Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
  • B05B—SPRAYING APPARATUS; ATOMISING APPARATUS; NOZZLES
  • B05B11/00—Single-unit hand-held apparatus in which flow of contents is produced by the muscular force of the operator at the moment of use
  • B05B11/0005—Components or details
  • B05B11/0037—Containers
  • B05B11/0039—Containers associated with means for compensating the pressure difference between the ambient pressure and the pressure inside the container, e.g. pressure relief means
  • B05B11/0041—Containers associated with means for compensating the pressure difference between the ambient pressure and the pressure inside the container, e.g. pressure relief means compensating underpressure without contact of the fluid remaining in the container with the atmospheric air
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
  • B05B—SPRAYING APPARATUS; ATOMISING APPARATUS; NOZZLES
  • B05B11/00—Single-unit hand-held apparatus in which flow of contents is produced by the muscular force of the operator at the moment of use
  • B05B11/01—Single-unit hand-held apparatus in which flow of contents is produced by the muscular force of the operator at the moment of use characterised by the means producing the flow
  • B05B11/10—Pump arrangements for transferring the contents from the container to a pump chamber by a sucking effect and forcing the contents out through the dispensing nozzle
  • B05B11/1001—Piston pumps
  • B05B11/1023—Piston pumps having an outlet valve opened by deformation or displacement of the piston relative to its actuating stem
  • B05B11/1025—Piston pumps having an outlet valve opened by deformation or displacement of the piston relative to its actuating stem a spring urging the outlet valve in its closed position
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
  • B05B—SPRAYING APPARATUS; ATOMISING APPARATUS; NOZZLES
  • B05B11/00—Single-unit hand-held apparatus in which flow of contents is produced by the muscular force of the operator at the moment of use
  • B05B11/01—Single-unit hand-held apparatus in which flow of contents is produced by the muscular force of the operator at the moment of use characterised by the means producing the flow
  • B05B11/10—Pump arrangements for transferring the contents from the container to a pump chamber by a sucking effect and forcing the contents out through the dispensing nozzle
  • B05B11/1042—Components or details
  • B05B11/105—Sealing arrangements around pump actuating stem

