US2901992A - Pedestal mounted portable bag closing machine - Google Patents

Description

Sept. 1, 1959 F. LUTZ ETAL PEDESTAL MOUNTED PORTABLE BAG CLOSING MACHINE Filed May 14, 1957 6 Sheets-Sheet 1 Sept. 1, 1959 F. Lu-Tz ETAL PEDESTAL MOUNTED PORTABLE BAG CLOSING MACHINE 6 Sheets-Sheet 2,

Filed May 14, 1957 Sept. 1, 1959 F, u'rz ETAL 7 2,901,992

PEDESTAL MOUNTED PORTABLE BAG CLOSING MACHINE Filed May 14, 1957 6 Sheets-Sheet 3 FIG.6

F. LUTZ ETAL 2,901,992

PEDESTAL MOUNTED PORTABLE BAG CLOSING MACHINE Sept. 1, 1959 6 Sheets-Sheet 4 Filed May 14, 1957 FIG.-8

l l c li Sept. 1, 1959 u'rz EI'AL 2,901,992

PEDESTAL MOUNTED PORTABLE BAG CLOSING MACHINE Fild May 14, 1957 6 Sheets-Sheet 5 Sept. 1, 1959 I F. LUTZ EI'AL 2,901,992

' PEDESTAL MOUNTED PORTABLE BAG CLOSING MACHINE Filed may 14. 1957 s Sheets-Sheet 6 FIG.

United States Patent PEDESTAL MOUNTED PORTABLE BAG CLOSING MACHINE Friedrich Lutz, Stuttgart-Degeriock, and Hermann Daniel, Stuttgart, Germany, assignors to Union Special Maschineufabrik G.m.b.H., Stuttgart, Germany Application May 14, 1957, Serial No. 659,008

Claims priority, application Germany May 30, 1956 Claims. (Cl. 112- 11) This invention relates to bag closing machines and in particular to portable electric bag closing machines of the character disclosed in applicants pending application Serial No. 535,316 filed September 20, 1955. As disclosed in said application, the portable bag closing machine is of light weight and adapted to be held in the hand of the operator as it is used to close filled bags by a sewing operation. In dealing with large and heavy filled bags the operator carries the machine from bag to bag and moves the machine across the pinched together mouth of the bag to form the desired closure.

In factories and warehouses it is frequently found necessary to close not only large and heavy bags, but also large numbers of small bags. It is of particular importance in forming a closure seam for small bags, which may contain sugar for example, that the seam be made very accurately and neatly. This is not always an easy thing to achieve by a machine held in the hand. For this special type of work there has heretofore been provided relatively heavy, stationary bag closing sewing machines capable of providing a neat and accurate sewn closure for small, filled bags formed of cloth or paper.

A primary object of the present invention has been to adapt the portable electric bag closing machine of the above-mentioned pending application for the production of the desired accurate and neat sewn closures of small cloth and paper bags after they have been filled. In this way the same machine is adapted for the double purpose of closing large and heavy bags, requiring the movement of the machine by hand across the tops of such bags, and of closing small bags which are sewn to better advantage when the machine is held stationary and the bags .are moved by hand.

In accordance with the invention the electric motor of the machine disclosed in applicants pending application, which motor is connected directly and rigidly with a flange on the sewing head, is held stationary and retained in fixed position by two clamping jaws which grip the body of the electric motor and serve to hold the same firmly. Vibration damping or isolating strips or elements are interposed between the clamping jaws and the housing of the electric motor to prevent transmission of the vibrations from the motor and sewing head to the supporting table. The arrangement employed in accordance with the invention is such, moreover, that the extent to which the jaws may be brought together in clamping the electric motor is limited in a way to prevent squeezing of the vibration damping strips or elements to .such an extent that their vibration isolating property is destroyed or seriously reduced. Preferably one of the jaws is held stationary while suitable screw means serves to shift the other clamping jaw toward the stationary jaw. When the screw means is released or backed-off the movable clamping jaw is urged outwardly away from the stationary clamping jaw under spring action. The stationary jaw is formed integral with a supporting collar ror thelike adapted to be shifted along afixed column 2,901,992 Patented Sept. 1, 1959 and locked in any desired set position on the column, depending upon the height of the bags to be closed. Thls column is preferably carried by a table which serves to support small bags at the proper elevation for most convenient handling by the operator in forming the desired closure. When the motor is held by the clamping jaws in the manner explained, the machine is adapted for use in forming neat and accurate sewn closures on small bags.

