Abstract:
A dispensing device including a pump assembly for pumping out the viscous liquid material stored in the device. The pump has a cylinder and a piston disposed within the cylinder, wherein the cylinder includes a cylinder inlet valve and the piston includes a cylinder outlet valve. Each operation of the pump assembly causes the piston to move in a first direction toward the cylinder inlet valve and in a second direction away from the cylinder inlet valve. The movement of the piston in the first direction causes the cylinder inlet valve to close and the cylinder outlet valve to open. The movement of the piston in the second direction causes the cylinder inlet valve to open and the cylinder outlet valve to close. When the pump assembly is primed with viscous liquid material, movement of the piston in the first direction pumps a predetermined volume of the viscous liquid material from the cylinder through the opened cylinder outlet valve, thereby causing a substantially corresponding predetermined volume of the viscous liquid material to be dispensed by the device. Movement of the piston in the second direction draws a substantially corresponding predetermined volume of the viscous liquid material from the device into the cylinder through the opened inlet valve thereby refilling the cylinder with the viscous material.

Description:
FIELD OF THE INVENTION 
     This invention relates to manually operated dispenser devices, and in particular, to a manually operated dispenser device for metering doses of viscous materials such as nail polish, lipstick, foundation, makeup and the like. 
     BACKGROUND OF THE INVENTION 
     There are many known dispenser devices for dispensing viscous material. Such devices have been employed in a variety of applications for discharging many different types of viscous materials. A common application for dispensers of this kind is in the field of cosmetic applicators. Typical cosmetic applicators are pen-like in design and dispense a cosmetic fluid onto an integrally disposed applicator when actuated by the user. 
     Pen-like fluid dispensing devices for manual user operation, especially those devices used for dispensing cosmetic fluids, must be capable of being fabricated inexpensively from readily available materials. In addition to the importance of minimizing manufacturing costs, it is equally important that such devices be fabricated to close tolerances in order to ensure proper fit and cooperative inter-engagement between both fixed and relatively movable parts, and to provide for reliable operation of the dispenser throughout its intended useful life which is usually until the initial supply of stored fluid is exhausted. In the case of cosmetic fluid dispensers, assuring continued operative reliability is much more difficult. This is because cosmetic fluids such as nail enamels, are relatively caustic to many common construction materials and quickly thicken and harden in the absence of adequate fluid tight seals, makes continued operative reliability much more difficult. 
     Typical known and commercially available dispenser devices commonly employ relatively complex mechanical designs which use large numbers of mutually engaging parts that must all cooperatively interact in order for the device to operate. Dispenser devices of this type are usually difficult and expensive to manufacture and often exhibit high failure rates as the devices approach the end or latter portion of their intended, useful lives. Moreover, many of these devices are difficult to operate. 
     Accordingly, there is a need for a dispenser device for dispensing metered doses of viscous material with enhanced reliability and ease of operation. 