Definitions

• the present invention relates to an improved manually operable pump for dispensing quantities of a fluid substance in the form of liquids, creamy substances or the like through the hollow operating stem of the pump.
• the pump enables the substance to be dispensed when in any position while preventing, under normal conditions of use, the passage of fluids (air, gas or liquid) between the outer surface of the stem and the adjacent surface of the hole in the pump ring cap through which said stem extends and is translatable.
• air passes through a passageway provided in the pump body or between the pump and the ring cap on which the pump is mounted, the air always passing between the outer surface of the hollow stem and the opposing surface of the hole provided in the pump ring cap through which the stem passes.
• the passageway existing between the outer surface of the pump hollow stem and the surface of the hole in the ring cap through which the stem passes presents problems, one of which is that the external air which penetrates into the container can deteriorate the characteristics of the fluid substance contained therein, another being the fact that the fluid can seep or leak to the outside of the container through the said passageway when the container and pump lie in a horizontal position or with the pump facing downwards from the container.
• the fluid substances to be dispensed by dispensers for their use must be contained in containers in which a pressurized gas is also present to normally expel the substances under pressure through dispensing devices acting as manually operable aerosol valves, the opening or closure of which results in continuous dispensing or prevents dispensing of the substance respectively.
• pump-type dispensers are also known for dispensing a fluid substance and a pressurizing gas from a container containing the substance and the pressurizing gas hermetically sealed therein.
• Such dispensers have structures which seem similar to those of the pumps commonly used on containers which are not internally pressurized, but which are clearly distinct from them.
• pump-type dispensers have substantially a form similar to that of a pump but differ therefrom by comprising a cup-shaped body, the cavity of which is sealed by a ring cap sealedly applied to the mouth of a container in which a fluid substance and a pressurized gas are contained.
• the cup-shaped body presents a chamber with a hole through which the fluid substance rises into the chamber by the effect of the pressure present in the container.
• This chamber is bounded by a piston sealedly translatable along the inner surface of the cup-shaped body: a hollow stem connected to the piston emerges from and is sealedly translatable through a hole provided in the pump ring cap. Under rest conditions in which the piston is urged by a compressed spring reacting against the cup-shaped body, the cavity in the pump stem is closed by a unidirectional valve.
• the main object of the present invention is to provide a pump which does not allow air, gas or liquids to pass between the outer surface of the respective stem and the surface of the hole in the pump ring cap, under any condition in which the pump is used.
• Another object is to provide a pump which can be sealedly mounted on a container to define therewith a hermetically sealed space, from which however the pump can withdraw and dispense quantities of the fluid substance.
• a pump comprising a cup- shaped body having an open end on which a ring cap is sealedly applied, and a closed end in which a hole is provided through which the fluid substance can, via a unidirectional valve, enter a lower pump chamber from which the substance can be dispensed to the outside of the pump, said lower chamber being bounded by an annular piston sealedly translatable both along the inner surface of the cup-shaped body and along the outer surface of a hollow operating stem for dispensing the fluid substance, said stem extending from and being axially translatable through a hole provided in said ring cap which with said piston defines an upper pump chamber, characterised in that, under any condition in which the pump is used, the outer surface of the stem seals against the opposing surface of the hole in the ring cap, there being provided in the cup-shaped body at least one passageway which connects said upper chamber to the outside of said cup-shaped body.
• a new and particularly interesting utilization of the pump of the present invention is that when the pump is mounted on a container such as to define therewith a hermetically sealed space in which the fluid substance present generates a pressurized gaseous phase, in particular there being present in said hermetically sealed space at least one low- boiling liquid having a saturated vapour pressure less than 1.00 kg/cm 2 at 15 0 C and less than 2.8 kg/cm 2 at 37.8 0 C which generates a slight vapour pressure at an ambient temperature of 21 0 C.
• Low-boiling liquids are fluid chemical substances which have a boiling point between +15 0 C and +85 0 C and develop a pressure of 1 atm (about 760 mm. Hg).
• Advantageously usable low-boiling liquids are those chosen from the group consisting of isopentane, isohexane, N-pentane, N-hexane, dichloromethane, monochloropropane, 1-1-dichloroethane, 2- chlorobutane, trichloro-fluoro-methane CFC 11 , trichloro-tifluoro-ethane CFC 113, ethyl ether, methylene-dimethylether, dimethoxymethane and acetone.
• FIGS. 1 to 4 are longitudinal sections through a preferred embodiment of the pump shown respectively in its rest state, at the commencement of the dispensing stage, at the end of its dispensing stroke, and in an intermediate position of the stage in which the liquid substance is drawn into the pump lower chamber.
• Figures from 1 to 4 show a pump the structure of which is of known type, except for the following details.
• the pump has a structure totally similar or equal to that of the pumps illustrated in the prior patents specified in the introduction to this description, and of which the teachings are incorporated herein for reference: the pump structure and operation will therefore not be described in detail for brevity.
• the pump comprises a cup-shaped body 1 closed at one end by a ring cap 2 and presenting at its other end a hole 3 which opens into the hollow space defined by a container (not shown in the drawings) on the mouth of which the pump ring cap 2 is mounted and sealed in any known manner (for example by crimping, etc.).
