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US1680514A - Lifting jack - Google Patents

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US1680514A
US1680514A US86418A US8641826A US1680514A US 1680514 A US1680514 A US 1680514A US 86418 A US86418 A US 86418A US 8641826 A US8641826 A US 8641826A US 1680514 A US1680514 A US 1680514A
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Prior art keywords
key
ram
slot
casing
screw
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Expired - Lifetime
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US86418A
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Frank L Gormley
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BUDA CO
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BUDA CO
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Priority to US86418A priority Critical patent/US1680514A/en
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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B66HOISTING; LIFTING; HAULING
    • B66FHOISTING, LIFTING, HAULING OR PUSHING, NOT OTHERWISE PROVIDED FOR, e.g. DEVICES WHICH APPLY A LIFTING OR PUSHING FORCE DIRECTLY TO THE SURFACE OF A LOAD
    • B66F3/00Devices, e.g. jacks, adapted for uninterrupted lifting of loads
    • B66F3/08Devices, e.g. jacks, adapted for uninterrupted lifting of loads screw operated

Definitions

  • This invention relates to lifting jacks and particularly to locking means preventing the rotation of the ram under normal conditions, said locking means being removable from the ram when it is desired torapidly raise or lower the ram.
  • Figure 1 represents an elevation of a lifting jack embodying the principles of the present invention, the upper part of which is shown in section.
  • Figure 2 represents a horizontal section of same on line 2, 2 on Fig. 1, and
  • Figure 3 represents a side elevation of the upper end of said jack.
  • the drawings 10 is the base of a lifting jack having a casing 11 extending upwardly therefrom.
  • a ram 12 adapted to he moved vertically in the bearing 13 by means of a rotatable screw 14 having a steep pitch as shown.
  • the lower end of the ram 12 is provided with the usual nut in engagement with the screw 14 and said screw is rotated in the usual manner through gearing by an actuat ing lever applied to the shaft 15.
  • the ram 12 for its entire length is provided with a vertical slot 10 in its periphery into which normally projects a key 17 which when disposed in saidslot 16 prevents the rotation of said ram :12.
  • the ram 12 has a top plate 18 normally resting on the upper end of the casing 11, thls plate having radial sockets 19 for the reception of any suitable tool by which the ram 12 may be moved about its axis when the key 17 is removed from the slot 16.
  • the ram 12 may be rotated by hand when the key 17 is removed from slot 16. i
  • the casing 11 has an opening 20 near its upper end in which said key 17 is movable toward and from the axis of the ram 12, portions of the side walls of said key being always in contact with the side walls of said opening.
  • the casing'll is provided" with parallel vertical flanges 21 through which extend pins 22, 23, which pins also extend through ears formed upon a cover plate 24.
  • a lever 25 Pivotally mounted on the pin 22 is a lever 25 having an opening 26 therein through which extends the headed bolt 27, the inner end of which is threaded to said key 17.
  • the lower end 30 of the lever 25 projects below the lower edge of. the cover plate 24 and is removed sufficiently from the casing 11 to permit the operator to grasp said lower end 30 and move the lever 25 about its pivot sufficiently to entirely disengage the key 17 from the slot 16 in ram 12.
  • the key 17 is alwaysin the slot 16 when the load is being lifted, but when the load hasbeen raised it is sometimes desirable to' lower the ram quickly without using the usual actuating lever as is the commonprac tice with lifting jacks of this type To accomplish this the operator places his finger behind the end 30 and moves the lever 25 outwardly about its pivot, compressing the spring 29 and removing the key 17 from slot 16. j I
  • the locking device is all enclosed except the end 30 which is exposed in such a manner as to make it readily accessible to the operator when he desires to remove the key 17 from slot 16.
  • Such a locking mechanism is a distinct improvement over jacks provided with fixed keys in the shell or casing 11 or jacks which have no provision for preventing the ram from turning during thelifting of the load.
