US2720951A - Hoist - Google Patents

Description

G. W. OLSON Oct. 18, 1955 HOIST 4 Sheets-Sheet 1 Filed Aug. 5, 1949 6 801945 4/ Owe/v G. W. OLSON HOIST 4 Sheets-Sheet 2 Filed Aug. 3, 1949 H I kw 4 M W E a 00w mm 1 1 w 0. W E an m w s \w G a W MM W EVA? XE V NM m mwmw & 4km mm 7 "I \w G. W. OLSON Oct. 18, 1955 HOIST 4 Sheets-Sheet 3 Filed Aug. 5. 1949 MW 1 mg Oct. 18, 1955 G. w. OLSON 2,720,951

Filed Aug. 3, 1949 4 Sheets-Sheet 4 awe/whom GEORGE h. 0480 QMLM qumy o Unite This invention relates to improvements in power hoists or winches for use in lifting and manipulating loads of various kinds, and particularly useful for contractors in the construction of buildings to elevate materials and tools.

The present invention further relates to certain improvements in, and added equipment for enlarging the uses of, the type of portable, light duty hoist shown in my prior co-pending application, Serial No. 13,589, filed March 8, 1948, now Patent No. 2,633,940 and the present application is a continuation in part of that application.

The primary object here is to provide an improved brake and motor control mechanism for the hoist, by means of which it may be started, stopped and reversed, and the load suspended at any time. My portable hoist is an all-position machine, in that it in any one of a number of difierent positions about the job, and the improved brake mechanism here presented provides for convenient, instantaneous remote control under most all conditions.

Another object is to provide for the light duty portable hoist of my invention a frame assembly into which it may be readily and quickly mounted, with a second hoist or winch spool, and means for making a manually controllable drive connection to the hoist unit itself whereby the effective power is stepped up and heavier loads may be handled. Thus a contractor, by the use of the small hoist and auxiliary frame and winch, may inexpensively meet all of the requirements about the job, with a minimum of equipment.

Another object of and mounting features fitting it to do all of the jobs which may be required.

These and other more detailed and specific objects will be disclosed in the course of the following specification reference being had to the accompanying drawings, in which- Fig. 1 is a side elevation of a hoist construction according to my invention.

Fig. 2 is an enlarged detail sectional View of the jaw clutch for the drive connection between the hoist or winch spools.

Fig. 3 is a plan view of the hoist of Fig. 1.

Fig. 4 is a sectional detail view along the line 44 in Fig. 3.

Fig. 5 is an enlarged detail sectional view through the lock for the second hoist or Winch spool, taken along the line 5-5 in Fig. 1.

Fig. 6 is an elevation of the opposite side of the hoist construction.

Fig. 7 is a side elevation of the portable hoist unit alone.

Fig. 8 is an enlarged detail section along the line 88 in Fig. 7.

Fig. 9 is a detail of the brake mechanism, looking at the end of the hoist spool.

Referring now more particularly and by reference chartates Patent .hfice cable 26 run over an of the frame and trained over this fines of the frame. The

2,72%,951 Patented Oct. 18, 1955 acters to the drawing A designates generally the portable hoist portion of my present invention, and which is in many respects similar to that disclosed in my prior c0- pending application hereinbefore mentioned. This hoist unit A, which is selectively usable in conjunction with a second hoist and frame structure, designated generally at B, comprises a frame made up of two main side bars bent back upon themselves in rounded conformation to form semi-circular ends 10 and parallel legs 11 which are joined at a plurality of points by cross bars 12. The rounded ends 10 of the frame structure are joined by a tubular handle member 13 welded across the opposite sides of the frame to provide a convenient handle by which the hoist may be carried about the job. This handle member 13 also ties the respective side frames together, and additional cross ties are provided by means of cross bars indicated throughout at 14. Bearing plates 15 are secured across the semi-circular ends of the frame and carry bearings 16 at their centers in which is journaled a spool shaft 17 upon which a winch or hoist spool is mounted. The said spool comprises a center tubular arbor 18 and dished ends 19 which are welded to the ends of the arbor and carry bearings 20 pinned or otherwise suitably secured to the spool shaft 17 to rotate therewith. At one end of the spool a large sprocket gear 21 is secured to the shaft 17 to run within the rounded end sprocket is a chain 22 operating over a similar sprocket pinion 23 upon the drive shaft of an electric motor 24. The motor 24 is mounted by means of bracket bars 25', as seen in Fig. 3, to the cross bars 14, placing the motor wholly within the conhoist spool is, of course, adapted to accommodate a flexible cable or rope, as indicated throughout at 26, which may be run to the load so that upon rotation of the motor and the spool the load will be raised or lowered as the case may be.

As discussed in more detail in my prior application, the hoist unit thus constructed is readily portable and may be mounted in any one of a great number of positions about the job and according to the work to be done. For example, the hoist may be placed on the ground and the overhead tackle, or the hoist itself may be placed in an elevated position to operate directly upon the load, and remotely controlled from any desired position.

which I will now describe.

