Abstract:
A fluid dispensing device of the type, including a shut off valve means for controlling fluid flow through the device and an actuating trigger operable to cause the shut off valve to adopt an open position in which fluid can be dispensed from the device and a closed position, a control meter which enables the volume of fluid being disposed to be measured, a latching mechanism operable to hold the shut off valve in the open position and cause the shut off valve to adopt the closed position when the predetermined volume of fluid has been dispensed, and a setting mechanism being operatively connected to the control meter for indicating a predetermined volume of fluid required to be dispensed and indicating when that predetermined volume has been dispensed.

Description:
FIELD OF INVENTION 
   This invention relates generally to fluid dispensing devices for controlling the flow of fluid therefrom and components therefor. 
   BACKGROUND OF INVENTION 
   One particular application of the present invention is in the automotive industry where oil is stored in a bulk tank and supplied to a work area through for example a pipe system and hose reel. The fluid dispensing device permits the amount of oil being dispensed to be controlled. It will be readily apparent to those persons skilled in the art that the dispensing device of the present invention could be used in a variety of applications and as such reference to the aforementioned particular application is not to be taken as a limitation on the scope of the present invention. 
   Fluid dispensing devices for controlling the discharge of fluid are known. Generally such devices include a control valve and meter through which fluid to be dispensed is passed and a display providing a reading of the quantity of fluid dispensed and/or required to be dispensed. In some currently known dispensing devices the required amount of fluid to be dispensed can be indicated on the display. The device can thereafter be activated so that fluid can be discharged from the device until the selected amount of fluid has been discharged. Once this has been achieved the device is adapted so as to stop the flow of fluid being discharged. 
   Known devices include electronic systems by which the quantity of fluid required to be dispensed can be set and subsequently stopped. A problem with electronic systems is that they can be relatively expensive and prone to damage particularly where the environment of use leads to rough handling of equipment. Mechanical systems have also been proposed but these are usually in the form of a settable rotary dial which have a limited accuracy. 
   It is an object of the present invention to provide an improved dispensing device which alleviates one or more of the aforementioned disadvantages. 
   SUMMARY 
   The present invention is concerned with a fluid dispensing device of the type, including a shut off valve means for controlling fluid flow through the device and an actuating trigger operable to cause the shut off valve to adopt an open position in which fluid can be dispensed from the device and a closed position, a control meter which enables the volume of fluid being disposed to be measured, a latching mechanism operable to hold the shut off valve in the open position and cause the shut off valve to adopt the closed position when the predetermined volume of fluid has been dispensed, and a setting mechanism being operatively connected to the control meter for indicating a predetermined volume of fluid required to be dispensed and indicating when that predetermined volume has been dispensed. 
   According to one aspect of the present invention there is provided a setting mechanism suitable for use in a fluid dispensing device of the type described above the setting mechanism including a plurality of display wheels which can indicate the predetermined quantity of fluid to be dispensed. The display wheels are operatively connected to the control meter so that the flow of fluid through the control meter can be displayed on the display wheels. The arrangement is such that when the shut off valve is in the closed position the display wheels can be adjusted to indicate the predetermined quantity of fluid to be dispensed and when the shut off valve is opened the display wheels can indicate when the predetermined volume has been dispensed. The setting mechanism includes a plurality of setting wheels each setting wheel being associated with a respective one of the display wheels, each setting wheel being operatively connectible with the display wheel with which it is associated via a gear train, each setting wheel being mounted for movement between an engaged position and a disengaged position. 
   In the engaged position each setting wheel is operatively connected to the display wheel with which it is associated via the gear train so that rotation of the setting wheel causes rotation of the display wheel with which it is associated. In the disengaged position the setting wheel is disconnected from the display wheel with which it is associated and may be freely rotatable. 
   The setting mechanism may include a support frame to which the setting wheels and display wheels are operatively mounted. 