  • a self-lowering lifting jack provided with a steep pitch screw, a supporting casing having an elongated vertical opening therein with parallel flat sides, and a vertically movable ram in said casing freely movable downwardly on said screw when at rest and having a peripheral slot with flat parallel walls extending lengthwise thereof said slot having the same width as said opening;
  • a flat-sided key freely movable in said casing opening in a radial path and in contact with the side walls thereof; an actuating lever pivoted at its upper end to said casing and depending from its pivot adapted to move said key outwardly from said slot; and means in the same plane with the key for automatically returningsaid key into said slot when said lever is released.
  • a self-lowering lifting jack provided with a steep pitch screw, a supporting casing having an elongated vertical opening therein with parallel flat sides, and a vertically movable ram in said casing freely movable downwardly on said screw when at restand having a peripheral slot extend ng lengthwise thereof with parallel flat side walls spaced apart the same distance as the sides of said opening; a flatsided key freely movable radially in said casing opening in contact with the side walls thereof; manually actuated means pivoted to said casing near the top of said opening for moving said key from said slot, said moving means depending from its pivot; and means for automatically returnin sait key into said slot when said moving means is released.
  • a self-lowering lifting jack provided with a steep pitch screw, a supporting casing having an elongated vertical opening therein with parallel flat sides, and a vertically movable ram in said casing freely movable downwardly on said screw when at rest and having a peripheral slot extending lengthwise thereof; a fiat-sided key freely movable in said casing opening in contact with the flat sides thereof; manually actuated means on said casing for moving said key radially from said slot; and resilient means and eoacting directly with the key independent of said moving means for auto matically returning said key into said slot as soon as said moving means is released.
  • a self-lowering lifting jack provided with a steep pitch screw, a supporting casing having an elongated vertical opening therein with parallel flat sides, and a vertically movable ram in said casing freely movable downwardly on said screw when at rest and having a flat sided peripheral slot extending lengthwise thereof; a flat-sided key slidable in said casing opening in contact with the sides thereof and having a lateral shouldered projection radial to the axis of said ram; an actuating lever pivoted to said casing at the upper end of said opening and adapted to engage said projection to remove the key from said slot; and a spring for forcing said key intosaid slot when the lever is released;
  • a self-lowering lifting jack provided with a steep pitch screw, a supporting casing, and a vertically movable ram therein having a peripheral slot extending lengthwise thereof, said ram being freely movable downwardly on said screw when the screw is at rest; a key slidable endwise in an opening in said casing; a leverpivoted to said casing and having a. hole therethrough; a head ed bolt extending through said hole into said key and means for ap lyin sprin pressure to the outer end of said bolt.
  • a self-lowering lifting jack provided with a steep pitch screw, a supporting casing having an elongated vertical opening therein with parallel flat sides, and a vertically movable ram in said casing having a peripheral slot extending lengthwise thereof, said ram being freely movable downwardly on said screw when the screw is at rest; a flat sided key slidable radially in an opening in said casing in contact with the side walls thereof and extending normally into said slot; manual means disconnected from said key but coacting with a central part thereof for removing it from said slot; and automatic means for returning the key to its normal position projecting into said slot as soon as said moving means has been released.
  • a selflowering lifting jack provided with a steep pitch screw, a supporting easing having an elongated vertical opening therein with fiat parallel sides, and a vertically movable ram in said casing having a peripheral slot extending lengthwise thereof, said ram being freely movable downwardly on said screw when the screw is at rest; a fiat sided key slidable in said opening between the side walls thereof and extending normally into said slot, said key having midway of its length a headed projection; means coacting with one side of the head of said projection for removing said key from said slot; and a spring coacting with the opposite side of the head for forcing inwardly said key and moving means.
