US3420201A - Eared container feeding apparatus - Google Patents

Description

R. A. HEISLER Jan. 7, 1969 EARED CONTAINER FEEDING APPARATUS Sheet Filed July 18, 1967 INVENTOR. RAYMOND A. HEISLER Jan. 7, 1969 R. A. HEISLER EARED CONTAINER FEEDING APPARATUS Sheet Filed July 18, 1967 INVENTOR. RAYMOND A. HEISLER BY 22% AGENT INVENTOR.

R. A. HEISLER EARED CONTAINER FEEDING APPARATUS 5 f O 3 a a e m a W W 5 FM. 2F a h a o I ZKM j Q o i Eff 5 w a w o wM v g I MW w lllffl. e D F a W 0 L O O G Jan. 7, 1969 Filed July 18, 1967 BQAYMOND A. HE ISLE R @m AGE N T Jan. 7, 1969- R. A. HEISLER 3,420,201

EARED CONTAINER FEEDING APPARATUS riled July 18, 1967 Sheet 4 of 5 0b Ix ae 2 a INVENTOR.

BAYMOND A. HEISLER AGENT 7, 1969 R. A. HEISLER 3,420,201

BAKED CONTAINER FEEDING APPARATUS Filed July 18, 1967 Sheet 5 of 5 INVENTOR. IWWMOND A.HE$LER BY AGENT United States Patent 3,420,201 EARED CONTAINER FEEDlNG APPARATUS Raymond A. Heisler, 657 Dakota Trail, Franklin Lakes, NJ. 07417 Filed July 18, 1967, Ser. No. 654,208 U.S. Cl. 113-113 16 Claims Int. Cl. B21d 43/26 ABSTRACT OF THE DISCLOSURE A container feeding apparatus adapted for semi-automatic and hand feeding of eared containers to and through a bail-inserting machine and which includes a gravity-type roller conveyor having a selected slop through the machine. A pair of ramps are mounted on the machine and are positioned so as to engage the ears of the advancing container and provide a cam surface for lifting the container by its ears from the inclined conveyor and at the end of the cam surface a beveled end forms a receiving notch for retaining the cars at a determined bail-inserting position. After the bail is inserted a stop arm in the way of each of the ears of the container is moved to release the ears so that the container drops onto the conveyor for transporting from the inserting machine. A detecting means may be provided to insure that an unbailed container is properly positioned in the apparatus before insertion of the bail.

BACKGROUND OF THE INVENTION Field of the invention This invention relates generally to the class of Metal Working and in particular to the subclass of assembling and disassembling aparatus with a magazine supply. The field of art of this invention may also apply to the general class of wire working and in particular to the subclass of applying wire in which subclass is found many bail-applying mechanisms.

Description of the prior art Bail-applying or bail-inserting mechanism is well known in the art and in particular reference is made to U.S. Patent 2,623,274 to Henchert issued Dec. 30, 1952, and U.S. Patent 3,241,578 issued to myself on Mar. 22, 1966. In these and like patents there are indicated or shown bailapplying mechanisms in which an eared container is brought in the way of a bail-applying or a combined bailforming and inserting mechanism by which is inserted the ends of a wire bail into the ears of the container. Insofar as is known the mechanisms shown in this art and other bail-applying mechanisms used in the field do not provide for a semi-automatic or hand-fed apparatus in which the manipulation of the container by the operator to align the ears and to place the container on a conveyor so as to feed the eared container to the machine is the only necessary function of the operator. In the present state of the mechanical art of packaging and particularly in the apparatus for packaging and shipping paint and the like in eared containers such as one and five gallon cans, there are many operations that require short-run operations and in which the use of completely automatic equipment is neither necessary nor in many cases desired.

The present invention contemplates the semi-automatic operation of a bail-applying mechanism of the type generally shown in my U.S. patent as referred to above. This mechanism is changed and/ or altered to incorporate or permit the use of an inclined gravity-type conveyor upon which the service operator of the mechanism places an eared container with the ears disposed in a predetermined alignment which, to be further shown and described, is transverse to the movement of the container on the conveyor. After positioning and releasing the container on the conveyor the eared container moves forwardly and downwardly to a determined location whereat it is stopped with each of its ears in a recess and where a sensing means detects the receipt of the container. A bail is formed and inserted in the ears of the container after which the bailed container is released onto the conveyor for transport to a discharge end for packaging or other operations.

