US3915077A — Bag forming apparatus

Claim 1

Independent Claim 318 words

Apparatus for forming flattened plastic tubular stock material having inwardly folded gusseted panels along the opposite longitudinal edges thereof into bags having a reinforced flat bottom panel defined by heat sealed seams which comprises, means for supporting a supply roll of said flattened stock material, a base having a generally flat supporting surface over which the leading end of said flattened tube is adapted to be advanced from said supply roll, a heat sealing mechanism movable vertically toward and away from said support surface for forming adjacent the leading end of the flattened tube a straight transverse heat sealed seam and two diagonal heat sealed seams extending inwardly from opposite side edges of the stock material to said straight seal, a guide and feed mechanism on said base which includes a pair of laterally inwardly extending guides on said base, the lateral inner longitudinal edges of said guides being spaced apart transversely and adapted to engage the center fold of each gusseted panel as the stock material is advanced on said support surface to maintain the flattened tube in proper alignment with the heat sealing mechanism, a mechanism for severing said stock material along a line spaced adjacent and forwardly beyond said straight transversely extending seam, said guide and feed mechanism also including a longitudinally reciprocable slide on said base having a portion disposed within each of said gusseted panels and adapted to engage said straight seam to advance the flattened tubular stock and means for operating the apparatus to first lower said heat sealing mechanism to engage the stock on said support surface and thereby form said heat sealed seams, sever the stock along said line adjacent and forwardly of said straight transverse seam, then raise the heat sealing mechanism and thereafter displace the slide forwardly to engage said straight transverse seam and advance the stock so that the leading end thereof is accessible for manual grasping.

Claim 2

Dependent Claim 318 words

Apparatus for forming flattened plastic tubular stock material having inwardly folded gusseted panels along the opposite longitudinal edges thereof into bags having a reinforced flat bottom panel defined by heat sealed seams which comprises, means for supporting a supply roll of said flattened stock material, a base having a generally flat supporting surface over which the leading end of said flattened tube is adapted to be advanced from said supply roll, a heat sealing mechanism movable vertically toward and away from said support surface for forming adjacent the leading end of the flattened tube a straight transverse heat sealed seam and two diagonal heat sealed seams extending inwardly from opposite side edges of the stock material to said straight seal, a guide and feed mechanism on said base which includes a pair of laterally inwardly extending guides on said base, the lateral inner longitudinal edges of said guides being spaced apart transversely and adapted to engage the center fold of each gusseted panel as the stock material is advanced on said support surface to maintain the flattened tube in proper alignment with the heat sealing mechanism, a mechanism for severing said stock material along a line spaced adjacent and forwardly beyond said straight transversely extending seam, said guide and feed mechanism also including a longitudinally reciprocable slide on said base having a portion disposed within each of said gusseted panels and adapted to engage said straight seam to advance the flattened tubular stock and means for operating the apparatus to first lower said heat sealing mechanism to engage the stock on said support surface and thereby form said heat sealed seams, sever the stock along said line adjacent and forwardly of said straight transverse seam, then raise the heat sealing mechanism and thereafter displace the slide forwardly to engage said straight transverse seam and advance the stock so that the leading end thereof is accessible for manual grasping.

Claim 3

Dependent Claim 57 words

Apparatus as called for in claim 1 including a separator film of material to which the plastic tube material does not firmly adhere when subjected to heat and pressure and means supporting said separator film between the folded layers of the gusseted panels in vertical alignment with the mechanism for forming said two diagonal heat sealed seams.

Claim 4

Dependent Claim 30 words

Apparatus as called for in claim 2 including means on said slide directly adjacent said separator film for engaging said film and stripping it from the heat sealed diagonal seams.

Claim 5

Dependent Claim 61 words

Apparatus as called for in claim 2 including a frame mounted on said base, said heat sealing mechanism being mounted on said frame and comprising a heat sealing bar extending transversely straight across the forward end portion of the frame and a pair of heat sealing bars extending diagonally rearwardly from said transverse heat sealing bar in a laterally outward direction.