     SUMMARY OF THE INVENTION 
     A dispensing device comprising a pump assembly for pumping out the viscous liquid material stored in the device. The pump includes a cylinder and a piston disposed within the cylinder, wherein the cylinder has a cylinder inlet valve and the piston has a cylinder outlet valve. Each operation of the pump assembly causes the piston to move in a first direction toward the cylinder inlet valve and in a second direction away from the cylinder inlet valve. The movement of the piston in the first direction causes the cylinder inlet valve to close and the cylinder outlet valve to open. The movement of the piston in the second direction causes the cylinder inlet valve to open and the cylinder outlet valve to close. When the pump assembly is primed with viscous liquid material, movement of the piston in the first direction pumps a predetermined volume of the viscous liquid material from the cylinder through the opened cylinder outlet valve, thereby causing a substantially corresponding predetermined volume of the viscous liquid material to be dispensed by the device. Movement of the piston in the second direction draws a substantially corresponding predetermined volume of the viscous liquid material from the device into the cylinder through the opened inlet valve thereby refilling the cylinder with the viscous material. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The advantages, nature and various additional features of the invention will appear more fully upon consideration of the illustrative embodiments now to be described in detail in connection with accompanying drawings wherein: 
     FIG. 1 is a sectional view of a device for dispensing metered doses of viscous material according to an embodiment of the invention; 
     FIG. 2A is a sectional view of the pump assembly of the device of FIG. 1; 
     FIG. 2B is a detailed sectional view the pump housing of the pump assembly; 
     FIG. 3 is a detailed sectional view of the cylinder of the dispensing pump; 
     FIGS. 4A and 4B are detailed elevational views of the needle sealing element of the dispensing pump; 
     FIGS. 5A and 5B are detailed elevational views of the diaphragm member of the dispensing pump; 
     FIGS. 6A and 6B are detailed elevational views of the biasing element of the dispensing pump; 
     FIG. 7A is a detailed sectional view of the pump piston of the dispensing pump; 
     FIGS. 7B and 7C are detailed elevational views of the pump piston of the dispensing pump; 
     FIGS. 8A and 8B are detailed elevational views of the button of the dispensing pump; 
     FIG. 9A is a detailed sectional view of the applicator holder of the applicator assembly; 
     FIG. 9B is a detailed elevational view of the applicator holder of the applicator assembly; 
     FIGS. 10A and 10B are detailed elevational views of the applicator member of the applicator assembly; 
     FIG. 10C is a detailed sectional view of the applicator member of the applicator assembly; 
     FIGS. 11,  11 B, and  11 C are detailed sectional views of the transfer tube of the applicator assembly; 
     FIG. 12A is a detailed sectional view of the passive piston of the reservoir assembly; 
     FIG. 12B is a detailed elevational view of the passive piston of the reservoir assembly; and 
     FIGS. 13A and 13B are sectional views of the device depicting its operation. 
    
    
     It should be understood that these drawings are for purposes of illustrating the concepts of the invention and are not to scale. 
     DETAILED DESCRIPTION OF THE INVENTION 
     FIG. 1 shows a sectional view of a device  10  for dispensing metered doses of viscous material according to an embodiment of the invention. The device  10  generally comprises an applicator assembly  16  disposed at a forward end  12  thereof, a reservoir assembly  18  disposed at a rearward end thereof  14 , and a pump assembly  20  disposed between the applicator assembly  16  and the reservoir assembly  18 . The device  10  is typically pen-like in design, however, other embodiments of the device can be configured to be shorter and wider if desired. 
     FIG. 2A shows a sectional view of the pump assembly  20  of the device  10 . The pump assembly  20  includes an opened ended, elongated cylindrical pump housing  21  which contains a dispensing pump  22 . As shown in the sectional view of FIG. 2B, the pump housing  21  has an axial bore  23  and a side wall aperture  24  that opens into the bore  23 . A button hinge flange  61  is provided just below the forward end of the pump housing aperture  24 . The forward end of the pump housing  21  is conventionally adapted for retaining the applicator assembly  16  therein and the rearward end of the pump housing  21  includes an internal screw thread  25  for threadedly connecting the reservoir assembly  18 . The inner surface of the pump housing  21  includes an annular locating groove  26  and a flange  40  both formed adjacent the forward end of the thread  25 . 
     Referring again to FIG. 2A, the dispensing pump  22  generally comprises a cylinder  27 , a needle sealing element  28  mounted in the cylinder  27 , a pump piston  29  reciprocally disposed in the cylinder  27 , a biasing element  30  positioned in the cylinder  27  between the pump piston  29  and the needle sealing element  28 , a flexible circular diaphragm member  46  disposed between the sealing element  28  and the cylinder  27  and a button  31  for finger operation of the pump  22 . 
