US2379738A - Servo power application to dies of die-casting machines - Google Patents

Description

July 3, 1945. L.. H. MORIN 2,379,738

SERVO-POWER APPLICATION TO DIES OF DIE `GS'IING MCHINES Filed Aug. 14. 1942 filme Patented July 3, 1945 ,y

`sitltvo Pownn OFFICE 1 DIEfCASTING MAC E'Morin, Bronx, N. Y., miglior' of onchalt toDavis Marinsky, Bronx, N. Y.

Applicativi; august 14, 1942, rsemi No. 454310` (c1. zzz-.ssl

Y )1s claims. This invention relates to die casting machines and to. the operation of dies of machines `of this type and kind. More particularly. the

invention comprises the application of servopower to thevdies, preparatory to the pressure injection of casting material into thedies `to insure firm engagement of the dies and to resist the pressure of the casting material injected into the die; and st ill more particularly to the hydraulic closing of dies of high speed die casting machines. The novel features of the invention will be best understood from the following de scription when taken together with the accompanying drawing, in whichcertain embodiments of the invention are disclosed, and in which the separate parts are designated by suitable reference characters in each of the views; and in which:

Fig. lisa diagrammatic sectional view through I the dies of a casting machine showing the same in closed position. V p l Fig. 2 is a view similar to Fig. 1 showingthe dies in open position; and

Fig. 3 is a view `similar-.to Fig. dies improperly closed. e

In the die casting art, it has been known to provide machines employing hydraulic or pneumaticY pressures for closing the dies. However, this has been accomplished by what may "be termed a direct stroke which involves rather complicated mechanism and a material waste oi power, in that, the entire operation ot the dies has been `throughthe' medium employed. Furthermore such methods of operation are not practically applicable to what might be termed high speed die casting machines.

` It is the purpose of my invention to provide a servo-power" application to the dies, momentarily at the point of the cycle when the dies are to be held iirmly closed, that is to say, when the casting material is pressure injected into these dies. In other words, this application oi power or pressure in closing the dies is employed in conjunction with and as part of the other me-v chanical means for moving the dies toward and from each other. Furthermore, safety means are employed to preventinjury or'dstruction to the dies and other working parts of the machine, and also to eliminate `accidents which might occui,l by pressure injection of casting material into improperly closed dies, bythe squirting oi' this material beyond the limits of the dies'orthe die U1 showing the the` machine is provided, particularly from the standpoint oi die operation. Y

From the standpoint of mechanical operation l f the dies, lherein diagrammatically illustrated and described in brief, reference can be made to the morespecic disclosure ofthe `entire opferatl'lg structure in U. vSi. patents, 1,975,966

`dated October 9, 1934, and 2,193,832 dated March e 19, 1940, in which patents are illustrated types of casting machines to which the present invention is applicable. y It will be understood, however, that the disclosure of the invention in this respect is only illustrative of one `adaptation and use of my invention.

In the accompanying diagrammatic illustrat' tion, the mechanism controllingldie operation is applied to only one oi' the dies, the other die being shown only in part, but it will be apparent that the same structure will -be used in .conjunction'with both dies. particularly in casting machines where both dies are movable relatively toeach other and away from a core which supports the nished casting and which is used` to eject the casting from the impression or cavity of bothdie parts.

In the drawing, I0 represents each die part.

'I'hese die parts are moved toward and from each other by die operating slide rods Il having angular key elements I2 fitting in corresponding grooves I3 in the die parts so that," as the rods Il move back and forth at right angles tothe longitudinal plane of thedie parts I0, the dies are opened and closed asis specifically taught in cavity. Further, by reason of the momentaryv the patents hereinbefore cited. l

' With the fpresent structure, the die parts are each provided with long bores or passages I I, which form cylinders, into which a hydraulic or other pressure medium may be injected through pipes or tubes I5 communicating with admission ports I6 which open into the cylinders I4 adjacent the ends of the die parts having the vcav-- ities I1.

In` the cylinders I4 are arranged pistons or plungers I8; which extend through the outer ends of the die parts and have enlarged heads I9 provided on outer surfaces with projecting `control fingers or dogs 2l) which form extensions on the piston, which operate in conjunction with pawls 2|. l I

Supported on the outer end of the dies are pins 22 which pass through openings in the enlargement I9 `of the pistons, and `springs 23 are mounted on the pins outwardly of` the enlargement and tension of these springs is controlled byadjustment nuts 2l arranged on the pins 22. 'l'he springs 22 maintain the pistons Il in normal inwardly projected arrangement in the cylinders I4, which inward movement is checked by stops 2i.-

