US 3797228 A
Method and apparatus for making articles by passing stock material through heating, contour forming, and final shaping stations. Articles such as horseshoes are advantageously subjected to the combined steps of bending and nail hole punching at the final shaping station.
Description (OCR text may contain errors)
United States Patent [1 1 Kirkpatrick, deceased et a1.
ARTICLE MAKING MACHINE AND METHOD Alaska General Credit Corporation, Anchorage, Alaska Filed: Oct. 26, 1971 Appl. No.: 192,147
US. Cl. 59/37, 59/61 Int, .Cl B2lk 15/02 Field of Search 59/36, 37, 38, 40, 41,
References Cited UNITED STATES PATENTS 801.216 /1905 Chehet ..59/37 Mar. 19, 1974 330,670 11/1885 Bi11ing5 59/50 953,759 4/1910 Pedersen. 59/37 998,287 7/1911 Gandil 59/37 1,063,779 6/1913 Crone..... 59/50 1,586,540 6/1926 Tweedy 59/36 FOREIGN PATENTS OR APPLICATIONS 8,717 10/1897 Norway... 59/61 725,754 11/1930 France 83/171 Primary ExaminerCharles W. Lanham Assistant Examiner-Gene P. Crosby Attorney, Agent, or Firm-Strauch, Nolan, Neale, Nies & Kurz [5 7] ABSTRACT Method and apparatus for making articles by passing stock material through heating, contour forming, and final shaping stations. Articles such as horseshoes are advantageously subjected to the combined steps of bending and nail hole punching at the final shaping station.
22 Claims, 13 Drawing Figures o o o o o O 0 1s 68 o 216 154 138 37 249 I68 h o O o O o o o o o 9e 2e |44 7s 72 24/ I4 74 22 67 1 ARTICLE MAKING MACHINE AND METHOD BACKGROUND AND SUMMARY OF THE INVENTION This invention relates to methods and apparatus for the efficient, accurate formation of metal articles of desired shape, and is particularly directed to methods and apparatus for automatically hot-forming lengths of metal stock into a series of articles of special shape.
In its preferred embodiment, the invention will be described as a method and apparatus for making horseshoes from metal stock of predetermined cross section introduced in sequence through heating, contour forming, and bending and punching stations. It will be understood however, as'the claims will indicate by their scope, that the invention includes applicability to the formation of other articles.
Apparatus and methods for forming horseshoes from bar stock have been proposed as disclosed in US. Letters Pat. No. l,463,0l2 wherein a length of bar stock is heated and sheared into suitable blanks that are bent and shaped in automatic sequence. The present invention represents an improvement over earlier apparatus and methods, particularly in the forming sequences.
In the invention, heated blanks are punched from the heated leading end of bar stock of predetermined cross section in a contour die, and then the blanks are automatically fed to a further station where they are bent and also may be subjected further to shaping or forming, and this is a major object of this invention. Where the articles are horseshoes, the further shaping or forming may include punching of the nail holes into the blank after bending.
For many aspects of the invention, particularly where the stock is steel or aluminum, the leading end of the stock may be locally electrically resistance heated to about the length of the desired blank and this is a further object of the invention.
The invention particularly embodies as its major object the methods and apparatus for control of the article forming sequence, both as to subcombinations thereof and as to the overall combination of all controls that combine to effect speedy accurate production of articles of desired shape from long bar stock.
Other objects and advantages will become apparent from reading the following detailed description of a preferred embodiment of the invention wherein reference is made to the accompanying drawings in which like numerals indicate like elements.
