US2178032A - Forging machine - Google Patents

Description

Oct. 3l, 1939. C; CLAUSEN 2,178,032

FORGING MACHINE Filed March 25, 1936 INVENTOR Z0 12 21 Engl.,

ATTO RN EYS Patented Oct. 31, 1939 u UNITED STATES PATENT OFFICE FORGING MACHINE Charles Clausen, Detroit, Mich., assigner to Standard Forge Company, Detroit, Mich., a

corporation of Michiganl Application March 23,

Claims.

This invention relates to a forging machine and more particularly to a machine embodying die blocks for hot forging operations, and an object is to maintain the work at a high temperature,

v5 after contact therewith of the dies during the forging operation.

It is also Van object to provide electrical means for applying heat to the work and dies during the forging operation, and to provide means whereby the heating current is automatically applied by the movement of a die into Contact with the work.

It is also an object to provide certain other new and useful features, all as hereinafter set forth, reference being had to the accompanying draw-- Aing, wherein:

.Figure l is a central vertical section through the die blocks and adjacent parts of a machine illustrative of an embodiment of the present invention; Fig. `2 is a horizontal section upon the line 2 2 of Fig. l, and

Fig. 3 is a view drawn to a reduced scale show ing the complete machine in side elevation and a wiring diagram in connection therewith.

In the operation of forging hot metal in dies, the billet which is heated to a very high degree, cools very rapidly upon contact of the die or dies therewith, thus interfering with the forging operation and affecting the granular structure of .the forging due to such cooling before the forging ,operation is completed and the maintaining of ythe billet at a substantially uniform temperature is therefore essential to secure the best results.

In Fig. 3, a forging machine of a certain construction is shown, but it will be understood that the same is merely illustrative of one form suitable for the purpose, and that the present invention may be applied to any well known forging machine embodying dies of suitable form to give the work the desired shape, upon the application of power in any desired manner to move the dies relatively toward and from each other, and form the work therebetween. In this Fig. 3, I indicates a heavy frame having side legs connected at their upper ends by a fluid cylinder 2 and forming an arch, there being a piston 3 in said cylinderhaving a heavy piston rod i projecting from its lower end'and formed with a head 5 on its lower end to the underside of which is bolted a second head l by bolts l with an insulating material 8 between said heads and between said bolts and head 6 to completely insulate electrically, said head from the rest of the machine.

' On the lower side of the head or disk 6, said head is formed with an axial hub or boss 9, to the 193e, serial No. 70,292

end face of which hub is bolted a disk I0 having an axial hole to receive a punch pin II having a head on its upper end within a recess in the end ofthe boss, and thus said punch extends downwardly at the axis of said boss to engage within 5 an axial opening in an upper or movable die block I2 which is attached to opposite sides of the hub or boss 9, by brackets I3 bolted at their lower ends to the upper side of said block and connected adjacent their upper ends to said hub by studs I4 10 on said bracket arms projecting into slots I5 formed in the sides of said hub. The die block l2 is thus suspended from the hub 9 of the head 6 to be raised or lowered with the head 5 as the piston 3 is moved in its cylinder, said die block 15 having lost motion relative to said head due to said pin and slot connection of said brackets I3 -to said hub. This lost motion permits the block to drop away from the hub so that the lower end of the punch II will lie within its opening in the 20 blockand just above a recess I6 which forms a continuation of said opening and opens through a boss I 'I on the bottom of said block.

The upward movement of the head 6 is limited by means of brackets I 8 bolted at their lower ends 25 to the bed or base of the machine at opposite sides Tof the die block I2 and have upper ends projecting over the periphery of said block. Inside of these brackets directly beneath said block is a lower or fixed die block I9 rigidly secured to the 30 base or bed of the machine by long bolts 2G passing through openings in the block and into the base, said bolts and blocks being electrically insulate'dvas at 2 I, one from the other and from said base. Said fixed die I9 is formed with a recess 35 22 inits upper side to receive the boss Il on the upper movable die and a second recess 23 provides the die cavity within which the forging is formed, the same as shown, being in the form of a disk with an axial hub at its lower side, this hub being 4o formed within an axial opening through the block and above a plug 24 in the opening, and 25 indicates the hot billet of cylindrical form set on end upon the upper end of the plug 24 with its upper end directly below the recess I6 in the movable 45 die so that upon descent of the upper block I2, the billet will rst come into contact with the upper die by entering said recess, and as pressure is applied, the die will move up until it strikes the lower end of the hub 9, the punch Ii 50 simultaneously moving down through the block into Contact with the billet. The shape of the dies will of course, be changed according to the shape ofthe article to be forged, but it is preferable torbring the dies into direct contact with the work in a manner to create a momentary dwell just as contact is made, this being effected by the lost motion between die block l2 and the hub 9 of the head 6.

