pass by the ball
278 in this position because opposing end sections of the ball 278 have been
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removed in creating the passage 280. As such, in this position, the ball 278
does not create a complete seal with the housing 258.
When the dog 276c is aligned with the pump outlet 56, as illustrated
in Fig. 12C, the passageway 280 is aligned with the passageway 284,
permitting full fluid flow from the elbow 260 to the pump outlet 56.
Fig. 13 depicts a pump adapter assembly 306 which includes a pump
fitting 308, a lower inlet tube 310, a pressure differential apparatus 312, a
conduit 314, and a second half 316 of the outlet section 256. The pump
fitting 308, which is preferably made from ABS, includes an upper inlet tube
318 and an outer annular wall 320 that encircles the bottom half of the upper
inlet tube 318 and is formed integrally therewith. Both the upper inlet tube
318 and the outer annular wall 320 have an O-ring 322, 324 disposed in
respective grooves 326, 328 formed in each one's upper ends. At the end
opposite the O-ring 322, the upper inlet tube 318 inserts into the lower inlet
tube 310. Extending outward from the outer annular wall 320 is a pair of
flanges 330, 332. The upper flange 330 is oblong in shape, and the lower
flange 332 is radial with the greatest diameter of the upper flange 330 being
smaller than the diameter of the lower flange 332. The outer annular wall
320 is also attached to and in fluid communication with a pump connector
334 of the second half 316 of the outlet section 256.
As best seen in Figs. 14, 15A, 15B,~ and 15C, the pressure
differential apparatus 312 includes a hollow body 336 closed by a bottom
plate 338 to form a cavity for a ball 340. The hollow body 336 includes an
opening 342 in which the ball 340 may seat (Fig. 15C). The hollow body
336 also has upward extending fittings 344, 346 (Fig. 15A), which define
openings 348, 350 (Fig. 15A), for attaching, respectively, the lower inlet
tube 310 and the conduit 314. A top plate 352 is attached to the hollow
body 336 by screws 353. As best seen in Fig. 14, the top plate 352 has
openings 354, 356 through which the inlet tube 310 and the conduit 314
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respectively pass. The top plate 352 and the bottom plate 338 enclose a
filter 358 ensuring that any liquid passing into the hollow body 336 through
the opening 342 also passes through the filter 358.
Returning now to Fig. 13, the second half 316 of the outlet section
256 includes the pump connector 334, a flexible tube 360, and a rotatable
connector 362. The pump connector 334 attaches to the outer annular wall
320 of the pump fitting 308 at one end, as described above, and attaches to
the flexible tube 360 at the other end. The other end of the flexible tube 360
attaches to the rotatable connector 362. The pump connector 334 includes a
check valve 364 and a conduit fitting 366. The check valve 364 permits
flow from the pump fitting 308 into the pump connector 334, but the check
valve 364 does not permit flow from the pump connector 334 into the pump
fitting 308. The conduit 314, at one end, connects to the conduit fitting 366
of the pump connector 334. The conduit fitting 366 is disposed on the outlet
side of the check valve 364 so that any fluid passing down through the
flexible tube 360 can pass into the conduit 314 without being blocked by the
check valve 364. The conduit 314, at the other end, fits into the fitting 346
in the hollow body 336. In between the two conduit ends, a clamp 368
holds the conduit 314 against the lower inlet tube 310.