The pawls 2| are rotatably supported on shafts 2t, the pawls comprising a finger 21. notched as seen at 28, to engage the outer end of the dog 2l, as seen in Fig. l of the drawing. The pawls 2| also include a finger 29 adapted tooperatively engage a micro-switch 30 or the sensitive plunger 2| of said switch for purposes later described. At 32 is shown a rod pivoted to the pawl 2| for actuating said pawl in the cycle of operation of the machine to bring the pawl into the position shown in Fig. l slightly in advance of the appli- Vcation. of the servo-power" and also to raise the as'zavss duced into the cylinder", but lsince the piston is unsupported by the pawl anger 21, this pressure will operate to move the piston I2 outwardly; as indicated partially in dotted lines in Fi'g. 3 against the action of the spring Il, the dog 2l sliding under the ilnger 21 in this operation. The switch 30 ,controls the application of hydraulic pressure to the casting material and in order for the casting material to be injected into the dies, the switch plunger 3| must be depressed slightly. Failure to operate this switch renders the pressure injection of the casting material inoperative,

' thus accidental discharge or squirting of the finger 21 to allow normal .opening of the dies after the casting has been formed. as is indicated in Fig. 2.

The cycle of operation of the machine will be readily understood from the foregoing description when taken in connection with the diagrammatic illustrations in the drawing and the following statement. Considering Fig. l, itwill be assumed that the dies Il have been moved into closed position and the pawl 2| brought into theposition to engage the dog in the recess 28 of the finger 21 of the pawl. At this time and through v suitably controlled means oil or other pressure element is introduced into the cylinders il through the tubes or pipes I5, .thus applying the "servo-power to the dies lli to firmly support the same in closed position. In the same instant or very shortly thereafter in the cycle of machine operation, casting material is pressure injected into vthe dies at the parting line thereof through 'a gate or admission passage, not shown, in that it is disposed at right angles to the dies, to form a casting I4 in thecavities i1 and around a core pin 35. Immediately thereafter the hydraulic or other pressure is released from the cylinders I4 and the dies are moved into open position as illustrated in Fig. 2, the pawl 2| having been raised through operation of the rod 22, 'as will be apparent. After removing the casting,

' .that the moment of application of the servopower in each cycle of machine operation represents in fact a small fractional part of each complete cycle of machine operation and a fraction of a second. l

In Fig. 3 of the drawing is diagrammatically illustrated the fool-proof operation of the machine, for example, in the event that the dies il! become improperly closed' by the presence of some foreign particle, as indicated atr in Fig. 3

l between adjacent surfaces of the dies Il. In

such instances the dog 20 will check downward movement of the pawl 2| or the finger 21 thereof so that this finger will rest upon the upper surface 31 of the dog, thus maintaining the finger 22 out of operative engagement with the plunger 2| of the switch l0. The machine will perform its normal operation. In other words, the hydraulic or other pressure medium will be introcasting material through the partially closed dies i machines of this type and kind, suitable signal or destruction 4to the dies is obviated.

It will lbe apparent that the pawl 2| operates in the mannerof a latch, which may be saidqto engage a bolt 2li, the dog extension on the piston, in checking outward movementof the piston and will be constructed in such manner as to provide the required backing up of 'thepiston to care for the application of the "servo-power" in closing and holding the dies closed for the moment of pressure injection of the' casting material.

f `In the diagrammatic illustrations. all structural 'details with respect to packings of Ithe pistons, etc. -have been omitted as these are all well known in the arts. Furthermore, the invention is applicable to die casting machines of various types and kinds and in fact to any type and kind of mechanisms where it is desirable to apply a final pressure or stroke upon a moving part which has been otherwise moved into a predetermined position. In accordance with the present teachings, the medium employed is introducedl b etween the moving part and what might be termed a backing member, automatically actuated means being employed controlling operative positionk of the backing member and otherwise controlling operation of the machine or apparatus.

Having fully described my invention, what I claim as new and desire to secure by Letters a backing for each die and movable relatively to the die. means` for injecting a pressure medium i said member in operative position.

asvavae a backing for each die and movable-relatively to the die, means for injecting a pressure ,medium between the die and said backing member tc move the die into closed position, means controlling the operative backing up position of said member, said last named means comprising a bolt on said member, a latch engaging the bolt to support said member in operative position, and means preventing operative engagement of the latch with said bolt in improper, mechanical, closing movement of the die.

4. In die casting machines, a pair of dies movable toward and from each other, mechanical means for actuating said dies, a member forming a backing for each die and movable relatively to the'die, means for injecting a pressure medium between the die and said backing member to move the die into closed position, means controlling the operative backing up position of said member, said last named means comprising a bolt on said member, a latch engaging the bolt to support said member in operative position, means preventing operative .engagement of the latch with said bolt in improper. mechanical, closing movement of the die, and said last named means including means preventing injection. of casting material into improperly closed dies.

