Abstract:
In various embodiments, the invention provides a lubricator comprising a housing defining, a main lubricant chamber adapted to contain a fluid lubricant. A piston pump in fluid communication with the main lubricant chamber may be adapted to be driven to discharge the lubricant from a pump changer through a lubricant outlet in the housing. A check valve may be mounted on the lubricant outlet, to check the discharge of lubricant from the lubricator. The lubricator may include a motor having a drive shaft adapted to rotate a swash plate to act as a cam to drive reciprocating motion of the pump piston in the pump chamber. The drive shaft may be in axial alignment with the piston, the swash plate being set obliquely on the drive shaft to revolve when the motor is activated to give reciprocating motion to the piston in a direction parallel to the driven shaft. The piston may be biased in the pump chamber against the swash plate, so that the swash plate rides on the piston.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This U.S. National Stage of Patent Cooperation Treaty Application Serial No. PCT/CA2005/000705 filed May 6, 2005 claims the benefit of the filing date of prior filed, U.S. Provisional Application Ser. No. 60/568,267 filed on May 6, 2004. 
    
    
     FIELD OF THE INVENTION 
     The invention relates to methods and apparatus for automatic lubrication of machinery, particularly bearings, that have fittings thereon adapted to receive a quantity of grease or similar lubricant, and more specifically to methods and apparatus that involve a selectable scheduling of lubrication and the active transport of a lubricant, especially by a cam-pump device, that will then inject such lubricant through such fittings into particular machinery that has been connected thereto. 
     BACKGROUND OF THE INVENTION 
     Lubricators that utilize compressed air, compressed springs, motor driven jack screws, augers or a gas generating cartridge as a driving force to eject lubricant into a machine are known in the prior art. For example, U.S. Pat. No. 4,023,648 to Orlitzky et al. describes a lubricant applicator that electrolytically generates a gas as a driving means to force lubricant out of a chamber into a bearing fitting. U.S. Pat. No. 4,671,386 to Orlitzky describes an applicator in which the required pressure is delivered by a bellows. Automatic control of the lubricating process is shown in U.S. Pat. No. 6,408,985 to Orlitzky et al., which describes a programmable, electrical motor-driven lubricator that in different embodiments forces lubricant from a chamber by the operation of a gear-driven or lever-driven piston, or by a bellows. U.S. Pat. No. 5,732,794 to Orlitzky et al, describes an automated lubricator which is microprocessor controlled and can be programmed to deliver lubricant to a bearing or the like at selected intervals. Operation of the lubricator rests upon the use of a minor pressure imposed by a spring to force lubricant into the threads of an auger, so that rotation of the auger by a motor controlled by the microprocessor then dispenses the lubricant while at the same time providing a mixing action to the lubricant. 
     There remains a need for portable lubricators capable of supplying a quantity of lubricant quickly, and capable of maintaining a controlled quantity of lubricant over a range of back pressures and ambient temperatures. In some devices, if the back pressure is too high, or the temperature is too low, substantial time may elapse before the lubricant reaches the machinery intended to be lubricated, such as a bearing, and the latter may then become starved for lubricant and suffer damage accordingly. In some gas generating cells, for example, it may take several days to overcome a line resistance of 15 psi before the lubricant actually reaches the point of lubrication. Conversely, under high temperature conditions there is the opposite danger of overlubricating which can also be damaging. 
     SUMMARY OF THE INVENTION 
     In various embodiments, the invention provides a lubricator comprising a housing defining a main lubricant chamber (or alternative means for containing a fluid lubricant). The lubricant chamber may be adapted to contain a fluid lubricant. The housing may have a lubricant outlet for discharging the lubricant from the lubricator. The lubricator may include a piston pump in fluid communication with the main lubricant chamber (or alternative means for pumping the lubricant in fluid communication with the main lubricant chamber). The piston pump may include a pump chamber adapted to receive lubricant from the main lubricant chamber. The lubricator may include a main chamber piston biased in the housing to urge the lubricant from the main lubricant chamber into the pump chamber. The piston pump may further include a pump piston adapted to be driven to discharge the lubricant from the pump chamber through a lubricant outlet in the housing. A check valve may be mounted on the lubricant outlet, to check the discharge of lubricant from the lubricator when the piston pump is not driven. The lubricator may include a motor for driving the piston pump (or alternative means for driving the piston pump). The motor may have a drive shaft adapted to rotate a swash plate to act as a cam to drive reciprocating motion of the pump piston in the pump chamber. The drive shaft may be in axial alignment with the piston, the swash plate being set obliquely on the drive shaft to revolve when the motor is activated to give reciprocating motion to the piston in a direction parallel to the drive shaft. The piston may be biased in the pump chamber against the swash plate, so that the swash plate rides on the piston. 
