US3488080A

US3488080A - Automatic grapple

Info

Publication number: US3488080A
Application number: US715628A
Authority: US
Inventors: Alexander Hamilton
Original assignee: Individual
Current assignee: Individual
Priority date: 1968-03-25
Filing date: 1968-03-25
Publication date: 1970-01-06
Anticipated expiration: 1987-01-06

Description

Jan. 6, 1970 A. HAMILTON 3,488,080

I AUTOMATIC GRAPPLEZ Filed March 25, 1968 r 4 Sheets-Sheet 1 wvimon DER HAMILTON ATTORNEYS ALEXAN 4 Sheets-Sheet 3 Filed March 25. 1968 mvcmon ALEXANDER HAMILTON ATTORNEYS 611970 A. HAMILTON 3,488,080

' AUTOMATIC GRAPPLE Filed March 25. 1968 4 Sheets-Sheet a mvpITbR ALEXANDER HAMILTON.

IY M n'rromusvs Jan. 6, 1970 A. HAMILTON 3,488,030

' AUTOMATIC GRA"PLE Filed March 25, 1968 V 4 Sheets-Sheet 4 ALEXANDER HAMILTON United States Patent 3,488,080 AUTOMATIC GRAPPLE Alexander Hamilton, 4871 Union St., Burnaby, British Columbia, Canada Filed Mar. 25, 1968, Ser. No. 715,628 Int. Cl. 1366c ]/62, 3/10 US. Cl. 294110 13 Claims ABSTRACT OF THE DISCLOSURE Grapple apparatus having a plurality of grapple elements mounted on a supporting member and being weight operated to swing to a normal open position. The grapple elements are movable to a closed position by the operation of a lift rod which may be selectively connected to or disconnected from a hoisting cable through the mediacy of a pair of latching elements pivotally mounted on a carrier and movable into and out of latching engagement with the rod. The carrier which is slidably mounted for limited movement on the supporting member and connected to the hoisting cable may be slidably positioned in selected positions by appropriate slackening of the hoisting cable to bring the latching elements into operable engagement with an operator slidably mounted on the rod.

Background of the invention This invention relates to lifting equipment and more particularly to such equipment employing tongs or grapple elements which, when suspended by a hoisting cable, may be used for gripping lifting and depositing logs and the like in a purely automatic manner.

In view of the heavy and unweildy loads handled, par ticularly in the logging industry, the need for grapple equipment which may be operated without the employment of extra operators or cable for manipulating them has resulted in the development of many and varied automatic devices. Many of these devices employ magnets and similar operator controlled mechanisms for operating latches and the like whereas other devices are purely mechanical in nature and may be automatically operated between gripping and nongripping positions by appropriate movements of the hoisting cable on which they are suspended.

Devices of the last mentioned type, of prior design, have usually required operating elements which are in exposed positions and are therefore subject to snagging and fouling. Furthermore, devices of this nature have in the main, been unduly complicated in design and therefore very costly to manufacture and maintain.

Summary of the invention The present invention provides a grapple type lifting apparatus which may be operated between gripping and nongripping positions by manipulation of the hoisting cable on which the apparatus is suspended without the use of any extraneous devices.

The grapple apparatus of the present invention, furthermore, is so designed that its operating mechanism is, in the main, completely hidden and is therefore not subject to fouling or jambing when used under adverse conditions.

The apparatus of the present invention is, furthermore, not of complicated design, has very few working parts and is therefore relatively inexpensive to manufacture and very easy to maintain.

The present invention comprises a carrier member connectable to a hoisting cable, a supporting member having a vertical slidable connection with the carrier member, upper and lower stops on the supporting member engageable by the carrier member for limiting the relative vertical 3,488,080 Patented Jan. 6, 1970 movement of said members, a pair of grapple elements swingably mounted on the supporting member for movernent between open and closed positions, weight means actmg m the grapple elements when the supporting member is supported by the carrier member for swinging the grapple elements towards an open position, a lift rod connected to the grapple elements being adapted when connected to the carrier member to operate the grapple elements toward a closed position, latching means swingably mounted on the carrier member engageable with the lift rod for operably connecting the latter and the carrier member and a cammed operator slidably mounted on the lift rod engageable by the latching means upon predetermined selective movement of the carrier member relative to the lift rod for swinging the latching means into and out of latching engagement with said lift rod.

