US1776103A - Means and method for forming soft-metal bars - Google Patents

Description

Sept. 16, 1930. B. F. BURT 1,776,103

MEANS AND METHOD FOR FORMING son METAL BARS Filed Feb. 7, 1929 BSheets-Sheet 1 Sept. 16, 1930. B. FQBuRT MEANS AND METHOD FOR FORMING SOFT METAL BARS Filed Febf'l', 1929 6 Sheets- Sheet 2 Sept. 16, 1930. a. n BURT MEANS AND METHOD FOR F'QRMING SOFT IETALJBARS B. F. BURT Sept. 16, 1930.

MEANS AND METHOD FOR FORMING SOFT METAL BARS 6 Sheets-Sheet 4 Filed Feb. '7, 1929 Z9 5/ Y Z5 Z7 /4/ I07 26 28 as Sept. 16, 1930.

B. F. BURT 1,776,103 D FOR FORMING sow METAL BARS Filed Feb. 7, 1929 6- .$heets-$he,et 5 a 4 77 7 47 Sept. 16, 1930. B, R 1 776 103 MEANS AND METHOD FOR FORMING sow METAL BARS Filed Feb. 7, 1929 s Shets-$heet e 7 Gumm Patented Sept. 16, 1930 UNITED STATES BENJAMIN I. BURT, OF ROCHESTER, NEW YORK MEANS AND METHOD FOR FORMING SOFT-METAL BARS Application filed February 7, 1929. Serial No. 338,100.

My invention relates broadly to the art of extruding metal through forming dies and more particularly to extruding molten metal, such as type metal through forming dies,

wherein it is cooled or solidified, to form continuous leads, rules and the like, which are cut, as they emerge from the dies, into predetermined lengths to be used by printers.

The principal object of my invention is to provide a means and method of producing metal bars, such as printers leads, rules and the like, in large'quantities and so cheaply that printing otfices, which heretofore have been limited to the use of commercial leads and rules, may, by means of my invention, make their own of the size and form best suited to their needs, and so cheaply that the leads and rules need not be separated from the used type to be used again, but will be remelted with the type and re-cast with my machine, this being cheaper than saving the old leads.

Other objects of my invention relate to means for melting and extruding the metal,

the dies for forming leads and rules of various sizes in the same machine, means for cutting and discharging the bars from the machine, and means for adjusting and synchronizing all of the parts to form an efiicient and compact machine.

Still other objects and advantages of my invention will be apparent to those skilled in the art, as the specification proceeds, and need not be specifically pointed out.

With the above and other objects in view, reference will now be had to the accompanying drawings wherein a preferred embodiment of my invention'is illustrated.

1 is a top plan, the cover of the gear housing and the receiving table being removed to show certain of the parts beneath.

Fig. 2 is plan view, with the cylinder, dies and operating mechanism in section and part of the cover plate of the receiving table broken away to show the delivery plungers and fingers.

Fig. 3 is a side elevation of the machine.

Fig. is a longitudinal section of the cylinder and dies, the piston being near the end of its working stroke.

Fig. 5 is an enlarged plan View of one end of the machine.

- Fig. 6 is a section on the line 66 of Fig. 3.

Fig. 7 is a section through the cylinder End melting pot taken on-the line 77 of Figs. 8 and 9 show the cutoff and delivery plunger operating means in two positions.

Fig. 10 (Sheet 3) is a section substantially on the line 1010 of Fig. 6 showing the cutoff and delivery drive shaft.

Fig. 11 (Sheet 1) is a detail of the slide for operating the reversing switch.

Fig. 12 (Sheet 1) is an enlarged view of the adjustable stop for determining the stroke of the plunger, taken on the line 1212 of Fig. 11.

Fig. 13 (Sheet 1) is an enlarged view of the driving clutch, taken on line 1313 of Fig. 10 and Fig. 14c (same sheet) is a section on the line 1414 of Fig. 10.

Figs. 15, 16 and 17 are sections taken on the line 15-45, Fig. 10, showing diiferent positions of the clutch for driving the cutofi shaft in timed relation to the plunger stroke.

Figs. 18 and 19 (Sheet 3) are detail Views of the clutch finger.

