Information
-
Patent Grant
-
6685778
-
Patent Number
6,685,778
-
Date Filed
Thursday, October 25, 200123 years ago
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Date Issued
Tuesday, February 3, 200420 years ago
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Inventors
-
Original Assignees
-
Examiners
Agents
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CPC
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US Classifications
Field of Search
US
- 118 684
- 118 207
- 118 244
- 118 262
- 118 264
- 015 503
- 015 4
- 015 98
- 015 320
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International Classifications
-
Abstract
A lane maintenance machine having wicks that absorb dressing from a reservoir and transfer it to the applicator of the machine has a gravity-fed dressing supply system that maintains the dressing at a substantially constant level within the wick reservoir. A small pilot chamber upstream from the reservoir and in open communication therewith at the same elevation as the reservoir has its fluid level directly controlled by a float sensor to in turn indirectly control the level within the wick reservoir. The float sensor within the pilot chamber provides a signal to a controller when the level within the pilot chamber drops below a predetermined point so that a control valve between the pilot chamber and the main supply tank opens to allow a makeup volume of dressing to flow by gravity from the main tank into the pilot chamber. Vent conduits associated with the main tank and the pilot chamber also serve as a means for accepting dressing that drains from the reservoir when the machine is upended into a transport position, thus preventing spillage of dressing through the open top of the wick reservoir.
Description
TECHNICAL FIELD
The present invention relates to the field of maintenance machines that apply oil or other dressing to the surface of bowling lanes and, more particularly, to improvements in the manner in which the dressing is supplied to applicator wicks used in such machines.
BACKGROUND
It is known in the prior art that wick-type lane maintenance machines, wherein wicks are used to absorb lane oil from a reservoir and apply it to a transfer roller or other applicator, perform best when the oil within the reservoir is maintained at a substantially constant, predetermined level. If the oil level is allowed to decrease significantly, the rate of oil transferred by the wick will drop, which makes it difficult to apply an identical oil pattern to all lanes of a bowling establishment. In prior U.S. Pat. No. 5,650,012 assigned to the assignee of the present invention, the oil level within the wick reservoir is maintained substantially constant by continuously pumping oil from a supply tank into the wick reservoir and having it overflow and return back to the supply tank. Thus, the oil level is maintained at the level of the overflow outlet.
In one alternative embodiment disclosed in the '012 patent, the oil from the pump flows first into a small chamber immediately upstream from the wick reservoir that is in constant communication with the wick reservoir. The overflow outlet remains located in the wick reservoir and overflowing oil is returned back to the main supply tank.
SUMMARY OF THE INVENTION
In accordance with the present invention a lane maintenance machine that uses absorbant wicks as part of the dressing application system of the machine automatically maintains dressing at a substantially constant level in the wick reservoir without the use of a pump or overflow system as found in the prior art. The present invention relies solely upon gravity to feed makeup dressing to the wick reservoir if and when such dressing is necessary to maintain the predetermined, optimum level of dressing in the reservoir. A float switch functions to determine whether the level is below the set point and, if so, it signals a controller or otherwise causes a control valve to open a supply conduit from an elevated main tank so that makeup dressing can flow by gravity into the reservoir. In a preferred embodiment of the invention, a relatively small pilot chamber upstream from the wick reservoir but in open communication therewith is placed at such a height that the fluid level in the pilot chamber and the wick reservoir are always the same. Thus, the level of fluid in the wick reservoir can be indirectly controlled by controlling the fluid level in the pilot chamber. To this end, the float sensor is located within the pilot chamber, rather than in the wick reservoir. Constant opening and closing of the float switch as it seeks to maintain a constant fluid level is prevented by having a relatively long stretch of supply conduit between the control valve and the pilot chamber so that, even after the float switch has been deactuated by the fluid level returning to its set point, the volume of fluid in the supply conduit downstream from the pilot valve overfills the control chamber to a certain extent above the set point.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1
is a fragmentary vertical cross sectional view through a lane machine incorporating one preferred embodiment;
FIG. 2
is a fragmentary top plan view thereof with one of the wick assemblies removed to reveal details of construction of the dressing supply system in accordance with the present invention;
FIG. 3
is a fragmentary vertical cross sectional view through the machine taken generally along line
3
—
3
of
FIG. 1
;
FIG. 4
is a fragmentary isometric view of the wick reservoir and dressing supply system in accordance with the present invention; and
FIG. 5
is an isometric view of the wick reservoir and associated wicks and solenoid actuators of the machine.
DETAILED DESCRIPTION
The present invention is susceptible of embodiment in many different forms. While the drawings illustrate and the specification describes certain preferred embodiments of the invention, it is to be understood that such disclosure is by way of example only. There is no intent to limit the principles of the present invention to the particular disclosed embodiments.
