US3324624A

US3324624A - Wrapping machine

Info

Publication number: US3324624A
Application number: US333072A
Authority: US
Inventors: Mayer Rudolf
Original assignee: CARL DROHMANN GmbH
Current assignee: CARL DROHMANN GmbH
Priority date: 1963-02-05
Filing date: 1963-12-24
Publication date: 1967-06-13
Anticipated expiration: 1984-06-13
Also published as: GB1021065A; CH411677A

Description

R. MAYER June 13, 1967 WRAPPING MACHINE Filed Dec. 24, 1965 FIG. 7

FIG. 2

3,324,524 Patented June 13, 1967 D ,8 8 Claims. (Cl. 53-230) This invention is concerned with a wrapping machine in which articles to be wrapped are each fed with a wrapper through a folding tube, so that the wrapper is folded into U-shape around the article, by one of a number of drivers associated with an endless conveyor chain which runs around reversing wheels.

In wrapping machines it is known to effect the insertion of articles into the folding tube by means of a pusher which is movable to and fro. Since the return movement of the pusher to its initial position in the timing of the machine involves a dead period, the output of such machines is somewhat small. It has, therefore, already been proposed to let the pusher return to its initial position above or below the path of feed of the articles at the end of each pushing operation. This provision has proved to be satisfactory in machines in which the pusher performs a short stroke but in machines with a longer pushing stroke, for example wrapping machines for large packages or composite packages, involves an unacceptable overall length of the machine. In order to prevent the pusher returning to. a position in the path of feed of the articles, it has, moreover, already been proposed to mount one or more drivers on an endless conveyor chain which circulates in an oval-shaped path, so that at the end of the feed section, i.e. the section of the conveyor over which the drivers feed the articles through the folding tube, each driver is drawn downwardly or upwardly away from the rear side of the article being conveyed, is

pivoted out of the path of feed and is returned to its original position along another path. A return movement of each driver in a direction perpendicularly with respect to the rear side of the article being conveyed, as with sliders which are movable to and fro rectilinearly, is, however, not achieved with this type of conveyor movement. This is disadvantageous insofar as the ends of the wrapper projecting beyond the rear side of each article to be wrapped may be disarranged by the slider.

In order to obviate these disadvantages, the present invention provides a machine in which articles to be wrapped are each fed with a wrapper through a folding tube, so that the wrapper is folded into U-shape around the article, by one of a number of drivers associated with an endless conveyor chain which runs around reversing wheels each forming a reversing section of the conveyor, and the drivers are each pivotally coupled to the conveyor chain by at least one rod and are guided in stationary rails for movement therealong, the arrangement being such that, when the pivot on the conveyor chain of the rod of each driver passes around a reversin section of the conveyor chain, the driver concerned is reversed.

In accordance with a further feature of the invention, the rails for guiding the drivers during their feeding movement, i.e. whilst they are feeding articles through the folding tube, their return movement to a position in readiness for a fresh feeding movement, and their reversal, are of hysteresis loop form. Thus, each driver is moved out of the path of feed after leaving the rear side of the article being fed thereby, and is brought back to its original position in readiness for a fresh feeding movement along a path other than the path of feed. The rails may have switches at the ends of the said hysteresis loop, each switch being constituted by a tongue which controls the reversal of the drivers.

In addition to a more careful handling of the wrappers than in machines with a reciprocating pusher, an output which is at least doubled, is attained by the machine of the present invention whilst operating at the same speed of conveyance.

A preferred embodiment of a wrapping machine according to the invention will now be described with reference to the accompanying diagrammatic drawings.

In the drawings:

FIGURE 1 is a longitudinal section through the wrapping machine.

FIGURE 2 is a plan view, partly cut away, of the wrapping machine shown in FIGURE 1, and

FIGURE 3 is a side view, on an enlarged scale, on one of the drivers showing it in a further position from FIGURE 1.

The wrapping machine illustrated in the drawings is particularly suitable for wrapping large articles G or groups of identical smaller articles or packages in wrappers E. The method of wrapping chosen for the present example is that known as pocket folding in which a wrapper is first folded in U-shape around the front, upper and lower sides of each article, whereupon the two projecting parts of the wrapper at the ends of the article are folded in and then the rear side of the article is enclosed by the wrapper.

