US1651791A - Lifting fork - Google Patents

Description

Dec. 6, 1927. 1,651,791

w. yv. WALLACE LIF'TI NG FORK Filed'Feb. 4. 1926 4 Sheets-Sheet 1 Dec. 6,'1927. 1,651,791

W. w. WALLACE LIFTNG- FORK Filed Feb. 4, 1926 4 Sheets-Sheet 2 ,ze 19 J8 zz ,z

Dec. 6, 1927.

W. W. WALLACE LIFTING FORK Filed Feb., 4f., 1926 4 Sheets-Sheet 5 Wmllhm. NMIY hh Invair '02 ,6M

25 deliver the unit of 45 vention,

50 ation.

WILL W. WALLACE,

1 BLING COBYOBATION, OF NEW YORK, N.

or CHICAGO, ILLINOIS, essienoa 'ro New Yoan Barok Y., a CORPORATION or' Naw Yoan.

LETNG FORK.

v Application med February 1926. Serial No. 85,968.

My present invention relates to lifting devices and more particularly to an. improve loading and dumping fork for use in connection with the mechanical handling of brick.

te In the handlinff of brick by mechanical means, it is desira le and, in fact, necessary that the bricks be handled in units, such units bein of any desired size. These units are usua ly built up after the preliminary drying operation on the brick and are then brought by a lifting fork into position where they are built into a kiln. The kiln is afterwards burnt and the completely burnt brick are removed from the kiln in units by aplitting device and carried to a truck, car, barge or any desired delivery device. With further improved methods of manufacturing brick,

v it has been found desirable to lift the unitv on afork and when the unit has been brought to the place of delivery, deposit same 1n position and then remove the fork from beneath such unit, thereby depositing and leaving the unit in stacked ormation on the device. For this reason, a lifting fork with lpivoted tines or equivalent device is not necessary and therefore the lifting device may be made considerably more rigid than has heretofore been possible. The units brick are built up upon so called inger courses, between such lingerv courses the tines of the lifting fork are placed. ln former constructions, it was usual to leave the finger courses in position and merely lift that portion of thebrick unit lying thereon.

This practically necessitated lthe dumping of brick o the fork when the same was brought to the point of delivery.

In m present invention I have obviated the ObJectionable features of prior apparatus of this t pe and the present invention is to be consi ered as an improvement over the fork shown in my Patent No. 1,564,652, dated December 8, 1925. in my present in- I have shown improved means for gripping and holding the individual bricks. comprising the finger courses and am thereby enabled to lit an entirev unit of brick, includin the linger courses, at a single operhave devised any entire gripping means whereby the finger courses are positively held on yielding tension, the tension depending upon the weight of the unit of br1ck so that the greater the weight of the brick, the greater the tension on the holding means. y

The principal object of my invention, therefore, 1s an improved brick lifting fork. Another object of my invention is an improved brick lifting fork, having in combination therewith, means for gripping nger courses .of a unit of brick.

A further object of: my inventionis an improyedbrick lifting fork, having in combination therewith, an improved means for yleldlngly holding and gripping the iinger courses ofa unit of brick.

Other objects and knovel features of the construction and arrangement of parts comprising my device will appear as'th'e description of the invention progresses. ln the accompanying drawings illustratng the preferred embodiment of my inven- Fig. 1 is apide elevation,

Fig. -2 is a rear elevation,

Fig. 3 is a fragmentary plan elevation of a device showing the gripping fingers in operative position,

Fi ,4 is a fragmentary plan view similar to Fig. 3 but withthe gripping fingers in inoperative position.

Fig. 5 is a sectional side elevation on the line 5-5 of Fig. 4,

Fig. 6 is a fragmentar sectional end elevation on the line 6-6 o Fig. 2,

Fig. 7 is a sectional plan view on theline 7--7 of Fig. 5,

Fig. 8 is a plan view on the line 8--8 of Fig. 5, and l Fig. 9 is a sectional elevation on the line 9-9 of Fig. 8.

