US2845888A - Detector means for can head crimping machine - Google Patents

Description

Aug. 5, 1958 J. D, WINTERS ETAL 2,845,888

DETECTOR MEANS FOR CAN HEAD CR-IMPING MACHINE Filed Nov. 23. 1951 s Sheets-Sheet 1 Aug. 5, 1958 ,Filed Nov. 23, 1951 J. D. WINTERS ET AL 2,845,888

DETECTOR MEANS FOR CAN HEAD CRIMPING MACHINE 5 Sheets-Sheet 2 57 27 ,25 5 24 23 2o 32 L 30 141? 5&2

d2 1 Inga/2W4;

Aug. 5, 1958 J. D. WINTERS ETAL DETECTOR MEANS FOR CAN HEAD CRIMPING MACHINE 5 Sheets-Sheet 3 Filed Nov. 23, 1951 Lia/W Aug. 5, 1958 D. WINTERS E'rAL 45,888

DETECTOR MEANS FOR CAN HEAD CRIMPING MACHINE Filed' Nov. 23, 1951 5 Sheets-Sheet 4 #4 z mmz/ g- 1958 J. D. WINTERS ET AL 2,845,888

DETECTOR MEANS FOR CAN HEAD CRIMPING MACHINE Filed NOV. 23, 1951 5 Sheets-Sheet 5 Jug/01507114 i I [Mime fMzadww Jflwwh trite DETECTOR MEANS FOR CAN HEAD CRIMPING MACHINE Application November 23, 1951, Serial No. 257,779

3 Claims. (Cl. 113-7) This invention relates to a machine for crimping and sealing cans and particularly to a machine for crimping and sealing small metal cans forming part of an electrolytic capacitor assembly and detector means, located in advance of the crimping means, for removing said metal cans which are not properly filled. While the machine forming the subject matter of this application is useful for other purposes, it has been particularly designed for crimping and sealing small cans having an upwardly extending centrally disposed wire or red from the center thereof with the sealing and crimping occurring at the top of the can. The can forming part of an electrolytic capacitor, which is operated upon by this machine and sealed thereby is fully disclosed in the copending application of Oliver S. Aikman, Serial No. 248,899, filed September 29, 1951, now Patent No. 2,744,217.

Crimping machines for operating upon conventional cans in which, for example, food is packed are well known and widely used. As a rule, the metal forming the can has several layers folded over to provide a tight and strong mechanical joint. The machine to be hereinafter described difiers fro-m such prior crimping machines in the manner in which the crimping is obtained. Additionally, the machine to be described has suitable automatic means for ejecting the finished articles and for ensuring proper operation of the machine. The cans operated upon are much smaller than any conventional cans and, in practice, the cans operated upon are so tiny that they only hold several drops of water.

For a more complete understanding of the invention, reference will now be made to the drawings wherein:

Figure l is a front view of a complete machine embodying the present invention;

Figure 2 is a detail on line 2-2 of Figure l;

Figure 3 is a sectional detail on broken line 33 of Figure 2;

Figure 4 is a sectional view along broken line 4-4 of Figure 1;

Figure 5 is a detail partly in section with bearing cap and plate removed and certain crimping dies in section to show the crimping action, the parts being in position for the start of crimping;

Figure 5A is a detail of the crimping dies after crimping has taken place;

Figure 6 is a sectional detail along broken line 6--6 of. Figure 2 showing a detecting means for defective units;

Figure 7 is an enlarged view of certain parts of Figure6, showing the action of the mechanism when a defective unit is present and is to be rejected by the machine;

Figure 8 is a perspective detail of the control valve in connection with pneumatic discharge of defective units;

Figure 9 is a sectional detail of the detector pin in place on a can;

Figure 10 is a section of the completed crimped can produced by the machine.

