DEVICE FOR METALLIC MOLD ON MOLDING MACHINE

Abstract: When one of a set of two metallic molds swingingly turns in association with the mold-opening motion on opening of the set of molds and then is kept turned sideways, the face of said mold is directed outward to facilitate insertion of an insert into the mold or take out of a molded product therefrom and permit mold face monitoring with ITV. A movable mold (11) is kept just opposite to a stationary mold (2) when the molds are closed, however, when the molds are opened, a pinion (12) is driven to turn by a rack (14) lowering in assocation with the mold opening action and a turning block (7) swingingly turns integrally with the movable mold (11), and, when mold opening is completed, the turning block (7) is kept turned sideways and the mold face is directed outward, whereby a molded product pushed by the protruding pins (18) drops by its own weight.

Description: TECHNICAL FIELD This invention relates to a mold device in an injection molding machine or the like for molding synthetic resin material or the like, and particularly to a mold device for revolving and pivoting a mold when the mold is opened making use of mold opening and closing operation according to the preamble of independent claims 1 and 7. TECHNICAL BACKGROUNDS In the past, in the mold device in an injection molding machine or the like, when a molded article after molding is removed from the mold, a kind of industrial robot called a clamp is moved into a space of the opened mold, whereby the molded article is held by the robot which retreats from the mold space, and the molded article is recovered at a predetermined recovery location. More specifically, the molded article is removed by a series of steps of operations which include mold opening, entry of the clamp, holding of the molded article by the clamp, retreat of the clamp, release of the molded article from the clamp, and recovery of the molded article. In the above-described prior art, the removal of the molded article is carried out using a kind of industrial robot called a clamp. Accordingly, a space for installation of the robot and a space for operation thereof are required. The prior art thus has problems such that the whole device becomes large-sized, and that because of complicated and high-degree operation of the robot, the whole device also becomes complicated and high-degree accordingly, inevitably resulting in an increase in equipment cost. To solve the above-mentioned problems is thus an object of the invention. In US-A-4699584, there is described a molding machine including two press plattens on which are mounted the two parts of a mold. The upper mold part is carried on an arm pivoted to the upper platten, the arm being coupled by a link to the lower platten, whereby movement of the lower platten towards and away from the upper platten gives rise to corresponding pivoting movement in the upper mold. This arrangement has the problem that it is not possible to impart relative linear sliding movement to the two mold parts during the final stage of mold closing, or during the initial stage of mold opening. With high-pressure injection molds, it is necessary to ensure accurate alignment between the mold parts, and this is achieved by providing projecting pins on one part, which are received in bores in the other part; the provision of such pins requires precision linear relative sliding movement between the two parts for as long as the pins are received in the respective bores. In view of problems discussed above of all of the known prior art, including the relatively large size, complication and higher cost, caused by a space restriction placed on the construction of the mold device of an injection molding machine, the present invention provides either the fixed mold or the movable mold to be relatively opened and closed together with a turning and pivoting action through a predetermined angle, by taking advantage of the mold opening and closing operation. In one form, the present invention provides a mold device for a molding machine, comprising: a fixed retainer plate supporting a fixed mold; a movable retainer plate supporting a movable mold co-operable with the fixed mold to define a mold cavity, a clamping cylinder being arranged to move the movable retainer plate towards and away from the fixed retainer plate thereby to close and open the mold cavity; a revolutionary block mounted on the movable retainer plate and supporting the associated movable mold; and operating means acting on the revolutionary block and coupled to a fixed part of the molding machine so as to effect rotation of the revolutionary block during movable retainer plate movement; characterised in that the operating means is arranged not to effect rotation of the revolutionary block during a first stage of movable retainer plate