SUMMARY OF THE INVENTION This invention pertains to apparatus for container feeding to mechanism for attaching bails to eared containers in which there is provided an inclined gravity-feed conveyor and the like and having a determined slope so that eared oriented containers are fed with their ears in and to a predetermined position in a bail-applying mechanism. A pair of slides or ramps are mounted on the mechanism so that each ramp is adapted to engage an ear of an advancing container and with its upper surface at a lesser slope than the conveyor lift the container by its ears from the conveyor. At the end of the slide an ear-receiving recess is provided so that the ears of the container are moved into a determined position for a bail to be applied such as in the manner as shown in my U.S. Patent 3,241,578 issued Mar. 22, 1966.

There is preferably provided in conjunction with this container feeding conveyor and ear-engaging ramps, a stop means movable to and in front of the receiving recess portion of the ramp so that the ears of the container are nested in a particular position. With each of the ears received into the recesses, a sensing device or signal circuit is actuated to signal that the ears of the container are in a desired or selected position after which the bail-applying mechanism is actuated to insert the ends of the bail into each of the ears of the container.

It is an object, therefore, of this invention to provide a container feeding apparatus adapted to receive each eared container as delivered to it by hand or by other means and to advance these containers into a bail-applying mechanism whereby the ears of the advancing container are brought in the way of ramps which engage the ears to lift the container from the conveyor, each ear proceeding finally to a receiving notch. The container, with its ears in the notches, is suspended above the feeding apparatus and in this selected position a bail is inserted into the ears of the container after which the ears of the bailed container are released from the notches so that the container is delivered to the feeding apparatus for transport from the bail-applying mechanism.

It is a further object of this invention to provide a gravity-type conveyor adapted to receive and transport an eared container to and through a bail-applying mechanism, and a pair of ramps each disposed on a side of the conveyor and positioned so as to engage the ear of the advancing container and lift the container by its cars from the conveyor and at the end of the ramp to receive the ear in a retaining notch whereupon a sensing means detects the ear and with the container in the desired position the bailapplying mechanism is actuated, the bail is applied to the container whereupon the ears of the bailed container are released from the notches and the container drops on the conveyor for transport to other operations or discharge.

INTENT OF THE DISCLOSURE Although the following disclosure olfered for public dissemination is detailed to ensure adequacy and aid in understanding of the invention, this is not intended to prejudice that purpose of a patent which is to cover each new inventive concept therein no matter how it may later be disguised by variations in form or additions of further improvements. The claims at the end hereof are intended as the chief aid toward this purpose, as it is these that meet the requirement of pointing out the improvements and combinations in which the inventive concepts are found.

There has been chosen a specific embodiment of a gravity-feeding conveyor and ear-engaging ramps adapted for use therewith and showing a preferred means for feeding the eared containers to a bail-applying mechanism. This specific embodiment is contemplated for use with one of two sensing and activating systems which have been chosen for the purposes of illustration and description of the eared container feeding apparatus which is shown in the accompanying drawings forming a part of the specification wherein:

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 represents a front view of a bail-applying mechanism and looking at the discharge side and showing in particular the relative position of the gravity-feeding conveyor of the eared container feeding apparatus;

FIG. 2 represents in an enlarged scale an isometric view, partially fragmentary, showing the arrangement of the conveyor and the ramps on which the ears of the container are fed into bail-applying position;

FIG. 3 represents in an enlarged view the relationship of one of the ramps to the curling-die of the bail-applying apparatus;

FIG. 4 represents a somewhat fragmentary side view partly in section and showing the relationship of the conveyor and the bail-applying apparatus, and with a container and ear shown in phantom outline, the view taken on the line 4-4 of FIG. 2;

FIG. 5 represents a diagrammatic representation of the container and the gravity-feed conveyor and with the container approaching an ear ramp;

FIG. 6 represents a diagrammatic showing of the container feeding apparatus of FIG. 5 and with the container having progressed down the conveyor until the ear of the container is about to engage the ramp;

FIG. 7 represents a diagrammatic showing of the container feeding apparatus of FIG. 5 with the container having advanced forwardly into a receiving notch position whereby bails are inserted in the ears of the container;

FIG. 8 represents a fragmentary isometric view of an alternate conveyor construction of the conveyor of FIG. 2 but with a roller omitted therefrom;

FIG. 9 represents a schematic circuit diagram showing an electrical sensing and actuating circuit for the combination of the container feeding apparatus and the bail-applying mechanism, and

FIG. 10 represents a schematic circuit diagram showing a pneumatic sensing and actuating circuit for the combination of the container feeding apparatus and the bailapplying mechanism.

