US2629503A - Box unstacker - Google Patents

Description

Feb. 24, 1953 A. A. NEJA 2,629,503

BOX UNSTACKER Filed Dec. 6, 1948 7 Sheets-Sheet l INVENTOR.

\ AMBROSE A NEJA WNW 47 TOEA/EY '7 Sheets-Sheet 2 A. A. NEJA BOX UNSTACKER Filed Dec. 6, 1948 Feb.

on w 3 I NVEN TOR.

AMBROSE A. NEJA ATI'OAA/ey Feb. 24, 1953 A. A. NEJA 2,629,503

BOX UNSTACKER Filed Dec. 6, 1948 7 Sheets-Sheet 5 INVENTOR.

AMBROSE A. NEJA BY ATTORNEY Feb. 24, 1953 A. A. NEJA 2,629,503

I B'OX UNSTACKER Filed Dec. 6, 1948 7 Sheets-Sheet 4 A BROSE A. NEJA as k- BY M ATTORNEY Feb. 24, 1953 A. A. NEJA ,5

BOX UNSTACKER IIIIIIII'IEI a4 INVENTO. YA'MBROSE A. NEJA Patented Feb. 24, 1953 UNITED STATES PATENT OFFICE BOX UN STACKER Ambrose A. Neja, Anaheim, Calif.

Application December 6, 1948, Serial No. 63,717

14 Claims. 1

This invention relates to a box unstacking apparatus.

The general object of the invention is to provide a novel apparatus which will operate to remove boxes from a stack and place the removed boxes upon a conveyor.

A further object of th invention is to provide a box unstacker includin novel means for removing the lower boxes of a stack one by one.

Another object of the invention is to provide a box unstacking apparatus including novel holding means which serve to engage and support certain boxes of a stack while other boxes of a stack are being removed from the stack.

A. further object of the invention is to provide a box unstacking apparatus including novel pivoted holding means in the form of arms which are mounted to move towards and from boxes in a stack to engage and hold certain boxes in the stack.

Another object of the invention is to provide a box stacking apparatus including novel lowerator means for lowering lower boxes of a stack while the upper boxes of the stack are held in stacked condition.

A further object of the invention is to provide a novel lowerator for a box stacking apparatus including novel means for engaging and lowering the lower boxes of a stack.

A further object of the invention is to provide a box stacking apparatus including novel holdin means and lowerator means by means of which a stack of boxes may be held and the lower boxes may be removed from the stack.

A further object of the invention is to provide a novel means for operating a box unstacking apparatus.

Another object of the invention is to provide a box handling mechanism including novel means for aligning the boxes.

Other objects and advantages of the invention will be apparent from the following description taken in connection with the accompanying drawings, wherein:

Fig. 1 is a top plan view of the unstacker in a position to receive a stack of boxes.

Fig. 2 is a side elevational view with the stacker in the same position as shown in Fig. 1.

Fig. 3 is a front view of the unstacker.

Fig. 4 is a fragmentary sectional view taken as indicated by line 44 of Fig. 1, with the unstacker in the same position as in Fig. 1.

Fig. 5 is a fragmentary sectional view taken as indicated by line 5-5 of Fig. 4.

Fig. 6 is a view similar to Fig. 5, with parts in different positions and showing the lowerato ready to receive a stack of boxes.

- Fig. 7 is a view similar to Fig. 5, with the lowerator in its uppermost position.

Fig. 8 is a view similar to Fig. 5, with the lowerator in position to place an unstacked box on the outgoing conveyor.

Fig. 9 is a fragmentary view taken as indicated byline 9-9 of Fig. 4.

Fig. 10 is a schematic diagram showing the construction and operation of the chain raising and lowering clutch mechanism and safety features associated therewith.

Fig. 11 is a fragmentary sectional view taken substantially as indicated by line i ll l of Fig. 4.

Fig. 12 is a schematic wiring diagram of the unstacking apparatus.

Fig. 13 is a fragmentary sectional view taken on line l3-|3 of Fig. 9, and

Fig. 14 is a fragmentary enlarged side elevation showing the pivot rod and associated parts.

Referring to the drawings by reference characters, I have shown my invention as embodied in a box unstacking apparatus which is indicated generally at H]. As shown the apparatus ncludes a frame ll, feed chains l2, elevating chains I3, a lowerator apparatus M, a lowerator driving mechanism [5, a holding mechanism I6 for holding a stack of boxes, controlling means I! for controlling the holding mechanism I6, and delivery chains I8. The boxes shown at B consist of ends B bottoms B a pair of side boards B and top cleats B The frame I l comprises a pair of longitudinal, parallel floor support angles 20 and 2|, adapted to be fastened to a floor 22, which has a well 22' therein.

Forward vertical support angles 23 and 24 and longer rear vertical support angles 25 and 2G serve to support most of the unstacking apparatus. Supports 23 and 25, 24 and 26 are connected at their tops by angles 21 and 28 and at their bases by angles 29 and 30 and are fixed as at 3i to the floor support angles 20 and 2|.

The bases of the forward supports 23 and 24 are further secured in spaced relation by angles 32 and 33, and the rear supports 25 and 26 are secured by an angle 34. Support members 35 and 36 serve to brace the center of the apparatus and an angle 37 braces the upper portion of the rear supports 25 and 26. Th angles which compose the frame may be secured to one another as by welding. The entire vertical portion of the frame is disposed at a slight angle to the Vertical as shown in Fig. 4 for a purpose to be later described.

