US2000150A - Excavator - Google Patents

Description

May 7, 1935.

H. SIE BERT EXCAVATOR Filed Jan. 27,1933

Inventor (0. 5.. W4. dttorney Patented I 7, I

I Umr.ap srArEs PATENT orrlcs EXCAVATOR Heinrich Siebert, Dnisburg,'Germany, assignor to Demag Aktieng'esellschait, Duisburg, Germany Application January 27, 1933, Serial No; 653,791 In Germany February 5,1932

8 Claim.

also connected to gearing for directing the shovel,

whereby when the extension of the hoisting cable is gripped, the shovel can be swung on the swing: mg of the haft-member while retaining its approximate position in space, the shovel being tipped and thus emptied when the extension of the hoisting cable is released.

The mechanism for directing the shovel consists essentially of a guiding quadrilateral which approximates to a pivoted parallelogram; this quadrilateral consists of the braking or gripping device, the lower arm of the haft-member, the shovel and the extension to the hoisting cable.

The instroke excavator according to the invention has the advantage that notwithstanding the range of movement of the shovel, two cables are in practice suflicient, namely the hoisting cable and the drag cable hereinafter described, that is to say there is the minimum number of cables and an extremely simple cable guide. Notwithstanding this simplification of construction, the shovel can be emptied in any position and accidental tipping of the shovel is eflectively avoided.

The invention is diagrammatically illustrated by way of example in the accompanying drawing, in which Figure 1 illustrates the method of controlling the shovel.

Figures 2 and 3 illustrate by way of example two constructions of the controlling apparatus. Figures 4 and 5 show two operative positions of the excavator according to the invention.

Referring to Figure 1 of the drawing, the haft member 3 of the shovel is rotatable about the pivotal axis 2 of the jib l of an instroke excavator. It is drawn by the drag cable 4 towards the excavator, while the haft-member I is moved by the hoisting cable 5 in the opposite direction. The hoisting cable 5 extends beyondthe pulley 6 mounted at the upper end of the haft-member 3 and is connected to the shovel I; this extension of the cable 5 is numbered in. The extension 5a may be held fast by a braking or-clamping member 8 provided on the jib I. Thus, if the haft-member 3 is moved, the shovel I maintains its approximate angular disposition in space. This is due to the fact that the shovel is carried by a. pivoted quadrilateral formed by the lower arm of the haft-member 3, the top edge of the side of the shovel I, the extension 5a of the hoisting cable and that part of the extension of the jib between the pivotal axis 2 and the braking or clamping member 8. If the braking or clamping member 8 is released, the shovel I can be tipped by means ,of the cable 5, and turns about the axis l8 until it strikes against the stop I.

Figures 2 and 3 illustrate in detail two constructions of braking device according to the invention. The reference numerals are for the most part the same as those in Figure 1. In Figure 2, the hoisting cable 5 is secured to a bell crank lever l0, which rocks about an axis 2, for

example the axis of the haft-member 3, but independently of the haft-member itself. A cable, chain or belt I 3, extends from the lower arm of the bell crank lever III to a drum H, which drum is provided with a brake, the brake band being numbered IS. The brake band I5 is under the influence of a pressure medium cylinder and piston it, which may operate for example with compressed air or steam, or water under pressure, or it may be controlled by an electro-magnet or by hand. The bell crank lever I is connected to the shovel 1 by a cable or rod H, which is connected to the shovel at II. If the brake holds fast the lever l0, and the drag cable 4 is slackened while the hoisting cable is tensioned, the haft-member 3 is rocked by the hoisting cable 5, while the shovel l retains its approximately horizontal position because the parts l0, 3, i and II form a pivoted parallelogram. If on the other hand the brake I5 is .released, the shovel I can be moved relatively to the haft-member 3.

The construction according to Figure 3 differs from that according to Figure 2 in that the lever I0 is replaced by a sector H, the hoisting cable 5 passing over the arc Ila of the sector while the cable l3 which extends to the drum l4 lies on the channel "b. The method of operation is substantially the same as that of the construction according to Figure 2.

