US1776099A - Lifting jack for coal-cutting machines and the like - Google Patents

Description

sept. 16, 1930. l, 6,099

mums JAcx van coAL curns ucn'rnss un fnl' Lm yv. c. BLACK med oct. 1, 1921 z sheets-sheet' 1 Arwen/sy Sept. 16,1930. c. BLAcK l 1.776.099

LIFTING' JK FOR COAL CUTTING IGHINBS :um THE LIKE Fuga ont. 1, 1927 z sheets-sheet 2. 20 25 22 /NVENTC yfwm Patented Sept. 16, 1930 UNITED `s'rxras PATENT OFFICE WILLIAM CHRISTIE BLACK, orv DULLEY, ENGLAND, AssIeNoa To MATTHEW sMI'IH Y Moonnor BHUssELs,BHLGIUM f- LIFTING JACK non @OAL-CUTTING MACHINES AND THE LIKEV Application filed rOctober 1, 1927, Serial No.

The present invention relates to lifting jacks and it has particular reference to' screw jacks such as are used'coal cutting machines and the like,`in which it is required to move 5. the machine bodily in order to obtain the necessaryA vertical and angular adjustment of 4the tools to suitfvarying conditions of work.

p In machines of this kind it is customary to lo support the vframe or body of the machine on lifting jacks located on either side of its longitudinal" axis'," so that the frame may be raised or lowered when such jacks are oper'- ated together, or it'may be tilted to the de- 15 sired angle by'opera'ting only the'jack or jacks on one side thereof. In order that the jacks may follow the tilt of the frame they are conveniently mounted on spherical feet. However if they are rigid with the. machine frame, they have a tendency to'jam'when the machine is tilted and it has been proposed to allow one of the feet to slide laterally, causing allthe side stresses to bear on thefixed foot. In another case where both feet are 25. fixed, one jack only is held rigidly in the machine whilst the other is free to accommodate itself to the angle of tilt. ySuch arrangements, however, have certain inconveniences, and in particular that of weakening the support of the machine.

It is the object of my invention to obviate I these -inconveniences and to :provide lifting or adjusting jacks which will befreeof jamming and adapted to be rigidly held ina 35 machine frame without lrequiring any displacement of their supporting feet when the machine is tilted.

To this end the lifting jacks according to this invention are formed of two parts mountedeccentrically with respect to each other so as to'be capable of compensating by an angular motion a lateral displacement imparted to one of said parts. In the case of screw V jacks for coal cutting machines, the axis of the screw preferably extends parallel to that of the spherical foot. l/Vhen one of the jacks is operated to tilt the machine the screw automatically moves about the centre of such 50 foot through the angle required to absorby 223,442,1and`in Belgium l(Jcrsober 13, 1926i Vthe lateral movement corresponding to the' view of a coalcutting machine equipped with screw jacks according tothis invention. .f Fig. 3 shews a detail lin sectionon line A-B of Fig. 2. i Y

Figsli is a cross section, on an scale, taken on line Cf-D of Figi 2.

Figs. 5 and -6 illustrate a screw 'jack onv a still larger scale, Fig. 'being an `axial 'sec tion von line E--F of Fig. 6, and Fig. 6 a cross-section on line G-II of Fig. 5."

'In Fig. l, If'have'diagrammatically repreysented at l the frame ofa coal cuttingmachine of rectangular cross-section, supported by screw Jacks resting on spherical `feet 2. In known structures wherein the jacks are rigidly. held in the machine frame the axes of the screws coincide with the axes a of the sphericall feet vand if one only of the screws is operated the `frame is tilted` to a positionsuch as shown in dotted lines at 1, the axis of this screw taking .up theposition a, whereby the foot 2 supporting said Vscrew enlarged` v is caused to move laterally to the position'2.

' In the structure according to my invention this lateral displacement is avoided owing to the fact that the screws are mounted eccentrically to the spheres 2. Thus in Fig. 1 the vaxes of the screws are shown at and on the machines being tilted they will turn through any required angle up to 180o about the ce-ntres 0 of the spherical feet 2 and take 'up thepositions b', the frame taking upthe position 1/ .while the feet 2 remain stationary. VIn practice the axis a of each spher` ical foot and vthe .axis b ofthe correspond-l ing screw are comprised in the same longitudinalv plane (at right angles to the plane of Fig. l) so as toA permit of the axes b turning of the machine and on a pair of screw acks 4 mounted in the machine trame 1 and symmetrically located on either side of the longitudinal axis.