movement when the movable mold is in the vicinity of the fixed mold, the operating means automatically effecting rotation of the revolutionary block during a second stage of the movement of the movable retainer plate when the movable mold has moved away from the fixed mold. In an alternative form, the present invention provides a mold device for a molding machine, comprising: a fixed retainer plate supporting a fixed mold; a movable retainer plate supporting a movable mold co-operable with the fixed mold to define a mold cavity, a clamping cylinder being arranged to move the movable retainer plate towards and away from the fixed retainer plate thereby to close and open the mold cavity; a revolutionary block mounted on the fixed retainer plate and supporting the associated fixed mold; and operating means acting on the revolutionary block and coupled to the movable retainer plate so as to effect rotation of the revolutionary block during movable retainer plate movement; characterised in that the operating means is arranged not to effect rotation of the revolutionary block during a first stage of movable retainer plate movement when the movable mold is in the vicinity of the fixed mold, the operating means automatically effecting rotation of the revolutionary block during a second stage of the movement of the movable retainer plate when the movable mold has moved away from the fixed mold. It will be appreciated that the two forms of the invention as described above are essentially the same, the difference being that in the first form the movable mold is supported in a rotatable manner, for rotation with respect to the fixed mold, whereas in the second form the fixed (i.e. non-sliding) mold is supported in a rotatable manner, for rotation with respect to the movable mold as the latter moves towards and away from the fixed mold. Both forms of this invention are operated as follows. When, after molding, the clamping cylinder is withdrawn to move the movable mold away from the fixed mold to open the mold cavity, initially only relative sliding movement occurs, but then the revolutionary block is turned and pivoted by the operating means. By the completion of mold opening, the revolutionary block has been turned through a predetermined angle. Either the fixed mold or the movable mold (depending upon the actual arrangement) mounted on the revolutionary block is turned and pivoted through a predetermined angle to tilt the mold surface outside the molding space, so that the molded article may be disengaged and ejected from the mold, to fall under gravity for example into a recovery box or the like via a suitable chute. Further details of the invention are defined in the features of the dependent claims. BRIEF DESCRIPTION OF THE DRAWINGS All the accompanying figures show embodiments of the invention Fig. 1 is a perspective view of a first embodiment. Fig. 2 is a perspective view showing essential parts of the first embodiment. Figs 3 to 5 are views for explaining the operation of the first embodiment. Fig. 6 is a side view partly sectioned of a second embodiment. Figs. 7 to 9 are views for explaining the operation of a third embodiment. Figs. 10 to 12 are views for explaining the operation of a fourth embodiment. Figs. 13 and 14 are views for explaining the operation of a fifth embodiment. Fig. 15 is a partial view of another embodiment. BEST IMPLEMENTATION OF THE INVENTION To disclose the best implementation of the invention, a first embodiment of this invention will be described hereinbelow with reference to Figs. 1 to 5. Referring to Fig. 1 and Figs. 3 to 5, a fixed mold 2 is mounted on an upper fixed retainer plate 1 (not shown in Fig. 1), whereas a movable retainer plate 5 is provided on a clamping piston 4 of a clamping cylinder 3. A block supporting plate 6 is detachably secured onto the movable retainer plate 5, and a revolutionary block 7 is supported revolvably and pivotally about a horizontal shaft on the block supporting plate 6. That is, a horizontal rotary shaft 8 of the revolutionary block 7 is supported on the block supporting plate 6 by means of a bearing 9 whereby the revolutionary block 7 can be revolved and pivoted about the horizontal shaft. Preferably, the horizontal rotary shaft 8 is aligned with the pressure receiving center line of the clamping force. As will be apparent from Fig. 2, a mounting table 10 is fixedly mounted on the revolutionary block 7 so that a peripheral edge portion of the table 10 is projected flangewise outwardly from the upper surface of the block 7, and a movable mold 11 can be mounted detachably on the table1 (Fig. 1 and Figs. 3 to 5) . These block supporting plate 6, revolutionary block 7 and mounting table 10 are formed into a unit to constitute a revolutional mold supporting unit. A pinion 12 is slipped over one end of the rotary shaft 8 of the