• the interior of the cup-shaped body houses an annular piston 4, which is translatable along and seals against the inner surface of the cup- shaped body and respectively against the outer surface of a hollow stem 5 translatable axially through a hole provided in the flange 2 and along the cavity of which the fluid substance can be expelled to the outside (and hence used), having been previously drawn into a lower pump chamber 8 lying between the lower surface (with respect to the drawings) of the piston 4 and the pump intake hole 3 which houses a unidirectional valve consisting of a ball 11 movable between a sealing seat provided at the upper end of the hole 3 and stop elements 13 forming part of the pump body.
• An upper chamber 9 is defined in the cup-shaped body between the top of the piston 4 and the flange 2 and communicates with the outside of the cup-shaped body 1 via a hole or passageway 10 provided directly in the cup-shaped body: in this manner, when the pump is sealedly mounted on the mouth of a container, the pressure in the upper pump chamber 9 is always equal to the pressure in the container on which the pump is sealedly mounted.
• a hermetic seal exists between the outer surface of the stem 5 and the opposing surface of the hole in the ring cap 2 through which the stem extends and is translatable, and in the case of the embodiment shown in the figures is provided by a gasket or O-ring 12 of rubber or a suitable elastomeric material (although the seal between the stem and the hole in the ring cap can be provided in a different manner, for example by simply providing a lip, not shown for simplicity, forming part of the ring cap 2, which can be formed of deformable plastic material, such as polyethylene, polypropylene etc.).
• the main and essential characteristic of the pump of the present invention is that its hollow stem 5 is always housed and translatable in a sealed state (in all conditions under which the pump is used or is at rest) within the guide hole in the ring cap 2, and that in addition the cup-shaped body 1 of the pump is provided with the hole or passageway 10 at the upper chamber 9 of the pump body.
• the upper pump chamber 9 cannot enable liquids, air or gas to seep between the outer surface of the stem and the ring cap hole through which this stem extends, and the ring cap 2 is mounted hermetically sealed on the mouth of a container (not shown for simplicity), there are no undesirable leakages or seepages of gas, air or fluid out of the stem.
• the pressure in the upper pump chamber 9 is always equal (because of the presence of the passageway 10) to the pressure in the container on which the pump is mounted hermetically sealed.
• the pump is mounted on a deformable bag which is squeezed by atmospheric pressure; or if the pump is mounted on a container also containing a pressurized gas, of known type.
• a particularly interesting and advantageous utilization of the pump is that in which a rigid container (on which the pump is mounted such as to define a hermetically sealed space in the container interior) contains a fluid, semidense or pasty substance mixed with low-boiling liquids able to generate a slight vapour pressure under normal conditions of use, i.e. at about 21 0 C.
• Low-boiling liquids are liquids having a saturated vapour pressure less than 1.00 kg/cm 2 at 15 0 C and less than 2.8 kg/cm 2 at 37.8O 0 C.
• Low-boiling liquids are fluid chemical substances which have a boiling point between +15 0 C and +85 0 C and develop a pressure of 1 atm (about 760 mm.Hg).
• Preferred low-boiling liquids are those chosen from the group consisting of isopentane, isohexane, N-pentane, N-hexane, dichloromethane, monochloropropane, 1-1-dichloroethane, 2- chlorobutane, trichloro-fluoro-methane CFC 11 , trichloro-tifluoro-ethane CFC 113, ethyl ether, methylene-dimethylether, dimethoxymethane and acetone.
• the low-boiling liquid present in the container evaporates from its liquid phase present in the mixture and restores the desired pressure within the container (slightly higher than atmospheric), to prevent formation of a vacuum which would hinder continuation of dispensing from the rigid container.
• a particularly important characteristic of the pump described with reference to the drawings is that, when at rest, the pressure in the pump lower chamber 8 is equal to that in the upper chamber 9, so that the pressure acting on the upper and lower surfaces of the piston 4 is the same. It follows that to dispense the fluid substance through the cavity in the stem (on the free end of which, external to the pump, a button of any known type is mounted for simplicity) the pressing force which has to be exerted on the stem (examining the figures from Figure 1 to Figure 3) is only that required to overcome the thrust of the two springs 20 and 30 and to compress the fluid substance collected and contained in the chamber 8 to cause a seal lip 40 on the piston 4 to separate from a corresponding seal seat in a collar 50 rigid with and hence forming part of the stem 5. Pump operation therefore does not require a large force, and is equal to that required to dispense by pumps of known type mounted in known unsealed manner on fluid substance containers.
• the return of the pump from the position reached at the end of its operating travel to its rest position ( Figure 1 ) by passing through an intake stage takes place smoothly merely under the thrust of the springs, and not with extreme difficulty as would occur with the pump-type dispensers of US 3,211 ,346A, US 4,511 ,069A and GB 1537436A, in which a hermetically sealed upper chamber is provided above the piston of each chamber (i.e. an aperture such as that indicated by the number 10 in the accompanying drawings does not exist).
• the pump of the present invention is advantageously usable for dispensing pressurized fluids developing a saturated vapour pressure less than 2.8 kg/cm 2 at 54.4 0 C.

Landscapes

• Containers And Packaging Bodies Having A Special Means To Remove Contents (AREA)
• Closures For Containers (AREA)
• Reciprocating Pumps (AREA)
• Jet Pumps And Other Pumps (AREA)

Applications Claiming Priority (2)

Publications (2)

Family

ID=34956772

Family Applications (1)

Country Status (6)

Families Citing this family (4)

Family Cites Families (11)

• 2005
  • 2005-02-09 IT IT000180A patent/ITMI20050180A1/it unknown
  • 2005-12-13 RU RU2007121149/12A patent/RU2387485C2/ru not_active IP Right Cessation
  • 2005-12-13 WO PCT/EP2005/056754 patent/WO2006084519A1/en active Application Filing
  • 2005-12-13 CN CN2005800413817A patent/CN101068624B/zh not_active Expired - Fee Related
  • 2005-12-13 EP EP05821749.8A patent/EP1863590B1/de active Active
  • 2005-12-13 BR BRPI0518918-7A patent/BRPI0518918A2/pt not_active Application Discontinuation

Non-Patent Citations (1)

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