Referring to Fig. 26, another embodiment of the present invention is
illustrated. Elements similar to the elements identified in previous
embodiments have been given the same reference numerals. In this
embodiment, the check valve 364 has a pointed end 365 and is forced into a
seat 367 by a spring 369. The interaction of the pointed end 365 of the
check valve 364, the spring 369 and the seat 367 creates a positive seal
between the pump fitting 308 and the pump connector 334 during the
priming of a pump indicated generally at 372 whose operation is explained
in detail below. A stiffening tube 371 is disposed within the lower inlet tube
310 to help keep the pressure differential apparatus 312 fixed in place during
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operation of the vacuum cleaner 30. Also, in this embodiment, the clamp
368 which holds the conduit 314 against the lower inlet tube 310 is removed,
and instead, the conduit 314 is wrapped around the lower inlet tube 310 one
or more times to keep the conduit 314 from moving freely within the tank
32. Twisting the conduit 314 around the lower inlet tube 310 instead of
using the clamp 368 reduces the tension created between the conduit 314 and
the lower inlet tube 310 and allows the conduit 314 to shift with respect to
the lower inlet tube 310 when contracting or expanding. The filter 358 is
replaced by a screen 373 in this embodiment, which may be made from
plastic. The screen 373 is better suited for use when vacuuming large
particulate material because the screen 373 will not clog as often as the
filter
358. The screen 139 across the interior of the inner annular wall 134 is
removed in this embodiment, and the annular sidewall 135 which defines the
opening 137 is extended downward to form a restricted fluid passage 375.
The reduced diameter of the restricted fluid passage 375 helps prevent the
user from interfering with the pump impeller 104 at rest or during operation.
In this embodiment, the inlet 266 of the housing 258 no longer defines a
check valve seat 271 for the check valve 272 to be disposed within. Rather,
a retaining ring 377, a washer in this embodiment, is disposed in the inlet
266 to act as the check valve seat 271 for the check valve 272.
The vacuum cleaner 30 may be operated in two modes: dry and wet
vacuuming mode. Fig. 3 shows the vacuum cleaner 30 in dry mode
configuration. The ball valve 58 is in a closed position to maintain the
pressure differential in the tank 32, and the cloth filter 118 is in place
around
the lid cage 106 to keep dust from entering the opening 114. To convert the
vacuum cleaner 30 of any embodiment to wet mode operation, the cloth
filter 118 is removed, and the pump adapter assembly 306 is installed (Figs.
16 and 26). To install the pump adapter assembly 306 and create the pump
372, the user first inserts the pump fitting 308 through the openings 112,
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114 in the lid cage bottom plate 110 and into the lower impeller housing I26
of the upper pump assembly 120. The flared portion 138 of the upper pump
assembly 120 facilitates insertion of the pump adapter assembly 306 into the
lower impeller housing 126. During insertion, the upper inlet tube 318
slides within the inner annular wall 134 of the lower impeller housing 126,
and the O-ring 322 forms a seal with the inner annular wall 134. The screen
139 (Fig. 16) or the extended annular sidewall 135 (Fig. 26) is disposed
between the upper inlet tube 318 and the opening 137. Similarly, the outer
annular wall 320 of the pump fitting 308 slides within the outer annular wall
136 of the lower impeller housing 126, and the O-ring 324 forms a seal with
the outer annular wall 136. Lastly, the radial flange 332 seats in the opening
114.
To secure the pump adapter assembly 306 to the lid cage 106, the
user twists the pump adapter assembly 306 ninety degrees, causing the pump
fitting 308 to also turn placing the oblong flange 330 in contact with the
bottom plate 110 of the lid cage 106. To finish connecting the pump adapter
assembly 306 to the upper vacuum assembly 34, the user manipulates the
rotatable connector 362 and inserts the rotatable connector 362 into the
adapter receptacle 286. The completed pump 372 includes a priming
chamber 374 and a discharge recess 376. The priming chamber 374 is
defined by the cooperation of the upper inlet tube 318, the O-ring 322, the
inner annular wall 134, and the pump impeller 104. The discharge recess
376 is defined by the cooperation of the outer annular wall 136 of the lower
impeller housing 126, the O-ring 324, and the outer annular wall 320 of the
pump fitting 308. The dimension of each of the parts of the pump 372 will
be dependent on the desired flow rate of the pump 372. In addition, the
power of the motor 93 may also affect the size and design of many
components, including the pump impeller 104.