revolutionary block 7. The pinion 12 is meshed with a rack 14 formed on a vertically extending operating rod 13 which is fixedly secured to a fixing menber with respect to the ground, that is, to the clamping cylinder 3 in this embodiment. In this case, the operating rod 13 extends through a guide hole 15 bored in the block supporting plate 6 and extends upwardly from the clamping cylinder 3. The operating rod 13 is formed at its base with an external thread, and two adjusting nuts 13a and 13b engaged with the external thread hold a flange 3a integral with the cylinder 3 whereby the operating rod 13 is fixed adjustably in its upper and lower locations to the clamping cylinder 3. These operating rod 13, rack 14 and pinion 12 constitute revolutionary means for revolving the revolutionary block 7. As will be apparent from Figs. 3 to 5, a stopper 16 is protruded on the block supporting plate 6 so that when the revolutionary block 7 is revolved and pivoted and then returns to a horizontal position, the top surface of the stopper 16 comes into contact with the block 7, that is, with the lower surface of the peripheral edge portion protruded flangewise of the mounting table 10 to impede a further revolutionary and pivotal movement of the block 7 (Fig. 3). The lower surface of the revolutionary block 7 is semicircular as viewed in side so as to allow a free revolutionary and pivotal movement thereof. It is noted in this case that the shape of the lower surface of the revolutionary block 7 is not limited to the aforesaid semicircular shape but other shapes can be employed as long as the block 7 does not interfere with other members, particularly the block supporting plate 6 when the block 7 is revolved. The revolutionary block 7 is interiorly provided with an ejection cylinder (not shown) capable of being supplied with working oil via a flexible working oil pipe for ejecting a molded article, and an ejection pin 18 connected to a piston thereof extends through the mounting table 10, said pin 18 extending so as to be moved in and out of the bottom surface of a carved space (not shown) in the movable mold 11. A main stay indicated at 17 extends through the movable retainer plate 5 and the block supporting plate 6 and is connected to the upper fixed retainer plate 1 to support the latter. With the above-described arrangement, at a clamping stage shown in Fig. 3, the lower surface of the flange-like peripheral edge portion of the mounting table 10 for the revolutionary block 7 comes into contact with the upper surface of the stopper 16 to impede a further rotation of the revolutionary block 7 to allow the block 7 to be in a horizontal position. When the mold is opened from the aforesaid positon of the clamping stage, the clamping piston 4 of the clamping cylinder 3 retreats and moves down, and the revolutionary block 7 also begins to move down along therewith. In the early stage, however, the pinion 12 is in contact with a plane portion 14a (a portion not formed with a rack) at the extreme end of the fixed operating rod 13, and the pinion 12 thus slides without rotation. Accordingly, the revolutionary block 7 also moves down some distance while maintaining its horizontal position without revolutionary and pivotal movement. When the clamping piston 4 further continues to move down, the pinion 12 is rotatively driven by the rack 14 of the fixed operating rod 13, and the revolutionary block 7 revolves and pivotally moves clockwise as shown in Fig. 4. When the clamping cylinder 3 further retreats and moves down and the revolutionary block 7 further retreats and moves down, the revolutionary block 7 further revolves and pivotally moves and the movable mold 11 falls and inclines till the mold 11 substantially turns sideways as shown in Fig. 5. When, under the turned sideways state as described above, the ejection cylinder is supplied with working oil and the ejection pin 18 is protruded toward the bottom surface of the carved space in the movable mold 11, then, an ejected molded article is disengaged from the movable mold 11 and allowed to fall by gravity and recovered into a recovery box or the like via the chute 19. If the peripheral edge portion of the mounting table 10 is placed in contact with the block supporting plate 6 at the turned sideways position of the revolutionary block 7, then, the stabilized position defining operation can be ensured. Further, by manipulating the adjusting nuts 13b and 13b, longitudinal locations of the operating rod 13 with respect to the clamping cylinder 3 can be adjusted. Moreover, the umber of teeth of the pinion 12 and the amount of vertical movement of the revolutionary block 7 can be controlled to thereby define suitably the revolutionary angle of the movable mold 11, that is, the falling and inclining angle of the revolutionary block 7. In the mold closing stage, the