The machine comprises a base 10 which is adapted rates Patent 0 to rest upon the floor or on a suitable massive support and which extends upwardly the full height of the machine for the purpose of supporting the various mechanical elements thereof. It is understood that base 10 may be constructed of a number of different parts, the various parts being bolted together in conventional fashion and being of suitable material, such as cast iron or steel as require-d. Extending upwardly from the part of the base near the floor is standard 11 carrying at the top thereof bed 12. Bed 12 carries on the top thereof inner and outer heater rings 14 and 15 resiliently supported by spring means 16, one of such spring supporting means being shown in detail in Figure 6. .A number of such spring-supporting means is provided, the individual spring-supporting means being angularly spaced along the bed so as to support the heater rings and urge the same resiliently upwardly as seen in Figure 6. The resilient supporting means may include suitable nuts and bolts for adjusting the spring pressure urging the heater rings upwardly.

The heater rings may be of any suitable material such as iron or aluminum and each ring carries within it one or more electric heating elements 17 of any suitable type. The heater rings may be suitably constructed and split at proper places for permitting the disposition of the heater elements within the rings. Suitable electricallc'onnections for energizing the heating element within the heater rings are provided so thatthe heater rings may be heated to a predetermined temperature and maintained at such temperature.

Carried by bed 12 are annular support bearings 20, these bearings being disposed outside of heater ring 15. As is shown in Figure 3, support bearing20 carries the rim of index table 22. Index table 22 is rotatively supported at the center by stepped bearing member 23. Cover plate 24 is disposed over the central portion of index table 22, cover plate 24 being spring pressed downwardly by spring 25 coiled around king bolt 27 threaded to the center of bed 12 and carrying nuts 28 for compressing the spring.

Index table 22 and heater rings 14 and 15 are. so designed that during normal operation, the heater rings will be pressed against the bottom smooth faces of the index table for the purpose of heating the same.

Instead of having the heating rings stationary with respect to the index table-it is understood, of course, that the index table during the operation of the-machine is intermittently moved-it is possible to have heating means integral with or attached to the index table and movable therewith for the purpose of heating the same. The index table structure itself, together with its bearing support and the like, is conventional in various types of mechanisms.

Index table 22 has its edge machined to provide a predetermined number of index teeth 32 (see Fig. .2), these teeth being suitably shaped sothat theindex table may be moved in one direction only by conventional dog and lever means. Indextable 22 also has 'recess 33 and can receiving die 34 for each recess corresponding to'each index tooth 32. Radially aligned with each die recess 33 and seating die 34 is air-valve-ejecting pin 35, these pins being inwardly disposed with respect'to the die recesses.

The means for intermittently indexing table 22 in a clockwise direction, as seen in Fig. 2, is conventional. Thus the entire machine is provided with fiy-wheel 40 and crank shaft 41 suitably journaled' inthe upper portion of the frame of the machine. Single revolution clutch means controlled by a pedal near the floor is also provided in such machines. Crank shaft 41 carries crank. disc 42 at the end thereof, this discbeing provided 59 will extend upwardly beyond the washer.

with crank pin 43. Cooperating with crank pin 43 is crank 44 whose bottom end engages arm 45 of bell crank 46 suitably journaled at 47. Bell crank 46 has arm 48 pivotally coupled to slide 49, suitably mounted for movement upon the bed of the machine. Slide 49 carries detent dog 50, which is spring pressed by leaf spring 51, to engage the teeth of the index table.

The bed of the machine also carries pivoted lever 53 whose rounded end 54 cooperates with locking dog 55. Lever 53 is operated by slide 49 through bolt 53a so that locking dog 55 is moved to an unlocking position when slide 49 is moved for indexing the table.

For convenience now, a description of the article upon which the machine works will now be given. This article comprises can 57 of ductile metal, such as silver, for example. Can 57 has an outwardly disposed offset 58 and the blank itself continues upwardly as seen in Fig. 10 in the form of cylindrical mouth portion 59. As fed to the die plate, the complete unit upon which the machine works comprises the can as shown in Fig. 10 with an electrode assembly. Thus, can 57 has a quantity of electrolyte 60 and electrode assembly 62. Electrode assembly 62 includes wire or pin 63 extending upwardly as seen in Fig. 10, the bottom of this pin being carried by metal disc 64. Below metal disc 64 is annular washer 65 resting upon offset 58 of the can. Above disc 64 is additional annular washer 66. The details of the washer and electrode structure are not important for the understanding of the invention disclosed herein. As is evident in Fig. 10, when the electrode assembly is positioned within can 57, prior to crimping, the upper portion of mouth Pin 63 will be high enough to extend substantially beyond the mouth of the can.

