US3115085A

US3115085A - Packaging machine

Info

Publication number: US3115085A
Application number: US151501A
Authority: US
Inventors: Bilt Pieter Arnoldus Van De
Original assignee: Metaverpa NV
Current assignee: Metaverpa NV
Priority date: 1960-11-15
Filing date: 1961-11-10
Publication date: 1963-12-24
Anticipated expiration: 1980-12-24

Description

Dec. 24, 1963 A P. A. VAN DE BILT PACKAGING MACHINE Filed NOV. 10, 1961 10 Sheets-Sheet 1 INVENTOR P/E me 14k/V0L 00s V/M/M 5/1. 7

BY I/MMM ATTORNEY Dec. 24, 1963 P. A. VAN DE BILT PACKAGING MACHINE l0 Sheets-Sheet 2 Filed Nov. 10, 1961 INVENTOR P1575? Jew/.00.: MM 0: 0/47 BY 2W #M ATTORNEY P. A. VAN DE BILT PACKAGING MACHINE Dec. 24, 1963 10 Sheets-Sheet 3 Filed NOV. 10, 1961 INVENTOR PEEK/4mm ow #4/149/53/4 7 ATTORNEY Dec. 24, 1963 P. A. VAN DE BlLT 3,115,085

PACKAGING MACHINE Filed NOV- 10, 1961 10 Sheets-Sheet 4 E a- 8 N s N 14 9 'i flau 5 g E a 3 2 2 2 T 7 j INVENTOR fi/irik Ammo: Vo/v 065/11 ATTORNEY P. A. VAN DE BILT Dec. 24, 1963 PACKAGING MACHINE l0 Sheets-Sheet 5 Filed NOV. lO, 1961 INVENT OR P/ETER AKAMLDMS l mv 056/47 BY M ATTORNEY Dec. 24, 1963 P. A. VAN DE BlLT 3,115,085

PACKAGING MACHINE Filed Nov. 10, 1961 10 Sheets-Sheet 6 FIG. 6

INVENTOR P/ETE'A 4mm 00.: VAN o: 94

BY M

ATTORNEY Dec. 24, 1963 P. A. VAN DE BILT. 3,115,035

PACKAGING MACHINE Filed Nov. 10, 1961 1O Sheets-Sheet 7 A i no r lw llulmw I P/c' TEE An a: 00.3 Z4 0: 8/4 T ATTORNEY INVENTOR Dec. 24, 1963 P. A. VAN DE BILT PACKAGING MACHINE l0 Sheets-Sheet 8 Filed Nov. 10, 1961 INVENTOR P/srz: JENOLDVJ' Km 0: b/Lr BY 3 e/W ATTORNEY Dec. 24, 1963 P. A. VAN DE BILT PACKAGING MACHINE 10 Sheets-Sheet 9 Filed Nov. 10, 1961 INVENTOR P/ETEA 4mm 00s VA/v 0: Bar

ATTORNEY Dec. 24, 1963 P.' A. VAN DE BILT PACKAGING MACHINE 10 Sheets-Sheet 10 Filed NOV. 10, 1961 P/nn Ae/m 00.: K4 0: 5/4 1 BY w ATTORNEY United States Patent 3,115,085 PACKAGING MACHINE Pieter Arnoldus van de Bilt, Bos en Duin, Netherlands,

assignor to N-V. Metaverpa, Maartensdijk, Netherlands,

a corporation of Dutch law Filed Nov. 10, 1961, Ser. No. 151,501 Claims priority, application Netherlands Nov. 15, 1960 4 Claims. (Cl. 100-4) This application is a continuation-in-part of application Serial Numbers 69,491 (filed Nov. 15, 1960) and 1 1 1,073 (filed May 18, 196 1).

