Patent Publication Number: US-2005121472-A1

Title: Valve unit

Description:
FIELD OF INVENTION  
      The present invention relates to a valve unit.  
      More particularly, the present invention relates to a valve unit for dispensing flowable materials.  
     BACKGROUND TO INVENTION  
      It is often desirable to obtain a fixed volume of substance out of a tube or bottle. When working with liquids, a fixed volume can be relatively easily measured off in a syringe or a measuring cup. As an aid in dispensing fixed volumes and in order to reduce the likelihood of spillage, a number of measuring caps have been developed for attachment on a bottle or tube.  
      One such measuring dispensing cap is shown in U.S. Pat. No. 6,041,979. This cap has a housing for attachment to a container and a spout rotatable relative to the housing. A transfer compartment is defined in the spout for firstly receiving material from the container and thereafter dispensing the material after the container is sealed. However, this dispensing cap and other measuring devices cannot be easily used with pastes, creams, salves or other high viscosity substances, which are not readily flowable, as the devices do not allow pressure to be exerted on the material while in the transfer chamber. Without such pressure application, the paste will not flow out of the transfer chamber.  
      Another metered liquid squeeze container is shown in U.S. Pat. No. 6,186,367. Although this dispenser allows pressure to be applied to the material within the dispensing chamber, i.e. by squeezing the container, the dispenser still is only able to function with a material of relatively low viscosity. If a high viscosity material is used, the material will not flow back into the container and the measuring function of the cap will not function.  
      It is an object of the invention to suggest a valve unit, which will assist in overcoming these problems.  
     SUMMARY OF INVENTION  
      According to the invention, a valve unit includes a body; a movable member movably associated with the body; a first passage extending through the body; a second passage extending through the movable member, the movable member being adapted to align the second passage with the first passage; and a control member movably located inside the second passage, the control member being adapted to regulate the filling of and the exhausting of a flowable substance from the second passage through the first passage.  
      The movable member may be located in a recess in the body.  
      The recess may be a bore.  
      The recess may be located centrally within the body.  
      The body may be cylindrical.  
      The first passage may extend through the body traversing the recess along its diameter.  
      The movable member may be a spigot rotatably located in the recess.  
      The movable member may be provided with a gripping member extending beyond the body for rotation of the movable member.  
      The movable member may be cylindrical having a diameter substantially similar to the diameter of the recess.  
      The second passage may extend through the movable member having openings on opposite sides of a diameter of the movable member.  
      The second passage may have a slightly larger diameter than the first passage.  
      The control member may be adapted to block off the first passage when moved into contact with the body.  
      The control member may be a spherical ball.  
      The control member may have a diameter substantially similar to a diameter of the second passage.  
      The control member may have a diameter larger than a diameter of the first passage.  
      The valve unit may include attachment means for attaching the body to a supply of a flowable substance, such as a tube of paste.  
      The attachment means may be a screw-on or clip-on connection.  
      The valve unit may include alignment means adapted to align the first and second passages so that they are continuous with each other.  
      The alignment means may include a groove provided in the body and being adapted to accept a pin extending from the movable member, or vice versa.  
      The groove may describe a substantially arcuate path parallel to a diameter of the bore.  
      The groove may extend though substantially 180°.  
      The alignment means may include a ratchet formation allowing unidirectional rotation of the movable member.  
      The valve unit may include a cap adapted to be removably attached to the body.  
      The cap may have a lip adapted to prevent attachment of the cap if the first and second passages are in alignment.  
      The cap may have a lip adapted to prevent movement of the movable member when the cap is attached to the body.  
      The valve unit may include a one-way valve associated with the first passage being adapted to reduce retraction of the flowable substance into a container during use.  
      The second passage may have flexible side walls.  
      The second passage may be adapted to be partially closed by a blocking member to restrict movement of the control member.  
      The movable member may include a bypass passage in which no control member is provided and being adapted to allow unrestricted and unmeasured volume of the flowable substance to pass through the first passage.  
      The valve unit may include a self-closing mechanism being adapted to cause the first and second passages to be unaligned when not in use.  
      The self-closing mechanism may be a spring loaded cam.  
      The valve unit may include a counter for indicating a total number of dosages dispensed through the first passage.  