Brief description of the drawings FIGURE 1 is a front elevation of one embodiment of the invention suspended from a cable with the grapple elements in an open position, and having portions removed for purposes of clarity of illustration,

FIGURE 2 is a sectional view taken along line 2-2 of FIGURE 1,

FIGURE 3 is an enlarged view of a portion of the inven tion as illustrated in FIGURE 1,

FIGURE 4 is a sectional view taken on the line 4-4 of FIGURE 3,

FIGURE 5 is a view similar to FIGURE 1 with the apparatus at rest over a log,

FIGURES 6 and 7 are enlarged views of a portion of the invention in various operational positions,

FIGURE 8 is a front elevation of another embodiment of the invention,

FIGURES 9 and 10 are front and side views, partially in section, of yet another embodiment of the invention, and

FIGURE 11 is a sectional view on line 11-11 of FIGURE 9.

Description of the preferred embodiment Referring to the draiwngs and in particular to FIG- URES 1 to 4 thereof, there is illustrated one embodiment 10 of the invention. Grapple 10 comprises a supporting member of frame 12 formed of a pair of

cheek plates

13 and 14 which are arranged in fixed spaced apart parallelism by means of spacers 15 and bolts 16. The

cheek plates

13 and 14 are somewhat elongated in a vertical direction and support a pair of grapple elements or tongs 17--17, the tongs being pivotally mounted on pins or bolts 18 which extend transversely between the cheek plates.

These pins or bolts 1818 are a type well known in the trade which have an eccentric rotatable central shaft portion upon which the tongs are mounted so as to obtain a degree of relative lateral movement of the latter. The degree of eccentricity ofthe pins or bolts 1818 is such as to permit pivotal movement of the tongs between an open position as illustrated in FIGURE 1 and a closed position about a log or any other object desired to be lifted and carried.

The tongs 1717 are formed as to have elongated curved legs 19-19 and inwardly extending operating arms 2020, which cross and are pivotally interconnected at their free ends 2121 on a transverse pin or bolt 22. The size relationship and consequently the weight of the arms 2020 relative to the legs 19-19 is such that the weight of the arms acting about the pins or bolts 18-18 will bias the tongs 17--17 to their normal open position.

Closing movement of the tongs 1717 from their normal open position in effected by means of the operation of a lift rod 25. This lift rod is pivotally connected to pin or bolt 22 between the free ends of the arms at its lower end and extends vertically upwardly between the

cheek plates

13 and 14. At its upper end 27 the lift rod has a spear-head 2'8 fastened thereon as by welding or the like, said spear-head having sloped camming side surfaces 29 and a flat horizontal base 30. Below the base and extending downwardly substantially half its length, the lift rod 25 is reduced in cross sectional dimension terminating in a lower stop 33 and slidably mounted on the lift rod for free slidable movement between the base 30 of the spear-head and the lower stop 33 is a latch operator 35. This operator is relatively light and is therefore preferably annular in configuration and may be formed from a transverse section of steel pipe of suitable size. As illustrated, the operator is shown as circular, however, it may be elliptical having its major axis extending in a vertical direction.

The spear-head 28 is provided with a laterally extending tongue 36 (see FIGURE 2) which slidably extends through a slot 37 formed in cheek plate 14 so as to maintain the rod 25 in a vertical position as it moves in conjunction with movements of the tongs 17-17.

Mounted between the

cheek plates

13 and 14 is a latch carrier 40. This carrier is of hollow rectangular construction open at its top and bottom and having

side walls

41 and 42 and

end walls

43 and 44. The carrier 40 is slidably mounted between a pair of vertically extending guides 46-46 which are spaced equidistantly apart on opposite sides of the longitudinal axis of the rod 25. These guides may be short lengths of angle or channel irons and are securely fixed as by welding or the like or by means of bolts to one or both of the

cheek plates

13 and 14.

Upper stop elements 48 and lower stop elements 49 are secured as by welding to the upper and lower ends of the guides 46-46 engageable with the carrier 40 so as to limit the length of travel of the latter. These stop elements may simply be small metal blocks which are secured as by welding to the guides.

