US1487848A - Hoist - Google Patents

Description

March 25 1924.

W. A. GOLLNAST HOIST Filed June 29. 1921 4 Sheets-Sheet 1 March 25 1924:.7 1,48%@4 W. A. GOLLNAST HOIST Filed June 29, 1921 4 she'etssheet 2 @WMM a 4 Sheets-Sheet 5 W.A.GOLLNAST March 25v 19242a HOIST Filed June 29.

ASZSZ 1921 4 Sheets-sheet 4 w. A. GOLLNAST HOIST Filed June 29 March 25 1924.

Patented Mer. 25, i924.

hihiiTr STTELS WILLIAM A. GOLLNAST, OF VALLEJO, CALIFORNIA.

HOIST.

Application filed June 29, 1921.

17 10 all whom t may concern.'

Be it known that T, Trimmer fr. GoLLNAsT, a citizen of the United States, residing at Vallejo, in the county of Solano and State of California, have invented new Vanduseful Improvements in Hoists, ofvwhich the following is a specification. Y

This invention relates to a hoist, and particularly pertains to a safety device therefor. Heretofore numerous accidents have occurred in the operation of heavy h'oists, such as lock cranes, due to the fact that the boom hoist shaft was not positively engaged and thus allowed the crane to fall with its burden.

It is a principal object of the present invention to provide automatic and positively operating meanswhereby the disengagement of the hoist shaft from the main drive shaft will be accompanied by a positive locking of the boom hoist shaft.

The present invention contemplates the use of jaw clutches to operatively establish driving connection between the main drive shaft and the boom hoist shaft, and which clutches are actuated by means controlling a lock device acting upon the boom hoist shaft to prevent counter-rotation thereof. The invention is illustrated by way of example in the accompanying drawings in which F ig. 1 is an enlarged fragmentary view in elevation showing the safety mechanism with which the present invention is concerned, and particularly disclosing the lock pawl as in itsV operative position;

F ig. 2 is a fragmentary view in plan show ing the parts disclosed in Fig. 1;

Fig. 3 is a View similar to thatsh'own in Fig, 1 illustrating the inoperative position of the lock pawl;

Fig. 4 is a view similar to Fig. 3 showing the automatic safety action of the lock pawl when the jaw clutches are not positively engaged.

In referring to the drawings it will be understood that only the parts ofv a boom hoist mechanism are shown with which the present invention is concerned, and that the general construction andarrangement of the hoist is non-essential to the safety device here disclosed, this device being applicable to numerous hoist and driving mechanisms.

Broadly considered, the invention is concerned with a main drive shaft 10 acting through gea-rs 11 and 12 toV drive a boom hoist shaft 13, As shown in the drawings,

Serial No. 481,250.

these shafts are disposed at right angles to each other. The gear 11 is fitted with a hub 14 carrying clutch jaws 15. These aws are adapted to be engaged by jaws 16 of a sliding clutch member 17. The clutch member is splined onto the shaft 10 by a key 18. The hub of the sliding clutch 17 is formed with an annular groove carrying pins 19 of a shifting yoke 20, The shifting yoke is mounted on a fulcrum pin 21 supported from a fixed lug 22 forming a part of the main frame of the structure. with the shifting yoke 20 is a safety finger 23. This linger is adapted to oscillate simultaneously with the yoke as. actuated by a lever arm 2st. lin operating rod 25 is pivoted to the end of this lever arm, said rod being actuated by any suitable control mechanism. The safety iinger 23 extends substantially horizontally and is formed with a downturned end 26. This member is adapted to actuate a safety pawl 27. This pawl is mounted upon a pin 28 carried by a pad 29 supported on one of the main frame members of the hoist, as indicated at 30. This pawl is formed integral with a counterweight arm 31 which carries a weight 32 by which the pawl will normally beheld out of engagement with the ratchet teeth of a locking disc 33. This disc, as shown in Figs. 1, 3 and 4, is formed with av plurality of equally spaced ratchet teeth arranged around the circumferential edge. The disc is keyed to the boom hoist shaft 13 and the teeth are so, formed as to prevent counter-rotation of thislshaft when they are engaged by the paw It often happens that the jaws of the clutch members 14.- and 17 do not properly engage or dis-engage and that the pawl will only be in slight engagement with the teeth of the ratchet. ln order to prevent this and insure a positive locking action on the part of the pawl, an emergency cle-tent 33EL is pivoted to the back of the pawl by a pin 34. This detent stands substantially parallel to a lug 35 projecting from the back of the pawl and which lug has an end face adapted to register with the end face of the extension 26 when the members are as shown in Fig. 1. Tn the event, however, that the clutch jaws do not properly register, the pawl will be yieldably held by pressure of vthe safety finger extension 26 against the detent 33a. This detent. is fitted with a compression spring 36 passing around a bolt Formed integralV 37, which bolt tends to normally hold the detent against the lug 35, as shown in Figs. l and 3. Y

