US1548309A

US1548309A - Bucket for placer dredges

Info

Publication number: US1548309A
Application number: US587052A
Authority: US
Inventors: William J Hall
Original assignee: American Manganese Steel Co
Current assignee: American Manganese Steel Co
Priority date: 1922-09-09
Filing date: 1922-09-09
Publication date: 1925-08-04
Anticipated expiration: 1942-08-04

Description

-Aug. 4, 1925.

W. J. HALL BUCKET FOR PLACER DREDGES Filed Sept. 9, 1922 4 Sheets-Sheet l a H W 4 1925. fiw

W. J. HALL.

BUCKET FOR PLACER DREDGES Filed Sept. 9, 1922 4 Sheets-Sheet 2 Aug. 4, 1925.

3,48 3% W. J. HALL BUCKET FOR PLACER DREDGES Filed Sept. 9, 1922 4 Sheets-Sheet 3 Patented Aug. 4, 1925.

UNITED STATES 1,548,309 PATENT I OFFICE.

WILLIAM J. HALL, or 'oHIoAGo'HEIGfiTs, rLLINo-Is, GANESE STEEL COMPANY, or CHICAGO, ILLINOIS,

ASSIGNOR TO AMERICAN MAN- A CORPORATION OF MAINE.

BUCKET FOR PLACER DREDGES.

Application'filed September 9, 1922. Serial No. 587,052.

T 0 all whom. it may, concern:

Be it known that I, IVILLIAM J. HALL, a citizen of the United States, residing at Chicago Heights, in the county of Cook and State of Illinois, have invented certain new construction of dredge bucket, the main body of which can be produced by casting, and can be successfully and completely heat treated to properly condition the metal of which it is formed. The invention finds special application to dredge buckets of the kind which are operated in an endless chain,

and particularly to those of large capacity and heavy massive construction.

In order that buckets of this type may withstand the severe shocks and wear to.

which they are subjected in use, special alloy steel, such as manganese steel, is extensively used in their production. But the great variation in thickness of metal forming different portions of these buckets gives rise to many foundry problems, particularly when manganese steel is employed in pro ducing them. One of the characteristics of manganese steel is its high coefficient of expansion, amounting to as much as f ths of an inch per foot. between the temperature at which the metal is poured and the cold state, and this shrinkage has to be taken into consideration in order to avoid cracks and'mternal stresses that would be detrimental to the casting.

Again, in the normal cast state, manganese steel is very brittle, being a compound of austlnite (a solution of non manganese and the carbide of iron and manganese) and free cementite (composed of the carbides of iron and manganese which remain undissolved). But since heating of the cast metal to proper temperature decomposesthe ce-.

mentite and renders the whole structure austinitic, which lattercondition can be retained by plunging thecasting into cold water, and which condition produces a unique metal which is ductile, highly resistant to wear and of great strength, the practice has grown up of heat treating manganese steel castings. And here again the inequality in thickness of the various parts of a cast metal dredge bucket entersin to complicate the problem of production.

Cast manganese steel-can ordinarily be successfullyheat treated up' to sections of about four inches in thickness. Moreover, a

light section properly heat treated is much stronger and ofbetter shock resisting qual- 1ty than a heavy section improperly treated.

But it is not always practicable to reduce I sections of manganese steel castings in cer.

ta in d1rections sufficiently to bring them within the temperingrange, owing to the necessity of maintaining high orders of strength in such directions, and a serious problem isoften presented in the design of' proper sections. This is particularly true with respect to the knuckles and eyes which constitute the hinging connections on dredge buckets where, in addition to opening up the metal to insure heat treatment, volume of metal must be maintained in. certain directions sufficient to insure very high load car rying capacity. In practice, a single bucket of this type may embody upwards of a ton of metal in its structure, and may enter into an endless chain of such buckets, developing -tensional strains upon their connecting knuckles and eyes amounting to many-tons, so thatereduotion in the section of such connections'in the direction of loading is out of thequestion.