As seen in Fig. 10, the finished article has edge por; tion 68 of the can crimped inwardly to form a generally toroidal portion extending downwardly against top washer 66 and maintaining the system of Washers under compression. Each seating die 34 in the index table is adapted to be supplied with one of the units, these units being disposed within the die recess so that overhang 58 rests upon the top surface of the die and maintaines the cup vertically in position. The feeding station for supplying units to the index table may be at any desired spot in front of the machine, this being toward the bottom of the index table, as seen in Fig. 2, and preferably somewhat toward the right.

The means for performing the crimping will now be described. Thus, referring to Fig. l, crank shaft 41 is operatively connected through crank 70 to ram 71. Ram 71 slides vertically between guides 72 and 73 carried by the frame of the machine. Guides 72 and 73 carry stationary cam plates 74 and 75 having cam surfaces 76 and 77 as shown. Ram 71 carries bell crank 79 at one side thereof. This bell crank is pivoted at 80 and is provided with cam roller 81 for cooperation with stationary cam surface 76.

Ram 71 also carries bell crank 83 pivotally mounted at 84 and having cam roller 85 for cooperation with stationary cam surface 77. Bell crank 79 has arm 86 with rounded hammer portion 86a at the end thereof. Bell crank 83 has arm 87 terminating in fork 88 whose bottom is rounded (see Fig. 5), the fork being disposed below rounded head 86a of crank 79. It will be noted that crank 79 has its pivot axis 80 somewhat higher above the index table than pivot 84 of crank 83. Correspondingly, cam surface 76 for actuating bell crank 79 is also larger and has the top raised somewhat higher than cam surface 77.

Ram 71 carries within it a crimping die assembly shown in detail in Figs. 5 and 5A, this die assembly being disposed within the interior of the ram and normally being covered by a suitable cover plate at the front of the ram. Thus, the die assembly consists of barrel 90 of generally cylindrical shape, the bottom of 4 which has an outwardly extending flange portion 91 engaging the bottom of the ram block. Barrel 90 has bore 92 axially thereof within which is disposed sleeve 93. Sleeve 93 has annular cut-out 94 near the bottom thereof and in this cut-out there is positioned coil spring 95. Block 97 forms an extension of barrel 90 and encloses enlarged bottom 98 of sleeve 93. It will be noted from Fig. 5 that coil spring lies between shoulders formed by end 98 of sleeve 93 on the one hand and shoulder 100 from a small extension of the bottom of barrel 90. Block 97 is long enough so that chamber 101 formed thereby will permit some vertical reciprocation of sleeve 93. It will be noted that in the position shown in Fig. 5 the upper portion of sleeve 93 extends above the top portion of barrel 90.

At the bottom of block 97 is guide block 103 having downwardly depending portion 104, the guide block having the inside finished to provide cylindrical channel 105. As is clearly evident from Fig. 5, cylindrical channel 105, in each index position, is aligned with a seating die 34 previously described. Tightly locked between guide block 103 and block 97 is crimping die 108, this die having an interior cup shape with the bottom curved as shown in Figs. 5 and 5A. Crimping die 108 is securely locked in the lower portion of block 97, the block being recessed as shown to accommodate the crimping die. Crimping die 108 has bore 109 axially thereof. Movable in bore 109 is can stripper rod 110 extending upwardly within sleeve 93 and rigidly locked thereto by set screw 111. Rod 110 cooperates with the rounded bottom of die 108 to direct the flow of metal during crimping. Push rod 112 is slidably mounted within sleeve 93 and extends above sleeve 93 to be engaged for downward movement by rounded end 86a of hell crank 79. The top of sleeve 93 is similarly engaged by fork 88 of hell crank 83.

Push rod 112 is relieved at 113 to accommodate locking pin 114 seating in a drilled opening through sleeve 93. Locking pin 114 cooperates with slot 113 to limit the vertical travel of push rod 112 with respect to sleeve 93.

