JP4679619B2 - Blow molding equipment - Google Patents

Description

  The present invention relates to a blow molding apparatus for manufacturing a plastic container such as a plastic bottle by heating and preforming a preform which is a primary molded product. More specifically, the present invention relates to a transfer mechanism for changing the feed pitch of the preform, a reverse transfer mechanism for reversing the preform or blow molded product, and a blow molding die opening / closing mechanism that opens and closes to the left and right.

  Various types of biaxial stretch blow molding apparatuses for producing blow molded products such as PET bottles are known. Basically, a preform supply station, a heating station for heating the preform, A blow station having a blow mold for biaxially stretching and blowing the preform and a collection station for collecting the blow molded product from the blow mold are provided. A biaxial stretch blow molding apparatus having such a configuration has been proposed by, for example, the present applicant (Patent Document 1). As a blow station, a rotary type in which a plurality of blow molding dies are mounted on a turntable at a constant angular interval is known.

  Here, in the blow molding apparatus having this configuration, a large number of preforms are efficiently heated by conveying the preforms at a narrow feed pitch in the heating station, thereby reducing the size of the apparatus. For this reason, when delivering the heated preform from the heating station to the blow station, it is necessary to widen the feed pitch so that it matches the feed pitch of the blow mold. As a mechanism for widening the feed pitch and transferring the preform, as disclosed in Patent Document 2 below, a preform transported along an annular transport path with a narrow feed pitch is separated by a large feed pitch. The thing of the structure hold | gripped by the gripper apparatus conveyed along this annular | circular shaped conveyance path is known. Each gripper device is held by a swing mechanism that swings the gripper left and right, and a linear motion mechanism that linearly moves back and forth, and when receiving the preform, It is configured to receive the preform while conveying each gripper device so as to have the same feed pitch.

  In addition, the preform is conveyed via a heating station and a blow station while being held on the carrier in an inverted posture. In general, the preform in an upright posture supplied from the preform supply station is reversed, and a mandrel is inserted into the mouth from the lower side, and thereafter the preform is conveyed in this state. After the blow molding product is blow molded by the blow molding die, the mandrel is extracted downward from the mouth of the blow molded product, and then the blow molded product is inverted and collected at the collection station. I have to. A mechanism for reversing the preform and supporting it on the carrier is also disclosed in Patent Document 2 below.

On the other hand, as a blow mold, a structure in which a pair of right and left mold members are opened and closed to open and close the mold is known. As the mold opening / closing mechanism of the blow mold having this configuration, those using a link mechanism are disclosed in Patent Documents 3 and 4 below.
JP 2000-117821 A JP-A-11-115039 JP-A-6-15724 JP-A-6-39909

  In the transfer mechanism for converting the feed pitch, the gripper device is positioned by a combined motion of the swing motion by the swing mechanism and the linear motion by the linear motion mechanism. However, in order to position the gripper device at the preform receiving position or delivery position by such a combined movement, it is necessary to manufacture the components of each mechanism with high accuracy and to assemble with high accuracy. There is a problem that it is difficult and the manufacturing cost becomes high.

  Furthermore, when delivering preforms and blow-molded products between the annular conveyance paths, it is desirable that the gripper devices be opposed to each other in the radial direction of the conveyance paths. However, in the conventional mechanism, the gripper device is oriented in the radial direction only at the moment when a preform or the like is delivered. For this reason, there is a possibility that delivery of a preform or the like cannot be performed reliably.

  Next, in a conventional blow molding apparatus, generally, a turntable for performing an operation for inverting a preform, a turntable for performing an operation for inverting a blow molded product, and an operation for inserting a mandrel into the preform. Therefore, there is a need for a turntable for performing the operation for extracting the mandrel from the blow molded product. Although a mechanism for changing the preform feed pitch and reversing the preform as described above has been proposed, basically four tables are required, which increases the size of the apparatus and increases the manufacturing cost. There is a problem.