5. In a die casting machine, a pair of dies movable toward and from each other, said dies having cylinder portions, pistons operating in the die cylinders, means comprising a latch adapted to operatively engage the piston of each die cylinder, means for controlling normal mechanical movement of the dies toward and from each other, and means for introducing a pressure medium between the dies and said pistons tosustain the dies in closed position, while said pistons are backed by said latch controlled means.

6. In a die casting machine, a pair of dies movable toward and from each other, said dies having cylinder portions, pistons operating in the die cylinders, means comprising a latch adapted to operatively engage the piston of each die cylinder, means for controlling 5normal mechanical movement of the dies toward and from each other, means for introducing a pressure medium between the dies and said pistons to sustain the dies in closed position, while said pistons are backed by said latch controlled means, and means providing yieliiable movement of the pistons relatively to said dies.

7. In a die casting machine. a die, mechanical means for moving the die into open and closed positions, said die having an elongated cylinder, a piston in said cylinder and projecting outwardly through one end of the die, means in the die for introducing a pressure medium into the cylinder at the other end of said piston to move the die into closed position, means operatively engaging the rst named end of the piston to i'orm a back' ing maintaining the piston against movement in the aforesaid closing movement of said die, and means releasing said last named means `in moving the die into open position.

8. In a die casting machine, a die, mechanical means for moving the die into open and closed positions, said die having an elongated cylinder,

a piston in said cylinder and projecting outwardly through one end of the die, means in the die for introducing a pressure medium into the cylinder at the other end of said piston to move the die into closed position, means operatively engaging the first named end o! the piston to :om s backing maintaining meetwaarden movement in the aforesaid closing movement of said die, means releasing said last named means in moving the die into open position, and said backing means comprising va latch engaging a projecting bolt on said piston.

9. In a die casting machine, a die, mechanical means for moving the die into open and closed positions, said die having an elongated cylinder, a piston in said cylinder and projecting outwardly through one end of the die, means in the die for introducing a pressure medium into the cylinder at the other end o! said pistonv to move the die into closed position, means operatively engaging the first named ond of the piston to form a backing maintaining the piston against `movement in the aforesaid closing movement oi said die, means releasing said last named means in moving the die into open position, said backing means comprising a latchv engaging a proiectins bolt on said piston, and spring means supporting` the piston in predetermined position in the cylinder of the die and providing relative movement between the die and piston.

10. In a die casting machine employing mechanically actuated dies movable toward and` from each other, in moving the dies into closed and open positions, means for applying servopower to the dies in closing and holding the dies closed during pressure injection ot casting material into the dies, and means automatically relieving the servo-power application in the event o! improper mechanical closure of `said dies.

11. In a die casting machine employing mechanically actuated dies movable toward and from each other, in moving the dies` into closed and open positions, means for applying servo-power to the dies in closing and holding the dies closed during pressure injection of casting material into the dies, means automatically relieving the servopower application in the event of improper mechanical closure of said dies, and said last named means including means e stoppingpressure injection of casting material into improperly closed.

dies.

12. The combination with dies of a die casting machine, of a backing member i'or the die,means cooperating with said member. retaining the same in fixed backing-up position, means yieldably coupling the die with said member, and means for introducing a pressure medium between the backing member and the die in applying servopower to the die in supporting the die in closed position.

13. In an apparatus of the class described, an element movable into open and closed positions, means for moving said element, said element having a cylinder, a piston in said cylinder, yieldable means coupling the piston and element providing movement therebetween, while normally maintaining predetermined position of the piston in the cylinder of said element, a catch device automatically movable into and out of engagement with said piston tov form a backing for said piston maintaining a predetermined position thereof, and means for introducing a pressure medium into the cylinder of said element vto move the element relatively to the piston, while the piston is maintained in backed position. 4

14. 'I'he combination with a die of a die casting machine having means mechanically moving the die into open and closed position, of a backing member movable with the die in normal opening and closing movement thereof, means automatically engaging said member tc support the same in backIng-up position, and means iniecting a pressure medium between the backed up member and the die to urge the die in a direction away from said member in moving the die into closed position.

15. In a die casting machine employing dies movable toward and from each other, mechanical means for actuating said dies, each die having a cylinder and a backing member therein, andmeans for introducing `a pressure medium into 10 16. In a die casting machine employing dies movable toward and from each other. mechanical means for actuating said dies, each die having a cylinder and a backing member therein, means for introducing a pressure medium into said cylinders between said backing members and dies for applying holding pressure directly to the dies at the moment of forming a casting within said dies, andmeans controlling the last named operationof said dies. v 4

i LOUIS H. MOREL

Images