     FIG. 3 shows a detailed sectional view of the cylinder  27  of the dispensing pump  22 . The cylinder  27  has an open forward end  32  and a closed rearward end  33 . The inner surface  34  of the cylinder  27  at its forward end  32  tapers outwardly to allow insertion of the pump piston  29  during assembly of the pump  22 . The closed rearward end  33  of the cylinder  27  includes a centrally located inlet orifice  39 . The inner surface  34  of the cylinder  27  adjacent the closed end  33  thereof includes an annular seating flange  35  for mounting the needle sealing element  28 . The outer surface  36  of the cylinder  27  adjacent the forward open end  32  thereof, has an annular locking bead  37  and a flange  38  which together coact with the pump housing&#39;s interior locating groove  26  and flange  40  arrangement to mount the cylinder  27  within the axial bore  23  of the pump housing  21 . When mounted, the rearward end  33  of the cylinder  27  extends beyond the rearward end of the pump housing  21  into the reservoir assembly  18  as shown in FIG.  1 . 
     FIGS. 4A and 4B show detailed elevational views of the needle sealing element of the dispensing pump  22 . The needle sealing element  28  includes a base  41  with a plurality of radially extending spokes  42  disposed at the rearward end of the base  41  and a shaft  43  extending from the forward end of the base  41 . The spokes  42  of the needle sealing element  28  rest on the seating flange  35  of the cylinder  27  when the element  28  and the cylinder  27  are assembled. The rearward end of the base  41  further includes a centrally located aperture  45 . The forward end of the shaft  43  includes an enlarged, forwardly tapered sealing member  44 . 
     FIGS. 5A and 5B show detailed elevational views of the diaphragm member  46  of the dispensing pump  22 . The diaphragm member  46  includes a unitarily formed centrally located mounting post  47  which is slidably received in the aperture  45  of the needle sealing element base  41 . The mounting post  47  aligns the diaphragm member  46  with the cylinder inlet orifice  39  thus, forming a cylinder inlet valve  48  (FIG. 2A) as will be explained further on. 
     The pump piston  29  of the dispensing pump  22  is shown in detail in the sectional view of FIG.  7 A and the elevational views of FIGS. 7B and 7C. The pump piston  29  comprises an elongated tubular member having an outer surface  107 , an inner surface  49 , an open forward end  50  and an outwardly flared rearward end  51 . The inner surface  49  of the pump piston  29  adjacent the rearward end  51  thereof is occluded by a partition member  52 . The partition member  52  includes an outlet orifice  53  with an annular beveled sealing surface  54  on its forward side and an annular recess  57  on its rearward side. The outer surface  107  of the pump piston  29  includes a pair of cam surfaces  55  which are formed on opposite sides thereof. The cam surfaces  55  are disposed at an angle θ measured from the longitudinal axis A of the pump piston  29 , this angle θ typically measuring between about 40 and 50 degrees. The cam surfaces  55  coact with the button  31  positioned within the aperture  24  of the pump housing  21  as will be explained further on in greater detail. The cam surfaces  55  are connected by an arcuate support member  106  that engages the inner surface of the pump housing  21  (FIG. 2A) to prevent bending of the pump piston  29  when actuated by the button  31 . 
     As shown in FIG. 2A, the rearward end  51  of the piston  29  fits into the open end  32  of the cylinder  27 , such that the rearward end  51  of the piston  29  sealingly engages the inner surface of the cylinder  27 . Further, the sealing member  44  of the needle sealing element  28  extends through the outlet orifice  53  of the piston  29  thereby defining a cylinder outlet valve  56 . 
     FIGS. 6A and 6B show detailed elevational views of the biasing element  30  of the dispensing pump  22 . The biasing element  30  typically comprises a conventional hectically wound coil metal or plastic spring. As shown in FIG. 2A, the biasing element  30  is disposed in the cylinder  27  such that the forward end of the spring is seated in the recess  57  defined in the partition member  52  of the pump piston  29  and the rearward end of the spring is seated on the spokes  42  of the needle sealing element  28 . Thus, in a non-dispensing mode (FIG.  1 ), the biasing element  30  biases the beveled sealing surface  54  of the pump piston outlet orifice  53  against the sealing member  44  of the needle sealing element  28  thereby closing the cylinder outlet valve  56  (FIG.  2 A). 