  • a self-lowering lifting jack provided with a steep pitch screw, a supporting casing having an elongated vertical opening therein with parallel fiat sides and a vertically movable ram in said casing freely movable downwardly on said screw when at rest and having a flat sided peripheral slot extending lengthwise thereof; a fiat-sided key freely movable in said opening in contact with the side walls thereof; a stud centrally disposed in said key; a spring coacting with said stud to project a portion of said key into said slot; and an actuating lever movable about a pivot at the top of said opening and depending therefrom and having a hole therein through which said stud extends, said stud having ahead bearing on the outer face of said lever.
  • a self-lowering lifting jack provided with a steep pitch screw, a supporting casing having an elongated vertical opening therein with parallel flat sides and a vertically movable ram in said casing freely movable downwardly on said screw when at rest and having a flat sided peripheral slot extending lengthwise thereof; a fiat-sided key freely movable in said opening in contact with the side walls thereof; a stud centrally disposed in said key and provided with ahead on its outer end; an actuating lever pivoted at its upper end with its central portion interposed between said key and head; and resilient means for normally forcing a portion of the key into said slot.
  • a self-lowering lifting jack provided with a steep pitch screw, a supporting casing having an elongated vertical opening therein with parallel flat sides and a vertically movable ram in said casing freely movable downwardly on said screw when at rest and having a peripheral 7 slot extending lengthwise thereof; a flat-sided key freely movable in said opening between parallel ears projecting from said Casing; a closing plate secured to said ears and closing the upper and outer ends of the space between said ears; a stud centrally disposed in said key and provided with a head on its outer end; an actuating lever pivoted at its upper end to said ears and depending from said pivot with portions thereof between said key and head and its lower end extending slightly below said closing plate; and resilient means between said head and plate for forcing a portion of said key into said slot when said lever is released.
  • a self-lowering lifting jack provided with a steep pitch screw, a supporting casing and a vertically movable ram in said casing freely movable lengthwise of the screw when the screw is at rest, said ram having a flat-sided vertical slot extending lengthwise of its periphery; a flat sided key movable in a straight path in contact with the side walls of an opening in said casing and adapted to partially enter said slot to prevent further rotation of said ram; a manually actuated member for withdrawing said key from said slot; and a spring in the same plane with the key for forcing said key inwardly when said member is released.
  • a self-lowering lifting jack provided with a steep pitch screw, a supporting casing and a vertically movable ram in said casing freely movable lengthwise of the screw when the screw is at rest, said ram having a flat-sided vertical slot extending lengthwise of its periphery; a flat-sided key positioned in an opening in said casing and adapted to partially enter said slot to prevent further rotation of said ram; said key being movable radially to the axis of said screw and in contact with the opposite vertical walls of said opening; a depending manu ally actuated member for withdrawing said key from said slot, said member being pivoted to said casing near the top of the key; and a spring for forcing said key inwardly against the periphery of the ram when said member is released and impart further inward movement thereto when said slot and key are int-he same plane.

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  • Life Sciences & Earth Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Geology (AREA)
  • Mechanical Engineering (AREA)
  • Structural Engineering (AREA)
  • Forms Removed On Construction Sites Or Auxiliary Members Thereof (AREA)

Description

F. L. G ORMLEY LIFTING JACK ,ile Fame, 1926 15 .1?
Aug. 14, 1928.
- Irwentor:
E'ank LGormZcy,
Patented Aug. 14, 1928.
UNITED STATES 1,680,514 PATENT OFFICE.
FRANK L. GORMLEY, OF BROOKLINE, MASSA(LI*IUS]E}'1"IS ASSIGNOR TO THE BUDA COMPANY, HARVEY, ILLINOIS, A CORPORATION OF ILLINOIS.
LIFTING JACK.
