JP2017071115A - Purge cover device of injection molding machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a purge cover device that is driven in conjunction with a drive of an injection molding machine.SOLUTION: A purge cover device (1) is constituted from a cover body (18) and a slider (19). The cover body (18) pivotably supports an arm part (29) thereof on an injection molding machine side. The slider (19) forms a long hole-like guide hole (36) and a guide pin (34) of the cover body (18) is inserted therein. The slider (19) is freely slidable in the rage where the slider does not come into contact with the stopper (21). When the injection molding machine (3) is driven backward, the cover body (18) turns and covers an injection nozzle (7) to allow purging, and when driven forward, the cover body (18) turns and exposes the injection nozzle (7) to allow a molding cycle.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a purge cover device for an injection molding machine provided in an injection device.

  The injection molding machine is generally composed of an injection device and a mold clamping device as is well known. The injection device is composed of a heating cylinder, a screw or the like provided inside the heating cylinder so as to be driven in the rotational direction and the axial direction, and a heating band heater is provided on the outer peripheral portion of the heating cylinder. Is equipped with an injection nozzle. On the other hand, the mold clamping device includes a fixed mold attached to the fixed platen, a movable mold attached to the movable platen, a mold clamping device for clamping the movable mold to the fixed die, and the like. It is configured. Therefore, an injection molded product can be obtained as follows. That is, the injection material is supplied to one end of the heating cylinder and the screw is driven to rotate. Then, the injection material is melted by heat applied from the band heater, frictional heat generated when the screw is rotationally driven, shearing heat, and the like in the process of being sent forward, and accumulated in the measuring chamber in front of the heating cylinder. When the mold clamping device is driven and the fixed mold and the movable mold are clamped, a cavity is formed between these molds. The screw is driven in the axial direction to inject and fill the cavity from the injection nozzle. After cooling and solidifying, the movable mold is opened to obtain a molded product.

  By the way, a molded product is produced by continuously performing a molding cycle, but when the molding cycle is interrupted, a molten injection material remains in the heating cylinder. Since the remaining injection material may be deteriorated by heat or the like, the molding cannot be resumed as it is. Also, when trying to obtain a molded product from an injection material with different materials, colors, properties, etc., the injection material so far remains in the heating cylinder, so molding starts as it is. I can't do it. Therefore, prior to the start of the molding cycle, the old injection material remaining in the heating cylinder, between the flights of the screw, the injection nozzle hole, etc. is purged as follows. That is, the injection device is retracted, and the injection nozzle is separated from the locating ring of the fixed mold. Then, the screw is rotationally driven in the plasticizing direction without supplying the injection material. At this time, the screw is sucked back to suppress an increase in the pressure in the measuring chamber so that the injection material does not leak from the injection nozzle. Then, the old injection material remaining between the inner peripheral wall of the heating cylinder and between the flights of the screw is sent to the measuring chamber. The screw is driven in the axial direction to discharge the old injection material from the injection nozzle. This is repeated one to several times to complete the purge. Alternatively, the purge material is plasticized and similarly discharged from the injection nozzle and purged.

  When purging as described above, it is well known that a cover is provided on the injection nozzle to prevent the purge material from splashing around. However, such a purge cover has been proposed by various documents. Yes.

Japanese Utility Model Publication No. 60-187015 JP 2013-216057 A

  Patent Document 1 discloses a cover for preventing the purge resin from scattering. This cover is provided on the injection device side, and can take two positions, a purge position that covers the injection nozzle and a retreat position that retreats from this position. The cover is driven by an air cylinder. When the purge operation is performed, the air cylinder is driven to bring the cover to the purge position, and when the purge operation is finished, the air cylinder is similarly driven to move to the retracted position. Use it like this.