At the outer forward ends of the floor members 23 and 2I I arrange a cross member 40 supported from the floor members 29 and 2I by angles II and 42. The cross member 49 acts as a forward support for longitudinal bearing supports 43 and 44 (Fig. 3), which make a slight jog downward as at 44' (Fig. 4) and continue rearwardly to the rear end of the well 22' in which the unstacker is placed. The rearward end of the supports 43 and 44 is-supported by the angle 34.

The incoming chains I2 consist of a pair of chains 45 and 48 which may extend out in channels 41 in the floor 22 for any desired distance from th unstacker and serve to deliver stacks of boxes to the machine. The inner ends of the chains 45 and 45 terminate at sprockets 48 and 49, mounted on a shaft 50 which is journaled in bearing blocks 5| and 52 fixed to the bearing supports 43 and 44.

Adjacent to bearing block 52 and fixed to the shaft 55, I have arranged a sprocket 55, adapted to receive a drive .ch ain 5.6, driven by a sprocket 51 mounted on a shaft 53, which is in turn journaled in a bearing block 59 on hearing support .44, and a bearing block 99, fixed to an extension angle fiI, arranged between the upright 24 and the cross member 40.

The outer end of the shaft 53 carries a sprocket 65, adapted to receive a primary drive chain 66 connected to a. sprocket 6], which is driven by a shaft 63 from a motor 69 through a gear box Ill. The motor 69 is supported on a suitable support I I, composed of angles which may be fixed to the frame floor member 22 as by welding.

Thus it may be seen that through the motor 69, chains 65 and 56, with their associated sprockets, incoming floor chains 45 and 46 may be driven to bring a stack of boxes into the machine.

It is customary to stack fruit boxes such as are used for oranges, lemons, grapefruit, et cetera, in stacks of from 6 to 9 boxes. The stacked boxes are permitted to stand for several hours before processing. The chains 45 and 4G serve to bring the stacks of boxes from the place of storage.

Th supplemental elevating chains, indicated generally at I3, consist of a. pair of chains "I5 and I5, supported at their outer end by Sprockets TI and -18, mounted on a shaft I9 journaled in bearing blocks-8B and BI, mounted, respectively, on the bearing support angles 43 and 44.

The shaft 'I 9 also supports the pivotal end of chain support frames, indicated generally at 85 (Fig. 4). The frames 85 are supported by hearing plates 85 and 81. Each frame 95 is composed of two sidemembers. Each side member consists of an upper angle member 88 and a lower angle member 89. At their free ends the angle members 8'8 and 89 engage a bearing plate 90 in which is journaled a shaft 9|, which supportssprockets 92 which, in turn rotatably support the inner ends of the chains I5 and I6. The side members of the frame 85 are held at their inner ends in Spaced relation by a cross angle 93. Roller stops 94, fixed to the plates 9!], limit the inward movement of the stack.

The frame 95 is adapted to be moved into an upper and lower position and is retained in these positions by the action of cam members 95, as shown in Figs. 4 and 11. The cams 95 are eccentrically supported on a shaft 96 which is journaled in bearing blocks 91 and 98, fixed to bearing support members 43 and 44. The cams 95 are notched as at IIIU and HM, these notches being adapted to receive rollers I02, fixed to the upper frame angles 88 by a shaft I03, the outer end of which is journaled in a side plate I I14. Thus it may be seen by a rotation of cams in a manner to be later described, the frame 85, together with the chains I5 and I8, may be raised and lowered to position as shown by Figs. 5 and 6.

The drive for the elevating chains I3 consists of a motor I06 and a gear box III'I, mounted on the support II. Through the gear box IU'I the motor I06 drives a shaft I06 and a sprocket I09 (Fig. 2) The sprocket I09 receives a chain III] which passes over a sprocket IIII on a shaft III. The shaft II I is journaled in bearing blocks H2 and I I3, fixed to bearing supports 43 and 44.

Adjacent to the bearing block I I3, the shaft I I I carries a sprocket II4 which supports and drives a chain H5. The chain Il5 engages a sprocket I I6, fixedto the shaft SI, which, :as has been previously mentioned, supports th inner ends of chains I3.

Another sprocket I20, also mounted on the shaft III, is engaged by clutch drive chain vI2I. The chain I2I also engages a sprocket I22 on shaft 96 and is adapted to drive the rotating portion I23 of a clutch, the fixed portion of which is indicated at I24.

An angle support I2'I (Fig. 10), fixed between the cross member 43 and the bottom frame member 33, supports a bearing block I28 whichsupports a shaft I23. The shaft I28 sup-ports levers I29 and I30, so placed as to'be rocked by a stack of incoming boxes. The lever I29, through extension I,3I, Figs. 1 and 2, is adapted to operate an electrical switch I32, the operation of which will be later described.

The lever I39 includes an arm I33 (Fig. 10), connected to a rod I34. Therod I34 is connected. to a cross arm I35 mounted on a pivot I34. The cross arm includes a clutch stopping member I33 rigid on the arm I35. When the cross arm is rocked it releases the member I36 from engagement with the clutch I24. The cross arm I35 at its upper end is connected to a rod I3'I which is in turn connected to a lever I38 which has an arm I39 thereon. The arm I39 is a clutch stopping member. This member I39 is positioned to stop the rotation of the shaft after a half turn has been made.

To insure this half rotation, I have arranged on the shaft 96, adjacent to the bearing block 9.8, an arm I42 (Fig. ,4) which c ries a pair of rollers I43 and I44 at its outer end, These, rollers 643 and I44 are adapted to engage in a notch I45 in an arm I46, pivotally supported as at M! to a bearing block I48 fixed to the bearing support angle 44.