In the operation of the present invention, the mechanism here disclosed may be installed as a part of a boom hoist equipment with the ratchet disc 32 fixed upon the boom hoist shaft and Vthe jaw clutches mounted upon the main drive shaft. When it is intended to disconnect the two shafts, the bar 25 is drawn in the direction of the arrow a, as indicated in Fig. 3, thus pressing the end of the safety linger 23 down against the upper flat face of the detent 33a. Simultaneously with this action, the shifting yoke 2O will swing in the direction of the arrow b, thus moving the clutch member 16 from engagement with the jaw l5. If the separation of the jaws is complete the downward action of the member 26 againstthe detent will cause the pawl to swing in the direction of the arrow 0 until the flat face of the member 26 hascleared the face 38 of the detent, after which pressure will be brought to bear against the upper flat face of the lug 35, thus tending to hold the pawl in positive engagement with a tooth of the disc, as indicated in Fig. l ofk t-he drawing. In the event, however, that complete disengagement of the clutch members is not effected, the boom shaft will still :revolve and the pawl may be relieved by action of the detent 33a. It will be evident that as the ratchet disc revolves it will tend to raise the pawl, and with all of the parts rigid, some parts would undoubtedly be broken. However, due to the action of the detent, a raising action of the pawl will cause the detent to engage the side face of the member 26 and swing in the direction of the arrow d, as indicated in Fig. 4:. This swinging action will be against the compression of the spring 36, thus insuring that when the tooth has cleared the end of the pawl the spring will instantly force the pawl into the gullet of the tooth and cause the part-s to assume the position indicated in Fig. l. Analysis will also show that the detent will insure positive engagement of the teeth by the pawl, even though the clutches are actuated at an instant when the pawl and teethare not in direct engagement, the detent and of one of said members will cause actuation of the other, and vice versa, to positively in'- sure that the dis-connection of the boom hoist from the main drive shaft will be accompanied by a locking action of this hoist to continuously support the boom and thereby prevent accidents, all of which action is brought about by a comparatively simp-le and easily operated mechanism.

Tvlhile I have shown the preferred form of my invention, it is to be understood that various changes may be made by thoseY skilled in the art without departing fromthe spirit of the invention.

Having thus described lmy invention, what I claim and desire to secure by Letw ters Patent is:

l. In a device of the character described; a driveshaft; Va freely rotating gear thereon; a driven shaft carrying a fixed gear in constant mesh with said rotating gear; clutch means on the driving shaft for optionally engaging the freely rotating gear with said shaft; lock means on the driven shaft forv preventing counter-motion of the driven shaft; and `means for. simultaneously controlling the clutch mechanism and theloclr means Vwhereby disengagement clutches will cause operation of the lock means.

2.'.In a hoist mechanism, a main drive shaft, a boo-1n hoist shaft adjacent thereto; constantly meshing gears carried by said shafts for imparting movement from the main drive shaft to the hoist shaft in a given direction; clutch means carried by the main drive shaft for operatively connecting the Ydrive shaft with its gears; a ratchet mechanism associated with the boom hoist shaft to prevent counter-rotation of said shaft; and control means for simultaneously dis-engaging the clutches and engagingthe ratchet mechanism. 'V

3. In a hoist mechanism; a mainV drive shaft; a boom hoist shaft adjacent thereto; constantly meshing gears carried by said shafts for imparting movement from the main drive shaft to the hoist shaft in a given direction; clutch means carried bytheY of the Y llO hoist shaft; a complementary gear freely vmounted upon the drive shaft and in constant mesh therewith; a clutch mechanism for operatively connecting the freely mounted gear to the main drive shaft; a ratchet disc upon the boom shaft; a pawl adapted to prevent counter-rotation of said disc;

means for simultaneously and alternately rendering the clutch and ratchet mechanisms operative; and means for causing the ratchet mechanism to become locked irrespective of the relative positions of the ratchet disc and the pawl at the time the clutch mechanism is actuated.

6. ln a boom hoist; a drive shaft; a boom hoist shaft disposed at right angles thereto; a bevel gear keyed to the end of said boom hoist shaft; a complementary gear freely mounted upon the drive shaft and in constant mesh therewith; a clutch mechanism for operatively connecting the freely mounted gear to the main drive shaft; a ratchet disc upon the boom shaft; a pawl adapted to prevent counter-rotation of said disc; means for simultaneously and alternately rendering the clutch and ratchet mechanisms operative; and means for insuring that the pawl will positively engage the ratchet disc until the clutch members are absolutely in or out of engagement.