In order to fold a wrapper E in U-shape around an article G, the latter is brought in the known way up against the wrapper E, which is fed in in a vertical plane. The article and the wrapper are then pushed through a folding tube 1 which is provided at both its sides with folding

members

2, 3 and 4 for folding in the wrapper at the ends of the packagePushing of the articles G is performed successively by four drivers 5 which are connected to a pair of endless conveyor chains 8 which circulate continuously around two pairs of reversing

wheels

6, 7 in the direction of the arrows shown in FIGURES 1 and 3. One pair of reversing wheels, 6 or '7, is driven by any suitable means, e.g. an electric motor. Each of the drivers 5 comprises a pushing plate 10, a frame 11 and a carriage 12 and the drivers, are guided in two sets of rails 14 of U-shape in cross section by means of rollers 13 which are mounted on the carriages i2 and run in the rails. Pivoted to the carriage 12 of each driver 5 are the ends of two rods 15 which are pivotally connected at their other ends to the conveyor chains 3.

The two sets of rails 14 are arranged below the table 16 of the machine on which the articles G are fed, and the path of these rails is of hysteresis loop form with two tracks, viz. an upper and a lower track, and two switches constituted by two pairs of

pivotable tongues

17 and 18. The drivers 5 are drawn along the upper track of the rails and pushed along the lower, return track by the conveyor chains 8. The rails are so associated with the conveyor chains 8 that each driver 5 has imparted to it a reversing movement at the end of the upper track, i.e. at the end of its feed movement, when the leading pivots of the associated two rods 15 on the conveyor chains 8 pass around .the reversing section of the chains 8 formed by the reversing wheels 7, so that, after being influenced by the switch 17 arranged beneath the path of feed of the articles, i.e. beneath the machine table 16, the driver is pushed to a switch 18 at the other end of the hysteresis loop where it again receives a reversing movement by the switch 18 and is then drawn along the upper track.

The lengths of the rods 15 and the diameters of the reversing

wheels

6 and 7 are so correlated that these parts have the same effect as a crank drive. In addition,

the

switches

17 and 18 are of such a form that, after a O initiation of the reversing movement of each driver 5, its carriage 12 is automatically brought on to the next rail track. Thus, the two pivotable tongues of each switch operate in a similar way to a switch in a railroad system. Provided on each of the pivotable tongues of the switch 17 is a counter weight 23 which biases the tongue to a normal rest position in the upper track of the U-section rail 14. Thus, when a driver enters the switch 17 from the upper track, the .tongues are swung downwardly to allow the driver to move to the position shown in FIGURE 1.

The tongues then return to their normal positions and, when the driver concerned is moved out of the switch, cause it to move on to the lower track. The pivotable tongues of the switch 18 are controlled in the same manner but under their own weight.

During the feed of an article G, a part of the frame 11 with the pushing plate 10 pivoted thereto projects up through a longitudinal slot 19 formed in the machine table 16. A pivotable plate 20 is mounted in the machine table 16 for the purpose of guiding each pushing plate 10 through the machine table 16 at the end of the feed movement of the driver concerned. This plate 20 is periodically swung downwardly so that a free space is formed for the passage therethrough of a pushing plate 10 (as shown in FIGURE 3). In order to maintain this space small, the pushing plate 10 of each driver is pivoted into a horizontal position on the return movement of the driver. To this end, there is arranged on the folding tube 1 a pivotable pawl 21 against which the pushing plate 10, which during feed is held in a vertical position by a permanent magnet 22 secured on the frame 11, runs so that the plate is released from the magnet 22 and pivoted through 90.

Since, in the present example, the pivot pins 27 which connect the rods to the conveyor chains 8, intersect the rails 14 at two parts thereof during movement of the drivers 5 around the rails 14, each set of rails 14 is provided with

pivotable parts

28 and 29 to allow for passage of the pins 27 therethrough.

The parts of the wrapper at the rear side of the package are .then folded down by means of folding members 25, 26 (FIGURE 1) at the working station to which the articles G come at the end of their feed by the drivers 5. The further conveyance of the finished packages to the outlet of .the machine is still performed by the drivers 5 as the fresh articles G fed to the said working station advance the preceding articles.