     Electronic controls may be provided in some embodiments for regulating the activation of the motor to control the discharge of the lubricant from the lubricator (or alternative means for regulating the discharge of the lubricant from the lubricator). The electronic controls may include an input for setting the rate of discharge of the lubricant from the lubricator. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a cross-sectional drawing of a lubricator in vertical elevation. 
         FIG. 2A  shows a piston pump of the invention broken away in vertical cross section. 
         FIG. 2B  shows an alternate piston pump of the invention broken away in vertical cross section. 
         FIG. 2C  shows an alternate embodiment of a drive shaft swash plate assembly of the invention, broken away in vertical cross section. 
         FIG. 2D  shows an additional alternate embodiment of a drive shaft swash plate assembly of the invention, broken away in vertical cross section. 
         FIG. 3  is a schematic diagram of one embodiment of a circuit on circuit board providing electronic controls for the lubricator of the invention. 
         FIG. 4  is a cross-sectional drawing of an alternate lubricator in vertical elevation, showing multiple lubricant outlets, each comprising a pump element mounted to the pump housing end plate. 
         FIG. 5  is a detailed illustration of one embodiment of a swash plate of the invention. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     In some aspects, the invention comprises a portable device for single point or multiple point lubrication that includes a container having an outlet to be connected to the lubricating system of the machinery; a cam-pump lubricant dispensing mechanism between the container and the outlet. In selected embodiments, such a device may be adapted to produce relatively high pressure using a relatively small DC powered motor using a relatively small current draw (e.g. 0.500 amperes at 6 volts DC for 1200 psi). Selected embodiments may be made to be customer refillable using ordinary grease guns. Exemplary embodiments are illustrated herein, and described below, on the understanding that alternative embodiments may be implemented in keeping with the general scope of the invention as claimed. 
       FIG. 1  depicts in vertical elevation a cross-sectional drawing of a lubricator  10  constructed within a cylindrical, elongated chamber  12 . The lower portion of chamber  12  is generally V-shaped with a hollow interior, thus permitting placement therein of a quantity of grease or lubricant  14 . On the sides of the V-shaped portion there is installed on one side a pressure relief valve  16 , and typically on the opposite site thereof is a zirk or alamite fitting  18  through which lubricant  14  can be introduced into chamber  12 . 
     In the region of lubricator  10  on the side of piston  26  opposite that part of chamber  12  that contains lubricant  14 , DC motor  46  attaches axially to limit switch actuator  73 , which attaches axially to central shaft  34 , which attaches axially to driving pump swash plate/cam  31  and provides the rotational movement of the same so as to rotate driving swash plate/cam  31 . (as hereafter described). Limit switch actuator  73  activates limit switch  72  once per revolution, providing a revolution counter to circuit board  50 . Power for DC motor  46  derives from battery pack  48  constructed of 4 1.5V alkaline batteries sold under the trade name of Energizer Titanium X91 or similar. The batteries are connected in series to provide a nominal 6VDC. The motor, battery pack and limit switch all connect to circuit board  50  via convenient plugs for ease of replacement. Using batteries of the type indicated in battery pack  48 , it is found that in normal operation a chamber  12  containing 125 cc of lubricant  14  can be emptied out two times before battery replacement becomes necessary, i.e. a single battery pack  48  will provide enough power to dispense 250 cc of lubricant. 
     Battery pack  48  is disposed within lubricator  10  in motor housing  62  that extends basket-like on either side of DC motor  46 , and control of DC motor  46  is provided from circuit board  50 , which is conveniently located adjacent thereto. More specifically, circuit board  50  is square shaped and is attached to circuit board housing  74 , disposed so as the DIP switch array  78  is accessible through the opening covered by switchcap  76 . O-ring  75  maintains a tight seal between circuit board housing  74  and switchcap  76 . Circuit board housing  74  is located on the open end of motor housing  62  and held in place by an external toroidal locking rim  67  which threadably attaches to motor housing  62 . O-ring  68  maintains a tight seal between motor housing  62  and circuit board housing  74 . 
