Abstract:
A lane maintenance machine has a cleaning system that includes at least one cleaning liquid dispensing head which reciprocates back and forth transversely of the lane as the machine travels along the length of the lane. In a preferred embodiment the dispensing head emits successive squirts of liquid from a positive displacement pump, such as a peristaltic pump. The positive displacement pump provides accurate, precise metering of the cleaning liquid and affords board-by-board control of the dispensing action. A wiping assembly immediately behind the cleaning liquid dispensing head provides a web of cloth-like material looped under a compressible backup roller to wipe the applied liquid into a thin film and to pick up a measure of the liquid along with oil and dirt. A vacuum squeegee pickup head trailing the wiping assembly lifts the remaining film of cleaning liquid completely off the lane surface, whereupon lane dressing is applied at the rear of the machine utilizing a dressing dispensing head that, like the cleaning liquid dispensing head, reciprocates transversely of the lane to dispense dressing in a pattern preselected by the operator.

Description:
TECHNICAL FIELD 
   The present invention relates to bowling lane maintenance machines and, more particularly, to the cleaning mechanism of such machines used to remove dirt, grime and old lane dressing from the surface of the lane before re-applying conditioning dressing thereto. 
   BACKGROUND AND SUMMARY 
   Lane maintenance machines that travel up and down the length of a bowling lane removing surface grime and old lane dressing are well known in the art. Some of such machines are combination units which clean the lane in the front half of the machine and apply a fresh film of lane dressing to the lane in the rear half. Other machines are essentially single purpose machines capable of only cleaning the lane or applying the lane dressing. Typically, in machines having a cleaning function, a cleaning liquid is applied and then quickly removed through the use of a vacuum squeegee pickup head and sometimes also a wiping cloth immediately ahead of the squeegee. 
   Typically, the cleaning liquid is applied using fixed position, pressurized spray nozzles that atomize the liquid and spray it onto the lane surface ahead of the machine. Examples of that type of cleaning system are disclosed in prior U.S. Pat. Nos. 5,729,855 and 6,615,434 owned by the assignee of the present invention. While pressurized, fixed position spray nozzle systems have performed well over the years, they also have certain drawbacks. 
   For example, the pressurized spray nozzles sometimes drip between spray pulses and at other times, necessitating contrivances to catch and contain such drips. Furthermore, overspray can be a problem wherein the airborne spray droplets are carried by air currents onto adjacent gutters and other structure that must be separately cleaned and maintained from time-to-time. In some establishments having significant air currents, the overspray may even carry into adjacent lanes that have just been cleaned and conditioned. 
   The present invention provides a solution to problems associated with conventional, fixed position pressurized spray systems. In the present invention, instead of relying only on one or more pressurized nozzles to spray cleaning liquid into the air and allow it to settle onto the lane surface in front of the machine, at least one reciprocating dispensing head is positioned close to the lane surface and travels back and forth across the path of travel of the machine while dispensing a highly controlled volume of cleaning liquid directly onto the surface. The position of the dispensing head as it moves across the width of the lane can be accurately coordinated with the position of the machine along the length of the lane to precisely start and stop liquid flow and produce a predetermined pattern of applied liquid. Board-by-board precision is achievable with this type of system. 
   Preferably, a positive displacement pump such as a peristaltic pump is utilized to supply cleaning liquid to the dispensing head in successive uniform increments, producing a precisely metered quantity of the liquid. In one form of the invention, the cleaning liquid is not atomized, but rather issues from the dispensing head in a coherent stream to produce a bead of cleaning liquid on the lane surface. In another form of the invention, each increment of liquid is atomized or diffused into small droplets at the point of discharge to cover a larger surface area of the lane. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a left front perspective view of a maintenance machine embodying the principles of the present invention with its top cover removed to reveal internal details of construction; 
       FIG. 2  is a right rear perspective view of the machine; 
       FIG. 3  is a right front perspective illustration of the cleaning system of the machine and its relationship to certain other components; 
       FIG. 4  is a left rear perspective illustration of the cleaning system and related components; and 
       FIG. 5  is a right side elevational view of the machine with the near sidewall thereof removed to reveal internal details of construction. 
   

   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 machine  10  illustrated in the drawings is similar in many respects to the machine disclosed in U.S. Pat. No. 5,729,855. Accordingly, the &#39;855 patent is incorporated herein by reference. In view of the full disclosure in the &#39;855 patent of the construction and operation of the lane machine, the construction and operation of the machine  10  will be described only generally herein. 
   The machine  10  has a cleaning system denoted broadly by the numeral  12  and located generally in the front of the machine. A dressing application system is denoted broadly by the numeral  14  and located generally in the rear portion of the machine. These two systems perform their functions as the machine travels up and down the lane through the provision of lane-engaging drive wheels  16  and  18  fixed to a transverse shaft  20  that is powered by a drive motor  22  and a chain and sprocket assembly  24 . 
