US1903633A - Gate - Google Patents

Description

April 11, 1933. F B, PEEBLES 1,903,633

GATE

Filed Dec. 9, 1950 2 Sheets-Sheet 1 INVENTOR' lil'lPeeZles ATTORNEYS April 11, 1933 F. B. PEEBLES QATVE Filed Dec. 9, 1950 2 Sheets-Sheet 2 BY 9 QM ATTORNEYS Patented Apr. 11, 1933 UNITED STATES PATT OFFICE I FRANK B. PEEBLES, F HUDSON, NEW YORK, ASSIGNOR TO GIFFORD-WOOID COMPANY, OF

HUDSON, NEW YORK, A CORPORATION OF NEW YORK i GATE Application filed December 9, 1930. Serial No. 501,115.

This invention relates to improvements in gates of the type used to control the flow of fluent materials, such as coal, sand, gavel and the like; and, among other objects, the invention aims to provide an improved gate having means to obviate spillage of the material which may occur just before the gate reaches its closed position.

The present invention may be employed with the gate described and claimed in the Hallenbeck application, Serial No. 355,517 filed April 16, 1929 or with the gate disclosed in the Root application, Serial No. 78,163 filed December 29, 1925, both of which are assigned to the assignee of this application. a

In the accompanying drawings showing a preferred embodiment of the invention,

Fig. 1 is a vertical, longitudinal sectional View of a bucket loading pit and hopper showing the improved gate in elevated or closed position and showing the bucket just before it trips the gate latch;

Fig; 2 is a vertical section through the r chute which forms a part of the gate;

Fig. 3'is a view similar to Fig. 1, but showing the gate open and the chute in bucket loading position; and

Fig. 4 is an end elevation of the parts shown in Fig. 2.

Referring particularly to the drawings, the bin or hopper 10 has an outlet 11 with a spout or chute 12 secured to the bin and extending downwardly and outwardly from the outlet 11 so that the contents of the hopper may be discharged by gravity. The chute 12 extends into a pit 13 and a traversing hoist bucket 14 is adapted to be lowered into the pit in a position to receive material discharged from the hopper. Instead of a pit, an above-ground pocket may be employed when the contour of the ground permits.

The bucket is guided into and out of the pit by means of rollers 15 arranged in two pairs, one on each side of the bucket, the pairs of rollers being engageable with spaced inclined tracks or guides 16 so that the bucket is maintained in upright position as it is elevated and lowered within the pit. The bucket may be hoisted and lowered by means of a cable 17 connected to any suitable hoisting mechanism (not shown) passing around a sheave 18 mounted on a bail 19 pivoted on the bucket. A suitable abutment 20 located in the path of the bucket effects closing of the doors or jaws 21 preferably when the bucket reaches filling position, substantially as disclosed in Patent No. 1,741,123 dated December 24, 1929.

The hopper is adapted to be closed by a gate of the radial undercut type, an example being the gate of the aforesaid Root application, and consisting of a pair of side frames 22 (only one of which is shown) pivoted on' opposite sides of the hopper, as at 23, and connected at their outer ends by a curved plate 24 which is curved coaxially with the pivots 23. The lower edges of the side walls of the chute 12 are correspondingly curved to conform to the inner surface of plate 24 and said plate is of such length that when it is raised, as shown in Fig. 1, the lower end of chute 12 is completely closed, thus closing the hopper.

the upper ends of the frames" 22 above the plate 24 so that when the gate is lowered to the position shown in Fig. 8, the material from the hopper flows through the chute 12 and also through the extension chute 25 into the bucket until the latter is practically full. A pair of flapper arms 26 are pivoted to the bottom of chute 2'5 and are connected by a cross rod 27, as best shown in'the above-mentioned Root application. When the gate is lowered (Fig. 3) the arms 26 are received within the bucket and when the bucket is first elevated, its edge engages the arms 26 to cause the cross rod 27 to be swungagainst As particularly described andclai-med in w. An extension chute 25 is rigidly secured to the above-mentioned Hallenbeck application, the gate is arranged to be normally closed and locked in closed position, and means are provided so that the gate will be unlocked by the bucket and will open by gravity as the bucket approaches filling position. To hold the gate in elevated or closed position, one or more latches 28 are provided, said latches projecting under the lower edge of the curved plate 24 when the gate is elevated, as shown in Fig. 1. Latch tripping means in the form of pivoted members 29 are mounted on the side frames 24 and directly engage the latches 28 when the gate is in closed position. The latch releasing members 29 are directly in the path of the upper edge of the bucket as it descends, as clearly shown in Fig. 1, and thus the bucket, by engagement with the latch tripping members, may move the latches out of the way of the plate 24, whereupon the gate and chute assembly 24, 25 swings downwardly by gravity into the position of Fig. 3. To control the gravity opening of the gate, a pair of ropes 30, only one of which is shown, are attached at one end to the extension chute 25 by means of ears 31, each rope passing upwardly over a sheave 32 at the top of the pit and downwardly around a guide sheave 33 mounted on the wall of the pit below the hopper, the lower end of each rope supporting counterweight 34. The weight of the gate assembly is greater than the effective weight of the counterweights 34 so that when released the gate falls by gravity into open position (Fig. 3).

