US3127644A - Pressure casting apparatus - Google Patents

Description

April 7, 1964 H. FLECKENSTEIN ETAL 3,127,644

PRESSURE CASTING APPARATUS Filed June 27, 1960 2 Sheets-Sheet 1 Fly. 1

Jnvenlor:

//,4N5 FLECKE/VSTE/N GUNTHEE HAAG mun April 7, 1964 H. FLECKENSTEIN ETAL 3,127,644 PRESSURE CASTING APPARATUS Filed June 27, 1960 2 Sheets-Sheet 2 H/z/vs F4 [Chf/VS TF/N GUNTHER HAAG United States Patent mazes-4 PRESSURE CASTlNG APPARATUS Hans Fleckenstein and Gunther Haag, @ldenhurg in Gidenhurg, Germany, assignnrs to Lieentia Fatent Vervvaltungs G.rn.b.H., Frankfurt am Main, Germany Filed June 27, 196i Ser. No. 39,133 Claims priority, application Germany July 1, H59 3 Claims. (or. 22-68) The present invention relates to a pressure casting apparatus having a multiple arrangement of molds on a feed mechanism, more particularly to a pressure casting apparatus wherein the mold is comprised of several portions with the bottom portion being fixedly mounted on the apparatus and the upper portions being arranged on a feeding mechanism for successively engaging the fixed lower mold portion. In those instances where the mold is comprised of a plurality of portions one of the portions may be mounted on a mold closing plate and other portions may be rigidly attached to those parts of the casting apparatus which are not included in the feeding mechanism.

The pressure casting apparatus of this invention is of the type wherein the molds are moved in a horizontal direction for closing and opening the molds. A plurality of molds are employed in order to increase the output of the casting apparatus.

While many different kinds of pressure casting machines have been devised, most of the improvements are concerned with the mechanism for opening and closing the mold, the pressure cylinder, the filling and pressure chambers, and the relationship of these components with respect to each other. The different kinds of casting machines are devised for particular purposes, such as to readily accommodate a particular casting material, for making either large or small castings, for employing either single or multiple molds, and for the use of complicated molds either with or without inserts.

In addition, pressure casting machines have been devised solely for the purpose of increasing the output of castings per unit time. One form of a high production pressure casting machine comprises arranging a plurality of either filling chambers, pressure chambers or feeding units so that these components are moved successively into working position with respect to one of the molds. In another form of the high production casting machine a plurality of similar molds are moved successively beneath the discharge opening of a crucible and are successively filled with the casting material.

Both of the above described high production casting machines employ different auxiliary devices since in one case the purpose is to decrease the time of feeding the casting material While as in the other instance the total time for casting is decreased by the use of a plurality of molds.

It has been found that the most economical use of a pressure casting machine is attained by using a machine comprising a plurality of molds. The present invention relates to such a pressure casting machine and has great advantages over known pressure casting machines even though the construction of the present machine is considerably simplified. In addition, the present pressure casting machine has features other than merely arranging a plurality of molds in a feeding mechanism which moves the mold successively into a casting position.

In the present invention exchange mold halves are arranged on a feeding mechanism which is capable of moving the mold halves into and out of engagement with a single stationary mold half which is secured on the pressure cylinder of the casting machine. If the mold is comprised of more than two portions, the exchange portions of the mold are mounted on the feeding mechanism.

3,127,644 Patented Apr. 7, 1964 The feeding mechanism is also capable of rotary movement so as to successively move the exchange mold halves into operative position with the stationary mold half to conduct a casting operation. During each casting cycle the castings are removed from the exchange mold halves and these halves are prepared for a subsequent casting process. The number of cycles of operation and the sequence of the cycles is determined by the type of casting to be accomplished.

A four cycle sequence is preferable for castings of medium size comprising a light metal in which iron inserts are employed. In this sequence the following cycles occur:

(1) The actual casting of the material and cooling of the material to solidification;

(2) Ejection or removal of the casting from the mold;

(3) Cleaning of the mold;

(4) Positioning of the insert in the exchange mold half.

The stationary mold half is always cleaned following each casting operation by an automatic mechanism which moves into and out of position after each cycle of the casting process.

The present invention is not limited to the use of molds comprising only two parts. It is also possible to use molds comprised of three portions providing the cast ing mold is closed in one axial direction. When three part molds are employed, the central part of the mold acts similarly to the exchange mold half in the two part mold and the exchange part of the three part mold which like the lower mold part is needed only during the actual casting operation is mounted on the mold closing plate positioned opposite the stationary mold part. The stationary mold part is attached such as by screws to the stationary platen.

When a mold is employed having more than three parts the additional parts are generally fixed to the feeding mechanism of the pressure casting machine. However, in some instances, additional mold parts can be mounted on stationary portions of the casting machine which portions are other than the feeding mechanism.