Figure 4 illustrates the shovel shown in Figure 2 in the position reached near the end of the movement along the pit being excavated. The brake I 5 is first released, the drag cable I is then tensioned, while the cable 5 is slackened. The shovel is thus caused to move inwardly and to be filled.

The haft member 3 is now moved outwardly by the winding in of the cable 5 and the slackening oi the drag cable 4. The lever I0 is first secured by the brake band ll. If the bait-member 3 is rocked, the mechanism which determines the disposition of the shovel consisting of the parts 3, I, Iii and ii causes the shovel to retain approximately its angular disposition in space, so that the final position is more or less as shown in Figure 5. The shovel does not rotate with the hattmember I and thus the earth or other material ls prevented from falling out of the shovel when the hart-member 3 is moved. To empty the shovel I in the position illustrated in Figure 5, which need not be the extreme position, the brake band i5 is loosened so that the shovel I may be moved about the axis [8 to abut against the stop it by tensioning the cable 5.

Figures 1, 2 and 3 illustrate various modifications in construction of the braking or like device but it will be understood that the invention is not limited to the constructions shown which are given merely by way of example.

The important point is that the movement of the shovel relatively to the heft-member is in all positions under the control of the hoisting cable 5.

I claim:

1. An instroke excavator comprising a jib, hart member supported by and rotatable upon the said jib, a shovel movable relatively toand supported by the haft member, a braking element adjustable upon the said jib independently of the said haft member, a hoisting cable connected with the braking element and engaging the bait member, and a link between the braking element and the shovel such that the braking element being retained in fixed relation to the jib the bait member may be swung by the hoisting cable while the shovel retains its angular disposition in space.

2. An instroke excavator comprising a jib, a bait member pivoted at a point intermediate its ends upon the jib, a braking element upon said jib to which the bait member is relatively rotatable, means upon said jib for operating said braking element, a shovel pivoted to one end of the said haft member, a connection between the braking element and the shovel at a radius from the pivotal point of the shovel, a drag cable connected to said heft member, and a hoisting cable connected to the said braking element and engaging the haft member.

3. An instroke excavator comprising a jib, a bait member pivoted at a point intermediate its ends upon the jib, a braking element rotatable about the pivot of the bait member upon the said jib, a brake mechanism upon the said jib controlling the rotation of the braking element, a

shovel pivoted to one end of the said hart member, a link connected between the braking element and the shovel at a radius from the pivotal point of the shovel, a drag cable connected to said hart member, and a hoisting cable connected to said braking element and engaging the haft member.

4. An instroke excavator according to claim 3, in which the braking element is subjected to the control of the braking mechanism through a connection which engages the braking element with a leverage distinct from that applied by the braking element through the link to the shovel.

5. An instroke excavator comprising a jib, a haft member movable relatively to the said jib, a shovel movable relatively to the bait member, braking means upon the jib, mechanism for controlling the movement of the shovel including an element in extension of the hoisting cable and the said braking means whereby when the said element is braked by the braking means and the haft member is swung the shovel may be correspondingly moved while retaining its angular disposition in space and may be tilted when the said element is released by the braking means.

6. An instroke excavator according to claim 5, in which the mechanism directing the shovel comprises a quadrilateral linkage consisting of the braking means, the hatt member, the shovel and the said element.

7. An instroke excavator with mechanism for directing the shovel, including a shovel hart to which the shovel is pivoted, a hoisting cable operatively linked or coupled to the shovel at a position distant from the pivotal axis to permit the hoisting cable to be used for tipping the shovel, and a braking device which when operative restrains the shovel from tipping and causes it to remain approximately in the same angular disposition in space when the bait swings.

8. An instroke excavator comprising a jib, a shovel, a directing mechanism inclusive of a haft member pivoted to the jib and having the shovel pivoted thereon and by which the shovel is directed a hoisting cable, a shovel control member associated with, but movable independently of, the haft member, and a braking device, the said hoisting cable being connected with the control member which is linked or coupled to the shovel for the tilting of the shovel by the hoisting cable and the braking device being applied to the said control member so that when operative it retains the shovel approximately in the same angular disposition in space when the haft member swings.

HEINRICH SIEBERT.

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