operation reversed to that as described above is ensured. The revolutionary block 7 revolves and pivotally moves till the lower surface of the peripheral edge portion of the mounting table 10 of the revolutionary block 7 comes into contact with the upper surface of the stopper 16, as shown in Fig. 3. At that stage, the engagement of the pinion 12 with the rack 14 is released so that the pinion 12 faces the plane portion 14a, and therefore, the revolutionary block 7 stops to revolve and pivotally move. The block 7 moves upward while maintaining the horizonatal position thereof, and accordingly, the movable mold 11 is opposed to the fixed mold 2 to complete the mold closing operation. Thereafter, the clamping operation is carried out while maintaining the horizontal position of the movable mold 11. While in the above-described embodiment, it is designed so that the stopper 16 comes into contact with the lower surface of the flange-like peripheral edge portion of the mounting table 10, it is to be noted that the stopper 16 may come into contact with a part of the revolutionary block 7 itself. Moreover, while in the above-described embodiment, the vertical operating rod 13 has been secured to the clamping cylinder 3, it is to be noted that the rod 13 may be secured to the other suitable stationary member. Fig. 6 shows a second embodiment in respect of the best implementation of the invention. In the above-described first embodiment, the movable mold 11 is mounted on the revolutionary block 7 and is revolved and pivotally moved through a predetermined angle together with the revolutionary block 7. In the second embodiment, however, the fixed mold 2 is mounted on the revolutionary block 7. More specifically, the revolutionary block 7 is mounted on the fixed retainer plate 1, which is mounted on the bed 20 fixed to the ground, through the block supporting plate 6, and the fixed mold 2 is mounted on the the block 7. The movable mold 11 is mounted on the upper movable retainer plate 5, the movable mold 11 being moved up and down by a tie bar 21 and cross rods 17 for main stays secured to the piston 4 of the clamping cylinder 3 so as to be opened and closed. In this embodiment, the operating rod 13 formed with the rack 14 has its upper end fixedly secured to the movable retainer plate 5 by means of the adjusting nuts 13a and 13b and extends downwardly, said operating rod 13 further extending downwardly through a guide hole 15 of the fixed retainer plate 1. In this case, the plane portion 14a of the operating rod 13 which is not formed with a rack is located on the root side, that is, on the upper side of the operating rod 13. The operation of this embodiment will be described below. At the illustrated clamping stage, the pinion 12 of the revolutionary block 7 is in contact with the plane portion 14a of the operating rod 13 and is not meshed with the rack 14. When the upper movable retainer plate 5 is driven by the clamping cylinder 3 and moved upward to open the movable mold 11, the operating rod 13 also integrally moves upward. At this time, however, the rack 14 is not meshed with the pinion 12, and therefore, the revolutionary block 7 is not revolved till they are meshed with each other, and the mold is opened while maintaining the position in which the fixed mold 2 faces the movable mold 11. Thereafter, when the rack 14 comes into engagement with the pinion 12, the revolutionary block 7 revolves as the movable mold 5 moves upward. The thereafter operation is similar to that described in the aforementioned first embodiment. To disclose the best implementation of the invention, another embodiment will be described hereinbelow with reference to Figs. 7, 8 and 9. In the first and second embodiments, the operating rod 13 which constitutes the revolutionary and pivotal means for revolving and pivotally moving the revolutionary block 7 is fixedly secured to the mounting member (the clamping cylinder 3 in the first embodiment, and the movable retainer plate 5 in the second embodiment). This embodiment, however, is different from the first and second embodiments in that the operating rod 13 is mounted on the mounting menber so as to allow a movement thereof in the mold opening and closing direction by a predetermined distance. That is, in this embodiment, a follower cylinder 22 is fixed to the clamping cylinder 3 as a mounting member, and a piston 24 formed at the extreme end of a lower end portion 23 of the operating rod 13 is slidably inserted into the follower cylinder 22. The follower cylinder 22 is provided to allow only the stroke for a predetermined distance of the operating rod 13 which moves up and down along with the piston 24, and a further downward movement thereof is interrupted by a stopper 25. In the case of this embodiment, since it is unnecessary for one corresponding to the plane portion 