DESCRIPTION OF THE PREFERRED EMBODIMENT 2 Referring now in particular to the drawings wherein like numbers refer to like members throughout the several figures and in particular to FIGS. 1, 2, 3 and 4, it is to be noted that the bail-applying mechanism generally indicated as in FIG. 1 is described in detail in my US. Patent 3,241,578 issued March 22, 1966. The automatic feeding and orienting of the eared containers to this bailapplying mechanism is by an orienting conveyor. In the present invention this conveyor is replaced by a roller conveyor 25, which conveyor is of the gravity-feed type and is sloped at a determined incline so that containers, when placed thereon, roll forwardly at a determined speed and without the necessity of impetus on the part' of the operator. Referring in paticular to FIG. 4, it is to be noted that in relationship to a base 27, the conveyor 25 is sloped at an angle of approximately six and one-half degrees to the horizontal; however, this angle is merely a matter of selection to suit the particular conditions under which the container and conveyor are caused to operate.

As seen in FIGS. 2, 3 and 4 there is no container orienting means provided by the conveyor 25 so it is required that each container 30 be oriented with its ears 31 and 32 disposed at substantially right angles to the path of the convey-or so that as the container moves down the conveyor the ears are transverse to the motion. As the container approaches the bail-applying mechanism 2.0 each ear of the container 30 is brought in the way of one of two like ramp members 34 and 36. Each ramp is disposed at a predetermined distance from the general path of the conveyor and its inward facing surface acts as a guide means for insuring that the container enters and is centered between the two ramp members. As the eared container moves forwardly and downwardly on the conveyor the ears 31 and 32 are brought in the way of the upper ramp surfaces, which surfaces may be sloped at an angle of about one-half or one degree. The forward motion of the container and small slope of the ramp surfaces causes the ears to slide forwardly on these surfaces until they engage a downwardly angled slope 38 and 40, at which slope the ear drops into the notch formed by one of these slopes and by one of two cover stop arms 42 and 44 which also are actuated to cover one of the bail-end forming dies 46 as described in my above-identified patent. Slopes 38 and 40, as shown, are about thirty degrees to the horizontal but may be more or less as selected.

Referring now to FIGS. 5, 6 and 7 in which there is a diagrammatic showing of the operation of the eared container as it is fed into the bail-applying mechanism and in particular to the container 30 as it is advanced leftwardly and downwardly on the conveyor 25. As viewed in FIG. 5, the container is approaching the ramp 36 and stop arm 44- but has not yet come in the way of the ramp 36.

Referring next to FIG. 6, it is to be noted that the container 30 has advanced downwardly and leftwardly on conveyor 25 and that the car 32 is ready to engage the upper surface of ramp 36 and, although not shown, a like ear 31 diametrically disposed on the container is also at the same time engaging the upper surface of ramp 34 mounted on the opposite side of the conveyor 25.

Referring next to FIG. 7, it is to be noted that the forward motion of the container 30 and the slight slope of the upper surface of the ramp has caused the ear 32 to carry it fowardly on the surface of the ramp 36 so that it, the ear, has slid leftwardly until it reaches the angle portion 40 whereupon the ear 32 drops into the notch formed by the angle portion 49 and the stop arm 44. It is to be noted that the container at this point is suspended above the rollers of the conveyor 25 and in this position the container is free to swing and the ear is centered in the notch. It is at this position that the bail is inserted into the cars 31 and 32 and since the ears are made of a predetermined size and, as the arm 44 and slope 40' are sized and spaced for this particularly sized ear, the ear is substantially in a precise position and the aperture in the ear is in a predetermined location, as for example, within plus or minus one-sixteenth of an inch or less of a nominal selected location.