I claim:

1. A wrapping machine comprising a base frame; a folding tube mounted on the base frame; an endless conveyor chain which runs around reversing wheels carried by the base frame, each reversing wheel forming a reversing section of the conveyor chain; means for circulating .the conveyor chain around the reversing wheels; guide rails fixed to the base frame alongside the conveyor chain and defining a path constituted by an upper track and a lower track with intersecting portions; a number of drivers guided on said guide rails for movement therealong, at least one rod pivotally coupling each driver to the conveyor chain, each driver being arranged to move through the folding tube to push an article to be wrapped and a wrapper through the tube so that the wrapper is folded into U-shape around the article; and means associated with the guide rails adjacent the reversing sections of the conveyor chain for switching the drivers from one track to the other and reversing their direction of travel as the pivots on the conveyor chain of the said rods pass around the reversing sections.

p 2. A wrapping machine comprising a base frame; a folding tube mounted on the base frame; an endless conveyor chain which runs around reversing wheels carried by the base frame, each reversing wheel forming a reversing section of the conveyor chain; means for circulating the conveyor chain around the reversing wheels; guide rails which are fixed to the base frame alongside the conveyor chain and are of hysteresis loop form defining an upper and lower track with intersecting portions adjacent the said reversing sections; a number of drivers guided on said guide rails for movement therealong, at least one rod pivotally coupling each driver to the conveyor chain, each driver being arranged to move through the folding tube to push an article to be wrapped and a wrapper through the .tube so that the wrapper is folded into U-shape around the article; and means associated with the intersecting portions of the hysteresis loop for switching the drivers from one track to the other and reversing the direction of travel of the drivers as the pivots on the conveyor chain of the said rods pass around the reversing sections.

3. A wrapping machine comprising a base frame; a folding tube mounted on the base frame; and endless conveyor chain which runs around reversing wheels carried by the base frame and has a straight section extending alongside the folding tube, each reversing wheel forming a reversing section of the conveyor chain; means for circulating the conveyor chain around the reversing wheels; a number of drivers, at least one rod pivotally coupling each driver to the conveyor chain such that each driver is arranged to move, along the said straight section of the conveyor chain, through the folding tube to feed an article to be wrapped and a wrapper through the tube so that the wrapper is folded into U-shape around the article; guide rails of hysteresis loop form fixed to the base frame alongside the conveyor chain and defining an upper and lower track with intersecting portions and with the ends of the hysteresis loop and adjacent the said reversing sections, the aforesaid drivers being guided on the guide rails for movement therealong when feeding articles through the folding tube and when being returned to a position in readiness for a fresh feeding movement; and switches, each constituted by a tongue, at the ends of the hysteresis loop for switching the drivers from one track to the other while the direction of travel of the drivers is reversed as the pivots on the conveyor chain of the said rods pass around the reversing sections of the conveyor chain.

4. A wrapping machine as claimed in claim 3, wherein there are a pair of conveyor chains which run parallel to, and are spaced from, one another, and two sets of guide rails associated respectively with the two conveyor chains, the drivers being mounted between the spaced, parallel guide rails.

5. A wrapping machien as claimed in claim 4, wherein the guide rails are of U-shape in cross section for guiding the drivers.

6. A wrapping machine comprising a base frame; a horizontal table which is mounted on the base frame and on which articles to be wrapped are fed into the machine; a folding tube mounted in a horizontal disposition on the base frame above the said table; an endless conveyor chain which runs around two reversing wheels carried by the base frame and has a horizontal straight section disposed below and adjacent to the aforesaid table, each reversing wheel forming a reversing section of the conveyor chain; means for circulating the conveyor chain around the reversing wheels; guide rails fixed to the base frame alongside the conveyor chain and a horizontal upper track and a lower track with intersecting portions adjacent the reversing sections; a number of drivers guided on said guide rails for movement therealong, at least one rod pivotally coupling each driver to the conveyor chain, each driver being arranged to move, along the said straight section of the conveyor chain, through the folding tube to push an article to be wrapped and a wrapper through the tube so that the wrapper is folded into U-shape around the article; and means associated with the intersecting portions of the guide rails adjacent the reversing sections of the conveyor chain for switching the drivers from one track to the other while the direction of the drivers is rcversed as the pivots on the conveyor chain of the said rods pass around the reversing sections.

