US 12,173,806 B2
Flow rate control unit and water supply device with fine bubble generating arrangement incorporating flow rate control unit
Katsutoshi Nakano, Suita (JP); and Kazuya Ashibe, Hagi (JP)
Assigned to TOFLE CO., INC., Osaka (JP)
Filed by TOFLE CO., INC., Osaka (JP)
Filed on Apr. 21, 2023, as Appl. No. 18/304,949.
Claims priority of application No. 2022-072622 (JP), filed on Apr. 26, 2022.
Prior Publication US 2023/0341057 A1, Oct. 26, 2023
Int. Cl. F16K 17/30 (2006.01); B01F 23/237 (2022.01); B01F 35/71 (2022.01); B01F 35/75 (2022.01); F16K 3/26 (2006.01); F16K 3/34 (2006.01)
CPC F16K 17/30 (2013.01) [B01F 23/237611 (2022.01); B01F 35/71805 (2022.01); B01F 35/7547 (2022.01); F16K 3/26 (2013.01); F16K 3/34 (2013.01)] 12 Claims
OG exemplary drawing
 
1. A flow rate control unit comprising:
(a) a housing having
a hollow cylindrical wall configured to form thereinside a flow passage that guides liquid from an upstream side toward a downstream side,
an upstream wall disposed on the upstream side of the flow passage,
a downstream wall disposed on the downstream side of the flow passage,
an inlet opening formed in the upstream wall, and
an outlet opening formed in the downstream wall;
(b) a valve member disposed inside the hollow cylindrical wall and between the upstream wall and the downstream wall,
the valve member being moveable between a most upstream position at which a movement of the valve member toward the upstream side is restricted by the upstream wall and a most downstream position at which a movement of the valve member toward the downstream side is restricted by the downstream wall,
the valve member having a pressure receiving portion that faces the inlet opening and receives a force, in a direction toward the downstream side, from the liquid flowing into the flow passage from the inlet opening; and
(c) an elastic biasing member configured to bias the valve member toward the most upstream position and deform such that the movement of the valve member toward the downstream side increases in response to a force received at the pressure receiving portion from the liquid increases,
(d) wherein the valve member or the cylindrical wall forms a first guide flow passage that guides the liquid flowing into the flow passage from the inlet opening to the downstream side of the valve member,
(e) wherein the valve member cooperates with the downstream wall to form, between the valve member and the downstream wall, a second guide flow passage that guides the liquid from the first guide flow passage to the outlet opening,
(f) wherein the second guide flow passage cooperates with the valve member and the downstream wall to constitute a variable resistance portion that gives a resistance to the liquid passing through the second guide flow passage, the resistance increasing as the valve member moves from the upstream wall toward the downstream side,
(g) wherein the first guide flow passage extends through the valve member along a central axis of the flow passage,
(h) wherein the valve member has an inner hollow cylindrical portion extending from the upstream side toward the downstream side along the central axis and having an opening at a downstream side end portion of the valve member,
(i) wherein the downstream wall has an outer hollow cylindrical portion extending from the downstream side toward the upstream side along the central axis and having an opening at an upstream side end portion of the cylindrical portion,
(j) wherein an outer diameter of the inner hollow cylindrical portion is smaller than an inner diameter of the outer hollow cylindrical portion,
(k) the inner hollow cylindrical portion is insertable inside the outer hollow cylindrical portion and, when inserted, leaving a gap extending inside the outer hollow cylindrical portion and forming the second guide cylindrical passage between the inner hollow cylindrical portion and the outer hollow cylindrical portion, and
(l) wherein a length of the second guide flow passage increases with the movement of the valve member from the upstream side toward the downstream side, which in turn increases a resistance applied to the liquid passing through the second guide flow passage.