Referring next to FIG. 8, there is shown an alternate conveyor to the conveyor of FIG. 2. In this alternate conveyor a roller is removed to insure the free swinging of the container by its ears. Between rollers 47 and 48 a roller is absent and in this space between the rollers there is mounted a pair of slide or support plates 49 and 50. These plates are attached to conveyor side members 51 and 52 and when mounted the plates have their facing edges formed with an arcuate shape so as to provide a portion of a circular recess slightly larger than the diameter of the container. The outer portions of the plates extend from roller 47 to roller 48 so as to support the lower rim of the container until the upstream edge of the container is over the contoured void between the plates and the ears ofthe container are each in the notch between the slope and stop arm. The upper surfaces of plates 49 and 50 are about in the plane of the upper or carrying surfaces of rollers 47 and 48 and provide a smooth transporting medium for tthe container as it moves downwardly on the conveyor.

Referring next to FIG. 9, there is shown an electrical signal or actuating circuit diagram in which is provided a means for detecting the ears of the container when they are in the notches and in the position as shown in FIG. 7. In this position a sensing signal detects the presence of the container and actuates the bail-applying mechanism. As seen in this circuit diagram, a three-phase source of power which may be two hundred twenty volts is indicated as being supplied by conductors 60, 61 and 62, which lines are fused as by fuses 64, 65 and 66. From the fuses the lines lead to a motor 68, which motor is started by means of an manual switch indicated in phantom outline 70. The motor once started, of course, continues to operate to rotate a clutch-connected crank shaft when the clutch is engaged. The clutch is not shown and may be an electric clutch operated as by a solenoid 72, which solenoid is actuated as a consequence of the receiving of a container 30 with the ears in the notch position so that an electrical contact is established through the ears 31 and 32 on each side of the container and to and through the container to a relay 74.

As the pail 30 enters the signal system a pail position switch 76 is caused to be closed. This switch is preferably positioned so as to engage the container at or near its bottom position. Ears 31 and 32 meanwhile come to rest on contacts 78 and 79, each of which is mounted in or on the notches 40 and 38 of the ramp members and are positioned so as to engage an ear when the ear is in the notch. These contacts in this circuit are supplied with low voltage which in the present instance is furnished by transformer 80 providing sixteen volts. The container 30 as it completes the circuit energizes relay 74 which closes the double pole contacts 82 and 83. The set of contacts 82 when closed forms a holding circuit with the pail position switch 76 as the control switch.

At the same time that contacts 82 are closed the contacts 83 are closed so that the coil 84 of the off-delay timing relay is energized. Contacts 86 as they are closed cause clutch solenoid 72 to be energized and the bail-applying mechanism to be cycled to insert a bail into the ears of the container. The normally closed contacts 90 remain closed for a determined interval of time which in the present instance is one-fifth of a second which is the pulse time needed to release the clutch and insure the proper engagement and disengagement of the clutch.

The circuit or system will stay in this state with all relays energized until such time as the container leaves the bail-applying position at which time the holding circuit to the double pole relay 74 is broken, thus allowing another cycle to start. This circuit or system allows the bail machine to operate in a continuous manner when the supply of containers to the bail-applying mechanism is at the same rate as the cycle of operation of the mechanism. This condition requires that an adequate supply of containers be maintained and fed to the conveyor 25 and that the bailing machine have a proper positioning of the stopping point of bail-applying operation cycle. With a determination of the desired feeding rate of the containers to and through the conveyor 25 the clutch solenoid energizing time may be adjusted with the delay timer cycle energizing time so that any pulsing of the solenoid 72 is eliminated.

To provide a manual start or overide of the container detecting circuit there is shown a manual start switch 88, normally open, which when closed provides an actuation of the circuit as in the manner when a container is in position. Of course, switch 76 is also closed but this merely requires a manipulation of the sensing finger or arm 91.

Referring finally to FIG. 10 and a pneumatic signaling and clutch energizing system, there is shown a three-phase feed line system with conductors 92, 93 and 94 carrying an electric current of, as for example, two hundred twenty volts to and through fuses 96, 97 and 98 to a manual switch 109 indicated in phantom outline and by which motor 182 is started. The motor once started, of course, operates to rotate a clutch-connected crank shaft 104. A pivoted arm 1% is actuated to cause the clutch to engage or disengage.

The ramp members 34 and 36 have pneumatic passageways 116 and 112 formed therein with one end terminating at the slope 38 or 40 and with the other end connected to pneumatic lines 114 and 116 which extend to T-memher or connection 118. This T-member is connected by line 120 to a booster v122 which is supplied through line 124 by pressurized air from a source not shown. From booster 122 a line 126 leads to a cylinder 128 which actuates the clutch release arm 106.