The notch I45 is held in engagement with either roller I43 or I44 by a tension spring I49, connected atone end to the outer end of the arm I43 and at the other end fixed to the bearing support 44 at its downward jog 45.

The lowerator apparatus, indicated generally at I4, consists of a pair of opposed plates I55 arranged on each side of the aparatus between the upright support members 23 and '25, 24 and 26, respectively. Inasmuch as the two sides of the lowerator mechanism are identical except for being rights and lefts, only one set of reference numerals will be used, thus avoiding unnecessary confusion. For simplicity, the lowerator associated with left plate I55 has been shown in detail and will be dscribed,

The plates I55 rotatably support at their four corners rollers I56 which are adapted to engage and roll against vertical guide shafts I51 and I58 fixed between said supports 35 and 38 at their tops and lower angles 29 and 30 at their bottoms. The plates are movable from their upper position as shown in Fig. 7 to the extreme lower position as shown in Fig. 6 by means to be later described.

A shaft I60, journaled in bearing blocks I6I and I62 fixed to the plates I55 as at I63, supports a pair of stack supporting arms I64 and IE5. The outer ends of the arms are connected by a stack engaging member I66 as by welding. A spring rod I61 pivotally mounted as at I68 on the stack engaging member I66 passes through the plate I55 and is surrounded by a compression spring I69. The inner end of the spring I69 engages the plate I55 and the outer end engages a flange I on the spring rod I61, normally urging the stack engaging member I66 to the position shown in Fig. 5.

At the outer end of the shaft I60 I have arranged a crank "I (Fig. 4) which rotatably supports a roller I12 which, upon upward movement of the plate I55, is adapted to engage a cam lever I15, thus moving the arm "I and the stack engaging member I66 to the position as shown by Fig. '7 to engage the lower end of a stack of boxes B.

The cam lever I is pivotally supported at I16 to a support angle I11 fixed to the frame member 26. Angle I11 also suports a spring backing plate 518, the rearward side of which pivotally supports, as at I19, an emergency switch actuating lever I80 which has a protruding switch actuating arm I3I thereon. A switch actuating rod I82 is slidably mounted in the plate I18, having its outer end fixed to the lever I80 and its inner end rotatably supported as at I83 to the cam lever I15, and is surrounded by a compression spring I84. A switch I85 is fixed to the member 25. Thus it may be seen that if the box engaging arm I66 is unable to engage the lower edge of a stack when the roller I12 strikes the cam lever I15, the rod I82 will be moved, thus moving the lever I80 and the arm I8I, opening the switch I85 and stopping the machine in a manner to be later described in detail.

It is often necessary to align the individual boxes in the stack before they are unstacked. To accomplish this action I have arranged arms I90 pivotally supported on the shaft I60 with an extension I9I at their lower end. The extension I9I is engaged by a compression spring I92, arranged between bosses on the plate I55 and the extension arm I9I, which normally urges the arm I90 to the position shown in Fig. 6. A box engaging member I93 is fixed to the upper end of the arms I90 as by welding.

A roller support member I94 is fixed on the rear of the arm I90 and rotatably supports a roller I95. Upon upward movement of the plate I55 the roller I95 is adapted to engage a cam lever I96 which is pivotally supported at I91 to an angle frame I96 which in turn is fixed to the mid support member 36. A compression spring I99, arranged between the cam lever I96 and the angle frame I98, normally urges the cam lever I96 to the position shown in Fig. 5, the lever I96 being held against further extension by a limit rod 200.

Thus it may be seen that upon upward movement of the plate I55 the roller I95 will engage the lever I96, moving the arm I90 to the position shown in Fig. '7, thus aligning the lower box in the stack. If, as sometimes happens, the box being aligned is wider than normal, the

springs I99 will be compressed, still aligning the box.

The lowerator driving mechanism I5 consists of a motor 205, connected by means of a gear box 206 to a shaft 201, which supports a sprocket 208 and drives a chain 209. The chain drives a sprocket 2I0 mounted on a shaft 2i I. The shaft 2II is journaled in bearing blocks 2I2 and 2I3 (Fig. 2), fixed to the rear vertical support frame members 25 and 26. Fixed adjacent to the outer ends of the shaft 2| I, I arrange a pair of rotating arms 2I4 and 2I5, the outer ends of which rotatably support chain rollers 2I6 and. 2". The rollers 2I6 and 2I1 engage lowerator chains 2I8 and 2I9. One end of each of the chains 2I8 and 2I9 is fixed as at 220 to arms 224 which are fastened at their lower end to the plates I55 at 222. A spacer 223 (Fig. 5), arranged between the plate I55 and the arm 22I, braces the arm 22 I. Each of the chains 2I8 and. 2I9 extends upwardly and passes over sprockets 225, mounted on a shaft 226 journaled in bearing blocks 221 fixed to the upper side of the mid angle frame members 35 and 36.

The chains 2I8 and 2I9 continue rearward over pulleys 228 and 229 on the shaft 2 and around rollers 2 I6 and 2I1 and have their inner ends secured as at 230 to the mid angle members 35 and 36. Thus upon rotation of the arms 214 and 2I5 the chains 2I8 and 2 I9 will be moved in such a manner as to raise and lower the plates I55 as previously mentioned.

