Search

EP-4739442-A1 - PLASTIC SPRING

EP4739442A1EP 4739442 A1EP4739442 A1EP 4739442A1EP-4739442-A1

Abstract

The invention relates to a plastic spring (11) for use in a pump dispenser (13), having a first spring element (15) and a second spring element (17), which can be pushed into one another in the axial direction, wherein the spring force is generated in that when the two spring elements (15, 17) are pushed into one other in the axial direction, the first and/or the second spring element (15, 17) elastically expands in the radial direction. The first and the second spring element have, respectively, a first and second cone (15, 17) with a first and second tip (15, 17), wherein the first and second tip (19, 21) face one another and the first cone (15) can be axially pushed into the second cone (17) or the second cone (17) can be axially pushed into the first cone (15).

Inventors

  • ZMÖLNIG, Christian

Assignees

  • Alpla-Werke Alwin Lehner GMBH & Co.KG

Dates

Publication Date
20260513
Application Date
20240704

Claims (12)

  1. 1 . Plastic spring (11) for use in a pump dispenser (13) comprising - a first spring element (15) and a second spring element (17), which can be pushed into one another in the axial direction, wherein the spring force is generated in that when the two spring elements (15, 17) are pushed into one another in the axial direction, the first and/or the second spring element (15, 17) is elastically expanded in the radial direction, characterized in that the first and the second spring element have a first and a second cone (15, 17) with a first and a second tip (15, 17), the first and second tips (19, 21) facing one another and the first cone (15) being axially displaceable into the second cone (17) or the second cone (17) being axially displaceable into the first cone (15).
  2. 2. Plastic spring according to claim 1, characterized in that the first cone is a truncated cone (15) with a first end (19) or the first tip with a smaller diameter and a second end (23) with a larger diameter, which is formed from at least a first lateral surface and is open at its first end (19), wherein at least one slot (26) extending from the first to the second end (19, 23) is provided on the first lateral surface.
  3. 3. Plastic spring according to claim 1, characterized in that the second cone is a truncated cone (17) with a third end (21) or the second tip with a smaller diameter and a fourth end (25) with a larger diameter, which is formed from at least a second lateral surface and is open at its third end (21), wherein at least one slot (26) extending from the third to the fourth end (21, 25) is provided on the second lateral surface.
  4. 4. Plastic spring according to claim 2 or 3, characterized in that the at least one slot (26) is closed at the first or third end and is open at the second or fourth end (23,25).
  5. 5. Plastic spring according to one of claims 2 to 4, characterized in that four slots (26) are provided on the first or second cone (15, 17), wherein a spring wing (27) is formed between each of the slots (26).
  6. 6. Plastic spring according to one of the preceding claims, characterized in that a shoulder (28) is provided at the second or at the fourth end (23, 25), which limits the axial movement of the two cones (15, 17) relative to one another.
  7. 7. Plastic spring according to one of the preceding claims, characterized in that the first and the second cone (15,17) have substantially the same height (29,30).
  8. 8. Plastic spring according to one of the preceding claims, characterized in that the first and the second cone are realized as a first and second sleeve (15,17).
  9. 9. Plastic spring according to one of claims 2 to 8, characterized in that a first or a second holding element (31a, 31b) adjoins the first or third end (19, 21).
  10. 10. Plastic spring according to claim 9, characterized in that the first and second holding element are a first and second cylinder jacket (31a, 31b) which can be positively connected to components of the pump dispenser (13).
  11. 11. Plastic spring according to one of the preceding claims, characterized in that the plastic spring (11) is made of polypropylene, polyethylene, polyoxymethylene or polyamide.
  12. 12. Pump dispenser (13) for the dosed removal of a liquid from a container onto which the pump dispenser (13) can be placed, comprising a housing (35) which is held on the container by a cap (37) and in which a dosing chamber (39) is formed, a pump head (41) which is movable up and down relative to the housing (35) along the longitudinal axis (43) of the dispenser (13) between a first and second position to carry out a pump stroke, a piston (45) which is fixed to the pump head (41) and is movable in the dosing chamber (39) to convey the liquid, a dispenser opening (47) which is connected to the dosing chamber (39) and through which dosed liquid can leave the pump dispenser (13), a spring (11) which resets the pump head (41) relative to the housing (35), a suction pipe (51) with which liquid is sucked from the container into the dosing chamber (39) and a valve in the form of a first and second ball (49a, 49b), which balls (49a, 49b) define the conveying direction of the liquid from the container into the dispenser opening (37) and block conveying in the opposite direction, characterized in that the spring is a plastic spring (11) according to one of the preceding claims and the first and second balls (49a, 49b) are made of plastic.