BRIEF DESCRIPTION OF DRAWINGS FIG. 1 is a front elevation view diagrammatically illustrating the method stations and apparatus according to a preferred embodiment in the invention;
FIG. 2 is a diagrammatic, enlarged front elevation view showing the heating station of FIG. 1;
FIG. 3 is a side elevation taken generally along line 3-3 of FIG. 2 and showing the bar stock clamp and heating electrode structure;
FIG. 4 is a diagrammatic enlarged front elevation of the upper and lower die assemblies located at the blank contour forming and cutting station of FIG. 1;
FIG. 5 is a fragmentary view of the upper contour die assembly taken generally along line 5-5 of FIG. 4;
FIG. 6 is a fragmentary view of the lower contour die assembly taken generally along line 6-6 of FIG. 4;
FIG. 7 is a fragmentary enlarged front elevation view of the bending and punching apparatus located at the final shaping station of FIG. 1; 1
FIG. 8 is a fragmentary right side elevation view of the bending and punching apparatus shown in FIG. 7;
FIG. 9 is a fragmentary plan view of the die assemblies of the bending and punching apparatus taken generally along line 9-9 of FIG. 8, and schematically illustrating the successive positions of the blank during the bending operation;
FIG. 10 is a fragmentary plan view of the control rod and switch arrangement for the bending and punching apparatus as taken generally along line 10-10 of the FIG. 8;
FIG. 11 is a fragmentary left side view taken along line 11-11 of FIG. 10;
FIG. 12 is a bottom plan view taken generally along line 12-12 of FIG. 8 and illustrating the bottom dieforming surface of the upper die assembly of the bending and punching apparatus; and
FIG. 13 is an electrical schematic diagram of the control circuitry operated by the control rod arrangement of FIGS. 10 and 11, for automatically controlling operation of the bending and punching apparatus.
DETAILED DESCRIPTION OF THE INVENTION Referring to FIG. 1, a summary operation of the method and apparatus of the invention will first be described. A metal bar stock 20 of predetermined cross section is fed either manually or automatically into heating station 22 wherein the leading end of the bar stock is resistance heated to about 2,000F. The leading end is then passed to the contour and cutting station 24 where it is punched and cut off to provide a horseshoe blank 26 of desired shape and contour. The hot blank 26-is then delivered to a final shaping station 28 at which it is bent into a desired shape, e.g., a horseshoe, and then punched to provide nail holes in the horseshoes, with the finished shoe then being ejected from the shaping station 28. The entire bending and punching operation is automatically controlled to provide quick, accurate, and efficient final shaping of successive hot blanks into horseshoes.
With reference now to FIGS. 1-3, the bar stock 20 of preformed cross section (see FIG. 3) may be provided in 20 foot bar lengths or may be rolled in a continuous bar form on a reel, in which case the bar stock will be passed between straightening dies or rolls before being fed to the heating station 22. In either situation,
the bar stock is pushed longitudinally into heating station 22 until its leading end rests between the spaced clamp assemblies 30 and 32, both of. which are of identical construction. Each clamp assembly includes a stationary lower bar support or holder 34 having an upper support strip 36 on which the bar rests, and an upper pivoted L-shaped clamp arm 38 pivotally connected by pin 40 between a pair of vertical side plates 42 and 44 which are fixed to the sides of holder 34. Each arm 38 is pivotally connected at 48 to the forward end of a rod 50 of a suitable pneumatic diaphragm actuator 52 which is fixed to the upper plates 42 and 44. Normally, actuator 52 will retain arm 38 in a raised position to enable the leading end of bar 20 to be pushed into place on holders 34.
As shown best in FIG. 3, the clamping surface 46 of arm 38 is cylindrical and conforms generally with a portion of the upper surface of bar 20. Similarily, the support surface of strip 36 conforms generally to the rear and bottom surfaces of bar 20. Consequently, the bar is securely clamped in place during the heating operation.
The lower clamp holders 34 form the electrodes in a resistance heating circuit which heats the leading end of the bar clamped between assemblies 30 and 32. Holders 34 are connected via electrical cables 54 and 56 to the secondary of transformer 58. Power to the primary side of the transformer is controlled as follows. When the leading end of bar is in place on support strips 36 of holders 34, the operator will push a start or heat button (not shown) to deliver pressurized air to pneumatic actuators 52 and thereby pivot arms 38 into the clamping position of FIG. 3 on the bar. When the bar is clamped, the pressure buildup in the pneumatic supply to actuators 52 is sensed by a pressure switch 60 which closes to energize a solenoid valve 62 and close switch 64, thereby, providing current to the primary of transformer 58 from a high voltage source. As a result, current is supplied to holders-electrodes 34 and the leading end of bar 20, clamped between the holders, is resistance heated for a predetermined period of time sufficient to heat the leading end to a temperature of about 2,000F. The heating time period is controlled by a time switch 66 which is opened to cut off the heat and deactivate actuators 52 to release the clamps. During the heating cycle, the holders-electrodes 34 are preferably water cooled by a water supply system including flexible conduit 67 (FIG. 1).