The means indicated generally at I6 for secur ing and holding a stack of boxes in a raised position includes a pair of angle securing members 235 and 236 arranged between the forward upright frame members 23 and 24. These members 235 and 236 each have a face A to engage the outer face of a box and a face A to engage the ends of a box. The faces A may be lined with rubber or a like substance, as shown at 231, for greater gripping effect.

The members 235 and 236 are rotatably supported as at 238 by arms 239 and 240 (see Fig. 2) The inner ends of the arms 239 and 240 are rotatably fixed to bearings 24I which have substantially vertical axes. Each bearing 24I is in turn rotatably mounted on a shaft 242 which has a horizontal axis. Thus a substantially universal mounting is provided for the arms 239 and 240.

The upper ends of the angles 235 and 236 are supported as at 243 by a rod 244 (see Fig. 4), which is slidably mounted in a boss 245 protruding from an angle 246. The use of the rod 244 will be later described. Springs 241 and 248 normally hold the rod 244 in the position shown in Fig. 4. A pivot rod 250 (Fig. 2) extends downwardly through each bearing I at the upper ends of the arms 239 and 240. The rods 250 terminate at the lower end in a boss 25I mounted on a spacer 25I' fixed to an angle member 252' secured to an extension arm 252 which latter extends downwardly from the bearing 24I. The rod 259 rotatably supports one end of a brace 253, the other end of which is fixed to the arms 239 and 240.

Thus it may be seen that the angle securing members 239 and 240 are adapted to be moved either horizontally or vertically about the vertical shaft 250 and the horizontal shaft 242 to the desired position. It will also be seen that a downward motion of the seeming members 239 and 240 will also bring them rearwardly and in close contact with a stack of boxes. retaining 7. them .in :a raised position, the'purpose of which will be later described.

.Inbrder to provide .for the -lateral movement of the .entire stack securing :apparatus l8 as a unit to xcompensatefor'any misalignment of the boxes in the stack, I.have arranged a series of flexible pivots to support a floating backing plate 260. Pivotally supported'as at 26| (Fig. 2) to the upper :cross angle member 131, I have arranged arms 252, the lower ends of which are pivotally mountedto the angle 235 which forms the'upper stiffening member for the plate 250. These arms 252 are in vertical spaced relationship, with I only one shown. Pivotally supported by the horizontal edge of angle 246 as at 232, I arrange a second set of braces 26.3 and 2E4, the outer ends of which are pivotally mounted as at- :255 to the central portion of the upper angle frame memberszi and 28. Another set of braces -ZSE and Z-S-T (below the braces :233 -and254) are pivoted at 282" to a brace member 268 and at the lower end of plate 23%) and toblocl: fixed to the upper surfaces of mid angle- members 235 and 236. This movable plate 269 further includes vertical brace angles 270 andill and .a lower central brace 2'52. Between the members 226 and '21! I have arranged a shaftZlI-i, the use of which will be later described.

From the upper ends of the vertical franc members-25 and 2G, I have arranged braces 215 and 216 which support a fixed guide plate 27?. As a further guide I havearranged tubular supports 218 and 219 which extend upward from the horizontal frame members 2? .and 28 and tubular members 288 and 28! upward from the braces 23-5. A horizontal tubular member 2532, as shown in Fig. 3, connects the tops of these brace members.

Referring now to the mechanism indicated generally at IT for controlling the securing mechanism: The shaft 25! acts as a central control from which a pair of cams 235 and 285 (Fig. 4) operate. These cams are adapted to engage rollers 2B? journaled in brackets 283, which are in turn fixed to the extension arm 252 depending from the shaft 242 to cause the securing means to move upwardly. The cams 235 and 285 are also adapted to engage a pair of rollers 2852 (Figs. 2 and .4) journaled in brackets 29.3 which are in turn fixed to upper extension arms 23L The arms 29| extend rearwardly from the shaft 252 and are fixed to the journal of the boss 24 l. Thus it may be seen that engagement of the rollers 235 and 286 with the rollers 28e'will cause the securing means Hi .to move inwardly to engage and hold a stack of boxes.

Should the lower box in a stack .being engaged be slightly wider than normal, I have provided a compression spring 295, positioned between the upper rearward end of the extension arm 29| and the inside center of a U-shaped support 298. The support 238 has its inner lower end fastened as by welding to the lower extension arm 252. A rod 291 retains the spring 295 in the desired position.

Shaft 2|| also carries a pair of switch cams 300 and 38: (Fig. 4), adapted to operate switches 30.2 and 393, the purpose of which will be later described. The switches 332 and 303 are mounted on a bracket 364 which is fixed to the upright frame member 26.

To adjust the securing apparatus l6 so that the bottom box of a stack of boxes is at the center of the unstacker, I have provided an aligning mechanism consisting of a pair of adjusting cams 335 and 130.6 (FigS...9 and 13) fixed to the shaft 2| The cams 305 and .396 areadapted to nga a protrudingtab 30?, carrying a cam 306and fixed to a bracket 308, which is in turn fastened to the cross member 212 of the floating backing .plate 25.). As the stack of boxes is -unstacked, this aligning-mechanism adjusts each lowermost box to acentral position in the machine, thus allowin for much misalignment in th -original stack.

To provide for the outward movement of the securing angles 235 and 238 after the last box of the stack has left the machine and to clear the way for anew stack, I have mounted a roller bracket 3 IE (Figs.-4 and 3) on the shaft 2| I. The bracket supports a roller 3 which may engage adepending section3|2 of an actuating lever 3 I3. The lever 3 I3 is pivotally fixed as at? 4 to a chain uide 3| 5.