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If the user desires to filter large particulate material out of the
material being drawn into the vacuum cleaner 30 of any embodiment, the
user may install a mesh collection bag 370 into the tank 32 (Fig. 16). (A
mesh collection bag 370 may also be used in the embodiment depicted in
Fig. 26.) Referring to Figs. 17, 18A, and 18B, the mesh collection bag 370
includes a filter section 378, a closure flap 380, and an inlet collar 382.
The
filter section 378 includes a front portion 384 and a back portion 386. Three
edges 388a-c of the front and back portions 384, 386 are permanently
connected together. The closure flap 380 is an elongated section of the back
portion 386 of the filter section 378 and is disposed opposite a fourth edge
389 of the front portion 384 to form an opening 391. The dimensions of the
apertures in the mesh of the filter section 378 are preferably approximately
0.5 mm by 1 mm. The filter section 378 is made from nylon or other
material which is strong and not water soluble. The filter section 378 is
generally rectangular in shape and is sized so that the bottom of the filter
section 378 just touches the bottom of the tank 32 when installed (Fig. 16).
The inlet collar 382 includes a first and second portion 393a, 393b (Figs.
18A and 18B). The first portion 393a of the inlet collar 382 is a rigid
reinforcement piece, which may be made of a hard plastic material, which
defines an opening 397 and is centered on an outer surface 395 of the
closure flap 380 (Fig. 18B). The second portion 393b of the inlet collar 382
is attached to the top center of the front portion 3.84 of the filter section
378
and defines an opening 399 (Fig. 18A). The second portion 393b of the
inlet collar 382 has a gummy flexible sleeve 392, which may be made of a
rubber material, and a rigid reinforcement portion 394, which may also be
made of a hard plastic material, with the sleeve 392 being sandwiched
between the reinforcement portion 394 and the front portion 384 of the filter
section 378. To install the mesh collection bag 370, the user first folds the
closure flap 380 over the opening 391 and the fourth edge 389 of the front
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portion 384. The user then places the mesh collection bag 370 into the tank
32 and spreads the mesh collection bag 370 around the inner circumference
of the tank 32 (Fig. 16). The user then aligns the openings 397, 399 of the
inlet collar 382 with the inlet 40 of the tank 32 and slides the inlet collar
382
S over the inlet 40. The flexible sleeve 392 will stretch outward as the inlet
collar 382 is pushed onto the inlet 40. Once the inlet collar 382 is in place,
the sleeve 392 has a diameter small enough and is made from a material
gummy enough to securely grip the inlet 40. Finally, to complete
preparation of the vacuum cleaner 30 for wet mode operation, the user
inserts the combined upper vacuum assembly 34/pump adapter assembly 306
into the tank 32 and then secures the lid 44 to the tank 32 with the latches
52
as described above (Fig. 16).