     In the region of lubricator  10  which includes DC motor  46 , battery pack  48  and circuit board  50 , chamber  12  is extended outwardly by a circular rim  52  that has external threads  54  and inwardly therefrom a toroidal cavity  56  containing at the bottom thereof an O-ring  58 . Disposing inwardly from toroidal cavity  56  is a toroidal spring  60 , the lower surface of which abuts the upper surface of outer side wall  27  of piston  26 . Motor housing  62  also extends outwardly to the periphery of the interior of lubricator  10  so as to rest upon the upper surface of toroidal spring  60  and compress the same. The strength of toroidal spring  60  is preferably adapted to provide a downward force against piston  26  that will produce a pressure of about 7 psi against lubricant  14 , thereby providing a relatively mild pressure which suffices to force lubricant  14  into pump chamber  44  via pump housing lubricant holes  43 . As hereafter described, it is the downward action of piston pump  32  which actually forces lubricant  14  to be expelled from lubricator  10 , and not any pressure as such on the bulk of lubricant  14 . It may now be noted that motor housing  62  is held in the position aforesaid by an external, toroidal locking rim  66  which threadably attaches to circular rim  52 . 
     Threaded into the bottom end of chamber  12  is an externally threaded pump housing  20 , typically of ½ inch size. The outlet of chamber  12  is externally threaded to ½ inch NPT. Threaded onto the outlet of chamber  12  is check valve assembly  22 , which has ½ inch NPT internal threads and an extension having ¼ inch exterior threads for convenient attachment to a grease fitting on a bearing or the like. Inserted into check valve assembly  22  is check ball  40  which is kept seated by spring  41 , which is kept in place by retainer  42 . 
     Above lubricant  14  is piston  26  having a tubular upwardly extending outer side wall  27  which encircles the interior of chamber  12 , the external periphery of outer side wall  27  being in close contact with the interior surface of chamber  12  and having disposed therein a set of piston o-rings  28  for maintaining a tight seal thereto. Piston  26  is further adapted to accommodate about the central vertical axis thereof a toroidal piston cup seal  30  through the center of which passes a central shaft  34 . Piston cup seal  30  ensures a tight seal between central shaft  34  and piston  26  above lubricant  14 . 
     Attached to central shaft  34  is driving pump swash plate/cam  31  which rides on driven pump piston  32 . Return spring  33  is located between pump housing  20  and pump piston  32 . (as hereinafter described). 
     As shown in greater detail in  FIG. 2A , pump housing  20  further comprises a set of holes  43  therein at points within the region of chamber  12  containing lubricant  14 , which permits passage of portions of lubricant  14  into the pump chamber  44  of pump housing  22 . Rotation of central shaft  34  rotates driving pump swash plate/cam  31 , which causes pump piston  32  to move downwards, compressing spring  33  and transporting such quantity of lubricant  14  that has entered the pump chamber  44  outwardly through pump chamber opening  45 . When the lubricant pressure in the pump chamber opening  45  has overcome the resistance of check ball spring  41 , then check ball  40  moves downward, allowing the lubricant  14  to pass by check ball  40  and into the grease fitting or grease line (not shown) to which check valve assembly  22  has been connected. When piston pump  32  reaches the bottom of its travel, spring  33  is compressed. As driving pump swash plate/cam  31  continues to rotate, spring  33  forces pump piston  32  to move upwards back to its starting location. As it moves upwards, a vacuum is created in pump chamber  44 . When pump piston  32  has cleared pump housing holes  45 , lubricant  14  enters pump chamber  44 . As pump piston  32  moves upward, the pressure in pump chamber  44  decreases, which allows check ball spring  41  to seal check ball  40  into check valve assembly  22 , which prevents grease from returning into pump chamber  44  from the grease fitting, Guide pin  39  travels in a longitudinal motion which prevents pump piston  32  from rotating. O-ring  38  maintains a tight seal between pump housing  20  and check valve assembly  22 . This action repeats itself under control of circuit board  50 . 
       FIG. 2B  shows the an alternate embodiment of the pump. In this embodiment, check ball  40 , spring  41 , and retainer  42  are moved from check valve assembly  22  and installed in the bottom of the pump housing  20 . The operation does not change. Check valve assembly  22  in this embodiment is an adapter with ½ inch NPT internal threads and an extension having ¼ inch exterior threads for convenient attachment to a grease fitting on a bearing or the like. 
       FIG. 2C  shows an alternate embodiment of the driving pump swash plate/cam  31 . This embodiment functions to limit the pressure generated by pump piston  32 . In this embodiment, all functions of lubricator  10  operate as herebefore described. The additional features of the embodiment of  FIG. 2C  operate as follows. As the pressure increases in pump chamber  44 , pump piston  32  requires more force when traveling in a downward action to compress lubricant  14 . When the pressure in pump chamber  44  reaches a specific value (maximum pressure), overpressure spring  37  will start to compress. The maximum pressure is determined by the resistance of spring  37 . When overpressure spring  37  compresses, driving pump swash plate/cam  31  will travel upward into central shaft  34 . Guide pin  36  travels in a longitudinal motion in guide pin slot  35 , which prevents driving pump swash plate/cam  31  from rotating or becoming disconnected from central shaft  34 . When driving pump swash plate/cam  31  travels upward into central shaft  34 , the downward travel of pump piston  32  is reduced, which reduces the pressure developed in pump chamber  44 . This embodiment may also be adapted to provide compensation for expansion or contraction of components due to temperature changes. 