The chain guide :3|5, through a boss 3|6, is attached to a collar 3H fixedon the shaft 242. The chain guide 3|5 has a channel 3|8 through which a chain 3 [9 passes. Each end of the chain 3|9 is fixed to an arm 323. The arms 320 are fixed to the arms 23!! and 249 of the securing apparatus It. A rod 32| slidably arranged between the ends of the arms 32!] and vcarrying compression springs 322 terminated against bosses 323 serves to return the securing angles 2.35 and 236 to their normal .closed position. Thus it may be seen that upon engagement of the roller 3| with the member 3 |2 and the lever M3 the chain guide 3|5 will be turned, tightening the chain 3|9 and opening the securing angles 235 and 236 to the position shown in Fig. 1.

The shaft Elli arranged between the vertical plate members 210 and 2H carries a collar 325, from which depends a switch lever 326 (Figs. 4, 9 and '10) The lower end of this switch lever is bent back against itself to form a box engaging section 321.

A switch lever 336, also fixed to one end of the shaft 21.3, is adapted to operate a switch 334 mounted on oneof the backing plate stiffening members 2' when the box engaging section 32-? of the arm 326 is depressed by the lower box of a-stack. The purpose of this switch 331 will be later described.

Another lever 335, mounted on the shaft 213 adjacent to the arm 32$, has its upper end in position to contact a stop extension member 336 on the forward side of the lever 3|-3. A tension spring 331, fxed between the lever :33? and the arm 3|3, normally urges the two together. A second tension spring 338, fixed between the lever 335 and a brace 339, normally urges the lever 329 to the position shown by Fig. 4. The brace 339 is fixed as by welding :to'the cross stiffening member 2T2 of the plate 269.

Thus it may be seen that as long as the lever 32% is held in a depressed position, the lever 3|3 and its depending top 3|2 will be held out of engagement with the roller 3| I,, thus leaving the securing angles 2'35 and 233 in their inward position to engage the lower box of a stack.

As a timing mechanism to vdelay the operationof the clutch i 24 and the subsequent lowering of the chains I3, I have provided a stop lever 342 (Fig. 10), adapted to engage a roller 343 journaled in one end of a crank 344 .pivotally secured to the brace 2-90 as at 345. The outer end of the crank 344 is fastened .to a pushrod 346 at 347. The lower end of the push rod 346 is fixed as at 348 to a lever 349 fixed to a shaft 35.0 journaled in a bearing block 35I fixed to the upright frame member 25.

The shaft 356 carries a two-way crank 352. The upper end of the crank 352 engages a lock member 353 of a lever 354, pivotally mounted on a shaft 355 which is journaled in bracket 356 secured to the upright frame member 25. The outer end of the lever 354 carries a roller 35'! which is adapted to be engaged by a cam plate 358 (Fig. 2) fixed to the pivotal shafts supporting two of the rollers I56 on the plate I55 as at 359. The lower end of the crank 352 is connected by means of a rod 366 to the lever I38 of the clutch control mechanism as at 36!. Tension springs 362 and 363 adjacent the clutch mechanism normally urge this mechanism to the position shown by the solid line of Fig. 10.

Thus it may be seen that even though the lever 342 is moved out of engagement with the roller 343, the clutch mechanism I24 cannot operate until the plate I55 has descended far enough to cause the cam plate 358 to engage the roller 35! to unlock the lock member 353, allow ing the clutch mechanism to operate.

As a safety measure, levers 365 and 366 (Fig. 4) connected at the outer ends by a cross mem ber 36? and pivotally connected as at 368 to bearing blocks 369 fixed to the bearing angle member 46, have been placed in such a manner as to intercept an outgoing box. An L-shaped arm 316, dependent from the lower end of the lever 366, engages one end of a spring 35!. The other end of the spring is fastened to a switch 312 which is fixed to the bearing support 44. The operation of the switch 312 will be later described.

The outgoing conveyor indicated generally at I8 includes a pair of chains 383 and 38!, carried by sprockets 382 and 383 fixed to the shaft III and; driven by the motor I66. The chains are also carried by sprockets 384 and 365, rotatably supported on the outer ends of the shaft 96. The upper reach of the chains 386 and 38I is somewhat lower than the upper reach of the incoming chains I2 or the supplemental chain I3, as shown in Fig. 4. The upper portion of the chains 386 and 38I is supported by chain guides 386 and 381, fixed by means of brackets 388 (Fig. 2) to the bearing support members 43 and 44. Chain guides 369 and 396, fixed to the bearing support members 43 and 44, support the lower travel of the chains 386 and 38L Cam members 36!, fixed to the outer edges of the supports, serve to cam the levers I65 from beneath the lowerbox, as will be later described. :An outgoing belt type conveyor 365- may be used to-convey the individual boxes from the machine. 7 r

-- -Mounted on the bracket364, I provide a third switch 466, adapted to be actuated by a cam 46! on the shaft 2H. This switch 466 is connected in line with a limit switch 465. This limit switch 465 is operable by a pressure lever 466 above the chains 380 and 38I and pivotally mounted by means of levers 461 and 468 to the floor angle 26. A spring 469 normally urges the pressure lever 466 to the position shown in Figs. 1 and 2.

