Abstract: A mold closing unit has a multi-way valve in a hydraulic supply line leading to a hydraulic traveling cylinder which is controlled as a function of a speed pattern specified for the movable mold clamping plate. The valve body of this multi-way valve is arranged on an elongated, threaded rotatable spindle in an axially movable manner. The spindle is connected with a stepping motor which is controlled as a function of the speed pattern. As soon as the movable mold clamping plate has reached a predetermined distance from the stationary mold clamping plate, the stepping motor is switched to a higher number of steps per revolution and the mold is closed below the creep rate.

Abstract: A press control system for presses fitted with floating platens or tools employs hydraulic cylinders and a spring loaded accumulator to bias the floating element against position change on press closure. The hydraulic pressure in the bias system is compared with floating element position to detect abnormal pressure-position relationships.

Abstract: A hydraulic actuator assembly for a push-type die closing unit of an injection molding machine which has a central, internally bypassable power piston, lateral cylinders for rapid opening travel and a rearward stationary plunger for rapid closing travel, the lateral travel cylinders and the pressure spaces of the power cylinder creating a differential effect under which a small external flow volume of pressurized fluid is required from the pump to produce rapid opening and closing travel while a much larger internal flow volume passes through a flow connection between the cylinders. A program-controlled proportional-response throttle valve in this flow connection gives an accurate and steady control over the travel speeds, especially during deceleration. The throttle valve also makes it possible to obtain a forcible initial die opening movement.

Abstract: An hydraulic press for pressing plastic mats reinforced with glass fibers into formed parts, which press has a stationary and a slidable cross-piece as well as a press drive which drive for driving the slidable cross-piece has at least one adjusting cylinder with a stroke length corresponding to the working range of the press and at least two couplable press cylinders of short stroke wherein for coupling each press cylinder to the slidable cross-piece a coupling rod and a clamping means is provided, the press being distinguished in that in order to better accomodate incorporation of the press drive into an existing press, each press cylinder has a hollow lifting body through which an associated coupling rod is guided, and for coupling the lifting body to the associated coupling rod a clamping device is included on the lifting body.

Abstract: A hydraulic clamping apparatus including a base, a first support means for supporting a first mold and retained by the base and a second support means for supporting a second mold and retained by the base means, the second support means being movable relative to the base means along a path so as to move the second mold into engagement with the first mold. A first hydraulic actuator comprises a first cylinder, a first piston retained thereby, and a rod coupled between the first piston and the second support means. The first actuator is operable to produce reciprocating first strokes of the rod along the path. A second hydraulic actuator comprises a second cylinder and a ram piston shaped and arranged so as to permit with respect thereto relative movement along the path of the second support means. The ram piston has a diameter substantially greater than the first piston and is movable along the path in reciprocating second strokes substantially shorter than the first strokes.

Abstract: Each column of a press comprises a core rod 2 slidably surrounded by a sleeve 3. The tightening jack 10 associated with the column in question acts on the mobile plate 8 to tighten the mould 11, 12. The upper plate 4 transmits the reaction to the auxiliary jack 5-6 which, bearing on the core 2, applies to the plate 4 a force equal to that developed by the auxiliary jack. In this way the sleeve is theoretically subjected to no effort. The jacks 9, 10 and 5-6 may be supplied in parallel. If the tightening jack 9-10 is not coaxial to the column, one may be content with an approximate solution, or one may use as auxiliary jack a multiple jack in tandem, suitably supplied, or the deformations of the sleeve may be detected and the auxiliary jack controlled so that it cancels them.

Abstract: Am improved press for molding ceramic material which has a base frame on which a first carrier is rigidly mounted and which fixedly supports a stationary punch. A stripper platen is slidably movably supported on said first carrier and is adapted to be reciprocated therein by third piston and cylinder means mounted in said first carrier. The stripper platen includes an annular chamber disposed around the stationary punch for receiving granular ceramic material from a hopper mounted in the base frame. A second carrier is also rigidly mounted in the base frame and supports first and second cylinder and piston means. The first cylinder and piston means serves to support a movable punch which exerts the main molding pressure on the ceramic material when the stationary and movable punch are in the molding position. The second cylinder and piston serve to move the movable punch towards and away from the stationary punch and to exert supplemental pressure on the movable punch during the molding process.