Figs. 20, 21 and 22 (Sheet. 2) show twopart dies adapted to make rules and leads of different cross-section. I

F Fig. 23 is a section on the line 2323 of Fig. 24 is a detail of the trip clutch operating mechanism.

Referring to Fig. 2, the cylinder 25 is submerged in the molten metal 26 Within the reservoir or melting pot 27 the cylinder having a flange 28 at one end bearing on the head 29 while the other end of the cylinder is threaded to receive the nut 30 which bears against the other head 31 of the melting pot. Molten metal enters the cylinder through the valve 32 (Fig. 7) when the plunger or ram 33 (Fig. 2) makes its return-stroke, the valve 32 then seating because it is made of material, such as steel, that is of less specific gravity than the molten metal. On the forward or working stroke of the plunger, the molten.

metal is forced through the die or nozzle 34,

which is water jacketed so that the metal solidifies while being extruded in the form of a bar 35 on the delivery table 36. When the ram 33 reaches the end of its working stroke and starts again on its next returnstroke, a circular cut-ofl' saw 37 is raised by mechanism presently to be described and cuts off the bar 35 adjacent the die 34.

The ram 33 extends beyond the cylinder 25 and is enlarged at its rear end and screw threaded at 38 to engage a correspondingly threaded nut 39 secured to the worm wheel 40 and bearing on the thrust bearing 41 which is supported by the head 42. Tie rods43 connect the head 42 to the head 31 of the melting pot and take up the thrust on the ram 33. The worm wheel 40 is driven in one direction to advance the ram 33 and reversed to withdraw it by mechanism presently to be described,

A shaft 44, driven by a reversible electric motor or other suitable source of power, carries a worm 45 which meshes with and drives the worm wheel 40 and also with a worm wheel 46 for driving the cut-off ,and. delivery shaft 47. The worm wheel 45 and nut 39 are rotated in opposite directions by the shaft 44 to advance and withdraw the plunger 33, but

the cut-oif'shaft 47 is rotated only in one di-- rection and that intermittently and in timed relation to the plunger stroke, by clutch mechanism best shown in Figs. 10 and 13 The movements of the plunger or ram 33 are controlled by mechanism best shown in Figs. 3, 5, 6, 11 and 12. The frame of the machine that houses the driving mechanism has a top plate or cover 47 provided with a slot 48 extending parallel to the plunger and somewhat longer than its greatest working stroke. A slide 49 within this slot has a limited movement in opposite directions, and at one end has an adjustable stop 50, while its other end has a pair of lugs 51, 51, adapted to throw the reversing switch 52 in opposite directions to reverse the motor, or other means for driving the shaft 44, at each end of the plunger stroke.

A reversing yoke 53 travels with the plunger 33, sliding on the upper tie rod 43, and has a finger 54 operating in the slot of the slide 49, as best shown in Fig. 6. The finger 54 engages the slide 49 at one end, (at the end of the. outstroke of the plunger), and actuates the reversing switch 52 to reverse the motor, or tither driving means, to cause the plunger 33 to advance in the cylinder and .extrude through the dies the metal that now fills the cylinder. The adjustable stop 50 is set at such a point in the slot of the slide 49, that it will be engaged by the finger 54 and move the slide 49 to again reverse the switch 52 when the plunger or ram has moved far enough to have extruded sulficient metal to form a rule of the desired length. This causes the ram to be again retracted and the operation is repeated. The length of the ram travel is controlled byt-he position of the stop 50, and the length of the lead or rule will depend not only on the length of the stroke of the ram but also on the .cross-sectional area of the forming die. Thus with a given plunger stroke, a much longer lead will be produced with a die as shown in Fig. 21 than with the larger die shown in Fig. 20. Conversely, if leads or rules of the same length are wanted, the plunger stroke will be longer when using the dies of Fig. 20 than when using the dies of Fig. 21 or 22.