As a safety feature I have provided vertical rods 4I2 (Fig. 4), fixed between the base angles 29 and 30 and the top frame members 21 and 28. The rods 4I2 support three box engaging levers M3 in such position as to engage the lower three boxes of a stack. Adjacent to the lower end of the rods 4I2 I provide a switch lever 4 I4, adapted to actuate a switch 4I5 mounted on the floor frame member 2|. Thus it may be seenthat a 10 box too wide or too badly out of line to enter the machine will trip this switch and stop the operation of the entire machine.

In operation, and referring particularly to the wiring diagram of Fig. 12, a stack. of boxes from 6 to 9 high i brought into the apparatus on the feed conveyor I2. The lowermost box strikes the switch lever I 36 which causes the clutch I24 to operate, thus raising the chains I3 and depressing lever I23, engaging switch I32 to stop the motor 63. The stack continues into the machine until the roller stops 64 are engaged. At this point the second box from the bottom of the stack engages the portion 321 of the lever 326, closing the switch 331 and starting the motor 265, which continues in'operation until the last box clearsthe lever 326, opening the switch 33 I.

The depressing of lever 326 also moves the arm 335 from engagement with the stop 336, allowing the tab 3 I 2 to disengage from the roller 3I I, causing the securing angles 235 and 236 to engage the second box from the bottom of the stack. The parts are so arranged that the faces A first engage the outer face of the box and pull the box towards the floating plate 266 to align the en gaged box. Thereafter further movement of the member 235 and the member 236 causes the faces A and also the faces A to tightly hold the box which they engage. The cams 285 and 286 engage the rollers 289, further increasing the pressure on the securing apparatus I6. At the time this securing operation takes place, the plates I 55 travel downward to the position shown in Fig. 6, allowing the cam plate 358 to engage the roller 351 and, by means of the linkage previously described, lower the chains I3. The lowermost box is thus deposited on the outgoing chains I8 to be conveyed from the machine.

The plates I55 continue upwardly until the outward extension of the arms I64 and the cross members I66 engage the bottom of the lowermost box of the stack, raising it slightly and thus aiding the release of the securing apparatus I6, which is completely accomplished by engagement of the cams 285 and 286 with the rollers 281. The stack is positioned in the center of the machine at this time. This position is illustrated by Fig, '7.

The plates I55 then continue downwardly, car'- rying the complete stack. At a point near the bottom of the travel, the holding apparatus engages the next to the bottom box to hold that box and those boxes above it while the bottom box continue downwardly to be deposited on the outgoing conveyor I8, the arms I65 being carried out of the path by the cams 39L This operation continues until, all the boxes have been unstacked, whereupon the securing angle 235 and 236 spread apart and the machine comes to rest pending the arrival of a new stack into the unstacker.

Should the boxes fail to clear the machine at a suflicient speed to keep the conveyor 395 full, the switch 465 and the switch 406 will be both opened, causing the machine to be stopped in the position shown by Fig. 8.

The switch 3I2 is adapted to stop the motor I06 and the outgoing conveyor should a box be broken or be too low to clear the machine.

In the foregoing description I refer to my invention as employed in a manner wherein single boxes are removed one by one from the bottom of a stack and in which the holding means engages the next to the bottom box of the stack. It will be understood, however, that this holding means may engage the third box from the bot- 1 l, tomof; the stacker other boxes so that the boxes may be dischargedfrom the stack'in tiersof two or-in; any other arrangement. desired. Although I have described the apparatuses removing boxes singly, it willbe understood that with equ-alfacility, t'heapparatus can remove more than one box from the bottom of a stack;

Haying thus. described my invention; and the presentpreferred embodiments thereof I desire toemphasize the fact that many modifications may be resorted to in a manner, limited Only by a just interpretation of the, followingv claims, wherein;

I-Iaying thusdescribed my invention; I claim:

1 ,Ir i a boxv unstacking apparatus, anunstacking station, a feed conveyor adapted to feed'boxes t o th e .unsllfi cking station, vertical guide members disposed at, each side, of the station, plates mounted -toinove up and down onthe guide memb,e 1:s, a chain, connected, at, one side to each of the, platesa sprocket aboveeach plateand receivinga chain, a crank, member at one side of each sprocket, each crank member having a roller thereon, each chain passing one of the rollers, means to anchor the other end; of the cl ains, means to rotate the crank member to raise and lower the plates, and a box supporting member mounted on each plate; each box'supporting member. having a. box engagingpart' thereon adapted to engage beneath a box at the station;

2: In a box unstackingapparatus; an unstackiing .station-, a feedconveyor adapted tofeedboxes to ,the unstackingstation, vertical guide members disposed". at each, side of the station, plates mounted to moveup and down'onthe guide membeILS. achain connectedat' one endto each of. the plates, a sprocket above each plate and receiving a, chain a crank member at one side of each sprocket, each crank member having, a roller thereon each, chain passing over. one of the rollers, means, to, anchor the other end of'jthe chains; means to. rotate' the. crank ,member' to raiseand. l wer the plates, a box supporting memher having a box engaging part thereon adapted to .engage beneath a box at the station; andmeans to ve saidboxengasing p s p t to pe m delivery of a, stack of boxes tothe receiving sta ion.

