US1698053A - High-speed self-lowering lifting jack - Google Patents

Description

F'. L. GORMLEY HIGH SPEED SELF LOWERING LIFTING JACK Jan. s, 1929. 1,698,053

ig'ile'd nec; 21;'1926 's sheets-snug 1 L6' rz: S C z gaf/i E' :4//69 i0 l l lwcl'or:

I'HUZLL. Gormley,

24o Z9 ze Z5 Jan. s, 1929. J 1,698,053

F. L. GORMLEY HIGH SPEED SLF LOWERING LIFTING JACK Filed Demzl, 19.26 s sheets-sheet f3 lwenlar: .FrankL Gormley.

Patented Jan. 8, 1929. ,i

Friet.

FRANK L. GORMLEY, or BROOKLINE, MASSACHUSETTS, Assreivon To THE :BUDA CoM-`r PANY, OF HARVEY, ILLIOIS, A CORPORATION.

HIGH-,SPEED SELF-LOWERING LIFTING JACK.

Application filed December 21,1926. Serial No. 1565111.

This invention relates to lifting jacks and particularly to that class known as self-lowering jacks in which a steep pitch rotatable screw is used to raise the ram in its supporting standard.

y The object of the invention is the production of a jack of this character which is capable of supporting the heaviest loads and which may be locked to sustain the load at a given height; which may be lowered by man.- ually withdrawing a key from a vertical groove in the ram, said key automatically returning into said groove wheny released to prevent further lowering; which will provide an inner bearing for the driving shaft there-- by maintaining the screw gear and its driving gear in proper relation to each other; which is provided with means for determining the exact amount the load has been raised; which may be operated by the lifting lever in one direction only and that is in raising the ram; which may be operated in either direction by hand to raise or lower the ram; and whiclris provided with novel means for locking the lifting lever handle in the socket of the operating mechanism for imparting movement to the driving gear.

This object and other desired results are attained by the mechanism shown in the accompanying drawings.

For the purpose of illustrating the invention, one preferred form thereof is illustrated in the drawings, this form having been found to give satisfactory andreliable results, although it is to be understoodthat the various instrumentalities of which the invention consists can be variously arranged Vand organized, and the invention is not limited to the precise arrangement and organization of these instrumentalities as herein shown and described except as required by the scope of the appended claims.

Of the .drawings- Figure 1 represents a vertical section of a lifting jack embodying the principlesof the present invention. V

Figure 2 represents an elevation 'of the upper end thereof with the ram raiserin its supporting casing.

Figure Srepresents a vertical section of the automatic locking device.

Figure 4 represents a vertical section on line 4, 4, on Figs. 1 and 5.

Figure 5 represents a vertical section on r line 5, 5, on Fig. 4.

Figure 6 represents a horizontal section on line 6, 6, on Fig. 5.

Figure 7 represents ya'vertical section of the clutch mechanism on line 7 ,'7 on Fig'. 4.

Figure 8 represents a vertical section on line 8, 8, on Fig. 1. i v

Figure 9 represents a side elevation ofthe end of the handle of lifting lever. Y

, Figure 10 represents an end elevation of said handle, and

Fig. 11 represents a sectionalrview of cer'- tain details.

Similar characters indicate like parts' throughout the several figuresof the draw- This ram 14 has an enlarged head 15 adapti edto restupon the upper end of the standard 12 when in its lowestV position.

The lower end of the ram 14 has mounted therein a nut 16 threaded to the main lifting screw 17, the lower endv of which has keyed thereto a bevel gear 18 meshing with a Vbevel gear 19 formed upon the actuating shaft 20.

The shaft 2O has mounted on its outer end a device 2l for imparting rotary movement to the shaft 2O in one direction only, and that is, during the lifting operation.

Y rl"he standard 12 has a lateral extension 22, one vertical wall of which has a bearing 23 therein, in which said actuating shaft 2O is Surrounding the hub ofthe gear 18- is a bearing plate 27 having a: groove in its under face into which extend the antiffrictional members 28 resting upon vanother bearing plate 29 supported and centrally disposed within `the depression 10x in the upper face of the base 10. Y

One end of the worm shaft 26 is mounted in a bearing' inthe wall Aof the extension 22, While the opposite end is mounted in a bearing in a removable member 80, set into the, Opposite wall of said extension.

