Abstract A gate type blade valve is disclosed which has a fully enclosed blade and is adapted particularly for controlling the flow of dry materials. A curved valve blade is movable in the valve body adjacent the inlet between open and closed positions. The valve housing incorporates an offset portion at one lateral side of the inlet to receive the blade in its open position. The offset fully encloses the blade and prevents loss of material outwardly and prevents contamination inwardly. It also eliminates the necessity for sealing across a blade slot. A wiper seal engages the top of the blade so that the inlet is sealed from the enclosing offset housing portion when the blade is closed. The blade is mounted on a pair of sector-shaped arms which have small frontal areas and offer little resistance to movement through material flowing through the housing. Crank arms are provided by which movement of the blade is controlled and the blade may be moved by power or by a hand lever, or by a remote pull rope connected to the lever. In one embodiment, the housing has a removable cover for access after the valve is installed in the event replacement of the blade is required, or to clean out the valve or obtain a sample of the material. A two-way diverter valve with fully enclosed blades is disclosed in another embodiment.
An enclosed blade valve for handling dry particulate material, comprising a generally rectangular housing having a front wall, a pair of side walls, and a back wall defining a passageway extending from a valve inlet to an outlet, a curved flow control blade movable in said housing adjacent said inlet between said side walls with the concave side thereof facing said outlet, a pair of generally sector-shaped blade supporting arms positioned in said housing adjacent said side walls, said arms presenting a narrow frontal area to offer little resistance to the movement of the blade through said material, means mounting said arms at the apex thereof on said side walls for pivotal movement, means on the wider end of said arms supporting said blade on the concave surface thereof providing for arcuate blade movement between a retracted flow permitting position in which said blade is positioned at one side of said inlet and a flow blocking position in which said blade is extended across said inlet, said back wall being formed with an offset portion and said side walls being extended to join with said back wall to form a space proportioned to receive and enclose said blade in the retracted position thereof, said offset portion having a lower inclined surface in underlying relation to said blade in the retracted position, the slope of said inclined surface being such as to be self-cleaning by gravity of any material which may fall thereon, seaL means at said inlet for sealing said blade with respect to said housing walls in the closed position thereof, and means for moving said blade between its said positions, offset tab means at the forward edge of said blade and tab-engaging retainer means on said arms, said tab and retainer means being engageable by arcuate sliding movement of the blade with respect to said arms providing an attachment free of threaded fasteners for the forward edge of said blade on said arms.
Claim 2
Dependent Claim
325 words
An enclosed blade valve for handling dry particulate material, comprising a generally rectangular housing having a front wall, a pair of side walls, and a back wall defining a passageway extending from a valve inlet to an outlet, a curved flow control blade movable in said housing adjacent said inlet between said side walls with the concave side thereof facing said outlet, a pair of generally sector-shaped blade supporting arms positioned in said housing adjacent said side walls, said arms presenting a narrow frontal area to offer little resistance to the movement of the blade through said material, means mounting said arms at the apex thereof on said side walls for pivotal movement, means on the wider end of said arms supporting said blade on the concave surface thereof providing for arcuate blade movement between a retracted flow permitting position in which said blade is positioned at one side of said inlet and a flow blocking position in which said blade is extended across said inlet, said back wall being formed with an offset portion and said side walls being extended to join with said back wall to form a space proportioned to receive and enclose said blade in the retracted position thereof, said offset portion having a lower inclined surface in underlying relation to said blade in the retracted position, the slope of said inclined surface being such as to be self-cleaning by gravity of any material which may fall thereon, seaL means at said inlet for sealing said blade with respect to said housing walls in the closed position thereof, and means for moving said blade between its said positions, offset tab means at the forward edge of said blade and tab-engaging retainer means on said arms, said tab and retainer means being engageable by arcuate sliding movement of the blade with respect to said arms providing an attachment free of threaded fasteners for the forward edge of said blade on said arms.