초록 ▼

A dispensing pump for liquid or pasty products comprising a housing (2), a piston (6) arranged to move telescopically within the housing between rest and activated positions and a plastics spring (9) arranged to return the piston from its activated to its rest position. The plastics spring has a fol

A dispensing pump for liquid or pasty products comprising a housing (2), a piston (6) arranged to move telescopically within the housing between rest and activated positions and a plastics spring (9) arranged to return the piston from its activated to its rest position. The plastics spring has a folded, concertina configuration to provide the required return force for the piston. The spring also has end plates (91, 92), which can be adapted increased functionality. The whole pump may be moulded from a plastics material and has few component parts.

대표청구항 ▼

1. A dispensing pump for a container, the pump 1 comprising a housing2, held fixed in relation to the container and defining a pump chamber3 in communication with the inside of the container, a spout7, arranged to move telescopically with respect to the housing2 between a rest position and an activa

1. A dispensing pump for a container, the pump 1 comprising a housing2, held fixed in relation to the container and defining a pump chamber3 in communication with the inside of the container, a spout7, arranged to move telescopically with respect to the housing2 between a rest position and an activated position, a spring9, arranged to return the spout7 from its activated position to its rest position, an inlet valve5, adapted to prevent air entering the container but to allow product to enter the pump chamber3 from the container, and an outlet valve8, adapted to prevent air entering the pump chamber but to allow product to be dispensed from the pump chamber through the spout, characterised in that the spring9 is made from a plastics material and has a folded configuration, having a plurality of folds94.2. A dispensing pump according to claim 1, wherein the spring9 has at least one end plate91,92, which is adapted to constrain at least one of the inlet valve5 and outlet valve8.3. A dispensing pump according to claim 2, wherein at least one of the inlet valve5 and outlet valve8 comprises a valve member51,81, arranged to move within an associated valve chamber55,85 and the at least one end plate91,92 of the spring9 is adapted to retain the valve member51,81 within the valve chamber55,85.4. A dispensing pump according to claim 1, wherein the spout7 has an integral piston portion6, adapted to move telescopically within the housing2.5. A dispensing pump according to claim 4, wherein the spout7 further comprises a tubular seal10 adapted to fit inside the piston portion6, the tubular seal10 arranged to form a seal between the piston portion6 and the pump chamber3.6. A dispensing pump according to claim 5, wherein the tubular seal10 further defines a valve seat82 within a valve chamber85.7. A dispensing pump according to claim 1, wherein the plastics spring9 is manufactured by extruding a sheet having the required folded configuration and the sheet is then cut into segments to provide a plurality of springs.8. A dispensing pump according to claim 1, wherein the plastics spring9 has a cross section which conforms to the cross section of the pump chamber.9. A dispensing pump according to claim 1, wherein the folded spring (9) is an accordion fold.10. A dispensing pump according to claim 1, wherein the folded spring (9) is defined by a plurality of radius fold portions oriented in alternating oppositely opening directions.11. A dispensing pump according to claim 1, wherein the folded spring9 is defined by a plurality of substantially longitudinally disposed radius fold portions oriented in alternating oppositely opening directions.