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EP-4741630-A1 - SINUSOIDAL PUMP WITH BLOCKING SLIDE, AND PRODUCTION METHOD

EP4741630A1EP 4741630 A1EP4741630 A1EP 4741630A1EP-4741630-A1

Abstract

A blocking slide (38) for a pump comprises: a rotor contact area (48) designed to rest against a wave-shaped rotor collar of the pump, wherein the rotor contact area (48) comprises: lateral rotor contact surfaces (50) which are designed to rest in each case against side surfaces of the rotor collar, and an upper rotor contact surface (52) which is designed to rest against a radially outward-facing shell surface of the rotor collar, wherein the lateral rotor contact surfaces (50) are each implemented as conically rounded surfaces, wherein a first radius of curvature (R 1 ) in a lower region of the lateral rotor contact surfaces (50), which is remote from the upper rotor contact surface (52), is smaller than a second radius of curvature (R 2 ) in an upper region of the lateral rotor contact surfaces (50), which is adjacent to the upper rotor contact surface (52).

Inventors

  • DAMBACHER, FRANK

Assignees

  • Watson Marlow GmbH - MasoSine Division

Dates

Publication Date
20260513
Application Date
20251105

Claims (12)

  1. A blocking slide (38) for a pump (10), comprising: a rotor contact area (48) designed to rest against a wave-shaped rotor collar (18) of the pump (10), wherein the rotor contact area (48) comprises: lateral rotor contact surfaces (50) which are designed to rest in each case against side surfaces of the rotor collar (18), and an upper rotor contact surface (52) which is designed to rest against a radially outward-facing shell surface of the rotor collar (18), wherein the lateral rotor contact surfaces (50) are each implemented as conically rounded surfaces, wherein a first radius of curvature (R 1 ) in a lower region of the lateral rotor contact surfaces (50), which is remote from the upper rotor contact surface (52), is smaller than a second radius of curvature (R 2 ) in an upper region of the lateral rotor contact surfaces (50), which is adjacent to the upper rotor contact surface (52).
  2. A pump (10), with a rotor (14) which can rotate about an axis of rotation and which comprises a rotor hub (16) and a rotor collar (18) which extends from the rotor hub (16) in a radial direction and revolves in a wave-like manner, a pump housing (12) which, together with the rotor (14), forms a pump chamber (20) which connects a first inlet/outlet chamber to a second inlet/outlet chamber, and a blocking device (22) which is arranged between the first inlet/outlet chamber and the second inlet/outlet chamber and which comprises a blocking slide (38) which blocks the pump chamber (20) in the axial direction on both sides of the rotor collar (18), wherein the blocking slide (38) has lateral rotor contact surfaces (50) each of which rest against side surfaces of the rotor collar (18), and has an upper rotor contact surface (52) which rests against a radially outward-facing shell surface of the rotor collar (18), wherein the lateral rotor contact surfaces of the blocking slide (38) are each implemented as conically rounded surfaces, wherein a first radius of curvature (R 1 ) of the lateral rotor contact surfaces (50) in a radially inner region, which is close to the rotor hub (16), is smaller than a second radius of curvature (R 2 ) of the lateral rotor contact surfaces (50) in a radially outer region which adjoins the upper rotor contact surface (52).
  3. The pump (10) according to claim 2, wherein the upper rotor contact surface (52) of the blocking slide (38) is a concavely curved surface with a third radius of curvature (R 3 ) which corresponds to the radius of curvature of the radially outward-facing shell surface of the rotor collar (18).
  4. The pump (10) according to any one of claims 2 or 3, wherein a lower rotor contact surface (54) of the blocking slide (38) is in contact with a radially outward-facing shell surface of the rotor hub (16), and wherein the lower rotor contact surface (54) of the blocking slide (38) is a concavely curved surface with a fourth radius of curvature (R 4 ), which corresponds to the radius of curvature of the radially outward-facing shell surface of the rotor hub (16).
  5. The pump (10) according to any one of claims 2 to 4, wherein the blocking slide (38) is made from a plastic material and comprises an outer shell (42) and reinforcing ribs (44) so that cavities (46) are formed in the blocking slide (38).
  6. The pump (10) according to claim 5, wherein the outer shell (42) and/or the reinforcing ribs (44) of the blocking slide (38) are made from a plastic material with a glass fibre content, such as glass fibre-reinforced polyamide.
  7. The pump (10) according to any one of claims 4 or 5, wherein at least some of the cavities (46) of the blocking slide (38) are filled with a filling material.
  8. A method for producing a blocking slide (38) for a sinusoidal pump (10), comprising: providing a glass fibre reinforced plastic material suitable for processing by injection moulding; producing the blocking slide (38) by injection moulding the glass fibre reinforced plastic material, wherein the blocking slide (38) has a rotor contact area (48), comprising: lateral rotor contact surfaces (50) which are designed to rest in each case against side surfaces of a rotor collar (18), and an upper rotor contact surface (52), which is designed to rest against a radially outward-facing shell surface of the rotor collar (18), wherein the lateral rotor contact surfaces (50) are each implemented as conically rounded surfaces, wherein a first radius of curvature (R 1 ) of the lateral rotor contact surfaces (50) in a lower region, which is remote from the upper rotor contact surface (52), is smaller than a second radius of curvature (R 2 ) of the lateral rotor contact surfaces (50) in an upper region which is adjacent to the upper rotor contact surface (52).
  9. The method according to claim 1, wherein the step of producing the blocking slide (38) by injection moulding the glass fibre reinforced plastic material comprises producing a blocking slide (38) having an outer shell (42) and having at least one reinforcing rib (44) located within the outer shell (42) so that that cavities (46) are formed within the outer shell (42), and wherein the method further comprises: filling the cavities (46) in the blocking slide (38) with a filling material.
  10. A method for producing a blocking slide (38) for a sinusoidal pump (10), comprising: providing a plastic material suitable for processing by injection moulding, wherein the plastic material is approved for food applications when processed by injection moulding; producing the blocking slide (38) by injection moulding the plastic material.
  11. The method according to claim 10, wherein the plastic material is a glass fibre reinforced plastic material.
  12. The method according to any one of claims 10 or 11, wherein the step of producing the blocking slide (38) by injection moulding comprises producing a blocking slide (38) having an outer shell (42) and having at least one reinforcing rib (44) located within the outer shell (42) so that that cavities (46) are formed within the outer shell (42), and wherein the method further comprises: filling the cavities (46) in the blocking slide (38) with a filling material.