- Rollerbearings 81 and 82 are provided at Vthe opposite ends of the worm shaft 26.

VKeyedto the shaft 26 is anannular member 88V having loosely mounted thereon a worm gear 84 provided with an annular fiange-85 vhaving secured therein a ratchet 86.

The member 88 has a flange 87 at one end thereof on which is lpivotally mounted a plurality of pawls 88, normally forced outwardly by springs 89 into engagement with the teeth ofthe ratchetr86..

The wormgear v84 coacts with a vertical Y ,worm 89X4 formed upon the shaft 40.

vrthereto a disk 46 having pivotally mounted fthereon at 47 a plurality of bearing plates 48,

Y, 4adapted to move outwardly against the brake l tt arms 50 surrounding the disk 46 andbearing plates 48, said brake arms 50 being pivoted at one end at 51 to the wall 48.

' .The .opposite ends of the brake arms 50 are provided with parallel, separated exten* sions 52, between which is positioned a cam member 58 mounted upon a pin 54 extending upwardly through the cover plate 55 and hav- "ing an actuating finger 56 secured to its upper end.; l

M. Springs 58 normally retain the 'brake arms 50 in contact with the bearing plates 48 pivotally mountedupon the disk 46.

vWhen the parts are in the position indicated in the drawings there will be sufficient yfriction between the brake arms 50 and the `bearing plates 48 to retain the ram in elevated position and prevent yits lowering under the load. i VWhen it is desired to lower the load the Voperator manipulates the finger 56 causing thevcam. 58 to separate the brake arms 50, thereby reducing the frictional contact between these arms and the bearing plates 48. It is obvious that by the movement of the .flinger56 about the axis of the pin 54 any degree f of friction between the arms 50'V and plates 48 may be secured and the speed of lowyeri-ngthe ram controlled.

The'extension 22 is formedr integral with .the 'standard 12 and the partition or wall 43 is formed integral with the removable member 80, this wall being somewhat depressed and forming a chamber 59 in which the speed controlling devices 46, 48, 50, and 58, are positioned,this chamber being closed by means of the cover plate 55.

The bearing 28 is provided withv a bushing 60 and the shaft VV20 may be installed in the bearing 28 from the inner end thereof before the bushing 60 is insertedinto the outer end thereof, the said shaft being inserted into the chamber within the extension 22 through the opening in the bottom lof the standard 12v before said standard has been threaded to the base 10. Y

The bushing is then positioned within the bearing 28 andfaround the shaft 20 and then the casing 21 of the actuating device is installed on the outer end of said shaft. Y

The wormgear 24 and the worm 25 rotate .l i

both when the ram is being raised andV also when it is being lowered.

Vlhen the load is being lifted the worm 89x and worm gear 84 arey prevented Vfrom anism 46, 48 and 50.

The ram 14 has a vertical groove 60 eX-.

tending its entirelength, this groove having flat parallel sides, and in theV upper end of the standard 12 lis a slot 61 of the same width as said groove 60;

` being rotated by means of the braking mechlll) On the opposite sides of said slot, ears 62 extend outwardly from said standard 12the vspace between the upper portions of lsaid ears 62 being covered by a plate'68 held in position i.

by the pins 64, 65 extending through said ears.

rthe upper pin 64 has pivotally mounted thereon the depending key 66 of the same width as the groove 60 and the lower end of said key 66 is provided with a trigger 67,'v extending outwardly beneath said closing plate and by which the key 66 may be removed from said groove 60 when it is desired to lower the ram 14.

A spring 68 is secured at one end to the closing plate 68 with its other end disposed in a recess in the key 66 and this spring retains .the key 66 in the groove 60 under normal conditions.

If the key 66 is removed from the groove 60 :to permit the lowering of the ram, the ram will loweras long as the operator holds the key in its outer position, but as soon as the key is Vreleased the spring 68 will force the key 66 inwardly and when the groove 60 comes opposite said key in the rotation of the `ram 14 said key will enterv the groove 60 and prevent any further rotation and lowering of the ram 14.

This simple device is of considerable importance for it is obvious that the operator must hold the key in its outermost position when the ram 4is to be lowered and no further lowering will occur after he releases said key and permits. the spring 68 to function.