14a of the operating rod 13 in the first and second embodiments to be provided, the rack 14 is in the state in which it is always meshed with the pinion 12. The operation of this embodiment will be described below. At the clamping stage shown in Fig. 7, the operating rod 13 is raised upward, and the piston 24 is also at an upper location in the cylinder 22. At this operating stage, a valve is controlled so that working oil may freely flow into and out of an upper chamber (a rod chamber) 22a and a lower chamber (a head chamber) of the cylinder 22. This operating stage is shifted to a mold opening stage. When the movable mold 11 is moved down by the clamping cylinder 3, the operating rod 13 in which the rack 14 is meshed with the pinion 12 also integrally starts its descending operation since the piston 24 can be freely moved up and down in the cylinder 22. The revolutionary block 7 is not revolved, and the movable mold 11 moves down in a position in which the former is opposed to the fixed mold 1. When the mold opening operation proceeds through a predetermined distance, the stopper 25 of the operating rod 13 comes into contact with the upper surface of the clamping cylinder 3 as shown in Fig. 8, and further descending of the operating rod 13 is interrupted. After this operating stage, when the mold opening further proceeds, the revolutionary block 7 begins to be revolved and pivotally moved around the horizontal rotary shaft 8 by the action of the rack 14 and the pinion 12 of the operating rod 13. In this case, since the movable mold 11 has already been parted away from the fixed mold 2 by a predetermined distance, the operation of the mold 2 does not interfere with that of the mold 11, and the revolutionary and pivotal movement of the revolutionary block 7 continues till the movable mold 11 reaches the turned sideways position and stops thereat as shown in Fig. 9. Next, the mold closing operation will be described. At the stage in which the revolutionary block 7 and the movable mold 11 are terned sideways as shown in Fig. 9, the follower cylinder 22 is controlled by a valve so as to impede a flow of wording oil into and out of the upper chamber 22a and the lower chamber 22b, and the oprating rod 13 is locked at that location. Meanwhile, the movable retainer plate 5 moves upward to iniiate the mold closing operation. In this case, since the operating rod 13 is not moved upward by the locking motion of the follower cylinder 22, the revolutionary block 7 is revolved by the action of the rack 14 and the pinion 12. When the movable mold 11 returns to the horizontal position at which the mold 11 is located below the fixed mold 2 to be opposed to the same, the revolutionary block 7 is settled in its return horizontal position by the stopper 16. When, at this operating stage, the follower cylinder 22 is operated by a valve to release the locking motion of working oil and render a flow of working oil into and out of the cylinder 22 free, the operating rod 13 integrally moves upward as the movable retainer plate 5 moves upward to complete the mold closing operation of hte movable mold 11 with respect to the fixed mold 2. To disclose the best implementation of the invention, still another embodiment (a fourth embodiment) is shown in Figs. 10, 11 and 12, in which the revolutionary and pivotal means for revolving and pivotally moving the revolutionary block 7 is different from that shown in the aforementioned first to third embodiments. In these figures, a revolutionary arm 27 is secured to the revolutionary block 7, said arm 27 being formed with a slot 28 bored therein, and a pin 29 protruded on the operating rod 13 is slidably inserted into the slot 28. The revolutionary arm 27 is coupled relatively unrotatably with the rotary shaft 8 by means of a mechanism in which the arm 27 is brought into engagement with a prismatic portion 8a formed at an end of the rotary shaft 8 of the revolutionary block 7. Also, in this embodiment, the follower cylinder 22 is provided at the end of the operating rod 13 in the same way as the third embodiment shown in Figs. 7 to 9. However, since the valve control during the mold opening and closing operation is similar to the case of the third embodiment, the explanation thereof is omittd. When the mold opening operation starts from the closed state shown in Fig. 10, the operating rod 13 moves down along with the revolutionary block 7, and the revolutionary bolck 7 is not revolved but the movable mold 11 moves down in the horizontal position while being opposed to the fixed mold 2 as shown in Fig. 11. When the operation rod 13 moves to a location as shown in Fig. 11, a further downward movement thereof is interrupted by the stopper 25. As the movable retainer plate 5 and the revolutionary block 7 further move down, the pin 29 is slidably moved along the slot 28 to