Machines for applying bags or sacks to the discharge spouts of bag-filling machines

Claim 2

In a machine for applying a bag to the discharge spout of a bag filling machine, including a transfer device for advancing the bag to the discharge spout, said transfer device comprising opposed suction means for engaging opposite sides of the bag adjacent its mouth, and means for parting said opposed suction means so as to open the bag mouth for placing over the discharge spout, improved suction means comprising: (a) opposed main suction members arranged to engage the bag adjacent one end of its mouth and pivotally mounted so as to be rockable apart to open said bag mouth, (b) opposed auxiliary suction members pivotally mounted coaxially with the pivot axes of said main suction members and arranged to engage said bag adjacent its mouth at positions spaced from said main suction members, said auxiliary suction members being rockable apart together with said main suction members to assist opening of said bag mouth.

Claim 3

A machine as claimed in claim 1, wherein said auxiliary suction members are pivoted on arms which are pivotally mounted coaxially with said main suction members, and coupling means connects said main suction members to said arms so that said arms are rocked in response to rocking movement of said main suction members.

Claim 4

A machine as claimed in claim 1, wherein said main and auxiliary suction members are rockable by two fluid-operated cylinder and piston units mounted side-by-side and having their piston rods inter-connected by a yoke member, said yoke member being pivoted to said piston rods and being connected to crank arms secured to the pivots of said suction members by means which is attached to said yoke member intermediate its ends, whereby said suction members can be rocked together, or fully apart, or to an intermediate position by selective actuation of said cylinder and piston units.

Claim 5

A machine as claimed in claim 1, wherein said transfer device includes a swinging arm which mounts said main and auxiliary suction members and is at least partially hollow and serves as ducting for connecting said suction members to a source of suction.

Claim 6

A machine as claimed in claim 4, wherein said swinging arm is rocked about its swing axis by fluid-operated means, whereby the swinging arm is movable between predetermined stations during each transfer cycle, in which stations the bag is engaged by said suction members, the bag mouth is opened preparatory to placing over the discharge spout, the bag is placed over said discharge spout and released, and said swinging arm is stopped after its return stroke, and prior to commencing the next transfer cycle.

Claim 7

A machine as claimed in claim 1, wherein a suction pick-up device is adapted to lift the bag from a stack of flat bags and turn the bag from a horizontal position into a substantially vertical position, with its mouth disposed along one vertical side edge of the bag, and said transfer device is arranged to engage the bag, held by said pick-up device in a substantially vertical position, and advance said bag to said discharge spout, and wherein said suction pick-up device is reciprocable substantially vertically for lifting the bag from the stack, and includes suction means for gripping said bag which is rockable about a substantially horizontal axis so as to turn the bag into said substantially vertical position preparatory to engagement by said transfer device.

Claim 8

A machine as claimed in claim 6, wherein said pick-up device is reciprocable along a path disposed to one side of the vertical plane of movement of said transfer device and said pick-up suction means is arranged to turn the bag substantially into said plane of movement, of the transfer device, when it turns said bag into said substantially vertical position, so as to permit the bag to be engaged by said transfer device.

Claim 9

A machine for applying a bag to the discharge spout of a bag filling machine comprising in combination: (a) a suction pick-up device adapted to lift the bag from a stack of flat bags and turn said bag from a horizontal position into a substantially vertical position, with its mouth disposed along one vertical side edge of said bag, (b) said suction pick-up device comprising a suction box and pick-up suction members for gripping said bag pivotally mounted on said suction box for rocking movement about a substantially horizontal axis, whereby said suction members are rockable to turn said bag gripped thereby into said substantially vertical position, (c) fluid-operated means operatively connected to said suction box for reciprocating said suction box in a substantially vertical direction for lifting said bag from said stack, (d) at least one hollow guide rod for guiding said suction box for vertical reciprocating movement, (e) said at least one hollow guide rod also comprising means via which suction is applied to said suction box and, hence, said pick-up suction members, and (f) a suction transfer device arranged to engage said bag, held by said pick-up device in said substantially vertical position, advance said bag from said pick-up device into a substantially upright position, in which its mouth is uppermost, and open said bag mouth for placing over said discharge spout.

Claim 10

A machine for applying a bag to the discharge spout of a bag filling machine comprising in combination: (a) a suction pick-up device adapted to lift the bag from a stack of flat bags and turn said bag from a horizontal position into a substantially vertical position, with its mouth disposed along one vertical side edge of said bag, (b) said suction pick-up device comprising a suction box and pick-up suction members for gripping said bag pivotally mounted on said suction box for rocking movement about a substantially horizontal axis, whereby said suction members are rockable to turn said bag gripped thereby into said substantially vertical position, (c) fluid-operated means operatively connected to said suction box for reciprocating said suction box in a substantially vertical direction for lifting said bag from said stack, (d) at least one hollow guide rod for guiding said suction box for vertical reciprocating movement, (e) said at least one hollow guide rod also comprising means via which suction is applied to said suction box and, hence, said pick-up suction members, and (f) a suction transfer device arranged to engage said bag, held by said pick-up device in said substantially vertical position, advance said bag from said pick-up device into a substantially upright position, in which its mouth is uppermost, and open said bag mouth for placing over said discharge spout.