At one side of the vgroove 60 is a scale 69 which indicates the height the load has been raised which is ofv great advantage, particularly where a load is being raised on a plurality of'jacks' operating at the same time and it isnecessary to keep the load level during the raising operation. The nut 16 is made at its upper end of smaller diameter than at its lower end thereby formingV an-annular space 70 for lubricant and from the bottom-of this space 70 extend inclined passages 71 to the'top of the nut and to a point near the bottom of the nut, all as shown in Fig. 1-. f Y

One of the screws 72 for securing the enlarged head to the top of the ram 14 is removable to permit the insertion of a heavy Y oil into the chamber 73 within the ram 141 and this oil will flow through the upper inclined passages 71 to the annular space 70 from whichjitwill flow through the lower inclined passages onto the threads of the screw 17. v

By this means'the threads of the nut 16 will be kept thoroughly lubricated at all times, a new supply of oil being inserted into the chamber 7 3 each day. Y The inner end of the driving shaft hasl a reduced end 74 extending into a ball bearing 'Z5-mounted in a recess in one faceof a member 76 depending from a pin 77 extending transversely of the extension 22.

The pin 76 is prevented-from rotating'in its bearing by a small key 78 but permits a swinging movement of the .depending member 7 6 about the axis of said pin. This construction is of great advantage as heretofore the weight applied to the end of the lifting lever when raising a load had a tendency to separate the two bevel gears 18, 19. This separation of the gears caused a binding effect between the teeth of the gears and also .on the bearing for the driving shaft. The result was that the teeth could not get an even bearing on the pitch circle as all the strain was forced `to the heel of the tooth. Consequently, the gears worked continually out of line and caused a binding which greatly increased the friction when working under a load. Y

By providing a ball bearing for the inner end of the driving shaft the gears are always iny proper position relatively to eachother and there is absolutely no bindingVv or cramping effect as the teeth always get an even bearing on the pitch circle.

This reduces the friction and greatly increases the efficiency of the entire jack.

By removing the closure 79in the extensic-n 22 the worm 28 may be readily lubricated and by removing the closure 80 oil may be admitted to the interior of the bushing forming the bearing 23 for the driving shaft 20.

The driving shaft 20 extends beyond the outer end of the bearing 23V and on a flat sided portion 81 thereof is mounted the ratchet 82 while a. reduced portion 83 thereof extends through a bearing in one Wall of the casing 21 and has a transverse pin 84 therein toretainv said casing 21 in position.

, The opposite wall of the casing 21 has an opening therein large enough to admit the ratchet 82 into the interior chamber of the casing.

This opening is closed, when the casing 2,1

is'positioned on the shaft 20: by a collar 85 surrounding said shaft.

Abovel the Vratchet 82 the casing 2l has i mounted .therein an oscillating pin 86 with a head87 at one end and a winged turning member 88 secured'to its opposite end.

SOv

Keyed to the pin 86 within the casing chami posed a ball backed by a spring 94 tending l to force the ball 95 downwardly against one wall of the pawl v89.

The pawl 89 has two walls perpendicular" to each other and in one wall is a V-shapedy groove 96`into which a portion of the ball 95 is adapted to extend and lock the pawl in adjusted position with one set of teeth 90 in engagement-with the teeth of the ratchet.

This groove 96 is slightly at one side of the plane extending through the axes of the shaft 2O and the opening 92, as of the drawings.

Asa consequence the ball 95 bears onv only 'one wall of the groove 96 and holds the pawl teeth and ratchet teeth in engagement during the lifting operation. f

Extending from a side wall of the casing 21 is an inclined extension 97 having a socket 98 therein to receive the tapered portion 99 of the handle 100. i

This tapered portion 99 ofthe handle 100 indicated in Fig- 8 has extending inwardly from its end a groove 101 with a flaring mouththe inner end of said groove being curved around the periphery of the tapered portion 99 as indicated at 102. l c

Threadedto the extension 97 is a member 103 provided with ball shaped end 104 which extends into the socket 98 and is adapted to enter the groove 101 when the taperedportion of the handle is inserted into the socket.