cause the revolutionary arm 27 to be rotated. Therefore, as shown in Fig. 12, the revolutionary block 7 revolves and pivotally moves, and the movable mold 11 reaches the turned sideways position so that the mold surface faces outside the operating space. The valve control of the follower cylinder 22 during the mold closing operation is also similar to the case of the third embodiment shown in Figs. 7 to 9. It will be easily understood that at the early stage of the mold closing operation, the revolutionary block 7 is revolved and pivotally moved, and after the movable mold 11 has been opposed to the fixed mold 2, the operating rod 13 also moves upward along with the revolutionary block 7 to complete the mold closing operation. A fifth embodiment in respect of the best implementation of the invention is shown in Fig. 13 and 14. This embodiment is different from the fourth embodiment shown in Figs. 10 to 12 in that a linking rod is used as connection means between the revolutionary arm 27 and the operating rod 13. In the figures, the revolutionary arm 27 of the revolutionary block 7 and the operating rod 13 are connected by means of a linking rod 30. More specifically, the linking rod 30 is pivotally mounted on the operating rod 13 by means of the pin 31, and the linking rod 30 is also pivotally mounted on the revolutionary arm 27 by means of a pin 32. The revolutionary arm 27 and the linking rod 30 constitute a link mechanism. In the early stage of the mold closing operation, the operating rod 13 moves down along with the revolutionary block 7, and therefore, a positional relationship between the revolutionary arm 27 and the linking rod 30 linked thereto remains unchanged. When a downward movement of the operatig rod 13 is soon interrupted by the stopper 25, the revolutionary arm 27 is rotatively driven clockwise by the linking rod 30 so that as shown in Fig. 14, the revolutionary block 7 revolves and pivotally moves, and the movable mold 11 thus reaches the turned sideways position. The movement of the follower cylinder 22 during the mold closing operation is also totally similar to the cases of the third and fourthe embodiments already described. In the third, fourth and fifith embodiments described in connection with Figs. 7 to 9, Figs. 10 to 12 and Figs. 13 and 14 respectively, the lower movable mold 11 is revolved and pivotally moved while being opened and closed with respect to the upper fixed mold 2. It is, however, to be noted of course that in the same way as the second embodiment shown in Fig. 6, the lower fixed mold 2 may be revolved and pivotally moved by the mold opening and closing operation of the upper movable mold 11. It is natural in this case that as shown in Fig. 15, the follower cylinder 22 is mounted on the upper retainer plate 5, and the stopper 25 is allowed to be provided on the opposite side of the cylinder 22 over the upper movable retainer plate 5. Furthermore, although in any of these embodiments described above, a description has been made of a vertical type molding machine, it is obvious that the present invention can be applided to a lateral type molding machine. As for the revolutionary direction of the revolutionary block in the lateral type molding machine, there can be employed a mode for implementation in which the block is revolved about a vertical shaft in a horizontal surface to direct the mold surface toward an operator, and a mode for implementation in which the block is revolved about a horizontal shaft in a vertical surface to direct the mold surface douwnwardly. In the case of the latter mode in which the mold surface is directed downwardly, scavenging undesiable inserts in a carved space in the mold by means of gravity and swishing waste liquid off the carved space in the mold can be accomplished, thus resulting in an incidental advantage that the mold surface is easily cleaned. INDUSTRIAL USABILITY As described above, according to the present invention, a revolutionary block is revolvably and pivotally supported on a block supporting plate mounted on a retainer plate, either of a fixed mold or a movable mold is mounted on the revolutionary block, and an operating rod is provided to revolve the revolutionary block in respose to the opening and closing operation of the movable mold. With this arrangement, in the mold opening operation after molding, one mold is revolved and pivotally moved to cause the mold surface to face outside the operating space, where a molded article ejected and disengaged from the mold falls by gravity. Accordingly, an industrial robot for removing a molded article is not required so that the whole apparatus is prevented from being large-sized. In addition, since the mold opening and closing operation itself is utilized to pivotally move the revolutionary block, a separate driving means is not additionally