USRE21405E - Power shovel - Google Patents

Description

March 19, 1940. c, E, STI HL Re. 21,405

POWER SHOVEL Orizinal Filed Sept. 18, 1937 I5 Sheets-Sheet l INVENT OR.

AHORNEYIS C. E. STIEHL POWER SHOVEL March 19, 1940.

3 Sheets-Sheen Original Filed Sept. 18, 1937 INVENTOR.

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ATTORNEYS,

C. E. STIEHL POWER SHOVEL Much 19, 1940.

Original Filed Sept. 18, 1937 3 Sheets-Sheet 5 r m m 5i. n r I f u r 2 t u I I L- Ca M QYZZEZL INVENTOR.

d B Wow- ATTORNEYS.

Reiuued Mar. 19, 1940 )1 UNITED STATES PATENT OFFICE POWER SHOVEL Original No. 2,140,460 dated December 13, 1938,

Serial No. 164,454, September 18, 1937.

November 3, 1939, Serlalplication for reissue No. 302,727

8 Claims.

My invention relates to new and useful improvements in power shovels, and more particularly power shovels of the type having a boom and an outward digging dipper mounted on the end of a handle, which handle is reciprocable with respect to a point on the boom known as the shipper shaft, the dipper being movable in a circular are about this point as a center.

The saddle block is that portion of the assembly which holds the dipper handle to the shipper shaft, and through which the dipper handle reciprocates.

The dipper in digging encounters two sorts of stresses which have thus far presented almost insuperable problems in shovel design. The first of these is an uneven downward pressure of the bank upon the twofront corners of the dipper. The second of these is a sideward push upon the dipper; this latter occurs not only during digging, but also during acceleration and deceleration of the swinging cycle; this sideward push will be referred to as side-thrust."

If the handle be built narrow, to pass through a divided boom, a side thrust on the dipper is apt to tear the boom apart. If, on the other hand, the handle be built in two parts, straddling the boom, its side thrusts and twists would impart a twist to the boom. To meet these objections,

various expedients have been adopted in the past,

such as building the boom with a spring foot, and/or widely supporting the boom at its outer point and at the shipper shaft, either with or without some interlock between these two support means. But none of these expedlents has been wholly satisfactory.

Accordingly it is the principal object of my present invention to provide a novel form of construction of the front and equipment of a power shovel, so that the digging strains will be transmitted to those parts of the machine best able to stand them, and be resisted at such points.

A further object of my present invention is to provide a dipper handle and a resilient saddle block mounting therefor, so contrived and designed as to form one of the elements of my main combination.

In addition to this principal object, I have worked out a number of novel and useful details, which will become readily evident as the description progresses.

My invention is deslgned to combine all of the advantages with none of the disadvantages of the expedients of the prior art.

To accomplish this end, I combine four features, namely: (1) a freely swivelabl'e dipperthe saddle-block, moreover, tends to restore the handle to the plane of the boom. The rope thrust eliminates uneven presentation of the handle to its crowding means, which uneven presentation would otherwise largely offset the advantages gained by the just-mentioned flexibility. And the twin hoist-ropes serve'to steady the handle against twisting, and yet do not impart any twisting strain to the boom.

A fairly satisfactory subcombination would consist in items 1,3 and 4, with item 2 as a very desirable addition.

Another fairly satisfactory sub-combination would consist in items 1, 2 and '4, with item 3 as a very desirable addition.

Also I wish to claim specifically the details of item 2. I

My invention consists in the novel parts, andin the combinations and arrangements thereof, which are defined in the appended claims, and of which one embodiment is exemplified in the accompanying drawings, which are hereinafter particularly described and explained.

Throughout the description, the same reference number is applied to the same member or to similar members.

Figure 1 is a side elevation of a power shovel embodying my invention.

Figure 2 is a plan viewof the boom, handle and ropes of my invention, taken along the line 2-2 of Figure 1.

Figure 3 is a plan view, partly in section, of the saddle block and part of the boom andhandle of Figures 1 and '2, taken along the line 3-3 of Figure 4.

Figure 4 is a side elevation of these parts, taken the propelling base of a power shovel, on which is mounted the revolving irame l2. This latter carries a boom hoist winch II, a dipper hoist winch i4, and a dipper thrusting winch ll.

Winch I3 manipulates the widely spaced boom suspension cables Ii. Winch ll manipulates twin hoist ropes l'l. Each of these ropes passes over one of four boom point sheaves ll, around one of a pair of widely spaced sheaves attached to the dipper l9, and back over one (preierably another) of the sheaves II to the winch. This doubles and equalizes each rope.

The dipper I9 is carried on the outer end of'a tubular handle 2|, which slides in the saddle block, to be hereinafter described, mounted on the boom 2|. Winch l5 manipulates thrust rope 22, attached to the rear end of handle 2|, and retracting rope 23, attached to the front end 01' handle 20.

As already stated, the use of this means of thrusting and retracting permits the handle to swivel in the saddle block, without introducing any problems of proper interaction oi the thrusting parts on the boom with the thrusted parts on the handle.