The booster valve indicated as 122 is of a commercial design and application and is used as a means for permitting an adjusted pressure of, for example, forty to fifty pounds p.s.i. to be fed to the booster through line 124. A bleed feed in the booster allows a small volume of air to flow through line 120 and to and through lines 114 and 1.16. When the outlets from passageways 110 and 112 are closed the booster is cycled to allow a large amount of pressurized air to flow through the line 126 to cylinder 128 and to actuate this cylinder.

The passageways 110 and 112 may terminate at other locations instead of terminating on the sloped surfaces 38 and 40 where they are closed by the circumferential portion of the ears. For example, the lines 114 and 116 may be formed to bring their outlets against the outer surfaces of the ears. The outlets may also be positioned so as to be shut by surfaces of the container. The location of the outlets is a matter of selection, it being only important that the container be sensed when it is positioned and ready for the applying of a bail.

OPERATION OF THE PNEUMATIC SIGNAL Pressurized air from line 124 enters booster 122 and moves through line 120, T-member 118 and lines 114 and 116 and discharges from passageways 110 and 112. When ears 31 and 32 are received in the notches they block the flow of air from the passageways 110 and 112 whence flow stops and the flow in line 120 is stopped booster 122 is actuated for line 126 to become filled with pressurized air at the line pressure to cause cylinder 128 to cycle and actuate arm 106 and the clutch. A spring return in the cylinder 128 is provided for the returning of the cylinder to its normal position when passageways 110 and 112 are opened by the movement of ears 31 and 32 from in the way of the passageways.

METHOD OF FEEDING EARED CONTAINERS The feeding of eared containers in a semi-automatic or hand feeding manner and actuating a bail-applying mechanism by the detecting of the presence of an cared container includes the steps of: placing an eared container on a gravity-feed conveyor and the like; orienting the ears of the container so that they are substantially transverse to the path of the conveyor; releasing the container to travel to and through a bail-applying mechanism; bringing the ears of the container in the way of ramps 01 cams so as to lift the container by its cars from the conveyor; restraining or engaging the ears so that they are in a precise position in a notch or the like; detecting the presence of a container so as to actuate the bail-applying mechanism, and after applying the bail, releasing the now bailed container onto the conveyor for transport from the machine.

Terms such as in, out, righ left, up, down, normal and the like as applied to the eared container feeding apparatus are shown and described in conjunction with the drawings. These terms are used merely for the purposes of description and do not necessarily apply to a particular position in which the feeding apparatus may be constructed or used.

The conception of the eared container feeding apparatus and the method of feeding the eared containers and its many applications is not limited to the examples abovedescribed but departures therefrom may be made Within the scope of the accompanying claims and protection is sought to the broadest extent the prior art allows.

What is claimed is:

1. A container feeding apparatus for receiving and transporting oriented eared containers to and through a bail-applying mechanism and the like, the feeding apparatus including: (1) a conveyor adapted to receive and transport eared containers, the conveyor disposed at a slope in relation to a horizontal plane and so that with the containers oriented in the manner received, said containers are transported forwardly and downwardly to and through a bail-applying mechanism and the like; (2) a ramp member disposed on each side of the conveyor, said ramp member disposed so as to be adjacent the path of the sides of the container as it moves forwardly and downwardly on the conveyor; (3) an ear engaging sliding surface provided on the top of each ramp, said top surface at a lesser slope to the horizontal plane than the conveyor and disposed so as to engage the ear of the container when the ears are substantially transverse of the container path 'whereby as the container advances the container is lifted by its cars from the conveyor; (4) an earreceiving means at the termination of each of the sliding surfaces, the receiving means sized and positioned to engage and retain the ear at a determined position; (5) means for detecting the presence of an ear in the earreceiving means, and (6) means for releasing the container from the ear-receiving means so that the container is returned to the conveyor for transport from the conveyor.

2. A container feeding apparatus as in claim 1 in which the conveyor is a gravity-type conveyor.

3. A container feeding apparatus as in claim 2 in which the gravity-type conveyor includes a plurality of like-sized rollers carried in a close spaced array by a pair of side members, and in which one of the rollers is absent at a selected position in the conveyor, a pair of side plates each mounted on a side member and having a portion providing a sliding surface from one roller to the next roller in the space of the absent roller, and said plates when mounted also having their facing edges contoured to provide a void sized to provide a passageway for a portion of the bottom of the container.