By constructing this actuating mechanism in the manner-shown and described, the moving parts, namely the pawl and ratchet, are

enclosed within the casing l21 and kept free from dirt.V l

The lifting pawl 89 has a two point contact, one forraising the ram by means of the handle I100 and the other. for either raising or lowering the ram by manipulating the casing 21 without thehandle or lever 100. c f

When this casing is to be actuated by hand the vbrake levers 50 must be separated and the operatormoves the casing 21 about the axis ofthe shaft by means of the rside projec* tion 105 provided for this purpose.-

This operation by hand can only be accomplished when 4there is no load upon the ram. As soon as the operator releases the lifting member 21 the lifting pawl will innnediately and automatically return to its neutral posi- `tiOn'. .Y

` operator to make a lmistake in lifting a load for there is only one position in which the lifting pawl will operate and that is in the lifting position.

When there is no load on the yram 14 it may be lowered more quickly than-by the actuay tion of the lever socket by hand.

- and provision This is accomplished by withdrawing the kkey 66 from the groove 60 and turning the ram by hand. Y

It is often. desired to leave the load on the ram in raised position for an indelinite period is therefore made to meet this condition. l E

This `is accomplished by means of the screw V10G threaded in the member 30 and having a winged head 107 on the outer end anda head 108 on its inner end. j

This screw Vradiates from the worm 39 c meshingcwithworm gear 34 and when the head 108 is moved into a position against the threads of the worm 39X, this worm is locked from rotating and there can be no lowering until the head is again disengaged from the worm.

It is obvious thatwhen thus locked the operator does not depend upon springs vto hold the load. c This is ofgreat advantage as springs are not always safe, especially when workmen are under the load. This safety feature is of considerable importance. v

The standard 12 is threaded tothe upwardly extending projection 11 of the base 10 and is prevented from turning thereon when assembled bythe screw 12X extending through the lower endof the standard into .said projection 11, as indicated in Fig. 1.

Thelower end of the ram 14 has at its lower end a shoulder 14X adapted to coact with a shoulder13X atv the upper end of the standard to limit the upward movement of the ram14.

The screw 17 has a left hand thread and acc lifting cf thc iccd is ccccmpiichcd by bearing down on the lever 100.

Thepawl 89 andratchet 82 are wholly en- In addition tothe notch 96, the pawl 89 has another notch 96? therein midway of the two lsets of teeth 90 and whenthe pawlV 89 is moved into a vposition with the Vnotch 96x alined with .the opening 92, the ball will enter thenotchfQtX and retain said pawl in a Vneutrall position with neither seti of teeth 90 in engagement with Vthe ratchet 82.

Jill-ien inthis positiony the ram cannot be raised orlowered by the'device 21.

/Vhen it isv desired to lower by hand with no load upon the ram the turning device 88 is turned clockwise to bring the right hand set of teeth 90 (see Fig. 8) into engagement with the ratchet teeth and then by holding the turning member 88 in this position the device 21 may be'moved about the axis of the shaft 20 in either direction to'fraise or lower the 1 ram.

As soon as the operator releases the turning member 88 the pawl 89 will return to its neutral position automatically. l

The head 108 on the innerend of the screw 106 of soft metal and is adapted to be jammed against the thread of the worm 39c so that it cannot be rotated. c

rrac brcicc dick i9 cctcccc in Jchc dirccdc'c ci 'i the arrow'on Fig. Gand inthe rotation of said disk the bearingplates 48 will be moved outwardly about their pivots by centrifugal force.

When thus moved outwardly the plates 48 will be brought intovfrictional engagement with the' arms-50 and the speedk of lowering may be regulated. f

The bearing plates 48 have elongated slots 110 in their outer ends through each of which extends a pin 111 projecting upwardly from the disk 49.

These pins 111 limit the outward movement of the bearing plates 110, thereby making it ossible to separate the arms 50 to such an extent that they `will be wholly separated from said plates 48 and removeall frictional v Y.

contact. Y y

When the contact is thus removed, the ram may be lowered more rapidly under a light Having` thus described. my invention, l claim:

1. In a lifting jack provided with a steep 12o y* Vload than would be possible if the plates 48 y were in frietional contact with the arms 50.