The thickness of the carrier 40 is such as to permit passage therethrough of the lift rod 25 together with the spear-head 28 and latch operator 35. The side wall 42 of the carrier is provided with a slot 50 which is vertically aligned with the slot 37 in the cheek plate 14 so as to allow slidable passage of the tongue 36 therealong.

Mounted within the carrier 40 on opposite sides of the longitudinal axis of the lift rod 25 are a pair of latches 51-51. These latches are crescent shaped and are pivotally mounted intermediate their length on pivot pins 5252 with their concave sides 53-53 facing each other. The length of these latches is such as to permit only limited pivotal movement in both directions from a substantially vertical position. The lower ends 55-55 of these latches, as viewed in FIGURES 1 and 2, extend as horns toward each other and their upper ends 57-57 are slightly flattened as at 58-58. The crescent shaped aspect of both latches provides a central receiving space 59 which is large enough to accommodate the spear-head 28 and the latch operator 35 and the latches are spaced a sufficient distance apart so that when their lower ends 55-55 are spread apart a distance equal to the width of the operator 35 their upper ends 57-57 will be spaced apart a distance less than the width of the base 30 of the spearhead 28. These latches are also restrained from free swinging movement by the provision of coil springs 60 positioned about the pins 5252 and extending under compression between the latches and side wall 41 of the carrier so as to urge the latches into frictional engagement with the side wall 42 thereof, the compressive strength of these springs being such that the latches, when arranged in a position with their lower ends 55-55 beneath the operator 35, will support the weight of the latter without moving.

The carrier 40 is provided with transverse connecting pins 61-61 extending between the side walls 4.1 and 42 thereof to which a hoisting cable 65 is secured; it being understood that the cable may extend from any cable winding drum of a hoisting machine or winch of any suitable kind that may be designed or used for lifting and loading heavy loads such as logs and the like.

The operation of the grapple may be best described with reference to FIGURES l and to 7. In FIGURE 1 the grapple is shown in an open position suspended from the hoisting cable. In this position the hoisting cable is connected directly to the frame through the mediacy of the carrier 40 which is positioned adjacent the upper ends of the guides against the upperstops 48. The weight of the arms -20 of the tongs and the weight of the lifting rod bias the tongs 17-17 to an open position.

In order to pick up a log 66 (reference FIGURE 5) the grapple 10 is lowered until the tongs 17-17 straddle a log. The hoisting cable is slacked off permitting the carrier to slide downwardly over the spearhead 28. The latter will spread the lower ends 55-55 of the latches apart and at the same time move the upper ends 57-57 together. The spearhead will then pass through the receiving space and upwardly against the upper ends 57-57 of the latches moving the latter apart and moving the lower ends 55-55 towards each other. Continued lowering of the carrier to an intermediate position as shown in FIGURE 5 will result in the lower ends 55-55 of the latches moving into camming engagement with the operator 35 which rests upon the lower stop 33 thereby spreading said lower ends and moving the upper ends 57-57 inwardly beneath and in the path of the base 30 of the spearhead. When tension is applied to the cable the carrier will move upwardly bringing the upper ends 57-57 into engagement with the base (reference solid lines in FIGURE 6) thereby directly and operatively connecting the cable and tongs so that upon further tensioning of the cable the tongs will be drawn together in gripping engagement with the log 66 which may then be hoisted and delivered to an unloading site.

In order to release the grapple from its engagement with the log, the latter is lowered to rest and the cable slackened until the carrier 40 moves down to its lower position against the lower stops 49. During this movement the operator 35 which rests upon the lower stop 33 of the lift rod 25 will have passed upwardly between the lower ends of latches and against their upper ends spreading the latter apart (reference dotted lines in FIGURE 6). When the cable is again tensioned so as to draw the carrier upwardly the latches, whose frictional engagement with the carrier is such as to permit them to support the weight of the operator, will draw the latter upwardly over the reduced portion of the shaft permitting the spearhead to move downwardly between the upper ends 57-57 of said latches into the receiving space and against the operator (see FIGURE 7) moving the latter downwardly against the lower ends 55-55 of the latches so as to spread the latter apart and permit both the operator and the spearhead to pass downwardly therethrough, thereby permitting the carrier to be slid upwardly against the upper stops 48 of the guides 46-46 thereby again connecting the frame 12 and the cable so as to permit the tongs to gravitate to their open position.

