Powder flow-rate measuring and controlling apparatus

Claim 2

A powder flow-rate measuring apparatus which is characterized by comprising a aetecting pipe line having an inlet and an outlet, a nozzle for blowing a conveying gas into said inlet of detecting pipe line, means for measuring a flow rate of said conveying gas fea to saia nozzle, means for controlling a flow rate of saia conveying gas, means for introducing a powder into saia inlet of detecting pipe line, and a aevice for detecting the pressure difference between a pressure at an inlet side pressure detecting port arrangea upstream tne outlet of said nozzle and a pressure at an outlet side pressure aetecting port arranged at said outlet of detecting pipe line.

Claim 3

A powder flow-rate measuring apparatus according to Claim 1 wherein said inlet side pressure detecting port is communicatea with immediately oownstream of said means for measuring a flow rate.

Claim 4

A powder flow-rate measuring apparatus according to anyone of Claims 1 ana 2 wnerein means for modulating the pressure in the outlet of aetecting pipe line and/or means for moaulating tne pressure in the inlet of detecting pipe line is provided.

Claim 5

A powder flow-rate measuring apparatus according to Claim 3 wnerein said means for modulating the pressure in tne outlet of detecting pipe line is an injector consisting of a throat ana a driving nozzle.

Claim 6

A powder flow-rate measuring apparatus comprising a detecting pipe line having an inlet and an outlet, a nozzle for blowing a conveying fluid into said inlet of detecting pipe line, and means for detecting a pressure difference between a pressure at an inlet side pressure detecting port arranged upstream the outlet of said nozzle and a pressure at an outlet sioe pressure oetecting port arranged at said outlet of detecting pipe line, which is characterized by being provided with means tor separating a part of said conveying fluia to feed said inlet side pressure detecting port, means for modulating the pressure in the outlet of detecting pipe line ana/or means for modulating the pressure in the inlet of detecting pipe line, saia means for modulating the pressure in the outlet of aetecting pipe line being an injector consisting of a throat ana a driving nozzle, and an automatic control valve wherein said pressure difference between a pressure at the inlet side pressure detecting port and a pressure at the outlet side pressure detecting port constitutes an input therefor, a flow rate of driving fluid of said injector constitutes a controlled output therefrom, and means for setting a set point corresponding to saic pressure difference is provided.

Claim 7

A powder flow-rate measuring apparatus comprising a detecting pipe line having an inlet and an outlet, a nozzle for blowing a conveying fluid into said inlet of detecting pipe line, and means for detecting a pressure difference between a pressure at an inlet side pressure detecting port arranged upstream the outlet of said nozzle and a pressure at an outlet sioe pressure oetecting port arranged at said outlet of detecting pipe line, which is characterized by being provided with means tor separating a part of said conveying fluia to feed said inlet side pressure detecting port, means for modulating the pressure in the outlet of detecting pipe line ana/or means for modulating the pressure in the inlet of detecting pipe line, saia means for modulating the pressure in the outlet of aetecting pipe line being an injector consisting of a throat ana a driving nozzle, and an automatic control valve wherein said pressure difference between a pressure at the inlet side pressure detecting port and a pressure at the outlet side pressure detecting port constitutes an input therefor, a flow rate of driving fluid of said injector constitutes a controlled output therefrom, and means for setting a set point corresponding to saic pressure difference is provided.

Claim 8

b. A powder flow-rate measuring apparatus according to Claim 1 wherein said means for introducing a powder into said inlet of detecting pipe line is an approximately vertical pipe line in the fluidized powder bea, the lower end of saia pipe line being the inlet for powaer.

Claim 9

A powaer flow-rate measuring apparatus according to Claim 1 wnerein said means for introducing a powoer into saio inlet of detecting pipe line is an approximately vertical short conduit which communicates witn the fluidized powder bed, tne upper end of said short conduit being the inlet for powder.

Claim 10

A powder flow-rate measuring apparatus according to Claim 1 wherein said means for introducing a powder into said inlet of aetecting pipe line is a powder introducing saide conauit which communicates with the fluidized powuer bed and is provided with a powder arresting member positioned straight over saia inlet of detecting pipe line.

Claim 11

A powder flow-rate Measuring apparatus accoroing to Claim 1 wherein said means tor introcucing a powaer into said inlet of detecting pipe line is a snort conauit which opens downward from said inlet ot detecting pipe line to communicate with the fluidizea powaer bed.