US1040386A - Hoisting device. - Google Patents

Description

H. A. MYERS. HOISTING DEVICE.

APPLICATION FILED OUT. 23, 1911.

1,040,386. Patented 0013.8, 1912.

HUBERT A. MYERS, OF GOSI-IEN, INDIANA.

HOISTING DEVICE.

Specification of Letters Patent.

Patented Oct 8, 1912.

Application filed October 23, 1911. Serial No. 656,240.

T 0 all whom it may concern Be it known that I, Hunnnr A. MYERS, a citizen of the United States of America, and resident of Goshen, Elkhart county, Indiana, have invented a certain new and useful Improvement in Hoisting Devices, of which the following is a specification.

. My invention relates to hoisting devices of the kind ordinarily known as hay cars.

A device of this kind, as is well known, comprises a sheave for the hoisting rope, and an automatic mechanism for cooperating with the said sheave to grip the rope and prevent the load from falling when it is desired to keep the same suspended in an elevated position. Thus, for example, the hoisting rope can be operated to elevate load and then when the pull on the rope is relaxed the said mechanism cooperates with the sheave to grip the rope and hold the load in an elevated position. After the load is removed, the said mechanism is then controlled, in various ways, to free the rope and allow the same to descend for another load. It is old, for example, to control the said mechanism merely by the forward and backward motion of a hoisting rope itself, whereby an auxiliary rope for controlling the said mechanism is not necessary.

My invention relates more especially to a hoisting device of this particular character.

The object of my invention is, therefore, to provide a hoisting device of this kind in which the so-called clutch mechanism that cooperates with the sheave to grip and hold the hoisting rope is of a simplified and highly efficient character, and in which improved and reliable means are provided for enabling the operator or user to employ the hoisting rope for controlling the said mechanism, as will hereinafter more fully appear.

To these and other useful ends, my invention consists in matters hereinafter set forth and claimed.

In the accompanying drawings-Figure 1 is a side elevation of a hoisting device embodying the principles of my invention, showing one side or half of the casing or housing removed to bring into view the sheave and clutch mechanism inclosed thereby, and showing the yoke of said clutch mechanism in vertical section. Fig. 2 is a vertical section on line 2-2 in Fig. 1, the sheave and clutch mechanism, however, being shown in elevation. Fig. 3 is an enlarged fragmentary perspective of a portion of the said clutch mechanism.

As thus illustrated, my invention comprises a casing or housing A of any suitable, known or approved character. It is preferably made in two parts, and so formed as to provide slots or openings (4 for the manipulation of the hoisting rope. The said casing or housing is held together by a bolt B which serves as an axle or journal for the sheave C, the ends of said bolt being provided with suitable nuts 5 by which the two parts of the housing are clamped together. The said sheave is of ordinary character, except that it is provided with laterally projecting lugs c that are formed with rounded portions 0' at one end thereof, and with beveled portions 0 at the other end thereof. The yoke D straddles the said sheave, and has the lower ends of its two arms pivoted at (Z to the sides of the casing or housing. The said yoke is curved outwardly and upwardly from said pivotal point cl, so that its upper portion cZ may overhang the sheave, a shoe or clutch block (Z being pivoted in the upper portion of the yoke immediately below the said top portion cl thereof. Movement of the yoke D to the left will, of course, bring the shoe (Z downwardly upon the hoisting rope on the sheave. Movement of the said yoke in the opposite direction is limited by a pin or stop (Z on the inside of the casing or housing. The yoke is provided at opposite sides thereof with inwardly projecting vertically disposed flanges (1 which are adapted to cooperate with the lugs c in causing the shoe (1 to bear hard upon the hoisting rope when it is desired to hold the latter stationary. When the sheave C is rotated to the right or in a clock-wise direction, the lugs 0 will engage and pass under the lower ends of the flanges (1*, thus producing no mechanical effect; but when the rotation of the sheave is reversed, and when it is moving in the direction shown by the arrows, then the beveled portions 0 of said lugs will strike and slide upon the flanges d", thus producing a wedging action that must necessarily result in forcing the shoe (Z very forcibly and powerfully against the hoisting rope on the sheave. l/Vhen this is done, the parts are automatically wedged or locked in such condition that the hoisting rope is held stationary.

It is, of course, necessary that at times the hoisting rope be allowed to travel clownwardly to the ground, either to obtain a load or deliver one, and at such time the sheave must rotate in the direction indicated by the arrows in Fig. 1. At such time the yoke D and shoe (Z must be locked in an inoperative position, as shown in Fig. l, and for this purpose certain locking mechanism is employed as follows: The lower end of the yoke D is formed at one side with a bifurcated finger (Z and in the slot (Z thereof a plate d is pivoted to swing freely back and forth. A dog or locking pawl E is pivoted upon the inside of the casing or housing and is provided with a portion 0 adapted to engage the finger (Z to hold the parts in the condition shown in Fig. 1. This dog or pawl E is fulcrumed between its ends, and its longer or rear end is provided with a pivoted element 6, the motion of which in one direction is limited by a pin or stop 6 on the said dog or pawl. For operating the element 6, to cause it to swing upwardly and engage the pin or stop 6 the sheave is provided with pins or projections 0 and the element 0 is preferably bent inward to project into the path of these pins or projections on the sheave. Now the parts as shown in Fig. 1, the sheave C can revolve freely in the direction indicated by the arrows, thus permitting the weight carrying portion of the rope to descend to the ground. This is by reason of the fact that the dog or pawl E is at this time in looking engagement with the finger (Z whereby the shoe or clutch block (Z is prevented from moving down upon the rope on the top of the sheave. hen the motion of the sheave is reversed, for the purpose of hoisting the load, or for the purpose of hoisting the carrying portion of the rope to obtain a load from overhead,