  Patent Document 2 also describes a purge cover device. The purge cover device described in Patent Document 2 is provided on the stationary platen side. This purge cover device includes a shielding plate with which an injection nozzle abuts and a cover plate that prevents scattering of the injection material during purging, and these are rotated by a predetermined drive mechanism to provide two positions, a purge position and a retracted position. It can be taken. The purge position is a position where the through hole of the stationary platen into which the injection nozzle is inserted is closed by the shielding plate and the cover plate is arranged in the vicinity of the injection nozzle. The retreat position is the position where the through hole is opened and the injection nozzle is opened. The cover plate is in a separated position. Therefore, when performing injection molding, the purge cover device is driven to the retracted position to open the through hole of the stationary platen, and the injection nozzle is inserted. When purging, the injection device is retracted, the injection nozzle is pulled out from the fixed platen, and the purge cover device is driven to the purge position. Then, the shielding plate closes the through hole of the fixed platen. The injection nozzle is brought into contact with the shielding plate to measure the injection material, and when the injection nozzle is separated from the shielding plate, the cover plate covers the injection nozzle. When the injection operation is performed, the injection material is injected, but scattering is prevented by the cover plate. Purge is performed by repeating the weighing of the injection material and the injection operation.

  Both the cover described in Patent Document 1 and the purge cover device described in Patent Document 2 can take the purge position and the retracted position, and can cover the injection nozzle when driven to the purge position. It can be safely injected and discharged. If the retracted position is adopted, injection molding can be performed without hindering the cover. That is, there is no problem with injection molding and purge. However, there are problems to be solved. Specifically, the cover or purge cover device is driven by a predetermined drive mechanism, but this is problematic in that it is driven independently of the drive of the injection device. It can be seen. For example, if the injection device is accidentally moved forward while the cover or purge cover device is driven to the purge position, the cover and the fixed plate may collide, or the injection nozzle and the shielding plate of the purge cover device may collide with each other. It will be damaged. Further, when purging by moving the injection device backward, the cover or the purge cover device may be forgotten to be driven. Then, purging is performed despite the cover or purge cover device being in the retracted position, and the injection material is scattered. In other words, the cover described in Patent Document 1 and the purge cover device described in Patent Document 2 cannot completely prevent such danger because the drive thereof is not interlocked with the drive of the injection device. In order to link these drives with the drive of the injection device, it is conceivable to deal with software. Specifically, the cover or purge cover device is driven from the controller of the injection molding machine. However, in this case, it is necessary to modify the software that runs on the controller, which increases costs, and is not an effective measure.

  An object of the present invention is to provide a purge cover device that solves such a problem. Specifically, the purge cover device is provided with a purge cover that moves to a retracted position when injection molding is performed, and when purging is performed. Provided is a purge cover device in which the purge cover moves to a purge position that covers the injection nozzle, and automatically and reliably switches between a retracted position and a purge position in conjunction with driving of the injection device. The purpose is to do.

  In order to achieve the above object, the present invention comprises a purge cover device comprising a cover body and a slider. The cover body includes a cover part and an arm part having a predetermined length, and pivotally supports the tip of the arm part on a predetermined member of the injection device. The slider is slidable in parallel with the injection device, forms a long hole-shaped guide hole, and inserts a guide pin fixedly provided at a predetermined position of the arm portion of the cover body. The slider is slid back and forth in accordance with the driving of the injection device in the range behind the predetermined slide limit, and at this time, the cover portion of the cover body covers the injection nozzle. However, when the slider is at the slide limit, the forward movement is restricted, and when the injection device is driven forward in this state, the guide pin is guided by the guide hole and the cover body rotates, thereby injecting. The nozzle is exposed from the cover.