The mechanism for operating the cut-ofi Referring first to Fig. 10, the sleeve 55 fixed in the head 42 provides bearings for the worm wheel 46 and shaft 47. The wheel 46 is secured to one part 56 of a one-way ball clutch 57. See Fig. 13. When the plunger is advancing on its working stroke, this clutch is inoperative, the outer member 57 being stationary and the inner member running idly. When the drive shaft 44 is reversed to retract the plunger, the clutch 57 rotates idly on the inner sleeve 58 of a trip clutch, which is automatically controlled to drive the shaft 47 through one rotation, thereby raising the saw 37 to cut off the lead (Fig. 9) and again returning the saw to inoperative position (Fig. 8) I When the lead or rule has been cut off, the delivery plungers 59, Fig. 2, are actuated by the levers 60 to press the lead or rule to one side on the delivery table 36, out of the path of the next lead to be extruded.

The clutch 58 is of the type generally known as a punch-press clutch, and while the outer sleeve 57 (the one sleeve 57 is common to both clutches. See Fig. 10) is driven continuously during the interval that the ram is being retracted, the member 58 and shaft 47 make but one rotation and then stop.

The collar 58 is fixed to the shaft 47 and has a sleeve 61 fitting within the clutch member 57. A clutch finger 62 fits in a circular bore 63 in the collar 58, and has a semi-circular extension .64 which lies within a semicircular recess 65 formed in the sleeve 61, coaxial with the bore 63.

The collar 57 has a corresponding semi-circular recess 66, adapted to register at times with the recess 65. (See Figs. 14 to 17, Sheets 1 and 5.) When the finger 62 is in such po sition that the extension 64 lies wholly within the recess 65, the clutch runs idly, and the shaft 47 is not rotated. (See Fig. 17 But when the extension 64 lies artly within each recess 65, 66, the shaft 4 will be rotated (.Fig. 15).

The operation of this clutch will now be described. .The finger 62 as a curved lateral extension 67, (Figs. 6, 18, 19) which is urged outwardly by the spring 68, tending to cause I the upper end 'of lever 74 is released.

the semi-circular part 64 to lie within both recesses 65, 66, as in Fi 15. The collar 58 has a recess 69 within w ich the extension 67 is partly housed when depressed against the spring 68 (Fig. 6). A lower trip lever. 70, pivoted at 71, (Fig. 6) has a notch 72 in its lower end which normally engages the extension 67 and depresses it into the recess 69 so that the trip clutch is inoperative. A spring 73 tends to hold the trip lever in this position. An upper trip lever 74 also is pivoted at 71 and at its lower end has a finger 75 engaging lever 70. A spring 76 pulls on the upper end of lever 74 and is stronger than the spring 73, so that the lever 70 will be disengaged from the trip finger extension 67, whenever See Figs. 1, 3, 5 and 6.) A clutch control liever 77 is pivoted at 78 at one end and at the other end is adapted to engage the upper end of the lever 74 against the tension of the spring 76. A light spring 79 tends to pull the control lever 77 to one side to release the lever 74 (see Fig. 5), and a cam 80 on the oke 53 engages a roller 81 to press the lever 7 back into engagement with the lever 74 at the proper time.

The slide 49 carries a laterally projecting foot 82, extending into the path of the upper end of the lever 74, and is adapted, as the slide is moved to the right (Figs. 1, 3 and 5) at the end of the piston stroke, to engage the upper end of lever 74 and move it against the pull of the spring 7 6. 1

The operation of the clutch mechanism for driving the shaft 47 is as follows. When the ram 33 is being forced forwardly to extrude the metal, the clutch member 56 runs idly, the outer member 57 being stationary, so that the trip clutch 58 is inoperative regardless of the position of the levers 7 O, 74 and finger 62. As the piston nears the end of its stroke, the finger 54 engages the adjustable stop 50 and moves the slide 49 to the right, carrying the foot 82 with it into engagement with the lever 74. Just previous to the end of the forward stroke, the positions of the clutch control levers and cams are as follows. The foot 82 is to the left (Figs. 3 and 5) out of engagement with lever 74 which has been pulled to theleft by spring 76 and holds the lower end of lever 70 out of engagement with clutch finger 67. The cam 80 is out of engagement with roller 81 and control lever 77 has been pulled toward the center of the machine out of engagement with the upper end of upper trip lever 74. The