Control over the delivery of electric current to the motor is preferably exercised from a foot treadle so that the hands of the operator are free to be used in manipulating the filled bags in the course of forming the closure. For this purpose the delivery of current to the motor may be controlled by a foot operated switch or, if desired, suitable mechanical connections may be provided from a foot treadle to the switch button or plunger provided at the top of the handle of the portable sewing machine disclosed in applicants above-mentioned pending application. When a foot operated switch is employed to control the delivery of current to the motor, this is connected on one side to a suitable source of current and on the other side in series with the push button or plunger switch provided on the handle of the machine. This push button switch on the handle is, for this purpose, adapted to be retained in its depressed or on position so that the actual control over the delivery of current to the motor is provided directly by the foot operated switch. A spring catch or latch fastened to the handle of the portable sewing unit is arranged to cooperate with a shoulder on the push button or plunger to retain the latter in its depressed or on position. This catch spring is of arched construction and arranged to have its free end cooperate,

under suitable spring force, with the rear edge of the push button and with the top of the handle. The arrangement is such that when the push button is depressed the free end of the spring will automatically swing over the shoulder on the push button to retain it in its depressed position. When it is desired to release the push button the operator simply urges the spring, by his thumb or finger, off of the shoulder on the push button so that the spring provided within the handle for urging the switch into its open position will force the push button outwardly. This catch spring arrangement may be used advantageously even when the machine is being held and guided by the hand of the operator in closing large filled bags since it relieves the operator of the necessity of exerting a downward pressure on the push button switch throughout a bag closing operation. When the closure has been completed the catch spring may be readily shifted, in the manner explained, to release the push button.

In lieu of controlling the motor by means of a foot operated switch, as explained above, a mechanical connection may be provided from a foot treadle to a member mounted on the handle of the sewing unit which is adapted to urge the switch on the handle into its on posntion. For this pun-pose there is provided on the handle a double-armed rocking lever, one arm of which is connected by means of a chain, a rod or a Bowden cable with the foot treadle while the other arm cooperates with the push button of the switch to close the same. This second arm is provided with a nose which is arranged to engage the top of the handle of the sewing unit and limit further rocking movement of the double-armed lever so that its move- 'ment is suflicient only to depress the switch button to close the sewing unit which, in accordance with the disclosure 3 of applicants pending application, serve to provide a means of attachment of a suspending strap. A single screw passing through the downwardly extending arms of the bracket and through the handle serves effectively to retain the bracketed the sewing iiiiit. spring surrounding the pivot pin for the double arnied lever continuously urges the lever into its ,fofifpos ition. v lever is rocked against the action i this spring by the mechanical connections from the foot treadle. rocklng lever and its supporting bracket may be retaifie'd on the sewing unit even when the machine is held and guided by the hand in the course of sewing large andheavy bags in the manner disclosed in said pending application. To make use of the machine in this wayit is simply necessary to detach the chain, rod or Bowden from the one arm of the rocking lever then release the clamping aws to permit removal of the sewing advantage derived from leaving the rocking lever on the handle of the unit at this time is that the switch button operating arm of the lever extends some distance forwardly of the switch button where it may be more readily engaged by the thumb or finger of the operator and may be actuated with less force due to the area leverage provided. When it is desired to restore the sewinguhitto its stationary position on the column it is sirnply necessary to reinsert it in the clamping jaws, tighten the latter and then connect the chain or rod or Bowdencab-le to the arm of the rocking lever, Thus, the use of the machine alternately in the two different ways may be very readily and simply accomplished.

The sewing unit may be readily adjusted along the supporting column to place the stitch forming devices at the appropriate elevation above the table top to close bags of any desired height. If a Bowden cable connection is provided from the foot treadle to the rocking lever, no change is required in this connection as the unit is raised or lowered on the column. However, if a chain connection is used from the treadle to the rocking lever, the effective length of the chain must be varied to correspond with the selected operating height of the machine. This can very simply be done by providing a hook on the rocking lever which is adapted to be hooked into any one of the links of the chain to give it the desired eifective length.