The invention relates to a packaging machine by means of which wire or tape is applied around the pack-age due to the fact that a wire passed around the package in a guide is applied around the package by retraction and tightening and the ends are subsequently joined, said machine comprising a worktable with a guide for the package and a stop mechanism with one or more stops, which project slightly inwards relative to the guide, said stop or stops performing a switching operation when a package abuts against it (them), in consequence of which the machine carries out a packaging cycle. A packaging machine of this kind has been described in my copending application Ser. No. 111,073 filed May 18, 1961, and in my Patents Nos. 3,060,839; 3,060,840 and 3,060,841. Further a package controlled mechanism has been proposed in my patent application No. 69,491, filed November 15, 1960. In this older proposal the worktable is fitted with conveyer rollers which extend slightly above the plane of the worktable and are placed somewhat obliquely relative to the feed direction, so that these rollers hold the package against the guide. As soon "as the package encounters a stop, the machine is put into operation, and as the Wire or tape is tightened around the package the latter is pulled away from the stop by the tightening operation, as a result of which this stop is disengaged again, while the machine completes its cycle, after which the further feeding of the package towards the next stop, if any, can take place. This older proposal sometimes involves certain drawbacks. Heavy cases do not always become sufficiently disengaged from the sto with the result that the further feeding is hampered or the case during its further movement displaces the stop mechanism with its side, thus causing the machine to be switched on at an undesirable moment. When the packages are long, they are not always disengaged from a stop that is at a greater distance from the wire.

The object of the invention is to obviate these drawbacks and this object is attained according to the invention by the feature that near the stop mechanism the guide comprises a ledge adapted to be displaced parallel to itself, by means of which the package can be shifted so as to be disengaged from the operative stop. It is thus disengaged from the stop by force. The stops them selves are preferably provided with push-button contacts.

After the tightening of the wire or tape the ends of the latter are joined and the cutting operation takes place. The package thus has to be disengaged from the stop in any case after these treatments (but it may also at an earlier moment). When this has not yet taken place, it has to be brought about by the movable ledge, and the mechanism operating this ledge in that case can be simply included in the operating scheme of the machine in such a way that at the end of each cycle the ledge is displaced when the operative stopand consequently the contact-4s not yet disengaged.

It is, however, advantageous to have the ledge take part in the tightening operation.

in a packaging machine with pneumatic feed, retraction, and tightening of the wire or tape, as described in .r 3,115,085 Patented Dec. 24, 1963 ice the older proposal according to patent application Serial No. 111,073, according to the invention the mechanism operating the ledge may now come into operation as a circuit is closed by a contact responding to a pressure drop in the discharge pipe of the pneumatic retraction mechanism. This pressure drop invariably has the same value, irrespective of the pressure in the supply line, and the drop occurs as soon as the pneumatic mechanism bringing about the retraction is brought to rest at the end of said movement. The ledge thus comes into operation sooner, i.e. during the tightening of the wire the ledge forces the package in the direction of the tightening movement. The tightening is more uniform in this way, for the difference in tension between the two ends of the wire to be joined, caused by the sliding resistance of the package, now becomes smaller, which has a favourable influence on the twist. The mechanism operating the ledge preferably consists of one or more pneumatic cylinders, to which compressed air is supplied via a valve controlled by the contact responding to the pressure drop.

It is desirable for the ledge not to exert pressure on the package during the twisting and cutting operations. This can be ensured according to the invention by means of a contact in the circuit which controls the operating mechanism of the ledge, which contact is broken while the twisting and cutting mechanism is operating. This can be done, for instance, with the contact breaker 29 described in patent application Serial No. 111,073: This contact (and switch respectively) is thus connected in series with the contact controlled by the pressure drop in the discharge pipe of the retraction mechanism.

The ledge is thus able to move, and consequently so is the package, while the twisting and cutting mechanism is still at rest, and moves again as soon as this mechanism has returned to its initial position, which is useful if the package should not yet have become disengaged. In that case the ledge will no longer meet with resistance on the part of the wire and will thus be able to force the package further away.

At the end of each cycle the vacuum in the discharge pipe disappears because the latter becomes the supply pipe, in consequence of which the vacuum contact is broken and the ledge returns to its former position. The ledge itself is stepped, the number of steps being one less than the number of stops or contacts.

The invention will now be explained in greater detail with reference to the drawings.

FIGURE 1 is a top view of the worktable of the machine according (lI'O the invention.

FIGURE 1:: is a vertical cross section of the worktable of the machine of FIGURE 1 with certain parts eliminated.

FIGURES 2 and 3 are bottom views of the stop mechanism with movable ledge to be placed on the worktable, in different positions of said ledge.

FIGURE 4 is a plan of the greater part of *a pack-aging machine, the working surface carrying the packages being omitted and the vertical parts of the guide for the wire being shown in cross section.

FIGURE 5 is a side elevation, certain lateral lining elements being omitted in order to show clearly the interior of the machine.

