Patent GB-779376-A (GB)
Title: Machine for producing bed springs
IPC: B21F33/04
Filed: 1955-03-01
Abstract: 779,376. Connecting mattress springs. SPRING MACHINERY CO. March 1, 1955 [Jan. 3, 1955], No. 6065/55. Class 83 (4). [Also in Group XIV] A machine for making bed springs and having means to move and hold two rows of spring coils in position to be connected by helical connectors and including pivoted foldable members that assume a straightened position to lock said means in spring coil holding position, comprises in combination, an electric circuit including switch means closed by said foldable members when straightened, a cycle timer having an operating motor energized upon closing of said circuit, said timer being provided with a series of operating cams driven by said motor and a series of circuitclosing switches each controlled by the respective cams, and helix-forming, feeding and cutting devices controlled by the circuits closed by the latter switches. Adjacent rows of coil springs 16 to be connected by upper and lower helcial connectors 17 are held together by bars 40, 41 moved by shafts 57. A cam lug 58, Fig. 4 (not shown), on one of the shafts 57 then closes a switch to cause pneumatic cylinders 55 to straighten toggles 44, 45 to lock the bars 40, 41 in their coil-holding position. Straightening of the toggles closes further switches 56, Fig. 4 (not shown), to actuate a cycle timer, to turn a cam-shaft 71, Fig. 4 (not shown), one revolution. The cams operate switches to actuate, in succession, helix-forming and feeding means 11, 12, Fig. 1, helix-endcutting units 25, 26, 27, 28, toggle-release means, and helix-end-bending units. The helices 17 are fed through troughs 24, the lids of which are lifted, if the feed of the helix is obstructed, to open a switch to stop the helixforming and feeding means. Such means are also stopped by a switch operated by the helix end after the helix has passed through and connected adjacent rows of springs. A switch opened by a completed bed-spring or by counting mechanism stops the helix feed during one cycle of operations thus separating a completed bed spring from the first row of the next spring being built up. The machine is adapted for manual actuation. The cutters and twisters may be mechanically interlocked. Coil feed, holding and ejecting means, Figs. 5, 8. Two adjacent rows of coils 16 compressed tightly between upper and lower guides 211, 212, are engaged by pushers 213, 214, operated by cams through toggle means 219, 220, and moved over shims 234 on the guides to a position, Fig. 8, where the end convolutions 233 of one row overlap the end convolutions of the other row above grooves 229 in the guides. At the same time ejector means 261, engaging coils secured by a helical connector 17 to those of a previous row, operated through lostmotion means 210 from the pusher 214, move the secured coils to the right. Stops 259 halt the movement of the means 261 just before the completion of the movement of the pusher 214 so that the required overlap is produced. The helical connectors 17 are fed through the grooves 229 when the overlapping end convolutions are locked between the pushers 213, 214 and opposed holding means 215, 216 moved in just before the completion of the movement of the pushers 213, 214. Shearing means, Figs. 9, 13. For cutting the ends of the helical connectors 17 after connecting the coils, cutter units are provided, each of which comprises a fixed blade 341 and pivoted thereto at 337 a co-operating blade 345 operated by a follower 354, moved by a fluid-actuated slide 349, engaging a cam-slot 346 in the blade so as to give the blade first, a rapid approach movement, then a slowcutting stroke. A helix guide 312 is adjustably secured to the fixed blade 341. The fixed blade 341 is adjustably carried by a yoke 326 pivoted at 330 and swung to carry the blades out of the path of the severed helix by a follower 355 on the side of the slide 349 engaging a cam-slot 359 in the yoke 326. Helix-end bending, Figs. 15, 18. Means for bending the ends of the helical connectors 17, each comprise a bending head 412, having a pin 435 and a grooved eccentric wall upstanding therefrom. The head 412 is carried by a shaft 425 in a sleeve 436 lifted by fluid pressure means 414. A pin 430 on the shaft 425 engages a helical slot 441 in the sleeve 436 and a pin 429 on the shaft 425 engages a transverse groove 423 in a fixed frame 410, so that as the sleeve 436 is raised the shaft 425 is raised with it until the pin 429 leaves the groove 423 when, further axial movement being prevented by a head 426 on the shaft, the shaft is rotated, to cause the head 412 to effect the bending. Specification 742,039 is referred to.