  On the other hand, in a blow molding die opening and closing mechanism that can be opened and closed in the left and right in a conventional blow molding device, the link mechanism constituting the same is a turntable that turns each blow molding die from the back of each blow molding die. It extends in the plane direction toward the center. Here, a large number of heavy blow molding dies are mounted on the turntable, and each blow molding die needs to be conveyed with high accuracy. Therefore, it is desirable that the bearing member that supports the turntable in a rotatable state is arranged as much as possible under the heavy object, that is, directly under the blow molding die in the turntable. However, since the conventional mold opening / closing mechanism is long in the planar direction from each blow mold to the rotation center of the turntable, the bearing member is located closer to the rotation center of the turntable so as not to interfere with the mold opening / closing mechanism. There is a problem that it must be installed.

  An object of the present invention is to propose a blow molding apparatus that is small and compact, and that can efficiently and reliably carry a preform or a blow molded product.

  Another object of the present invention is to provide a blow molding apparatus that can change the feed pitch of a preform or the like conveyed along an annular conveyance path by a simple mechanism, and can reliably deliver the preform or the like. To propose a transfer mechanism.

  Further, the present invention has a mechanism for reversing the preform and the blow molded container, a mechanism for inserting the carrier mandrel into the preform, and a mechanism for extracting the carrier mandrel from the blow molded container on a single turntable. Another object of the present invention is to propose a reverse transfer mechanism for a blow molding apparatus.

  Still another object of the present invention is to propose a mold opening / closing mechanism of a blow molding apparatus that can arrange a bearing supporting a turntable on which a blow molding mold is mounted at a position close to the position immediately below the blow molding mold. is there.

The present invention includes a preform supply station that supplies a preform in an upright state, a heating station that heats the preform to a temperature state suitable for blow molding while conveying the preform, and blows and blows the preform after heating. In a blow molding apparatus having a blow station for molding a molded product and a collection station for collecting the blow molded product,
A first annular conveyance path for conveying the preform supplied from the preform supply station at a first feed pitch;
A first transfer that receives a preform from the first annular conveyance path and changes the feed pitch to a second feed pitch wider than the first feed pitch while being conveyed along the second annular conveyance path. Mechanism,
The preform conveyed at the second feed pitch is received from the second annular conveyance path, and the preform is inverted to the inverted state while being conveyed along the third annular conveyance path. A reverse transfer mechanism for inserting a mandrel from the lower side into the mouth of the preform in a state,
From the third annular conveyance path, the preform conveyed with the mandrel inserted is received, and the feed pitch is changed from the second feed pitch to the second while being conveyed along the fourth annular conveyance path. A second transfer mechanism that changes to a feed pitch of 1;
An arcuate conveyance path portion that is formed in the heating station and receives a preform in a state where a mandrel is inserted from the fourth annular conveyance path;
A third preform that receives the heated preform from the arcuate conveyance path portion and changes the feed pitch from the first feed pitch to the second feed pitch while being conveyed along the fifth annular conveyance path. A transfer mechanism,
The blow station is transported at a second feed pitch along the fifth annular transport path by a blow molding die transported at a second feed pitch along the sixth annular transport path at the blow station. Receive a preform,
The reverse transfer mechanism receives a blow molded product from the blow mold and conveys the mandrel inserted into the mouth of the blow molded product in an inverted state downward while conveying along the third annular conveyance path. After pulling out, the inverted blow-molded product is inverted and brought upright,
The blow molded product is collected from the reverse transfer mechanism to the collection station ,
The reverse transfer mechanism is
A turntable,
On the surface of the turntable, a cylindrical member that extends radially about the rotation center of the turntable and is supported in a rotatable state by the turntable;
A shaft member extending through the hollow portion of the cylindrical member and rotating integrally with the cylindrical member;
A gripper attached to the outer end of the shaft member, capable of holding the mouth of the preform and blow molded product, and moving along the second annular conveyance path when the turntable rotates,
A rotating cam mechanism that rotates the cylindrical member 180 degrees as the turntable rotates;
An insertion / removal mechanism for inserting / removing the mandrel with respect to the mouth of the inverted preform or blow molded product,
During one turn of the turntable, the preform is inverted to the inverted state, the mandrel is inserted into the mouth of the inverted preform, the mandrel is pulled out from the mouth of the inverted blow molded product, and It is characterized in that the blow molded product in an inverted state is inverted to an upright state .