Description

Background of the invention The present invention relates to a sinusoidal pump and a production method for a blocking slide for a sinusoidal pump. Sinusoidal pumps are characterised in that a rotor has a collar which extends in a radial direction and revolves in a wave-shaped or sinusoidal manner. In a pump housing, a common inlet and outlet chamber is provided in which a blocking device is formed which engages around the rotor collar and prevents backflow of the fluid to be pumped within the common inlet and outlet chamber. This blocking device can comprise a blocking slide which is placed on the rotor collar and has a slot through which the rotor collar slides. Such slides are usually milled from a plastic blank. To seal the pump chamber, it is essential that the best possible (fluid-tight) contact between the slide and the rotor collar can be achieved. However, the milled slides only allow the production of flat contact surfaces in each case. It is therefore an object of the present invention to provide an improved blocking device for a sinusoidal pump and an improved production method by means of which backflow of fluid to be pumped can be further reduced. It is a further object of the present invention to provide a production method for a blocking slide that can be used in pumps in the food industry. These objects are achieved by a blocking slide according to claim 1, by a pump according to claim 2 and by a production method according to claim 8 or claim 10. According to one embodiment, a blocking slide for a pump, such as a sinusoidal pump, comprises a rotor contact area designed to rest against a wave-shaped rotor collar of the pump. The blocking slide can be a substantially cuboid component with a slot which is provided in one side and forms the rotor contact area and is designed to be placed on the rotor collar. The rotor contact area comprises lateral rotor contact surfaces which are designed to rest against each of the side surfaces of the rotor collar, and an upper rotor contact surface which is designed to rest against a radially outward-facing shell surface of the rotor collar. The lateral and upper rotor contact surfaces thus form the aforementioned slot in the blocking slide which can be placed on the rotor collar and which is in contact with the rotor collar during operation of the pump in order to seal a pump chamber of the pump and prevent backflow of the fluid to be conveyed from an outlet region back to an inlet region. The lateral rotor contact surfaces are each implemented as conically rounded surfaces, wherein a first radius of curvature in a lower region of the lateral rotor contact surfaces, which is remote from the upper rotor contact surface, is smaller than a second radius of curvature in an upper region of the lateral rotor contact surfaces, which is adjacent to the upper rotor contact surface. This allows to achieve a large-area contact between the lateral rotor contact surfaces and the wave-shaped rotor collar since, in the radially outwardly extending, wave-shaped rotor collar, a radially inner region has a shorter circumference and thus a greater curvature of the wave shape than a radially outer region in which the wave shape is stretched over a longer circumference. According to another embodiment, a pump is provided with a rotor rotatable about an axis of rotation, which comprises a rotor hub and a wave-shaped revolving rotor collar extending radially from the rotor hub, with a pump housing which together with the rotor forms a pump chamber which connects a first inlet/outlet chamber with a second inlet/outlet chamber, and with a blocking device which is arranged between the first inlet/outlet chamber and the second inlet/outlet chamber and comprises a blocking slide which blocks the pump chamber in the axial direction on both sides of the rotor collar. Such a sinusoidal pump can be used in particular for conveying foodstuffs since the pump chamber can be easily cleaned and since by providing the pump chamber between a radially outer side of the rotor and a pump housing, contamination of the fluid to be pumped, for example by lubricating oil or by abrasion particles from the drive shaft or the drive unit of the pump, can be avoided. The blocking slide has lateral rotor contact surfaces, each of which rests against the side surfaces of the rotor collar, and the blocking slide also has an upper rotor contact surface which rests against a radially outward-facing shell surface of the rotor collar. The lateral rotor contact surfaces of the blocking slide are each implemented as conically rounded surfaces, wherein a first radius of curvature of the lateral rotor contact surfaces in a radially inner region, which is close to the rotor hub, is smaller than a second radius of curvature of the lateral rotor contact surfaces in a radially outer region which is adjacent to the upper rotor contact surface. As a result, a flat contact over the entire radial extent of the rotor collar c