one of the pins 6 will then strike the element (2 and cause the latter to swing around until it engages the pin or stop 6 thus making it impossible for the sheave to rotate farther in this direction without disengaging the dog or pawl E from the finger 6Z5 on the lower end of the yoke. As soon as this is done, which results also in a consider-- able downward movement of the portion 6, the yoke D and the shoe (Z will tend to fall forward, or to the left, but the lugs 0 will bump on the lower ends of the flanges (l and thereby keep the said yoke in substantially the position shown in Fig. l, as this is necessary in order to permit the said lugs a to pass below the lower ends of the said flanges. During this time the plate or element (Z is hanging downward and blocking the engagement of the hook portion 6 with the finger cZ -that is to say, the hook portion 6 is at this time in engagement with the lower curved edge of the plate or element (Z whereby no locking action at this time can take place. When the load has been elevated to the desired extent, or when the load carrying portion of the hoisting rope has been brought to the position necessary for obtaining a load from above, the operator or user then relaxes the pull on the hoisting rope. This, of course, and owing to the fact that the portions 6 and 6Z5 are not at this time in looking engagement, causes the beveled portion 0 and the lugs c to ride upon the flanges (Z until the shoe or clutch block 6Z2 is brought down upon the hoisting rope on topof the sheave. This wedging action, as previously explained, blocks or prevents the further motion of the sheave in the direction indicated by the arrows, and holds the rope stationary. At this time the portion CF is out of the way of the portion (2, so that the said portion 0 does not engage the edge of the plate or element d, and consequently the other end of the dog or pawl E, which is heavier than the portion 6, drops down and thereby carries the portion 6 into a slightly elevated posit-ion. Now, when it is desired to again lower the hoisting rope for another load, or to deliver the load received from above, it is necessary to first pull on said rope to thereby rotate the sheave to the right, or in a clockwise direction, to an extent sufiicient to push the yoke into a vertical position and thereby bring the portions (Z and 6 into locking engagement, this being pos sible by reason of the fact that in this operation the portion 6 will engage and slide under the portion (Z and will thus engage the element 61 and push it backward and out of the way, as shown in Fig. 3. The parts are thus again locked in the posit-ion shown in Fig. l, and the rope may now descend for another load, or to deliver the load from above, depending upon the character of the work. At such time the pins 6 strike the element 6, but as the latter is free to swing backward or to the right, and is curved on the edge where the pins strike, no mechanical effect is produced, and the rotation of the sheave is not retarded or in any way interfered with. Then as soon as the rotation of the sheave is reversed, and the above described operation repeated, the portions d and e are again disengaged and the operation is then exactly as before.

From the foregoing it willbe seen that I provide a hoisting device in which the automatic clutch mechanism is controlled entirely by the back and forth motion of the hoisting rope, and through the medium of a simplified and reliable construction. In this way an auxiliary rope is not necessary, and the entire operation is controlled by the same rope which carries the load.

Preferably, a spring F connects the ele ment E with the casing A, as shown in Fig. 1, whereby said element normally engages the stop pin. f on the casing, but is operated against the tension of said spring by the finger d which latter is beveled to slip into and out of the hook e, in the manner explained.

It will also be seen that the plate (I is preferably provided with a pin d that strikes against the lower or outer edge of the finger d, to limit the swing of the plate (1 into the slot at, whereby the previously described operation is insured.

What I claim as my invention is:

1. In a hoisting device, a sheave for the hoisting rope, a yoke that straddles the sheave, a shoe or clutch block on said yoke, adapted to engage the hoisting rope to hold the same and the sheave stationary, flanges on the yoke, lugs on the sheave for engaging said flanges, locking mechanism for holding the yoke in position to prevent said shoe or clutch block from engaging the said rope, and means on said sheave for controlling the said mechanism by the back and forth motion of said hoisting rope.

2. In a hoisting device, a sheave for the hoisting rope, a yoke that straddles the sheave, a shoe or clutch block on said yoke, adapted to engage the hoisting rope to hold the same and the sheave stationary, flanges on the yoke, lugs on the sheave for engaging said flanges, locking mechanism for holding the yoke in position to prevent said shoe or clutch block from engaging the said rope, means on said sheave for controlling the said mechanism by the back and forth motion of said hoisting rope, said mechanism comprising a pivoted dog, means on said yoke for engaging said dog to hold the said shoe or clutch block away from the hoisting rope, a pivoted element on said dog, which element is adapted to be engaged by said means on the sheave to disengage the dog from the yoke, and means on said yoke for preventing the dog from engaging the yoke while the sheave is rotating in one direction.

3. In a hoisting device, a sheave for the hoisting rope, a yoke that straddles the sheave, a shoe or clutch block on said yoke, adapted to engage the hoisting rope to hold the same and the sheave stationary, flanges on the yoke, lugs on the sheave for engaging said flanges, locking mechanism for holding the yoke in position to prevent said shoe or clutch block from engaging the said rope, means on said sheave for controlling the said mechanism by the back and forth motion of said hoisting rope, said lugs being so formed that they pass under the lower ends of said flanges when the sheave rotates in one direction, and said lugs being formed with beveled end portions which enable them to engage and ride upon the said flanges when the sheave rotates in the opposite direction.

Signed by me at Chicago, Illinois, this 11th day of October 1911.

I-IUBERT A. MYERS.

Witnesses:

S. LEWIS, Gno. F. SCHMIDT.

Copies of this patent'may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. C.

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