FIGURE 6 is a cross section along the line VI--VI in FIGURE 4, in which the feeding and tightening mechanism, which due to lack of space is not shown in FIG- URE 4, is also indicated.

FIGURES 7 and 8 are partially cut-away front elevations of the feeding and tightening mechanism of the machine, the tightening mechanism being shown in two different positions.

FIGURES 9 and 10 are diagrams of the pneumatic and electric circuits respectively of the invention.

The machine shown in FIGURE 1 has a worktable 1 with a feeding conveyer 2 and a discharge conveyer 3. At 4 is mounted the wire-guiding frame, and accordingly it is in this place that the wire is applied around the package. In the plane of the worktable conveyer rollers 5 are present, over which the package is adapted to move and which are mounted in a frame 5a (FIG. 1a) which is retracted below the plane of the worktable with the aid of pneumatic cylinder 14a as a wire is applied as described in application Ser. No. 69,491. At 6 a guide is present and at 7 the stop mechanism, situated in line with the guide, with the

stops

8 and 9, Where contacts 10 and 11 respectively are present. These stops with their contacts are movably mounted on a box-shaped body 12; the cont-acts 10 and 1-1 are connected to the machine via the cables 14 and 15 with plugs not shown in the drawing.

FIGURES 2 and 3 show the lower side of the box 12, so that the

stops

8 and 9 are only partly visible. On the lower side of the box two

pneumatic cylinders

16 and 17 are present, to which compressed air is supplied via the

pipes

18 and 19. These cylinders are adapted to press with the

rods

20 and 21 against a ledge 22, which has been placed in the box with inwardly directed arms 23 and 24, said

arms comprising recesses

28 and 29, which are engaged by

arms

30, 31, which are pivotally fastened to the box at 25, 26 and are pivotally connected with each other at 27, in which latter point is fitted a spring 32, the other end of which is connected with the ledge 22. The mechanism last described provides for accurate parallel guidance of the ledge 22. As appears from FIGURES 2 and 3, the ledge is stepped. The package which abuts against the stop 8 and consequently operates the contact 10 puts the machine into operation for the application of a wire around the package. As the ledge is subsequently moved to the position shown in FIGURE 3 the package is disengaged from the stop 8, and after the ledge has returned to its position of rest, the package is able to move past it until it abuts against the stop 9. Here the same cycle is repeated.

The invention will now be explained more fully with reference to FIGURES 4-8 which show the essential parts of the machine when taken in conjunction with the diagrams of FIGURES 9 and 10 which show the pneumatic and the electric circuits. FIGURES 4-1O inclusive are taken from lapplicants copending application Serial No. 111,073, filed May 18, 1961.

The diagram shown in FIGURE 9 comprises the pneumatic circuit with the electromagnetically operated valves and the pneumatically operated switch-over valves, and FIGURE 10 illustrates the electric circuit, so that electromagnetic valves and switches appearing in FIG- URE 10 as well as FIGURE 9 are denoted by identical numbers. The main supply of compressed air takes place via the pipe 40, filter 41, reducing device 42, and oil-spray lubricating device 43. In the FIGURE 9 diagram, the unbroken lines denote those pipes in which the air is compressed and the broken lines those in which no pressure is present in the position of the diagram at the moment. The diagram has been drawn for the position in which the motor 114 feeds the wire W to wire frame 4 with the aid of the rollers 110 and 111 (also see FIGS. 6-8). The motor 114, which is similar to that described in US. Patent No. 1,781,133, therefore receives air via the pipe 44, the branch 45, the valve 46, and the pipe 47. The discharge of air from the motor takes place via the pipe 48 and exhaust opening of the switch-over valve 49.

When the wire W has been passed all around the frame 4, the end of it is gripped by the clamp 113 (see also FIGS. 4 and 6), the operating cylinder 50 of which clamp is shown in the neutral position. This clamp is adapted to pivot in the direction of movement of the wire W, so that the wire gripped by the clamp will tip over said clamp as shown and described in applicants US. Patent No. 3,060,839, in consequence of which the contact 51 in the switch box is closed. The machine is now in its initial position for performing the next complete cycle, and when the starting switch 10 is now closed, which is elfected by a package being fed to the machine and engaging stop 8, the supply of current to the electromagnetic valve 53 is brought about, in consequence of which this v-alves switches over and the pipe 54 receives compressed air. By this means the valve 49 is switched over via 55, but so is the valve 56, in consequence of which the pipe 57 receives compressed air from the main pipe 44, which pipe leads to the cylinder 50 of the clamp 113, in consequence of which said clamp is closed and holds the end of the Wire, while at the same time from the pipe 57 a branch may lead to a number of cylinders 116 for opening the guide for the wire in the frame 4.