Within sleeve 93 and around reduced portion 115 of push rod 112 is coil spring 116. Coil spring 116 tends to bias push rod 112 upwardly with respect to sleeve 93. Reduced portion 115 carries pin 117 extending downwardly therefrom and movable within bore 118 of can stripping rod 110 for stripping the cup or can.

At this point a brief description of the actual operation of the various dies for the crimping will now be given. Thus, assuming that a can assembly has reached the crimping station beneath the ram, the ram will move guide block 103 over the neck of the index table seating die. Mouth portion 59 of the can will enter the annular region within crimping die 108 and outside of rod 110. By virtue of the shape of the surface within crimping die 108, the downward pressure of the ram upon the can will cause the edge of the can metal to begin to flow inwardly and curve. When the ram has completed its full downward stroke, the edge of the can will be crimped as shown in Fig. 10. It is understood of course, that changes may be made in the contour of the die and length of stroke to control the amount of flow of the metal. During the crimping movement of the ram, stripper pin 117 will contact pin 63 of the electrode assembly. As the ram begins to withdraw upwardly from the index table, pin 117 is urged downwardly and engages the free end of the pin 63 of the electrode assembly and prevents the complete assembly from following the ram and die up from the index table die. Spring 116 permits the above action without requiring precise timing.

At the same time, sleeve 93 is moved downwardly, thus moving stripper rod 110 so that this rod bears down on the top of the electrode assembly around pin 63 and aids in maintaining the cup and electrode assembly in position in the seating die of the index table. Thus a stripping action for both the entire assembly and for pin 63 is provided upon withdrawal of the ram. It is understood of course, that the .bell cranks for causing the movement of the two strippers are properly timed to accomplish the desired results. This will be more fully described when the general operation of the machine as a whole is described.

Means are provided in advance of the crimping station to detect the presence of a defective can assembly. This detector means is generally movable vertically with the ram. Carried by ram 71 is bracket 130 extending generally parallel to the index table and to the left as seen from the front of the machine (Fig. 1). Bracket 130 carries mounting support block 131 having bore 132 within which is slidably mounted rod 133. Rod 133 is shouldered and has coil spring 134 around reduced portion 135 of rod 133. This reduced portion is threaded at 136 and is provided with stop nut 137 to limit the downward drop of the rod. Rod 133 has secured at the lower end thereof shoulder block 139 carrying guide pin 140 working in recess 141 in block 131.

Shoulder block 139 carries detector pin 144 at the bottom of which is mounted detector head 145. Detector head 145 is shaped so that the head may enter mouth 62a of the can (it is understood of course, that the can blank has not yet been crimped), the bottom of the head resting upon the washers as shown in Fig. 9. Detector head 145 has recess 146 within which pin 63 of the electrode assembly may normally enter when the detector head is dropped down in the detecting position shown in Fig. 6. It may be observed, that in the down position of the detector head as shown in Fig. 6, the ram is in its bottom position. It is understood that spring 134 will permit shoulder block 139 to rise with respect to block 131 during detection.

Shoulder block 139 also carries feeler pin 148, this pin extending down from the shoulder block and being aligned with an air valve ejecting pin 35 when the table is at an index position. Each air valve ejecting pin 35 is mounted in index plate 22 so that the pin is movable vertically. Friction means for retaining pin 35 in any vertical position is provided. Thus, as shown in Fig. 7, index plate 22 has plate 149 bolted thereto, the plate being apertured to permit pin 35 to pass through the same. Index table 22 has recess 151 below plate 149 and within this recess and hugging pin 35 is spring washer 152. Friction of the washer on the pin will tend to maintain pin 35 in any vertical position unless the pin is forcibly moved from such position.

The various clearances of the detector head and feeler pin 148 are so arranged that the detector head engages the top of can assembly to limit the down travel of block 139 at a point where feeler pin 148 will just clear the top of air valve control pin 35. It is understood that pin 35 is normally in its uppermost position, as shown in Fig. 6, for example. In the event that there are no washers in the can or no electrode assembly, then detector head 145 will drop so that feeler pin 148 engages air valve pin 35, pushing it down.