      Also according to the invention, a valve unit includes a dispenser having a dispenser inlet and a dispenser outlet; a metering chamber, having a predetermined volume and two chamber openings, being movably located inside the dispenser in a manner allowing at least one of the chamber openings to be moved between a first position where it is in alignment with the dispenser inlet and a second position where it is alignment with the dispenser outlet; and a control member movably located inside the metering chamber between the chamber openings and being adapted to selectively close off the dispenser outlet.  
      Further according to the invention, a method of dispensing a flowable substance includes the steps of expressing a first volume of the substance into a metering chamber; and of exhausting the first volume of substance from the metering chamber while simultaneously expressing a further volume of the substance into the metering chamber.  
      A control member may be movably located in the metering chamber for separating the first volume from the further volume of substance.  
      The further volume of substance may forcibly act against the control member to move it within the metering chamber and thereby causing the control member to exhaust the first volume of substance out of the metering chamber.  
      The valve unit may be used in a number of various applications, for example such as for industrial filling lines for filling tubes or bottles, for measuring and mixing various fluids, for infusion pumps, for attachment to syringes to deliver fixed doses of medication, for drop dispensing, for substituting rotary valves found in mass spectrometers, or for measuring two-part Epoxy adhesives. 
    
    
     BRIEF DESCRIPTION OF DRAWINGS  
      The invention will now be described by way of example with reference to the accompanying schematic drawings.  
      In the drawings there is shown in:  
       FIG. 1 a  perspective view of a first embodiment of a valve unit in accordance with the invention;  
       FIG. 2  an exploded perspective view of the valve unit shown in  FIG. 1 ;  
       FIG. 3 a  side view of a body of the valve unit seen along arrow III in  FIG. 2 ;  
       FIG. 4 a  plan view of the body of the valve unit seen along arrow IV in  FIG. 3 ;  
       FIG. 5 a  side view of a spigot of the valve unit seen along arrow V in  FIG. 2 ;  
       FIG. 6 a  bottom view of the spigot seen along arrow VI in  FIG. 5 ;  
       FIG. 7 a  plan view of the valve unit shown in  FIG. 1 , shown joined to a supply of a substance;  
       FIG. 8 a  plan view of the valve unit shown in  FIG. 7 , shown charged or filled with substance;  
       FIG. 9 a  plan view of the valve unit shown in  FIG. 7 , shown ready to discharge the substance;  
       FIG. 10 a  plan view of the valve unit shown in  FIG. 7 , shown after discharging the substance;  
       FIG. 11  an exploded perspective view of a second embodiment of a valve  20  unit in accordance with the invention;  
       FIG. 12  an assembled sectional side view of the valve unit shown in  FIG. 11 ;  
       FIG. 13  an enlarged detail of the area indicated by arrow XIII in  FIG. 12 ;  
       FIG. 14  an assembled view of the valve unit shown in  FIG. 13  provided with a one-way valve;  
       FIG. 15  on an enlarged scale, a sectional view of a third embodiment of a valve unit in accordance with the invention showing a variable dosage passage;  
       FIG. 16 a  side view of a fourth embodiment of a valve unit in accordance with the invention;  
       FIG. 17 a  sectional plan view seen along arrows XVII-XVII in  FIG. 16 ; and  
       FIG. 18 a  sectional side view seen along arrows XVIII-XVIII in  FIG. 16 . 
    
    
     DETAILED DESCRIPTION OF DRAWINGS  
      Referring to  FIGS. 1 and 2 , a first embodiment of a valve unit in accordance with the invention, generally indicated by reference numeral  20 , is shown. The valve unit  20  includes a body  22 , a spigot  24  movably joined to the body  22 , and a control member in the form of a ball  26  movably associated with the spigot  24 .  
      As shown in  FIGS. 3 and 4 , the body  22  is cylindrical in shape and defines a centrally located cylindrical bore  28 . A first passage  30 , having an inlet  32  and an outlet  34 , extends through the body  22  traversing the bore  28  along a diameter of the bore  28 . An internal screw thread  36  is provided in the passage  30  extending from the inlet  32  for joining the valve unit  20  to a supply source during use. The body  22  further is provided with an arcuate guide groove  38 , which extends through substantially 180°.  