spring 68 has raised the clutch finger 67 higher than the notch 72 (Fig. 24), so that the lever cannot return to position. The plunger now reaches the end of its forward stroke carrying the foot 82 into engagement with lever 74, forcing it to the right and releasing lower trip lever 7 O, which is then drawn by the light spring 73 against clutch finger 67 ready to move into position to receive the finger in notch 72 and confine it in recess 69 scribed, and the drive shaft now being re-' versed, the clutch member 57 begins to turn, but the member 58 remains stationary until the two grooves 65, 66 register, at which time the finger 64 engages in both grooves and causes the clutch 58 and shaft 47 to rotate. A slight rotation of the clutch 58 carries the lateral extension 67 past the lever 70, and the spring 73 pulls the lever to the left to the position shown in Figs. 3 and 10, so that as the clutch continues to turn, the extension 67 will come under the lever and in the recess 72 and be depressed against the pressure of spring 68. This takes place when the clutch and shaft 47 have made one complete rotation and turns the finger again into inoperative position as shown in Fig. 17, so

that continued rotation of the clutch 56, 57'

has no effect on shaft 47. I

The ram 33 continues on its back stroke, and near the end of its stroke, the cam 80 engages roller 81 and moves lever 77 into engagement with lever 74 as shown in Fig. 5. Continued movement of the piston, causes slide 49 to be shifted to the left carrying foot 82 to the left of lever 74 and again reversing the drive shaft.

The ram now starts on another working stroke and forward movement of cam 80 releases lever 77 which is pulled to one side by spring 79. This releases upper trip lever 74 which is pulled over by spring 76 and causes lever 70 to release the finger 67 which is forced up by spring 68, but the shaft 47 is not driven because the clutch 56, 57 is inoperative during the Working stroke of the ram. However, the lever 70 and clutch finger 62, 68, remain in this position, ready to come into operation and drive the shaft 47 through one rotation as soon as the shaft 44 is reversed.

The cut-ofl and delivery mechanism that are actuated by shaft 47 will now be described.

As the rules or leads 35 leave the forming dies 34, they come out on the table 36, the stroke of the ram having been regulated by the position of the stop 50, so that the lead extruded will be of a predetermined length. When the metal has ceased to flow through the die, and the ram is being retracted, the shaft 47 is given one complete rotation, as previously described, which operates the cutoif and delivery mechanism.

As a rule 35 progresses along the table 36, by pressure of the metal behind it, it is kept in alignment with the rules previously extruded by the spring pressed retaining fingers v a lead 35 is being extruded, while in Fig. 2,

the last lead has been cut off and moved to one side by the plungers out of the path of the next lead to be extruded from the dies.

The shaft 47 has bearings in the heads 31, 29 (Figs. 3 and 10) and at its one end carries a cam 85 and crank 86. The cam 85 cooperates with a roller 87 on one end of an arm 88 which is fixed to a rock shaft 89 carrying the delivery levers 60. (Figs. 8 and 9.) These :evers actuate the plungers 59 (Figs. 2 and 4) as previously described to move the stack of leads or rules out of the path of the next following one. I

The saw 37 is secured to one end of a shaft 90 mounted in a swinging frame 91 and driven from an electric motor 92 or other source of power. The motor is eo-axial with the swinging frame 91, as best shown in Fig. 1. The motor 92 is only illustrative of a driving means, and of course any driving means, as a shaft driven from the main drive shaft 44, could be substituted.

A downwardly and forwardly extending link 93 is pivoted at one end to the swinging frame 91 and at the other end is mounted on the pin 94 of the crank 86.

It will be clear from the above description, that when the shaft 47 is rotated, the crank 86, through the curved link 93 and frame 91, will raise the saw 37 and cut off the lead. Shortly thereafter, and during the same revolution, the cam 85 will engage the arm 88 and oscillate the levers 60 against the plungers 59 and push to one side the lead 35 that has just been cut off.

Referring to Figs. 8, 9, 20, 21 and 22, it will be noted that the right hand side of the opening in the die is always the same distance from the right hand edge of the die, regardessof the dimension of the opening. This is of importance, because the plungers 59 always move just far enough so that the near side of the last lead .or-ruleis shoved just beyond the edge of the die, so that the next lead to be formed will come out on the delivery table close along side of the preceding one.