Claim 6

Dependent Claim 74 words

Apparatus as called for in claim 4 wherein said frame is mounted on said base for vertical movement toward and away from said support surface and including a knife bar on said frame spaced forwardly of said transverse heat sealing bar and cooperating with a shear bar at the forward end of said base for severing the stock material along a line spaced forwardly of said straight transverse seam when said frame is lowered.

Claim 7

Dependent Claim 106 words

Apparatus as called for in claim 4 wherein said slide includes a pair of laterally spaced stripper plates and a pair of laterally spaced pusher feet which are spaced from and forwardly of said stripper plates, the forward edges of the stripper plates extending generally diagonally of said support surface and the forward edges of said pusher feet extending transversely straight across said support surface, said forward edges of the stripper plates and the pusher feet being disposed rearwardly of said diagonally extending and said transverse heat sealing bars, respectively, when the slide is retracted and forwardly of said respective bars when the slide is advanced.

Claim 8

Dependent Claim 95 words

Apparatus as called for in claim 6 wherein said forward edges of the pusher feet are located rearwardly of said transverse heat sealing bar a greater distance than the forward edges of the stripper plates are located rearwardly of said diagonally extending heat sealing bars in the retracted position of the slide so that the forward edges of the stripper plates engage said separator film at the diagonal heat sealed seams before the forward edges of the pusher feet engage the transverse heat sealed seam when the slide is displaced forwardly from its retracted position.

Claim 9

Dependent Claim 25 words

Apparatus as called for in claim 7 wherein the forward edges of the stripper plates are skewed relative to the diagonally extending heat sealing bars.

Claim 10

Dependent Claim 30 words

Apparatus as called for in claim 8 wherein said forward edges of the stripper plates are angularly inclined toward the diagonally extending heat sealing bars in a laterally outward direction.

Claim 11

Dependent Claim 55 words

Apparatus as called for in claim 1 wherein said guides comprise a pair of laterally spaced plates fixed on said base and said longitudinal slide includes a pair of laterally spaced stripper plates and a pair of laterally spaced pusher feet, said stripper plates being slidably disposed between said support surface and said guide plates.

Claim 12

Dependent Claim 50 words

Apparatus as called for in claim 10 wherein said guide plates have forward edges disposed rearwardly of said diagonally extending heat sealing bars and including flexible separator strips mounted on said guide plates and extending forwardly beyond said stripper plates so as to underlie said diagonally extending heat sealing bars.

Claim 13

Dependent Claim 21 words

Apparatus as called for in claim 11 wherein said separator strips are secured to the top face of said stripper plates.

Claim 14

Dependent Claim 90 words

Apparatus as called for in claim 1 including a support frame on which said sealing mechanism is mounted, said support frame being mounted for vertical movement toward and away from said base, a plurality of rotatable cams on said support frame, means for rotating said cams simultaneously, said base having a cam follower fixed thereon and cooperating with one of said cams to raise and lower said support frame, said slide having a cam follower thereon cooperating with another of said cams to reciprocate said slide longitudinally on said base.

Claim 15

Dependent Claim 43 words

Apparatus as called for in claim 13 wherein said two cams are inter-related such that when said support frame is raised said slide is reciprocated forwardly from a retracted to an advanced position and then rearwardly from said advanced to said retracted position.

Claim 16

Dependent Claim 39 words

Apparatus as called for in claim 14 wherein said slide is spring-biased in a forward direction and said last-mentioned cam cooperates with the cam follower on the slide to drive the slide rearwardly against the bias of the spring.

Claim 17

Dependent Claim 72 words

Apparatus as called for in claim 14 including a third cam on said support frame cooperating with a pressure roller on said base which is spring biased in a downward direction, said first and third cams being inter-related such that the pressure roller engages the third cam to bias the support frame in a downward direction when the first cam and its associated cam follower permits the support frame to move downwardly.

Claim 18

Dependent Claim 55 words

Apparatus as called for in claim 14 wherein said means for rotating said cams comprises an electric motor, switch means for de-energizing said motor and means on one of said cams for actuating said switch means when the support frame is in the raised position and said slide has been reciprocated to the retracted position.