Referring to the drawings, 10 designates a base provlded on its lower face with a longitudinal extending rib pro'ection 11 and se cured to the lower face by olts and nuts12 and 13 respectively are a plurality of parallell. arranged lifting fingers 14, the upper sur ace of the rear end of each of these iingers being provided with a groove that cooperates with a longitudinal rib 11 on the base 10. The rib and groove prevent a rotarymovement of the ngers 14 with respect to the basel 10. The fingers 14 are spaced apart fromv each other a distance slightly greater than the width of two bricks 15, as shown `in Figs. 3 and 4. By possible to slide thefmgers 14 between the this construction, it is to the spring crosshead rows of brick 15,.such brick constituting the finger courses of a unit of brick. Secured t0 the lower rear face of the base 10 at intervals along the length thereof are bearings 16, the bearings being in alignment with each other and rotatably mounted in the bearings is a finger clamp shaft 17 Each of the bearing members 16 are' provided on their lower face with a shaft 18 on which is mounted for rotation an anti-friction wheel 19 to facilitate travel of the ap aratus along the ground or other'place w ere the same is to be worked. Also secured to the shaft 17 at intervals alon its length are crank arms 20, the number o crank arms 20 being equal in number to the fingers 14 attached to the base 10. .Pivotallyl attached to the lower free end of each of the crank arms 20 is one end of the member 21, this member on its free end being internall threaded to receive the externall such t readed end being provided with a lock. nut 23 for holding the member 21 and finger rod 22 in adjusted position. The fingers 14 are hollow and the finger rods 22 are slidably mounted therein, one finger rod 22 for each finger 14. Secured to each of the finger rods 22 by pins 2`4, are collars 25, these collars being arranged in pairs and between each pair and on the rod 22 is a `coiled spring 26, as clearly shown in Fig. 7. Adjacent to one of the collars 25 of each pair of collars i's a spring crosshead 27, each crosshead being provided with radially extending pins 28. There are a plurality 25 on each r0d` 22 and therefore a pluralit of spring crssheads 27 oii each rod 22. side wall of each of the lingers 14 adjacent 27 is provided with a cut out portion 29, and pivotally mounted in each of the cut out portions 29 on pin 30 is a member 31, this member on its inner end be ing provided vwith slotted ears 32, these ears encircling the pins 28 on each side of the spring crosshead 27. To the end of each of the members 31, designated as finger levers, are pivotally mounted finger clamps 33. When the rod 22 is moved to the left, as

shown in Figs. 7 and 8, the pairs of collars 't lward 25 attached thereto, move also to the left, as does the coiled spring 26. The tension of the coiled spring 26 keeps the spring crosshead 27 in engagement with its associated collar 25 and the pins 28 thereon engaging with the ears 32 of the finger lever 31 rotate such finger levers in an anti-clockwise direction around the pin 30, thereby bringing the finger clamps 33 outwardly laterally from the fingers 14 and into engagement with the linger courses l5. The continued movement of the rod 22 to the left will cause the clamping fingers 33 to force the finger courses -15 into engagement with the adjacent finger/14, as clearly shown in Fig. 3, and as the movement of the rods 22 to the left continues, the

y ditions the finger clamp'33 is yieldingly held threa ed end of a finger rod 22,

of pairs of collars -into such spring crosshead 27 will become separated from its associated collar, as'shown in Fig. 8 and it will be obvious that under these conagainst the finger courses 15 by the compres- 70 sion spring 26. l Formed on the base l0, adjacent toeach end of the upper surface thereof are mem# bers 34. To each of the members 34v and on each side thereof, secured by bolts '7 and nuts 35 and 36 respectively, are ver-v tical bars 37. These bars are secured at fil ,their upper euds to the ends 4of a framework designated generally by the numeral 38. Secured to the upper central portion of the base 10 are vertical braces 39 which extend forwardlymas shown in Fig. 2v and are,4 secured to the framework 38, also to the inner -ones of thebars 37. At each end of the framework 38 and extending forwardly therefrom is a memberY 40. vIn each of these'4 members 40 is ,secured parallelly arranged shafts 41 and 42 and on these shafts are rotatably mounted thelevers 43 and 44 respectively. The innerends of the levers 43 and 44 are connected together by means ofv apivotally mounted connecting link 45 and also the inner ends are provided with abutting faces 46 and 47 respectively which prevent too great a rotary movement of the levers 43 and 44 in one direction. Each of the levers 43 are provided at their lower rear ends with an elongated slot 48, in which is slidably mounted a pin 49 'and pivotally mounted on the pin 49 is a downwardly depending member 50. The lower free end of the member 50 is internally threaded to receive the upper threaded end of a connecting rod 51, a. lock nut 52 being provided on the connecting rod 51 for maintaining such connecting rod and member 50 in adjusted position. The lower end of each of the connecting rods 51 is threaded and screws into the upper end of members 53, a lock nut 54al being associated 'therewith for adjusting purposes. Each of the. members 53 is pivotally attached t0 the outer end of crank arms 541 secured to the shaft 17.

The rear ends of the levers 43 and the forends of the levers 44 are provided with pivotally mounted shackles 54 with which are associated shackles 55 pivotally mounted on a lifting platform 56, the shackles 54 and 55, together with levers 43 and 44, constitutinga four point suspension means for the apparatus.

Formed integral with each of the levers 43' and extending upwardly ltherefrom on each side thereof, are 'members 58, these members being spaced apart from each other, as clearly shown in Fig. 8 and provided on their front edges with grooves 59. Fitting grooves 59 are pins 60 formed on cup-shaped holding memside thereof and 13 llO opposite sides of a ber 61. Formed on each acarrea extending forwardly therefrom are ears 62 similar to the ears 58 above described, and on the rear edge of each of these'ears is formed a roove 63 which engages with pins 64, former? on opposite sides of a cup-shaped spring holding member 65.k The open end of each of the spring holding members 61 and 65 is located a compression spring 66, this compression spring, as will be seen from an inspection of Fig. 6, tending to rotate the levers 43 and 44 about their pivot points so as to move the outer free ends thereof downwardly and thus to cause a movement of the rods 22 to the right, as shown in Figs. 7 and 8. In order to vary the tension of the springs 66, I have provided the members 61 and 65 with adjustlng screws 67, the inner end of these screws engaging with .the

springs 66. The weight of the load on the fingers 14 is balanced by the tension springs 66.