The switch over of the valve 49 has resulted in that the exhaust pipe 48 has now received compressed air from the main pipe 44, but the motor 114 is not yet at once able to reverse its direction of rotation, since compressed air is still present in the pipe 47. The pressure produced in the pipe 57 by the switch over of the valve 56 now acts via the pipe 58 on the valve 46, which, however, does not switch over until the pipes 59 and 60 have been suificiently exhausted via valve 49, when the pipe 47 begins to exhaust, so that the pressure in the pipe 48 begins to predominate, and the motor 114 reverses its direction of rotation, which reversal is used to draw the wire tighter about the package. At the end of this movement the pressure in the outlet pipe 47 will fall, and this fall of the pressure is measured by the plunger 61, which is loaded by the spring 62 and which closes the contact 63 when the fall of the pressure is sufficient. This closing of the contact 63 causes the excitation of the electromagnetic valve 64, in consequence of which the latter switches over and from the main pipe 44 compressed air is supplied to the pipe 65, which leads to the cylinder 117 of the tightening mechanism 117.

Tightening mechanism 117' as shown in FIGS. 6-8 includes a main lever 109 pivotally connected at 109 to frame 1. Guide 108 is mounted on main lever 109 and, as can be seen, the wire W is passed through guide 108 to feeding rollers 110 and 111. A slot is provided in main lever 109 in which clamp 119 is movably mounted between

guide members

112, 112. A double-armed lever is pivotally mounted in the slot and includes one arm 120' engaging a recess in clamp 119 while the other arm 120" engages a recess in an extension 118. Guide member 112 and the inner end of the slot form a channel in which extension 118 is reciprocably movable and an abutment against which arm 120 abuts when extension 118 is moved to the right in FIG. 7. Rod 118 and extension 118' are pivotally connected to a secondary lever 209 which is pivotally connected to main lever 109 at 210. A spring 211 is connected between secondary lever 210 and plate 212 on which cylinder 117 is mounted. Spring 211 maintains tightening mechanism 117 in a normally inoperative position. Extension '118 has a head element 118" which abuts against lever 109 as shown in FIGS. 6 and 7 to maintain

levers

109 and 209 in connection with each other when the tightening mechanism is in the inoperative position.

The wire is now tightened firmly about the package, while the pressure in the cylinder 117 rises, and this rise of the pressure is measured via the pipe 66 by the measuring device 67, which is equipped with a plunger sliding against spring tension.

Pipes

18 and 19 are branched off from pipe 66 to

cylinders

17 and 16 of ledge 22 to operate same to move the package in the direction of tightening movement. When a given pressure has been reached, this measuring device closes the switch 68, which is provided with a magnet coil which has been incorporated in such a way in the electric circuit that through the mechanical closing of the switch 68 the latter is held in its closed position. The closing of the switch '68 results in the excitation of the electromagnetic valve 69, in consequence of which compressed air is supplied from the main pipe 44 via the pipes 70 and 71 to the switch-over valve 72. Thus the

pipes

73 and 74 receive compressed air, with the result that the cylinder 75 for controlling the clamp 75 which is located between feeding rollers 110, 111 and the twisting mechanism 123' (see FIG. 4) and which is to hold the tightened end of the wire is brought into op eration, 'while further the cylinder 123 for moving the twisting mechanism 123 is operated.

Twisting mechanism 123' as shown in FIGS. 4 and is formed by a twisting pinion 221, which is located in a block 222 adapted to move on the guiding tracks 401. Block 222 can be reciprocably moved by cylinder 123 which is coupled to block 222 by rod 224. By a movement to the left of block 222 in FIGURE 5, the juxtaposed ends of the wire are fed to the twisting pinion 221 which is rotated by gear wheel 127'. A toothed rack 126 is driven by pneumatic cylinder 127 which engages gear wheel 127' to rotate same. Toothed rack 126 is equipped with an abutting surface 132 which operates switch 128 and an extension 133 which operates switch box 131, while rod 224 has a cross arm 123" which cooperates with

switches

129 and 130.