' elongated vertical opening therein with flat ing a reduced cylindrical inner end;inter parallel sides and projecting ears; a vertically movable ram in said casing having aperipheral slot with flat parallel sides extending lengthwisethereof; a closing plate interposed between said ears; a. locking lever pivoted at its upper end to said ears and provided at its lower` end with an actuating finger extending outwardly beneath said closing plate; and a. spring between saidclosing plate and locking lever, said spring being secured at one end to said closing plate and the other end disposed in a depression in the lock= ing lever and adaptedtoforce said lever in.n wardly` c 3. In a lifting jack provided with a steep pitch rotatable screw, a supporting casing tlierefo-r, and a vertically movable ram; a nut liXedly secured in the lower end of the ram and coacting with said screw, said nut having passages extending to the to-p thereof through which lubricant Vmay pass to the threads of said screw. i

4. In a lifting jack provided with a steep pitch rotatable screw, a supporting casing therefor, anda vertically movable ram; a nut fiXedly secured in the lower end of the ram and coacting with said screw, said nut having its upper end reduced in diameter providing an annular space for lubricant and having inclined passages extending to the top thereof and to a 4point near its bottom whereby lubricant may pass to the screw threads.

5. In a lifting jack provided with a steep pitch rotatable screw, a casing therefor, and a vertically movable rim; a driving shaft rotatable inabearing in said casing and havmeshing gears on the lower endof the screw and inner end of said shaft; and a bearing for said inner end disposed above the screw gear and out of the path of said ram. Y 6. In a lifting jack provide-d with a steep pitch rotatable screw, a casingv therefor, and a vertically movable ram; a driving shaft rotatable in a bearing in said casing andhaving a reduced cylindrical inner end; inter- Y meshing gears on the lower end of the screw and inner end of said shaft; a vertical member within said casing Vdisposed, above` thev screw gear and out of the path of said ram; and a bearing removably mounted in said member for said inner end. i

v 7. lInAV a lifting jackl provided with a steep pitch rotatable screw, a casing therefor, and a 1 vertically movable rain; a. driving shaft r0- tatable in a bearing in said casing and having a reduced cylindrical inner end ;A a horizontal .pin supported by said casing; a member de,-A pending therefrom and a bearing forsaid in-v ner end formed in the lower end of said member. i

8. In a lifting jack provided with a steep pitch rotatable screw; a supporting casing therefor, anda vertically movable ram; a bevel gear secured to the lower endof said screw; a driving shaft having a bevel gear meshing with the screwv gear; a worm gear on and rotatable with said shaft; -a wormy above said worin gear and meshing therewith; and automatic brake mechanism ksurrounding one end of, said worm and coacting therewith for retaiding the lowering of said ram,

9. In a lifting jack provided with a steep pitch rotatable screw, a supporting casing therefor, and a vertically movable ram; a bevel gear secured to the lower end ofsaid screw; adriving shaft having a bevel gear i meshingwith the screw gear; a-worm gear Y on and rotatable with said shaft; a worm meshing with said `worin gear and meshing therewith; a removable member secured to said casing; and brake mechanism for regu lating the lowering of the ram mounted on-v and movable with said removable member; said brake mechanism being normally con-` nected to one end of said worm, butdetach-V able therefrom.

, 10. In a lifting jack provided with. a steepl pitch rotatable, screw, a supporting casing therefor, and a vertically movable ram; a bevel gear secured to thelower endofsaid screw; a drivingA shaft having'a bevel gear meshing with the screw gear; a lworm gear on and rotatable with said shaft; a worin meshing wit-h said worm gear; a removable member Vsecured to said casing; and' brake mechanism ymountedV on said removable member vand normally coacting with andlhaving a bearing for one end offsaid worm, said brake mechanism beingv adapted to c regulate the lowering of the ram.