required, this, therefore, ensuring industrial usability in that the structure of apparatus is extremely simple and the cost is considerably reduced. Moreover, the revolutionary and pivotal movement of the revolutionary block appears just during a period of mold opening operation, this, therefore, ensuring industrial usability in that a period of removing operation for molded articles overlaps with the period of mold opening operation, and as a result, the overall operating period is shortened. Furthermore, since the mold surface faces outside the operating space by means of the revolutionary and pivotal movement of the revolutionary block, automatic monitoring of the carved space in the mold by an industrial television set (ITV), which is difficult to be installed in the operating space, becomes very easy by the installation of the ITV out of the operating space and in addition, inserting inserts into the carved space in the mold is also easily attained. Particularly in the case the present device is applied to the vertical type molding machine, the mold in an open state can ben inclined at a suitable angle of inclination sideways to ensure a position facing to an operator, in which case, an insert inserting operation is particularly advantageous. By the additional installation of a follower cylinder on an operating rod, the operating rod can be moved by a predetermined distance during the mold opening and closing operation, and therefore, at the early stage of mold opening operation, the operating rod is moved in assoiation with the opening operation of the movable mold, and the revolutionary block is thus not revolved. Accordingly, the movable mold and the fixed mold are maintained at the position opposed to each other till they are parted by a considerably large predetermined distance, and thereafter, the revolutionary block begins to revolve and pivot. Therefore, both of the molds are not interfered or run against each other during the revolutionary and pivotal movement. In the mold closing operation, closure is attained after both of the molds have been accurately opposed to each other, and thereafter, clamping is effected. Therefore, an unnatural force is not applied to the molds. Furtheremore, since the revolutionary mold support unit is of a complete separate unit, it is not only applicable to various mold devices but also the revolutionary direction of the mold can be freely selected. In addition, by the protrusion of a stopper in contact with the revolutionary block, the movable mold can be accurately opposed to the fixed mold at the termination stage of mold closing operation. Therefore, there is a further advantage in that the revolutionary block itself effectively functions as a member for stably transmitting a high clamping pressure to the fixed mold at the succeeding clamping stage.

Claims: A mold device for a molding machine, comprising: a fixed retainer plate (1) supporting a fixed mold (2); a movable retainer plate (5) supporting a movable mold (11) co-operable with the fixed mold (2) to define a mold cavity, a clamping cylinder (3) being arranged to move the movable retainer plate (5) towards and away from the fixed retainer plate (1) thereby to close and open the mold cavity; a revolutionary block (7) mounted on the movable retainer plate (5) and supporting the associated movable mold (11); and operating means (12,13; 13,27) acting on the revolutionary block (7) and coupled to a fixed part of the molding machine so as to effect rotation of the revolutionary block (7) during movable retainer plate (5) movement; characterised in that the operating means (12,13; 13,27) is arranged (14a; 22,24) not to effect rotation of the revolutionary block (7) during a first stage of movable retainer plate (5) movement when the movable mold (11) is in the vicinity of the fixed mold (2), the operating means automatically effecting rotation of the revolutionary block (7) during a second stage of the movement of the movable retainer plate (5) when the movable mold (11) has moved away from the fixed mold (2). A mold device as claimed in claim 1, wherein the operating means includes: (a) an operating rod (13) secured at one end to a fixed part of the molding machine; (b) a plane portion (14a) formed at the other end of the operating rod (13); (c) a rack (14) formed on the operating rod adjacent said plane portion (14a); and (d) a pinion (12) furnished on a shaft (8) mounting the revolutionary block (7) on the movable retainer plate (5), which pinion (12) meshes with said rack (14) during said second stage of movement, and overlies the plane portion (14a) during said first stage of movement. A mold device as claimed in claim 1, wherein the operating means comprises: (a) a follower piston-and-cylinder combination (22,24) mounted on a fixed part of the molding machine; (b) an operating rod (13) connected