      Referring now to  FIGS. 5 and 6 , the spigot  24  has a diameter substantially similar to the diameter of the bore  28  and is rotatably located therein. The spigot  24  has an outward flange  40  at its end protruding from the bore  28 . A second passage  42  extends through the spigot  24 , the second passage  42  having openings on opposite sides of a diameter of the spigot  24 . This allows the second passage  42  to be aligned with the first passage  30 . The diameter of the second passage  42  is slightly larger than the diameter of the first passage  30 . A pin  44  extends from the flange  40  into the groove  38 .  
      The control member  26  is a spherical ball having a diameter substantially similar to a diameter of the second passage  42  and larger than a diameter of the first passage  30 .  
      Referring now to FIGS.  7  to  10 , in use, the valve unit  20  is joined to supply source, such as a tube  46  of paste. The spigot  24  is rotated so that the first and second passages  30 , 42  are in alignment, i.e. when the pin  44  is at one end of the groove  38  (as shown in  FIG. 7 ). By pressing the tube  46 , a first volume of paste  48  is expressed into the second passage  42  of the valve unit  20  (as shown in  FIG. 8 ). Once the second passage  42  is filled with the paste  48 , the ball  26  abuts against the body  22  near the outlet  34 . This closes off the first passage  30  and prevents further paste  48  from being expressed from the tube  46 .  
      As shown in  FIG. 9 , the spigot  24  is rotated relative to the body  22  in the direction of arrow  50  until the first and second passages  30 , 42  are again aligned, i.e. with the pin  44  being located at an opposite end of the groove  38 . The ball  26  thus abuts against the body  22  near to the inlet  32  of the first passage  30 .  
      Finally, the first volume of paste  48  is exhausted from the valve unit  20  by expressing a further volume of paste  52  into the valve unit  20 . As the second volume of paste  52  enters the second passage  42 , it moves the ball  26  until it again abuts against the body  22  near the outlet  34 . Simultaneously, the ball  26  acts to exhaust the first volume of paste  48  from the second passage  42 .  
      Additional volumes of paste can be obtained by repeating the above steps as often as required.  
      The volume of paste remaining in the first passage  30  can be reduced by shortening its length, e.g. by cutting away a part of the body  22 .  
      Referring now to FIGS.  11  to  13 , a second embodiment of a valve unit in accordance with the invention, generally indicated by reference numeral  54 , is shown. The valve unit  54  includes a first body member  56  connectable to a second body member  58 , which second body member  58  is adapted to be joined to a tube  60  of paste. A spigot  62  is movably located within the first body member  56 , and a control member in the form of a ball  64  is movably associated with the spigot  62 .  
      The first body member  56  is cylindrical in shape and defines a centrally located  1 . 5  cylindrical bore  66 . A first passage  68 , having an inlet  70  and an outlet  72 , extends through the first body member  56  traversing the bore  66  along its diameter. The first body member  56  and the second body member  58  are attachable by clip engagement of a groove  74  and an annular ridge  76  respectively provided on the two member  56 , 58 .  
      The second body member  58  has an internal screw thread  78  for attachment to the tube  60  during use.  
      The spigot  62  is cylindrical in shape having an external diameter which is substantially similar to the diameter of the bore  66 , with the spigot  62  being rotatably located within the bore  66 . The spigot  62  has two oppositely located outward flanges  80 , 82  along its outer circular edges for locating the spigot  62  within the bore  66 . A second passage  84 , which has a diameter slightly larger than the diameter of the first passage  68 , extends through the spigot  62 , the second passage  84  having openings on opposite sides of a diameter of the spigot  62 . Thus, when the spigot  62  is located in the bore  66 , the second passage  84  can be aligned with the first passage  68  by suitably rotating the spigot  62 . Sealing rings, such as O-rings (not shown), are provided adjacent the flanges  80 , 82  and around the openings of the second passage  84  to reduce leakage during use.  
      A protruding gripping member  86  extends from the spigot  62  to enable easy rotation of the spigot  66  inside the bore  66 .  
      A tongue  88  extends from the second body member  58  through a slot  90  in the first body member  56  and contacts against the spigot  62 . The flange  80  of the spigot  62  has a number of spaced apart cut-outs  92 , which cooperate with the tongue  88  to form a ratchet allowing unidirectional rotation of the spigot  62 . The ratchet interaction between the cut-outs  92  and the tongue  88 , which is more clearly shown in  FIGS. 12 and 13 , also assist in aligning the first and second passages  68 , 84  during use.  