3. VA, jbox unstacking mechanism including a frame, .a pair, of; substantially vertically extending, an le. shaped; b x. se ringmembers, e c m mb r har ngracesadap edt eneasethe front faceiandn he ndia e of. a a s pport r pivoted at its outer endfin ea ch 'of the securing memb r s id. arms, beingirearwardly directed; pivotei upp rtingmeans on the, frame ands m pbrfinafihe. inn r end'siofgr aid arms, a cam.- onerabletomove thesecuringmembers towardsthe ends of'boxes in a stack, andacam operableto movelsaid arms ,rearwardly against a. .box inhthe s ack,

4,, A .box unstacking mechanism, including a frame, a backing plate, 'means mounting the backing plate on the frame for transverse movement, in a substantially vert ical plane, a pair of substantially vertically extending angle, shaped securing ,members, each member having faces adapted to engage the. front face and the end faceiof abox, aysupporting arm pivoted to each ofgthesecuring members for movement about a horizontal" axis, said arm being upwardly and rearwardly inclined, universal supporting means on,. the,frameand supporting the inner ends of saidarmsta lever disposed. to bevrocked b'y the secondbox from the bottom of'a stack in the apparatus; cammeans operable by said lever to move the securing members towards the-ends of boxes-in the stack, and other cammeans to move said arms downwardly'to movea box engagedby the arms rearwardly'against the backing plate.

5. A box unstacking mechanism including a frame; a backing plate, means mounting the backing plate on the frame fortransverse movement in a substantially vertical plane, a pair of substantially vertically extending angle shaped securing members, each member having faces adapted to engage the front face and end face of a box, asupporting armpivoted at its outer end on each of the securing members for movement: about a horizontal axis, said arms'being upwardly and; rearwardlyinclined and having bearingsattheir inner ends, said bearingshaving their; axes substantially vertical, a horizontal shaft at the, inner endof'said arms, each of said bearings" being rotatably mounted onthe horizontal shaft to provide a substantially universal mounting for the arms, a pivot rod extending downwardly through each of the first mentioned bearings, each pivot rod terminating at its lower end in a boss, an extension armextending downwardly from each of the'second mentioned bearings, an angle member connecting said extension arms, spacers on the connecting angle member, said bosses being mountedon' said spacers, upwardly inclinedbraces each having one end en'- gaging a boss and rotatable with the pivot rod, the other end of each of said last mentioned braces being'connecte'd' to-one of the supporting arms adjacent to the lower end of the latter, a lever disposed to be rocked by the second box from the bottom of a stack in-the apparatus, cam means operable by said l'ever'togmove thesecuring members about the axis of thefirst mentionedbearings towardsthe boxes in the stack, cam means to-move said arms about their horizontal axes downwardl'yto cause'the facesof the supporting members whichengage the front face of thebox to move an engaged box rearwardly against the backing plate, and other cam means to move said arms towards each other about their vertical, pivots to engage and support the box.

6; A box unstacking mechanism includinga frame, a backing plate, means mounting the backingplate on'the frame, for transverse movement in a substantially vertical plane, a pair of substantially vertically extending angle shaped securing; members, each member having faces adapted to engage the front faceand the endface of a-box; a Supporting arm pivoted at its outer end on each of the securing members for-move'- ment about a horizontal axis, said arms being upwardly and rearwardly inclined and, having bearings at their inner-ends, saidbearings having-their axes substantially vertical, a horizontal shaft at the inner end of said arms, each of said bearings being rotatably mounted on the horizontal shaft to provide a substantially universal mounting for-the arms, an upwardly and rearwardlyinclined supportinggrod secured; to the upper end of each securing member, aboss on the frame, said boss having an aperture" through which said rodextends, resilient meansnormally urging the rods rearwardly, a pivot rod extending downwardly through each ofthe-first mentioned bearings, each pivot rod terminating at its lower end in a boss, an extensionarm extendingidownwardly from each of the second mentionedbean ingshan anglemember connectingsaid extension arms; spacers on the connecting angle'membei",

said bosses being mounted on said spacers, upwardly inclined braces, each having one end engaging a boss and rotatable with the pivot rod, the other end of each of said last mentioned braces being connected to one of the supporting arms adjacent to the lower end of the latter, a lever disposed to be rocked by the second box from the bottom of a stack in the apparatus, cam means operable by said lever to move the securing members about the axis of the first mentioned bearings towards the boxes in the stack, cam means to move said arms about their horizontal axes downwardly to cause the faces of the supporting members which engage the front face of the box to move an engaged box rearwardly against the backing plate, and cam means to move said arms towards each other about their vertical pivots to engage and support the box.

'7. A box unstacker including a frame, a backing plate, support members engaging the backing plate and frame and mounting the backing plate for lateral shifting movement in a substantially vertical plane, a pair of spaced, substantially horizontal, parallel brace members, means pivotally mounting the inner ends of each of the brace members to the backing plate for movement about substantially vertical axes, and means pivotally securing the forward end of each of said brace members to the frame for movement about substantially vertical axes.

8. A box unstacker including a frame, a pair of spaced depending arms, means pivotally mounting the arms on substantially horizontal pivots to the frame, a backing plate, means pivotally mounting the lower ends of said depending arms on the backing plate, a pair of upper, parallel, spaced, substantially horizontal brace members, means pivotally mounting the inner ends of the brace members to the backing plate for movement about substantially vertical axes, means pivotally securing the forward end of said brace members to the frame for movement about substantially vertical axes, a pair of lower, substantially horizontal, parallel brace members, means pivotally connecting the inner ends of the lower pair of brace members to the backing plate for movement about substantially vertical axes, and means pivotally connecting the outer of the lower pair of brace members to the frame for movement about substantially vertical axes.