   Each setting wheel may be operatively mounted to a pivot member which is pivotally connected to the support frame, so that pivotal movement of the pivot member causes movement of the setting wheel between the engaged and disengaged positions. 
   There may further be provided spring means for urging each setting wheel into the disengaged position. The spring means may be in the form of a generally resilient leg on the pivot member. 
   According to another aspect of the invention there is provided a latching mechanism suitable for use in a fluid dispensing device of the type described above either in its broadest form or more specific forms the latching mechanism including a latch setting assembly for setting the actuating trigger of the device so that the shut off valve is in the open position, a trip assembly which is actuatable at a preselected display on the display wheels of the setting mechanism, a first catch assembly operable so as to adopt an engaged position or a disengaged position and arranged such that actuation of the trip assembly causes the first catch assembly to adopt the disengaged position, and a second catch assembly which can adopt an engaged position when the actuator trigger of the device is in an actuating position in which the shut off valve is open, the first catch assembly adopting the engaged position when the actuator trigger is moved to the actuating position. 
   The latch setting assembly may include a setting button mounted on the actuator trigger, and a connector arm operatively connected to the button. 
   The first catch assembly may include a control member which is pivotally mounted to a part of the body portion of the trigger. The control member may include a catch and push element adapted to cooperate with a latch member. The latch member may be in the form of a latching plate pivotally mounted to the housing at a pivot mounting. The catch assembly may include first and second latching sections defined by shoulders formed as edges of apertures in the latching plate. 
   The second catch assembly may include a catch member having a catch thereon which is operatively connected to a trip assembly. A spring may act on the catch member. 
   The trip assembly may include a trip pin actuatable by a boss on one of the display wheel. A coupling member is caused to be moved by the trip pin whereupon it is engaged by an activating projection on another display wheel. 
   The latching mechanism is operable so as to be able to adopt a latched position in which position the valve of the dispensing device is open and a release position in which the valve can return to a closed position. Preferably the trigger can be activated to cause the valve to open whether or not the latch mechanism is in the latched position. 
   To set the latching mechanism the trigger is depressed. This causes rotation of the shaft and cam surface which acts on the valve follower to cause the valve to open. The rotational movement of the trigger body moves the control member into engagement with the latch plate. The latch plate is pivotal about its pivot mounting causing the catch to engage with first latching section on latch plate. At this stage the catch is not engaged with latching section and the trigger can return to its first position under the influence of a spring. 
   To set the trigger it is moved to its second position causing a pivotal movement of the control member and depression of the button causes arm to engage the end of the control member so that the catch engages latching section thereby holding the trigger in the second position. 
   The setting mechanism enables a volume to be set correlating to three display wheels. For example, the device can be set to read tenth increments, unit increments and decade increments. The selected volume is set by pressing and rotating to the selected reading each of the thumb wheels each of which is associated with a respective display wheel. When moved the thumb wheels disengage from the other wheels so that they can be separately set without interference from the other wheels. All wheels can be rotation in both directions. 
   When the trigger is moved to the second position and the latch mechanism set fluid can flow through the meter and the display wheels will rotate counting down towards zero. When the meter reaches zero the valve latch is released and the flow stops. 
   In accordance with other aspects of the present invention there is provided a fluid dispensing device of the type described above. 