Another feature of the pressure casting machine of this invention is the construction of the feeding mechanism so as to comprise an annular member which is rotatably mounted and is rotated by means of power transmitted through a gear system drivingly engaging an internal gear on the annular member. The exchange mold halves are mounted on the annular member so that rotation of the annular member will successively move the exchange mold halves into position for the casting operation. The opening and closing of the mold is achieved by movement of the feeding mechanism, including the annular member, toward and away from the stationary mold half which is fixedly mounted on the casting apparatus.

In order to prevent any bending of the annular member during the opening and closing of the mold, the movement of the movable plate is synchronized with movement of the annularmember. This synchronization occurs during the last stages of the mold closing movement and the initial stages of the mold opening movement. This synchronization is achieved by supporting the piston rod of the hydraulic cylinder, which moves the annular member, on an arm extending from the mold closing end plate.

It is therefore the principal object of this invention to provide a novel and improved pressure casting machine which is capable of increased production but which has a simplified construction.

It is another object of this invention to provide a high production pressure casting machine wherein a plurality of exchange mold halves are successively brought into a 3 casting position with respect to a fixedly mounted i.e. stationary mold half.

Other objects and advantages of this invention will become apparent upon reference to the accompanying description when taken in conjunction with the following drawings:

FIG. 1 is a front elevational view of the pressure casting apparatus of this invention;

FIG. 2 is a top plan view of the pressure casting apparabus; and

FIG. 3 is a sectional view of the pressure casting apparatus taken along the line 33 of FIG. 1 and looking into the direction of closing the mold.

With reference to the drawings wherein like reference symbols indicate the same parts throughout the various views, a specific embodiment of the pressure casting apparatus of this invention will be described.

With respect to all iigures an annular member 1 is mounted within a stationary frame 2 which is a component of the pressure casting apparatus. The pressure casting apparatus further comprises a frame 29 secured to frame 2, a pressure cylinder 3 for feeding the casting material into the mold, a stationary platen 4 on which the bottom portion of the mold is mounted, a movable mold closing end plate, (movable platen 5) which is aligned with the stationary mold half, and a plurality of pairs of guide rods 6. The inner surface 31 of the annular memher 1 having a gear ring 3 1, is rotatably mounted on two pairs of rollers 7 and 8 with the rollers being mounted inside of a bearing housing 9.

The non rotatable bearing housing is movably mounted, and movement is eifected by a piston rod 11 of a power piston, housed in stationary cylinder 11. The bearing housing 9 engages member 1 and it is slidably mounted on rods 12 which extend between portions of the frame 2.

Housing "9 is secured to rod 10. Frame 2 is substantially comprised of two walls secured to each other by means of bolts 24. The annular member 1 is rotated through a power transmitting system which comprises a rack and pinion gear arrangement 13, wherein the rack is connected with a control piston and cylinder arrangement which is not illustrated. The pin-ion gear 26 is operated upon by the rack and is in turn drivingly connected to a sprocket 25, which in turn is driving a chain 14, a driving gear 15, and the latter is dnivingly engaged with gear teeth 16 on the inner surface 31 of the annular member 1, so as to form an internal gear. It will be apparent from the foregoing, that the rack and pinion arrangement 13 rotates member 1, while piston rod Ill displaces member 1 in axial direction.

A plurality of exchange mold halves 1'7, in this instance four, are mounted on the annular member 1 with the number of the mold halves corresponding to the cycles of the sequence of operation of the casting process, as will be subsequently described, when the castings remain in the exchange mold halves upon the opening of the molds.

A single stationary mold half 18, which completes the mold with any of the exchange mold halves 17, is mounted by screws onto the stationary platen 4. There is a control disc 27 for the entire machine.

In order to close the mold, the mold feed mechanism which comprises the annular member 1 with housing 9 and molds 17, is first moved by the piston rod of the cylinder 11 towards the stationary mold half r18. The movable platen 5 having a block 31 is moved, in FIGS. 1 and 2 of the drawing to the right, and holds the mold closed during the actual casting process. The mold is closed by means of conventional L-shaped levers 2x8 urging platen 5 towards that one of the exchange mold halfs 17 which already engages stationary mold half 18. Platen 5 is guided on and along rods 6. In closed position of the mold the end of an arm 19 which extends from platen 5, engages the outer end of the piston rod 10 and thus additionally completes the mold closing movement. Thus, the mold is actually closed by the arm 10. In the same manner the arm 1'9 prevents a premature opening of the mold when the opening of the mold is caused by movement of the feed mechanism through means of the cylinder '11. Thus, it can be seen that during both the opening and closing of the mold, any bending of the annular member 1 on its guides 12 is prevented.

Arm 19 also prevents an advancing of the opening by means of pistons 11, because even during the opening process rod 16 still rests against arm 19. Rod 10 can follow only the retracting movement of platen 5 in keeping engaged with arm 19. In any of these cases, bending of member 1 or its clamping on rods 12 is effectively prevented.