The parts so far described form no part of the present invention except as they cooperate with the novel device which I provide to obviate spillage of material from the extension chute into the pit after the bucket starts to rise.

Referring to Figs. 2 and 4, the extension chute 25 is shown provided with a pivoted plate 35 which is preferably a heavy steel plate having its lower edge reinforced, as shown at 36. The plate 35 has a length sub- .stantially equal to the width of chute 25 but its width is preferably scarcely more than half the distance between the upper and lower walls of the chute. It is secured to two or more straps 37 which are preferably welded, the straps being pivoted on a rod 38 which is journaled at the top of the chute and spaced at considerable distance from the discharge end of the chute. When the gate is raised, as shown in Figs. 1 and 2, the plate 35 lies in an inclined position with its outer edge ad jacent the outer lower edge of chute 25. On the other hand, when the gate is lowered, the plate 35 tends to hang in a vertical position, as indicated in dotted lines in Fig. 3; but as the material flows out through the chute 25 with considerable force, the plate 35 will be lifted by the kinetic energy of the material until it may assume the full line position shown in Fig. 3. Varying rates of flow of the material being handled may cause the gate to assume a position intermediate the dotted and full line positions of Fig. 3. Thus the gate forms no obstruction to a free flow of material into the bucket.

When the bucket is first hoisted, it swings the gate upwardly by the engagement of the rod 27 with the underside of the chute 25, as previously explained. The chute 12 and the extension chute 25 may both be substantially full of material when the bucket starts upwardly. As the chute and gate assembly rises, the plate 24 is interposed between the lower end of chute 12 and the upper end of the extension chute 25 and thus cuts off the flow of material from the chute 12 into the chute 25. The material in the chute 25 continues to flow into the bucket as the bucket rises until the angle of the extension chute is less than the angle of repose of the material, whereupon flow ceases. The bucket usually clears the lower end of the extension chute at the moment when the angle of said chute is less than the angle of repose of the material. However, when handling such material as coal, the momentum of the material may cause a few lumps or fragments to continue to move downwardly even after the angle of the extension chute is less than the angle of repose of the material. These few last lumps may miss the bucket and fall into the pit below. As the bucket handles a very large tonnage of material in the course of a days time, it follows that an accumulation of a few lumps of material from each loading operation will soon form quite a pile in the bottom of the pit, and this pile, if allowed to grow, will prevent lowering of the bucket to a point at which it may be filled. Thus, operation of the entire plant may be stopped because of a spillage of a very small amount of material, if repeated at frequent intervals. The only remedy in the past has been to send a man down to the pit and laboriously clean out the pit by a hand shovel, an operation which necessarily shuts down the entire plant for the time being.

To obviate any possibility of spillage of material after the bucket clears the chute, the pivoted plate 35 is provided. This plate is so disposed that while the lower edge of the chute is still in contact with the upper edge of the bucket, the plate, which tends to hang vertically, will come in contact with the outer lower edge ofthe chute. As the plate is of considerable weight, this tends to check all flow of material and this tendency of the plate to stop flow is increased as the chute rises higher and higher because the weight of the plate becomes more and more effective as the chute rises to hold the material back in the chute; and furthermore the angle of the chute changes rapidly so that the angle of repose is quickly attained. The plate comes in con tact with the edge of the chute when the bot tom of the chute is at an angle of about 30 with respect to a horizontal plane, or an angle of about if the angle is measured in a counterclockwise direction. At this time the bucket has been hoisted only a few inches. The'momentum of some of the material may carry it momentarily out of the chute under the plate which yields to any force greater than its own weight but as the chute rises above the position wherein contact is first made between the plate and the lower edge of the chute, practically no material can flow out. The bucket remains in a position to receive material from the chute for an instant after the plate closes the chute and thus catches all material including that whose momentum is such as to push the plate to one side after the plate has closed the lower part of the chute. Ihe upper part of the chute is not closed by the plate because it is unnecessary, the described spillage always occurring from material which is in the lower part of the chute.

The described improvement has been found to stop nearly all spillage of material from the chute into the pit, with the result that it is unnecessary to stop operation of the plant while the pit is being cleaned out.

Obviously, the present invention is not restricted to the particular embodiment thereof herein shown and described.

What I claim is:

In combination with a fixed chute and a chute-like gate pivoted upon the fixed chute to swing vertically to stop and to permit flow of loose, fluent materials out of the fixed chute, a gravity-operated gate pivoted within the chute-like gate near the month thereof and at the top of said gate; said gravityoperated gate being as long as the chute-like gate is wide and being of such width as to close the lower part of the mouth of the chutelike gate; the location of the pivot axis of said gravity-operated gate being such, and the center of gravity of said gravity-operated gate being so disposed relative to the lower edge of the mouth of the chute-like gate, that whenever the chute-like gate is elevated to a point a few degrees below the horizontal, said gravity-operated gate will tend to engage said lower edge to close the lower part of said mouth, and said gravity-operated gate will remain in said chute-closing position during further elevation of the chutelike gate.

In testimony that I claim the foregoing as my own, I have hereto afiixed my signa ture.

FRANK B. PEEBLES.

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