Here, the first, second, and third transfer mechanisms are respectively
A turntable,
An annular guide rail fixed on the surface of the turntable so that the center of rotation of the turntable is the center,
A plurality of sliders slidable along the annular guide rail;
A holding part for holding a preform, a blow molded product or a mandrel formed on each slider;
On the inner position of the arcuate guide rail in the turntable, swing pins arranged in a freely rotatable state at a predetermined angular interval on a concentric circle centered on the rotation center of the turntable;
A plurality of swing arms that swing along the surface of the turntable around each swing pin as the turntable rotates,
The oscillating end of each oscillating arm is characterized by having a slidable connecting portion that is slidably connected to each slider in the axial direction of the oscillating arm.

  The swing cam mechanism for swinging each swing arm as the turntable rotates includes an arm extending in a direction orthogonal to each swing pin, a cam follower attached to the tip of the arm, and the cam follower It can be set as the structure provided with the stationary platen in which the cam groove to slide is formed.

  In the transfer mechanism of the blow molding apparatus according to the present invention, the holding portion is attached to the slider that slides along the annular guide rail, and the slider is swung left and right by the swing arm according to the rotation of the turntable. The pitch is changed. The feed pitch can be changed with high accuracy by a simple mechanism. In addition, since the holding portion for holding the preform attached to the slider is always directed in the radial direction, the operation of receiving the preform etc. conveyed along the annular conveyance path, and the preform etc. The operation of handing over the annular conveyance path can be performed reliably.

Next, an upright or inverted preform or blow-molded product conveyed along the first annular conveyance path was received, and the posture was reversed while being conveyed along the second annular conveyance path. Later, the reverse transfer mechanism of the blow molding device handed over to the third annular conveyance path is:
A turntable,
On the surface of the turntable, a cylindrical member that extends radially around the rotation center of the turntable and is supported in a rotatable state by the turntable;
A shaft member extending through the hollow portion of the cylindrical member and rotating integrally with the cylindrical member;
A gripper attached to the outer end of the shaft member, capable of holding a mouth of a preform or blow molded product, and moving along the second annular conveyance path when the turntable rotates;
And a rotating cam mechanism that rotates the cylindrical member 180 degrees as the turntable rotates.

Here, the rotating cam mechanism of the reverse transfer mechanism of the present invention is:
First and second cam followers formed on a slider capable of reciprocating in the axial direction of the cylindrical member;
A first cam groove formed on the outer peripheral surface of the cylindrical member in a spiral manner over an angular range of 180 degrees, in which the first cam follower slides;
A second cam groove formed on the surface of the stationary plate and through which the second cam follower slides;
The shape of the second cam groove may be defined such that the slider reciprocates in the radial direction according to the rotation of the turntable.

The gripper includes a pair of opening and closing claws that can be opened and closed,
And a claw opening / closing mechanism for opening / closing the opening / closing claw,
The claw opening / closing mechanism includes a sliding cam mechanism that slides the shaft member in the axial direction of the cylindrical member, and a link mechanism that converts the sliding of the shaft member into an opening / closing operation of the opening / closing claw. Can do.

Furthermore, it has an insertion / removal mechanism for inserting / removing the mandrel to / from the mouth of the inverted preform or blow molded product,
The insertion / removal mechanism may include a mandrel support member that can move up and down at a position directly below each gripper, and a lift cam mechanism that lifts and lowers the mandrel support member in accordance with the rotation of the turntable.