The nozzles or dies, previously referred togenerally by the number 34, are best shown in Figs. 1, 2, 8, 9, 20, 21 and 22, and form an important part of my invention. Each die is formed in two parts 95, 96 having accurately ground faces 97, 98 so that there will be no leakage of cooling water from the cooling passages 99, 100, which are connected to the pipes 101, 102 carrying cooling water or other fluid. 1

The dies are secured in place in the following manner. A plate 103, clamps 104, and a fixed jaw are secured to the head 29 of the melting pot by means of bolts 105, (Figs. 8, 9, 23), the transmission of heat to the plate being minimized by insulation 106. The fixed jaw 107 has passages connecting with the cooling pipes 101, 102 and passages 99, 100 in the dies. The clamps 104 engage a sliding jaw 108 which is adapted to be adjusted by the hand screw 109 threaded in a fixed thrust block 110. Each of the jaws 107, 108 has a clamp 111, 112, adapted to engage the shoulders 113 on the dies, as best shown in Figs. 2 and 4.

The dies shown in Figs. 20 to 21, as well as all dies to be used in my machine, are interchangeable and can easily be removed or changed. To change from one set of dies to another, the bolts holding the clamps 111, 112 are loosened, after first having shut off the flow of cooling water. The hand screw 109 is then turned to withdraw the sliding jaw 108, after which the die 95, 96 can be lifted out. A new die is then inserted, with the open ends of the cooling passages toward the pipe connections 101, 102. The hand screw 109 and clamps 111, 112 are then tightened and the machine is again ready for operation.

The operation of my machine is continuous and. automatic, and after being set in operation continues to make leads or rules of uniform length stacked on the delivery table, as long as the melting pot is kept supplied with metal. In large printing shops, the machine will be kept in continuous operation, the leads and rules being taken from the-delivery table and used as fast as they are cut off. After being used, the leads and type are not separated, but all are thrown into a common melting pot, which may be the pot of this machine, and remelted for again casting in the form of type or leads and rules, as the case may be.

lrVhile I have shown and described one form of my invention in great detail, it is to be understood that the illustration and description are but illustrative of one form of the invention and not limitations thereon.

lVhat I claim as' my invention and desire to secure by Letters Patent is:

1. The method of making bars of predetermined length from soft metal, consisting in melting the metal, supplying a definite predetermined amount of molten metal to an extruding means, extruding the predetermined amount of the molten metal by pres sure through forming dies, solidifying the metal on its passage through the dies, releasing the pressure when a predetermined amount of the metal has been extruded, cutting off the extruded bar after the pressure has been released, and moving the cut-off bar out of the path of the next bar to be extruded.

2. In a machine of the class described, the combination of a melting pot, a cylinder having a reciprocating plunger and adapted to receive molten metal from the pot, forming dies connected to receive metal from said cylinder and plunger, means for cooling the dies, means for reciprocating the plunger, means for adjusting the stroke of the plunger and the length of the bar being formed,- and means for cutting off the bar when a predetermined length has been formed.

3. In a machine of the class described, the combination of a melting pot, a cylinder having a reciprocating plunger adapted to receive molten metal from the pot, forming dies connected to receive metal from saidcylinder and plunger, means for cooling the dies, means for reciprocating the plunger, means for adjusting the stroke of the plunger and the length of the bar being formed, means for cutting off the bar when a predetermined length has been formed, and means for moving the cut off bar out of the path of the next bar to be formed.

4. In a machine of the class described, the combination of a melting pot, a cylinder having'a reciprocating plunger adapted to receive molten metal from the pot, forming dies connected to receive metal from said cylinder and plunger, means for cooling the dies, means for reciprocating the plunger, means for adjusting the stroke of the plunger and the length of the bar being formed, a table for receiving the bar as formed, means for cutting off the bar when a predetermined,

length has been formed, and means for moving the cut-off bar to one side on the table out of the path of the next bar to be formed.

5. In a machine of the class described, means for extruding metal through a. formmg die to form a bar, a horizontal table for receiving the bar, means for cuttingofl the bar into predetermined lengths to form leads and the like, and plungers operable in timed relation to the cut-off means for stacking the leads on the table.

6. In a machine of the class described, the combination of a cylinder having a plunger therein, means for reciprocating the plunger, means for supplying soft metal to the cylinder on its out stroke and extruding it on the forward stroke, forming dies through which the metal is extruded, means for cutting off the extruded metal, delivery mechanism for moving the cut-off metal out of alignment with the die, clutch mechanism for operating the cut-off means and delivery mechanism during the out stroke of the plunger, and means for rendering the clutch mechanism inoperative during the forward stroke of the plunger.

