US3741080A

US3741080A - Bag forming and manipulating machine

Info

Publication number: US3741080A
Application number: US00096066A
Authority: US
Inventors: P Kuhnle; F Gaukier; W Gassmann
Original assignee: FR Hesser Maschinenfabrik AG
Current assignee: FR Hesser Maschinenfabrik AG
Priority date: 1970-12-08
Filing date: 1970-12-08
Publication date: 1973-06-26
Anticipated expiration: 1990-06-26
Also published as: CH537300A

Abstract

A bag making and manipulating machine wherein the web is drawn from a supply roll by advancing devices provided on two reciprocable carriages one of which performs a return stroke while the other performs a forward stroke and vice versa. The advancing devices engage and draw the web during forward movements of the respective carriages simultaneously with closing of welding devices which are carried by the carriages. The web is folded prior to reaching the welding devices which provide the thus folded web with transverse seams which are severed by knives downstream of the carriages so that the folded and welded web yields a series of discrete bags. Pairs of such bags are moved sideways to a conveyor which transports two rows of bags lengthwise past several operating stations.

Description

United States Patent 1191 Kuhnle et al.

[ June 26, 1973 BAG FORMING AND MANIPULATING 2,126,453 8/1938 Criley et al. 226/112 ux M ACHINE 3,443,462 5/1969 Doohan 83/158 x [75] Inventors: a g 2 t Primary Examiner-Andrew R. Juhasz rggi fgf g z m Attorney-Michael s. Striker Gassmann, Winnenden, Wurttemberg, all of Germany [57] ABSTRACT A bag making and manipulating machine wherein the [73] Asslgnee' g Hesseghgachmenflabgk web is drawn from a supply roll by advancing devices tuttgart' a annsta ermany provided on two reciprocable carriages one of which [22] Filed: Dec. 8, 1970 performs a return stroke while the other performs a forward stroke and vice versa. The advancing devices en- [21] Appl 96066 gage and draw the web during forward movements of the respective carriages simultaneously .with closing of 5 2] U.S. Cl 93/8 R, 83/240, 83/560, el ng devices which are carried by the carriages. The

93/DIG, 1, 156/583 web is folded prior to reaching the welding devices [51] Int. Cl B3lb 1/64, 826d 5/16 which p i the h fol ed Web with transverse [58] Field of Search 93/8 R, 8 v, DIG. 1; s ams hi h a ever d y knives downstream of the 156/583 carriages so that the folded and welded web yields a series of discrete bags. Pairs of such bags are moved side- [56] References Cited ways to a conveyor which transports two rows of bags UNITED STATES PATENTS lengthwise past several operating stations.

2,944,469 7/1960 Heinzer 93/8 R 18 Claims, 7 Drawing Figures 1? 1411 28 3/ 25 24 2a a; as 199 1 1 1 1 Texan-,2, a T 90 lg 1 5 a wad- .i, V 4 1 BAG FORMING AND MANIPULATING MACHINE BACKGROUND OF THE INVENTION The present invention relates to bag making or forming and manipulating machines in general, and more particularly to improvements in those parts of such machines wherein a web of flexible material is converted into discrete bags or analogous containers and the thus obtained containers are thereupon transported toward one or more processing stations.

It is already known to convert a continuously or intermittently advancing flexible web of heat-scalable material into a succession of bags which are thereupon separated from each other and transported past one or more opening, filling, sealing, cooling, stacking and/or carton-filling stations. As a rule, the web is drawn from a supply roll and is folded by a so-called plow to be converted into a folded web consisting of two strips which are disposed face-to-face and are ready to be provided with transverse seams in order to convert the folded web into a row of coherent bags each open at one side for reception of granular, powdery or other material. The open sides of the bags are thereupon sealed and the bags are introduced into cartons, crates or other receptacles. r

A drawback of presently known bag making and manipulating machines is that the width of bags, as considered in the direction of their travel, fluctuates within a certain range. This is often due to the fact that the web is transported continuously and/or that the web is moved stepwise but through considerable distances so that the heat-sealing device or devices must provide the folded web with two or more seams at a time. Another serious drawback of presently known bag making and manipulating machines is that the bags which are severed from the web invariably form a single file or row which is advanced past several processing stations. Still further, the presently known machines are too long because the bags which are opened, filled,sealed, cooled and/or otherwise treated remain in the general plane of the travelling web. I

SUMMARY OF THE INVENTION. f

An object of the invention is to provide a bag making and manipulating or processing machine which is capable of producing, filling, sealing and/or otherwise treating bags or analogous containers for pulverulent, granular and/or liquid substances (particularly foodstuffs) with a high degree of accuracy, in a small area and at a rate which at least approximates the production rate of presently known machines.

Another object of the invention is to provide the machine with novel and improved web folding, feeding, sealing, severing and bag transporting devices.

A further object of the invention is to provide novel and improved adjusting means which renders it possible to convert the machine for the production of bags of desired length and/or width.

An additional object of the invention is to provide a bag making and manipulating device which can simultaneously fill, seal, cool and/or otherwise manipulate two or more bags to thus simplify the introduction of scaled bags into crates, boxes or analogous receptacles.

Still another object of the invention is to provide the improved machine with novel means for transferring freshly formed bags from the severing station to a conveyor which transports such bags past one or more processing stations.

The improved machine is employed for the production and manipulation of bags or analogous containers and comprises a supply of flexible web consisting at least in part of weldable (heat-scalable) material, feeding means for drawing the web from the supply and for advancing the web lengthwise along a predetermined path, a folding unit located between the supply and the feeding means and serving to convert the web into a folded web having a pair of overlapping face-to-face strips, a forming unit comprising two welding devices movable into and from welding engagement with the folded web downstream of the folding unit to provide the folded web with transverse seams and to thus convert the folded web into a row of interconnected open containers, means for moving one of the welding devices in the direction of travel of the folded web while moving the other welding device counter to such direction'and vice versa, and means for moving that welding device which moves in the direction of web travel into engagement with the folded web so that the two welding devices form one seam at a time, and severing means for separating successive foremost containers from the row.