  As described above, in the transfer mechanism of the blow molding apparatus according to the present invention, the slider having the holding portion for holding the preform or the like is slidably disposed along the annular guide rail, and each slider is rotated by the turntable. The feed pitch of the preform or the like held by the holding unit is changed by sliding left and right according to the change.

  Therefore, the configuration can be simplified compared to the conventional mechanism for changing the feed pitch of the preform or the like held by the holding portion by the combined motion combining the swinging motion and the telescopic motion. Can change. Further, since the holding portion attached to the slider that slides along the annular guide rail is always in the state of facing the radial direction of the turntable, the preform or the like conveyed along the annular conveyance path is received. It is possible to reliably perform the operation and the operation of delivering the preform or the like to the annular conveyance path.

  In the reverse transfer mechanism of the blow molding apparatus of the present invention, the operation of receiving and reversing the preform in accordance with the rotation of the turntable, the operation of inserting the mandrel into the mouth of the reversed preform, and receiving the blow molded product An operation of pulling out the mandrel from the mouth portion and an operation of inverting the blow molded product after pulling out the mandrel are configured. Therefore, compared with the conventional blow molding apparatus which performed each of these operation | movement using the separate turntable, the conveyance mechanism of a preform and a blow molded product can be comprised compactly and compactly. Further, since the conveyance path can be shortened, the production efficiency is also improved.

  Hereinafter, an embodiment of a blow molding apparatus to which the present invention is applied will be described with reference to the drawings.

(overall structure)
FIG. 1 is a schematic plan view showing the overall configuration of the biaxial stretch blow molding apparatus according to the present embodiment. Referring to this figure, the biaxial stretch blow molding apparatus 1 is, for example, a beverage bottle manufacturing apparatus, and transports the preform 2 and a preform supply station 3 that supplies the preform 2. However, a heating station 4 for heating to a temperature state suitable for blow molding, a rotary blow station 6 for blowing the heated preform 2 to form a PET bottle 5 (blow molded product), and a PET bottle 5 And a recovery station 7 for recovery.

  The preform supply station 3 includes a guide rail 8 that is inclined downward toward the supply destination. A flange 2b of the mouth portion 2a of the preform 2 is suspended on the preform supply station 3, and the preform supply station 3 is in the upright state. The reform 2 falls along the guide rail 8 by its own weight (for example, refer to FIG. 3 described later for the preform 2).

  A first annular transport path 9 for transporting the preform 2 supplied from the preform supply station 3 at the first feed pitch p1 is formed horizontally at the lower end of the guide rail 8 in the preform supply station 3. ing. The first annular transport path 9 is opposed to the turntable 10 having ratchet-shaped feed grooves formed at the same interval as the first feed pitch on the outer peripheral end surface, and the outer peripheral end surface 10a of the turntable 10. And an arcuate guide surface 11 formed over an angle of approximately 180 degrees. The preform 2 is fed out along the first annular transport path 9 at the first feed pitch p1 with the mouth portion 2a sandwiched between them.

  At a position adjacent to the first annular conveyance path 9, the second annular ring that receives the preform 2 from the first annular conveyance path 9 and circumscribes the first annular conveyance path 9 is provided. A first transfer mechanism 13 is disposed that changes the feed pitch to a second feed pitch p2 wider than the first feed pitch p1 while conveying the preform 2 along the transport path 12.

  Further, a third annular conveyance path that receives the preform 2 conveyed at the second feed pitch p2 from the second annular conveyance path 12 and circumscribes the second annular conveyance path 12 is provided. 14, the preform 2 is inverted in an inverted state while being conveyed, and then an inversion transfer mechanism 16 for inserting the mandrel 15 from the lower side into the mouth portion 2 a of the inverted preform 2 is disposed.

  Further, the preform 2 being conveyed with the mandrel 15 inserted into the mouth portion 2a from the third annular conveying path 14, in other words, the mandrel 15 being conveyed with the preform 2 being inserted. And the feed pitch is returned from the second feed pitch p2 to the first feed pitch p1 while being conveyed along the fourth annular conveyance path 17 circumscribing the third annular conveyance path 14. A second transfer mechanism 18 is arranged.