Bed 12 of the machine carries pin 155 vertically disposed in the bed and adapted to rotary movement. Pin 155 is disposed in the portion of the bed (see Fig. 4) below the detector head assembly. Pin 155 carries finger 156, this finger extending into the path of the air valve control fingers 35 as they are moved during the indexing of the table. As shown in Fig. 7, when air valve pin 35 is depressed, because of a defective assembly, pin 35 will remain in its depressed position and the lower portion thereof will engage finger 156 upon the succeeding index movement of the index table.

Pin 155 has the bottom thereof connected to control air valve 157. The outlet of this air valve is connected by hose 158 to pipe 160 extending through the table bed and registering with an opening through heater ring 15 and terminating at the top surface of the heater ring below index table 22. Recess 33 and seating'guide 34 provide an air path up within the die so that air ejects a can from the seating die. It is understood that ejection is timed to occur when the detector head is clear of a particular seating die. This ejection occurs when the detector head has been moved up with the ram and the index table is moving to the next position, or may occur in an index position succeeding the detector station.

In order to return a depressed air valve control pin 35 to its normal upward position, heater ring 15 carries, at the inside surface thereof, stationary cam 162 having rise 163. This stationary cam is so disposed with relation to finger 156 as to return pin 35 to its top position after the valve has been actuated.

The detector station is disposed a number of index positions ahead of the crimping station. Following the crimping station in the direction of index table travel is a work discharge station. Thus referring to Figs. 1, 2 and 4, air valve 166 is carried by the machine, this air valve having its outlet connected to pipe'167. This pipe extends underneath the table bed up through the index table and heater ring just as in Fig. 6. Above the seating die at the discharge station, near the air valve, is the open end of U-shaped discharge pipe 169. Pipe 169 is large enough to accommodate the crirnped can and assembly and the air pressure from the valve is sufficient to blow a completed assembly and can out of the seating die into the discharge pipe to a suitable receptacle. Air valve 166 is actuated by cam 162 mounted on the valve body, this cam cooperating with cam roller 170 carried by a bracket on vertically movable ram 71.

It is understood that the air valves previously referred to have suitable connections for compressed air.

In order to prevent index table 22 from overrunning more than one index position at a time, detent 173 is provided, this detent being pressed by spring 174 against the teeth of the index table. -It is understood that spring 174 urges detent 173 strongly enough to prevent rotation of the table by momentum but will yield when the table is moved positively from one index position to the next index position.

The general operation of the machine will now be described. The machine normally is in theposition shown in Fig. 1 with the ram in its elevated position. Carn rollers 81 and are in the position shown with arms 83 and 79 of the bell cranks in their top positions. Rod 112 is elevated, sleeve 93 also being elevated with respect to die barrel 90. Guide block 103 is above and clear of any seating die so that the index table may move past the crimping station.

Upon the operation of the pedal at the bottom of the machine, as shown in Fig. 1, by an operator, the press will be permitted to go through one cycle as is usual with such machines. Cam disc 42 first operates the various cranks and levers to advance the index table through one index position. Also the ram starts to move down. Die block 103 telescopes the seating die immediately below it at the crimping station. The curling of the metal is accomplished as previously described. In the downward position of the ram, cam rollers 81 and 85 are allowed to move outwardly, sleeve 93 and rod 112 being free to assume the positions shown in Fig. 5. After the ram has begun to move upwardly, near the top of the stroke, cam rollers 81 and 85 are forced inwardly by cam surfaces 76 and 77. Thus while the ram and curling dies are being withdrawn upwardly from the seating die, sleeve 93 and rod 112 are moved downwardly with respect to the ram so as to maintain a stripping pressure against the pin and top of the assembly of the can. Thus, when the entire ram and die has cleared the seating die on the index table, the can and electrodes will have been stripped from the curling dies and other parts of the dies, and permitted to remain in the seating die.

At the detector station, the detecting and feeling action previously described will occur. Thus an empty can which may be present in a seatingdie will be detected and ejected from the seating die before reaching the crimping station.