Abstract: An apparatus for closing a mold in an injection-molding operation has a double-acting main piston that is connected to a mold-carrying plate and that move axially in a main cylinder. A rapid-action piston extends into a small-diameter bore in the main piston, and the rear cylinder wall is formed with a large-diameter fill passage connected directly to a sump. A positioning cylinder is fixed on the main cylinder and contains a positioning piston axially fixed on the rapid-action piston and having in the positioning cylinder a rearwardly directed face larger than the face of the rapid-action piston and forming with the positioning cylinder a pressurizable positioning chamber. A passage extends axially through the rapid-action piston from its cylinder to the positioning chamber.

Abstract: An injection molding machine comprises an injection piston-cylinder mechanism including therein an injection piston and a booster piston. The booster piston is provided with a longitudinal through hole through which a pressurized fluid is supplied from an external source into the piston-cylinder mechansim so as to act on the injection piston to fill the mold cavity with molten bath. When the inner pressure of the cylinder chamber between both pistons reaches a predetermined value or the injection piston reaches a predetermined position, a valve assembly which is connected to the cylinder chamber through a conduit is operated so as to drain the pressurized fluid in the cylinder chamber in a controlled manner thereby to advance the booster piston.

Abstract: A method and apparatus is provided for making a composite structural homogeneous resinous article having (a) a smooth, shiny non-cellular or homogeneous relatively thin injection compression molded liner on the outer surface and (b) a cellular relatively thicker injection molded core integral with the molded liner. One extruder is connected by valve controlled passages to a pair of injection devices, each device having an injection chamber. One chamber stores the homogeneous plastic resin and the other chamber stores the foam plastic resin. A first mold assembly having a movable upper mold part and a stationary lower mold part form a cavity, with a gap opening, at a first molding station. The cavity is in communication with the first injection chamber.

Abstract: An improved vulcanizing press for manufacturing tires is disclosed which is constructed such that a molding die assembly is clamped by means of a plurality of hydraulic cylinder units, wherein the respective hydraulic cylinder units are provided with a booster for serving to pressurize hydraulic liquid to actuate a ram slidably contained in a hydraulic chamber and a pilot operated check valve for controlling supply of hydraulic liquid into said hydraulic chamber or discharge of the same therefrom.

Abstract: A hydraulic actuator assembly for a push-type die closing unit of an injection molding machine capable of producing rapid die opening and closing movements with a small volume of pressurized fluid and an elevated die closing pressure in the closed die position, the assembly comprising a central power cylinder with a selectively bypassable power piston and two parallel, diametrally oppositely arranged single-acting travel cylinders. The low-pressure space on the forward side of the power piston is open to the pressure spaces of the two travel cylinders, and the total effective area of these pressure spaces is larger, by a relatively small amount, than the area of the high-pressure space to the rear of the power piston, said small amount determining the fluid volume necessary for the opening travel. A stationary plunger cooperates with a central bore in the rear portion of the power piston rod to produce a small pressure space for the closing travel.

Abstract: In a double-acting hydraulic press: an outer press ram having a cylinder formed therewithin for the piston of an inner press ram, the inner and outer ram cylinders in communication with one another and the rams being subject to a common hydraulic actuating means, each ram carrying a separate and distinct tool at its forward face, and means controllably feeding pressurized hydraulic fluid to an intermediate section of said inner ram cylinder, whereby to control the effective hydraulic force applied to said inner ram and the tool thereof.

Abstract: The apparatus of the present invention includes a stationary assembly and a movable assembly. The stationary assembly is comprised of a stationary platen which has a heat plate, a temperature-controlled sprue bushing and a mold face positioned thereon. The movable assembly is comprised of a movable platen which has a heat plate mounted thereon and a mold face, corresponding to, and adapted to be aligned with, the mold face on the stationary assembly to form a partially open mold cavity. Means are provided to feed a supply of thermosetting molding material through the sprue bushing into the partially open mold cavity. Means are provided to completely close the mold cavity and place the apparatus in a compression stage.

Abstract: There is disclosed an improved molding machine and a system for utilizing said machine, wherein central sources of supply are used to provide the operating requirements for the machine, such as high pressure hydraulic fluid, compressed air, cooling water and electic power. The machine disclosed utilizes a stationary platen and a movable platen, with a novel mold clamping arrangement as an integral part of the movable platen assembly. In this regard, said movable platen includes a pair of relatively movable plate members, with a high pressure diaphragm interposed therebetween. On the rearward most plate member there is mounted latching means for fixing the position of said rearward plate member preparatory to pressurizing of the diaphragm. When pressurized, the diaphragm will force the forward most plate member toward the stationary platen to effect the desired preloading of the mold inserts carried by said platens.