The present invention provides a construc t-ion of dredge bucket which can be successfully produced from manganese steel by,

casting and subsequent heat treatment, and the invention consists in the construction hereinafter described, whereby ample resistance to shocks, stresses, and erosion lmposedupon the bucket in use, is insured, and the portions of the structure which ordinarily present thicknesses in excess of those which can be successfully heat treated, are opened up or interiorly exposed to heat conduction essential to uniform heating'and 0001- In the accompanying drawings- Figures 1 and 2 are, respectively, a Vertical central longitudinal section and a horizontal section of one form of dredge bucket embodying the subject-matter of the invention; the section of Figure 2 being in a plane indicated by the line'2 X of Figure 1.

Figure 3 is a front elevation of one of the two symmetrically formed sides of the bucket.

Figures 4, 5, and 6 are detailed sections taken, respectively, in planes indicated by the lines 45-4", B -*5 and 6"6 of Figure 1.

Figures 7 and 8 are, respectively,a side elevation and a horizontal section of another design of bucket in which the features of the invention are embodied; the section of Figure 8 being in a plane indicated by the line 8"-8. of Figure 7.

Figure 9 is a front elevation of one of the two symmetrically formed sides of the hinging knuckle 4 (Figs. 1 and 2) or 4* (Figs. 7 and 8) transversely disposed across its rear end, and hinging eyes 5 (Figs. 1 and 2) or 5 (Figures 7 and 8) spaced apart at its front end in position to receive between them the hinging knuckle 4 or P to which they are pivotally connected by pintles passing through bores 6, 7, (Figs. 1 and ,2) or 6, 7 (Figs. 7 and 8). It is also customary to provide dredge buckets of this kind with bottom shoes 8 (Figs.

' 1 and 2) 0r8 (Figs. 7 and 8) upon which they are supported in traversing their bridge or track, and passing around the sprockets or tumblers at the end thereof.

But these knuckles, eyes, and shoes,'in order to develop resistance to destructive forces encountered 1n use, requlre to be made w th i dimensions in excess of that whichcan be successfully heat treated in manganese steel.

Thepresent invention admits oftheuse of dimensions for I the before-mentioned parts in the directions in which the destructive forces are imposed upon them in use, but opensup' these parts in a manner to afford access of heat to and from the interior thereof in heat treating and quenching or cooling. J

According to nels 9 running in planes parallel to the direction of draft transmitted throughthe hinging, connection, and leaving, in positions alternating with said channels, an-

Figures 1 and 2, the knuckle 4 is provided with a series of external channular strengthening sectors 10. According to Figures 7 and 8, the channels 9 are of more uniform depth throughout the semicircumference of the approximately cylindrical hinging knuckle, thereby leaving annular stren hening sectors 10 of greater mass thant e sectors 10 of Figures 1 and 2, which increased dimension will be desirable where the bucket is constructed with great capacity. By means of the

channels

9 or 9", considerable areas of the wall of the pintle bore are reduced to a transverse dimension which permits absorption and giving ofi of the heat entirely through the metal section, while the depth of the channels is such as to expose

lateral faces

10 or 10 upon the strengthening

sectors

10 and 10, thereby avoiding exclusion of heat from parts radially within said sectors. In this way, a massive, substantially durable, and properly heat-treated hinging knuckle is developed on the bucket.

In order to insure proper heat-treatment formed therein which serve similarly to shoes or bottom may extendin any other desired direction with similar results.

An important advantage in using the channels in the bottoms or shoes is that they resist the peening action or flow of metal on the bottom of the bucket, due to pounding which the bucket receives in passing over rollers upon its bridge'or around the sprockets or tumblers at thev ends of the bridge.

In order to 5* in a manner to render them subject to thorou h heat treatment without detracting from tie strength-whichthey are required to possess in use, these eyes are recessed or opened up in one or another of several Ways, two of which are herein shown by way of illustration.

