Abstract:
A fluid dispensing device for engine lubrication and/or suspension component maintenance delivers fluid under positive pressure from a remote storage reservoir via a positive displacement pump. Fluid is dispensed in controlled amounts through flexible conduit directly into the fluid cavity of the engine, suspension component or the like. Fluid volume is controlled by internal logic and input from the user via an external selection switch. The apparatus utilizes 12VDC power and compressed air supply. The apparatus has signal indication for both power status and operational status. A method of using the device for to pre-lubricate an engine prior to start-up is also disclosed.

Description:
CROSS-REFERENCE TO RELATED APPLICATION  
       [0001]     This application claims priority to U.S. Provisional Application Ser. No. 60/694,041, filed Jun. 24, 2005. 
     
    
     STAFEMENT OF FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT  
       [0002]     Not applicable.  
       BACKGROUND OF THE INVENTION  
       [0003]     The present invention relates generally to lubrication of mechanical components, and more particularly, to an apparatus and method for delivering lubrication to mechanical components, such as engines and vehicle suspension systems.  
         [0004]     Aftermarket components are commonly installed on vehicles, for example motorcycles, to enhance appearance and performance of the vehicles. These components are installed either by the end user or by service shop technicians. Many of these components are shipped “dry” and require fluid fill prior to use. The components, particularly internal combustion engines, may be pre-lubricated during assembly, yet the fluid volumes of the shipped items may not be sufficient for operation.  
         [0005]     In transition from shipped component to operational engine, the on-boarcl oil pump is required to draw lubricant from the sump, pump it through internal passages until fluid is delivered throughout the engine and then return it to the sump. This process must occur for engine lubrication to reduce contact of internal components and may take several revolutions of the engine crankshaft assembly to complete. During these revolutions, internal components are at high risk for wear. Such “start-up” wear can contribute to premature engine failure and costly repair.  
         [0006]     Engine lubricants have been designed to resist “bleed down”, or return to sump through internal passages. Lubricants are designed such that the bleed-down period of fluids in commuter vehicles is longer than the intermittent use interval. When a vehicle is not operated for awhile, the lubricant is designed to cling to internal components as to reduce wear on the pending start-up.  
         [0007]     A need therefore exists for an improved system to deliver lubricant to the fluid cavities of mechanical components, particularly the internal cavities of assembled engines to avoid wear damage to non-lubricated parts occurring at start-up or following periods of extended non-use.  
       SUMMARY OF THE INVENTION  
       [0008]     In view of the problems associated with proper lubrication levels at engine start-up, the present invention provides a tool for pre-lubrication of mechanical components, particularly engines that are either new, shipped “dry” or partially dry, or have been un-used for extended intervals. The positive pressure output of the apparatus will ensure lubricant dispersion throughout the internal cavities of the components.  
         [0009]     It is an object of the present invention to disperse lubricant throughout the internal cavities of the components via pressurized positive displacement. It is another object of the invention to assist the user in detecting possible sources of lubricant leakage. It is yet another object of the invention to utilize readily available 12VDC power and compressed air in a rugged self-contained device to accomplish dispersion of desired fluid. These and other objectives are met by the dispensing device of the present invention.  
         [0010]     Specifically then, in one aspect the present invention provides a device for delivering lubricant from a reservoir to a fluid cavity of a machine component. The device includes an air inlet for receiving working air from a pressurized air source. A fluid metering pump having a working member for metering lubricant from an inlet to an outlet is air actuated via the working air acting on the working member. An air valve in communication with the air inlet and the pump has a valve member movable to control flow of the working air from the air inlet to the pump. An electronic control controls the air valve such that a prescribed volume of lubricant is metered from the device by the pump.  
         [0011]     The device is preferably portable, having a small housing containing the pump, air valve, electronic control. A small lubricant reservoir can be mounted to the housing so that an internal volume of the reservoir is in communication with an inlet of the pump.  