Claim 11

A machine as claimed in claim 8, wherein the or each hollow guide rod is slidably mounted at its upper end in a suction tank which is connectable to a source of suction, and said pick-up suction members are connected to said suction tank via said pick-up box and said hollow guide rod(s).

Claim 12

A machine as claimed in claim 8, wherein said suction box is vertically reciprocable along a path disposed to one side of the vertical plane of movement of said transfer device, and said pick-up suction members are arranged to turn said bag substantially into said plane of movement of said transfer device, when it turns said bag into said substantially vertical position, so as to permit said bag to be engaged by said transfer device.

Claim 13

A machine for applying a bag to the discharge spout of a bag filling machine, comprising: (1) a suction pick-up device adapted to lift a bag from a stack of flat bags and turn the bag from a horizontal position into a substantially vertical position, with its mouth disposed along one vertical side edge of the bag, said pick-up device including (a) suction means for gripping said bag pivoted for rocking movement about a substantially horizontal axis, (b) first actuating means for reciprocating said pivoted suction means along a substantially vertical path for lifting the bag from said stack, (c) second actuating means for rocking said suction means about said horizontal pivot axis to turn the bag lifted by said suction means into said substantially vertical position; (2) a suction transfer device arranged to engage the bag, held by said pick-up device in a substantially vertical position, and transfer it into a substantially upright position with its mouth open and uppermost for placing over the discharge spout of a filling machine; (3) means mounting said transfer device for swinging movement about a substantially horizontal axis substantially perpendicular to said pivot axis of said pick-up suction means; (4) third actuating means for swinging said transfer device to transfer the bag from said pick-up device into said substantially upright position; (5) said suction transfer device including (a) opposed suction fingers arranged to engage the bag held by the pick-up device adjacent the upper end of its mouth and pivotally mounted so as to be rockable apart, (b) opposed auxiliary suction members rockably mounted on arms pivotally mounted coaxially with said suction fingers and arranged to engage the bag adjacent the lower end of its mouth; (6) fourth actuating means for rocking said suction fingers and said auxiliary suction members apart upon swinging of the bag into said upright position, whereby to open the bag mouth preparatory to placing over the discharge spout; (7) a blower unit connected to apply suction to said pick-up suction means, suction fingers and auxiliary suction members; (8) control means for controlling said actuating means and said application of suction to cause the bag to be successively moved by said pick-up and transfer devices from said stack to said upright position.

Claim 14

A machine for applying a bag to the discharge spout of a bag filling machine, comprising: (1) a suction pick-up device adapted to lift a bag from a stack of flat bags and turn the bag from a horizontal position into a substantially vertical position, with its mouth disposed along one vertical side edge of the bag, said pick-up device including (a) suction means for gripping said bag pivoted for rocking movement about a substantially horizontal axis, (b) first actuating means for reciprocating said pivoted suction means along a substantially vertical path for lifting the bag from said stack, (c) second actuating means for rocking said suction means about said horizontal pivot axis to turn the bag lifted by said suction means into said substantially vertical position; (2) a suction transfer device arranged to engage the bag, held by said pick-up device in a substantially vertical position, and transfer it into a substantially upright position with its mouth open and uppermost for placing over the discharge spout of a filling machine; (3) means mounting said transfer device for swinging movement about a substantially horizontal axis substantially perpendicular to said pivot axis of said pick-up suction means; (4) third actuating means for swinging said transfer device to transfer the bag from said pick-up device into said substantially upright position; (5) said suction transfer device including (a) opposed suction fingers arranged to engage the bag held by the pick-up device adjacent the upper end of its mouth and pivotally mounted so as to be rockable apart, (b) opposed auxiliary suction members rockably mounted on arms pivotally mounted coaxially with said suction fingers and arranged to engage the bag adjacent the lower end of its mouth; (6) fourth actuating means for rocking said suction fingers and said auxiliary suction members apart upon swinging of the bag into said upright position, whereby to open the bag mouth preparatory to placing over the discharge spout; (7) a blower unit connected to apply suction to said pick-up suction means, suction fingers and auxiliary suction members; (8) control means for controlling said actuating means and said application of suction to cause the bag to be successively moved by said pick-up and transfer devices from said stack to said upright position.