The device, as above described, is applicable to the picking up and carrying of a unit of brick by means for yieldingly engaging the finger courses of such unit. It may happen that it will be desired to merely 4lift a unit of brick without regard to the finger courses thereof and I have, therefore, provided means for locking the finger clamps 33 in enclosed or in the inoperative position.

Referring to the drawings, there is shown secured to the top surface ofthe frame 38, bearing standards and in these bearing members is rotatably mounted a shaftv 71. Secured to the rearf end of the shaft 71 is a crank handle 72 and by means of which the shaft 71 may be rotated. Secured to the shaft 71, intermediate its ends, is a fiange 73 and extending laterally outward from said flange, diametrically with respect to each other, are crank pins 74. Pivotally connected to each of the crank pins 74 are connecting rods 7 5, one of each of these connecting rods bein arranged on each side of the shaft 7l, as c early shown in Fig, 2. The other ends of each of the connecting rods 75 are pivotally attached to bars 76 slidably mounted in bearing members 77 secured to the top surface of the frame 38. Each of the sliding bars 76 is provided at the end, remote from the connecting rods 7 5. with U-shaped end members 78 of a size adapted to fit between the cup-shaped spring holding members 61 and 65. It is obvious, therefore, that if the U-shaped members 7 8 are placed `between the members 61 and 65, it will be impossible for such members 61 and 65 to have any movement toward each other, and therefore, the mem bers 61 and 65, being held immovable, the pins 60 and 63 will likewise be held immovable and the ears 58 and 62, contacting with such pins 60 and 63, will prevent a rota movement of the levers 43 and 44 in suc material direction as to have the outer free ends thereof move upwardly. If there can be no upward movement of the outer free ends of the levers 43 and 44 there will "of course be no upward movement of the connecting rods 52 and therefore no movement to the left of the rods 22, as viewed in Figs. 7 and 8. Movement to the left of the rods 22 being prevented, the finger clamps 33 will remain in the' position shown in Fig. that is housed within the limits 14. Therefore, when the locking device just described is utilized, the apparatus may be utilized as a lifting fork to piek up and load on to of the fingers 14, as is the case of the lifting forks heretofore manufactured.

It will be noted from an inspection of the drawings, and particularly Fig. 9, that the upper ortion of the fingers 14 is of considerab e less width than the lower portionI of such fingers. There is considerable advantage` to be obtained in making these fingers in this manner. As is well known, when said machine grips the grip courses, it only gri s the bottom plart of the bricks and, there ore, pinches t ese bricks in so that there is less room in between the rows of the fingers at the top than there is in between the bottom rows of the grip ngers, and, therefore, when taking these brick out with the new fork, forming the subject matter of the present invention, there will naturally be less room for the fingers to get in between the top of the brick courses than there is at the bottom of the brick courses.

While have necessarily shown the preferred embodiment of my invention somewhat in detail, it is to be understood vthat l may vary the size, of arts comprising the device Within wide limits without departing from the spirit of thel invention.

Having thus described 'my invention, what l claim as new is:

1. An im roved lifting fork comprising a plurality o parallelly arranged ngers, piv-l otall mounted means for engaging material ocated between said fingers, a rod slidably 4mounted in each finger and springs on each rod cooperating with the material, and engaging means for yieldingly holding said sition..

2. An improved lifting fork com rising a plurality of parallelly arranged ngers, means associated therewith for engaging material located between the fingers, rods slidably mounted in each nger, springs located on said rods, connecting means between said springs and the material engaging means and means for moving said rods to move the springs into position to yieldshape and arrangement holding means in inoperative poingly hold the material engaging means in l inoperative position.

3. An improved lifting fork comprising a laterally outward therefrom,

base, a plurality of parallelly arranged lifting lingersl secured thereto and extending material engaging means pivotally mounted in saidfingers, means for moving said fingers into engaging position with material placed between the lingers and yieldingly holding the same in inoperative position andl suspension means for said base for moving said rods and yieldingly holding rods in inoperative position. Y v

4. An improved lifting fork comprising a base, a plurality-of parallelly arranged lifting lingers secured thereto and extending laterally outward therefrom, said fingers bes.

area at their portion, ma-

greater crosssectional ing of portion than at the top bottoni l terialv'engaging means pivotally mounted in said lingers, vmeans for moving said lingersinto enga ing position with material placed between t e fingers and yieldingly holding' the same in inoperative position and suspen.

` such fin ers,

sion means for said base for moving said material engaging-means intoinoperative position.

5. An improved lifting fork comprising n plurality of parallelly provided with a longitudinally arranged passage extending throughout 'the length thereof, means associated therewith forv enra ing material located between the fingers and normally housed within the. limits of a rod mounted in each passage and sli'able with relation to the fingers, springs located-on -said rods, connecting means between saidsprings and the mate- \rial engaging means, and means for moving said rods to move the springs into position to yieldingly hold the material engaging` means in inoperative position.

In'testiinony whereof, I have signed my name to this specification. .y

WILLIAM W.. WALLACE.

arranged ngers, each 1

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