         [0012]     The pump can be a positive displacement pump and the working member can meter a volume of lubricant from the pump per stroke. The electronic control can then operates the pump for a pre-scribed stroke count so as to meter a prescribed volume of lubricant to the fluid cavity. The prescribed volume is selected according to a fluid capacity of a volumetric capacity in the fluid cavity. The user can use a selector to set the stroke count.  
         [0013]     The air valve can be a three-way valve having a valve member movable to a first position in which working air can pass from the air inlet to the pump, a second position in which the working air is blocked from passing from the air inlet to the pump, and a third position in which working air can pass from the pump to an exhaust port of the valve.  
         [0014]     The device can include a gauge coupled to the outlet of the pump. An outlet line can be coupled between the pump outlet and the fluid cavity so that the gauge can measure both pump outlet pressure and fluid cavity pressure. The gauge measures pump outlet pressure when the pump is operating and measures fluid cavity pressure when the pump is not operating.  
         [0015]     In yet another aspect the invention provides an engine pre-lubrication system for delivering lubricant to a fluid cavity of an engine prior to initial start-up of the engine. The system includes a positive displacement, air actuated fluid metering pump and an electronic control for controlling an air valve such that a prescribed volume of lubricant is metered from the device by the pump according to a volumetric capacity of the fluid cavity. An outlet line is coupled to the pump outlet and the fluid cavity for dispensing metered lubricant into the Fluid cavity. A pressure gauge is operatively coupled to the pump outlet for measuring pump outlet pressure when the pump is energized and engine fluid cavity pressure when the pump is de-energized.  
         [0016]     In still another aspect, the invention provides a method for pre-lubricating an engine prior to initial start up of the engine using the aforesaid lubrication delivery device. The method includes: supplying lubricant for intake through the pump inlet; supplying pressurized working air to the pump for driving the working member; coupling an outlet line from the pump outlet to a fitting on the engine in communication with a fluid cavity of the engine; and energizing the device to meter a prescribed volume of lubricant to the fluid cavity of the engine.  
         [0017]     The method can further include setting a selector to meter the prescribed volume of lubricant according to a volumetric capacity of the engine fluid cavity, and measuring pump outlet pressure when the pump is operating and measuring fluid cavity pressure when the pump is not operating using a gauge mounted between the pump outlet and the outlet line.  
         [0018]     These and still other advantages of the invention will be apparent from the detailed description and drawings. What follows is a preferred embodiment of the present invention. To assess the full scope of the invention the claims should be looked to as the preferred embodiment is not intended as the only embodiment within the scope of the invention. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0019]      FIG. 1  is a perspective view of a pressurized lubricant delivery device according to the present invention;  
         [0020]      FIG. 2  is a front plan view thereof;  
         [0021]      FIG. 3  is a perspective view thereof shown without a housing and outlet line;  
         [0022]      FIG. 4  is a schematic sectional view showing the air and fluid flow paths of the device; and  
         [0023]      FIG. 5  is a sectional view taken along line  5 - 5  of  FIG. 4  through a three-way air valve component of the device.  
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0024]      FIG. 1  shows a preferred version of a lubricant delivery device  10  according to the present invention. The device can be used to automatically meter a predetermined level of lubricant to the fluid lubricant cavity of a machine component. In one preferred application, the machine component can be an internal combustion engine, particularly one that has not undergone initial start-up or has not been operated for an extended period. The device can thus be used to pre-lubricate the engine to a full operational level so as to lubricate, and thus prevent premature wear on, internal working components of the engine such as the pistons and cylinders, that would otherwise be subjected to a non-lubricated interface until full engine compression was established and lubricant was delivered up from the sump of the engine. Full lubrication of the engine at start-up without pre-lubrication can take 300 rotations of the crankshaft (and thus 600 rotations of the camshaft) or more. The resulting wear on the finely machined parts can reduce the engine life by 30,000 miles or more in a typical twin-cylinder motorcycle. Using the present invention to pre-lubricate the engine can prevent this wear and prolong engine life accordingly.  