7. A wrapping machine comprising a base frame; a folding tube mounted on the base frame; an endless conveyor chain which runs around reversing wheels carried by the base frame, each reversing wheel forming a reversing section of the conveyorv chain; means for circulating the conveyor chain around the reversing wheels, guide rails fixed to the base frame alongside the conveyor chain; a number of drivers guided on said guide rails for movement therealong at least one rod pivotally coupling each driver to the conveyor chain, each driver being arranged to move through the folding tube to push an article to be wrapped and a wrapper through the tube so that the wrapper is folded into U-shape around the article, each driver including a pivotable pushing plate arranged to engage an article to be wrapped as the driver is moved through the folding tube, and a permanent magnet, Which is mounted on the driver, for freely holding the pushing plate in a predetermined position during feed of an article through the folding tube; and means associated with the guide rails adjacent the reversing sec tions of the conveyor chain for reversing the drivers as the pivots on the conveyor chain of the said rods pass around the reversing sections.

8. A wrapping machine comprising a base frame; a horizontal table which is mounted on the base frame and on which articles to be wrapped are fed into the machine; a folding tube mounted in a horizontal disposition on the base frame above the said table; an endless conveyor chain which runs around two reversing wheels carried by the base frame and has a horizontal straight section disposed below and adjacent to the aforesaid table, each re- 6 versing Wheel forming a reversing section of the conveyor chain; means for circulating the conveyor chain around the reversing wheels; guide rails which are fixed to the base frame alongside the conveyor chain and are of hysteresis loop form with the ends of the hysteresis loop adjacent the said reversing sections; a number of drivers guided on said guide rails for movement therealong, at least one rod pivotally coupling each driver to the conveyor chain, each driver being arranged to move through the folding tube to push an article to be wrapped and a wrapper through the tube so that the wrapper is folded into U-shape around the article, each driver including a pivotable pushing plate arranged to engage an article to be Wrapped as the driver is moved through the folding tube, and a permanent magnet, which is mounted on the driver, for freely holding the pushing plate in a predetermined position during feed of an article through the folding tube; and switches, each constituted by a tongue, at the ends of the hysteresis loop form rails for reversing the drivers as the pivots on the conveyor chain of the said rods pass around the reversing sections of the conveyor chain.

References Cited UNITED STATES PATENTS 2,817,933 12/1957 Bell et al. 53233 X 2,980,038 4/1961 Royer 198-24 X 2,999,345 9/1961 Chalmers et a1. 53230 TRAVIS S. MCGEHEE, Primary Examiner. R. L. FARRIS, Assistant Examiner.

Claims

1. A WRAPPING MACHINE COMPRISING A BASE FRAME; A FOLDING TUBE MOUNTED ON THE BASE FRAME; AN ENDLESS CONVEYOR CHAIN WHICH RUNS AROUND REVERSING WHEELS CARRIED BY THE BASE FRAME, EACH REVERSING WHEEL FORMING A REVERSING SECTION OF THE CONVEYOR CHAIN; MEANS FOR CIRCULATING THE CONVEYOR CHAIN AROUND THE REVERSING WHEELS; GUIDE RAILS FIXED TO THE BASE FRAME ALONGSIDE THE CONVERYOR CHAIN AND DEFINING A PATH CONSTITUTED BY AN UPPER TRACK AND A LOWER TRACK WITH INTERSECTING PORTIONS; A NUMBER OF DRIVERS GUIDED ON SAID GUIDE RAILS FOR MOVEMENT THEREALONG, AT LEAST ONE ROD PIVOTALLY COUPLING EACH DRIVER TO THE CONVEYOR CHAIN, EACH DRIVER BEING ARRANGED TO MOVE THROUGH THE FOLDING TUBE TO PUSH AN ARTICLE TO BE WRAPPED AND A WRAPPER THROUGH THE TUBE SO THAT THE WRAPPER IS FOLDED INTO U-SHAPED AROUNG THE ARTICLE; AND MEANS ASSOCIATED WITH THE GUIDE RAILS ADJACENT THE REVERSING SECTIONS OF THE CONVEYOR CHAIN FOR SWITCHING THE DRIVERS FROM ONE TRACK TO THE OTHER AND REVERSING THEIR DIRECTION OF TRAVEL AS THE PIVOTS ON THE CONVEYOR CHAIN OF THE SAID RODS PASS AROUND THE REVERSING SECTIONS.