The machine further comprises a first conveyor which receives freshly separated containers from the severing means and transports groups of such containers in a direction at an angle to the direction of lengthwise movement of the folded web, and a second conveyor which'receives containers from the first conveyor and transports several rows of such containers lengthwise along paths which are parallel to the path of the folded web. The containers which are carried by the second conveyor are moved past several operating or processing stations, particularly container filling, sealing, cooling and stacking stations.

The novel features which are considered as characteristic of the invention are set forth inparticular in the appended claims. The improved machine itself, how- BRIEF DESCRIPTION OF THE DRAWING FIG. 1 isa plan view of a first portion of a bag forming and processing machine which embodies the invention;

FIG. 2 is a plan view of a second portion of the machine;

FIG. 3 is an enlarged fragmentary transverse vertical sectional view as seen in the direction of arrows from the line III-III of FIG. 1;

FIG. 4 is an enlarged fragmentary transverse vertical sectional view as seen in the direction of arrows from the line IV-IV of FIG. 1;

FIG. 5 is a side elevational view of a portion of the structure shown in-FIG. 2;

FIG. 6 is a transverse vertical sectional view substantially as seen in the directionaof arrows from the line VI-VI of FIG. 5; and

FIG. 7 is a fragmentary side elevational view substantially as seen in the direction of arrow VII in FIG. 2.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring first to FIGS. 1 and 2, there is shown a portion of a bag forming and manipulating machine which comprises a folding unit 1 serving to fold a web 160 of flexible material so that the web is converted into a folded web 161 consisting of two overlapping face-toface strips, a bag making or forming unit 2 wherein the strips of the folded web 161 are converted into a row 161a of connected open-ended bags 162, a cutting or severing unit 9 which separates successive foremost bags 162 from the row 161a, a first conveyor 10 which transports the bags 162 sideways, and a second conveyor 11 which accepts bags 162 from the conveyor 10 and transports them lengthwise along several paths each of which is parallel to the path for the folded web 161 and row 161a. The conveyor 11 transports the bags 162 past a series of operating or processing stations where the bags are filled, their open ends sealed, the thus sealed ends cooled, and the resulting filled bags stacked in boxes or the like.

The web folding unit 1 includes a so-called folding or forming plow which comprises two mutually inclined folding plates l2, 13 located at a level above the web 160 which is being drawn from a supply roll 1160. The folding unit 1 further includes two pairs of vertical pressing bars 14 which are mounted in the frame 18 or on the base of the packaging machine downstream of the tip of the folding plow and complete the conversion of the web 160 into two overlapping face-to-face strips. The angle between the folding plates 12, 13 is preferably variable by an adjusting device including two feed screws 15, 16 and a nut 17 which meshes with the feed screws. The illustrated adjusting device is a functional equivalent of a conventional turnbuckle. The plow including the folding plates 12, 13 is movable up and down in a manner known from the art of bag making machines to insure that the upper edges of the strips of the folded web 161 are located in a predetermined plane regardless of the width of the web 160, i.e., even if the web 160 shown in FIG. 1 is replaced with a wider or narrower web. In contrast to the construction of presently known machines, the pressing 'bars 14 are preferably mounted on the base or in the frame 18 of the machine so that they need not share the vertical movements of the folding plow. The width of the web 160 determines the length or height of the bags 162.

The bag making or forming unit 2 includes two carriages 3, 4 which are reciprocable along parallel horizontal guides here shown as tie rods 19 fixedly mounted in the frame 18 of the machine. The carriages 3, 4 are movable with and relative to each other and each thereof supports a web feeding or advancing device or tongs 5 and a sealing or welding device 6. The carriage 3 is reciprocable in response to rotation of a cam 20 which is mounted on a horizontal camshaft 22 driven by the output shaft or a prime mover 21. The prime mover 21 is an electric motor which drives the camshaft 22 by way ofa reducing gearing 21a. The motion transmitting connection between the cam 20 and the carriage 3 includes a link train having a roller follower 23 which extends into an endless groove in the lefthand face of the cam 20 and is rotatably mounted on a lever 24 which is fixed to a horizontal shaft 24a. The lever 24 is articulately connected with a rod 25 which can pivot a bell crank 26 pivotable in the housing 18 about a vertical axis and articulately connected to the carriage 3 by way of a further rod 27.

The carriage 4 is reciprocable by a second cam 28 which is also secured to the camshaft 22. The motion transmitting connection between the cam 28 and the carriage 4 includes a roller follower 29 extending into an endless groove in the right-hand face of the cam 28 and mounted on a lever 30. The latter is rockable about the axis of the shaft 24a and is articulately connected with a rod 31 which can pivot a two-armed lever 32 mounted on a vertical pin in the housing 18. One arm of the lever 32 is coupled to a link 33 which can rock a bell crank 34. The latter is articulately coupled to the carriage 4 by means of a further rod 35. The configuration of the grooves in the

earns

20, 28 is such that the carriages 3, 4 can move simultaneously toward and away from each other as well as that the carriages can simultaneously dwell in predetermined end positions for preselected intervals of time.

Each of the

bell cranks

26, 34 comprises an arm 36 which includes two relatively

movable sections

37, 38 to allow for changes in the effective length of the arm 36 in order to change the extent of movement of the carriage 3 or 4 along the tie rods 19. In this way, the op erator can determine the width of the bags 162, namely that dimension which is parallel to the path for the folded web 161.