         [0025]     It is important to note that while the device can be used advantageously for engine pre-lubrication applications and will be described in that context herein, the device can be used to dispense undefined or pre-metered lubricant to any machine component. An example of another such machine component is the suspension “forks” of a motorcycle.  
         [0026]     With reference to  FIGS. 1-3 , the components and features of the device  10  will now be described in detail. The device  10  is contained in a portable housing  12 , with a removable front access panel  14 , defining a sealed interior chamber where the working components of the device are mounted. These include a fluid metering pump  16 , an air valve  18  and an electronic control  20 . A fluid reservoir  22  mounted to the top of the housing  12  so that its filler cap  24  faces upward. One side of the housing  12  has an input bulkhead connections  26  and  28  for power and pressurized air, respectively, as well as a selector switch  30 , momentary button  32  and indicator light  34 , which can be a suitable light emitting diode visually indicating the energized state and operational state of the device  10 . The power input connection  26  allows for connection of a wiring harness  36 . The electronic control  20  operates on standard 12 VDC power so that the wiring harness  36  can have clamps  38  for quickly connecting to the terminals of a standard vehicle battery. The air input connection  28  allows for connection of an air line from a compressor (not shown). The opposite side of the housing  12  has a bulkhead connection  40  to which a T-fitting  42  connects for connecting a liquid pressure gauge  44  and via a tube compression fitting  48  a flexible fluid line  46  having an end fitting  50  for connection to a fitting of the engine leading to the fluid cavity therein (not shown). As will discussed below, the gauge  44  provides for quick verification of both the dispensed lubricant pressure as well as engine fluid cavity pressure.  
         [0027]     With reference to  FIGS. 3-5 , the metering pump  16  is a pneumatically-driven, spring-return positive displacement piston pump, such as that commercially available as model B-3162-401 from Oil-Rite Corporation, of Manitowoc, Wisconsin. The metering pump  16  has a 9 to 1 compression ratio and has a 1,000 psi maximum rating. The metering pump  16  has a fluid inlet  52  that is coupled to the reservoir  22  via a threaded bulkhead connection  54 , and a fluid outlet  56  coupled to the connection  40  via a compression tube fitting  58  and line  60 . A piston  62  reciprocates inside the metering pump  16  to meter a dose of lubricant of a prescribed volume, such as 0.12 cubic inches, from the fluid outlet  56  per stroke cycle. The prescribed volume is adjustable by volumetric adjustment nut  64  at the back of the metering pump  16  that adjusts the initial piston position. Double check valves  66  and  68  are included at the outlet side of the metering pump  16  upstream from the pressure gauge  44  for maintaining pump integrity by preventing backflow when the system is pressurized from the engine cavity, while permitting the gauge to sense engine cavity pressure.  
         [0028]     The piston  62  is driven by the pressurized air via a suitable air line connected to connection  28 . Connection  28  is connected to an inlet  70  of the air valve  18  via line  72  and fitting  74 . An outlet  76  of the air valve  18  is connected via fitting  76 , line  78  and fitting  80  to a pump air inlet  82  of the metering pump  16 , which leads to the air-only side of the piston chamber within the metering pump  16 . Pressurized air, typically at shop compressor pressures of 40-120 psi, entering the pump air inlet  82  works against an enlarged head  84  of the piston  62  to drive it in a forward axial direction against a return spring  86 , which returns the piston  62  to its initial position in the absence of the pressurized air.  