The support 3 may be of any suitable construction capable of allowing for universal movement of the trame within restricted limits. I have shown in Figs. 2 and 3 a rather crude but convenient support of current design consisting of a web 8 on the usual skid 5 supporting the entire machine. Through an eye 6 in this web extends a bolt 7 secured to the bottom wall 8 of the frame 1 which is recessed at9 to accommodate the Y web 3. The diameter of the eye 6 is substantially larger than thatof the bolt 7 and the recess 9k is proportioned so that the trame may have a certain freedom of oscillation about its longitudinal axis, in addition to' being able to swing about the pivot 7. 1 l

The screwjacks herein shown (Figs. 4to

E6) comprise each a screw 10 engaging'ran internaillylthreaded sleeve '11; Thecylindr'ical outer wall of this sleeve is concentric to the axis b of the screw 10 and has asnug y fit in a cylindrical rece-ssi'1v2in the; machine Ywith the spherical foot frame l. Thesleeve 11ijs "secured by means of appin 13 to a member or projection 14 rigid 2 Vsupporting "-thfe screw jack. y i l As illustrated, the axis ofthe screw `and sleeve is eccentric to the spherical bearing and extendsv'parallel to the axisa ojthe latter, theeccentricity being proportioned accordingk to the magnitude of `the` lateral movement to be absorbed.` The `foot* 2 'is mountedin'a bearing15, 16 which may be' secured in position on the supportingplate 5,

To provide the desired rigid connection with the machine frame the screw '10 has an kannular top shoulder 19 `and onits upper fend 20 is screwed a nut 21 lockedfby means of a pin 22. Between the shoulder 19 and nut 21 is comprised a plate 23 rigidly secured to theframe 1 by bolts 24. Accordingly when `the screw 10 is rotated in one or4 the other direction by operating its polygonal head 25, it will lift the trame by means ot the shoulder 19 or lower it by means of the nut 21. Y t

' It onetonly of the screw jaclsis operated the screws 10 will follow` the tilt imparted tothe frame. Since the spherical feet 2 are Y' prevented fromv sliding laterally, the sleeves 11 will turn each about the axis a of its toot,

t lthrough the angle required to compensate for l the lateral movement corresponding toy the tilt of the frame This angle of course should not exceed 180o since locking then would take place, but the eccentricity can be so proportioned that the lateral movement correspondingto any amount of tilt required in practice may be compensated for by a rotatable through an angle of.180 on anaxis 'parallel to the' axis of said bore; l 1K3; In a lifting jack Afor `coal cutting matation of less than 180, a rotation of about 90o being fully sufficient in most cases.

It will be understood that the particular construction herein described and illustrated may be varied without departing from the spirit of my invention, y

l claim:

1. In a lifting jack for coal cutting machines andY thelike, the combination of a member having a cylindrical bore 'therein,""a cylindrical member engaging said bore and capable bothot sliding and rotary motion therein, a supporting tootv Asecured to one end ot said cylindricahmember,--saidtoot being rotatable through an angle of 180o on an axis "eccentric to said bore,andmeans 4for moving memberlhaving a cylindrical boretherein, at

cylindrical sleeve, engaging said bore, l-said lsleeve being .internally screw-threaded,a

screw in threaded engagement with'jsaid sleeve,1 said screw being 'rotatably mounted in said* member and'lockedv against: axial" movement with respect-(thereto,4 and fasupporting 'toot .eccentrically' secured totthelower end of said sleeve,I saidfootbeing rochines and the like', the combination `ofa ing screw rotatably mounted in said member and locked against axial movement with` respect thereto, said screwbeing coaxial with said sleeve and said bore, and aspherical supportingftoot rotatable through an.y angle fof 180O on an axis'parallel to thevaxis ofsaid screw, said toot being secured tothe' lower end ofsaid sleeve.

4. In va lifting jack for coal cutting machines and the like, thezcombinationzot asta-y `tionary bearing, a vspherical-" tootl rotatable thfrough 180o in said bearin-g a cylindrical member resting on saidfoot, the axis of said cylindrical member being parallel-tothat-of said foot and bearing, a casing having a cylindrical bore surrounding said cylindrical member, and means interposed between said casing and sai'drcylindrical member for moving said casing` axially of said member.

5. In a. coal cutting machine, the .combi-na` tion with a frame having a pair of cylindrical bores, of internally threaded cylindrical sleeves slidable and rotatable ,eachl through an angleotl 180o in said bores,`co-operating screws rotatable in saidrframe and'glocked against axial movementv relative thereto, spherical supporting teetrsecured one to the lower end of each of said sleeves, said feet being rotatableeachon an axis parallelto, A l

that of the sleeve secured thereto; 'y

Vmember having a cylindrical bore therein, an internally Lthreaded cylindrical'A 4sleeve slidable and rotatable in said bore,aco-operatrice 6. In a Coal cutting machine, the combination With a frame having a pair of cylindrical bores, of a skid, a pair of spherical bearings fixed on said skid, a rotatable spherical foot in each of said bearings, a cylindrical member mounted eccentrically on each of said feet, each of said cylindrical members being slidably engaged and capable of rotation through 180O in one of said cylindrical bores,

and means interposed between said frame and each of said cylindrical members for lifting and lowering said frame With respect to either of said members.

WILLIAM CHRISTIE BLACK.

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