The crimped can and electrode assembly will, of course, be blown out at the discharge position.

It will be understood that the various parts of the dies,

- a particularly the crimping die and stripper rods and pins,

1. In a machine for sealing metal cans having a base,

an index table carried by said base and rotatable around a vertical axis, means for advancing said index table by one index position at a time, seating dies carried by said index table, there being one such seating die for each index position, each seating die having a through channel vertically thereof and being adapted to receive a can and contents in said can, and crimping means for crimping the end of a can, the-improvement comprising means for detecting the presence of the contents in said can in advance of said crimping means, said detecting means including a detector head and feeler rod, means for moving the detector head and the feeler rod downwardly towards the index table when said table has reached an index position, said detector head being adapted to 'be stopped at its normal bottom position by the presence of the contents in a can disposed in said seating die with said feeler rod dropping to a corresponding predetermined normal bottom position, said detector head and said feeler rod moving below their respective normal bottom positions in the absence of the contents in said can, and means controlled by said feeler rod for discharging a can from its seating die before reaching the crimping means when the feeler rod is below its normal bottom position.

2. In a machine having a base, an index table mounted for rotation about a vertical axis, means for indexing said table, a crimping station including crimping means and a discharge station for said index table, said table having for each index position a seating die, said seating die being adapted to receive a can whose edge is to be crimped,

the improvement comprising detecting means movable vertically towards said index table and adapted to enter the end of a can supported on a seating die to detect the presence of a cover thereon which is to be sealed to the crimped edge of the associated can, a movable finger carried by said index table adjacent to each seating die and disposed in an opening in said index table, a pin carried by said detecting means for cooperation with the adjacent finger on said index table and adapted to move said-finger downwardly into said index table upon the presence of a can without a cover therefor, pneumatic means for discharging a piece of work from said seating die at said detecting station, means controlled by the vertical position of a finger for operating said pneumatic objecting means and means below said index table for restoring a finger which has been depressed-to an ejecting position back to a normal position.

3. In a machine of the character described having a movable index table carrying seating dies for receiving respective cans having covers which are to be sealed to the crimped edges of the associated can by means of a movable ram and associated crimping die, the improvement comprising means for detecting the absence of covers on said cans prior to the crimping operation and means for supporting said detecting means from said ram so that the two move together, a movable finger adjacent to each seating die and carried by said table, said detecting means having a range of travel which is normally limited by the cover on a can in a seating die but which range is increased upon the absence of a cover on a can, said detecting means including a feeler rod adapted to just touch said movable finger carried by the index table when saiddetecting means is in the limited down position, said feeler rod being adapted to move said movable finger downwardly when the detecting means travels the increased range, friction means for retaining said movable finger in any position to which said movable finger is moved, a valve-control finger in the path of a depressed movable finger, said valve-control finger being operated by a depressed movable finger when the index table is moving from the detecting means, a valve being thereby opened by said valve-control finger to discharge a blast of air through the bed into the seating die containing the defective can to discharge the same from its seating die and means supported from said bed and cooperating with a depressed movable finger for re turning the same to a normal raised position after said valve-control finger has been operated.

References Cited in the file of this patent UNITED STATES PATENTS 174,821 Johnson Mar. 14, 1876 941,085 Marthinson Nov. 23, 1909 983,001 Sharp Jan. 31, 1911 1,604,475 North Oct. 26, 1926 1,679,629 Rollman Aug. 7, 1928 1,763,458 Coyle June 10, 1930 1,846,319 Dister Feb. 23, 1932 1,929,339 Troyer Oct. 3, 1933 2,100,480 Hirshman Nov. 30, 1937 2,108,257 Earling Feb. 15, 1938 2,172,402 Nordquist Sept. 12, 1939 2,255,707 Kronquest Sept. 9, 1941 2,418,949 McNally Apr. 15, 1947 2,424,296 Zahodiakin July 22, 1947 2,467,930 Coyle Apr. 19, 1949 2,555,700 ONeil June 5, 1951 2,559,904 Swanson July 10, 1951

Images