   
     BRIEF DESCRIPTION OF DRAWINGS 
     Preferred embodiments of the invention will hereinafter be described with reference to the accompanying drawings, and in those drawings: 
       FIG. 1  is a perspective view of a fluid dispensing device according to the present invention; 
       FIG. 2  is an exploded view of the device shown in  FIG. 1 ; 
       FIGS. 2(   a ) and  2 ( b ) are views from different positions of a connection between part of a setting mechanism and a calibrating gear box which form part of the fluid dispensing device shown in  FIGS. 1 and 2 ; 
       FIGS. 3(   a ) and  3 ( b ) are exploded perspective views of a setting mechanism which forms part of the device shown in  FIGS. 1 and 2 ; 
       FIG. 4  is a detail of part of the setting mechanism shown in  FIG. 3 ; 
       FIG. 5  is a detail of another part of the setting mechanism shown in  FIG. 3 ; 
       FIG. 6  is a different view of that part of the setting mechanism shown in  FIG. 5 ; 
       FIGS. 7 and 8  illustrate a detail of part of the setting mechanism shown in  FIG. 3 ; 
       FIGS. 9 to 13  illustrate another part of the setting mechanism shown in  FIG. 3 ; 
       FIG. 14  is a perspective view of a latching mechanism forming part of the device shown in  FIGS. 1 and 2 ; 
       FIGS. 15 to 18  illustrate how the latching mechanism is triggered; and 
       FIGS. 19 to 23  illustrate the operation of the latching and triggering mechanisms. 
   

   DETAILED DESCRIPTION 
   Referring to  FIGS. 1 and 2  there is shown a fluid dispensing device  10  which includes a main body  12  having a handle  14 , an inlet  15  which is connectible to a hose (not shown) from which fluid is delivered to the device and an outlet  16  to which a nozzle (not shown) can be attached for discharging fluid from the device  10 . The device further includes a trigger  17  operable so that it can adopt first and second positions which causes a valve  18  ( FIG. 19 to 23 ) to open or close. With reference to  FIGS. 19 to 23  the trigger includes a body portion  26  to which a pivot shaft  27  is mounted. The pivot shaft  27  includes cam section  28  in the form of a flat side face on the pivot shaft  27  which acts against an extension or follower  19  of the valve  18 . A spring  29  urges the valve  18  into its closed position. The trigger is pivotally movable from the first position ( FIG. 19 ) in which the valve  18  is closed to the second position ( FIG. 20 ) in which the valve  18  is open. To open the valve  18  the cam section  28  acts on the free end of the valve extension  19  when the trigger  17  moves into the second position (see  FIG. 20 ). A spring (not shown) urges the trigger  17  into the first position. In use when the trigger  17  is in the second position fluid can flow through the device  10  from the inlet  15  to the outlet  16 . The device further includes a constant volume control meter  20  which measures the flow of fluid therethrough, a calibrating gear box  22  operatively connected to the control meter  20  and a setting mechanism  50  which can be set a predetermined volume so that the valve  18  will be closed upon actuation of a latching mechanism which is triggered when the predetermined volume of fluid has passed through the device. The setting mechanism is housed within a casing  24  and a protective rubber boot (not shown) surrounds the main body of the device. 
   The present invention is concerned in particular with the improved setting mechanism and/or the associated latching mechanism. There are several new and distinct aspects of these mechanisms which may constitute separate and distinct inventions in their own right. 
   The Setting Mechanism 
   Referring to  FIGS. 3(   a ) and  3 ( b ) of the drawings there is shown a setting mechanism  50  for setting and displaying a selected volume of fluid to be dispensed through the meter  20 . The setting mechanism  50  comprises first, second and third setting wheels  52 ,  54  and  56 . Each setting wheel is mounted for movement between an engaged position and a disengaged position. In the engaged position each setting wheel is operatively connected to a respective one of the display wheels  53 ,  55  and  57  with which it is associated via individual gear trains. In the particular application described the first display wheel  53  displays tenths, the second display wheel  55  displays units, and the third display wheel  57  displays decades, in relation to volume units of fluid dispensed through the control meter  20 . The various components of the mechanism are operatively connected directly or indirectly to a support frame which includes first and second mounting plate sections  58  and  59 . As best seen in  FIGS. 5 to 7  mounting plate section  59  comprises two parts. The mechanism includes an input transmission assembly  70  which includes an input shaft  71  and a bevel gear  72  which is operatively connected to the control meter  20  through calibrating gear box  22 . The interconnection between the control meter  20  and input assembly  70  is best seen in  FIGS. 2(   a ) and  2 ( b ). The control meter  20  is connected to the calibrating gear box  22  having an output shaft  32  to which a bevel gear  34  is mounted. Bevel gear  34  is in engagement with bevel gear  72  of the input transmission assembly  70 . The input transmission assembly  70  further includes an input gear  73  which is operatively connected to a first gear train. The display wheels  53 ,  55 ,  57  are carried on a support shaft  74  which extends between mounting plate sections  58  and  59 . 