9. In a box unstacking apparatus, box securing and holding means including a frame, a backing plate, spaced parallel arms mounted on the frame and pivotally secured to the backing plate to permit lateral movement of said backing plate, a pair of spaced shafts on the frame, a pair of spaced arms, means pivotally mounting the arms on the shafts, a box gripping member pivoted on each shaft thereof, a cam operable to cause the gripping members to move towards each other to engage a box, and cam means to cause the gripping members to move towards said backing plate to move a box engaged by the gripping members against the backing plate.

10. A box unstacker including a frame, a horizontal cross member on the frame, a pair of spaced depending arms, means pivotally mounting the arms on substantially horizontal pivots to the cross member, a backing plate having a horizontally disposed stiffening member at its upper end, means pivotally mounting the lower ends of said depending arms on the stiffening member, a pair of upper, parallel, spaced, substantially horizontal brace members, means pivotally mounting the inner ends of the brace memhere on the stiffening member for movement about substantially vertical axes, the frame including forward extending upper members, means pivotally securing the forward end of said brace members on the upper frame member for movement about substantially vertical axes, a pair of lower, substantially horizontal, parallel brace members, means pivotally connecting the inner ends of the lower pair of brace members to the backing plate for movement about substantially vertical axes and means pivotally connecting the outer of the lower pair of brace mem-' bers to the frame for movement about substantially vertical axes.

11. In a box unstacking apparatus, holding means, a lowerator movable to engage a box held by the holding means, said lowerator including spaced, opposed, vertical guide members, shafts mounted to move up and down on the guide members, stack supporting arms journaled on said shafts, means to cause said supporting arms to move inwardly and outwardly to engage a box of a stack, means to align the lowermost box in a stack prior to unstacking, said aligning means including pivoted aligning arms, and cams operable to move said aligning arms to box engaging position to align a box in a stack.

12. In a box unstacking apparatus, holding means, means to cause said holding means to engage and support a stack of boxes, a lowerator movable to engage a box held by the holding means, said lowerator including spaced, opposed, vertical guide members, plates mounted to move up and down on the guide members, a chain connected at one end to each of the plates, a sprocket above each plate and receiving a chain, a crank member at one side of each sprocket, each crank member having a roller thereon, each chain passing over one of the rollers, means to anchor the other ends of the chains, means to rotate the crank member to raise and lower the plates, means to release the holding means, a delivery conveyor, means to lower the lowerator until the box held thereby is at a location adjacent to the delivery conveyor, means to cause the holding means to engage a box above the lowermost box of the stack being lowered by the lowerator when the lowermost box in the stack being lowered is at said location, and means to further lower the lowerator while the holding means holds the reduced stack to dispose the lowermost box of the stack being lowered onto the delivery conveyor.

13. In a box unstacking apparatus, holding means, a delivery conveyor, a lowerator movable to engage a box held by the holding means, said lowerator including spaced, opposed, vertical guide members, plates mounted to move up and down on the guide members, horizontal shafts supported by each of said plates, a pair of spaced, upwardly inclined stack supporting arms journaled on each of said shafts, a transverse stack engaging member secured to the upper ends of each pair of supporting arms, means to cause said supporting arms to move inwardly and outwardly to engage a box of a stack, means to align the lowermost box in a stack prior to unstacking, said aligning means including substantially vertically directed aligning arms pivotally arranged on said shafts intermediate said supporting arms, a box engaging and aligning member secured to the upper end of each of said aligning arms, cams operable to move said aligning arms to box engaging position to align a box in a stack, a chain connected at one end of each of said plates,

azspmeket aboveeeach: plate-and; adapted, to receive:a chain, a! crank member: at one.- side, oi, andirotatable:with-,; each sprocket, each crank member having-a roller: thereon, reach-chain passing over-one ,ofthe rollers, means to fixedly anohorqthe other endrof the-chains; means tomove the: holding; means to; releasing position, and meansytoizrotate the-crankto lower the lowerator untili the box; held thereby is at; a; location ad- J'aeent. to; the; delivery conveyor.-

14. In--- a.- box"; unstacking; apparatus, holding means; means-to cause: said? holding, means to en ageandrholda'stacleof boxes, aidelivery GOD-r veyor, a lowerator movable to engage-a box. held by; theholding; means, saidilowerator including spaced oppose d; vertical; guide. members, plates nmunteditomovenp andldownpn theguide memhers;,horizontaishaftsr supported: by each of: said platesgapair; of spaced-1 upwardlv directed; stack supporting arms; journaled on each; sidesof said shafts; a transverse stackengaging memberrcone meeting -the upper endsof; each:pair of supporting arms; means; to cause said supporting, arms to move-inwardly and outwardly; to; engage a box ofrasstack; means to;align'-,the lowermost-box in azstackprior to unstacking said aligning means including substantially vertically: directed align.- ing arms; pivotally, arranged on said. shafts intermediate saidsupportingarms, abox engaging and aligning; member secured: to: the upper end 116 of said. arms, cams operable. to move said aligning arms to box engaging position to align abox in-.a stack,,a chainlconneoted at, one. end ofweach of said, plates, asprocket above each plate and adapted to receive a chain, a crank member at onefside of, and rotatablewith, each. sprocket, each: crank member having aroller, thereon, each chain passing over one ofv the rollers, means, to fixedly anchor the other endof the chains, means to move thev holding, means to, releasing position, and means. to rotate the crank ,to, lower the lowerator until thebox held thereby is at. a location adjacent to-the delivery conveyor.

AMBROSE A.. NEJA.

REFERENCES CITED The following; references are; of record; in the file of thispatent:

UNITED STATES PATENTS Germany Apr. 11, 1927

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