US1799151A - Bit-forging machine - Google Patents

Description

P 7, 1931- c. 1. ANGSTROM' 1,799,151

BIT FORGING MACHINE Filed June 20, 1928 3 Sheets-Sheet 1 fi fl fl INVENTOR April 7, 1931. c. J. ANGSTROM 1,799,151

BIT FORGING MACHINE Filed June 20, 1928 5 Sheets-Sheet 3 Patented Apr. 7, 1931 UNITED STATES CARL: J. ANGSTROM', 0F PITTSBURGH, PENNSYLVANIA, ASSIGNOR TO THE MARTIN PATENT OFFICE Q HARDSOCG GOMPAN Y, OF PITTSBURGH, PENNSYLVANIA, A CORPORATION OF PENN- SYLVAN IA Application filed June 20,

This invention relates toinetal forging, and more particularly to the forging of cutter bits such as for instance, as the bits used in mining machines. 7 i r The present invention has for its object to provide abit forging machine of an improved construction and capable of substantially continuous operation.

The invention may be readily understood by reference to the accompanying drawings, in which Figure 1 is a top plan embodying my invention;

Figure 2 is a transverse vertical section in the planeof line IIII of Figure 1;

Figure 3 is a detail view of a ratchet mechanism for driving the multiple die forging isk;

Figure 4 is a vertical section through the forging disk at right angles to its axis;

' Figure 5 is atransverse vertical section through the forging disk in the plane of line VV of Figure 4;;

Figure 6 is a detail elevation of oneof the shaping rollers'of the machine; and Figure 7 is a perspective view showing one of the cutter bits adapted to be forged in the machine. 7

In the drawings which show a preferred embodiment of the machine, 2 designates the machine frame. Mounted on the frame is view of a machine a driving motor 3. The motor 3 has a gear 4 on its shaft, and this gear meshes with a gear 5 of larger diameter mounted on the shaft 6. The shaft 6 is continuously 'driven by the motor. On one end of theshaft '6 is a pinion 7 which mesheswith a gear wheel 8 on a second shaft 9 parallel to the shaft 6. The shaft 9 is continuously driven by the motor 3 through the train of gears and thespeed is reduced through the gear ratios.

Carried in bearings 10 on the frame of the machine is a heavy shaft 11 which is parallel with the shaft 9 and on which is a Wheel or disk 12. V

The disk 12 has a dove-tailed slot 13 in the periphery thereof. At intervals around the periphery of the disk, the disk is cut awav across its entire width, providing a series of shoulders 14. 'Set against the shoulders 14,

die blocks and four BIT-FORGING MACHINE 1928. Serial No. 286,864.

as best shown in Figure 4, are transverse blocks 15. These blocks provide stop elements for die blocks 16 and die block holders 17. The die block holders 1'? are of the cross section best shown in Figure 5, having a bottom plate portion 1? and an under-cut flange 17 The die block 16 has an upstanding die portion 16 projecting beyond the periphery of thedisk 12 and a flared or dove-tailed base portion 16 received in the slot 13 and resting on the base portion'17 of the holder 17. i

As best shown in Figure 5 the die block is clamped in place by reason of the fact that one side of the slot 13overhangs one side of the base 16 and the overhanging portion 17 b of the holder 17 fits over the other side of the base portion 16". A set screw 18 is provided in one sideof the disk for holding the clamping member 17 in binding relation with the die block. The die block has one end butting against the cross piece 15, as shown in Figure 4. Forwardly of each die block with reference to the direction of rotation of the disk. the disk is cut away to form a pocket 19 in which a holder 20 is retained by nates a length of cutter stock, and B designates a completed bit.

The die blocks 16 can be removed bv loosening the set screws 18 and slipping the blocks forwardly with reference to the direction of rotation of the disk afterthe holder'20 has been removed from the pocket 19. With this arrangement the die blocks can be conveniently replaced or repaired when necessary.