Application filed February This invention relates to lifting jacks and particularly to locking means preventing the rotation of the ram under normal conditions, said locking means being removable from the ram when it is desired torapidly raise or lower the ram. 1
The object of the present invention is the provision of simple means which will obtain this desired result, which result is accomplished by the mechanism illustrated 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 and reliable results, although it is to be understood that the various instrumentalities of which the invention consists can be variously arranged and organized, and the invention is not lim ited to the precise arrangement and organization of these inst-rumentalities as herein shown and described except as required by thescope of the appended claims.
Of the drawings:
Figure 1 represents an elevation of a lifting jack embodying the principles of the present invention, the upper part of which is shown in section. I
Figure 2 represents a horizontal section of same on line 2, 2 on Fig. 1, and
Figure 3 represents a side elevation of the upper end of said jack.
Similar characters indicate like parts throughout the several figures of the drawin s.
Tn the drawings 10 is the base of a lifting jack having a casing 11 extending upwardly therefrom.
Within the casing 11 is a ram 12 adapted to he moved vertically in the bearing 13 by means of a rotatable screw 14 having a steep pitch as shown.
The lower end of the ram 12 is provided with the usual nut in engagement with the screw 14 and said screw is rotated in the usual manner through gearing by an actuat ing lever applied to the shaft 15.
As this mechanism forms no part of the resent invention it is deemed unnecessary to illustrate the same. 7
The ram 12 for its entire length is provided with a vertical slot 10 in its periphery into which normally projects a key 17 which when disposed in saidslot 16 prevents the rotation of said ram :12.
e, 1926. Serial No. 86,418.
The ram 12 has a top plate 18 normally resting on the upper end of the casing 11, thls plate having radial sockets 19 for the reception of any suitable tool by which the ram 12 may be moved about its axis when the key 17 is removed from the slot 16.
Ordinarily, however, the ram 12 may be rotated by hand when the key 17 is removed from slot 16. i
The casing 11 has an opening 20 near its upper end in which said key 17 is movable toward and from the axis of the ram 12, portions of the side walls of said key being always in contact with the side walls of said opening.
On opposite sides of said opening 20 the casing'll is provided" with parallel vertical flanges 21 through which extend pins 22, 23, which pins also extend through ears formed upon a cover plate 24.
Pivotally mounted on the pin 22 is a lever 25 having an opening 26 therein through which extends the headed bolt 27, the inner end of which is threaded to said key 17.
The head 28 of said bolt is forced against the outer face of lever 25 by the spring 29 interposed between the head 28 and the cover plate 24. 1 I
The lower end 30 of the lever 25 projects below the lower edge of. the cover plate 24 and is removed sufficiently from the casing 11 to permit the operator to grasp said lower end 30 and move the lever 25 about its pivot sufficiently to entirely disengage the key 17 from the slot 16 in ram 12.
When the jack is being operated in the usual manner a portion of the key 17 is forced into the slot 16 by means of the spring 29 and any rotation ofthe screw 14 will impart .reciprocatory movement to .1 the ram 12. v
The key 17 is alwaysin the slot 16 when the load is being lifted, but when the load hasbeen raised it is sometimes desirable to' lower the ram quickly without using the usual actuating lever as is the commonprac tice with lifting jacks of this type To accomplish this the operator places his finger behind the end 30 and moves the lever 25 outwardly about its pivot, compressing the spring 29 and removing the key 17 from slot 16. j I
- The operator with one. hand retains the lever 25 in this out-Ward position thereby permitti g he ram 12 to rotate freely as soon as with the other hand he has given a slight turn to the ram.
As the thread of the screw 14 and its coaeting nut is ofcoarse pitch the ram will descend very quickly.
When it is desired to stop the ram at any point the operator simply releases the lever 25 and the expansion of spring 2!) will force the key 1.7 into the slot 16 as soon as said slot in the rotation of the ram comes into register with said key.
This having been accomplished further rotation of theram12 is prevented.