       FIG. 2D  shows an alternate embodiment of the pump. In this embodiment, retainer  47  maintains the position of driving pump swash plate/cam  31  and accurately positions pump piston  32  in relation to the pump housing  20 . Limit switch actuator  73  is modified to allow central shaft  34  to float in/out of actuator  73 , its position determined by the location of the pump assembly  20 . This mechanism may be adapted to provide temperature compensation to maintain consistant pump output over a temperature range. As cylinder  10  stretches in the heat, pump assembly  20  will travel away from actuator  73 , creating a larger gap inside actuator  73  above central shaft  34 . As cylinder  10  compresses when it cools, pump assembly  20  will travel toward actuator  73 , decreasing the gap inside actuator  73 . In this way, pump piston  32  will always remain stable in relation to pump housing  20 . 
       FIG. 4  shows an alternate embodiment of the lubricator. In this embodiment there are multiple lubricant outlets, each consisting of a pump element  174  mounted to the pump housing end plate  172 . For clarity,  FIG. 4  shows only two pump elements, whereas in alternative embodiments there may be a plurality of pump elements of three or more. 
     Threaded onto the outlet of chamber  12  is pump housing  170 . O-ring  38  ensures a tight seal between lubricator  10  and pump housing  170 . Pump housing end plate  172  is attached to the open end of pump housing  170  using threaded screws (or alternative fasteners). O-ring  177  ensures a tight seal between pump housing  170  and pump housing end plate  172 . Pump elements  174  are threaded, or otherwise attached, onto pump housing end plate  172 , Pump elements  174  may for example be selected from commercially available pump elements, comprising a spring loaded piston pump and a check valve. 
     In the embodiment of  FIG. 4 , attached axially to central shaft  34  is the progressive displacement auger  160 . Attached axially to progressive displacement auger  160  is swash plate/cam  162 , and attached axially to swash plate/cam  162  is swash plate locating pin  164 . The bottom end of swash plate locating pin  164  terminates in pump housing end plate  172 . 
     In the embodiment of  FIG. 4 , rotation of central shaft  34  rotates progressive displacement auger  160  which remixes and pushes lubricant  14  from chamber  12  into pump housing chamber  176 , creating a positive pressure in pump housing chamber  176 , helping to ensure that lubricant is available at all times to pump elements  174 . Rotation of central shaft  34  rotates swash plate/cam  162 , which causes pump elements  174  to compress. The compression of pump elements  174  transports lubricant outwardly from pump housing chamber  176  into the grease fitting or grease line (not shown) which is attached to the outlet of pump element  174 . Lubricant is introduced into pump housing chamber  176  and chamber  12  through zirk or alamite fitting  18 . 
       FIG. 3  is a diagram of one embodiment of a circuit incorporated on circuit board  50 . Circuit  100  serves to control the times of dispensation of lubricant by lubricator  10 , i.e. the times of operation of DC motor  46  which causes rotation of central shaft  34  and hence disposition of lubricant as previously described. Since particular embodiments of the invention may be placed in applications that have a wide range of different conditions of back pressure, bearing demands and the like, circuit  100  includes provisions for varying the timing of such lubricant dispensation. 
     Circuit  100  includes switch array  78  and switches  80 - 92  in schematic form. Switch array  78  includes terminals connecting to one side of each of switches  80 - 92 , said terminals on the switch array being respectively numbered  8 - 14  and in circuit  100  all are connected to ground. 
     Circuit  100  further comprises resistor array  104  containing a set of thirteenth-nineteenth resistors  106 - 118 , each of which preferably has a resistance of about 1 MΩ. The sides of switches  80 - 92  opposite their previously noted terminals connecting to ground have external terminals that are numbered on switch array  78  as  7 ,  6 ,  5 ,  4 ,  3 ,  2 , and  1  respectively, and connect therethrough to proximal ends of thirteenth-nineteenth resistors  106 - 118 , respectively. The distal ends of thirteenth-nineteenth resistors  106 - 118  are mutually interconnected and connect also to terminal  18  of microprocessor (MP)  102 , which constitutes the RC0 terminal thereof. 
     Thirteenth-nineteenth resistors  106 - 118  provide a pull-up resistive network for the switch inputs to MP  102 . That is, in addition to the aforesaid connections to thirteenth-nineteenth resistors  106 - 118 , terminals  7 ,  6 ,  5 ,  4 ,  3 ,  2 , and  1 , connect to MP  102  as shown in Table 1. 
     