Abstract: A molding machine for die casting, injection molding, and other similar processes, comprises a base shaped to support thereon a two-part die, and a ram for converging and diverging the die halves between open and closed positions. A pair of clamping frames are pivotally mounted on one end of the base, and include a closed border shaped to surround or receive therein side portions of the die halves. The clamping frames are laterally pivoted between a fanned-apart or open position wherein the die can be freely lifted off of the base, and a folded or closed position wherein the frame borders surround the die side portions and capture the same between the ends of the frames. In the closed position, retractable compression columns extend between the die and one end of the frames to positively lock the die halves in the closed position, whereby die separation forces developed during injection of the die are resisted substantially solely by the clamping frames.

Abstract: An injection mold with locking device comprises a fixed backing plate and a fixed mold part plate which are connected to each other by four tie rods. A movable mold part plate is connected to the fixed backing plate through a drive and locking mechanism which is capable of moving the movable mold part plate into a mold position with the fixed mold part plate. A thermal force control apparatus is associated with one or more of the tie rods for changing the temperature of the tie rods and thereby causing the tie rods either to expand or contract. By such expansion or contraction, the exact force applied between the fixed and movable mold part plates can be adjusted to a desired level.

Abstract: A hydraulic actuator assembly for use in the die closing unit of an injection molding machine, the actuator assembly having a large power cylinder and a smaller travel cylinder with a large power piston and a small travel piston on a common piston rod, and bypass channels in the power piston which are openable and closable by means of an annular valve plunger moving on a guide sleeve on the piston rod. The valve plunger and the guide sleeve have three stepped cooperating sliding diameters forming bypass opening and closing plunger pressure spaces. Hydraulic pressure is supplied to the two pressure spaces through bores in the piston rod.

Abstract: A hydraulic press includes long stroke piston cylinder assemblies to drive a movable platen along four pull down power rods between an upper open position and a lower reference position immediately adjacent to and parallel with the stationary platen, a wedge ring clamp mechanism selectively to lock the movable platen to the four pull down power rods at either the upper or lower reference positions, and short stroke piston cylinder assemblies operative reciprocally axially to drive the four pull down power rods when the upper platen is locked thereon to move said locked upper platen between said reference position and a closed position in which the two platens are loaded under high forming pressure.

Abstract: An improved molding apparatus for injection-compression molding thermosetting materials is described. The apparatus comprises a stationary platen assembly, a moveable platen assembly and a feed nozzle assembly.The stationary assembly is comprised of a stationary platen member, a heated plate mounted on the support plate and a plurality of mold faces mounted on the heat plate.The movable assembly is comprised of a moveable platen member, a heated plate mounted thereon and a plurality of mold faces mounted on the heat plate aligned with the mold faces on the stationary assembly.The feed, or injection, nozzle assembly is comprised of a cylindrical nozzle member, having an internal temperature controlling means, and a plurality of feed outlets positioned on the periphery.

Abstract: In a molding press having fixed and movable platens for mounting mold halves, the movable platen is connected through thrust rods and a thrust plate to the movable component of an hydraulic piston-cylinder platen drive unit the fixed component of which is attached to a fixed base. A high pressure piston-cylinder mold clamping unit of the pancake type interengages the movable platen and a pancake cylinder support plate mounted for movement along the thrust rods and arranged for abutment by the thrust plate. The pancake cylinder support plate and fixed base are joined together by toggle joints operated by a piston-cylinder locking unit supported pivotally on arms extending pivotally from the pancake cylinder support plate and fixed base. The drive unit thus is arranged in parallel with the series arrangement of the toggle joints and mold clamping unit.

Abstract: A fluid-operated press comprises a crosshead, a bead, four upstanding posts each extending vertically between each corner portion of the crosshead and each corner portion of the bead, and a slider disposed between the crosshead and the bead and slidably fitted on the posts to be slidable along the latter. An upright wall structure located outside the slider and the posts is clamped between the crosshead and the bead to enhance rigidity of the frame structure of the press. The upright wall structure has a wall portion surrounding at least that portion of the peripheral surface of each post which, as viewed in cross-section of the press through the upright wall structure, is positioned between two lines obtained by extending two adjacent sides of a rectangle which is formed by connecting the center points of the four posts.