Other objects, features and advantages of the invention will appear from the detailed description which will now be given of several illustrative embodiments in conjunction with the accompanying drawings, in which:

Fig. 1 is a side elevational view of the portable sewing unit mounted on a column carried by a supporting table equipped with 'a treadle actuated electric switch;

Fig. 2 is a plan view, on a reduced scale, showing the sewing unit and the supporting column;

Fig. 3 is an elevational view of the supporting column and the clamping means for retaining the sewing unit;

Fig. 4 is an elevational view of the clamp-ing unit;

Fig. 5 is a detail view illustrating the push button switch on the handle of the sewing unit and the spring element for retaining the switch in its on position;

Fig. 6 is a view similar to Fig. 1 but illustrates a modification embodying a chain connection from the foot treadle to a rocking lever on the sewing unit for operating the push button switch thereof; I Fig. 7 is an enlarged detail view of a portion of the sewing unit of Fig. 6, illustrating details of the rocking lever and its connections;

Fig. 8 is a plan view of the parts illustrated in Fig. 7;

Fig. 9 is an elevational view similar to Fig. 1 illustratj ing'a modified arrangement in "which a Bowden cable is used to connect the foot treadle with the rocking lever;

. Fig lt) is'an enlarged detail'vie'w showing a portion of the sewing unit of Fig. 9'and the connections between the Bowden cable and the rocking lever; and v Fig. 11 is a plan view of the parts shown in Fig. 10. Turning now to the drawings, there shown a sewing head or machine 1 having rigidly and directly connected therewith an electric driving motor 2. This motor is preferably detachably connected with the sewing machine by a bayonet type connection of the character disclosed in the above-mentioned pending application. The combined sewing machine and motor unit is supported in a fixed position by means of a. bracket 3 having a. collarlike portion mounted on a vertically disposed column 4. The bracket is slidable along the column to any desired position of adjustment and may be secured in adjusted position by means of a wing screw 11. At its lower end the column 4 is received by a socket 5 having a base 6 which is secured by screws or the like to the top 7 of a supporting table structure. A set-screw 5a (Fig. 6) may be provided to retain the column 4 firmly in the socket 5. Bracket 3 has two clamping jaws 8 and 9 which can be opened and closed by manipulation of a wing nut 10 which cooperates with a bolt secured to and extending laterally from the bracket. Clamping jaw 9 may suitably be formed integral with the bracket while the clamping jaw 8 is arranged for pivotal movement about a pin 39 carried by the bracket, as best shown in Figs. 3 and 4. On the shank of the bolt which receives the wing nut 10 there is mounted, between the two clamping jaws, a compression spring 40 which urges the clamping jaw 8 away from the jaw 9. Thus, upon turning the wing nut 10 to carry it outwardly along the bolt the spring 40 will shift the jaw away from jaw 9 and thereby enable the insertion or removal of the motor 2. Upon turning of the wing nut 10 in the opposite direction the jaw 8 will be forced toward the jaw 9 to clamp the motor.

The clamping jaws 8 and 9 are provided with strips or pads 12 of vibration damping or isolating material. These strips or pads may suitably be formed of rubber. They are the only parts of the clamp which actually en'- gage the motor and thus serve to isolate vibrations created in the motor and sewing machine and prevent their transmission to the bracket 3. To guard against undue compression of the strips or pads 12 upon the turning of the wing nut 10 to clamp the motor, and thus destroy the effectiveness of the strips or pads 12 as vibration isolating means, a ring or sleeve 41 is provided around the bolt which carries the wing nut 10 and this ring or sleeve is disposed within the spring 40 and between vertical surfaces of the two jaws. It thus limits the extent to which the jaws may be forced together. In this way the transmission of any possible vibrations of the sewing machine and motor to the table top 7 is effectively eliminated.

Current may be supplied to the electric motor 2 by means of a cable 14 connected at its upper end with the motor through a portion of a handle 13, which in the closing of large filled bags may be used to carry and guide the sewing machine and motor unit by the hand of the operator. Interposed in the connections from the cable 14 to the motor is a switch 15 which may be manually depressed by the operator. This switch has an operating button or plunger which is provided with a shoulder 17 (Fig. 5) which, when the plunger is depressed to a position in which the switch is in its on position, will be substantially flush with the top of the handle. A spring 16 of arcuate form is secured to the end of the handle 13 and so constructed that its free end is biased "toward the button or plunger 15 and also downwardly toward the top of the handle. Thearrangement is such that when the button 15 is depressed to close the switch the end of the spring will ride over the shoulder 17 and retain the button in its depressed position. The free end of the spring latch16 is urged downwardly witha suitable force against the top of the handle 13 to'ov'ercome the force of the spring provided in the switch and thus retain the latter'in its on or closed position when the latch is en -gaged over the shoulder 17. When-it is desired to repressure by the thumb or finger,*and the spring within the switch itself will then lift the button or plunger and open the switch.