Upon returning the feed mechanism to its starting position after the mold has been opened following the casting operation, the annular member 1 is rotated by an angle of by the power transmission system (rack and pinion gear 13) in a counterclockwise direction as viewed in FIG. 3 of the drawings. Accordingly the second one of the exchange mold halves 17 is positioned in front of the stationary mold half 18. During the rotary movement of the annular member 1 a nozzle arrangement 20 is moved in front of the bottom mold half by a piston 21 to clean the bottom mold half by compressed air discharged from the nozzle arrangement 2b. In actual practice, the nozzle arrangement 20 comprises a plurality of nozzles positioned to cover the entire inner surface of the bottom mold half. immediately after completing the cleaning of the stationary mold half 18, the nozzles 20 are returned to their original position which is shown in FIG. 1 of the drawings.

While the second exchange mold half 17 is being moved into a mold closing position after rotation of the annular member through 90, the casting which has now cooled is ejected from that one of the exchange mold halves now containing the casting. Ejection is carried out by the piston rod 22 of the removal or ejection cylinder 23, which rod 22 pushes towards the right for such ejection. This ejection occurs when the casting is in its second position. As seen in FIG. 3 of the drawings the second position is shown as the uppermost of the exchange casting halves 17.

In the third position of the member 1, the exchangeable mold half is in the left hand position as seen in FIG. 3, and thus exchange mold half is cleaned such as by applying compressed air against the surfaces thereof.

In the fourth position any inserts which are to be placed in the casting are inserted in the exchange mold half. Such inserts may comprise bridge portions for rotors of electric motors.

The exchange mold half with the inserts in place is then rotated into the number 1 or casting position which is the right hand position as seen in FIG. 3 of the drawmgs.

Thus, it can be seen that the present invention provides a high production pressure casting apparatus which is extremely simple in operation and construction. Further, the minimum of moving parts provides for long troublefiree operation and reduces maintenance costs and downtime of the apparatus. It is to be borne in mind that the number \of upper mold halves mounted on the annular member can be varied in accordance with the various steps which are to be conducted during the casting operation. Further, the use of the casting apparatus of this invention is not limited to molds comprising two parts, but may be readily adapted for use with molds having three or more parts.

It will be understood that this invention is susceptible to modification in order to adapt it to different usages and conditions, and, accordingly, it is desired to comprehend such modifications within this invention as may fall within the scope of the appended claims.

We claim:

1. in a pressure casting apparatus having a multiple mold arrangement, the combination of a stationary frame, a stationary mold half secured to said frame, a pair of parallel rods mounted on said frame, a bearing housing slidably mounted on said rods, two pairs of rollers mounted inside and on said bearing housing, an annular member rotatably supported on its inner annual surface by said two pairs of rollers, and a plurality of exchange mold halves mounted on said annular member and capable of both rotary movement and movement toward and away from said stationary mold half for casting operations, said rods extending in the direction of said last mentioned movement.

2. -In a pressure casting apparatus as claimed in claim 1 wherein said annular member comprises an internal gear, a driving gear meshing with said annular disc internal gear, a rack and pinion gear arrangement, and a driving chain connecting said pinion gear and said driving gear to transmit power from said rack and pin-ion to said annular disc.

3. In a pressure casting apparatus the combination as claimed in claim 1, comprising, in addition; a stationary power cylinder; a piston rod in said cylinder connected to said housing for engaging said member.

References Cited in the file of this patent UNITED STATES PATENTS 1,239,808 Morris Sept. 11, 1917 1,989,812 Lester Feb. 5, 1935 2,054,476 Derry Sept. 15, 1936 2,329,346 Golf Sept. 14, 1943 2,476,219 Purinton July 12, 1949 2,570,325 Dalton Oct. 9, 1951 2,848,771 Eggenberger Aug. 26, 1958 3,063,108 Gardner Nov. 13, 1962

Claims (1)

1. IN A PRESSURE CASTING APPARATUS HAVING A MULTIPLE MOLD ARRANGEMENT, THE COMBINATION OF A STATIONARY FRAME, A STATIONARY MOLD HALF SECURED TO SAID FRAME, A PAIR OF PARALLEL RODS MOUNTED ON SAID FRAME, A BEARING HOUSING SLIDABLY MOUNTED ON SAID RODS, TWO PAIRS OF ROLLERS MOUNTED INSIDE AND ON SAID BEARING HOUSING, AN ANNULAR MEMBER ROTATABLY SUPPORTED ON ITS INNER ANNUAL SURFACE BY SAID TWO PAIRS OF ROLLERS, AND A PLURALITY OF EXCHANGE MOLD HALVES MOUNTED ON SAID ANNULAR MEMBER AND CAPABLE OF BOTH ROTARY MOVEMENT AND MOVEMENT TOWARD AND AWAY FROM SAID STATIONARY MOLD HALF FOR CASTING OPERATIONS, SAID RODS EXTENDING IN THE DIRECTION OF SAID LAST MENTIONED MOVEMENT.

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