To operate the vacuum cleaner 30 in wet mode operation (operation
of the switch actuation assembly 60 is the same for dry mode operation), the
user first turns the motor 93 "ON" by turning the switch 152 "ON". The
switch actuation assembly 60 is initially in the "OFF" position as illustrated
in Figs. 19A and 19B. In the "OFF" position, the locking brace 214 of the
toggle 154 is not engaging the momentary actuator 202 and the user
engageable actuator 62 is centered in the slot 242 by the equally balanced
upper and lower springs 236, 238. As illustrated in Figs. 20A and 20B, to
turn the motor 93 "ON", the user presses upward on the engageable portion
248 of the user engageable actuator 62. The upward force is transmitted to
the spring member 158 and to the link 156. The upward force on the spring
member 158 presses the upper spring 236 against the top lip 244 of the slot
242, creating a load. The upward force on the link 156 moves the boss slot
226 upward. As the boss slot 226 moves upward, the boss slot 226 engages
the boss 218 of the toggle 154. Continued upward movement of the boss
slot 226 moves the boss 218 upward and causes the toggle 154 to rotate
counter-clockwise (as seen in Figs. 20A and B) around the toggle axle 190
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(Fig. 6). The top of the opening 194 in the switch cover 162 keeps the user
from pulling the boss 218 too far upward and prevents possible damage to
the switch 152 by keeping the toggle 154 from pressing too far upward on
the switch 152. The counter-clockwise rotation of the toggle 154 moves the
ramp portion 220 into engagement with the momentary actuator 202,
pressing the momentary actuator 202 into the switch 152. Continued
counter-clockwise rotation of the toggle 154 slides the ramp portion 220
laterally along the momentary actuator 202. Eventually, the momentary
actuator 202 passes the critical point CP and comes in contact with the
locking portion 222 of the locking brace 214. At this point, the momentary
actuator 202 is no longer resisting the counter-clockwise rotation of the
toggle 154; rather, the momentary actuator 202 is now locking the toggle
154 against the switch 152 by pushing downward on the locking brace 214,
causing the momentary actuator 202 to remain depressed (Figs. 20A and
20B). The depressed momentary actuator 202 turns the switch 152 "ON",
which in turn supplies power to the motor 93. Once the user releases the
user engageable actuator 62, the load created on the upper spring 236 is
released, and the spring member 158 re-centers the user engageable actuator
62 in the slot 242 (Figs. 21A and 21B).
The energized motor 93 simultaneously turns the air impeller 74 and
the pump impeller 104 via the motor shaft 76/shaft extension 78 combination
(Figs. 16 and 26). The rotating air impeller 74 reduces the pressure in the
tank 32, creating a vacuum. The vacuum draws air, liquid and/or other
material into the tank 32 through the inlet 40. As material is sucked into the
tank 32 through the inlet 40, the mesh collection bag 370 filters out any
exceptionally large particulate material to reduce the possibility of clogging
the pump 372. Even if the pump 372 is not used, the mesh collection bag
370 can be used to easily filter large particulate material out from the
liquid
in the tank 32 so that when the tank 32 is poured or emptied into a drain the
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large particulate material will not clog the drain. The air that is drawn into
the tank 32 passes through the foam filter 116, through the lid cage 106, into
the motor housing 46, and finally is expelled out of the discharge slots 54
(Fig. 1).
The pump 372 is a self-priming pump under most conditions.
Referring to Figs. 15C and i6, when the ball 340 seats in the opening 342 a
high-pressure system is created in the passageway 284, the flexible tube 360,
and the conduit 314 by air under atmospheric pressure being trapped
between the closed ball valve 58 (Fig. 12A) and the liquid collecting in the
hollow body 336 of the pressure differential apparatus 312. Meanwhile, a
low pressure system is created in the inlet tubes 310, 318 since the gap 140
in the upper impeller housing 124 places the inlet tubes 310, 318 in
communication with the low-pressure area created by the air impeller 74.
The low-pressure air trapped in the inlet tubes 310, 318 does not create
enough head to pull the liquid collected in the hollow body 336 up through
the inlet tubes 310, 318 to prime the pump 372. The check valve 364 acts to
keep the low-pressure system created in the inlet tubes 310, 318 separate
from the high-pressure system created in the passageway 284, the tube 360,
and the conduit 314. The high-pressure system and the low-pressure system
act together to create a pressure differential across the liquid in the hollow
body 336 by the high-pressure (essentially atmospheric) air pushing the
liquid in the hollow body 336 up through the inlet tubes 310, 318 and into
the priming chamber 374, displacing the low-pressure air and priming the
pump 372.
The primed pump 372 will then pump the collected liquid out of the
tank 32. The liquid collected in the tank 32 will flow from the tank 32
through the filter 358 (Fig. 16) or screen 373 (Fig. 26) into the hollow body
336, up the inlet tubes 310, 318 (and through the stiffening tube 371 if one
is in place), into the priming chamber 374 and up to the pump impeller 104.