As soon as the hot billet is put in place, it begins to cool very rapidly particularly as soon as the upper die contacts therewith, and to counteract such cooling, an electric circuit is set up through the two diefblocks, one wire of the circuit being secured at 2b to the head 6 of the machine which head is insulated from the rest of the machine, and the other wire is attached at 21 to the fixed block i9 which is also insulated vfrom the remainder of the machine. As long as the die blocks are separated and not in contact with interposed work, no current will flow but just as soon as the upper die descends into contact with the billet, a current of high --amperage will flow from one block to the other through the -work which is of comparatively small area, and the biliet wil be immediately heated suiiiciently to maintain it at the proper forging temperature.

To obtain such a current of high amperage and low voltage, a transformer is introduced into the current flow from the main supply line vindicated at 23, the primary circuit 29 including the usual primary coil 3i), an automatic switch 3| and any suitable circuit breaker switch 32 operated by up and down movement of the head 5 or other part of the machine movable 'with the upper die. Current flow through the primary coil induces current now in the secondary coil 33 and secondary circuit 34 which includes the die block l@ and head t to which the terminals 21 and respectively, of this circuit are connected.

The upper or movable die l2 is moved by fluid pressure entering the opposite ends of the cylinder 2 and controlled by a suitable reversing valve 35 in the supply line 36.

In operation, after placing the billet 25 upon the lower die l!) beneath the upper die I2, the valve 35 is operated to cause the upper die to descend, first bringing it into contactwith the upper end of the billet, thereby closing the secondary circuit t4 and simultaneously therewith, operating the switch 32 to close the primary circuit 29. This first contact of upper die with the work thus effects a rapid heating of the work due to the difference in areas of die and work, and this heating is continued until the forging operation is completed and movement of the upper die is reversed, this up movement breaking the circuit as the die leaves the work, and by a further up movement, the switch 32 is opened. By this arrangement, the work is heated throughout the forging operation, sufficiently to prevent undesirable cooling and the operation is facilitated and better forgings secured.

Obviously any suitable construction of forging machine proper, may be employed and other forms of electrical heating and control means may be used without departing from the vspirit of the present invention, and such changes are contemplated.

I-Iaving thus described my invention what I claim is:

l. In a forging machine, wherein opposing die members are relatively movable into en gagement with a preheated blank, made operative tov shape the engaged blank into -desired form by pressure applied to one of said members and thereafter moved relatively in the opposite directionto release the shaped and formed product, said machine including means for moving said members relatively with a 'dwell in said movement"`into engagement with the blank interposed therebetween, and an electric heating circuit within Which said members are connected and which circuit is closed by the bringing of one of said members into contact with said blank to reheat the latter through substantially its entire length during said dwell.

2. In a forging machine, wherein opposing die members are relatively movable into engagement with a preheated blank, made operative to shape the engaged blank into desired form by pressure applied to one of said members and thereafter moved relatively in the opposite direction to release the shaped and formed product, said machine including ineans for electrically insulating each of said members from other parts of said machine, said members each comprising an electrode, a heating electric circuit within which circuit said members are connected for completing the circuit through said members and said blank by the movement of one of said members into Contact with said blank, and means for moving said members with a dwell in said movement -upon contact between said blank and members and the closing of said circuit.

3. In a forging machine, wherein opposing die members are relatively movable into engagement with a preheated blank, made operative to shape the engaged blank into desired form by pressure applied to one of said members and thereafter moved relatively in the opposite direction to release the shaped and formed product, said machine including means for moving said members relatively with a dwell in said movement into engagement with the blank interposed between said members, an electric circuit the terminals of which are electrically connected to said members, said members being separately insulated from the other parts of said machine, and said circuit through said members and blank being completed by al movement of one of said members into contact with said blank and adapted for substantially constant and uniform heating of said blank during said dwell and said forging operation.

4. In a forging machine, wherein opposing die members are relatively movable into engagement with a preheated blank, made operative to shape the engaged blank into desired form by pressure applied to one of said members and thereafter L moved relatively in the opposite direction to-release the shaped and formed product, said machine including a fixed die and a movable die each being separately insulated from the other parts of said machine, each of said dies comprising an electrode, means for moving said movable die with a dwell in its movement toward and away from said die, said blank being supported by but separate from one of said dies, an electric heating circuit within which said dies are connected for heating said blank, said circuit including primary and secondary windings to be closed by the contact between said blank and one of said dies for uniformly heating said blank during said dweil, means within said primary circuit for closing said circuit, and a switch controlling said means engageably operable with the movement of said movable die.

5. A forging machine including a fixed die, a movable die in opposed relation to said fixed die. a movable carrier member upon which said movable die is mounted for movement relative to said carrier, power means for moving said movable die and carrier toward said fixed die to forge work interposed between said dies, said moveto be closed by a movement of the movable die into Contact with the work and to be opened by a movement of said die out of Contact with the work, and a, switch device operated by a movement of the movable die out of Contact with the 5 Work, to open said primary circuit.

CHARLES CLAUSEN.

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