That is, in order to achieve the above object, the invention according to claim 1 is such that when the injection device is driven in the forward direction, the injection nozzle at the tip touches the mold provided on the mold plate to perform injection molding. A purge cover device for an injection molding machine that can be implemented and purges when the injection device is driven in a backward direction so that the injection nozzle is separated from the mold, and the purge cover device Is composed of a cover main body that covers the injection nozzle and a slider that is slidable in parallel with the injection device. The cover main body is integrally fixed to the cover portion and the cover portion. An arm portion having a length, and is pivotally supported by a predetermined member of the injection device at the arm portion, and the slider has an elongated guide hole formed therein, and the cover body A guide pin fixedly provided at a predetermined position of the arm portion is inserted into the guide hole, and the slider moves with the driving of the injection device in a range closer to the backward direction than a predetermined slide limit. The cover portion of the cover body covers the injection nozzle at this time, and when it is located at the slide limit, the movement in the forward direction is restricted. When driven in the forward direction, the purge is guided by the guide hole and the guide pin moves, whereby the cover body is rotated and the injection nozzle is exposed from the cover portion. Configured as a cover device.
According to a second aspect of the present invention, in the purge cover device according to the first aspect, a rod of a piston cylinder unit that drives the injection device back and forth is fixed to the mold platen, and the slider is inserted into the rod. And a predetermined stopper is fixed so as to correspond to the slide limit.
The invention according to claim 3 is the purge cover device according to claim 1 or 2, wherein the arm portion of the cover body is pivotally supported by a rotation pin with respect to a predetermined member of the injection device, An arcuate guide hole is formed concentrically with the rotating pin in a predetermined member of the injection device, and an auxiliary guide pin fixed to the arm portion is inserted into the arcuate guide hole to guide the arcuate guide hole. It is comprised as a purge cover apparatus characterized by being made.

  As described above, according to the present invention, when the injection device is driven in the forward direction, the injection nozzle at the tip can touch the mold provided on the mold plate to perform the injection molding, and the injection device is retracted. When driven in the direction, it is configured as a purge cover device of an injection molding machine in which the injection nozzle is separated from the mold and can be purged. According to the present invention, the purge cover device includes a cover main body that covers the injection nozzle and a slider that is slidable in parallel with the injection device. The cover main body is integrated with the cover portion and the cover portion. It is composed of a fixed arm portion of a predetermined length, and is pivotally supported by a predetermined member of the injection device at the arm portion, and the slider has a long hole-shaped guide hole, and the cover body A guide pin fixedly provided at a predetermined position of the arm portion is inserted into the guide hole. Since the purge cover device according to the present invention is composed of only simple members as described above, it can be manufactured at low cost. According to the present invention, the slider is slid back and forth as the injection device is driven in a range closer to the backward direction than the predetermined slide limit, and at this time, the cover portion of the cover body covers the injection nozzle become. That is, purging can be performed at this time. When the slider is located at the slide limit, the movement in the forward direction is restricted. When the injection device is driven in the forward direction in this state, the guide pin is guided by the guide hole and the cover body is thereby moved. It rotates and the injection nozzle is exposed from the cover part. That is, injection molding can be performed at this time. As described above, the cover portion of the cover body is mechanically and automatically driven according to the position of the injection device to cover the injection nozzle or to be separated from the injection nozzle and exposed. That is, the purge cover device is driven in conjunction with the driving before and after the injection device. Therefore, there is no possibility of collision between the cover main body and the injection nozzle, and the cover main body and the template, and the apparatus can be reliably protected. According to another invention, a rod of a piston cylinder unit that drives the injection device back and forth is fixed to the mold platen, and a slider is inserted into the rod and a predetermined stopper is fixed to correspond to the slide limit. Yes. Since it is comprised in this way, since a slider can be provided using the rod for driving an injection apparatus, a purge cover apparatus can be provided at low cost. According to still another invention, the arm portion of the cover body is pivotally supported by a rotation pin with respect to a predetermined member of the injection device, and the predetermined member of the injection device has an arcuate guide hole concentrically with the rotation pin. An auxiliary guide pin fixedly provided on the arm portion is inserted and guided in the arc-shaped guide hole. Therefore, the arm portion, in other words, the cover body is guaranteed to rotate smoothly because the auxiliary guide pin is guided in the guide hole on the arc.