Abstract: A mold-closing device for an injection-molding machine has a main piston connected to the mold-carrying plate of a movable mold half and is provided with a pressure-multiplying piston which closes a passage between sides of the main piston to render effective the differential action of the multiplier piston. The multiplier piston can be shifted prior to the main piston by a time-delay device in the pressure lines and/or by a mechanical element.

Abstract: A pressing machine arrangement, comprising at least two dies defining a molding cavity is described.The main feature of this machine is to comprise means for adjusting the thrust pressure exerted at least on one of the said dies (22, 255), substantially in every region of the said dies, in order to maintain substantially mating, during the stage of maximum thrust, the contours of the said dies (22, 7, 255, 332) which define the said molding cavity, by means of an analogous deformation for the said two dies. Said means comprise a cylinder (77, 213) whose head (76, 216) acting into the said dies has a relatively reduced thickness, so as to allow its deformation.

Abstract: Mould closing, clamping and opening means for the split mould of a pressure moulding machine comprises a pair of elongated arms each pivotally attached to the moving platen of the machine at one end and free at the other end, and extending lengthwise between the moving platen and a hydraulic rear clamping platen. During a mould operation the free ends of the arms engage the rear clamping platen so as to act as struts between the rear clamping platen and the moving platen during a mould clamping operation, but during a mould opening operation the arms are swung by an hydraulic cylinder to a position in which they register with openings in the rear clamping platen so that the arms may pass rearwardly through the openings as the mould opens.

Abstract: An injection molding machine having a dual tonnage traversing cylinder whereby extended stroke mold breakaway force may be exerted by the traversing cylinder unit before it begins its higher speed traversing movement to completely open the mold. The traversing cylinder comprises a normal length piston received within the cylinder barrel and bolted at one end to the moveable platen. The effective working area of the pressure face for this piston during the retraction stroke is such that low force, high speed retraction of the mold section connected to the moveable platen may be achieved. Also disposed within the barrel is a breakaway piston, which may be annular in shape and disposed concentrically with respect to the fast traverse piston and positioned such that it will abut an annular shoulder on the fast traverse piston throughout the retraction stroke of the breakaway piston.

Abstract: A mechanical press has a self-adjusting device for automatically setting the position of the mould in the correct position with respect to the stroke of the pressram. The device is located between a fixed platen and a mould carrier and comprises a cylinder having at one end a stiffly resilient plug which normally covers a valve port in the cylinder; a volume of liquid is located between a piston in the cylinder and the plug. If the mould is incorrectly set for the ram stroke, the pressure generated in the liquid so compresses the plug to expose the port for release of sufficient liquid to reposition the mould.

Abstract: A thrust member on column secured to a movable platen of an injection-molding machine, surrounded by a mounting frame with laterally withdrawable shutters which enter behind the thrust member in the terminal phase of a mold-closing stroke for transmitting to the thrust member a supplemental clamping force, is linked with a hydraulically actuated plunger or driving piston via a lost-motion coupling. The clamping force is supplied through one or more annular pistons received in respective cylinder chambers of a stationary housing linked via tie rods with a fixed platen. Upon the release of the clamping force, a counter-vailing hydraulic force is developed between the column and the driving piston, whose forward displacement is limited by a fixed abutment, to break open the mold with a larger hydraulic force.

Abstract: A mold closing and locking device is disclosed, including a fixed mold carrier plate, a stationary end plate, a movable mold carrier plate displaceable between the fixed mold carrier plate and the stationary end plate on support shafts through the action of a piston-cylinder unit, an adjustable distance-determining member extending between the piston-cylinder unit and the movable mold carrier plate, a pressure plate carried on a swivel arm for movement into and out of engagement between said piston-cylinder unit and said distance determining member, with the swivel arm being attached to a pivot bearing mounted on one of the aforesaid support shafts, with the pressure plate having a limited displacement range against spring tension in a direction parallel to the movement of the movable mold carrier plate, and with the swivel arm being movable by means of a pressurized pivot drive supported on another of the support shafts.

Abstract: A method and apparatus for accommodating various sizes of molding die inserts in an injection molding machine using a pair of injection die insert support frames to hold either injection molding die inserts fitting directly into corresponding recesses in confronting faces of the die insert support frames or second injection molding die inserts combined with respective injection die insert adaptors fitting into the recesses in the die insert support frames. An adjustable stop for the confronting faces of the die supports is provided in a confronting face of one of the die insert support frames to maintain a uniform parting line between the die insert support frames and the die inserts by providing a selectively elevatable contact surface above the parting line facing surface of the one die insert support frame.