The carriages 3, 4 are respectively connectable with

toothed racks

39, 40 which are adjustable lengthwise of the tie rods 19. The rods 27, are respectively connected to the

racks

39, 40. The means for adjusting the racks 39, comprises shafts 41 which can be rotated by suitable tools and carry pinions 42 meshing with the respective racks. This is best shown in FIG. 3.

The web feeding or advancing device 5 on the carriage 3 is identical with the advancing device on the carriage 4. Each of these advancing devices comprises a first jaw 43 which is rigid with the respective carriage (see the carriage 3 in FIG. 3) and is provided with an elastic lining 44 of friction generating material, and a second or complementary jaw 45 which is movable toward and away from the fixedly mounted jaw 43. The

jaws

43, 45 are located atthe opposite sides of the path for the folded web 161. The movable jaw 45 is mounted on aholder 46 articulately connected with two levers 47, 48 which are pivotably mounted in the carriage 3 (see FIG. 3). This carriage further supports a pivotable lever 49 one arm of which is coupled to the ever 47 by way of the lever 48 and a link 50. The other arm of the lever 49 carries a roller follower 51 and is connected with a helical spring 52 mounted in the carriage 3. The frame 18 supports pivotable levers 53, 54 coupled to each other by a link 55 which carries a guide rail 56 for the roller follower 51 on the lever 49. The guide rail 56 is located at a level above the roller follower 51. The lever 53 is pivotable by a rod 57' which is movable up and down by a cam, not shown, mounted in the frame 18. When the just mentioned cam causes the rod 57 to move upwardly, the guide rail 56 causes the roller follower 51 to pivot the lever 49 in a counterclockwise direction, as viewed in FIG. 3, to stress the spring 52. Such pivotal movement of the lever 49 causes the link to pivot the lever 47 in a direction to move the jaw 45 away from the fixedly mounted jaw 43 of the advancing device 5. When the rod 57 is permitted to move downwardly, the spring 52 is free to contract and the jaw 45 is caused to move against the folded web 161 to press the web against the elastic lining 44 of the jaw 43.

The sealing device 6 for one of the carriages, 3, 4 is illustrated in FIG. 4. This device comprises two electrically heated sealing or welding bars 58, 58a. The bar 58 is fixedly mounted on a holder 59 and the bar 58a is movably supported by a second holder 60. Helical springs 61 react against the holder 60 and bias the bar 58a in a direction toward the fixedly mounted bar 58. Each of the

holders

59, 60 is articulately connected to a pair of

levers

62, 63 which are pivotable on

pins

64, 65 provided therefor on the respective carriage 3 or 4. The levers 62 have arms 66 which extend downwardly beyond the respective pivot pins 64 and carry roller followers 67 serving to track a cam 68 which is pivotably mounted in the respective carriage. A spring 69 serves to bias the roller followers 67 against the face of the cam 68. The latter is mounted on a shaft 70 which is connected to a lever 71 having a bifurcated arm whose prongs straddle a control rail 72 extending in parallelism with the tie rods 19. The control rail 72 is carried by levers (not shown) which are mounted on the shaft 70 or on a separate shaft which is coaxial with the shaft 70. The means for moving the control rail 72 back and forth alongan arc whose center of curvature is on the axis of the shaft 70 comprises pneumatic cylinder 73 whose piston rodis connected with

levers

75, 76 pivotable on a pin 74. The lever 76 is articulately connected with the rail 72 by means of two rods 77. The

levers

75, 76 are rigidly connected to each other. When the piston rod of the cylinder 73 causes the control rail 72 to move along the aforementioned arcuate path, the rail '72 changes the angular position of the cam 68 whereby the roller followers 67 cause the sealing bars 58, 58a to move toward or away from each other. Such bars serve to provide the folded web 161 with longitudinally spaced transverse vertical seams to thus convert the web 161 into a row 161a of interconnected bags 162.

The cylinder 73 can be connected with a supply conduit 79 for compressed fluid by way of an electromagnetical-ly operated regulating valve 78 whose circuit includes an adjustable timer 80 and a master switch 81. The latter is closed by a trip of the drive of the machine. The timer 80 is set'in such a way that the longest interval during which the cylinder 73 can move the control rail 72 at most equals the combined length of two intervals of movement and one interval of dwell of the web 161 when the machine is operated at a maximum speed. The timer 80 enables the operator to select the length of that interval during which the sealing bars 58, 58a engage the adjacent portions of the folded web 161 in dependency on or independently of the operating speed of the machine, and to maintain such interval at a selected constant value. The structure shown in FIG. 4 constitutes an actuating means for moving the illustrated welding device 6 into engagement with the folded web 161 while the respective carriage 3 or 4 travels in the direction of lengthwise travel of the web.

The feed rolls 7, 8 are biased against each other with a variable force. The drive for these feed rolls is designed in such a way that their peripheral speed slightly exceeds (by a few percent) the speed of forward movement of the carriage 3 or 4. In the illustrated embodiment, the drive for the feed rolls 7, 8 derives motion from the earns and 28 for the carriages 3 and 4. As mentioned above, the

cams

20, 28 transmit motion to bell cranks 26, 34 and the arms 82 (see FIG. 1) of these bell cranks are articulately connected to rods 83, 84 I which transmit motion to further rods 86 by way of bell cranks 85. The rods 86 are connected with two gear segments 87 which are disposed at different levels and have teeth 88. Each segment 87 meshes with a discrete gear 89, and each of these gears is mounted on a shaft 90 by way of a one-way clutch, not shown. The shaft 90 carries a sprocket wheel 91 for a chain 92 which drives a second sprocket wheel 93 (FIG. 2) rigid with the feed roll 7. If desired, the feed roll 8 can be positively driven by the feed roll 7 through the intermediary of a pair of mating gears, not shown.