Following the heating cycle, the bar is indexed longitudinally a sufficient distance to bring the heated end between the upper and lower die assemblies 68 and 70, respectively, of the punch press or contour forming and cutting machine located at station 24. As shown in FIGS. 1 and 4-6, the lower stationary female die assembly 70 includes lower die shoe 72 which is fixed on the horizontal table or base 74 of the cutting machine, spaced side support plates 76 fixed on shoe 72, and a lower die block 78 mounted and guided in plates 76 and formed by left and right die insert sections 80 and 82, respectively, which together define a lower female die opening 84 corresponding to the shape and length of the blank which is to be cut from the hot leading end of bar 20. The insert sections 80 and 82 have their inner surfaces 86 and 88 spaced from each other so that the center portion of the blank produced by the cutting operation will correspond to the original cross sectional configuration of the bar stock as shown in FIG. 3. Right insert section 82 is retained in place by an end support block 90 and a plurality of removable spacer blocks 92. By removing or inserting one or more of spacer blocks 92 and shifting insert section 82 laterally, the effective length of die opening 84 may be increased, thereby permitting the length of the blank which is cut to be varied, depending upon the size of the horseshoe desired. A plurality of set screws 93 retain section 82 in a set position.
Shoe 72 has an elongated slot 94 through which the punched blank drops onto a longitudinal feed channel 96 which extends from underneath slot 94 to the final shaping station 28. Also, a pair of stripper guide bars 98 are mounted along the front and rear of the top surface of support plate 76 for a purpose described herein after.
The upper male punch die assembly 68 includes an upper die shoe 100 fixed to the vertically reciprocable ram 101 operated by crankshaft 102 of the punch press, and left and right die sections 104 and 106. Left die section 104 includes a punch support guide 108 fixed to shoe 100 and mounting a punch die insert 110 formed with a male die face 112. Right die section 106 includes front and rear support guides 114 and 116 fixed to shoe 100 and slidably mounted a punch support 117 that receives a punch die insert 118 which has a male die face 120. Die faces 112 and 120 are mirror images of each other to provide a symmetrical blank 26.(FIG. 9) The inner surfaces 122 and 124 of die faces 1 l2 and 120 are spaced from each other a distance corresponding to the spacing between the lower die faces 86 and 88. Also, a plurality of removable spacer blocks 126 are positioned between an end support block 128 fixed to shoe 100 and the outer end of die section 106, so that the lateral positions of die section 106 may be adjusted in correspondence with the lateral position of lower die section 86 to vary the length of the blank 26 punched from the hot leading end of the bar. A plurality of set screws 130 retain support 117 in a set position. For purposes of stabilization, a center support block 132 is positioned between the inner surfaces of left support guide 108 and right guide sections 114 and l 16.
As shown in FIG. 1, and schematically in FIGS. 4 and 5 upper die assembly 68 also includes a pair of stripper plates 134 and 135 which are resiliently supported from die shoe 100 by a plurality of spring assemblies 136 in a position normally below the cutting faces of dies 112 and 120. The stripper plates surround the end of the male die assembly, as shown schematically in broken line in FIG. 5. During the cutting and coutour forming of the blank, plates 134 and 135 engage and hold the portions of the hot leading end of the bar outside the ends of die opening 84 against the outer edge of left lower die section 80 and against the outer edge of right die section 82 or spacer blocks 92, depending upon the setting of the dies.
Also during operation, support plate 76 of the lower die assembly and the punch support guides 108 and 117 are water cooled by conduits 137 to protect the dies and the holding structure of the die assemblies.
Operation at the contour cutting station 24 is as follows. The hot leading end section of bar 20 is moved from heating station 22 onto the lower die assembly 70 so that a central portion of the hot bar section overlies the female die opening 84 and the end portions of the hot bar section extend beyond the ends of opening 84 in resting engagement on the outer edge portion of die section 80 and on spacer blocks 92. When the bar is so positioned, a switch (not shown) is operated to rotate crankshaft 102 and move ram 101 and attached upper die assembly 68 downwardly. Stripper plates 134 and 135, guided within stripper guides 98 of lower die assembly 70, first engage and clamp the end portions of the hot bar section in place, then the cutting punching die faces 112 and 120 and cooperating female die opening 84 shear the blank 26 from the hot bar section, and the blank, corresponding to shape of the die opening 84, drops through slot 94 onto feed channel 96. Immediately following the cutting operation, an air blast is provided from nozzle 138 mounted on stripper plate 134 (FIG. 1) to remove the waste terminal cut-off end of bar stock material from the punch machine.