       
         
               
               
               
               
               
               
               
               
             
           
               
                 TABLE 1 
               
               
                   
               
             
             
               
                 Array 78 
                 7 
                 6 
                 5 
                 4 
                 3 
                 2 
                 1 
               
               
                 MP 102 
                 19 
                 20 
                 21 
                 22 
                 23 
                 24 
                 25 
               
               
                 Input 
                 RC1 
                 RC2 
                 RC3 
                 RC4 
                 RC5 
                 RC6 
                 RC7 
               
               
                   
               
             
          
         
       
     
     In Table 1, the first row represents the terminals of switch array  78 , the second row represents the terminals of MP  102  to which the terminals in the same column of the first row connect, and the third row gives the standard notation for the aforesaid input terminals of MP  102 . 
     MP  102  is preferably an EPROM such as the PIC16C55A manufactured by Microchip Technology Inc., i.e., a known type that can easily be programmed by a person of ordinary skill in the art. The power for MP  102  is provided by a connection to the MCLR input (terminal  28 ) thereof to VDD (as produced in a separate circuit described hereinafter). An oscillator circuit for timing the operation of lubricator  10  is made up of crystal  120  which connects on either side thereof to ground through first and second capacitors  122  and  124  (each about 22 pf) and also on either side thereof to terminals  26  and  27  of MP  102  labeled as “OSC 2 ” and “OSC 1 ”. Crystal  120  is preferably of a low power consumption type, and operates at a frequency of about 32.768 kHz. The RA0 and RTCC connections of MP  102  which are respectively terminals  6  and  1  thereof connect through sixth resistor  126  and then third capacitor  128  to ground. The RA1 terminal of MP  102  (terminal  7 ) connects through seventh resistor  130  to that same third capacitor  128  and thence to ground, and similarly the RA3 terminal of MP  102  (terminal  9 ) connects through fifth resistor  132  through third capacitor  128  to ground. 
     Seventh resistor is preferably a U.S. Sensors thermistor (e.g. of the type 105RG1K), the measured resistance (Rm) of which is used to sense the device temperature on the basis of which the operation of lubricator  10  can be terminated. Seventh resistor  130  constitutes a part of a capacitive charging circuit that also includes sixth resistor  126 , third capacitor  128 , and fifth resistor  132 . Sixth resistor  126  has a small resistance of about 100Ω and serves to limit current through terminal  6  (RA0) of MP  102 . Through terminal  9  (RA3) of MP  102  a reference voltage Vr (e.g. VDD at 3.6 volts) is applied to fifth resistor  132  (Rc) so that third capacitor  128  (about 0.01 uf commences charging to a threshold voltage Vt (e.g. 2.5 volts), and a reference value Tc for the time of charging is stored in the MP  102  memory. Fifth resistor  132  will have a calibration resistance Rc of about 1 MΩ, but in any case Rc cannot exceed the resistance of seventh resistor  130  (i.e. the thermistor). After discharge of third capacitor  128  under the control of MP  102 , reference voltage Vr is applied to seventh resistor  130  and the charging time Tm in passing current through seventh resistor  130  is determined so as to yield the resistance value Rm thereof in accordance with the formula Rm=(Tm/Tc) Rc. On the basis of lookup tables stored in MP  102 , the temperature of seventh resistor  130  can be ascertained, or preferably the temperature dependant Rm value can be used to trigger a selected shut-off of circuit  100 . MP  102  is thus programmed by standard “burn-out” methods such that with the aforesaid resistance and capacitance values so selected, at a temperature of about −10 degrees Celsius seventh resistor  130  will have a resistance value Rm that will disable DC motor  46  run pin  15  (RB5) of MP  102  as discussed below. 