FIGURE 8 illustrates another embodiment 70 of the grapple. Grapple 70 is very similar in construction and identical in operation to grapple 10. Grapple 70 includes a frame 71 which is identical to frame 12. Grapple 70 also includes a pair of elongated tongs 72-72 which are pivotally connected as by pins 73 to the frame 71. These tongs 72-72 unlike tongs 17-17 are not weighted or formed in the manner of tongs 17-17 so as to normally gravitate to an open position.

Grapple 70 also includes a lift rod 74, the lower end 75 of which extends below the frame. The lower end 75 carries a pivot pin 76 to which a pair of connecting rods 77-77 are pivotally connected. These connecting rods diverge outwardly and downwardly and are pivotally connected as by pins to the tongs 72-72. The lift rod 74 is connected to the frame 71 and the tongs 72-72 in the same manner as its counter-part 25 of grapple is connected to the frame 12 and tongs 17-17 of the latter. The weight of the lift rod 74 is such that when it is not directly connected to the hoisting cable 78 it will, through the mediacy of the connecting rods 77-77, spread the tongs 72-72 to an open position.

The connection of the lift rod 74 to the tongs 72 through the connecting rods 77-77 permits a simple pivotal connection of the tongs and frame, however, the operation of grapple 70 is exactly the same as that of grapple 10.

It will be appreciated that both embodiments of the invention may be operated to engage, lift, lower and to be released from any load with the operation of a single hoisting cable alone. Furthermore, both embodiments are of simple and uncomplicated construction and are therefore relatively inexpensive to manufacture and very easy to maintain and operate.

FIGURES 9 to 11 illustrate yet another embodiment 90 of the invention. Grapple 90 includes a carrier 91, similar in construction to carrier 40 having spaced apart

side walls

92 and 93 and end

walls

94 and 95. This carrier may be suspended from a single load line, however, it is intended that grapple 90 be secured for operation directly between a haul-back line and a haul-out line. This carrier 91 is, therefore, provided with a pair of

links

96 and 97 connected to the

end walls

94 and 95, respectively. A haul-back cable 98 is connected to link 97 and a haul-in cable 99 connected to the link 97. It will be understood, however, that in the specification and claims following reference to the connection. of the carrier to a load line shall be deemed to mean and include its connection to the haul-back and haul-in lines as aforesaid.

The carrier 91 has, like its counter part carrier 40, a pair of elongated arcuately shaped latches 100-100 pivotally mounted on pins 102-102 extending between the

side plates

92 and 93. These latch elements, 100-100, like their counter parts 51-51 of apparatus 10, are arranged with their concave surfaces facing each other.

Slidably extending between the latches 100-100 is an elongated cylindrical supporting rod 105. This supporting rod has a cylindrical button or stop 107 at its upper end 108, the diameter of which is greater than the distance between the

side plates

92 and 93.

Through the lower end 110 of the supporting rod is passed a bolt 112 upon the shank 113 of which a pair of tongs 114-114 are pivotally mounted in crossed relationship, said tongs having lower load grasping arms 115-115 and upper operating arms 116-116.

Slidably mounted on the supporting rod is an elongated cylindrical and tubular lift rod 118. This lift rod has a conical spearhead 119 secured as by welding or the like to its upper end 120, said spearhead having a fiat base 121. To the lower end 122 of the lift rod 118 is secured, as by welding, a large diameter relatively thick disc 123, the diameter of which is greater than the 'width of the carrier 91. The lift rod 118 is connected to the operating

arms

116 and 116 of the tongs by means of short operating links 124-124, the latter being connected at lower ends 125-125 to pins 126-126, projecting from the upper ends of the operating arms 116-116 and being connected at upper ends 127-127 to pins 128-128 projecting from the disc 123.

Slidably and rotatably mounted on the lift rod 118 below the spearhead 119 thereof is an operator 133 which takes the form of a sphere. The operator 133 is free to slidably move on the lift rod between the base 121 of the spearhead and an annular stop 135 secured, as by welding, to the lift rod below the spearhead 119, the distance between the annular stop 135 and the spearhead 119 being greater than the length of the latches 102-102.