It should be noted that during the contour cutting operation only the ends'of the shoe blank 26 are cut and formed, and because of the center spacing between lower die surfaces 86, 88 and upper die surfaces 122, 124, the central portion of the blank will correspond to the cross section of the original bar stock 20. It should also be noted that the blank is simultaneously cut from bar stock' 20 and formed to its desired contour in a single punch operation, and this is an important advantage of the invention.
After hot blank 26 falls onto feed channel 96, the rod of an air cylinder 140 (FIG. 1) which is automatically operated in timed sequence with ram 101 of the punch press, then pushes the blank along channel 96 into the final shaping station 28 at which the hot shoe blank is bent into the desired horseshoe shape and nail holes are punched in the shoe.
Referring to FIGS. 7-12, the bending and nail hole punching machine at station 28 includes a frame 142 which has a horizontal table section 144 on which a lower die mounting plate 146 is fixed. At its upper end, frame 142 mounts a vertically reciprocable punch ram 148 which is driven by a crankshaft 150. The crankshaft is driven through a normally disengaged clutch unit 151 from wheel 152 and motor 153. Clutch unit 151 is engaged upon movement of vertical actuating lever 154 which is guided by a bolt 154a whose end slidingly ab'utsagainst frame 142. An arm l54b is connected to the lower end of lever 154, and the rear end of arm 154b is connected to the plunger of the punch solenoid PS fixed to frame 142. Clutch unit 151 is of a type which engages or trips only one time upon energization of solenoid PS so that crank shaft 150 rotates only one time each time solenoid PS is energized. Following rotation of crank shaft 150 through one revolution, clutch 151 disengages and will not reengage until solenoid PS is first deenergized and then again reenergized. As will become apparent, an upper bending and punch die assembly 155 is mounted for in and out (rearward and forward) reciprocation on plate 146 into operative association with ram 148.
As best shown in FIGS. 7 and 9, a removable lower die plate 156 is fastened on mounting plate 146 by a plurality of flat head screws 158, with die plate 156 being provided with a plurality of apertured, punch receiving inserts 160 and an opening 162 underlying each of the inserts. As an alternative to the inserts, plate 156 may be formed as an integral hardened die plate. Die plate 156 also has a locating and centering opening 164. The portion of table section 144 underlying the die plate 156 is hollow or open to permit the punched stock material falling through openings 162 to fall free of the machine and the mounting plate.
A pair of formingroller assemblies 166 and 168 are mounted on mounting plate 146, and each assembly includes a stationary horizontal bracket 170 fixed to plate 146 and having a vertical end flange 172, an intermediate guide flange 174, and an inner hold down guide flange 176 fixed thereto. A roller support arm 178 is slidably mounted on bracket 170 by flanges 174 and 176 and has a forming roller 180 rotatably mounted on its inner end about a vertical axis for rotation on the horizontal plates 146 and 156. Roller 180 has an upper enlarged annular rim 181 which engages the top surface of the blank as it is bent into shape. The outer vertical flange 182 of arm 178 is engaged by one end of coil spring 184, the other end of which abuts 194 provided with a pair of side channel members 196 at its upper end, with a guide roller 198 rotatably connected to each channel member 196. The rear end of block 194 is bolt connected to the piston rod 200 of hydraulic cylinder 202 which is mounted on an integral rearward extending bar portion 204 of mounting plate 146. To move rod 200 in or out, cylinder 202 is operated through solenoid operated, directional control valve 255 by fluid from a pump 203 which is driven by motor 153. Acontrol rod 206 (FIGS. 10 and 11) is secured by bracket 207 to the rear end of piston rod 200 for reciprocating movement therewith, with rod 206 being guided by a bracket 208 which is fixed to bar 204. As described hereinafter control rod 206 operates a number of switches in the control circuit for the bending and punching cycle.