     FIGS. 8A and 8B show detailed elevational views of the button  31  of the dispensing pump  22 . The button  31  has a upside-down U-shaped cross-section formed by a generally convex top wall  58  and a pair of parallel spaced side walls  59 . Slots  60  are formed in the forward edges of the side walls  59 . The slots  60  permit the button  31  to pivot on the hinge flange  61  of the pump housing aperture  24  while the rearward corners  62  of the button side walls  59  slidingly engage the cam surfaces  55  of the pump piston  29 . A pair of elongated projections  63  are provided on the outer surface of each button side wall  59 . The projections  63  engage the inner surface of the pump housing  21  to prevent the button  31  from being separated from the pump housing  21 . 
     Referring again to FIG. 1, the applicator assembly  16  includes an applicator holder  64 , an applicator member  65  disposed in the holder  64 , a transfer tube  66  inserted in the applicator member  65 , a second flexible circular diaphragm member  89  disposed between the transfer tube  66  and applicator member  65  and a removable closure  67  for sealingly covering the applicator member  68 . 
     The applicator holder  64  of the applicator assembly  16  is shown in detail in the sectional view of FIG.  9 A and the elevational view of  9 B. The applicator holder  64  has a generally cylindrical an outer surface  69  and a stepped cylindrical inner surface  70 . The outer surface  69  tapers at  72  toward the inner surface  70  at the forward end  71  of the holder  64 . An annular bead  73  for snap-engaging the closure  67  to the applicator assembly  16 , is provided on the outer surface  69  adjacent the tapered outer sealing surface  72 . The outer surface  69  includes two annular barb projections  75  at the rearward end  74  of the holder, for fixing the applicator assembly  16  in the forward end of the pump housing axial bore  23 . A circumferential flange  76  on the outer surface  69  of the holder  64  abuts against the edge of the pump housing  21  to prevent the holder  64  from being pushed into the housing  21  during use. 
     The applicator member  65  of the applicator assembly  16  is shown in detail in the elevational views of FIGS. 10A and 10B, and the sectional view of FIG.  10 C. The applicator member  65  has a generally cylindrical stepped outer surface  77 . The outer surface  77  defines a pair of converging beveled surfaces  78  at the forward end  79  of the member  65  which function as dispensing contact surfaces. The applicator member  65  includes an interior bore  80  that extends forwardly from the rearward end  81  thereof to an annular channel  82  which then branches off into a pair of smaller, concentrically arranged inner and outer annular channels  84 ,  85  that communicate with the beveled surfaces  78 . In other embodiments of the device, the applicator member can be conventionally configured as a brush, a ball carrying member, one or more dispensing ports and the like. 
     The details of the transfer tube  66  of the applicator assembly  16  are shown in the sectional views of FIGS. 11A,  11 B, and  11 C. The transfer tube  66  has a forward open end  86  and a rearward open end  87 . Four equally-spaced lugs  88  are formed on the interior at the forward end  86  of the tube  66 . The lugs  88  secure the second diaphragm member  89  (shown in detail in FIG. 11B) to the transfer tube  66  by the member&#39;s  89  mounting post  90 . 
     As shown in FIG. 1, the forward open end  86  of the transfer tube  66  is fixedly disposed in the bore  80  at the rearward end of the applicator member  65  and the rearward open end  87  extends into the forward open end  50  of the pump piston  29 . The second flexible circular diaphragm member  89  selectively opens and closes the forward open end  86  of the transfer tube  66  as will be explained further on. 
     Referring still to FIG. 1, the removable closure  67  of the applicator assembly  16  includes an outer cap member  100  and an inner cap member  101 . The outer cap member  100  includes annular inner bead  102  which cooperates with the annular outer bead  73  of the applicator holder  64  to snap lock of the closure  67  to the applicator assembly  16 . The inner cap member  101  includes a sealing surface  103  which engages the tapered sealing surface  72  of the applicator holder  64  to prevent leakage of viscous material from the applicator assembly  16 . 