The cutting or severing unit 9 is shown in FIGS. 2 and 5. It comprises a holder which is adjustable along two guide rails 94 extending in parallelism with the tie rods 19 for the carriages 3 and 4. The holder 95 supports a fixedly mounted knife 96 and a movable knife 98 mounted on two pivotable arms 97. The means for adjusting the holder 95 with reference to the guide rails 94 comprises a feed screw 99.

The drive for the movable knife 98 comprises a rotary cam 100 mounted on a camshaft 104, a shaft 103 which is connected with the arms 97, and a lever 102 which is rigid with the shaft 103 and is provided with a roller follower 101 which tracks the face of the cam 100. Means (not shown) is provided to bias the roller follower against the cam 100. The latter is adjustable lengthwise of the camshaft 104. The cam 100 moves the knife 98 with reference to the knife 96 while the' carriages 3, 4 are at a standstill. The extent of adjustment of the cam 100 on the camshaft 104 is proportional to the extent of adjustment of the holder 95 by means of the feed screw 99. This feed screw is manipulated when the operator desires to change the width of the bags 162. Of course, the adjustments in the position of the holder 95 with reference to the guide rails 94 are dependent on the selected distance between the vertical seams which are formed by the welding devices 6.

The conveyor 10 comprises two parallel horizontal guide railsor ways 105, 106 (see FIGS. 2, 5 and 6) which are normal to the tie rods 19 for the carriages 3, 4 and support and guide reciprocable slides 107, 108. The

slides

107, 108 respectively support pairs of grippers or

tongs

109, 110 and 111, 112.

The guide rails 105, 106 are respectively mounted on vertically

movable columns

113, 114. Each of these columns is movable between an upper end position, an intermediate position and a lower end position by lifting means including linkages 115, bell cranks 117 having pairs of roller followers 116 and cams 118 on the camshaft 104. The roller followers 116 track the respective cams 118.

The

slides

107, 108 are movable along the

guide rails

105, 106 between three predetermined positions. Such movements are imparted to the'slides 107, 108 by cams 119 on the camshaft 104, levers 120 having roller followers which track the cams 119, bell cranks 122 which are connected with the levers 120 by rods 121, and rods 123 which connect the bell cranks 122 with the respective slides.

Each of the grippers or

tongs

109, 110, 111, 112 comprises a first jaw 124 which is rigidly secured to the

respective slide

107 or 108, and a second jaw 125 which is movable toward and away from the associated fixed jaw 124. Each of the movable jaws 125 is mounted on levers 126, 127 which are pivotally se-. cured to the

respective slide

107 or 108. The levers 126, 127 have arms 128 for roller followers 129. Springs 130 bias the arms 128 toward each other so as to urge the respective jaws 125 toward the associated jaws 124 and to thus close the

gripper

109, 110, 111 or 112. The

slides

107, 108 further carry

cams

131, 132 which are turnable between several positions and are located above the respective roller followers 129. The

cams

131, 132 can move the one and/or the other of the adjacent roller followers 129 to thereby open a single gripper or both grippers on the respective slide. The

cams

131, 132 receive motion from further cams 133 by way of levers 134, rods 135, bell cranks 136 and rods 137.

When held in its lower end position, the slide 107 can readily move past the slide 108 while the latter is held in the upper end position, and vice versa. That slide which travels from the severing device 9 toward the conveyor 11 is maintained in the lower end position and the slide which travels from the conveyor 9 toward the severing device 9 is maintained in the upper end position, at least until it advances past the other slide.

The second conveyor 11 is illustrated in FIGS. 2,

and 7. This conveyor comprises two

endless chains

140, 141 of identical length which are disposed in horizontal planes at different levels and are trained over pairs of coaxial sprocket wheels 142 (only one pair shown). Certain links 143 of the

chains

140, 141 are provided with registering eyes 144 for

pivotable levers

145, 146. The upper portions of the

levers

145, 146 have horizontal arms 147 which extend transversely of the direction of travel of the respective chains and each of which supports apair of clamping devices each having two clamping elements 148. The clamping elements 148 travel along two parallel paths which are disposed side-by-side. As shown in FIG. 2, the clamping elements 148 on a preceding arm 147 face rearwardly and the clamping elements 148 on the next-following arm 147 face forwardly.

The means for opening the clamping devices (i.e., for moving one of a'pair of clamping elements 148 awayfrom the other clamping element). comprises an elongated bar or rail 149 provided with rollers 150 and mounted on a support 151. The latter is carried by two

levers

153, 154 which are pivotable on a bearing block 152. The lever 153 is pivotable by a rocking mechanism including a rod 155 in such a way that the bar 149 descends at certain intervals to move the rollers 150 downwardly whereby the rollers 150 open the corresponding clamping devices on the arms 147.

Since the grippers 109-112 move upwardly during insertion of bags 162 into the adjacent clamping devices on the conveyor 11, the upper edges of the bags 162 on the conveyor 11 are located at a level above the upper edges of the bags which form the row 161a (see FIG. 5). The difference between the two levels depends on the dimensions of the bags; such difference can be in the range of 15-25 millimeters. FIG. 5 further shows that, once the

grippers

111, 112 of the slide 108 are relieved of the bags 162, they are caused by the column 114 to rise to a level above the upper edges of such freshly transferred bags and are thereupon free to bypass the

grippers

109, 110 on the slide 107. The same applies for the

grippers

109, 110 when such grippers complete the delivery of a pair of bags 162 to two clamping devices of the conveyor 11. It will be seen that the

slides

107, 108 are movable between lower end positions in which their grippers receive bags 162 at the severing station, intermediate positions in which their grippers hold the bags in optimum positions for engagement and retention by the clamping devices of the conveyor 11, and upper end positions in which the grippers can move above the freshly transferred bags on the conveyor 11 and above that slide which approaches the conveyor 11.