In its normal inoperative position, block 194 will be positioned as shown in FIGS. 8 and 9 at the front edge of plate 146 in spaced relation from forming rollers 180 so that the hot blank 26 fed to the shaping machine will be positioned between the bottom shaping die face 210 v of block 194 and the forming rollers 180. As block 194 is moved rearwardly by activation of cylinder 202, hot blank 26 is bent into horseshoe shape as rollers 180 force the blank to conform to the shape of die face 210. Rearward or in movement of block 194 is guided by engagement of guide rollers 198 with guide strips 212, each of which is secured at its inner end 214 to frame 142 and its outer end 215 to the outer end of a turnbuckle coupling 216, the inner end of which is secured to frame 142. A transverse stabilizing bar 218 (FIG. 7) extends between the front outer ends of strips 212.
As shown best in FIGS. 7 and 12, die block 194 includes the bottom die shaping surface 210 corresponding to the shape of a horseshoe, with the shaping surface 210 extending upwardly in contour fashion from a bottom flat surface 220 which slides across die plate 156 to a shoulder 222 of an enlarged section 224. A plurality of nail hole punch receiving holes 226 are provided along each side of shaping surface 210, and a punch centering hole 228 is provided to align with centering opening 164 of die plate 156 during the nail hole punching operation after the blank is bent intohorseshoe shape.
A nail hole punch unit 230 forms part of the upper die assembly and includes a plate 232 and a plurality of downwardly extending punches 234 fixed to plate 232. A plurality of springs 236 surrounds all or at least some of the punches 234, and the springs 236 normally resiliently retain plate 232 in a raised position above block 194, with the lower ends of punches 234 received in the upper ends of holes 226 of block 194. A centering pin 238 is also fixed to plate 232 and extends into opening 228 of block 194. Pin 238 has a-tapered lower end 240 which enters hole 164 in die plate 156 to properly center upper die assembly 155 with die plate 156 before punches 234 punch the nail holes in the bent shoe. Pin 238 also includes an intermediate, reduced cross sectional area 242 which receives a collar 244 that is fixed to block 194, with area 242 and collar 244 cooperating to retain plate 232 and punches 234 in connection with block 194 as shown in FIG. 7.
As die assembly 155 is moved in by rod 200 of cylinder 202, punch plate 232 is moved into proper operative relationship with ram 148 of the punch press and a pair of stripper channels 246 and 248, which are fixed to the bottom end of the ram.
Mounting plate 146 is preferably water cooled during operation via conduit 249 (FIG. 1). Similarly die block 194 is water cooled by suitable conduits (FIG. 1).
The entire horseshoe bending and nail hole punching operation is automatic and will now be described with general reference to FIGS. 7-13. Assume that main switch S1 and punch switch P1 in FIG. 13 are closed. Motor 153 will be rotating, but crankshaft 150 will be at rest becauseclutch unit 151 is disengaged. The hot blank 26 from cutting station 24 is pushed along feed channel 96 by air cylinder 140 onto the front edge of mounting plate 146 into position between die block 194 and forming rollers 180 as shown best in FIGS. 8 and 9. When the leading end of blank 26 engages and closes switch S2 located at the far end of mounting plate 146 (left end as viewed in FIG. 7 and top as viewed in FIG. 9) air cylinder 140 will be deactivated by circuitry (not shown) to return the cylinder back to its start position in readiness for the next blank cut at the station 24. In FIG. 13, closure of switch S2 will cause current to flow from supply line 250, through crank operated switch S5 which will be positioned as shown because crankshaft 150 is at rest, line 252, a die in" solenoid 254 of directional control valve 255 in the fluid circuit (not shown) to cylinder 202, line 256, closed switch S2, line 258, closed contact S7-1 of a double pole, double throw toggle switch S7, line 260, switch S4, lines 262 and 264 to supply line 266. Consequently, in" solenoid 254 will be energized to operate cylinder 202 and pull rod 200 in (to the rear) thereby displacing die block 194 inwardly over lower die plate 156. As control rod 206 moves in with rod 200, follower arm 270 of switch S3 will ride out of detent 272 of rod 206 and will close switch S3 to bypass switch S2 which eventually opens as blank 26 is bent.
As shown schematically in FIG. 9, as block 194 moves inwardly, the rear portion of shaping surface 210 moves hot blank 26 rearwardly a short distance until the blank engages forming rollers 180. This position is shown at A in FIG. 9. Continued in movement of block 194 and the transverse bending forces produced by rollers 180 and their spring supports cause blank 26 to be bent into horseshoe shape around shaping surface 210. The blank will attain its final houseshoe shape at the punch position B of FIG. 9 wherein block 194 will overlie die plate 156 in such a way that opening 228 will align with opening 164 and openings 226 will align with the apertured inserts 160. Rollers 180 will be positioned in their fragmentary bro ken line position.