  Here, the heating station 4 includes a drive-side sprocket 19 and a driven-side sprocket 20, a chain 21 spanned between them, and a mandrel carrier 22 attached to the chain 21 at regular intervals. 22 is transported along an oblong transport path 23. The conveyance path 23 includes a semicircular conveyance path portion 25 (arc-shaped conveyance path portion) that receives the preform 2 from the fourth annular conveyance path 17 of the second transfer mechanism 18 and carries the preform 2 on the mandrel carrier 22. It is. A plurality of heating units 24 (1) to 24 (5) are arranged along the conveyance path 23, and each mandrel carrier 22 that has received the preform 2 from the second transfer mechanism 18 moves along the conveyance path 23. While being conveyed, the preform 2 is heated to a temperature state suitable for blow molding through these heating portions.

  At the adjacent position on the opposite side of the second transfer mechanism 18 in the semicircular conveyance path portion 25, the heated preform 2 is received by the mandrel carrier 22 from the conveyance path portion 25, and the fifth annular conveyance is performed. A third transfer mechanism 27 is arranged to increase the feed pitch from the first feed pitch p1 to the second feed pitch p2 while transporting along the path.

  The blow station 6 is disposed adjacent to the third transfer mechanism 27. The blow station 6 is equipped with a turntable 28 and a plurality of blow molding dies 29 arranged concentrically on the surface at intervals corresponding to the second feed pitch p2. The blow mold 29 is composed of a pair of mold members 30, 31 that open and close to the left and right, and a mold opening / closing mechanism 33 for opening and closing the mold members 30, 31 is disposed on the back side of each blow mold 29. Has been.

  In the blow station 6, the blow mold 29 circulates along the sixth annular conveyance path 34 at the second feed pitch p <b> 2 by the rotation of the turntable 28. Each blow molding die 29 receives the preform 2 conveyed at the second feed pitch p2 along the fifth annular conveyance path 26 in the mold open state, and enters the sixth annular conveyance path 34. The mold 2 is clamped while being conveyed, and the preform 2 is subjected to biaxial stretch blow molding. The plastic bottle 5 thus obtained is delivered to the star wheel 35 from the blow mold 29 in the mold open state. Arc grooves 35a are formed on the outer peripheral surface of the star wheel 35 at intervals corresponding to the second feed pitch p2, and the PET bottle 5 is conveyed toward the reverse transfer mechanism 16 by the arc grooves 35a.

  The reverse transfer mechanism 16 receives the plastic bottle 5 from the star wheel 35 and moves the mandrel 15 inserted into the mouth portion 2a of the inverted plastic bottle 5 downward while transporting along the third annular transport path 14. After that, the inverted plastic bottle 5 is inverted and brought into an upright state. Then, the plastic bottle 5 is delivered to the collection station 7 via the star wheel 36.

  In the biaxial stretch blow molding apparatus 1 having this configuration, the reverse transfer mechanism 16 reverses the preform 2 and the plastic bottle 5 as a blow molded product, inserts the mandrel 15 into the mouth 2a of the preform 2, and the pet. An operation of pulling out the mandrel 15 from the mouth 2a of the bottle 5 is performed. Therefore, compared with the conventional biaxial stretch blow molding apparatus which performed these operation in the separate place, an apparatus can be comprised small and compact, and manufacturing cost can also be held down low.

(Transfer mechanism)
2 and 3 are a plan view and a cross-sectional view showing the first transfer mechanism 13 described above. Referring to these drawings, the first transfer mechanism 13 receives the preform 2 conveyed at the first feed pitch p1 along the first annular conveyance path 9 as described above. The feed pitch is expanded from the first feed pitch p1 to the second feed pitch p2 while transporting the preform 2 along the second annular transport path 12, and the third circle of the reverse transfer mechanism 16 is moved. This is for delivery to the annular conveyance path 14.