Abstract: A thermoforming machine having opposed mold platens includes a linkage system driven in cyclic movement by a single rotary cam to cyclically shift the platens between their open and closed position. The cam is driven by a variable speed motor which is controlled in a manner such that the rotary speed of the cam during different portions of a cam revolution may be set to a speed which is different than the rotary speed of the cam during other portions of each revolution. By adjusting the speed differential or by adjusting the angular extent of that portion of a revolution of the cam over which the different speed is maintained the time duration of any chosen portion of the cycle may be adjusted independently of the time duration of other portions of the cycle. The platens are mounted for reciprocatory movement upon a three-post frame.

Abstract: A mold closing device of an injection molding machine is disclosed which is reliable in operation and simple in structure. Both the opening and closing of the valve for hydraulic oil passage can be attained in the mold closing device of the invention in which two valve controlling oil chambers are formed in the boundary between the valve member and a quick shifting ram. One of the above oil chambers is connected to a forward cylinder and the other, to a return cylinder, thereby attaining the opening and closing of valve by hydraulic pressure in synchronism with the movement of a mold closing piston which is attached to the quick shifting ram.

Abstract: A mechanical press includes a plurality of cylinders to provide different fluid pressures to a lower mold against an upper mold to mold plastic parts. A pair of accumulators sequentially apply a low pressure to the cylinders for a predetermined time during the initial heating period and a high pressure for a predetermined time during the final molding period. A control valve controls the rate at which the high pressure is applied.

Abstract: Closing unit for an injection moulding machine or transfer moulding press with a frame, a first tool carrier rigidly connected therewith, a second displaceable tool carrier and hydraulic displacing devices, which are eccentrically arranged with respect to the tool carriers and of which each has a hollow cylinder fastened to the frame and a piston which is displaceably guided therein and of which each is provided on one side with a first shaft and on the other side with a second shaft. The first shafts are arranged such that they are drawn into the hollow cylinders when the tool carriers are brought nearer to each other, and wherein one each of the two shafts of the pistons is connected rigid with the second tool carrier. According to the invention, at least two pistons are provided, the first shaft of which has a smaller diameter than its second shaft, and there are also provided at least two pistons, the first shaft of which displays a greater diameter than its second shaft.

Abstract: A compact die closing unit for injection molding machines with four pull-type hydraulic linear actuators and an oversize multi-plate injection molding whose stationary die plates engage the piston rods with centering bores, thereby extending the piston rod support in the die separation plane, and whose movable die plates similarly engage the piston rods with centering bores, so as to be carried by the piston rods directly, without the need for a movable die carrier plate and a stationary cantilever frame supporting the latter. The hydraulic supply lines for the power piston bypass control valve are arranged in the auxiliary cylinders.

Abstract: In a pressure moulding machine, particularly a die casting machine, detection of locking together of the die parts by the applied pressure is effected by detecting the resulting mechanical stretch in the machine frame; the die parts are opened and closed together by an air motor associated with a hydraulic motor that damps the opening and closing movement of the dies, the die parts being locked together by the hydraulic motor; full closing of the die parts is determined by applying pressurized air to bores therein and to a controlling pressure switch, the pressure switch not being operable if air is leaking from the bores.

Abstract: A toggle press having a lower platen assembly constructed to provide a convenient working level for the platen in its open position. The fixed axis of the toggle linkage is mounted immediately adjacent to the ground and the actuator for the toggle linkage is inclined in the direction downwardly progressing away from the toggle actuating axis. The press is constructed with a beam which includes a base plate, this base plate having an extension upon which the fixed pivot of the toggle linkage is mounted, below the neutral axis of the beam. Additional structural features enable compensating deflection and self-alignment of the toggle bearing under load.

Abstract: A press for moulding plastic materials for the manufacture of gramophone disc records or like flat parts comprises a fixed press platen carrying a first mould element, a movable press platen guided along columns fast with the fixed platen and a movable intermediate platen carrying a second mould element. A mechanical device is provided to urge the movable press platen to the fixed press platen. A fluid pressure is supplied between coacting cylinder and piston provided respectively in the movable platens. The intermediate platen is supported and guided by the movable platen without any contact between this intermediate platen and the columns.