When blank 26 is finally shaped to its horseshoe configuration (the punch position B of FIG. 9), control rod 206 will have moved in a sufficient distance to enable follower arm 274 of switch S4 to ride in recess 276 of rod 206, thereby moving switch S4 from its upper contact position to its lower contact position. At this point, trip pin 282 will still be positioned in front of or outwardly from arm 284 of switch S7. As switch S4 drops to its lower contact position, end solenoid 254 will be deenergized to deactivate cylinder 202 and stop movement of rod 200 to position block 194 in the punch position B of FIG. 9. Punch plate 72 will then be located with strippers 246, 248 underneath ram 148. Movement of the switch S4 to its lower contact position also energizes punch solenoid PS through supply line 250, closed switch P1, solenoid PS, switch S4, and lines 262, 264, and 266. Energization of solenoid PS actuates arm 154b and lever 154 (FIGS. 7 and 8) to engage clutch 151 and thereby drive crankshaft from the rotating wheel 152. As crankshaft 150 is rotated, punch ram 148 is rapidly moved downwardly to strike plate 232 which initially causes the centering pin 238 to enter opening 164 of lower die plate 156 and ensure that openings 226 of block 194 are properly aligned with the apertured inserts 160 and openings 162 of plate 156. Subsequently, the lower ends of punches 234 pierce through the horseshoe blank to form the nail holes in the shoe. It is understood, of course, that the centering and punching steps occur in very rapid sequence and are almost simultaneous.
Crankshaft 150 is formed at its outer end with a cam detent 151a which engages follower arm 278 to retain switch S5 in the upper contact position when clutch 151 is not engaged and crank-shaft 150 is at rest. Upon engagement of clutch 151 and initial rotation of the crankshaft, follower arm 278 is released and switch S5 drops to its lower contact position to energize the relay coil 280 of a time relay TR which closes switch S6 and holds it closed for a short time, for example, one second. As described previously, because of the construction of clutch 151, crankshaft 150 rotates only through one complete revolution to raise plate 232 and punches 234, and cause the switch S5 to return to its upper contact position which again energizes in solenoid 254 by way of contact S7-1, which is still closed, and closed switch S6. Energization of in solenoid 254 causes rod 200 to move in a short distance until trip pin 282 on control rod 206 shifts actuator arm 284 of switch S7 in or to the rear to open contact 87-1 and close contact S7-2. Switch S6 will also be opened by the time relay TR. Consequently, in solenoid 254 is deenergized to stop inward movement of rod 200, and out solenoid 286 is energized by current flow from line 252 through solenoid 286, line 288, closed contact 57-2, and lines 290, 262, and 264. Cylinder 202 will then be actuated in the reverse or out direction to move rods 200 and 206 out. As rod 206 moves out, follower 274 rides out of recess 276 to shift switch S4 back to its upper contact position, thereby deenergizing punch solenoid PS. Crankshaft 150 will be at its rest position shown schematically in FIG. 13. Outward movement of rods 200 and 206 trips arm 284 outwardly to close switch 87-1 and open switch S7-2. Out solenoid 286 is deenergized to stop outward movement of rod 200 and die assembly 155, thelatter of which will be located outwardly beyond the edge of plate 146 a distance sufficient to permit the finished horseshoe to be released from block 194 and ejected from the bending and punching machine.
The closing of switch S7-l causes in" solenoid 254 to be energized again via switches S3 and S4 which are also closed. As a result, rods 200 and 206 and die assembly will again be moved in until follower 270 again rides into detent 272 to open switch S3 at which time in solenoid 254 is deenergized. Rod 200 and die assembly 155 are then ready for the next bending and punching cycle.
The described bending and nail hole punching operation at station 28 proceeds very rapidly and requires only about 2 seconds per shoe. Therefore, it is apparent that the method and apparatus of the invention are readily adaptable to high production schedules.