  The first transfer mechanism 13 includes a cylindrical housing 41 fixed vertically to the apparatus base 40, and a rotating shaft 42 that is coaxially supported inside the cylindrical housing 41 in a rotatable state. The rotary shaft 42 is rotationally driven by a drive motor (not shown). A disc-shaped turntable 43 is fixed horizontally on the upper end of the rotating shaft 42 in a coaxial state. An annular guide rail 44 is fixed to the surface of the turntable 43 so as to be centered on the rotation center 43a of the turntable 43, that is, in a concentric state.

  A plurality of flat, rectangular parallelepiped sliders 45 are attached to the annular guide rail 44 so as to be slidable in a posture oriented in the radial direction. In the illustrated example, six sliders 45 are attached. A holding plate 46 in which a semicircular holding groove 46 a in which the mouth flange 2 a of the preform 2 can be placed is horizontally attached to the outer end of each slider 45.

  A plurality of oscillating pins 47 are vertically attached to a portion of the turntable 43 that is closer to the center than the annular guide rail 44 in a concentric manner at a fixed angular interval. That is, each swing pin 47 is rotatably held by a cylindrical bearing holder 48 extending through the turntable 43. The inner end of the swing arm 49 is fixed to the upper end of the swing pin 47 protruding upward from the upper end of the bearing holder 48. Each swing arm 49 extends toward the outer peripheral side along the surface of the turntable 43, and can swing left and right along the surface of the turntable 43 around the swing pin 47.

  The tip of each swing arm 49 is connected to the inner end side of each slider 45 through a slide type connecting portion 50. The slidable connecting portion 50 includes a long hole 51 formed in the tip of the swing arm 49 and extending in the axial direction of the swing arm 49, and a cam follower pin 52 slidable along the long hole 51. The cam follower pin 52 is fixed to a portion on the inner end side in the center of the upper surface of the slider 45.

  Here, each swing arm 49 is configured to swing left and right with the rotation of the turntable 43 by the cam mechanism 53. The cam mechanism 53 includes a fixed disk 54 that is horizontally fixed to the housing 41 at a position away from the back surface of the turntable 43, and a deformed heart-shaped cam groove 55 formed on the surface of the fixed disk 54. And a roller-shaped cam follower 56 that slides along the cam groove 55. The lower end of the swing pin 47 protrudes downward from the back surface of the turntable 43, and an original end portion of an arm 57 extending in a direction orthogonal to the swing arm 49 is fixed to the front end of the arm 57. A cam follower 56 is attached.

  The operation of the first transfer mechanism 13 having this configuration will be described. When the turntable 43 is rotated in the direction of the arrow, the annular guide rail 44, the sliders 45, and the swing arm 49 mounted thereon are also rotated in the same direction. Here, the cam follower 56 of the cam mechanism 53 connected to each swing arm 49 slides along a deformed heart-shaped cam groove 55 formed in the fixed disk 54. Since the cam groove 55 draws a deformed heart-shaped locus, when the cam follower 56 slides along the cam groove 55, the cam follower 56 moves in the radial direction with respect to the swing pin 47 at the fixed position. As a result, the swing pin 47 is rotated left and right, and the swing arm 49 whose inner end is fixed to the swing pin 47 also swings left and right. Since each slider 45 is connected to the tip of the swing arm 49 so as to be slidable in the axial direction thereof, when the swing arm 49 swings left and right, the slider 45 moves left and right along the annular guide rail 44. Slide to. That is, each slider 45 rotates in the same direction together with the turntable 43 while relatively moving in the approaching and leaving directions according to the shape of the deformed heart-shaped cam groove 55.