to the piston-and-cylinder combination (22,24) for axial movement thereby; (c) a rack (14) formed on the operating rod (13); and (d) a pinion (12) furnished on a shaft (8) mounting the revolutionary block (7) on the movable retainer plate (5), which pinion (12) meshes with the rack (14), whereby rotation of the pinion (12) is prevented during said first stage of movement by driving the piston-and-cylinder combination (22,24) to move the operating rod (13) at the same rate as the movement of the movable retainer plate (5). A mold device as claimed in claim 3, wherein the piston-and-cylinder combination (22,24) is co-axial with the operating rod (13), the piston (24) being provided on rod (13). A mold device as claimed in claim 1, wherein the operating means comprises: (a) a follower piston-and-cylinder combination (22,24) mounted on a fixed part of the molding machine; (b) an operating rod (13) connected to the piston-and-cylinder combination (22,24) for axial movement thereby; (c) a crank arm (27) mounted on a shaft (8) mounting the revolutionary block (7) on the movable retainer plate and coupled to the operating rod (13), whereby rotation of the shaft (8) is prevented during said first stage of movement by driving the piston-and-cylinder combination (22,24) to move the operating rod (13) at the same rate as the movement of the movable retainer plate (5). A mold device as claimed in claim 5, wherein the piston-and-cylinder combination (22,24) is co-axial with the operating rod (13), the piston (24) being provided on rod (13). A mold device for a molding machine, comprising: a fixed retainer plate (1) supporting a fixed mold (2); a movable retainer plate (5) supporting a movable mold (11) co-operable with the fixed mold (2) to define a mold cavity, a clamping cylinder (3) being arranged to move the movable retainer plate (5) towards and away from the fixed retainer plate (1) thereby to close and open the mold cavity; a revolutionary block (7) mounted on the fixed retainer plate (1) and supporting the associated fixed mold (2); and operating means (12,13; 13,27) acting on the revolutionary block (7) and coupled to the movable retainer plate (5) so as to effect rotation of the revolutionary block (7) during movable retainer plate (5) movement; characterised in that the operating means (12,13; 13,27) is arranged (14a; 22,24) not to effect rotation of the revolutionary block (7) during a first stage of movable retainer plate (5) movement when the movable mold (11) is in the vicinity of the fixed mold (2), the operating means automatically effecting rotation of the revolutionary block (7) during a second stage of the movement of the movable retainer plate (5) when the movable mold (11) has moved away from the fixed mold (2). A mold device as claimed in claim 7, wherein the operating means comprises: (a) an operating rod (13) secured at one end to the movable retainer plate (5); (b) a rack (14) formed on the operating rod (13); (c) a plane portion (14a) formed adjacent the rack (14) on the side thereof nearer said one end of the operating rod; (d) a pinion (12) furnished on a shaft (8) mounting the revolutionary block (7) on the fixed retainer plate (1), which pinion (12) meshes with said rack (14) during said second stage of movement, and overlies the plane portion (14a) during said first stage of movement. A mold device as claimed in claim 7, wherein the operating means comprises: (a) a follower piston-and-cylinder combin-ation (22,24) mounted on the movable retainer plate (5); (b) an operating rod (13) connected to the piston-and-cylinder combination (22,24) for axial movement thereby; (c) a rack (14) formed on the operating rod (13); and (d) a pinion (12) furnished on a shaft (8) mounting the revolutionary block (7) on the fixed retainer plate (1), which pinion (12) meshes with the rack (14), whereby rotation of the pinion (12) is prevented during said first stage of movement by driving the piston-and-cylinder combination (22,24) to move the operating rod (13) at the same rate as the movement of the movable retainer plate (5). A mold device as claimed in claim 9, wherein the piston-and-cylinder combination (22,24) is co-axial with the operating rod (13), the piston (24) being provided on rod (13). A mold device as claimed in any of the preceding claims, wherein there is provided a stopper (16) to limit rotary movement of the revolutionary block (7) during said second stage of the movement of the movable retainer plate, to ensure the mold (2) or (11) mounted on the revolutionary block (7) is opposed to the other mold (11 or 2) during said second stage of movement.

Inventors: HORI NOBUO, HORI, NOBUO, HORI, NOBUO, 18-21, NAKAAOKI 2-CHOME
Applicants: SANJOSEIKI SEISAKUSHO KK, KABUSHIKI KAISHA SANJOSEIKI SEISAKUSHO
Application year: 1991
Main classification: B29C45
IPC codes: B29C33, B29C45