The described method and apparatus is particularly adapted for production of the horseshoe described and claimed in US. Pat. No. 3,578,087. The cross section of the preformed bar stock 20, the shape and configuration of the contour forming and cutting die assemblies 68 and 70 at station 24, and the configuration of the bending and nail hole punching assemblies 155 and 156 at station 28 are especially designed to produce that shoe.
As pointed out in the objects set forth hereinabove, the method and apparatus of the invention are not limited to the production of horseshoes, but may be used for producing articles of various shapes and sizes merely by changing the die assemblies as necessary. For example, if an article being produced merely requires the final bending step at station 28, but not the nail hole punching step, the switch P1, in FIG. 13 may be opened to prevent energization of the punch solenoid PS and thereby eliminate the punching step from the overall operation at station 28.
The invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. The present embodiment is therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.
What is claimed and desired to be secured by Letters Patent is:
1. A method of forming a series of identical shaped articles in succession from an elongated length of metal stock that has a predetermined cross section comprising the steps of heating the leading end of said stock to forming temperature for a distance at least equal to the length of a desired article blank, feeding the heated leading end of the stock a predetermined distance into a contour die station wherein a heated blank is severed from the stock while the blank is being subjected to a first shaping operation, and then automatically feeding the heated partially formed blank into a bending station wherein said blank is bent about an intermediate portion thereof and formed to final shape, and repeating the foregoing cycle of steps. 1
2. The method defined in claim 1, wherein eachsaid heated blank is bent to form a horseshoe at said bending station, and further comprising the step of punching nail holes into each bent heated horseshoe blank at said bending station to substantially complete the horseshoe.
3. Apparatus for forming a series of identical shaped articles in succession from an elongated length of metal stock that has a predetermined cross section comprising means for heating the leading end of said stock to forming temperature for a distance at least equal to the length of a desired article blank, means adjacent said heating means providing a contour die station for receiving the heated leading end of said stock and containing means whereby a heated blank is severed from the stock while the blank is being subjected to a first shaping operation, means at said contour die station for longitudinally indexing said stock therein for severing and shaping, and means for automatically feeding the heated partially formed blank into a bending station containing means whereby said blank is bent about an intermediate portion thereof and formed to final shape.
4. The apparatus defined in claim 3, wherein said blank is bent to form a horseshoe at said bending station and means is provided at said bending station for automatically forming nail holes in the bent horseshoe.
5. The apparatus defined in claim 3, wherein said heating means is an electrical resistance heating assembly having electrode means for clamping the leading end of said stock.
6. Apparatus for forming shaped metal articles comprising a contour die unit, means for introducing the heated end of a length of metal stock into said contour die unit wherein a blank of predetermined length is severed and at the same time shaped to a predetermined contour, means for moving said severed hot blank into a bending station, and means at said bending station for relatively moving said blank and a bending die element to form said hot blank to the shape of the desired article, and means for automatically ejecting the article from said bending station.
7. Apparatus as defined in claim 6, comprising punch means at said bending station for punching predetermined formations into the bent hot blank to substantially complete the shaping of said article at said bending station.
8. Apparatus for forming shaped metal articles comprising a contour die unit, means for introducing the heated end of a length of metal stock of preformed shape into said contour die unit wherein a blank of predetermined length and contour is severed, said contour die unit being so constructed so as to contour and cut only the end portions of said blank, with the center portion of said blank conforming substantially to the preformed shape of said metal stock, means for moving said severed hot blank into a bending station, and means at said bending station for relatively moving said blank and a bending die element to form said hot blank to the shape of the desired article, and means for ejecting the article from said bending station.
9. Apparatus as defined in claim 8, wherein said contour die unit is adjustable so that the length of the blank severed may be varied as desired.
10. Apparatus for forming shaped metal articles comprising a contour die unit, means for introducing the heated end of a length of metal stock into said contour die unit wherein a blank of predetermined length and contour is severed, said contour die unit being adjustable so that the length of the blank severed may be varied as desired, means for moving said severed hot blank intoa bending station, and means at said bending station for relativelymoving said blank and a bending die element to form said hot blank to the shape of the desired article, and means for ejecting the article from said bending station.
Ill. Apparatus as defined in claim 10, comprising punch means at said bending station for punching predetermined formations into the bent hot blank to substantially complete the shapingof said article at said bending station.