The diameter of the spearhead 119 is the same as that of the operator 133 and both bear the same size relationship to the latches -100 as their

counterparts

28 and 35 bear to the latches 51-51 of grapple 10.

The operation of grapple 90 is identical to the operation of grapple 10. With the supporting rod supported by the engagement of the carrier 91 with the stop 107, the weight of the lift rod 118 and disc 123 acting, downwardly, through the mediacy of the operating links 124-124 against the operating arms 116-116 of the tongs, will swing the load grasping arms -115 to an open position. This position is illustrated in solid lines in FIGURE 9.

Upon lowering the open tongs over a log or the like and upon slackening the cables to permit the carrier to slidably move downwardly over the lift rod 118 so that the lower ends of the latches 102-102 are spread apart by the operator 133, the upper ends of the latches will move into position beneath the base of the spearhead 119, upon tensioningof the cable to move the carrier upwardly, the lift rod 118 will be suspended from the carrier, a position as illustrated in FIGURE 10, so as to close the load gripping arms 115 about the load. The log or load may then be released by simply lowering the latter to rest, and permitting the carrier to slide downwardly sufliciently to permit the operator to engage the upper ends of the latches 102-102, as illustrated in dotted lines in FIG- URE 9, so as to permit the spearhead to pass therethrough when the carrier is again lifted upwardly to engage the stop 107 of the supporting rod.

As both the supporting rod 105 and lift rod 118 are rotatable relative to the carrier 91 the tongs may be angularly positioned to suit the load to be grasped without the necessity of angularly positioning the carrier. This feature of grapple 90 thereby eliminates the necessity of providing a single load line by means of which the grapple is to be suspended as the carrier may remain in align ment with both haul-in and haul-back lines and still permit the tongs 114-114 to be swung to any position of angularity rela'tive thereto.

What is claimed is:

1. Grapple apparatus comprising a carrier member connectable to a hoisting cable, a supporting member having a vertical slidable connection with the carrier member, upper and lower stops on the supporting member engageable by the carrier member for limiting the relative vertical movement of said members, a pair of grapple elements swingably mounted on the supporting member for movement between open and closed positions, weight means acting in the grapple elements when the supporting member is supported by the carrier member for swinging the grapple elements towards an open position, a lift rod connected to the grapple elements being adapted when connected to the carrier member to operate the grapple elements toward a closed position, latching means swingably'mounted on the carrier member engageable with the lift rod for operably connecting the latter and the carrier member and a cammed operator slidably mounted on the lift rod engageable by the latching means upon predetermined selective movement of the carrier member relative to the lift rod for swinging the latching means into and out of latching engagement with said lift rod.

2. Grapple apparatus comprising a frame, a plurality of grapple elements swingably mounted on the frame arranged to gravitate to a normal open position, a vertical lift rod operatively connected to the grapple elements for moving said elements towards a closed position, a carrier member slidably mounted on the frame for limited vertical movement between upper and lower positions through an intermediate position, said carrier member being connectable to a hoisting cable, latching means pivotally mounted on the carrier for movement into and out of latching engagement with the lift rod, a cammed operator slidably mounted on the lift rod for limited vertical movement engageable by the latching means when the carrier member is permitted to slide downwardly to its intermediate position upon slackening of the hoisting cable, to move said latching means into latching engagement with the lift rod so as to operably connect the rod and cable thereby to result in closure of the grapple elements upon subsequent tensioning of the cable and to move the latching means out of latching engagement with the rod when the carrier member is permitted to slide to its lower position thereby permitting the carrier to be moved to its upper limit of travel upon subsequent tensioning of the cable and to permit the grapple elements to gravitate to an open position.

3. Grapple apparatus as claimed in claim 2 in which the grapple elements are provided with inwardly extending operating arms eachof said arms being pivotally connected to the lift rod for operating its associated grapple element upon movement of said lift rod.

4. Grapple apparatus as claimed in claim 2 in which each grapple element is connected to the lift rod through the mediacy of an elongated connecting rod, each connecting rod being pivotally connected at one end to the lift rod and at its other end to a grapple element.