     The further connections of MP  102  that serve to operate DC motor  46  are found at the RB5 terminal thereof (terminal  15 ) which connects through tenth resistor  134  (e.g. 27 kΩ) to the base of third BJ transistor  136 . The collector of third BJ transistor  136  connects to VCC. The emitter of third BJ transistor  136  connects through eleventh resistor  144  (e.g. 100Ω) to the base of forth BJ transistor  140 , while the emitter of forth BJ transistor  140  connects to ground directly. 
     First resistor  150  (e.g. 1 KΩ) connects between Vcc and the collector of BJ transistor  146  of the 2N3904 type and serves as a pull-up resistor. The base of BJ transistor  146  is connected to terminal  17  (RB7) of MP  102  through eighth resistor  145  (e.g. 27KΩ). The emitter of BJ transistor  146  connects to green LED  138  which is connected to ground. Second resistor  149  (e.g. 1KΩ) connects between Vcc and the collector of BJ transistor  148  of the 2N3904 type and serves as a pull-up resistor. The base of BJ transistor  148  is connected to terminal  16  (RB6) of MP  102  through ninth resistor  147  (e.g. 27KΩ). The emitter of BJ transistor  148  connects to red LED  139  which is connected to ground. Under MP  102  program control, the green and red LED&#39;s are used to indicate operation and status conditions of the lubricator  10 . 
     Third resistor  133  (e.g. 10KΩ) connects between MP  102  terminal  13  (RB3), pin  2  of the rotation sensor plug and ground, and is a pull-down resistor. Terminal  14  (RB4) of MP  102  connects to pin  1  of the rotation sensor plug. Limit switch  72  is connected to circuit board  50  via the rotation sensor plug. Forth resistor  135  (e.g. 10KΩ) connects between MP  102  terminal  11  (RB1), terminal  12  (RB2), pin  2  of the empty sensor plug, pin  2  or the remote/serial plug, and ground, and is a pull-down resistor. Terminal  13  (RB3) of MP  102  connects to pin  1  of the empty sensor plug. Terminal  10  (RB0) of MP  102  connects to pin  1  of the remote/serial plug. The remote/serial plug and the empty sensor plugs are used for inputting the status of future signals to the MP  102  microprocessor. 
     In operation, through the internal programming of MP  102 , turning on the MP  102  output RC0 (terminal  18 ) connects any of the switches  80 - 92  which are off to VDD. Any of the switches  80 - 92  which are on connect the input to MP  102  to ground, thereby making the status of switches  80 - 92  inputs to the particular lines of MP  102  (RC1-RC7). This permits an output to be generated on the MP  102  output line RB5 through tenth resistor  134  to the base connection of BJ transistor  136 , turning on BJ transistor  136 . As indicated in Table 2, the specific time periods of such output are in each case determined by the programming of MP  102 . Turning on third BJ transistor  136  will connect VCC to the base connection of fourth transistor  140  through eleventh resistor  144 . Turning on fourth BJ transistor  140  connects motor  46  between VCC and ground, hence DC motor  46  begins operating. Although there are specific time periods shown in Table 2 for emptying lubricator  10  of lubricant  14 , it will be understood that such time periods are arbitrary and can be programmed to have different values as the user of the present invention may desire. 
     
