US669258A

US669258A - Harrow-tooth.

Info

Publication number: US669258A
Application number: US1955900A
Authority: US
Inventors: John Lanz
Original assignee: Individual
Current assignee: Individual
Priority date: 1900-06-08
Filing date: 1900-06-08
Publication date: 1901-03-05
Anticipated expiration: 1918-03-05

Description

No. 669,258. Patent 6d Mar. 5, I90l.

.1. LANZ.

'I-IABRDW TOOTH.

(Application filed June 8, 1900.)

(Nb Iodal.)

WITNESSES:

N TOFI Z TOFINEYS.

UNITED STATES PATENT Qrricn.

JOHN LANZ, OF PITTSBURG, PENNSYLVANIA.

HARROW-TOOTH.

SPECIFICATION forming part Of Letters Patent No. 669,258, dated March 5, 1901.

Application filed June 8, 1900. Serial No. 19.559. (No model.)

To all whom it may concern.-

Beit known that I, JOHN LANZ, a resident of Pittsburg, in the county of Allegheny and State of Pennsylvania, have invented a new and useful Improvement in Harrow-Teeth; and I do hereby declare the following to be a full, clear, and exact description thereof.

My invention relates to an improved harrow-tooth; and its object is to provide aharrow-tooth which can be made much more cheaply and expeditiously than the present forms of barrow-teeth. The present form of common barrow-tooth comprises a bar rectangular in cross-section, with a forged point at one end and an upset enlargement or head at the opposite end. In making these harrow-teeth the bars are usually cut into sections and heated and one end thereof pointed in suitable dies and the opposite end upset to form the head. It has been proposed to form these teeth by passing a hot bar through suitable die-rollers, which partially sever the bar and form depressions in the sides thereof to give the blanks a chisel or wedge point. The blanks are then sheared off and the wedge-point is forged in suitable dies to form a pyramidal point and the opposite end is upset to form the head. Both of these processes, however, are slow and tedious and necessitate several operations with reheatings of the blanks and powerful forging machinery, thereby greatly adding to the cost of the product.

The object of my invention is to avoid the defects in the old processes of forming harrow-teeth; and to this end it consists in taking a cold or heated bar, either rectangular or triangular in cross-section, shearing the same on a diagonal line, so as to leave a pyramidal point, and shaping the opposite end to form a head, the process consisting, essentially, in

shearing and shaping the metal, no forging, strictly speaking, being necessary.

To enable others skilled in the art to make and practice my invention, I will describe the same more fully, referring to the accompanying drawings, in which Figure 1 is a perspective view of a triangular bar, showing by dotted lines how the same is out into the proper blanks. Fig. 2 is a similar view of a rectangular bar. Fig. 3 is a perspective view showing diagrammatically the shearing-dies for cutting the bar. Figs. 4 and 5 are vertical sectional views of the dies for centering the point and forming the head of the barrow-tooth, the said figures showing the dies in different positions; and Fig. 6 is a perspective view of a harrowtooth formed from a triangular bar.

As shown in Fig. 1 of the drawings, I take a bar 1, triangular in cross-section, and shear it on diagonal lines 2 2, thereby forming the pyramidal point 3 on one end of the blank and the flat or chisel point 4 on the opposite end thereof, (which is the complement of the pyramidal point 3.) When the cross-section of the bar is a regular or nearly regular triangle, the shearing is preferably done by means of shearing-dies, such as illustrated in Fig. 3. The stationary or bottom die 5 is provided with the horizontal ledge 6, on which rests the lower flat side of the triangular bar 1, and with the face 7, said face being inclined to fit the inclined side face of the triangular bar 1. The movable die 8 is provided with a horizontal ledge 9, which is adapted to pass under the lower flat side of the bar supported upon the horizontal ledge 6 of the die 5, and is also provided with the face 10, which, as shown, is inclined in a manner similar to the face 7 of the die 5 to fit the inclined side face of the triangular bar 1.- The die 8 moves in the direction of the arrow indicated in Fig. 3, passing over the die 5, the configuration of the working faces of the dies being such that the bar is held [irmly at all points while it is being sheared off. To further support the bar while being sheared, suitable stationary supports (not shown) are provided, upon which rests the lower flat side of the triangular bar. In the particular instance shown the ledges 6 and 9 are flat, as are also the inclined faces 7 and 10; but if the bar is rectangular or of irregular triangular cross-section instead of equilaterally triangular the form of the ledges 6 and 9 and the faces 7 and 10 will be modified accord ingly, andif abarof very flat triangular crosssection is used ordinary shearing-dies can be employed. Fig. 2 shows the manner of cutting a rectangular bar diagonally, so as to get a pyramidal point 12, as distinguished from a chisel or wedge point. It will be observed that in shearing diagonally a bar either triangular or rectangular in cross-section it is formed into blanks having at least one pyramidal point, while the opposite end is the complement of said point and is either chisel shape or pyramidal.