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Some of this liquid will splash through the gap 140, but the majority of this
liquid will flow downward into the discharge recess 376, past the check
valve 364, and into the outlet section 256. The O-ring 324 will prevent any
liquid from leaking between the interface of the outer annular wall 320 of
the pump fitting 308 and the outer annular wall 136 of the lower impeller
housing 126. Once in the outlet section 256, the liquid will flow through the
pump connector 334, the tube 360, the rotatable connector 362, the
passageway 284, the passageway 280, and out the pump outlet 56 through
the hose 302, if connected, to a drainage source (not depicted). Once
primed, the user can turn the knob 274 so that the dog 276c is aligned with
the pump outlet 56, thus putting the passageway 280 in alignment with the
passageway 284 to permit the liquid to discharge at a maximum flow rate
(Fig. 12C). This self priming action of the present invention is a unique
aspect of this design.
If conditions are such that the pump 372 will not self prime, the user
may enable the priming system by rotating the knob 274 to its 45°
position
so that dog 276b aligns with the pump outlet 56 (Fig. 12B). The relatively
high-pressure outside air, at atmospheric pressure, will enter the inlet 266
(Figs. 10 and 11) and fill the passageway 284, the flexible tube 360, and the
conduit 314, creating a high-pressure system like the one described above.
This high-pressure system will create a pressure differential across the
liquid
in the hollow body 336 and prime the pump 372 in the same manner as
described above.
Another unique design feature of the present invention is that the
pump 372, once primed, is not likely to lose its prime due to deterioration of
the O-ring 322. When the pump 372 is pumping liquid out, the O-ring 322,
which forms a seal between the upper inlet tube 318 and the inner annular
wall 134 of the lower impeller housing 126, is surrounded by liquid on both
sides because both the priming chamber 374 and the discharge recess 376 are
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filled with liquid. As such, even if the O-ring 322 begins to deteriorate, air
will not be able to enter the priming chamber 374 and cause the pump 372 to
lose its prime. The pump 372 will, however, operate less efficiently in this
situation.
Referring to Figs. 16 and 23-26, if, while vacuuming, the level of
the liquid in the tank 32 gets too high, the mechanical shut-off and override
assembly 144 will automatically shut-off the motor 93. When the liquid in
the tank 32 gets to the level of the float 148, the liquid pushes the float
148
upward. Simultaneously, the float 148 pushes the float rod 146 upward in
the rod receiving extension 210 of the toggle i54. Eventually, the rising
liquid reaches a level high enough to create an upward force so that the float
rod 146 pushes the toggle 154 clockwise, disengaging the toggle 154 from
the switch 152. Once the toggle 154 is disengaged from the switch 152, the
momentary actuator 202, due to the force of the internal spring 204, springs
outward turning the switch 152 "OFF" (Figs. 24A and 24B) which stops the
motor 93 and, consequently, stops the air impeller 74 and the pump impeller
104 from rotating. The float 148 should be placed at a height low enough so
that the motor 93 is turned "OFF" before the level of liquid is high enough
to begin entering the air impeller 74. Once the motor 93 has been turned
"OFF", the user has two options: the user may either remove the upper
vacuum assembly 34 and manually empty the tank 32 or the user may bypass
the float shut-off by mechanically overriding the float shut-off.
To manually empty the tank 32, the user unfastens the latches 52 and
lifts off the upper vacuum assembly 34. While lifting the upper vacuum
assembly 34, the motor 93 will not inadvertently turn "ON" . The present
invention has a number of design features incorporated within it to keep the
toggle 154 from re-engaging the momentary actuator 202, which would
cause the motor 93 to turn "ON", while the upper vacuum assembly 34 is
being lifted from the tank 32. First, the toggle 154 is intentionally not
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connected to the float rod 146. If the toggle 154 was formed integral with
the float rod 146, the float rod 146 would cause the toggle 154 to rotate
counter-clockwise while the upper vacuum assembly 34 was being lifted and
would possibly re-engage the momentary actuator 202. Second, the outward
force of the internal spring 204 of the switch 152 is enough to keep the
toggle from inadvertently depressing the momentary actuator 202 while the
upper vacuum assembly 34 is being lifted. Once the upper vacuum assembly
34 is removed, the user lifts the tank 32, removes the mesh collection bag
370, and dumps the contents of the tank 32 into a drainage source.