Owing to the displacement of the block 222 by the cylinder 1'23 and rod 224, the contact 129 is broken and the contact 130 closed by arm 123". The breaking of the contact 129 involves at the same time the neutralization of the excitation of the electromagnetic valve 76 and of the electromagnetic valve 64. The adjustment of the valve 76 breaks the connection between the switch-over valves 46 and 49, which at this moment is still of no account. By the neutralization of the excitation of the valve 64, the pipes 65, 66 and the cylinder 117 can be exhausted, in consequence of which the tightening mechanism 117 and ledge 22 return to their initial positions under the influence of

springs

211 and 32 respectively.

Owing to the closing of the contact 130, the electromagnetic valve 77 is excited, in consequence of which via the pipe 78 compressed air is supplied to the valve 49, which switches over owing to this, while at the same time via the pipe 79 compressed air is supplied to the switchover valve 86, owing to which the latter switches over and compressed air can now be supplied from the main pipe to the cylinder 127, which serves to operate the twisting mechanism 123 through gear 127' by displacing the toothed rack 126. This displacement of the toothed rack 126 results in the breaking of the contact 81 and the closing of the contact 82 in the switch box 131 by the disengagement of extension 133 therewith, and at the end of its movement in the closing of the contact 128 by abutting surface 132. The breaking of the contact 81 results in the neutralization of the excitation of the switch 68, in consequence of which the latter opens again, and this in turn results in reversal of the electromagnetic valve 69, by which means the pipes leading to the

valves

49 and 80 are exhausted. At first the closing of the contact 82 has no consequence at all. The closing of the contact 82 merely assures that a part of the circuit of the electromagnetic valve 83 is closed, which valve, however, cannot yet be excited, because the contact 84 in the switch box 115, which is controlled by the clamp 113, is still open.

At the end of the movement of the toothed rack 126, the contact 128 is closed, and this energizes the electromagnetic valve 85, in consequence of which the valve 80 is reversed by supply of compressed air from the main pipe and the drive of the toothed rack is reversed. During the return movement of the toothed rack 126, the cutting mechanism 134, 135 for the wires is operated, owing to which the clamp 113 is released and thus closes the contact 84. This inturn results in the closing of the circuit of the electromagnetic valve 83, owing to which the latter switches over and compressed air is supplied from the main pipe 44 to the pipes 86 and 87. The pipe 87 leads to the pneumatic cylinder 50 for operating the clamp 113, in consequence of which the latter opens and is forced away until the cut-off end of the wire can drop out. The pressure in the pipe 86 results in switch over of the valve 72, owing to which the twisting mechanism returns to its initial positionand the cylinder 75 also releases the clamp 75' holding the wire. When the toothed rack and the twisting mechanism have returned to their initial position, the

contacts

81 and 129 are closed again and the contact 82 is broken, while the valve 76 is reexcited, so that via the previously reversed valve 49 compressed air is supplied to the valve 46, which reverses, so that via the main pipe compressed air is supplied again to the pipe 47, which actuates the motor 114 for feeding wire again. As soon as the end of the latter reaches the clamp 113, the contact 51 is closed again and the next cycle has become dependent on the operation of the starting switch 11 to repeat the same cycle.

The diagram finally includes the pipe 88, by means of which compressed air is constantly supplied to the cylinder 89, with which the pressure roller 111 is kept under pressure. Further, a switch 90 is present, which scans the feed of the wire and breaks the contact as soon as the wire has run out, so that the valve 76 after the return of the twisting mechanism cannot be excited, which prevents the air motor feeding an insufficient remnant of the wire supply into the machine. The current supply is controlled by the connection to the supply mains at 91, while at 92 is shown a reversing switch, by means of which the machine can be returned to its initial position when in the middle of a cycle something has gone wrong and the machine has come to a standstill.

It is further observed that the clamp 113 is returned to the initial position by the opening of the contact 82 at the end of the path traversed by the toothed rack during its return movement. The electromagnetic valve 83 then returns to its initial position, in consequence of which the cylinder 50 is exhausted again and is able to return to its neutral position.

