초록 ▼

A filter leaf includes a continuous, elongated closure member, a first screen welded around its entire periphery to one side of the member, and a second screen welded around its entire periphery to the other side of the member to define a filtrate collection space between the two screens and the mem

A filter leaf includes a continuous, elongated closure member, a first screen welded around its entire periphery to one side of the member, and a second screen welded around its entire periphery to the other side of the member to define a filtrate collection space between the two screens and the member. Means are provided for removing filtrate from the collection space. The filter leaf is made by clamping the closure member and one of the screens between two plates so the screen covers one side of the member and so the outer portions of the member and screen project outwardly from one of the plates. The outwardly projecting portions of the screen and member are irradiated with a laser beam to melt the screen and member to cause them to fuse together. The periphery of the outwardly projecting portions of the member and screen are moved relative to the laser beam while the member and screen are clamped together to form a continuous weld of the screen to the member around the entire periphery of the screen. The foregoing process is then repeated with a screen on the opposite side of the member so that an enclosed filtrate space is formed between the two screens and the interior wall of the member.

대표청구항 ▼

A filter leaf comprising: a closed frame having an inner periphery defining an open space within the frame and an outer periphery, a first flat side surface extending between the peripheries, and a second flat side surface extending between the peripheries; a first screen covering the open space suc

A filter leaf comprising: a closed frame having an inner periphery defining an open space within the frame and an outer periphery, a first flat side surface extending between the peripheries, and a second flat side surface extending between the peripheries; a first screen covering the open space such that the outer periphery of the first screen overlaps and abuts the first side surface of the frame; a first bead made of the same material as the first screen bonding the edge of the first screen to the first side surface of the frame, the first bead having a flange extending into the frame from the edge of the first screen toward the inner periphery of the frame; a second screen covering the open space such that the outer periphery of the second screen overlaps and abuts the second side surface of the frame; and a second bead made of the same material as the second screen bonding the edge of the second screen to the second side surface of the frame the second bead having a flange extending into the frame from the edge of the second screen toward the inner periphery of the frame.