       
         
               
               
               
               
               
               
               
             
               
               
               
               
               
               
               
             
           
               
                 TABLE 2 
               
               
                   
               
               
                 Days to 
                 Switch 
                 Switch 
                 Switch 
                 Switch 
                 Switch 
                 Switch 
               
               
                 Empty 
                 1 
                 2 
                 3 
                 4 
                 5 
                 6 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                 15 
                 ON 
                 OFF 
                 OFF 
                 OFF 
                 OFF 
                 OFF 
               
               
                 30 
                 OFF 
                 ON 
                 OFF 
                 OFF 
                 OFF 
                 OFF 
               
               
                 45 
                 ON 
                 ON 
                 OFF 
                 OFF 
                 OFF 
                 OFF 
               
               
                 60 
                 OFF 
                 OFF 
                 ON 
                 OFF 
                 OFF 
                 OFF 
               
               
                 75 
                 ON 
                 OFF 
                 ON 
                 OFF 
                 OFF 
                 OFF 
               
               
                 90 
                 OFF 
                 ON 
                 ON 
                 OFF 
                 OFF 
                 OFF 
               
               
                 105 
                 ON 
                 ON 
                 ON 
                 OFF 
                 OFF 
                 OFF 
               
               
                 120 
                 OFF 
                 OFF 
                 OFF 
                 ON 
                 OFF 
                 OFF 
               
               
                 135 
                 ON 
                 OFF 
                 OFF 
                 ON 
                 OFF 
                 OFF 
               
               
                 150 
                 OFF 
                 ON 
                 OFF 
                 ON 
                 OFF 
                 OFF 
               
               
                 165 
                 ON 
                 ON 
                 OFF 
                 ON 
                 OFF 
                 OFF 
               
               
                 180 
                 OFF 
                 OFF 
                 ON 
                 ON 
                 OFF 
                 OFF 
               
               
                 195 
                 ON 
                 OFF 
                 ON 
                 ON 
                 OFF 
                 OFF 
               
               
                 210 
                 OFF 
                 ON 
                 ON 
                 ON 
                 OFF 
                 OFF 
               
               
                 225 
                 ON 
                 ON 
                 ON 
                 ON 
                 OFF 
                 OFF 
               
               
                 240 
                 OFF 
                 OFF 
                 OFF 
                 OFF 
                 ON 
                 OFF 
               
               
                 255 
                 ON 
                 OFF 
                 OFF 
                 OFF 
                 ON 
                 OFF 
               
               
                 270 
                 OFF 
                 ON 
                 OFF 
                 OFF 
                 ON 
                 OFF 
               
               
                 285 
                 ON 
                 ON 
                 OFF 
                 OFF 
                 ON 
                 OFF 
               
               
                 300 
                 OFF 
                 OFF 
                 ON 
                 OFF 
                 ON 
                 OFF 
               
               
                 315 
                 ON 
                 OFF 
                 ON 
                 OFF 
                 ON 
                 OFF 
               
               
                 330 
                 OFF 
                 ON 
                 ON 
                 OFF 
                 ON 
                 OFF 
               
               
                 345 
                 ON 
                 ON 
                 ON 
                 OFF 
                 ON 
                 OFF 
               
               
                 360 
                 OFF 
                 OFF 
                 OFF 
                 ON 
                 ON 
                 OFF 
               