According to the construction shown in Fi vi ed with slots 12 extendin through the vertical and longitudinal imensions of said-eyes, except for an annular sector 13 left 'at the front of the eye in position to render continuous the draft bearing of the form the hinging eyes 5 or x res '1, 2, 3, and 6, the'eyes 5 are prohingingopintle throughout the transverse dimension of the eye; lugs 14, projecting vided with a rearwardly extending slot 17 which further opens u this portionof the metal; The result of t is'construction is a complete cylindrical wall defining the-pintle bearing 6 to the extent of the thickness of the wall 15, and a bearing for said pintle limited to the front sector 13 in the outer wall 16 of the eye.

According to Figures 7 and 8, the eye is provided with an exterior approximately semi-annular groove 18 which leaves intact a. semi-cylindrical front bearing for. the pintle, and the entire lug of the eye member in rear of said semi-cylindrical bearing is slotted through from side to side, as shown at 19. Here, the elongated lugs 20 are pr vided (see also F lgures 12 and 13) for the purpose of distributing heat to and from the adj acent parts, and positioning a filler block or other inserted piece, employed for completing the bearing.

To further open up the slide shoes, and

particularly in view of their relation to the v inclined'bottom 3, to which they extend in H1 angular direction, these slide shoes may be.

provided with

lateral recesses

21, 21, 22, 22 between them and the bottom 3,'which leave the slide shoes of reduced section. I I claim:

1. A cast metal dredge bucket formed at bottom with slide shoes and having channels intersecting said slide shoes, reducing the thickness of the metal thereof, and opening up said metal to the absorption and giving off of heat in heat treatment of the casting.

, 2. cast metal dredge bucket constructed with an integral hinge knuckle near its bottom, and with slide shoes upon its bottom adjacent to said knuckle; said knucklebeing provided with a transverse bore to receive a pintle and having in the Wall of saidbore external channels leaving strengthening ribs alternating with reduced wall sectors; and said channelsextending alon the slide shoes.

3. A cast metal dredge buc et having upon its bottom slide shoes integral therewith, said slide shoes being provided with channels de; 1 veloping areas of reduced thickness alternating with surface ribs vandexposingthe sides of said ribs and metal lying inwardly from the channels to the absorption and giving ofl of'heat in the heat treatment of the casting.

cast metal dredge bucket having an .inclinedbottom and slide shoes integral with said bottom and extending at an angle thereto; sand slide shoes havingrecesses extending laterally thereinto between portions of their treads and the inclined bottom to 'open up and giving off of heat in heat treatment.

5. A cast metal dredge bucket having an integral hinging eye provided with a bore to receive a pintle, and having a slot extending inwardly from the pintle bore to open up the metal of the eye for the'absorption and giving off of heat in heat treatment of the casting.

6. A cast metal dredge bucket having an integral hinging eye provided with a bore to receive a pintle, andhaving a slot extending inwardly from the pintle bore to open up the metal of theeye for the absorption and giving oil of heat in heat treatment of the casting; said slot lying in a vertical plane.

7.- Acast metal dredge bucket having an integral hinging eye provided with a bore to receive a pintle, and having a slot extend. inginwardly from the pintle bore to open up the metal of the eye for the absorption and giving off of heat in heat treatment of the casting; said slot lying in a vertical. plane and'extending through the eye to its forward end.. v

g 8. A cast metal dredge bucket having an integral hinging eye provided with a bore to receive a pintle, and having a slot extending inwardly from the pintle bore to open up the metal of the eye for the absorption and giving off of heat in heat treatment of the caste s;

ternal channel surrounding the front wall of its pintle bore.

9. A cast metal dredge bucket having an integral hinging eye provided with a bore to receive a pintle, and having a slot extend,

ing inwardly from the pintle bore to open up the metal of the eye for the absorption and giving off of heat in heat treatment of the casting; said slot lying in a horizontal plane; said eye being also provided with an external channel surrounding the front wall of its pintle bore; and said channel extending inwardly and merging with said slot.

10. A cast metal dredge bucket having an integral hinging eye provided with a bore to receive a pintle, and having va slot extending inwardly from the pmtle bore to open upthe metal of the eyefor the absorp tion and giving ofi of'he'at 1n heat treatment of the casting; said slot lying in a vertical plane; and the Walls of said slot being prosaid slot lying in a horizontal planef and said eye being also provided with an ex.-