It is a front view which shows the purge cover apparatus which concerns on this Embodiment, an injection apparatus, and a fixed platen. It is a perspective view which shows the purge cover apparatus which concerns on this Embodiment, and a part of stationary platen. It is a figure which shows the effect | action of the purge cover apparatus which concerns on this Embodiment, The (a)-(c) is a front view of the purge cover which shows the purge cover apparatus which changes according to the position of an injection apparatus, and an injection apparatus. . It is a front view which shows the purge cover apparatus which concerns on other embodiment of this invention.

  This embodiment will be described. As shown in FIG. 1, the purge cover device 1 according to the present embodiment is provided in an injection molding machine 2 according to the present embodiment. Although only a part of the injection molding machine 2 is shown in FIG. 1, the injection molding machine 2 is generally composed of an injection device 3 and a mold clamping device 4 as is well known. The injection device 3 includes a heating cylinder 6 and a screw that is driven in the rotation direction and the axial direction within the heating screw 6, and an injection nozzle 7 is provided at the tip of the heating cylinder 6. Such an injection device 3 faces the back side of the mold platen of the mold clamping device 4, that is, the fixed platen 9, and when the injection device 3 is moved forward and backward, the injection nozzle 7 is hollowed out in the fixed platen 9. Alternatively, it is inserted into the through hole 10 or retracted from the through hole 10. In the present embodiment, the injection device 3 is driven back and forth by a piston cylinder unit that is driven by hydraulic pressure, that is, a hydraulic cylinder 12, and the rod 13 of the hydraulic cylinder 12 is fixed to the stationary platen 9 and the cylinder 15 is Each is fixed to the injection device 3.

  The purge cover device 1 according to the present embodiment is provided in the injection device 3 of such an injection molding machine 2. The purge cover device 1 is shown in detail in FIG. 2, and includes a cover main body 18, a pair of sliders 19 and 19, an injection device side member 20, and a pair of stoppers 21 and 21. First, the injection device side member 20 will be described. This is a member that is integrally fixed to the injection device 3, and is fixed to the lower portion of the heating cylinder 6 in the present embodiment. However, it may be fixed to any member of the injection device 3 as long as it is fixed integrally with the injection device 3 and driven back and forth together with the injection device 3. In the present embodiment, the injection device side member 20 is formed with a pair of plate portions 23, 23 so as to be symmetrical to the left and right with respect to the axis of the injection device 3. Holes 24 and 24 having a predetermined diameter, and arc-shaped elongated holes having a predetermined width, that is, arc-shaped guide holes 26 and 26 are formed concentrically with the holes 24 and 24.

  The cover body 18 includes a cover portion 28 that covers the injection nozzle 7 from the front surface, the upper surface, and both side surfaces thereof, and a pair of pairs that are formed from the both side surfaces of the cover portion 28 and have a predetermined length in the obliquely downward rearward direction. It is comprised from the plate-shaped arm parts 29 and 29. FIG. The arm portions 29, 29 are provided with two pins 31, 32,... That is, the rotation pins 31 and 31 that are the center of rotation of the cover body 18 and the auxiliary guide pins 32 and 32 that assist the rotation. The rotation pins 31 and 31 are inserted into the holes 24 and 24 of the injection device side member 20, and the auxiliary guide pins 32 and 32 are inserted into the arcuate guide holes 26 and 26, respectively. The cover body 18 rotates about the rotation pins 31, 31, but the range in which the cover main body 18 can rotate is limited to the range in which the auxiliary guide pins 32, 32 can move within the arcuate guide holes 26, 26. Will be. The cover main body 18 is provided with a pair of guide pins 34 and 34 at predetermined portions of the pair of arm portions 29 and 29. In the present embodiment, the guide pins 34 and 34 are provided at the base portions of the arm portions 29 and 29 close to the cover body 18, but are provided at other portions such as the central portions of the arm portions 29 and 29. Also good.