               
                 375 
                 ON 
                 OFF 
                 OFF 
                 ON 
                 ON 
                 OFF 
               
               
                 390 
                 OFF 
                 ON 
                 OFF 
                 ON 
                 ON 
                 OFF 
               
               
                 405 
                 ON 
                 ON 
                 OFF 
                 ON 
                 ON 
                 OFF 
               
               
                 420 
                 OFF 
                 OFF 
                 ON 
                 ON 
                 ON 
                 OFF 
               
               
                 435 
                 ON 
                 OFF 
                 ON 
                 ON 
                 ON 
                 OFF 
               
               
                 450 
                 OFF 
                 ON 
                 ON 
                 ON 
                 ON 
                 OFF 
               
               
                 465 
                 ON 
                 ON 
                 ON 
                 ON 
                 ON 
                 OFF 
               
               
                 480 
                 OFF 
                 OFF 
                 OFF 
                 OFF 
                 OFF 
                 ON 
               
               
                 495 
                 ON 
                 OFF 
                 OFF 
                 OFF 
                 OFF 
                 ON 
               
               
                 510 
                 OFF 
                 ON 
                 OFF 
                 OFF 
                 OFF 
                 ON 
               
               
                 525 
                 ON 
                 ON 
                 OFF 
                 OFF 
                 OFF 
                 ON 
               
               
                 540 
                 OFF 
                 OFF 
                 ON 
                 OFF 
                 OFF 
                 ON 
               
               
                 555 
                 ON 
                 OFF 
                 ON 
                 OFF 
                 OFF 
                 ON 
               
               
                 570 
                 OFF 
                 ON 
                 ON 
                 OFF 
                 OFF 
                 ON 
               
               
                 585 
                 ON 
                 ON 
                 ON 
                 OFF 
                 OFF 
                 ON 
               
               
                 600 
                 OFF 
                 OFF 
                 OFF 
                 ON 
                 OFF 
                 ON 
               
               
                 615 
                 ON 
                 OFF 
                 OFF 
                 ON 
                 OFF 
                 ON 
               
               
                 630 
                 OFF 
                 ON 
                 OFF 
                 ON 
                 OFF 
                 ON 
               
               
                 645 
                 ON 
                 ON 
                 OFF 
                 ON 
                 OFF 
                 ON 
               
               
                 660 
                 OFF 
                 OFF 
                 ON 
                 ON 
                 OFF 
                 ON 
               
               
                 675 
                 ON 
                 OFF 
                 ON 
                 ON 
                 OFF 
                 ON 
               
               
                 690 
                 OFF 
                 ON 
                 ON 
                 ON 
                 OFF 
                 ON 
               
               
                 705 
                 ON 
                 ON 
                 ON 
                 ON 
                 OFF 
                 ON 
               
               
                 720 
                 OFF 
                 OFF 
                 OFF 
                 OFF 
                 ON 
                 ON 
               
               
                   
               
             
          
         
       
     
     Although various embodiments of the invention are disclosed herein, many adaptations and modifications may be made within the scope of the invention in accordance with the common general knowledge of those skilled in this art. Such modifications include the substitution of known equivalents for any aspect of the invention in order to achieve the same result in substantially the same way. For example, the circuit board may utilize surface mount devices, one or more extra LED&#39;s to provide additional user information, different microprocessors, or alternate board shapes. Numeric ranges are inclusive of the numbers defining the range. The word “comprising” is used herein as an open-ended term, substantially equivalent to the phrase “including, but not limited to”, and the word “comprises” has a corresponding meaning. As used herein, the singular forms “a”, “an” and “the” include plural referents unless the context clearly dictates otherwise. Thus, for example, reference to “a thing” includes more than one such thing. Citation of references herein is not an admission that such references are prior art to the present invention. Any priority document(s) and all publications, including but not limited to patents and patent applications, cited in this specification are incorporated herein by reference as if each individual publication were specifically and individually indicated to be incorporated by reference herein and as though fully set forth herein. In particular the following documents are hereby incorporated by reference: U.S. Pat. Nos. 4,023,648; 4,671,386; 6,408,985; 5,732,794. The invention includes all embodiments and variations substantially as hereinbefore described and with reference to the examples and drawings.