Sometimes after raising the ram by the usual means it may be necessary to run out the ram a eertaindistance to reach the load to be lifted. 'In such acase the key 17 is removed from slot 16 in the manner just described and the ram is turned in a reverse direction, i. e., in a direction opposite to that in which it turns in lowering, anddue to the coarse pitch of the thread of screw 14 the ram 12 may be elevated very rapidly as compared with the movement thereof when operating with the ordinary lever and the gears actuated thereby.
' The locking device is all enclosed except the end 30 which is exposed in such a manner as to make it readily accessible to the operator when he desires to remove the key 17 from slot 16.
It will be noted that the return of the key into the slot 16 is automatic and requires no attention on the part ofthe operator.
Such a locking mechanism is a distinct improvement over jacks provided with fixed keys in the shell or casing 11 or jacks which have no provision for preventing the ram from turning during thelifting of the load.
From the foregoing explanation it is believed that the operation and many advantages of the invention will be fully understood. j
Having thus described my invention, I claim:
1. In a self-lowering lifting jack provided with a steep pitch screw, a supporting casing having an elongated vertical opening therein with parallel flat sides, and a vertically movable ram in said casing freely movable downwardly on said screw when at rest and having a peripheral slot with flat parallel walls extending lengthwise thereof said slot having the same width as said opening;
a flat-sided key freely movable in said casing opening in a radial path and in contact with the side walls thereof; an actuating lever pivoted at its upper end to said casing and depending from its pivot adapted to move said key outwardly from said slot; and means in the same plane with the key for automatically returningsaid key into said slot when said lever is released.
2. In a self-lowering lifting jack provided with a steep pitch screw, a supporting casing having an elongated vertical opening therein with parallel flat sides, and a vertically movable ram in said casing freely movable downwardly on said screw when at restand having a peripheral slot extend ng lengthwise thereof with parallel flat side walls spaced apart the same distance as the sides of said opening; a flatsided key freely movable radially in said casing opening in contact with the side walls thereof; manually actuated means pivoted to said casing near the top of said opening for moving said key from said slot, said moving means depending from its pivot; and means for automatically returnin sait key into said slot when said moving means is released.
3. In a self-lowering lifting jack provided with a steep pitch screw, a supporting casing having an elongated vertical opening therein with parallel flat sides, and a vertically movable ram in said casing freely movable downwardly on said screw when at rest and having a peripheral slot extending lengthwise thereof; a fiat-sided key freely movable in said casing opening in contact with the flat sides thereof; manually actuated means on said casing for moving said key radially from said slot; and resilient means and eoacting directly with the key independent of said moving means for auto matically returning said key into said slot as soon as said moving means is released.
4. In a self-lowering lifting jack provided with a steep pitch screw, a supporting casing having an elongated vertical opening therein with parallel flat sides, and a vertically movable ram in said casing freely movable downwardly on said screw when at rest and having a flat sided peripheral slot extending lengthwise thereof; a flat-sided key slidable in said casing opening in contact with the sides thereof and having a lateral shouldered projection radial to the axis of said ram; an actuating lever pivoted to said casing at the upper end of said opening and adapted to engage said projection to remove the key from said slot; and a spring for forcing said key intosaid slot when the lever is released;
5. In a self-lowering lifting jack provided with a steep pitch screw, a supporting casing, and a vertically movable ram therein having a peripheral slot extending lengthwise thereof, said ram being freely movable downwardly on said screw when the screw is at rest; a key slidable endwise in an opening in said casing; a leverpivoted to said casing and having a. hole therethrough; a head ed bolt extending through said hole into said key and means for ap lyin sprin pressure to the outer end of said bolt. O p
6. In a self-lowering lifting jackprovided with a steep pitch screw, a supporting casing having an elongated vertical opening therein with parallel flat sides, and a vertically movable ram in said casing having a peripheral slot extending lengthwise thereof, said ram being freely movable downwardly on said screw when the screw is at rest; a flat sided key slidable radially in an opening in said casing in contact with the side walls thereof and extending normally into said slot; manual means disconnected from said key but coacting with a central part thereof for removing it from said slot; and automatic means for returning the key to its normal position projecting into said slot as soon as said moving means has been released.