   The first setting wheel  52  is operatively connected to display wheel  53  via the first gear train which will be described in more detail below. In the disengaged position it is disconnected from the gear train. To this end the setting wheel  52  is mounted to a spring biased pivot member  60  and arranged such that depression of the wheel  52  causes pivotal movement of the pivot member  60  so that the setting wheel will adopt the engaged position wherein it is in operative connection with the display wheel  53  via the first gear train. This is best seen in  FIGS. 3(   b ),  5  and  7 . The pivot member  60  includes a mounting leg  61  to which the first setting wheel is rotatably mounted and a spring leg  62  which in the assembled position abuts against a stop  63 . ( FIG. 3(   b )). Manual depression of the first setting wheel  52  causes partial rotation of pivot member  60  against the action of spring leg  62  so that the wheel  52  engages the first gear train. 
   The first gear train includes a thumb gear  84  which is operatively connected to the setting wheel  52  for rotation therewith and is connectable with an idler drive gear  85  operable to drive an idler gear  86  which in turn engages a gear section  79  of a display wheel  53 . The drive gear  85  and idler gear  86  are mounted on an idler gear shaft  87 . The idler gear shaft  87  is mounted at a pivot mounting  88  on plate  58  for limited pivotal movement for reasons which will become hereinafter apparent. The other end of the shaft  87  is received within slots  51 ,  76  and  77  in frame  59  and pivot member  60 . 
   The idler drive gear section  89  is in meshing engagement with input gear  73 . When setting wheel  52  is depressed, thumb gear  84  moves into meshing engagement with idler drive gear  85  and depression into its extreme position causes disengagement of input gear  73  from idler drive gear section  89 . When depressed, rotation of setting wheel  52  will cause rotation of display wheel  53  so that it can be set at a selected unit of volume. 
   The second setting wheel  54  is operatively connected to display wheel  55  via a second gear train. The second setting wheel  54  is mounted to a pivot member  160  which is mounted to mounting plate  59  and operates in a similar fashion to the pivot member  60  so that the setting wheel can be disengaged from the second gear train. 
   The second gear train includes a thumb gear  184  which is directly connected to the setting wheel  54 . The gear train further includes an idler drive gear and idler gear which engages a gear section  179  on display wheel  55 . The structure of the second gear train is substantially the same as that of the first gear train. The second setting wheel  54  and its associated gear train do not engage directly with the input transmission assembly  70  at any time. 
   The arrangement of the third setting wheel  56  is similar to those described above and is best seen in  FIG. 4 . Again there is an operative connection between the third setting wheel  56  and third display wheel  57  via a third gear train. The third setting wheel  56  is mounted to a pivot member  260  mounted to plate  58 . 
   The structure and operation of pivot member  260  is the same as the pivot members  60  and  160  described earlier. The third gear train includes a thumb gear  284  which is directly connected to the setting wheel  57 . The third gear train further includes an idler drive gear  285  and an idler gear  286 . The display wheel has a gear section  297  wheel is in meshing engagement with idler gear  286 . The third gear train does not directly engage with the input transmission assembly  70  at any stage. 
   A first indexing arrangement is provided between the first and second display wheels  53  and  55  and a second indexing arrangement is provided between the second and third display wheels  55  and  57  in order to provide for correct timing between the two associated display wheels. The first indexing arrangement includes an indexing element  90  in the form of two gear teeth  91  adapted to be engaged by the drive gear  185  of the second gear train. The second indexing arrangement includes an indexing element comprising two gear teeth on the second display wheel. Each arrangement further incudes a locating device comprising a detent cam  93  and  97  which cooperate with a follower  94  and  98  on spring arm  92  and  99  ensure that the display wheels are correctly indexed with respect to one another. 