Referring particularly to Figs. 7, 8 and 9 it will be seen that upon the end of the spool opposite the driving sprocket 21 an annular brake drum 27 is secured concentrically to the outside of the spool end 19 by welding or other suitable mounting. The drum 27 has an interior lining 28 which cooperates with arcuate brake shoes 29 and 36 having overlapping ends 31 pivoted upon a pin 32 carried by the adjacent bearing plate 15. The opposite ends of the shoes 29 and 3t) are spaced apart to accommodate an actuating cam 33 which is carried at the inner end of a cam shaft 34 journaled out through a bearing 35 in the bearing plate. A light retractile coil spring 36 connects these ends of the shoes 29 and 30 and serves to normally draw them together and maintain them in contact with the cam 33. Outwardly of the bearing plate the cam shaft 34 has an arm 37 secured thereto and extending in opposite radial directions.

39 of a spring 4t), the opposite end of which is attached to a screw 41 fitted through a bracket 42 on the frame and provided with a thumb nut 4 The spring 40 is thus arranged to so turn the cam 33 as to normally spread the brake shoes 29 and 30 into engagement with the brake lining 28 and thus normally and yieldably set the brakes upon the spool. The effective tension exerted by the spring 46 to thus set the brakes may be adjusted by moving its hooked end 39 to any one of the series of notches 38, and more precise adjustments may be carried out by turning the thumb nut 43. The purpose of such adjustment will be presently made clear.

The opposite end of the arm 37 is pivotally attached to a pair of diverging link rods 44 and 45, as indicated at 46, and these link rods extend through pivotally mounted trunnions 47 at the opposite ends of a rocker member 48. The extremities of the link rods 44 and 45 are threaded to receive stop nuts 49 and between these nuts and the aforesaid trunnions the rods are also fitted with sleeves, indicated at The rocker member 48 is secured upon the extended end of a rock shaft 51 forming part of a motor control and reversing switch 52 secured to the adjacent side of the hoist frame. This switch 52 is of the type which is normally open, but is closed upon rocking movement of its shaft 51 in opposite directions, and the supply cord 53 by which the motor 24 is connected to its energizing source is connected to the switch. The motor 24 is of the reversible type while the switch 52 further in response to opposite rocking movements of its shaft 51 not only starts and stops but reverses the motor, and appropriate connections are made as indicated at 54 between the switch and the motor. The rock shaft 51 of the switch is journaled through a U-shaped or hairpin bracket 55 secured to the bearing plate as indicated at 56 and projects beyond to accommodate a control lever 57 secured to the shaft by means of a set screw 58 and extending in opposite direction from the shaft. The opposite ends of the control lever 57 are apertured so that control cables 59 and 64 may be readily attached and the set screw connection 5% permits the lever to be shifted angularly upon the rock shaft 51 so as to extend these cables in almost any desired direction.

It will thus be understood that the hoist spool is normally maintained in a braked condition by the action of the spring 40 and the parts are further so arranged that in this normal position of the brake mechanism itself the rocker member 48 will also be centered and the switch 52 held in its open position with the motor 24 de-energized. A pull upon the control cable 60, for example, will as shown in Pig. 1 then rock the member 48 in a clockwise direction until the trunnion 47 engages the stop sleeve and nut upon the link rod 45 whereupon a pull will be exerted through this link rod in such direction as to correspondingly turn the cam arm 37 and cam 33 to release the brake shoes 29 and 30 from the brake lining 28. As the brake is thus released upon the spool the motor 24 will be started to turn the spool in one direction and, as here shown, the spool will so rotate as to pay out the cable 26. A pull upon the other control cable 61 will oppositely oscillate the parts to release the brake upon the hoist spool and start the motor, but in the reverse direction, as will be readliy understood. The link rods 44- and 45 have a lost motion connection with the rocker member 48, and the amplitude of such lost motion is readily adjustable by means of the stop nuts 49 so as to precisely time the releasing of the brakes with respect to starting the motor in either direction. Thus I am able to remotely control the hoist in such manner as to start and stop the motor and lift or lower a load, or suspend it in any desired position, and the brake force applied may be readily adjusted, by positioning and tensioning the spring 4-0 according to the weight of the load being handled, to properly carry out the work. As an example, it is possible to so adjust the brake that a load of material may be lifted up upon a building and held suspended until the worker grasps the load and pulls it down into place, with the weight supported by the brake tension upon the hoist spool. It will be clearly evident that many possible variations in the placement of the hoist, and arrangement of the control cables, may be had in order to fit the hoist to almost any type of construction job.