The operation:

The supply roll 1160 contains a convoluted web 160 which consists of flexible material and at least one side of which is weldable in response to the application of heat. The web 160 is drawn from the roll 1160 to pass between the plates 12, 13 of the folding plow and thereupon between the pairs of vertical pressing bars 14 so as to be converted into a folded web 161 consisting of two face-to-face strips each having a height corresponding to the desired length or height of a bag 162. The leader of the folded web 161 is placed between the feed rolls 7, 8. The weldable sides of the strips which form the folded web 161 face each other.

When the machine is started, the web feeding or advancing devices 5 of the carriages 3, 4 intermittently withdraw from the roll 1160 predetermined lengths of the web 160 and advance the thus withdrawn lengths in a direction toward the severing unit 9. The feed rolls 7, 8 assist the devices 5 on the carriages 3 and 4. The welding or sealing devices 6 of the carriages 3, 4 are closed while the associated web feeding devices 5 grip the folded web 161 whereby the bars of the welding devices 6 provide longitudinally spaced portions of the web 161 with transverse vertical seams to thus convert the web 161 into a row 161a of interconnected bags 162. The width of the seams formed by the bars of the welding devices 6 is twice the width of the vertical seam on a bag 162 which is separated from the row 161a. The feed rolls 7, 8 advance the row 161a stepwise toward the severing device 9 whose movable knife 98jis pivoted relative to the fixed knife 96 while the row 161a is at a standstill whereby the

knives

96, 98 sever the row across a vertical seam to separate a bag 162 from the leading end of such row. The holder for the

knives

96, 98 is positioned with reference to the center of the first conveyor 10 in such a way that the freshly severed bag 162 is located substantially midway between the

guide rails

105, 106 and extends transversely of the direction of reciprocatory movement of the

slides

107, 108.

The width of the bags 162 is determined by appropriate adjustment of the arms 36 on the bell cranks 26 and 34. Such arms control the length of strokes of the carriages 3, 4 on the tie rods 19. Once the selection of the strokes of the carriages 3, 4 is completed, the driving parts for the carriages are moved to their median positions and the carriages 3, 4 are shifted by means of pinions 42 with reference to the

racks

39, 40 so that the distance between the centers of the welding devices 6 and the center of the first conveyor 10 is a whole multiple of the width of a bag 162. The

racks

39, 40 are thereupon fixedly secured to the carriages 3 and 4.

The grippers 109-112 are moved seriatim into alignment with the path for the row 161a. The guide rail or 106) which supports that gripper which is in alignment with the row 1610 is maintained in its lower end position. FIG. 2 shows that the gripper on the slide 107 is in line with the row 161a; therefore, the guide rail 105 for the slide 107 is maintained in its lower end position. The gripper 110 is open while the feed rolls 7, 8 advance the row 161a through such a distance that the foremost bag 162 of the row 161a extends beyond the

knives

96, 98. The gripper 110 is thereupon closed and the knife 98 is moved with reference to the knife 96 to sever from the row 161a that bag 162 which is held by the jaws of the gripper 110. The gripper 109 is assumed to hold a bag 162 which was severed from the row 161a during the preceding stage of the operation. The slide 107 thereupon transports the grippers 109, 110 (each carrying a bag 162) along the

guide rails

105, 106 in a direction toward the transfer station between the

conveyors

10 and 11. The slide 107 is arrested when its

grippers

109, 110 register with two clamping devices of the conveyor 11. The

grippers

109, 110 are located at a level below the adjacent clamping devices.

In the next step, the column 113 is caused to move the guide rail 105 and the slide 107 upwardly so that the lateral portions of the bags 162 enter into the spaces between the clamping elements 148 of the respective clamping devices. These clamping devices are open during upward movement of the column 113 so that they can properly receive the bags 162 from the

grippers

109, 110. The clamping devices including the elements 148 are thereupon closed and the

grippers

109, 110 are caused to open so that the bags 162 are transferred onto and are supported by the conveyor 11. The slide 107 is then caused to move back toward the severing unit 9 and descends with the guide rail 105 so that its

grippers

109, 110 are ready to receive a fresh pair of bags 162. The sprocket wheels 142 for the

chains

140, 141 are indexed by a step while the slide 107 moves back toward the severing device 9 so that the

chains

140, 141 place the next-following pair of clamping devices into requisite positions for reception of bags 162 from the

grippers

111, 112 of the slide 108. The

grippers

111, 112 receive freshly severed bags 162 during transfer of bags from the grippers 109, .110 to the clamping devices on the conveyor 11. Thearrangement is preferably such that the slide 108 travels in a direction toward the conveyor 11 while the slide 107 travels away from the conveyor 11, and vice versa. Each of the

slides

107, 108 is movable along the

ways

105, 106 between three positions in the first of which the

gripper

109 or 111 is located in a bag receiving position, in the second of which the gripper 110 or'112 is located in such bag receiving position, and in the third of which the

grippers

109, 110 or 111, 1 12 register with pairs of clamping devices on the conveyor 11.

The manner in which the bags 162 which are held by the clamping devices of the conveyor 11 are opened, filled, sealed, cooled and/or otherwise processed forms no part of the present invention.