7. ln a boom hoist mechanism; a main drive shaft; a bevel gear freely mounted thereon; a jaw clutch element carried by said gear; a jaw clutch elementJ splined to the main drive shaft; a shifting yoke for moving said splined clutch member into and out of engagement with the first named clutch; a bevel gear in constant mesh with said freely mounted gear; a boom hoist shaft to which said gear is keyed; a ratchet disc fixed upon said shaft to prevent counter-rotation thereof; a paWl for engaging the teeth of said ratchet and normally held out of engagement therewith; and a lever simultaneously operated with the shifting yoke for alternately throwing the clutch members and the pawl and ratchet into and out of their engaged positions.

8. In a boom hoist mechanism; a main drive shaft; a bevel gear freely mounted thereon; a jaw clutch element carried by said gear; a jaw clutch element splined to the main drive shaft; a shifting yoke for moving said splined clutch member into and out of engagement with the rst named clutch; a bevel gear in constant mesh with said freely mounted gear; a boom hoist shaft to which said gear is keyed; a ratchet disc fixed upon said shaft to prevent counter-rotation thereof; a pawl for engaging the teeth of said ratchet and normally held out of engagement therewith; a lever simultaneously operated with the shifting yoke for alternately throwing the clutch members and the pawl and ratchet into and out of their engaged positions; and a spring detent carried by the pawl for permitting yielding movement thereof when the clutches and ratchet mechanism do not happen to register in synchronism.

9. hoisting and like apparatus including a drive shaft; a freely rotatingV gear thereon, a driven shaft, and fixed gear in constant mesh with said first named gear, clutch means on the driving shaft to engage the freely rotated gear, with its shaft, lock means on the driven shaft to prevent counter movement of the driven shaft when the clutch is disengaged1 and means for simultaneously controlling the clutch; and the lock means; whereby disengagement of the clutches will cause operation of the lock means. l

lO. A hoisting and like apparatus comprising a drive shaft7 a boom or like shaft adjacent thereto; constantly meshing gears upon said shafts to impart movement from the main drive shaft to the hoist shaft in either direction, clutch means upon the main shaft to operatively connect the drive shaft with its gears; a ratchet mechanism associated with the boom hoist shaft to prevent counter rotation of said shaft when the clutch is disengaged, and control means for simultaneously disengaging the clutches and engaging the ratchet mechanism.

l1. A hoist and like mechanism comprising a main drive shaft; a boom hoist shaft, contiguous thereto, constantly meshing gears upon said shafts to impart movement from the main shaft to the hoist shaft in either direction, clutch means carried by the main drive shaft to operatively connect it with its gear, a ratchet mechanism upon the boom hoist shaft to prevent counter rotation of said shaft when the clutch is disengaged or imperfectly engaged, control means for simultaneously disengaging the clutches, and

engaging the ratchet mechanism, and means to accommodate variation in the action of the clutches and registry of the ratchet and its pawl.

l2. In a boom hoist and the like, a drive shaft and a boom hoist shaft disposed at right angles thereto, a bevel gear keyed to the boom hoist shaft; a complementary gear freely turnable on thedrive shaft and in constant mesh with the first named gear; a clutch for operatively connecting the freely mounted gear to the main drive shaft, a ratchet disk upenn the boom shaft; a pawl to engage and prevent counter rotation of said disk, when the clutch-is disengaged, or

lock the ratchet irrespective of the relativel posit-ions 'of thel disk and pawl when the clutch is actuated. Y

13. 1n a boom hoist and like mechanism,

la main drive shaft, a bevel gear freely mounted thereon, a jaWclutch element, carried hy said gear, a jaw clutch element splined to the main drive shaft, a shifting yoke for moving said splined clutchmemher into and out of engagement with the iirst named clutch, a bevel gear, a boom hoist shaft to which said gear is keyed, and in constant mesh with the main shaft gear, a ratchet disk lixed to the boom hoist shaft, and a pawl 'to permit counter rotation thereof when the clutch is disengaged, or not properly engaged, said paw] being normally held ont of engagement with the ratchet,

and alever andshifting-yoke to alternately throu7 the clutch members and the paw-l and ratchet into and vout c-engagement.V

14. lna hoist mechanism, a drive and boom hoist shaftswith loose and ,fast intermeshing gears, a. clutch land actuating bar, a latchet fixed to the boom hoist shaft, aI pawl engaging said ratchet, a lug lprojecting fromvthe back of the-pawl, and a finger movable With the clutch actuating bar, to be moved into contact with vsaid lug.

\ 15. lny a-hoist mechanism a drive shaft and a boom hoist shaft with loose and fixed intermeshing gears, a clutch .and an actuating har, a ratchet fixed to the booinhoist Y shaft, a paWl engageable with said ratc :het, a lug upon the back of the paw-l and a, spring pressed detent pivoted therewith and affinger movable in unison With lthe actuating har, to engage Ithe det-ent and the lug on the pawl.

WILLIAM A. GGLLNAST. i

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