Whenever the bag closing machine is held stationary by the clamping jaws 8 and 9 and related parts, in accordance with the invention, it is not practicable to control the delivery of current to the motor by manual operation of the switch button 15 on the handle, as is normally done when the machine is held in and guided by the hand of the operator. This is because both hands of the operator are normally required in the stationary use of the machine to push the small filled bags across the top of the table 7 to bring about the desired closure seam. Accordingly, under these conditions, it is desirable to provide for control over the operation of the motor by suitable connections from a foot treadle. This, as has been explained, can be accomplished by an electric foot switch in series with the switch 15 or by a mechanical device from a foot treadle for operating the button or plunger of switch 15. In Fig. 1 there is shown apreferred embodiment for the control of the operation of the motor 2 by a foot switch 20. A cable 21 having a plug adapted for insertion in a socket 21a, connected with a source of supply of electric current, serves to deliver the current to the switch 20. When the operator depresses the treadle plate a the switch 20 is closed and delivers the current through cable 14 to the handle of the sewing machine and motor unit. It will be understood that at this time the operator will have depressed the button or plunger 15, to close the switch in the handle and cause it to be held closed by the action of latch 16, so that the delivery of current to the motor is actually controlled by the switch 20. When the machine is being used in this fashion the switch 15 will be held in closed position by the latch 16 for an indefinite period of time.

Referring now to Fig. 6, there is shown a difierent embodiment of the invention in which a suitable form of mechanical connection is provided from a foot treadle to the switch carried by the handle 13 of the machine. The connections for this purpose comprise a double- armed rocking lever 24, 26, the arm 24 of which is connected by a chain 22 with a treadle 23. As will be apparent, depression of the treadle 23 will rock the arm 24 downwardly and this in turn will cause the arm 26 to rock downwardly and depress the button or plunger 15 which is beneath it. In this way the switch will be forced into its on position. In order to prevent injury to the switch or the operating button or plunger 15 by the application of too strong a force to the foot treadle 23, the rocking arm 26 is provided with an extension 27 (Fig. 7) which comes in contact with the top of the handle 13 when the switch 15 has been properly closed. This prevents any further downward movement of the double- armed rock lever 24, 26. The rock lever is carried by a pin 34 (Figs. 7 and 8) supported in a U-shaped bracket 28 having the free ends of its legs provided with downward extensions 29 one of which lies against one side of the handle 13 and the other of which lies against the opposite side of the handle. The handle is provided with laterally extending projections 31 on each of its sides and the extensions 29 fit between these projections to assist in retaining the bracket 28 in fixed position. A screw 32 passing through the extensions 29 and through an aligned opening in the handle serves to lock the parts in place. One of the extensions 29 is provided with screw threads in its opening to cooperate with threads on the screw for this purpose. A torsion spring 33, surrounding the pin 34 forming the pivot for the rock member 24, 2s, urges this rock member in a counterclockwise direction (Fig. 7) and thus permits the push button or plunger 15 to rise to its ofi position.

When the sewing machine and motor unit is lifted or lowered from one position of adjustment to another along the column 4, it is necessary to increase or decrease the effective length of the chain 22. This is readily accomplished by the provision of a book on the arm 24 of the rock member, the lower end of this hook being 6 adapted for connection with one or another of the links of the chain to provide the desired efiective length.