Referring more specifically to the operation of the bag making and forming unit 2, the gripper on the carriage 3 is closed to grip the folded web 161 during travel of the carriage 3 from the left-hand end position (shown in FIG; 1 by solid lines) to the right-hand end position 3' (shownin FIG. 1 by phantom lines). The gripper 5 of the carriage 3 is open when the carriage moves from the position 3' to the solid-line position of FIG. 1. The gripper 5 on the carriage 4 is open while this carriage moves from the solid-line position to the phantom-line position 4' of FIG. 1, and the gripper of the carriage 4 clamps and transports the folded web 161 (arrow 180) while the carriage 4 moves from the phantom-line position 4' to the solid-line position of FIG. 1. The movements of carriages 3, 4 are programmed by the earns 20, 28 in such a way that the row 161a downstream of the carriage 4 contains a series of interconnected bags 162 of desired width. The bars of the welding devices 6 provide the folded web 161 with transverse seams while the respective carriages advance in the direction indicated by the arrow 180, Le, while the web 161 is engaged and transported by the corresponding gripper 5. As mentioned above, the interval during which a welding device 6 provides the folded web 161 with a transverse seam at most equals the length of the interval during which the web 161 is advanced by the respective gripper 5. It will be noted that the bag making or forming unit 2 makes a single seam at a time. This renders it'possible to transport the web 161 lengthwise at frequent intervals and with a high degree of accuracy. Also, since a single bag 162 extends beyond the cutting plane defined by the edge of the knife 96, the leader of the row 161a is not likely to flex under its own weight and can enter the gap between the elements of the

adjacent gripper

109, 110, 111 or 112 in an accurately determined position to insure that the severed bag 162 can be readily transferred to and properly engaged by a clamping device on the conveyor 11.

If desired, the conveyor 11 which transports two files or rows of discrete bags past one or more processing stations can be mounted to advance the bags 162 in a direction counter to that indicated by the arrow 180 (see FIG. 2). This reduces the overall length of the machine because at least some of the processing stations can be located behind or in front of the web folding and bag making units 1 and 2. I

It is further clear that the conveyor 10 can be modified to transport to the conveyor 1 1 a single bag 162 or three or more bags at a time and that the conveyor 11 can transport more than two rows of such bags.

Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can, by applying current knowledge, readily adapt it for variousapplication's without omitting features which fairly constitute essential characteristics of the generic and specific aspects of our contribution to the art and, therefore, such adaptations should and are intended to be comprehended within the meaning and range of equivalence of the claim-s.

What is claimed as new and desired to be protected by Letters Patent is set forth in the appended claims.

We claim:

1. In a machine for making and manipulating bags or analogous containers, a combination comprising a supply of flexible web consisting at least in part of weldable material; feeding means for drawing the web from said supply and for intermittently advancing the web lengthwise along a predetermined path; a folding unit disposed between said supply and said feeding means for converting the withdrawn web into a folded web having to said direction and vice versa, and means for moving that welding device which moves in said direction into engagement with the folded web so that the two welding devices form one seam at a time, said feeding means comprising first and second advancing devices respectively arranged to share the movements of said first and second welding devices in and counter to said direction and means for maintaining said advancing devices in motion transmitting engagement with the folded web at least while the folded web is engaged by the respective welding devices, and severing means for separating successive foremost containers from said row.

2. A combination as defined in claim 1, further comprising first conveyor means for advancing containers lengthwise along a plurality of second paths, and second conveyor means for transporting containers sideways from said severing means to said first conveyor means.

3. In a machine for making and manipulating bags or analogous containers, a combination comprising a supply of flexible web consisting at least in part of weldable material; folding means for drawing the web from said supply and for advancing the web lengthwise along a predetermined path; a folding unit disposed between said supply and said feeding means for converting the withdrawn web into a folded web having two overlapping strips; a forming unit comprising first and second welding devices located one behind the other as considered in the direction of travel of the web along said path and movable into and from welding engagement with the folded web downstream of said folding unit to provide the folded web with transverse seams and to thus convert the folded web into a row of interconnected containers, means for moving said first welding device in the direction of travel of the folded web while said second welding device is moved counter to said direction and vice versa, and means for moving that welding device which moves in said direction into engagement with the folded web so that the two welding devices form one seam at a time; severing means for separating successive foremost containers from said row; first conveyor means comprising two rows of clamping devices for advancing containers lengthwise along two discrete paths at least a portion of each of which is at least substantially parallel to said first mentioned path; and second conveyor means for transporting containers sideways from said severing means to said first conveyor means, said second conveyor means comprising a plurality of grippers arranged to deliver pairs of containers from said severing means to said first conveyor means so that one of each pair of containers is received by a clamping device of one of said rows of clamping devices and the other container of such pair of containers is received by a clamping device of the other row of said clamping devices.

4. In a machine for making and manipulating bags or analogous containers, a combination comprising a supply of flexible web consisting at least in part of weldable material; feeding means for drawing the web from said supply and for advancing the web lengthwise, along a predetermined path; a folding unit disposed between said supply and said feeding means for converting the withdrawn web into a folded web having two overlapping strips; a forming unit comprising two welding devices movable into and from welding engagement with the folded web downstream of said folding unit to provide the folded web with transverse seams and to thus convert the folded web into a row of interconnected containers, means for moving one of said devices in the direction of travel of the folded web while the other device is moved counter to said direction and vice versa, and means for moving that welding device which moves in said direction into engagementwith the folded web so that said two devices form one seam at a time; severing means for separating successive foremost containers from said row; and conveyor means for receiving containers from said severing mean-s and for moving such containers substantially transversely of said path, said conveyor means comprising a pair of slides, guide means defining for said slides a second path which is inclined with reference to said first mentioned path, normally open gripper means provided on said slides, means for moving said gripper means to and from a receiving position downstream of said severing means so that such gripper means can receive the foremost container of said row, and means for closing the gripper means in said receiving position not later than upon completion of severing of the foremost container.

5. A combination as defined in claim 4, wherein each of said slides is provided with a plurality of discrete gripper means.

6. A combination as defined in claim 4, wherein said conveyor means further comprises means for moving said slides between a plurality of levels.

7. A combination as defined in claim 6, wherein said means for closing the gripper means is operative when the respective slide is located at the lowest of said plurality of levels.