Instead of dumping the contents of the tank 32, the user may
mechanically bypass the float shut-off, by pushing upward on the user
engageable actuator 62 (Figs. 25A and 25B). As discussed above, the
upward movement of the user engageable actuator 62 moves the boss 218
upward which causes the toggle 154 to rotate counter-clockwise The toggle
154 rotates into contact with and depresses the momentary actuator 202
again. Once the momentary actuator 202 is depressed, the motor 93 turns
back "ON", and the user can continue pumping liquid out of the tank 32.
However, in this situation, the user must hold the user engageable actuator
62 upward until a sufficient amount of liquid has been pumped out of the
tank 32 so that the liquid level is below the motor shut-off level; otherwise,
the liquid will continue to push the float 148 upward which will push the
toggle 154 clockwise again, turning the motor 93 "OFF". Once the user has
pumped out enough liquid to put the liquid level in the tank 32 below the
motor shut-off level, the motor 93 will stay "ON" when the user releases the
user engageable actuator 62, and the user may resume normal operation of
the vacuum cleaner 30.
When the user is finished either vacuuming or pumping with the
vacuum cleaner 30, the user turns the vacuum cleaner 30 "OFF" by pushing
downward on the user engageable actuator 62 (Figs. 22A and 22B). The
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downward force is transmitted to the spring member 158 and to the link 156.
The downward force on the spring member 158 presses the lower spring 238
against the bottom lip 246 of the slot 242, creating a load. The downward
force on the link 156 moves the boss slot 226 downward. As the boss slot
226 moves downward, the boss slot 226 engages the boss 218 of the toggle
154. Continued downward movement of the boss slot 226 moves the boss
218 downward and causes the toggle 154 to rotate clockwise around the
toggle axle 190 (Fig. 6). The bottom of the opening 194 in the switch cover
162 and the toggle stop 170 keep the toggle 154 from traveling too far
backward. The clockwise rotation of the toggle 154 disengages the locking
brace 214 from the momentary actuator 202. As such, the internal spring
204 of the switch 152 pushes the momentary actuator 202 outward and turns
the switch 152 "OFF" , which in turn shuts off the motor 93. Once the user
releases the user engageable actuator 62, the load created on the lower spring
238 is released, and the spring member 158 re-centers the user engageable
actuator 62 in the slot 242 (Figs. 19A and 19B).
The vacuum cleaner of the present invention has significant
advantages over prior vacuum cleaners. By providing a pump to remove
liquid from the tank, liquid can be emptied easily into drains at a variety of
heights. Driving the pump impeller off of the same motor which drives the
air impeller significantly reduces the cost of the vacuum cleaner over designs
which require a separate motor for the pump. By locating the pump in the
tank directly below the air impeller, the pump impeller can be simply and
efficiently driven off a single axle connected to the air impeller.
Removability of the pump adapter assembly provides significant efficiency
when the vacuum cleaner is used on dry material.
The mechanical shut-off and override assembly of the present
invention also provides significant advantages. The mechanical shut-off and
override assembly automatically shuts off the motor when the liquid level in
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the vacuum cleaner tank gets too high. This assembly then allows the user
to bypass the vacuum cleaner mechanical shut-off and continue to pump
liquid out of the tank without requiring the user to lift or tilt the tank to
empty it. Also, the priming assembly of the present invention provides a
simple, easy to use, and cost effective priming system.
The foregoing detailed description has been given for clearness of
understanding only, and no unnecessary limitations should be understood
therefrom, as modifications would be obvious to those skilled in the art.