   The dressing application system  14  includes an applicator roll  26  disposed for engaging the lane surface, a reciprocating dressing dispensing head  28  that travels back and forth across the width of the lane above roll  26 , and a brush assembly  30  between roll  26  and dispensing head  28  for receiving dressing from head  28  and delivering it to roll  26 . Details of the construction and manner of use of brush assembly  30  are disclosed in co-pending application Ser. No. 10/791,413 filed Mar. 2, 2004, and titled “Strip Brush Bowling Lane Dressing Application Mechanism”, which is incorporated herein by reference. Dressing application system  14  additionally includes a reservoir  32  and a positive displacement pump (not shown) for supplying dressing from reservoir  32  to dispensing head  28 . 
   Dressing dispensing head  28  is mounted for reciprocation along a transverse guide track  34  extending between the sidewalls of the machine. An endless drive belt  36  is secured to head  28  and has its opposite ends looped around a pair of pulleys  38  and  40 , the pulley  40  being operably coupled with a reversible motor  42  to provide driving power to belt  36  and thus propel dispensing head  28  along track  34 . A pair of sensors  44  and  46  adjacent opposite ends of the path of reciprocal travel of dispensing head  28  are operable to sense the presence of dispensing head  28  as it reaches one limit of its path of travel so as to signal the motor  42  to reverse directions and drive dispensing head  28  in the opposite direction along track  34 . 
   The pulley  38  is fixed to a long fore-and-aft extending shaft  48  disposed just outboard of the right sidewall of the machine. Near its rear end, just forwardly of pulley  38 , shaft  48  is provided with a notched wheel  50  whose rotation is sensed by a sensor  52 . An output from sensor  52  may be sent to the control system of the machine (not shown) for the purpose of determining the precise location of the dressing dispensing head  28  across the width of the machine and the bowling lane. Such location is coordinated with a particular lane dressing pattern that has been programmed into the control system of the machine so that dressing dispensing head  28  may be actuated to precisely dispense dressing at predetermined locations along its path of reciprocation. Distance down the lane is determined by a pair of lane-engaging wheels  53  ( FIGS. 3 ,  4  and  5 ) located just in front of the rear wall of the machine. Wheels  53  are fixed to a common cross shaft  54  that rotates a notched wheel  55  ( FIG. 4 ) via a chain drive  56  ( FIG. 3 ). The number of revolutions of notched wheel  55  is detected by a sensor  57  ( FIG. 4 ) that sends a signal to the control system of the machine. 
   The cleaning system  12  includes one or more cleaning liquid dispensing heads  58  that reciprocate across the path of travel of the machine as it moves along the lane. While system  12  may also include one or more pressurized spray nozzles as in conventional machines, in a preferred embodiment no such conventional spray nozzles are utilized. In the particular embodiment disclosed herein, only a single dispensing head  58  is utilized, such head  58  traveling essentially the full transverse width of the machine to the same extent as the dressing dispensing head  28 . 
   Dispensing head  58  includes a vertically disposed, depending discharge tube  60  provided with a tip  62  that is located close to the lane surface. In one form of the invention, tip  62  is not in the nature of an atomizing nozzle but is instead configured and arranged to emit liquid in a fairly coherent stream so that a bead of cleaning liquid is laid down on the lane surface. One suitable tip  62  for carrying out this particular non-atomizing function is available from the Value Plastics Company of Fort Collins, Colo. as part number VPS5401001N. Other types of tips (not shown) that atomize, breakup or diffuse liquid supplied to the tip may also be utilized where broader surface area coverage by the cleaning liquid is desired. In either case, tip  62  is preferably provided with an internal check valve (not shown). 
   Cleaning system  12  further includes a guide track  64  attached to the front wall of machine  10  that slidably supports dispensing head  58  for its reciprocal movement. Track  64  extends across substantially the entire width of machine  10  to the same extent as the track  34  associated with dressing dispensing head  28 . An endless drive belt  66  is attached to dispensing head  58  for providing reciprocal drive thereto, the belt  66  at its opposite ends being looped around a pair of pulley wheels  68  and  70  respectively. 
   Although pulley  68  may be driven in a number of different ways, including by its own separate drive motor, in a preferred form of the invention pulley  68  is fixed to the forward most end of shaft  48  from pulley  38  so that both dispensing heads  28  and  58  are driven by the same reversible motor  42 . Consequently, both dressing dispensing head  28  and cleaning liquid dispensing head  58  are reciprocated simultaneously by motor  42  when the latter is actuated. However, it will be noted that dressing dispensing head  28  and cleaning liquid dispensing head  58  reciprocate in mutually opposite directions due to the fact that dressing dispensing head  28  is secured to the upper run  36   a  of its drive belt  36  while cleaning liquid dispensing head  58  is secured to the lower run  66   b  of its drive belt  66 . 