In Fig. 9 there is shown another form of mechanical connection from the foot treadle to the rock member. This involves the provision of a Bowden cable 35 the lower end of which is secured by a fitting 37 to a bracket forming part of the treadle construction. The upper end of the cable is held by a bracket 35a carried by the handle 13. A treadle 36 when depressed will draw downwardly on the wire forming the inner member or core of the Bowden cable and the latter through its connection with an arm 24a of the rock member, similar to member 24, 26 of the embodiment previously described, will bring about operation of the switch in the handle 13 in the same manner. The form of the rock memher in the Fig. 9 embodiment may be substantially the same as in the Fig. 6 embodiment and the operation of the switch button or plunger 15 may be brought about in the same manner. However, the arm 24a of the rock member may extend forwardly of the handle 13, as shown in Figs. 10 and 11, instead of rearwardly as in the case of arm 24, since the Bowden cable may readily bend around the motor 2 and clamping jaw 8. A spring 38 surrounding the core or operating element of the Bowden cable adjacent its upper end, and compressed between the bracket 25a and a lateral extension of the arm 24a, serves to restore the latter to its inactive position upon release of pressure on the treadle 36. An advantage of this arrangement is that no change is required in the connection of the Bowden cable 35 at either end as the sewing machine and motor unit is raised or lowered to adjust the machine for operation on bags of different height. The flexibility of the cable 35 is such as to make possible such variation in height of the unit.

Several difierent arrangements have been described above for controlling the operation of the portable sewing machine from a foot treadle when the machine is mounted in a fixed or stationary position in relation to a table top to facilitate the accurate and neat formation of closure seams for small filled bags. It will be understood that various changes may be made in the construction and arrangement of the various parts for achieving this purpose. The invention herein disclosed makes possible the use of a light weight, portable sewing machine in either of two ways, i.e., held and guided by the hand of the operator in the closing of relatively large and heavy bags which remain in fixed position on the floor and the closing of relatively small bags which are rather easily advanced along a table top by the operator when the machine is held in a fixed or stationary position.

What is claimed is:

l. A bag closing apparatus which comprises a unit having a sewing machine and a directly and rigidly connected electric motor, said motor being constantly connected with said machine for driving the latter through a positive drive, means for supporting said unit comprising a supporting column, a bracket adjustable along said column, and means for securing said bracket in adjusted position on said column, said bracket having a plurality of clamping jaws adapted to grip said motor to retain the same and thereby support said unit.

2. A bag closing apparatus of the character set forth in claim 1 in which compressible vibration isolating means is interposed between said clamping jaws and said motor, and in which means are provided to limit the relative movement of said clamp-ing jaws into clamping position.

3. A bag closing apparatus of the character set forth in claim 1 in which spring means is provided to urge said clamping jaws into inactive position, and positively acting mechanical means is provided to urge said clamping jaws into active gripping position.

-4. In a bag closing apparatus of the character set forth in claim 1, means for delivering current to said motor, an electric switch for controlling the supply of current to said motor, and treadle means carried by said supporting means for operating said switch to control the starting and stopping of said sewing machine.

5. A bag closing apparatus of the character set forth in claim 4 in which a second electric switch is provided in series with said switch operated by said treadle means for controlling the supply of current to said motor, said second switch being mounted on said motor and arranged for manual operation by the operator.

6. A bag closing apparatus of the character set forth in claim 4 in which said unit is provided with a carrying handle, a manually operable second electric switch carried by said handle and arranged in series with said switch operated by said treadle, and a spring latch on said handle arranged to lock said second switch in its closed position upon manual operation thereof.

7. A bag closing apparatus of the character set forth in claim 4 in which said electric switch is mounted on said unit and in which mechanical connections are provided from said treadle means for operating said switch.

8. A bag closing apparatus of the character set forth in claim 7 in which said unit is provided with a carrying handle, said switch being carried by said handle, said mechanical connections comprising a rock member mounted on said handle arranged to engage the switch to operate the same and means for transmitting movement from said treadle to said rock member.

9. A bag closing apparatus of the character set forth in claim 8 in which said rock member and handle are provided with cooperating stops for limiting the switch operating movement of said rock member.

l0.- A bag closing apparatus which comprises a lightweight, portable unit having a sewing machine and a directly and rigidly connected electric driving motor in constantdriving relation to said machine through positive drive connections, a handle secured to said unit by Which the same may be held and guided by the hand of the operator in closing bags, supporting means having a readily releasable clamp for retaining said unit in fixed position, a depressible switch operating button on said handle for controlling delivery of current to said motor, a rock member on said handle having an arm arranged to depress said button upon rocking of said member, and a treadle carried by said supporting means and connected with said rock member for operating the latter.

References Cited in the file of this patent UNITED STATES PATENTS 1,427,532 Hambrock Aug. 29, 19 22 1,761,752 Scott June 3, 1930 2,474,331 Sauer June 28, 1949 2,484,495 Fischbein Oct. 11, 1949 2,660,140 Attwood Nov. 24, 1953

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