7. In anextruding machine, a cylinder having a plunger for extruding the material, a plate closing the end of the cylinder and having an orifice therein, a two part die secured to the plate in alignment with the orifice, cooling passages in the die opening through the side thereof, the meeting faces of the die being ground to a close fit, an abutment having cooling passages adapted to register with the die passages, and means for pressing the die tightly against the abutment.

8. In an extruding machine, a cylinder having a plunger therein for extruding the material, a plate closing the outlet end of the cylinder and having an orifice co-axial therewith, interchangeable dies having forming passages of different sizes, and means for securing the dies to the plate with one edge of the forming passage always a fixed distance from the axis of the cylinder.

9. In a machine for extruding material, a cylinder having a plunger therein, means for operating the plunger, a plate closing the outlet of the cylinder and having an orifice therein, a fixed jaw secured to the plate at one side of the orifice, a slidable jaw on the plate on the other side of the orifice, a die having cooling passages therein, cooling passages in the fixed jaw registering with the passages in the die, and means for clamping the die between the jaws.

10. In a machine of the class described, a frame, a cylinder mounted therein, a plunger reciprocatable therein, means for supplying molten metal to the cylinder, a driving shaft, means for driving the plunger from the shaft, adjustable means operated by move ment of the plunger for reversing the driving shaft, means for cutting off the metal extruded from the cylinder, a cut-off shaft for actuating the cut-off means, and means for driving the cut-off shaft from the driving shaft when the latter is reversed.

11. In a machine for forming metal bars and the like, the combination of a cylinder adapted to receive the metal for forming the bars, a die having connection with one end of the cylinder,,a plunger reciprocatable in the cylinder and adapted to force the metal through the die, means for reciprocating the plunger, the stroke of the plunger being less than the length of the cylinder and the unextruded portion of the metal remaining in the cylinder being extruded at the beginning of the next stroke of the plunger, whereby a continuous bar is formed, means for varying the stroke of the plunger, and means controlled by movement of the plunger for cutting oil the bar.

12. In a machine of the class described, the combination of a cylinder having a reciproeating plunger therein, means for supplying a soft metal to the cylinder, forming dies connected to the cylinder to form into bars the metal beingextruded from the cylinder, means for reciprocating the plunger, means for adjusting the stroke of the plunger and the length of the bar being formed, a table for receiving the bar as it is formed, means for cutting ofi the bar when a predetermined length has been formed, and means for moving the cut-off bar to one side on the table out of the path of the next bar to be formed.

13. In a metal extruding machine, the combination of a cylinder and a plunger therein, means for reciprocating the plunger, means for supplying metal to the cylinder to be operated upon by the plunger, interchangeable dies adapted to cooperate with the cylinder plunger for forming metal bars of different cross-section, means for a'djusting the stroke of the plunger in conformit to the cross-section of thebar being forme means for cutting 011' the bar when a predetermined length has been formed, and means for actuatin the cut-ofi means while the plunger is bem retracted.

14. In a mac ine for forming metal bars and the like, the combination of a cylinder having a plunger therein, means for reciprocating the plunger, means for varying the stroke of the plunger whereby the amount of metal extruded on forward stroke will vary with the size of the bar being formed, means for supplying an amount of metal to the cylinder equal to the amount that has been extruded, whereby the bar being extruded will be continuous, means for cutting ofi the bar after the end of the workin stroke of the plunger, and means controlle in timed relation with the movement of the plunger for actuating the cut-0E means.

15. The method of making soft metal bars and the like of uniform length in apparatus having a c linder and plunger of fixed size and interc angeable dies of difi'erent cross section, which consists in supplying an amount of metal to the cylinder equal to the volume of the bar to be formed, Varying the stroke of the plunger proportionally to the volume of the bar being formed, extruding a volume of metal through dies to form a bar of predetermined length, retaining a quantity of metal in the cylinder after each working stroke, cuttin oil the extruded bar after each working stro e of the plunger, and moving the cut-off bar out of the path of the next bar to be formed.

BENJAMIN F. BURT.

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