   The setting mechanism enables a preselected volume of fluid required to be dispensed to be displayed on the display wheels. When the trigger  17  of the device is activated to open valve  18  the volume of fluid passing through the device drives the valve control meter which in turn drives the calibrating gear which in turn drives the input transmission assembly  70  causing the display wheels to rotate in volume display descending fashion. The display wheel  52  is directly connected to transmission assembly  70 . Each revolution of the display wheel  52  will cause engagement between that wheel and wheel  54  through the indexing mechanism associated therewith causing rotation thereof each time the indexing mechanism engages. The wheel  54  and wheel  56  will operate in a similar manner to that of wheel  52  and  54  until a reading is reached whereby the latching mechanism is triggered. 
   The Latch Mechanism 
   The latch mechanism includes a latch setting assembly  300  associated with trigger  17  of the dispensing device which is operable to set the latch mechanism when the trigger  17  is depressed and in the second position. The latch setting assembly  300  includes a setting button  302  mounted on the trigger  17 , and a connector arm  303  operatively connected to the button  302 . 
   The latch mechanism further includes a first catch assembly comprising a control member  305  which is pivotally mounted to a part of the body portion  26  of the trigger  17 . The control member  305  includes a catch  315  and push element  316  adapted to cooperate with a latch member  307 . A spring (not shown) urges the control member  305  into the position shown in  FIG. 19 . The latch member  307  is in the form of a latch plate pivotally mounted to the housing at pivot mounting  319 . The latch member  307  includes first and second latching sections  317  and  318  defined by shoulders formed as edges of apertures in the latch plate. 
   The latch mechanism may further include a second catch assembly comprising a catch member  308  having a catch  314  thereon is operatively connected to a trip assembly  312 . A spring  319  acts on catch member  308  as shown. 
   The trip assembly  312  includes a trip pin  322  actuatable by a boss  324  on the display wheel  57 . A coupling member  326  is caused to be moved by the trip pin  322  whereupon it is engaged by activating projection  330  on display wheel  55 . 
   The latching mechanism is operable so as to be able to adopt a latched position in which position the valve  18  of the dispensing device is open and a release position in which the valve  18  can return to a closed position. Preferably the trigger  17  can be activated to cause the valve to open whether or not the latch mechanism is in the latched position. 
   To set the latching mechanism the trigger  17  is depressed. This causes rotation of the shaft  27  and cam surface  28  which acts on the valve follower  19  to cause the valve  18  to open. The rotational movement of the trigger body  27  moves the control member  305  into engagement with the latch plate  307 . The latch plate  307  is pivotal about its pivot mounting  319  causing the catch  314  to engage with first latching section  317  on latch plate  307 . At this stage the catch  315  is not engaged with latching section  318  and the trigger  17  can return to its first position under the influence of the spring (not shown) described earlier. 
   To set the trigger  17  it is moved to its second position causing a pivotal movement of the control member  308  and depression of the button  302  causes arm  303  to engage the end of the control member  308  so that the catch  315  engages latching section  318  thereby holding the trigger in the second position. 
   In the embodiment shown, the setting mechanism enables a volume to be set correlating to three display wheels. For example, the device can be set to read tenth increments, unit increments and decade increments. The selected volume is set by pressing and rotating to the selected reading each of the thumb wheels each of which is associated with a respective display wheel. When moved the thumb wheels disengage from the other wheels so that they can be separately set without interference from the other wheels. All wheels can be rotation in both directions. 
   When the trigger is moved to the second position and the latch mechanism set fluid can flow through the meter and the display wheels will rotate counting down towards zero. When the meter reaches zero the valve latch is released and the flow stops. 
   Finally, it is to be understood that various alterations, modifications and/or additions may be incorporated into the various constructions and arrangements of parts without departing from the spirit or ambit of the invention.