11. In a lifting jack provided with alsteep f pitch rotatable "screw, a supportingv casing therefor, and avertically movable ram; a

bevel gear secured to the lower end .of said screw; a driving shaft having a bevel gear meshing with the screw gear; a` worm gear on and rotatable with said shaft; a WOrmmeSh-v ing with said wormgear; a removable meinber secured to said casing c in two sections bolted together; mounted on the lower sectionV of said removworm, said brake mechanism being covered by and brake mechanism able member and'normally coactingwith said thel upper section and adapted to regulateV Y the lowering of the ram. A c

pitch rotatable screw, a supporting-,casing therefor,and a vertically movable ram;-:;a=

V: l2.In alifting jack providedwith a-steepy l' lit,

y b'evel ygear secured yto 'the lower end of said screwg. a driving shaft having a bevelgear .meshing with the screwgear; a worm gear on and rotatable with said shaft; afworm Ylo cam shaft. y Y Y '13. In a lifting jack provided with-a steep meshing with said worin gear; a reino-vable member secured to said casing in two sections bolted together; brake mechanism mounted on vsaid removable member and normally coacting withsaid wrm,'said brake mechanism being adapted to vregulate the lowering of the ram and including a cam shaft extending through the' upper section; Va cam actuating lever above said upper section secured to said on and rotatable wit-hsaid shaft; a wormV meshing with said worin gearga removable- Vmember secured to-said casing in two sections lbolted together g-bralre mechanism mounted on'the lower sect-ion of said removable member vand normally coacting with one end of said worm, said brake mechanism being adapted to regulate the loweringof the ram and including a cam shaft extending through the upper section; a cam actuating lever Vabovefsa'id upper section securedV toV said shaft, a cam on the lower end of said cam shaft; brake arms on the opposite sides of said cam; and expansionsprings forl retaining said'arms in contact with said cam.

14. `In a lifting ack provided with a steep pitch rotatable sere/w, a supporting casing therefor, and lavertically -movable ram; a bevel gear secured to the lower end of said screw; a driving shaft having a bevel gear meshing with .the screw gear; a worm. gearV on and rotatable withsaid shaft; a worm'meshingtherewith; brake mechanism. coacting with said worm for retarding the lowering of said ram and including a second worm; and means coacting with the thread of said second worm and positively preventing the rotation i thereof.v

Ysaid worm and includingasecondworm; and

a member adjustable endwise having a head at its inner end adapted `to -coact with the thread. Of Saidv Second Worn-1 Prevent ro;

16. Ina lifting jacl provided with a steep` .pitch rotatable screw, a supporting casing therefor', and a vertically-movable ram; aV

bevel gear secured :to the'lower end of said screw; a driving shaft having a bevel gear meshing with the screwgear; a worm gear on and rotatable with said shaftga worm meshing therewith; a brake mechanism coacting with said worm, said brake mechanism being adapted to regulate the lowering of the pitch rotatable screw, a supporting casing therefor, and a vertically movable ram; a bevel gear secured to the-lower endof said screw; a driving shaft 'having va bevel gear meshing with the screw gear; 'a brake mechanism including a plurality ofV movable members; and a safetyde'vice for positively locking the movable members 'from' rotation adapted to be moved into engagement with one of said movable members.

`18. In a lifting jack provided with a steep pitchv rotatable screw, a Lcasing therefor;-V and a vertically movable ram; a driving shaft rotatable in a bearing in said casing and having a reduced cylindrical inner end', and a member provided with a bearingfor saidin- Aner end and adapted to be removably positioned within ysaid casing. Y

19.` In a lifting jack providedwith a steep pitch rotatable screw, a casing therefor ;V and a vertically movable ram; adriving shaft rotatable in a bearing in said casing and having a reduced cylindrical inner end;` a swing member within said casing Yand ananti-friction bearing for said inner end mounted" in said member.

20. A lifting jack comprising a casing; a rotatable lifting screw and aV driving shaft mounted in said casing with their axes disposed at an angle to each other and in a common vertical plane, a driving connect-ion'fbetween said shaft and screw; a vertically movable ram on said screw; and afbearing above the screw driving connection and in which the inner end of said shaft is journaled, said bearing being outside the boundary of said rain. 2l. In a lifting ack, the combination ofl a lifting screw; av driving shafttherefor,z an operating lever for said shaft; and means including a casing mounted on lsaid driving shaft for automatically establishingan opeiative connection b'etween's'aid 'lever and said shaft uponv movement of thelever in one direction only, said meansv also' includingV a movable device adapted to be retained by hand in adjusted position wherebyth'e casing iay be temporarily connectedto the shaft upon movement of the casing in the opposite direction;

i Signed 'by me at 746 Oldl South Bldg., Boston, Mass., thisQ/'r'thday of November,

1926, Y f n "FRANK L. GTORMLEY.` x

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