     Referring still again to FIG. 1, the reservoir assembly  18  includes an elongated, open-ended cylindrical reservoir member  91 , a passive piston  92  disposed in the rearward end of the reservoir member  91 , and an end cap  93  fixed in the rearward end of the reservoir member  91 . The forward end of the reservoir includes an external thread  94  which threadedly engages the internal thread  25  at the rearward end of the pump housing  21  to attach the reservoir assembly  18  thereto. In other embodiments of the invention, the reservoir assembly  18  and the pump housing  21  can be a single unitary member. 
     The details of the passive piston  92  of the reservoir assembly  18  is shown in the sectional view of FIG.  12 A and the elevational view of  12 B. The passive piston  92  includes an outwardly flared cup-like forward end  95  and an outwardly flared cup-like rearward end  96  which both share a common base wall  97 . A cylindrical projection  98  extends rearwardly from within the base wall  97 . 
     The operation of the device  10  will now be described with reference to FIGS. 13A and 13B. The operational description assumes that the device has been primed, i.e., viscous material  105  to be dispensed has been drawn into the cylinder  27 , the transfer tube  66 , and the applicator member  65  from the reservoir assembly  18 . 
     As shown in FIG. 13A, dispensing commences when the button  31  of the dispensing pump  22  is pressed. As the button  31  pivots through the aperture  24 , the rearward corners  62  of the button sidewalls  59  slidably engage the cam surfaces  55  (shown with broken lines) of the pump piston  29 , causing it to move rearwardly further into the cylinder  27 , thereby compressing the biasing element  30 . The cylinder volume reduction caused by the pump piston&#39;s  29  rearward movement into the cylinder produces a positive pressure in the cylinder  27  which closes the cylinder inlet valve  48  formed by the diaphragm member  46  and the cylinder inlet orifice  39 . The rearward movement of the pump piston  29  also opens the cylinder outlet valve  56  formed by the needle sealing element  28  and the pump piston outlet orifice  53 . These valving changes forces or meters a certain volume or dose of viscous material  105  contained in the cylinder  27  out the pump piston outlet orifice  53  into the rearward end  87  of the transfer tube  66 . The metered volume of viscous material  105  is generally determined by the rearward stroke distance of the pump piston  29  and the area of the cylinder  27 . 
     The flow of the metered volume of viscous material  105  causes the entire column of viscous material in the transfer tube  66  and applicator member  65  to flow forwardly. The viscous material flow in the transfer tube  66  opens the second diaphragm member  89  sealing the forward open end  86  of the transfer tube  66  thus, permitting a correspondingly similar volume of viscous material  105  to flow from the transfer tube  66  into the channels  82 ,  84 ,  85  of applicator member  65  and out onto the member&#39;s beveled outer surfaces  78 . 
     When the pump piston  29  reaches the end of its rearward stroke, viscous material flow ceases and the second diaphragm member  89  automatically reseals the forward open end  86  of the transfer tube  66 . When the button  31  is released as shown in FIG. 13B, the biasing force exerted by the biasing element  30  on the pump piston  29  forwardly moves the pump piston  29  to its original shallow position in the cylinder  27 . This forward movement of the pump piston  29  creates a negative pressure or vacuum in the cylinder  27  which opens the cylinder inlet valve  48 . Because rearward end of the cylinder  27  is immersed in the viscous material  105  stored in the reservoir member  91 , the vacuum draws this viscous material  105  into the cylinder  27 , thereby refilling it. As the viscous material  105  in the reservoir member  91  moves forwardly during refilling of the cylinder  27 , it creates a vacuum which moves the passive piston  92  forwardly thus, keeping the rearward end of the cylinder  27  immersed in the viscous material  105 . 
     While the foregoing invention has been described with reference to the above embodiments, various modifications and changes can be made without departing from the spirit of the invention. Accordingly, all such modifications and changes are considered to be within the scope of the appended claims.