Turning now to Figures 3 to 5. we see that the above-mentioned saddle block consists of a hollow member 24, of rectangular cross-section, the bottom 01' which is appropriately slotted to receive roller 25, which revolves about shipper shaft 26. The top and bottom of member 24 each terminates in two headed yokes 21, making four such yokes in all. The sides of member 2| depend to form bearings 28, to support the member on the shipper shaft 26.

The shipper shaft 26 is in turn supported from boom 2| by brackets 29.

Each pair of yokes 21 supports, by means of bolts 3. and springs ll, two curved pieces 32, each oi which carries a bearing plate It, to bear against the sides of the handle 2..

Ropes 22 and 23 pass over sheaves 34, carried by the shipper shait 26.

Turning now to Figures 6 and '1, we see how, when a side thrust is imparted to the dipper, and thereby the handle 20 is thrown sidewardly, the resiliency oi the saddle block permits this movement, without imparting undue strains to the saddle block assembly, and thence to the boom.

0! course it is to be understood that, from the viewpoint of my broad general combination, other forms of resilient saddle block might be used, and even a non-cylindrical handle, provided that it is permitted in some way to swivel, as by having it reciprocate in a cylindrical guide member within a saddle block similar to that described above.

Any twist on the handle 20, imparted by an uneven pressure on one or the other i'ront corner of the dipper, is, due to the cylindricality of the handle 20, borne solely by the widely spaced twin hoist-ropes ll.

Having now described and illustrated one form of my invention, I wish it to be understood that my invention is not to be limited to the specific form or arrangement of parts hereinbei'ore described, except in so far as such limitations are specified in the appended claims.

This application is a continuation-in-part, as to all common subject-matter, ofmy copendin'g application, Serial No. 78,670, filed May 8, 1936, for improvements in power shovels, which application now stands allowed under date of May 21, 1937, and which has now been permitted to'lapse without prejudice, in view 01' its supersession by this present application.

I claim: 1. In a power shovel, the combination of: a base; a boom, inclined forwardly therefrom; a hoist winch supported by the base; a thrust winch supported by the base; a handle, mounted on the boom for reciprocation, and for angular movement in a vertical plane about a flxed' point on the boom; a digging dipper carried at the outer end of the handle; means supporting the handle at the above-mentioned point for tree turning about the handle axis, while resiliently resisting side-thrust; flexible tension members, actuated by the thrust winch and directly applied to the handle, for reciprocating the handle;

twin sheaves, laterally widely spaced at the outer end of the boom; and twin flexible hoist members supporting the dipper at laterally widely spaced points, and thence passing over the twin sheaves to the hoist winch.

2. A power shovel, according to claim 1, characterized by the further fact that the handle is cylindrical.

3. In a power shove], the combination of: a base; a boom, inclined forwardly therefrom; a hoist winch supported by the base; a handle, mounted on the boom for reciprocation, and for angular movement in a vertical plane about a flxed point on the boom; a diggingdipper carried at the outer end of the handle; means supporting the handle at the flxed point for free turning about the handle axis, while resiliently resisting side-thrust; twin sheaves, laterally widely spaced at the outer end of the boom; and twin flexible hoist members supporting the dipper at laterally widely spaced points, and thence passing over the twin sheaves to the hoist winch.

4. A power shovel, according to claim 3, characterized by the further fact that the handle is cylindrical.

5. In a power shovel, the combinaion of: a base; a boom, inclined forwardly therefrom; a hoist winch supported by the base; a thrust winch supported by the base; a handle, mounted on the boom for reciprocation, and for angular movement in a vertical plane about a flxed point on the boom; a digging dipper carried at the outer end of the handle; means supporting the handle at the above-mentioned point for free turning about the handle axis; flexible tension members, actuated by the thrust winch and directly applied to the handle, for reciprocating the handle; twin sheaves, laterally widely spaced at the outer end of the boom; and twin flexible hoist members, supporting the dipper at laterally widely spaced points, and thence passing over the twin sheaves to the hoist winch.

6. A power shovel, according to claim 5, characterized by the further fact that the handle is cylindrical.

7. In a power shovel, the combination of: a base; a boom, inclined forwardly therefrom; a cylindrical handle, mounted on the boom for reciprocation, and for angular movement in a vertical plane about a fixed point on the boom; :1. digging dipper carried on the outer'end oi the handle; and a. saddle-block assembly, supporting the handle at the above-mentioned point, and made up of the following parts: a shipper shaft, carried by the boom; a handle-supporting roller, journaled on the shipper shaft; a hollow saddle block member, materially larger in cross-section than the cross-section of the handle; a pair of curved handle guides, laterally spaced at each end of the hollow member; and laterally yieldable resilient means whereby the member supports these guides.

8. In a power shove], the combination of: a base; a boom, inclined forwardly therefrom; a. handle, mounted on the boom for reciprocation, and for angular movement in a vertical plane about a fixed point on the boom; a digging dipper carried on the outer end of the handle; and a saddle-block assembly, supporting the handle at the above-mentioned point, and made up of the following parts; a shipper shaft, carried by the boom; a handle-supporting roller, journaled on the sh pper shaft; a saddle block member; a.

pair of handle guides, laterally spaced at each 5 end of the member; and laterally yieldable resilient means, whereby the member supports these guides.

CARL E. STIEHL.

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