Under certain circumstances increase the load capacity of the hoist, and I accordingly provide a second hoist and frame structure designated at B and hereinbefore referred to, for this purpose. This structure B comprises a frame made up of conventional angle iron material, including upper side bars 61 having inwardly turned webs 62 so spaced apart as to nicely accommodate the hoist legs 11 when the hoist is laid down between these side bars as shown in the drawing. This second frame structure also includes an end frame 63 with a cross angle bar 64 so spaced above the side bars 61 that the end of the hoist frame may be inserted beneath the horizontal flange 65 and held down by means of a set screw 66 in said flange. The second hoist structure comprises end panels 67 secured to the side bars 61 and provided with bearings 68 to accommodate the shaft 69 of a second winch or hoist spool, indicated at 70. At one end the shaft 69 is fitted with a large drive sprocket 71 over which is trained a sprocket chain 72 which may be arranged around a sprocket pinion 73 carried by the spool shaft 17 of the hoist. 24 may be connected through the intermediary of the hoist spool itself to the second winch spool 79 in order to drive the latter at a slower speed, but with greater effective lifting power, as will be readily understood. The winch spool 70 is, of course, arranged for the accommodation of a lifting cable 74 for handling the load attached thereto. In order to hold the driving end of the portable hoist unit down, bracket arms 75 are secured to the end panel 67 and extended across the opposite ends of the tubular handle member 13, where they are provided with slots 76 to receive cap screws 77. The ends of the handle member 13 are tapped to receive the screws 77, and the slots 76 permit the portable hoist unit itself to be so adjusted, prior to drawing up the cap screws,

it may be desirable to k as to properly tighten the drive chain 72.

The drive between the first and second winch spools is selectively engageable by means of a jaw clutch, the construction of which is best shown in Fig. 2. The sprocket pinion 73, by which the chain 72 is driven, has a hub 78 which is freely rotatable upon the spool shaft 17, but has clutch jaws at its end as indicated at 79. The

spool shaft 17 extends for some distance through this hub 78 and a keyway is formed in the shaft for the slidable accommodation of a spline or key 80 upon the collar 81 which, of course, thus rotates with the spool shaft. An expansion coil spring 32 is placed around the spool shaft between the hub 78 and collar 81 and acts to normally urge the latter in an outward direction axially of the shaft so that cooperating clutch jaws 83 upon the collar are normally disengaged from the jaws 79. A hand wheel 84 bears against the end of the collar 81 and has a threaded stem 86 screwed into a tapped bore in the spool shaft so that by turning this stem into the shaft the collar will be thrust inwardly and the jaws 79 and 83 engaged to establish the drive connection between the spool shaft and the chain 72 driving a second winch spool 70. Opposite movements of the hand wheel 84 will, of course, permit the spring 82 to disengage the clutch jaws and so disable this second spool drive connection.

When the second winch spool 70 is being used, the motor 24 will, of course, be controlled through the cables 59 and 60 exactly as previously described, and some braking effect will be provided by the brake mechanism associated with the motor control. However, on the average, heavier loads will be handled when the second spool 70 is in use so that braking effect may well be insufficient to maintain a load in a suspended condition. For this reason I provide the winch spool 78 with a positive mechanical lock which comprises a T-screw 87 which is threaded through the end panel 67 at the end of the assembly opposite the drive chain and sprocket. The screw $7 may thus be projected inwardly toward the ad- Thus the motor v jacent end of the spool 70, designated at 88 in Fig. 5, and this end of the spool is provided with a circular row of apertures 89 about its shaft 69 into any one of which the screw may be thrust. When so engaged it will be obvious that the spool 70 Will be positively held against rotation, but it may be, of course, released by turning the screw 87 outward to clear the apertures 89.

It will be evident from the foregoing that I have provided a hoist or winch construction which is exceedingly adaptable and which permits the contractor or other user to handle most all hoist jobs with a minimum of expense and equipment. The portable hoist A is, as stated, an all position affair, and even when assembled with the structure B, the hoist assembly may be operated either in the position shown in Fig. 1 or turned up upon the end frame 63 as may best suit the work at hand. The connection or disconnection of the portable hoist A to the structure B may be carried out quickly and with little work, and in many cases the structures A and B may be left in assembled condition, and the hoist spools used selectively according to the weight of the loads being handled.

It is understood that made in the structure as suitable modifications may be disclosed, provided such modifications come within the spiirt and scope of the appended claim. Having now therefore fully illustrated and described my invention, What I claim to be new and desire to protect by Letters Patent is:

For controlling a hoist unit having a spool rotated in opposite directions by a reversible electric motor, a reversing switch for the motor, a brake drum connected to rotate with the spool and brake shoes cooperating with the drum, remote control mechanism of the character to the cam, a spring connected to one end to bias the same in one direction to thereby of the arm actuate the whereby rocking movement of the rocker in either direction will cause one of said trunnion elements to engage one of said stop means to thereby move the arm in a direction for actuating the cam to disengage the shoes from the drum.

References Cited in the file of this patent UNITED STATES PATENTS

Images