Patent GB-1443066-A (GB)
Title: Ultrasonic pattern welding apparatus
IPC: B29C65/78
Filed: 1973-07-23
Abstract: 1443066 Seaming non-metallic sheet material; laminates CROMPTON & KNOWLES CORP 23 July 1973 [15 Sept 1972] 35004/73 Headings B5K and B5N Apparatus for ultrasonically welding at least two thermoplastic sheets comprises at least one ultrasonic welding member 38 to be disposed on one side of the sheets, means 48, 50 to advance the sheets relative to the member 38, an anvil holder 22 to be located on the other side of the sheets, a plurality of spaced anvils 32 supported by the holder 22 and control means for selectively moving the anvils 32 to produce a plurality of welds in the sheets in a pattern. In one embodiment, Figs. 1, 3, 4 and 5, the holder 22 is located between end portions 20 of a slidable base 16 and is supported by brackets 23 freely slidable on rods 24 and held by threaded collars 44, Fig. 3. The holder 22 is adjustable vertically relative to the member 38 by turning the collars 44. Spherical anvils 32 are held in cavities 26, Fig. 4, in the holder 22 and are individually raisable into operative position by the supply of compressed air through a conduit 36 into an opening 34 in each cavity 26. Springs (not shown) may be provided to assist the downward return movement of the anvils 32. The sheets to be welded are fed over a guide roll 46, Fig. 1, and pass between the member 38 and the holder 22 and are taken up by rollers 48, 50, the roll 50 being intermittently driven from a crank 52 driven from a motor 66. Alternatively, the roll 50 may be driven continuously through a pulley and belt drive. The rods 24 are reciprocated vertically by eccentrics 68 driven from the motor 66. This motion is synchronized with the intermittent rotation of the roll 50 so that the holder 22 is raised when the sheets are stationary. The holder 22 is reciprocated along an axis parallel to the working surface 40 of the member 38 by a crank (74), Fig. 2 (not shown), driven from the motor 66 through a right angle drive 82, Fig. 1, which may be a gear reducer so that for each horizontal reciprocation of the holder 22 there may be several vertical reciprocations or a gear increaser so that for each vertical reciprocation there may be several horizontal reciprocations. The movements of the anvils 32 are controlled by projections 88, Fig. 5, on a pattern drum 86 opening air valves 94 to supply compressed air to the conduits 36, one valve 94 being provided for each conduit 36. Zig-zag welds may be produced by driving the roll 50 continuously, disconnecting the drive to the eccentrics 68 and maintaining the rods 24 in the upper position, and maintaining the lateral shifting of the holder 22. In a modification, Fig. 6, elongated anvils 32<SP>1</SP> are slidably supported in holes 102 of the holder 22<SP>1</SP> and are projectable individually into operative position by the engagement of followers 106 thereon with projections 112 on a pattern conveyer 110 or a pattern drum. In a further modification, Fig. 8, cylindrical anvils 32<SP>11</SP> having reduced portions 107 with working surfaces 109 are located in cavities 26<SP>11</SP> in the holder 22<SP>11</SP>.