5. Grapple apparatus comprising a frame, a plurality of grapple elements swingably mounted on the frame so as to gravitate to a normal open position, a vertical lift rod operatively connected to the grapple elements for moving said elements towards a closed position, said lift rod having vertically spaced apart upper and lower stops, a cammed operator slidably mounted on the lift rod for movement between the stops, a carrier member slidably mounted on the frame for limited vertical movement between an upper and lower position through an intermediate position, said carrier member being connectable to a hoisting cable, a pair of latching elements having upper and lower ends pivotally mounted intermediate their ends on the carrier on opposite sides of the lift rod, said operator being adapted when the carrier member is permitted to slide downwardly to its intermediate position to spread the lower ends of the latching elements apart and swing the upper ends 'of the latching elements to a latching position beneath the upper stop so as to operably connect the lift rod and cable thereby to result in closure of the grapple elements when the cable is tensioned, said operator being adapted upon low- 'ering of the carrier member to its lower position to engage the 'upper end of the latching elements and move said upper ends out of the path of the upper stop and at the same time, swing the lower ends to a supporting position beneath the operator so as to permit the carrier member to be moved upwardly, upon subsequent tensioning of the cable, means to releasably maintain the latching elements in said last mentioned position until the carrier member has moved upward sufliciently to permit the upper ends of the latching-elements to clear the upper stop thereby permitting the carrier member to be moved to its upper position and thereby connect the frame and cable so as to permit the grapple elements to gravitate to their normal open position.

6; Grapple apparatus as claimed in claim in which the grapple elements are provided with inwardly extending operating arms each of said arms being pivotally connected to the lift rod for operating its associated grapple element upon movement of lift rod.

7. Grapple apparatus as claimed in claim 5 in which each grapple element is connected to the lift rod through the mediacy of an elongated connecting rod, each connecting rod being pivotally connected at one end to the lift rod and at its other end to the grapple element.

8. Grapple apparatus as claimed in claim 5 in which the upper stop is formed as an upwardly pointing spearhead having sloped side shoulders and a flat base.

9. Grapple apparatus as claimed in claim 5 in which the Operator has upper and lower camming shoulders for camming engagement with the upper and lower ends of the lacthing elements.

10. Grapple apparatus as claimed in claim 5 in which said last mentioned means comprise springs urging the latch elements into frictional engagement with the frame;

11.,. Grapple apparatus comprising a vertically elongated supporting rod having a stop at its upper end, a pair of crossed and pivotally joined tongs mounted on the lower end of the supporting rod, said tongs having upper ends extending above the point of pivotal joining, a carrier slidably mounted on, the rod, said carrier being connectable to a hoisting cable and being adaptedto be moved into engagement with the stop for supporting the supporting rod and tongs, a weighted lift rod slidably mounted on the supporting rod normally gravitating to the lower end thereof and being provided with upper and lower spaced apart stops, link means operable connecting the lift rod and the upper ends of the tongs for moving the lower ends of the latter apart under the weight of said lift rod, latching means swingably mounted on the carrier engageable with the upper stop of the lift rod for operably connecting the latter and the carrier so as to move the tongs to aclosed position when the carrier is pulled upwardly by tensioning the cable and a cammed operator slidably mounted on the lift rod for movement between the stops thereon engageable by the latching means upon selected movement of the carrier relative to the lift rod for swinging the latching means into and out of latching engagement with the upper stop on the lift rod.

12. Grapple apparatus as claimed in claim 11 wherein the supporting rod is rotatable relative to the carrier so as to permit the tongs to be angularly positioned relative to the'latter.

13. Grapple apparatus as claimed in claim 11 wherein the upper stop on the lift rod is formed as a conical spearhead having a flat radially projecting base and said latching means comprises a pair of elongated arcuately shaped elements having upper and lower ends and being pivotally mounted intermediately of their ends on the carrier with their concave sides facing each other and on opposite sides of said lift rod and supporting rod for operation by the operator into and out of the path of the spearhead.

References Cited UNITED STATES PATENTS 2,216,383 10/1940 Brandon 2941l0 3,199,161 8/1965 Hamilton 294- X GERALD M. FORLENZA, Primary Examiner GEORGE F. ABRAHAM, Assistant Examiner US. Cl. X.R. 294-409, 119