I In the arrangement shown, there are four sockets 22. In the preferred embodiment of the invention the disk 12 is rotated in a step by step fashion, being moved 90 'at each successive operation. For effecting this step by step'rotation of the disk a ratchet wheel 23 is secured on one end of the shaft '11. This ratchet wheel has four teeth thereon.

Loosely mounted on the shaft 11 is a bifurcated lever 24:, one arm of which is located at each side of the ratchet 23. On the lever 24 is a pawl 25 having an actuating spring 26 which is adapted to engage the ratchet teeth upon movement of the lever in the opposite direction. The lever 24 is actuated by means of a connecting rod 27 having one end thereof pivotally secured to the lever 24 at 28 and having its other end secured to the crank pin 29 on the face of the gear wheel 8. \Vith this arrangement the ratchet wheel 23 is advancing through an arc of 90 with each rotation of the gear wheel 8.

Supported on the frame 2 over the disk 12 is a lever 30 having a grooved forging roller 31, such as shown in Figure 6 at one end thereof. This roller has a groove 32 therein, which groove has a cross sectional shape substantially similar to the cross sectional shape of the die blocks 16. The roller 31 is adapted to ride on or close to the periphery of the disk and is retained in the desired position by means of oppositely arranged set screws 33 and 34 on the other end of the lever 30, these set screws cooperating with a bridge element 2 on the frame 2. One of the set screws 33 holds the end of the lever from lifting away from the bridge 2 while the other set screw limits the movement of the end of the lever toward the bridge.

Pivotally mounted in the frame under the lever 30 is a second lever 35 which is in the shape of a bell crank having two arms 35 and 35". This lever is pivotally supported on a shaft 36. At the end of the arm 35 is i i a forging roller 37 similar to the roller 31.

On the shaft 36 and extending. under the arm 35 of the lever 35 is a lever 38 having a roller 39 at its free end. On the arm 35" are set screws 40 and 41 similar in function to the set screws 33 and 34, except, however, that these set screws instead of cooperating with a fixed bridge on the frame of the machine, cooperate with the lever 38.

Parallel with the shaft 9 and located in a plane almost directly over the shaft 9 is still another shaft 42. On the shaft 42 is a sprocket wheel 43. On the shaft 11 is a sprocket wheel 44. A chain passes around the sprocket wheels 43 and 44 and serves to rotate the shaft 42 intermittently with the shaft 11. The ratio of the sprocket Wheels 43 and 44 is such, however, that the shaft 42 is rotated a complete revolution with each quarter revolution of the shaft 11. Carried on the shaft 42 is a cam 46 having a single high spot 46".

Ihe high spot on the cam is so located with reference to the disk 12 that the cam will engage the roller 39 to lift the lever 38 just as the partially formed cutter bit comes into engagement therewith and is arranged to relieve the pressure on the roller 39 just as the completed cutter bit moves out of engagement with the roller 37, as hereinafter more fully described.

In the operation of the machine an operator standing at the end of the machine drops a length of metal A into each socket 22 as the disk 12 is rotated. In the particular machine shown the stock or length of tool steel A moves through the first 90 without any operation being performed thereon. The stock is then in the position shown in Figure 4. With the next 90 movement of the disk 12 the st7ock is carried under both the rollers 31 and P) In passing under the first roller 31 the metal, which is preferably hot, is forced over the die block 16 and shaped by the groove 32. and made roughly to the shape of the finished bit. However, due to the fact that the metal is being moved through an are under the roller 31, the top of the bit is rounded instead of being flat in a longitudinal direction. By reference to Figure 7 it will be seen that it is desirable that the edge B of the cutter bit B be a straight line. In passing under the second roller 37 the metal is forged further to produce a straight edge instead of a rounded edge. This is accomplished by gradually depressing the roller 37 through the cam 46 from the beginning of the point of contact of the partly forged cutter with the roller 37 to the point where the highest part of the bit is under the roller. After the highest part of the bit has passed under the roller the highest part of the cam 46 is passed out of engagement with the cam follower 39 and the roller 37 will engage the bit with gradually decreasing pressure. By thus initially increasing the pressure from the beginning to the high point of the bit and then decreasing the pressure from the high point to the end of the bit, a straight edge is forged on the cutter notwithstanding the fact that the cutter is traveling through an arc.