4. A container feeding apparatus as in claim 3 in which the contoured void portions of the facing edges of the plates are arcuate portions providing a circular recess portion slightly larger than the bottom of the container.

5. A container feeding apparatus as in claim 1 in which the ramp member is attached to the bail-applying mechanism with the inner faces spaced so as to slidably engage and guide the container as it moves into and between the ramp members.

6. A container feeding apparatus as in claim 1 in which the ear-receiving means includes a downwardly-angled sloped downstream end portion of the ear engaging sliding surface of the ramp member and a cover stop arm of the bail-applying mechanism, the cover stop arm forming a receiving notch with the angled slope.

7. A container feeding apparatus as in claim 6 in which the downwardly angled slope is about thirty degrees from the horizontal and the means for releasing the ear is the moving of the cover stop arm from in the way of the angled slope.

8. A container feeding apparatus as in claim 1 in which the means for detecting the presence of an ear in each of the ear-receiving means is an electrical signaling circuit in which an electrical contact is adapted to conductively engage the ear when said ear is in the receiving means, the contacts forming a part of the detecting circuit which is conductively actuated when the container is in position with each contact engaging an ear and with the container between the ears providing the ear-to-ear conductor portion.

9. A container feeding apparatus as in claim 8 in which the detecting circuit is a low voltage circuit and in which there is additionally a pail position switch also in the detecting and holding circuit, said switch adapted to engage and be activated by a lower portion of the positioned container.

ltl. A container feeding apparatus as in claim 1 in which the means for detecting the presence of an ear in each of the ear-receiving means is a pneumatic signaling system in which a pair of pneumatic passageways are each adapted to have its terminating end closed by the presence of an ear, said passageways forming a portion of a pneumatic circuit supplied by pressurized air and adapted to actuate a cylinder and the like when the ears of a container have closed the flow of air from the terminating ends of the pneumatic passageways.

11. A container feeding apparatus as in claim 10 in which the pneumatic circuit includes a booster valve adapted to be cycled when the terminating ends of the pneumatic passageways are closed and at this end of the cycle the booster is adapted to feed a full flow of pressurized air to a cylinder to actuate a clutch and the like in the bail-applying mechanism.

12. A container feeding apparatus as in claim 1 in which the means for detecting the presence of an ear in each of the ear-receiving means is at least one pneumatic passageway adapted to actuate a pneumatic signaling system when the terminating end of the pneumatic passageway is closed, said passageway adapted to terminate adjacent and be closed by a side wall portion of the container when said container is in position in the ear-receiving means.

13. A container feeding apparatus as in claim 1 in which the conveyor is a gravity-type conveyor, and in which each of the ramp members are attached to the bailapplying mechanism with their inner faces spaced so as to slidably engage and guide the container as it moves into and between the ramp members, the ramp having its downstream end portion formed with a downwardlyangled sloped portion and with a cover stop arm of the bail-applying mechanism forming with said sloped portion an ear-receiving notch.

14. The method of feeding eared containers to a bailapplying mechanism and in a semi-automatic manner and actuating the bail-applying mechanism by the detecting of the presence of an eared container, said method including the steps of: (a) placing an eared container on a gravity-feed conveyor and the like; (b) orienting the ears of the container so that they are in a plane generally transverse to the path of the conveyor; v(c) releasing the container to travel to and through a bail-applying mechanism; (d) bringing the ears of the container in the way of ramps adapted to engage the ears and to lift the container by its ears from the conveyor; (e) engaging the ears of the container so that they are in a precise position in an ear-receiving notch; f) detecting the presence of a container so as to actuate the bail-applying mechanism, and after the actuation of the mechanism, and (g) releasing the ears of the container from the ear-receiving notches to release the container onto the conveyor for transport to a discharge point.

15. The method of feeding eared containers as in claim 14 in which the detecting of the presence of a container is an electrical circuit in which contacts are arranged to engage the ears of the container when in a bail-applying References Cited UNITED STATES PATENTS 12/1952 Henchert 14093 3/1966 Heisler 14093 RICHARD J. HERBST, Primary Examiner.

U.S. Cl. X.R.

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