8. A combination as defined in claim 7, further comprising second conveyor means having plural rows of clamping devices for containers, said gripper means being arranged to place containers within reach of said clamping devices when the respective slides are located at a level above said lowest level. 9. A combination as defined in claim 8, wherein said second conveyor means comprises a pair of endless flexible elements disposed in horizontal planes located at, different levels, means for moving said flexible elements in stepwise fashion, and means for opening and closing said clamping devices at predetermined intervals.

10. In a machine for making and manipulating bags or analogous containers, a combination comprising a supply of flexible web consisting at least in part of weldable material; feeding means for drawing the web from said supply and for advancing the web lengthwise along a predetermined path; a folding unit disposed between said supply and said feeding means for converting the withdrawn web into a folded web having two overlapping strips; a forming unit comprising a leading carriage and a trailing carriage, said carriages being spaced from each other along said path downstream of said folding unit, reciprocating means for moving one of said carriages in the direction of web travel along said path and for simultaneously moving the other of said carriages counter to said direction, a welding device provided on each of said carriages, and actuating means for placing said welding devices into engagement with the folded web while the respective carriages move in said direction so that the welding devices provide the folded web with transverse seams to thus convert the folded web into a row of interconnected containers, said actuating means comprising pneumatic cylinders and conduit means for supplying a pressurized fluid to said cylintiers; and regulating means for changing the length of periods of engagement between the folded web and said welding devices, said regulating means comprising adjustable valve means provided in said conduit means and adjustable timer means for controlling the closing of said valve means.

11. A combination as defined in claim 10, wherein said regulating means further comprises means for opening said valve means in response to actuation of said feeding means.

12. A combination as defined in claim 11, wherein said feeding means comprises a normally open advancing device provided on each of said carriages and means for maintaining said advancing devices in motion transmitting engagement with the folded web during movement of the respective carriages in said direction, said means for opening said valve means being responsive to movement of respective advancing devices into engagement with the folded web.

13. In a machine for making and manipulating bags or analogous containers, a combination comprising a supply of flexible web consisting at least in part of weldable material; feeding means for drawing the web from said supply and for advancing the web lengthwise along a predetermined path; a folding unit disposed between said supply and said feeding means for converting the withdrawn web into a folded web having two overlapping strips; and a forming unit comprising a pair of carriages spaced from each other along said path downstream of said folding unit, reciprocating means for .moving one of said carriages in the direction of web travel along said path and'for simultaneously moving the other carriage counter to said direction, a welding device provided on each of said carriages, each of said welding devices comprising a pair of heated welding members disposed at the opposite sides of said path, and actuating means for placing said welding devices into welding engagement with the folded web while the respective carriages move in said direction so that the welding devices provide the folded web with transverse seams to thus convert thefolded web ,into'a row of interconnected containers, ,said actuating means comprising means for moving at least one of said welding members toward the other welding member to thereby place the folded web into engagement with such welding members, said last mentioned means comprising a pair of first lever means pivotably mounted on the respective carriage and supportingsaid welding members, follower means provided on said first lever means, cam means movably mounted on the respective carriage, means for biasing said follower means against said cam means, and means for moving said cam means including a rotary shaft supporting said cam means, second lever meanssecured to said shaft, a control member coupled to said second lever means, pneumatic cylinder means having reciprocable piston rod means, and further lever means for pivoting said second lever means in response to movement of said piston rod means.

14. In a machine for making and manipulating bags or analogous containers, wherein a row of interconnected containers is advanced lengthwise along a first path, a combination comprising severing means for separating successive foremost containers from the row of interconnected containers; first conveyor means for receiving separated containers from said severing means and for moving groups of the thus separated containers transversely of said path; and second conveyor means for receiving groups of containers from said first conveyor means and for transporting the containers of such groups along a plurality of second paths each of which is parallel to said first path.

15. A combination as defined in claim 14, wherein said second conveyor means comprises a plurality of endless flexible elements provided with longitudinally spaced clamping devices for containers and said first conveyor means comprises a plurality of reciprocable slides each provided with several gripping devices for containers.

16. A combination as defined in claim 15, wherein said first conveyor means further comprises means for moving said slides between a plurality of levels.

17. A combination as defined in claim 15, further comprising cam-operated means for opening and closing said gripping and clamping devices in a predetermined sequence.

18. In a machine for making and manipulating bags or analogous containers, a combination comprising a supply of flexible web consisting at least in part of weldable material; feeding means for drawing the web from said supply and for intermittently advancing the web lengthwise along a predetermined path; a folding unit disposed between said supply and said feeding means for converting the withdrawn web into a folded web having two overlapping strips; 21 forming unit comprising a leading carriage and a trailing carriage said carriages being spaced from each other along said path downstream of said folding unit, recirpocating means for moving one of said carriages in the direction of web travel along said path and for simultaneously moving the other carriage counter to said direction, a welding device provided on each of said carriages, and actuating means for placing said welding devices into welding engagement with the folded web while the respective carriages move in said direction so that the welding devices provide the folded web with transverse seams to thus convert the folded web into a row of interconnected containers, said feeding means comprising first and second normally open advancing devices respectively mounted on said leading and trailing carriages and means for maintaining said advancing devices in motion transmitting engagement with the folded web at least while the folded web is engaged by the respective welding devices; and regulating means for changing the web and said welding devices.