Claim 19

Dependent Claim 313 words

Apparatus for forming flattened plastic tubular stock material having inwardly folded gusseted panels along the opposite longitudinal edges thereof into bags having a heat sealed seam at the bottom thereof which comprises, means for supporting a supply roll of said flattened stock material, a base having a generally flat support surface over which the leading end of the flattened tube is adapted to be advanced from the supply roll, a heat sealing mechanism positiOned adjacent the leading end of said base for forming adjacent the leading end of the flattened tube a heat sealed seam which extends transversely across the tube, a guide and feed mechanism on said base which includes a pair of laterally inwardly extending guides on said base, the lateral inner longitudinal edges of said guides being spaced apart transversely and adapted to engage the center fold of each gusseted panel as the stock material is advanced on said support surface to maintain the flattened tube in proper alignment with the heat sealing mechanism, means positioned forwardly beyond said heat sealing mechanism for severing the stock material along a line spaced adjacent and forwardly beyond said transverse seam, said guide and feed mechanism also including a longitudinally reciprocable slide on said base having a portion disposed within each of said gusseted panels and adapted when advanced to engage said transverse seam and thereby advance the flattened tubular stock, and means for operating said apparatus to first cause the heat sealing mechanism to engage the stock and thereby form said transversely extending heat sealed seam, sever the stock along said line adjacent and forwardly of said transverse seam, and thereafter displace said slide forwardly from a position rearwardly of said heat sealing mechanism to engage said transverse seam and advance the stock so that the leading end thereof is disposed forwardly beyond said severing means and is accessible for manual grasping.

Claim 20

Dependent Claim 313 words

Apparatus for forming flattened plastic tubular stock material having inwardly folded gusseted panels along the opposite longitudinal edges thereof into bags having a heat sealed seam at the bottom thereof which comprises, means for supporting a supply roll of said flattened stock material, a base having a generally flat support surface over which the leading end of the flattened tube is adapted to be advanced from the supply roll, a heat sealing mechanism positiOned adjacent the leading end of said base for forming adjacent the leading end of the flattened tube a heat sealed seam which extends transversely across the tube, a guide and feed mechanism on said base which includes a pair of laterally inwardly extending guides on said base, the lateral inner longitudinal edges of said guides being spaced apart transversely and adapted to engage the center fold of each gusseted panel as the stock material is advanced on said support surface to maintain the flattened tube in proper alignment with the heat sealing mechanism, means positioned forwardly beyond said heat sealing mechanism for severing the stock material along a line spaced adjacent and forwardly beyond said transverse seam, said guide and feed mechanism also including a longitudinally reciprocable slide on said base having a portion disposed within each of said gusseted panels and adapted when advanced to engage said transverse seam and thereby advance the flattened tubular stock, and means for operating said apparatus to first cause the heat sealing mechanism to engage the stock and thereby form said transversely extending heat sealed seam, sever the stock along said line adjacent and forwardly of said transverse seam, and thereafter displace said slide forwardly from a position rearwardly of said heat sealing mechanism to engage said transverse seam and advance the stock so that the leading end thereof is disposed forwardly beyond said severing means and is accessible for manual grasping.

Claim 21

Dependent Claim 15 words

The combination set forth in claim 18 wherein said guides are mounted on said slide.

Claim 22

Dependent Claim 27 words

The combination set forth in claim 19 wherein the portion of said reciprocable slide adapted to engage said transverse seam comprises the forward edges of said guides.

Annuity Stage	Window Opens	Payment Deadline	Surcharge Period Until	Estimated Fee	Status
3.5 Years (Year 4)	1978-10-27	1979-04-28	1979-10-28	$2000.00	Window Closed / Lapsed
7.5 Years (Year 8)	1982-10-27	1983-04-28	1983-10-28	$3760.00	Window Closed / Lapsed
11.5 Years (Year 12)	1986-10-27	1987-04-28	1987-10-28	$7700.00	Window Closed / Lapsed

Bag forming apparatus

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