12. Apparatus for making horseshoes or the like comprising means for clamping the leading end portion of a length of preformed metal stock, means for heating the clamped end portion of the stock, a contour die unit into which said heated end portion is introduced and which is operable to sever a blank of predetermined length and lateral contour therefrom, means defining a bending station, a horseshoe defining die element at said bending station, and means at said bending station for bending said blank around said horseshoe defining die element.
13. Apparatus as defined in claim 12, said clamping means comprising a pair of clamp assemblies which grip spaced portions along said leading end portion of said metal stock, said heating means comprising an electrical resistance heating circuit in which the electrodes are formed by at least part of the spaced clamp assemblies, whereby said leading end portion of said metal stock is electrically resistance heated.
14. Apparatus as defined in claim 13, comprising pressure responsive means for opening and closing said clamp assemblies, and control means comprising means responsive to energization of said electrical heating circuit for actuating said pressure responsive means to tightly clamp said metal stock, switch means activated when said metal stock has been clamped to energize said electrical heating circuit to heat the leading end portion of said metal stock gripped between said clamp assemblies, and time responsive switch means for deenergizing said heating circuit and deactuating said pressure responsive means to release the heated leading end portion of said metal stock from said clamp assemblies.
15. Apparatus as defined in claim 12, wherein said contour die unit is so constructed so as to contour and cut only the end portions of the said blank, with the center portion of said blank conforming to the shape of the preformed metal stock.
16. Apparatus as defined in claim 15, wherein said contour die unit is adjustable so that the length of the blank severed may be varied as desired.
17. Apparatus as defined in claim 12, wherein said contour die unit is adjustable so that the length of the blank severed may be varied as desired.
18. Apparatus as defined in claim 12, comprising punch means at said bending station for punching nail holes into the bent hot blank to substantially complete the shaping of the horseshoes at said bending station.
19. Apparatus for shaping a metal blank into a horseshoe or the like, contour die means for receiving and longitudinally indexing the leading end of a length of metal stock and containing means for shaping the blank to desired contour while severing it from said stock, means for feeding the severed blank into a bending station comprising a support, a pair of forming means mounted on said support, a horseshoe shaped die unit, actuating means connected to said die unit for moving said die unit across said support between said forming means to bend said blank into a horseshoe shape, and
punch means for punching nail holes in the bent blank to substantially complete the shaping of the horseshoe.
20. Apparatus for shaping a metal blank into a horseshoe or the like comprising a support, a pair of forming means mounted on said support, a horseshoe shaped die unit, actuating means connected to said die unit for moving said die unit across said support between said fonning means to bend said blank into a horseshoe shape, punch means for punching nail holes in the bent blank to substantially complete the shaping of the horseshoe, electrical control means for automatically controlling the bending and punching of said blank comprising first switch means responsive to the arrival of a blank on said support in a position between said die unit and said forming means to activate said actuator means and thereby move said die unit in one direction between said forming means to bend said blank, second switch means operable when said blank has been bent to deactivate said actuator means and actuate said punch means, and third switch means operable after the nail holes have been punched to activate said actuator means and move said die unit in a reverse direction to a position at which the shaped horseshoe is ejected from said support. I v
21. Apparatus for shaping a metal blank into a horseshoe or the like comprising a support, a pair of forming means mounted on said support, a horseshoe shaped die unit, actuating means connected to said die unit for moving said die unit across said support between said forming means to bend said blank into a horseshoe shape, punch means for punching nail holes in the bent blank to substantially complete the shaping of the horseshoe, a lower die plate mounted on said support and having a plurality of punch receiving openings therein, said die unit comprising a die block having a shaping surface against which the blank is bent and a plurality of punch receiving openings, said punch means comprising a reciprocable ram mounted above said support and a punch assembly resiliently mounted on said block, and said punch assembly including a punch plate and a plurality of nail hole punches fixed to said plate in alignment with the punch receiving openings in said die block,'whereby when said blank has been bent and is located on said support in its punch position, said punch plate being operatively aligned with said ram and said punch receiving openings in said die block being aligned with the punch receiving openings in said die plate so that the nail holes may be punched through the bent blank.
22. Apparatus as defined in claim 21, said punch assembly comprising a centering pin, each of said die block and said lower die plate having a centering opening, whereby during the punch operation said centering pin enters the centering openings before said punches engage said blank to ensure proper alignment of said die block and said blank with said lower die plate.