         [0029]     The air valve  18  regulates the flow of the pressurized air to the metering pump  16 . The air valve  18  is preferably a three-way electric solenoid valve, such as that commercially available as 35A-AAA-DFM-1BA, from MAC Valves, Inc. of Wixom, Mich. The air valve  18  has an electromagnet arrangement (not shown) that drives a spool  90  to open and close the pathway from the inlet  70  to the outlet  76  and to an exhaust port  92  having fitting  94 . The spool  90  is thus movable to an initial, de-energized position in which air cannot pass from the inlet  70  to the outlet  76 , an energized position in which air can pass from the inlet  70  to the outlet  76 , and an intermediate position in which air can pass from the outlet  76  to the exhaust port  92  to relieve back pressure in the metering pump  16 , thereby allowing the return spring  86  therein to reset the piston  62  at the end of each compression stroke.  
         [0030]     Operation of the air valve  18  is controlled through logic control by the electronic control  20 . The electronic control  20  is a programmable relay of the type commercially available as the Crouzet Millenium II+, from Crouzet of Coppell, Tex. The electronic control  20  “sees” user input signals from the momentary button  32  and the selector switch  30 . In response to the input signals, the electronic control executes a repeat cycle timer operation to cycle the air valve  18  through the three positions of the spool  90  mentioned above, which in turn will activate and cycle the piston  62  in the metering pump  16  to begin metering lubricant. The cycle timer will continue for a period, for example 300 to 500 cycles, associated with the selector input signal. Thus, because the per stroke volumetric dosing of the metering pump  16  is known, the overall volume of lubricant dispensed during the period of operation of the cycle timer will be at a prescribed volume. This overall volume can be selected according to the capacity of all or part of the engine fluid cavity. Thus, as one example, the volumetric output can be set according to the displacement size of the engine, and the selector switch  30  can then be adjusted to correspond to different engine displacement volumes.  
         [0031]     More specifically, the user will select the desired fluid dispensing state from the selection switch  30  and depress the momentary button  32  for initiation of that selection. The indicator light  34  will illuminate when power is connected to the device  10 , and the LED will illuminate intermittently when the unit is in dispensing mode. The selector switch  30  can also be moved to an “OFF” position. Depressing the momentary button  32  when the selector switch  30  is in the OFF position will terminate the fluid dispensing cycle. Other selection can be provided, with each selection position effecting a certain fluid dispensing state. For example, selections can be dedicated for priming/purging the system volumes, specific cavity fills, continuous fluid dispensing and fluid dispensing cycle termination.  
         [0032]     To operate the device  10 , the user supplies lubricant to the reservoir  22  via the opening covered by the hinged fill cap  24 . The user attaches an fitting  50  at the free end of the outlet line  46  to the fitting on the engine to create a fluid path to the fluid cavity. The user connects the apparatus to a pressurized air source via a line connected to the air connection  28  and to a 12VDC power source via the wiring harness  36  and clamps  38  (if using a battery) connecting to connection  26 . Connecting the device  10  to power activates the indicator light  34 . The user selects the desired fluid dispensing cycle via the selector switch  30 . The user then depresses the momentary button  32  to initiate a cycle. The device  10  begins to cycle through internal logic, recognizing the user switch input and initiating pre-programmed cycling of the air valve  18 , to drive the metering pump  16  to meter lubricant from the reservoir  22 . The metering pump  16  doses positively displaced volumes of lubricant to the engine fluid cavity through the outlet line  46  and fitting  50 . The pressure gauge  44  will indicate fluid pressure, and the indicator light  34  will flash. The indicator light  34  will illuminate steadily when the timer cycle is completed, at which point the metering pump  16  will stop and the check valves  66  and  68  will close. The gauge  44  can sense pressure in the engine fluid cavity while the outlet line  46  is connected to the engine and the engine is operating. After a dispensing cycle is completed, the user can select an additional dispensing cycle via the selector switch  30 , or terminate power by disconnecting the wiring harness  36 .  
         [0033]     It should be appreciated that a preferred embodiment of the invention has been described above. However, many modifications and variations to the preferred embodiment will be apparent to those skilled in the art, which will be within the spirit and scope of the invention. Therefore, the invention should not be limited to the described embodiment. To ascertain the full scope of the invention, the following claims should be referenced.