      The control member  64  is a spherical ball having a diameter substantially similar to a diameter of the second passage  84  and larger than a diameter of the first passage  68 .  
      A cap  94  is adapted to be removably placed over the valve unit  54 . The cap  94  has a lip  96  which allows the cap  94  to be attached to the valve unit  54  only once the spigot  62  has been turned so that the first and second passages  68 , 84  are transversely positioned relative to each other, i.e. closing the valve unit. The lip  96  also prevents rotation of the spigot  62  while the cap  94  is attached.  
      In use, the valve unit  54  is joined to the tube  60  of paste. After removal of the cap  94 , the spigot  62  is rotated so that the first and second passages  68 , 84  are in alignment and the tongue  88  engages into a cut-out  92 . By pressing the tube  60 , a first volume of paste is expressed into the second passage  84 , similar to  FIG. 8 . Once the second passage  84  is filled with the paste, the ball  64  abuts against the first body member  56  near the outlet  72 . This closes off the first passage  68  and prevents further paste from being expressed from the tube  60 .  
      The spigot  62  is then rotated through 180° (two ratchets) until the first and second passages  68 , 84  are again aligned. The ball  64  thus abuts against the first body member  56  near to the inlet  70  of the first passage  68 .  
      Finally, the first volume of paste is exhausted from the valve unit  54  by simultaneously expressing a further volume of paste into the second passage  84 , similar to  FIG. 10 . As the second volume of paste enters the second passage  84 , it moves the ball  64  until it again abuts against the body  56  near the outlet  72 . The ball  64  thus acts to exhaust the first volume of paste from the second passage  68 .  
      Additional volumes of paste can be obtained by repeating the above steps as often as required.  
      As shown in  FIG. 14 , the valve unit  54  can be provided with a one-way valve  98 . Although the one-way valve  98  is shown at the outlet  72  of the first passage  68 , it can also be equally effectively be located at the inlet  70 . The one-way valve  98  prevents the paste, or possibly air, from being retracted into the tube  60  when pressure is released therefrom, e.g. when a partial vacuum is created inside the tube  60  by the resiliency of the tube  60  returning to its original shape.  
      Referring no to  FIG. 15 , a the valve unit  54  can include a spigot  62  provided with a second passage  100  having flexible side walls  102 . Thus by providing a blocking member  104 , which partially restricts the second passage  100  and past which the control member  64  is not able to move, the effective volume of the second passage  100  can be altered. By providing discrete positions in which the blocking member  104  can be located, various fixed volumes of the second passage  100  can be obtained, i.e. 1 ml, 5 ml, 10 ml or 15 ml as shown in  FIG. 15 .  
      As shown in FIGS.  16  to  18 , a fourth embodiment of a valve unit in accordance with the invention, generally indicated by reference numeral  106 , is shown. The valve unit  106  includes a spigot  108  provided with two passages  110 , 112 . The passage  110  is substantially similar to the second passage  84 , shown in FIGS.  11  to  14 , which includes a control member  64 . However, the passage  112  is a type of purge passage, in which no control member  64  is provided, thus allowing unrestricted amounts of paste to pass through the valve unit  106 .  
      Also shown in  FIG. 16  is a stopper  114 , which is integrally formed with the spigot  108 . The stopper  114  is adapted to abut against one of two stop faces  116 . 1 , 116 . 2  provided in the body  118  and assists in aligning the respective first and second passages.  
      It is envisioned that the first and second body members  56 , 58  can be integrally formed with each other in a single body member.  
      The valve unit  20  can be manufactured by injection moulding from plastics material.  
      The control member  26 , 64  can have any shape suitable for closing off the outlet  34 , 72 . The control members  26 , 64  can be solid or hollow and can be made of plastics material, such as polystyrene.  
      The valve unit  20 , 54 , 106  can be self-closing wherein the spigot  24 , 62 , 108  automatically rotates so that the first passages  30 , 68  are unaligned with the second passages  42 , 84 , 100 , 110 , 112  when the valve unit is not in use. This self-closing feature can include a spring loaded mechanism or a cam mechanism.  
      The valve unit  20 , 54 , 106  can include a counter for indicating the total number of dosages dispensed form the tube  46 , 60 .  
      In each of the embodiments described above, it should be noted that the second passages  42 , 84 , 100 , 110 , 112  need not be straight but can have any other suitable shape for defining an area within the spigot  24 , 62 , 108 .