What I claim is:

1. A packaging machine having a worktable, a wireguiding frame of loop formation extending vertically above said worktable dividing the worktable into a feedin section and a feed-out section, means to feed wire through a guide channel of the guiding frame, a clamp to hold the leading end of the wire at the end of the guiding channel of the frame, means to withdraw the wire from the frame and around a package on the worktable, means to tie the ends of the wire, said work table having a guide along the length of the feed-in section for guiding the packages, a stop mechanism disposed adjacent said frame, said stop mechanism having at least one stop means which projects slightly inwards relative to the guide so as to be in the path of a package, switch means located adjacent said stop means and being adapted to be actuated by an incoming package, said switch means, when so actuated, being adapted to initiate operation of the wire-feed means and the means to withdraw the wire from the frame, ledge means located adjacent said stop means and being normally positioned to one side of the stop means so that a package first engages said stop means, means to reciprocate said ledge means, and means operatively connected to said withdrawing means when the wire is withdrawn from said frame to operate the ledge-reciprocating means to push the package laterally on said worktable away from said stop means so that the package can continue to move away from the frame on the feed-out section of the worktable.

2. A packaging machine according to claim 1 wherein said stop mechanism includes an additional stop means spaced from said first-mentioned stop means along said feed-out section of the worktable, and additional switch means located adjacent said additional stop means and being adapted to be actuated by the package after moving away from said first-mentioned stop means so that the operation cycle effected by said first-mentioned switch means is repeated.

3. A packaging machine having a work-table, a wireguiding frame of loop formation extending vertically above said worktable dividing the worktable into a feedin section and a feed-out section, means to feed wire from a supply through a guide channel of the guiding frame, a clamp to hold the leading end of the wire at the end of the guiding channel of the frame, means to withdraw the wire from the frame and around a package on the worktable, means to tie the ends of the wire, a twisting and cutting mechanism to connect the ends of the wire and to sever the formed loop of wire from the supply, said worktable having a guide along the length of the feed-in section for guiding the packages, a stop mechanism disposed adjacent said frame, said stop mechanism having at least one stop means which projects slightly inwards relative to the guides so as to be in the path of a package, switch means located adjacent said stop means and being adapted to be actuated by an incoming package, said switch means, when so actuated, being adapted to initiate operation of the wire-feed means, the means to withdraw the wire from the frame and the twisting and cutting mechanism, ledge means located adjacent said stop means and being normally positioned to one side of the stop means so that a package first engages said stop means, means to reciprocate said ledge means, means operatively connected to said withdrawing means when the wire is withdrawn from said frame to operate the ledge-reciprocating means to push the package in the direction of tensioning of the wire away from said stop means, and means operatively connected between said twisting and cutting mechanism and said ledge-reciprocating means under the control of said twisting and cutting mechanism to prevent said ledge-reciprocating means from operating said ledge means while said twisting and cutting mechanism is operating.

4. A packaging machine having a worktable, a wireguiding frame of loop formation extending vertically above said worktable dividing the worktable into a feedin section and a feed-out section, means to feed wire through a guide channel of the guiding frame, a clamp to hold the leading end of the wire at the end of the guiding channel of the frame, pneumatic means to withdraw the wire from the frame and around a package on the worktable, means to tie the ends of the wire, said worktable having a guide along the length of the feed-in section of the worktable, a stop mechanism located on the feed-out section of the wire-guiding frame, said stop mechanism having a plurality of stop means which project slightly inwardly relative to said guide so as to be in the path of a package, switch means located adjacent each of said stop means and being adapted to be actuated by an incoming package, said switch means, when so actuated, being adapted to initiate operation of the wirefeed means and the pneumatic means to withdraw the wire from the frame, a retractable ledge located adjacent the stop means and being normally positioned to one side of the stop means so that a package first engages the stop means, means to reciprocate the ledge, and additional switch means operated by a pressure drop in said pneumatic means when the wire is withdrawn from said frame to operate the ledge-reciprocating means to push the package laterally on said worktable away from said stop means so that the package can continue to move away from the frame on the feed-out section of the worktable.

References Cited in the file of this patent UNITED STATES PATENTS 2,334,736 Willcox Nov. 23, 1943 2,619,027 Sykes Nov. 25, 1952 2,630,750 Eberle Mar. 10, 1953 2,768,756 Horman Oct. 30, 1956 2,942,715 Miller June 28, 1960