After the bar is sheared in the manner above described the blank is placed in the groove 13 of the die 14, said groove being V-shaped throughout its length and of the same depth from the point 15 to the point 16, from which latter point it gradually diminishes in depth to the end of the die, as at 17, where it vanishes. To facilitate the making of the die 14, it is formed in two

sections

18 and 19, the section 19 having the V-groove of graduallydiminishing depth. The

sections

18 and 19, however, are firmly united together, so as to form substantially one solid die. They may, if desired, be made in a single piece. The die 14 is preferably circular and has a series of V-grooves 13 cut in its outer surface and is mounted so as to have an intermittent rotary movement, so that a blank may be placed in one of the V-grooves and moved under the reciprocating die 20 and after being formed may be discharged from the V-groove on the opposite side of the reciprocating die. On the outer side of the section 19 of the lower die is secured a plate 21, which forms, in effect, an end wall of said die. The movable die 20 reciprocates in a vertical direction and has its lower face formed fiat for the greater portion of its length, as at 22, and the outer end being downwardly inclined, as at 23. The die 20 is reciprocated by any convenient mechanism. (Not shown.) In front of the die 20 is a reciprocating die 25, having its lower end shaped to form the concave surface 26 and the convex surface 27, said surfaces running into each other. After the die 20 has pressed the blank into the groove 13 and while it holds it firmly therein the die 25 moves downward and bends the end of the blank 1 down into the position shown in Fig. 4. The die 25 then recedes; but the die 20 still remains down, holding the blank firmly in the groove of the die 14. In this position the heading-die 28 moves in the direction of the arrow, Fig. 5, and its concave face 29 engages the end of the blank and curls it upward and inward to form the head 30, as shown in Fig. 5.

The operation of these dies is as follows: The blank is placed in one of the V-grooves of the die 14, and said die is then moved so that the blank is beneath the die 20, the blank being in the position shown in dotted lines, Fig. 4. The

dies

20 and 25 then move downward, the die 20 pressing the blank down in the V-groove in the die 14:, bending it at the point 31 and effectually centering the point of the barrow-tooth, and the die 25 bending the projecting end of the blank downward into the position shown in Fig. 4. The die 25 then recedes and the heading-die 28 moves forward, its concave face engaging the end of the blank, forcing said end upward and inward as shown. This operation forms a harrowtooth having a body triangular in cross-section, its point perfectly centered with reference to the body, its head neat in appearance, and is also centered. Furthermore, the curled-over head forms an eye on the end of the tooth, which serves as a means for stringing said tooth on a wire or other suitable means, so that a number of teeth can be readily attached together in a convenient bundle for shipment or handling.

In some instances it may be desirable to bend the bar 1 before shearing the same, and in that case if sheared diagonally at the point of bend the point will be sufficiently centered, and no further centering is necessary. If a bar rectangular in cross-section be used, it

willbe sheared upon diagonal lines, as indicated in Fig. 2, so as to form a blank having a pyramidal point at both ends, which is thereafter centered to form the point of the harrowtooth, and the other end is curled over to form the head. Such a blank, however, does not form a barrow-tooth that is perfectly symmetrical, and therefore I prefer to use a bar triangular in cross-section. If it is not desired to have the head of the tooth centered with reference to the body, the blank may be forced endwise into a suitable die or matrix by an ordinary reciprocating plunger or press, which will cause the point to be centered with reference to the body'and will curl over the other end to form the head.

It will thus be seen that my harrow-tooth can be made from triangular or rectangular bars by ordinary shearing and bending processes, and as no rolling, reheating, and forging operations are necessary the teeth can be made very rapidly and at but a slight cost above the price of the bars.

What I claim, and desire to secure by Letters Patent, is

1. A barrow-tooth comprising a body angular in cross-section having at one end a pyramidal point, and a bent-over portion at the opposite end to form a head.

2. A barrow-tooth comprising a body an gular in cross-section having at one end a pyramidal point which is triangular in crosssection and its opposite end being provided with an eye. p

3. A barrow-tooth comprising a triangular body having a sharp point at one end and a curled-over portion at the opposite end forming a head and an eye at that end.

4:. A barrow-tooth comprising a triangular bodyhavinga sharp point at one end centered ramidal point, and a portion at the opposite [0 with relation to the body and a curled-over end which is the complement of the point portion at the opposite end to form a head. formed into a head.

5. A barrow-tooth comprising a triangular In testimony whereof I, the said JOHN LANZ, body having a sharp point at one end and a I have hereunto set my hand.

curled-over flattened portion at its opposite JOHN LANZi end to form a head. Witnesses:

6. A barrow-tooth comprising a body an- F. W. WINTER,

gnlar in cross-section having at one end a py- ROBERT C. TOTTEN.