Claims

1. In a machine for making and manipulating bags or analogous containers, a combination comprising a supply of flexible web consisting at least in part of weldable material; feeding means for drawing the web from said supply and for intermittently advancing the web lengthwise along a predetermined path; a folding unit disposed between said supply and said feeding means for converting the withdrawn web into a folded web having two overlapping strips; a forming unit comprising first and second welding devices located one behind the other as considered in the direction of travel of the web along said path and movable into and from welding engagement with the folded web downstream of said folding unit to provide the folded web with transverse seams and to thus convert the folded web into a row of intErconnected containers, means for moving said first welding device in the direction of travel of the folded web while said second welding device is moved counter to said direction and vice versa, and means for moving that welding device which moves in said direction into engagement with the folded web so that the two welding devices form one seam at a time, said feeding means comprising first and second advancing devices respectively arranged to share the movements of said first and second welding devices in and counter to said direction and means for maintaining said advancing devices in motion transmitting engagement with the folded web at least while the folded web is engaged by the respective welding devices, and severing means for separating successive foremost containers from said row.

4. In a machine for making and manipulating bags or analogous containers, a combination comprising a supply of flexible web consisting at least in part of weldable material; feeding means for drawing the web from said supply and for advancing the web lengthwise along a predetermined path; a folding unit disposed between said supply and said feeding means for converting the withdrawn web into a folded web having two overlapping strips; a forming unit comprising two welding devices movable into and from welding engagement with the folded web downstream of said folding unit to provide the folded web with transverse seams and to thus convert the folded web into a row of interconnected containers, means for moving one of said devices in the direction of travel of the folded web while the other device is moved counter to said direction and vice versa, and means for moving that welding device which moves in said direction into engagement with the folded web so that said two devices form onE seam at a time; severing means for separating successive foremost containers from said row; and conveyor means for receiving containers from said severing means and for moving such containers substantially transversely of said path, said conveyor means comprising a pair of slides, guide means defining for said slides a second path which is inclined with reference to said first mentioned path, normally open gripper means provided on said slides, means for moving said gripper means to and from a receiving position downstream of said severing means so that such gripper means can receive the foremost container of said row, and means for closing the gripper means in said receiving position not later than upon completion of severing of the foremost container.

8. A combination as defined in claim 7, further comprising second conveyor means having plural rows of clamping devices for containers, said gripper means being arranged to place containers within reach of said clamping devices when the respective slides are located at a level above said lowest level.

9. A combination as defined in claim 8, wherein said second conveyor means comprises a pair of endless flexible elements disposed in horizontal planes located at different levels, means for moving said flexible elements in stepwise fashion, and means for opening and closing said clamping devices at predetermined intervals.

10. In a machine for making and manipulating bags or analogous containers, a combination comprising a supply of flexible web consisting at least in part of weldable material; feeding means for drawing the web from said supply and for advancing the web lengthwise along a predetermined path; a folding unit disposed between said supply and said feeding means for converting the withdrawn web into a folded web having two overlapping strips; a forming unit comprising a leading carriage and a trailing carriage, said carriages being spaced from each other along said path downstream of said folding unit, reciprocating means for moving one of said carriages in the direction of web travel along said path and for simultaneously moving the other of said carriages counter to said direction, a welding device provided on each of said carriages, and actuating means for placing said welding devices into engagement with the folded web while the respective carriages move in said direction so that the welding devices provide the folded web with transverse seams to thus convert the folded web into a row of interconnected containers, said actuating means comprising pneumatic cylinders and conduit means for supplying a pressurized fluid to said cylinders; and regulating means for changing the length of periods of engagement between the folded web and said welding devices, said regulating means comprising adjustable valve means provided in said conduit means and adjustable timer means for controlling the closing of said valve means.

13. In a machine for making and manipulating bags or analogous containers, a combination comprising a supply of flexible web consisting at least in part of weldable material; feeding means for drawing the web from said supply and for advancing the web lengthwise along a predetermined path; a folding unit disposed between said supply and said feeding means for converting the withdrawn web into a folded web having two overlapping strips; and a forming unit comprising a pair of carriages spaced from each other along said path downstream of said folding unit, reciprocating means for moving one of said carriages in the direction of web travel along said path and for simultaneously moving the other carriage counter to said direction, a welding device provided on each of said carriages, each of said welding devices comprising a pair of heated welding members disposed at the opposite sides of said path, and actuating means for placing said welding devices into welding engagement with the folded web while the respective carriages move in said direction so that the welding devices provide the folded web with transverse seams to thus convert the folded web into a row of interconnected containers, said actuating means comprising means for moving at least one of said welding members toward the other welding member to thereby place the folded web into engagement with such welding members, said last mentioned means comprising a pair of first lever means pivotably mounted on the respective carriage and supporting said welding members, follower means provided on said first lever means, cam means movably mounted on the respective carriage, means for biasing said follower means against said cam means, and means for moving said cam means including a rotary shaft supporting said cam means, second lever means secured to said shaft, a control member coupled to said second lever means, pneumatic cylinder means having reciprocable piston rod means, and further lever means for pivoting said second lever means in response to movement of said piston rod means.

18. In a machine for making and manipulating bags or analogous containers, a combination comprising a supply of flexible web consisting at least in part of weldable material; feeding means for drawing the web from said supply and for intermittently advancing the web lengthwise along a predetermined path; a folding unit disposed between said supply and said feeding means for converting the withdrawn web into a folded web having two overlapping strips; a forming unit comprising a leading carriage and a trailing carriage said carriages being spaced from each other along said path downstream of said folding unit, recirpocating meAns for moving one of said carriages in the direction of web travel along said path and for simultaneously moving the other carriage counter to said direction, a welding device provided on each of said carriages, and actuating means for placing said welding devices into welding engagement with the folded web while the respective carriages move in said direction so that the welding devices provide the folded web with transverse seams to thus convert the folded web into a row of interconnected containers, said feeding means comprising first and second normally open advancing devices respectively mounted on said leading and trailing carriages and means for maintaining said advancing devices in motion transmitting engagement with the folded web at least while the folded web is engaged by the respective welding devices; and regulating means for changing the length of periods of engagement between the folded web and said welding devices.