Description

plastic spring field of the invention The invention relates to a plastic spring for use in a pump dispenser according to the preamble of claim 1 and a pump dispenser according to the preamble of claim 12. State of the art Pump dispensers are used to remove a liquid, which can also have a high viscosity (creams or gels), from a storage container by pressing a dispenser head downwards. The dispenser extension is formed on the dispenser head and therefore moves with the dispenser head. A metal spring is integrated into the dispenser to reset the dispenser head. The valve function, which is necessary for the liquid to be pumped into the dispenser extension when the head is pressed and for liquid to be sucked into the pump dispenser when the head is reset, is implemented using metal or glass balls. A separate disposal of such pump dispensers known from the state of the art is not possible or only possible with great effort, since the metal spring and the valve balls would have to be removed from the pump dispenser. There are already pump dispensers with plastic balls with a valve function and plastic springs with an adapted design. In order for the plastic spring to function reliably and to have good long-term load-bearing capacity, the pump dispenser must be adapted to the plastic spring. This involves considerable effort, as a pump dispenser must be specially developed and produced for the plastic spring. Furthermore, classic plastic springs, typically designed as spiral spring elements, are very complex to manufacture. Complex injection molding tools and manufacturing technology are necessary to be able to produce such helix spring structures. task of the invention The disadvantages of the described state of the art result in the task of creating a plastic spring which is simple in construction and can be produced and manufactured as easily as possible and does not require complex and accordingly expensive Adjustment of the pump dispenser and can be compressed and decompressed without annoying jerky movements. Description The solution to the stated problem is achieved in a plastic spring for use in a pump dispenser by the features stated in the characterizing section of patent claim 1. Further developments and/or advantageous embodiments are the subject of the dependent patent claims. The invention is preferably characterized in that the first and second spring elements have a first and second cone with a first and second tip, respectively, the first and second tips facing each other and the second cone being axially displaceable into the second cone or the second cone being axially displaceable into the first cone. By providing the two cones, the plastic spring is particularly simple in construction and can be manufactured inexpensively. Since the spring consists of only two components, it works particularly reliably and a large number of pumping cycles are ensured. In a preferred embodiment of the invention, the first cone is a truncated cone with a first end or the first tip with a smaller diameter and a second end with a larger diameter, which is formed from at least a first lateral surface and is open at its first end, with at least one slot extending from the first to the second end being provided on the first lateral surface. The conical shape makes it easy for the spring force of the spring to be greatest when the penetration depth is greatest. As a result, the restoring force is greatest when the suction of product into the dosing chamber begins and the highest suction force is required. It is of course also conceivable for the second cone to be a truncated cone with a third end or the second tip with a smaller diameter and a fourth end with a larger diameter, which is formed from at least a second lateral surface and is open at its third end, with at least one slot extending from the third to the fourth end being provided on the second lateral surface. For the function of the plastic spring, it makes no difference on which of the two cones the at least one slot is provided. It is advantageous if the at least one slot is closed at the first or third end and is open at the second or fourth end. This forms at least one spring wing on the cone shell, which is located at the second or fourth end can be bent open. A joint is formed at the first or third end around which the spring wing can be pivoted in a radial direction. Because the joint is bent in the circumferential direction of the cone, it has a restoring force and the spring wing is pressed into its original position. The spring wing can exert a compressive force on the other cone at its open end, which pushes the inner cone out of the outer cone. This creates an axial force that pushes the inner cone out of the outer cone. In another particularly preferred embodiment of the invention, four slots are provided on the first or second cone, with a spring wing being formed between each slot. This number of slots or spring wings generates an optimal