The lane machine
10
shown throughout the figures may, for example take the form of that illustrated in U.S. Pat. No. 5,650,012. Accordingly, the '012 patent is incorporated herein by reference for a disclosure of those aspects of machine
10
not specifically set forth in the description and drawings of the present specification. In view of the foregoing incorporation by reference, and in view further of the level of ordinary skill in the art and state of the prior art in general, many of the components of machine
10
are only schematically illustrated and will only be briefly discussed herein.
Lane oil or other dressing is applied to the lane by a brush-type applicator roll
12
that spans the lane and makes contacting engagement therewith as the machine moves from right to left viewing FIG.
1
. Applicator roll
12
receives its oil from a transfer roll
14
that is at least coextensive in length with applicator
12
and extends parallel thereto. Transfer roll
14
in turn receives its oil from a bank of absorbent wicks
16
, each of which can be flexed into and out of contacting engagement with transfer roll
14
by its own solenoid actuator
18
, cable
20
and return spring
22
. Wicks
16
are received within a generally transversely U-shaped, open top reservoir
24
, the depth of reservoir
24
being such that a lower portion of each wick is housed within reservoir
24
while an upper portion projects upwardly out of and beyond reservoir
24
for contacting engagement with transfer roll
14
, unless that particular wick
16
has been pulled out of such contact by its solenoid
18
. Reservoir
24
contains oil that is absorbed by wicks
16
and which migrates to the upper portion thereof by capillary action.
Wick reservoir
24
has a back wall
26
to which is integrally secured a relatively small, rectangular pilot chamber
28
. The bottom of pilot chamber
28
is located at substantially the same level as the bottom of the rear wall
26
, while the top of pilot chamber
28
is located at substantially the same level as the upper edge of the front wall
30
of reservoir
24
. A horizontal slot
32
in back wall
26
adjacent its lower extremity communicates the interior of pilot chamber
28
with the interior of reservoir
24
. Pilot chamber
28
passes through an upright structural bulkhead
34
within machine
10
, while opposite ends of reservoir
24
are fixedly secured to bulkhead
34
by generally L-shaped angle brackets
36
(only one being shown; see FIGS.
4
and
5
).
Pilot chamber
28
serves as an indirect means of maintaining a substantially constant level of oil within reservoir
24
. To this end, pilot chamber
28
contains a liquid level sensor
38
in the nature of a float switch that signals a controller (not shown) or completes a control circuit for actuating a control valve
40
to open and close a supply conduit
42
leading downhill from valve
40
to pilot chamber
28
. Because pilot chamber
28
is located below control valve
40
, oil allowed to enter conduit
42
at its upper end by control valve
40
flows by gravity into the pilot chamber
28
via an inlet
44
within the top wall of chamber
28
. In one preferred embodiment, sensor
38
comprises a magnetic float switch available from Madison Company as part number M8700, while control valve
40
comprises an electrically actuated shut-off valve available from Snap Tite Valves, part number 2823B-2NT-VCF.
Control valve
40
is connected via another supply conduit
46
to the bottom region of a main supply tank
48
, the tank
48
being located at a higher elevation than control valve
40
so that oil flows by gravity from tank
48
to control valve
40
via the downwardly inclined supply conduit
46
. A removable cap
50
on tank
48
permits periodic refilling of tank
48
.
The dressing supply system thus far described is provided with a number of vent lines that not only serve to vent tank
48
and control chamber
28
to the atmosphere, but also serve as temporary storage space for dressing that drains from reservoir
24
when machine
10
is upended 90° and placed in a transport position wherein ground wheels
52
(
FIGS. 1 and 2
) support the machine for easy rolling thereof to and from the operating site. In this regard, a generally T-shaped fitting
54
rises from the top wall of chamber
28
in open communication with the interior thereof and is joined with a vent conduit
56
that passes through bulkhead
34
and runs up hill from fitting
54
to a point generally adjacent the proximal end of transfer roll
14
. Another vent conduit
58
leads from the top wall of tank
48
down to fitting
54
to establish open communication between the upper region of tank
48
and vent conduit
56
. A third vent conduit
60
leads from the top wall tank
48
directly to the vent conduit
56
generally adjacent the outboard end of conduit
56
. Vent conduit
60
connects to tank
48
at a location spaced laterally from the connection of vent conduit
58
to tank
48
.
Operation
In use, machine
10
is positioned as illustrated in
FIG. 1
with the applicator roll
12
contacting the lane surface. As machine
10
advances along the lane, the rotating applicator roll
12
applies lane dressing thereto in a predetermined pattern determined by a controller of the machine which causes different ones of the wicks
16
, or all of them, to be flexed into and out of contacting engagement with transfer roll
14
at certain locations along the lane. Oil contained within pilot chamber
28
flows freely to wick reservoir
24
via open slot
32
, and the level of oil within reservoir
24
matches that within pilot chamber
28
due to hydraulic pressure.
