US 12,031,311 B2
Flush water tank device and flush toilet apparatus provided with the same
Hideki Tanimoto, Kitakyushu (JP); Koki Shinohara, Kitakyushu (JP); Kenji Hatama, Kitakyushu (JP); and Seika Tatsuoka, Kitakyushu (JP)
Assigned to TOTO LTD., Kitakyushu (JP)
Filed by TOTO LTD., Kitakyushu (JP)
Filed on Aug. 26, 2022, as Appl. No. 17/822,592.
Claims priority of application No. 2021-139355 (JP), filed on Aug. 27, 2021.
Prior Publication US 2023/0065471 A1, Mar. 2, 2023
Int. Cl. E03D 1/34 (2006.01); E03D 1/30 (2006.01)
CPC E03D 1/34 (2013.01) [E03D 1/304 (2013.01)] 7 Claims
OG exemplary drawing
 
1. A flush water tank device for supplying flush water to an upper spout port above a retained water surface in a flush toilet main body and a lower spout port below the retained water surface, the flush water tank device comprising:
a flush water tank main body;
a discharge valve that performs switching between ejection and stopping of the flush water from the lower spout port by performing switching between discharge and stopping of the flush water retained in the flush water tank main body;
a water pressure driving mechanism that drives the discharge valve with a water supply pressure of the flush water supplied from a water supply source;
a first on-off valve that performs switching between an ejection state and an ejection stopped state of the flush water, which has been supplied from the water supply source, from the upper spout port on the basis of a user's operation;
a second on-off valve that performs switching between water supply and stopping of the flush water, which has been supplied from the water supply source, to the water pressure driving mechanism; and
a delay valve opening mechanism that causes the second on-off valve to open with a delay of predetermined time after water ejection from the upper spout port is started, using a part of the flush water introduced via the first on-off valve, to supply the flush water to the water pressure driving mechanism,
wherein the delay valve opening mechanism includes a balance float that is disposed to receive a buoyant force from the flush water retained in the flush water tank main body, a water receiving portion that is configured such that a part of the flush water introduced via the first on-off valve flows into the water receiving portion, and a second on-off valve driving mechanism that is connected to the balance float and the water receiving portion, and
wherein the second on-off valve driving mechanism causes the second on-off valve to open when the weight of the water receiving portion increases due to flowing-in of the flush water and overcomes the buoyant force acting on the balance float.