   Cleaning system  12  further includes a cleaning solution reservoir  72  at the rear of machine  10 . A supply line  74  leading from reservoir  72  is coupled in flow communication with a peristaltic pump  76  driven by a chain and sprocket assembly  78  operably coupled with the drive shaft  20  of lane drive wheels  16  and  18 . When drive wheels  16  and  18  are turning, pump  76  is operating. It will be appreciated, however, that pump  76  could be driven by its own separate drive motor. An outlet line  80  from pump  76  leads to an inlet port of a solenoid-controlled valve  82  whose operation is controlled by the control system of machine  10 . A supply line  84  leading from one outlet port of valve  82  communicates the valve  82  with discharge tube  60  of dispensing head  58 , while a return line  86  communicates another outlet port of valve  82  with reservoir  72 . Thus, depending upon the position of control valve  82 , cleaning liquid may either be pumped to dispensing head  58  from reservoir  72  or by-passed back to reservoir  72  via return line  86 . Because pump  76  is preferably a peristaltic pump, it supplies liquid to dispensing head  58  in constant volume slugs or squirts that enable the cleaning liquid to be very precisely and accurately metered onto the lane surface. Furthermore, it permits the supply of liquid to dispensing head  58  to be essentially instantaneously stopped and started, which, in conjunction with control valve  82 , affords precise, board-by-board control over the pattern of cleaning liquid applied to the lane surface by dispensing head  58 . 
   Cleaning system  12  additionally includes a wiping assembly  88  immediately behind cleaning liquid dispensing head  58 . Assembly  88  includes a web  90  of soft material such as duster cloth looped around a lower compressible back-up member  92  in the nature of a roller that extends across the full width of the machine. Cloth  90  is stored on a roll  94  and is paid out at intervals selected by the operator and taken up by a take up roll  96 . Wiping assembly  88  is similar in principle to the corresponding wiping assembly disclosed in U.S. Pat. No. 6,615,434, which patent is hereby incorporated by reference into the present specification. 
   A further component of cleaning system  12  comprises a vacuum pickup head  98  located behind wiping assembly  88 . Vacuum pickup head  98  extends essentially the full width of machine  10  and includes a pair of flexible, squeegee-type blades  100  and  102  that assist in picking up the thin film of cleaning liquid left on the lane surface after the wiping assembly  88  has acted upon the liquid. A large vacuum hose  104  leads from pickup head  98  to a holding tank  106  for storing liquid picked up by head  98 . Vacuum pressure within holding tank  106  is obtained by means of a suction fan (not shown) coupled with tank  106 . 
   OPERATION 
   In use, machine  10  is energized and controlled through the use of a user interface panel  108  located adjacent the right rear corner of the machine. Using interface panel  108 , any one of a number of different patterns may be selected for applying cleaning liquid to the lane surface and for the application of dressing. Details of the oil pattern application using the dressing dispensing head  28  are described in the incorporated U.S. Pat. No. 5,729,855. 
   With respect to cleaning operations, as machine  10  travels along the lane surface the cleaning liquid dispensing head  58  reciprocates back and forth along its track  64  across the full width of the lane. Depending upon the distance down the lane as detected by the lane distance sensor  57  and the position of the dispensing head  58  across the width of the lane as detected by the transverse position sensor  52 , control valve  82  allows cleaning liquid from constantly operating pump  76  to be squirted onto the lane surface through the outlet tube  60  and tip  62  of dispensing head  58 . Although it is contemplated that dispensing head  58  may dispense cleaning liquid to the lane across the full width of the lane, it is also within the scope of the present invention to have cleaning liquid applied on a board-by-board basis for selective stripping or cleaning of the lane surface. The check valve (not shown) within tube  60  or tip  62  instantly closes the discharge path for cleaning liquid from head  58  when control valve  82  is shifted to a non-dispensing position. The check valve thus prevents leakage from dispensing head  58  during periods of non-use and provides a sharp demarcation between the presence and absence of cleaning liquid on the lane surface. 
   Cleaning liquid deposited by head  58  is immediately wiped into a thin film by cloth  90  looped around the backup roll  92  of wiping mechanism  88 . While much of the liquid and oil and dirt are removed by cloth  90 , a thin film remains, and this is engaged by the squeegees  100  and  102  of vacuum pickup head  98 . Pickup head  98  thus lifts all remaining moisture, oil and grime from the lane surface and deposits it in the holding tank  106 . Finally, as the rear of the machine passes over the cleaned region, the lane dressing is applied by applicator roll  26  in the pattern selected by the operator. 
   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.