  The sliders 19 are made of a plate-shaped member. The lower portions of the sliders 19 and 19 are thick, and through-holes 35 and 35 penetrating in the lateral width direction of the sliders 19 and 19 are opened in the thick portions. The pair of rods 13 and 13 fixed to the stationary platen 9 are gently inserted into the through holes 35 and 35 so that the pair of sliders 19 and 19 are smoothly slid in parallel with the injection device 3. It has become. The sliders 19 and 19 are provided with elongated guide holes 36 and 36 extending in the vertical direction. The guide pins 34, 34 of the cover body 18 are inserted into the guide holes 36, 36 so that the guide pins 34, 34 are guided. A pair of stoppers 21 and 21 are fixed to the pair of rods 13 and 13 at predetermined positions. The sliders 19 and 19 are slidable. However, when the sliders 19 and 19 come into contact with the stoppers 21 and 21, the forward movement of the sliders 19 and 19 is restricted. This contact position is the sliding limit of the stoppers 21 and 21.

  The operation of the purge cover device 1 according to the present embodiment will be described. When the hydraulic cylinder 12 is driven to bring the injection device 3 to a predetermined rear position, the injection nozzle 7 is retracted from the fixed platen 9. At this time, the sliders 19 and 19 of the purge cover device 1 are located behind the slide limit. Since the cover body 18 naturally falls downward due to gravity, the guide pins 34 and 34 are locked at the lowermost portions of the guide holes 36 and 36 of the sliders 19 and 19. Thereby, as shown in FIG. 1, the cover portion 28 of the cover body 18 is in a state of covering the injection nozzle 7. This state is a state in which purging is possible. At this time, even if the hydraulic cylinder 12 is driven and the injection device 3 is driven forward, the cover 28 is maintained in a state of covering the injection nozzle 7 until a predetermined forward position. This is because as the injection device 3 is driven, the cover main body 18 is driven forward and dragged by the guide pins 34 and 34, and the sliders 19 and 19 slide forward. Until the sliders 19 and 19 reach the slide limit, the cover portion 28 of the cover main body 18 is maintained in a state of covering the injection nozzle 7, so that the purge can be performed in the injection device 3 at an arbitrary position. When purging is performed, the injection material discharged from the injection nozzle 7 is prevented from being scattered by the cover portion 28.

  When the purge is finished and the molding cycle is started, the hydraulic cylinder 12 is driven to drive the injection device 3 forward. Then, the sliders 19 and 19 come into contact with the stoppers 21 and 21, as shown in FIG. The sliders 19 and 19 reach the slide limit, and the forward movement is restricted. When the injection device 3 is further driven forward in this state, as shown in FIG. 3A, the rotation pins 31 and 31 are driven forward, but the sliders 19 and 19 are stopped. Therefore, the guide pins 34, 34 are restricted from moving forward. Then, the guide pins 34 and 34 move upward along the guide holes 36 and 36. As a result, the cover body 18 rotates about the rotation pins 31 and 31. When the injection device 3 is further driven forward, as shown in FIG. 3C, the cover main body 18 is rotated and the cover portion 28 is completely moved to the upper portion of the injection device 3. That is, the injection nozzle 7 is exposed. The injection nozzle 7 is inserted from the cutout 10 of the fixed platen 9 and comes into contact with a sprue of a mold not shown in the drawing. Perform a molding cycle.

  When performing color change or the like in the injection device 3, purge is required. The molding cycle is stopped, the hydraulic cylinder 12 is driven, and the injection device 3 is moved backward. The injection nozzle 7 is retracted from the fixed platen 9 and operates in the reverse direction to that described above, the cover body 18 rotates in the reverse direction, and the cover portion 28 covers the injection nozzle 7. Perform a purge. The purge cover device 1 according to the present embodiment mechanically and automatically covers the injection nozzle 7 with the cover portion 28 or exposes the injection nozzle 7 in conjunction with the advance / retreat operation of the injection device 3. Therefore, not only can the purge be performed safely, but there is no risk of damaging the apparatus at the start of the molding cycle.