As the forging disk 12 continues to rotate the completed bits can drop out into a basket or other collecting means located beneath the disk 12.

lVith this arrangement the machine can operate continuously. By means of the set screws 33 and 34 and 40 and 41, the pressure of the rolls 31 and 37 can be conveniently adjusted.

By reason of the fact that the disk 12 is rotated intermittently the operator is given sufficient time to insert the lengths of metal from which cutter bits are formed into the holding sockets. This can be done more conveniently than if the disk 12 were a continuously rotating disk.

While I have described a preferred e1nbodiment of my invention, it will be understood that the invention is not limited to the particular construction and arrangement shown but may be otherwise embodied.

I claim:

1. In a machine for the manufacture of cutter bits, a carrier disk having a bit receiving socket therein and having a die block thereon adjacent the socket, means for rotat ing the carrier, a forging roller adapted to cooperate with the die block on the carrier, and a second forging roller following the first, and means for moving the second roller toward the carrier during a portion of the rotation of the carrier and for moving the second roller away from the carrier during the next succeeding portion of the travel of the carrier by means of which a bit forged in the machine will have a straight edge.

2. In a cutter bit forging machine, a rotatable carrier, means for rotating the carrier,

. said carrier having a die surface on the periphery thereof and having a stock receiving socket adjacent the die, a forging roller cooperating with the carrier and adapted to move toward and away from the carrier, and

means for effecting the movement of the forging roller toward and away from the carrier in synchronism with the passage of the socket in the carrier past the roller.

3. In a cutter bit forging machine, a rotatable carrier, means for rotating the carrier, said carrier having a die surface on the periphery thereof and having a stock receiving socket adjacent the die, a forging roller cooperating with the carrier and adapted to move toward and away from the carrier, means for effecting the movement of the forging rollertoward and away from the carrier in synchronism with the passage of the socket in the carrier past the roller, and a second roller adjustably fixed with respect to the carrier located in advance of the first, said second named roller being adapted to roughly forge the article to shape, said first named roller being adapted toform a substantially straight edge on the cutter bit.

4. A machine for forging cutter bits comprising a rotatable carrier having a plurality of stock receiving sockets therein with die blocks on the periphery thereof adjacent each socket, means for rotating the carrier, a forging roller located at one point about the periphery of the carrier for cooperation with the die blocks thereon, and automatic means for varying the position of the forging roller disk having .a plurality of stock receiving applying increased pressure to said second roller during the initial movement of each socket and thereunder, and adjusting means for varying the pressure of each forging roll.

7. In a cutter bit forging machine, a continuous carrier having a plurality of sockets therein with a forging die adjacent each socket, a plurality of forging rollers cooperating with the carrier and past which the carrier is advanced to successively move the sockets therebeneath, and means for applying increased pressure to one of said forging rollers during a portion of the travel of each socket therepast.

8. In a cutter bit forging machine, a continuous carrier having a plurality of sockets therein with a forging die adjacent each socket, said sockets being provided for the purpose of holding pieces of stock to be forged, means for intermittently rotating the carrier, a forging roll cooperatively disposed with reference to the periphery of the carrier and adapted to cooperate with the dies on the carrier for shaping the stock, said forging roller being movable toward and away from the stock, and means for synchronizing the movement of the forging roller with the movement of'the carrier.

In testimony whereof I have hereunto set my hand.

CARL J. ANGSTROM.

with respect to the disk to apply a variable 7 pressure to each piece of stock as it engages the roller.

5. In a machine for forging bits, a carrier disk having a plurality of stock receiving sockets in the periphery thereof and having forging dies located adjacent each socket, means for intermittently rotating the carrier disk, a forging roll located at a point about the periphery of the disk for cooperation with the die blocks thereon and beneath which the die blocks are successively moved,

a second roll following the first, and means for applying increased pressure to said second roller during the initial movement of each socket and thereunder.

6. In a machine for forging bits, a carrier

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