7. In a selflowering lifting jack provided with a steep pitch screw, a supporting easing having an elongated vertical opening therein with fiat parallel sides, and a vertically movable ram in said casing having a peripheral slot extending lengthwise thereof, said ram being freely movable downwardly on said screw when the screw is at rest; a fiat sided key slidable in said opening between the side walls thereof and extending normally into said slot, said key having midway of its length a headed projection; means coacting with one side of the head of said projection for removing said key from said slot; and a spring coacting with the opposite side of the head for forcing inwardly said key and moving means.
8; In a self-lowering lifting jack provided with a steep pitch screw, a supporting casing having an elongated vertical opening therein with parallel fiat sides and a vertically movable ram in said casing freely movable downwardly on said screw when at rest and having a flat sided peripheral slot extending lengthwise thereof; a fiat-sided key freely movable in said opening in contact with the side walls thereof; a stud centrally disposed in said key; a spring coacting with said stud to project a portion of said key into said slot; and an actuating lever movable about a pivot at the top of said opening and depending therefrom and having a hole therein through which said stud extends, said stud having ahead bearing on the outer face of said lever.
9. In a self-lowering lifting jack provided with a steep pitch screw, a supporting casing having an elongated vertical opening therein with parallel flat sides and a vertically movable ram in said casing freely movable downwardly on said screw when at rest and having a flat sided peripheral slot extending lengthwise thereof; a fiat-sided key freely movable in said opening in contact with the side walls thereof; a stud centrally disposed in said key and provided with ahead on its outer end; an actuating lever pivoted at its upper end with its central portion interposed between said key and head; and resilient means for normally forcing a portion of the key into said slot.
10. In a self-lowering lifting jack provided with a steep pitch screw, a supporting casing having an elongated vertical opening therein with parallel flat sides and a vertically movable ram in said casing freely movable downwardly on said screw when at rest and having a peripheral 7 slot extending lengthwise thereof; a flat-sided key freely movable in said opening between parallel ears projecting from said Casing; a closing plate secured to said ears and closing the upper and outer ends of the space between said ears; a stud centrally disposed in said key and provided with a head on its outer end; an actuating lever pivoted at its upper end to said ears and depending from said pivot with portions thereof between said key and head and its lower end extending slightly below said closing plate; and resilient means between said head and plate for forcing a portion of said key into said slot when said lever is released.
11. In a self-lowering lifting jack provided with a steep pitch screw, a supporting casing and a vertically movable ram in said casing freely movable lengthwise of the screw when the screw is at rest, said ram having a flat-sided vertical slot extending lengthwise of its periphery; a flat sided key movable in a straight path in contact with the side walls of an opening in said casing and adapted to partially enter said slot to prevent further rotation of said ram; a manually actuated member for withdrawing said key from said slot; and a spring in the same plane with the key for forcing said key inwardly when said member is released.
12. In a self-lowering lifting jack provided with a steep pitch screw, a supporting casing and a vertically movable ram in said casing freely movable lengthwise of the screw when the screw is at rest, said ram having a flat-sided vertical slot extending lengthwise of its periphery; a flat-sided key positioned in an opening in said casing and adapted to partially enter said slot to prevent further rotation of said ram; said key being movable radially to the axis of said screw and in contact with the opposite vertical walls of said opening; a depending manu ally actuated member for withdrawing said key from said slot, said member being pivoted to said casing near the top of the key; and a spring for forcing said key inwardly against the periphery of the ram when said member is released and impart further inward movement thereto when said slot and key are int-he same plane.
Signed at Harvey, 111., this 1st day of February, 1926.
FRANK L. GORMLEY.
US86418A 1926-02-06 1926-02-06 Lifting jack Expired - Lifetime US1680514A (en)

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