If the level within pilot control chamber
28
drops below the desired point, that condition is sensed by float switch
38
which in turn signals the controller to open control valve
40
. When control valve
40
opens, oil from tank
48
and supply conduit
46
flows by gravity through valve
40
and supply conduit
42
into chamber
28
to replenish the supply. When float switch
38
is then closed by the rising oil level within chamber
28
, a signal is received by the controller which in turn re-closes control valve
40
. This shuts off supply conduit
46
so that no additional fluid can reach supply conduit
42
; however, there is a significant residual amount left in supply conduit
42
when valve
40
is re-closed, and that amount continues to gravitate into chamber
28
until supply conduit
42
is completely emptied. Thus, to a certain extent, control chamber
28
is somewhat overfilled during each refill cycle, although the relatively small volume of chamber
28
compared to the much larger volume of reservoir
24
causes such overfilling to have very little effect on the level of oil within reservoir
24
. Consequently, using the benefits of gravity flow, the level of oil within reservoir
24
can be maintained at substantially the same level throughout the life of the supply of oil within main tank
48
.
It will be noted that as the supply of oil drops within main tank
48
, the void left by the departing dressing is immediately filled by ambient air at atmospheric pressure via the vent conduits
56
,
58
and
60
. Moreover, it will be noted that when machine
10
is upended into its transport position wherein wheels
52
are engaging the ground, oil drains from reservoir
24
into chamber
28
via open slot
32
. To the extent chamber
28
is unable to handle the volume of oil coming from reservoir
24
, such additional volume flows into one or more of the vent conduits
56
,
58
and
60
via the fitting
54
. A certain amount can also be accepted by the supply conduit
42
via inlet
44
.
Float switch
38
can also serve as a means of alerting the operator to a low oil condition or that a problem exists with the oil flow, such as an obstruction in the supply line. Typically, during normal operations, switch
38
closes for only short intervals of time, e.g. less than thirty seconds each. Thus, if switch
38
remains closed for more than thirty seconds, for example, it is probably attempting to supply more oil to pilot chamber
28
than is available, for one reason or another. Such prolonged closure of switch
38
can be recognized by the controller (not shown) of the machine, which in turn causes an appropriate error message to appear on a display (not shown) of the machine that alerts the operator to take appropriate steps to rectify the problem.
Although preferred forms of the invention have been described above, it is to be recognized that such disclosure is by way of illustration only, and should not be utilized in a limiting sense in interpreting the scope of the present invention. Obvious modifications to the exemplary embodiments, as hereinabove set forth, could be readily made by those skilled in the art without departing from the spirit of the present invention.
The inventor(s) hereby state(s) his/their intent to rely on the Doctrine of Equivalents to determine and assess the reasonably fair scope of his/their invention as pertains to any apparatus not materially departing from but outside the literal scope of the invention as set out in the following claims.
Claims
- 1. In a bowling lane maintenance machine having a lane dressing application system, the improvement comprising:a roller; a dressing reservoir adjacent said roller; a wick received within said reservoir and having a portion that projects upwardly out of the reservoir for use in transferring dressing to said roller by contacting engagement therewith; a dressing supply tank coupled with the reservoir in a manner to provide dressing to the reservoir by gravity flow; a control valve operable when open to permit dressing flow from the tank to the reservoir by gravity and when closed to preclude such flow; and a dressing level sensor operably coupled with said valve for opening and closing the valve in a manner to maintain the level of dressing within the reservoir substantially constant.
- 2. In a bowling lane maintenance machine as claimed in claim 1,further including a pilot chamber upstream from the reservoir and downstream from the supply tank, said pilot chamber being in open flow communication with the reservoir and being located at such a height that dressing in the pilot chamber and the reservoir are maintained at substantially the same level, said sensor being located within said pilot chamber and being responsive to changes in the level of dressing within said pilot chamber.
- 3. In a bowling lane maintenance machine as claimed in claim 2,said pilot chamber being substantially shorter than said reservoir in a direction transverse to the path of travel of the machine.
- 4. In a bowling lane maintenance machine as claimed in claim 2,said sensor comprising a float switch.
- 5. In a bowling lane maintenance machine as claimed in claim 2,further including a dressing supply conduit extending between the control valve and the pilot chamber, said supply conduit being disposed to receive dressing that drains from the pilot chamber when the machine is upended for transport.
- 6. In a bowling lane maintenance machine as claimed in claim 5,further including vent conduits communicating the supply tank and the pilot chamber with atmosphere, said vent conduits being disposed to receive and collect dressing that drains from the pilot chamber when the machine is upended for transport.
- 7. In a bowling lane maintenance machine as claimed in claim 1,said sensor comprising a float switch.
US Referenced Citations (3)
Number |
Name |
Date |
Kind |
5650012 |
Davis |
Jul 1997 |
A |
5679162 |
Caffrey et al. |
Oct 1997 |
A |
5729855 |
Davis |
Mar 1998 |
A |