  The purge cover device 1 according to the present embodiment can be variously modified. FIG. 4 shows a purge cover device 1 ′ according to another embodiment. In this embodiment, the purge body 18 ′ is rotated only by the rotation pins 31, 31. Yes. That is, no auxiliary guide pin or arcuate guide hole is provided. In this embodiment, the shape of the guide hole 36 'is also changed. The guide hole 36 'is a long hole that is smoothly curved. Although not shown in the figure, other variations are possible. For example, in the present embodiment, the injection device 3 has been described as being driven by the hydraulic cylinder 12, but may be driven by another drive mechanism. In this case, in order to slide the sliders 19 and 19, it is necessary to provide another member instead of the rods 13 and 13. However, the sliders 19 and 19 are slid in parallel with the injection device 3 and at a predetermined position. Any structure may be used as long as forward movement is restricted. Furthermore, the purge cover device 1 according to the present embodiment can also be applied to a vertical injection molding machine. In the case of a vertical injection molding machine, the injection device is inserted from the back of the movable platen so that its injection nozzle touches the mold attached to the movable platen. Also in the molding machine, when the purge cover device 1 according to the present embodiment is provided, when the injection device is driven in the backward direction, the cover main body 18 can cover the injection nozzle when the injection nozzle is retracted from the movable platen. Furthermore, the purge cover device 1 according to the present embodiment can also be applied to an injection molding machine in which the mold clamping device is a saddle type and the injection device is sideways. In such an injection molding machine, the injection nozzle comes into contact with the vicinity of the parting line of the clamped mold, and the cover main body 18 is moved when the injection nozzle is separated from such a mold. The injection nozzle will be covered.

DESCRIPTION OF SYMBOLS 1 Purge cover apparatus 2 Injection molding machine 3 Injection apparatus 6 Heating cylinder 7 Injection nozzle 9 Fixed plate 10 Drilling 12 Hydraulic cylinder 13 Rod 18 Cover main body 19 Slider 20 Injection apparatus side member 21 Stopper 26 Arc-shaped guide hole 28 Cover part 29 Arm part 31 Rotating Pin 32 Auxiliary Guide Pin 34 Guide Pin 36 Guide Hole

Claims (3)

When the injection device is driven in the forward direction, the injection nozzle at the tip can touch the mold provided on the mold plate to perform injection molding, and when the injection device is driven in the backward direction, the injection nozzle A purge cover device of an injection molding machine configured to be purged away from the mold,
The purge cover device includes a cover body that covers the injection nozzle, and a slider that is slidable in parallel with the injection device.
The cover main body includes a cover portion and an arm portion having a predetermined length that is integrally fixed to the cover portion, and is pivotally supported by a predetermined member of the injection device on the arm portion. And
The slider has a long hole-shaped guide hole, and a guide pin fixedly provided at a predetermined position of the arm portion of the cover body is inserted into the guide hole.
The slider is slid back and forth with the drive of the injection device in a range closer to the backward direction than a predetermined slide limit, and at this time, the cover portion of the cover body is in a state of covering the injection nozzle, When it is located at the slide limit, movement in the forward direction is restricted, and when the injection device is driven in the forward direction in this state, the guide pin is guided by the guide hole to move the cover body. A purge cover device, wherein the purge nozzle is rotated and the injection nozzle is exposed from the cover portion.   2. The purge cover device according to claim 1, wherein a rod of a piston cylinder unit that drives the injection device back and forth is fixed to the mold plate, and the slider is inserted into the rod and corresponds to the slide limit. A purge cover device having a predetermined stopper fixed thereto.   The purge cover device according to claim 1 or 2, wherein the arm portion of the cover body is pivotally supported by a rotation pin with respect to a predetermined member of the injection device, and the predetermined member of the injection device includes An arc guide hole is formed concentrically with the rotation pin, and an auxiliary guide pin fixedly provided on the arm portion is inserted into the arc guide hole to be guided. Cover device.

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