  Accordingly, by appropriately setting the shape of the deformed heart-shaped cam groove 55, the second annular conveyance path 12 and the second annular path 12 drawn by the center of the holding groove 46a of the holding plate 46 attached to the outer end of the slider 45 are provided. At the circumscribing position with respect to the one annular conveyance path 9, the distance between the sliders 45 can be narrowed and conveyed at the first feed pitch p1. Further, at the circumscribed position between the second annular conveyance path 12 and the third annular conveyance path 14 to which the preform is delivered, the distance between the sliders 45 can be widened and conveyed at the second feed pitch p2. it can. As a result, the preform 2 conveyed at the first feeding pitch p1 along the first annular conveying path 9 is received by the holding groove 46a of the holding plate 46 attached to the tip of the slider 45, and the second feeding pitch. Thus, the preform 2 can be delivered to the third annular conveyance path 14.

  In the first transfer mechanism 13 having this configuration, the mechanism only needs to swing the swing arm as compared to a mechanism that performs pitch conversion by expanding and contracting the swing arm, such as a conventional pitch conversion transfer mechanism. Becomes easier. Further, the assembly of the component parts is simplified, and the assembly error can be suppressed. Further, since the slider 45 oscillated by the oscillating arm 49 slides along the annular guide rail 44, the semicircular holding groove 46a of the holding plate 46 attached to the tip of the slider 45 always faces the radial direction. . Therefore, it is possible to reliably perform the delivery operation of the preform conveyed along the annular conveyance path.

  In addition, since the 2nd transfer mechanism 18 and the 3rd transfer mechanism 27 are also comprised similarly to said 1st transfer mechanism 13, those description shall be abbreviate | omitted.

(Reverse transfer mechanism)
Next, FIGS. 4 and 5 are a sectional view and an enlarged partial sectional view showing the reverse transfer mechanism 16. As described above, the reverse transfer mechanism 16 receives the preform 2 in the upright posture being conveyed along the second annular conveyance path 12 of the first transfer mechanism 13, and receives the third annular conveyance path. 14, the mandrel 15 is inserted into the mouth portion 2 a from the lower side after the posture is inverted while the posture is reversed while being transported along the belt 14, and then the fourth annular transport path 17 of the second transfer mechanism 18. It is for handing over. In addition, after receiving the inverted plastic bottle 5 from each blow molding die 29 of the blow station 6 and transporting it along the third annular transport path 14, the mandrel 15 is pulled out downward from the mouth 2a. The posture is reversed to make it upright, and then handed over to the star wheel 36 of the collection station 7.

  Referring to FIGS. 1, 4, and 5, the reverse transfer mechanism 16 includes a cylindrical housing 61 that is vertically fixed to the apparatus base 40, and a rotation that is rotatably supported coaxially within the housing 61. The turntable 63 is horizontally fixed to the upper end portion of the rotating shaft 62 in a coaxial state. The turntable 63 is rotationally driven by a drive motor (not shown) via a rotary shaft 62.

  On the surface of the turntable 63, a plurality of cylindrical members 65 are arranged radially in a horizontal state at regular angular intervals around the rotation center 63a, and each cylindrical member 65 is rotatable around its axis 65a. It is supported on the surface of the turntable 63. In the illustrated example, eight cylindrical members 65 are arranged. A slide shaft 66 is coaxially disposed in each cylindrical member 65 so as to penetrate the hollow portion. The slide shaft 66 rotates integrally with the cylindrical member 65 and has an axis 65a with respect to the cylindrical member 65. It is possible to slide in the direction.

  Further, a gripper 68 having a pair of opening and closing claws 68 a and 68 b capable of gripping the mouth portion 2 a of the preform 2 and the PET bottle 5 from both sides is connected to the outer end of each cylindrical member 65 via a link mechanism 67. Has been. The preform 2 and the plastic bottle 5 held by each gripper 68 are transported along the third annular transport path 14 when the turntable 63 rotates.

  The upper end of the vertical rotating shaft 62 is supported in a freely rotatable state by a bearing supported by a cylindrical bearing holder 69. The bearing holder 69 is a horizontal fixed disk fixed to the upper end surface thereof in a coaxial state. It is fixed to the side of the device mount via 70.

  Here, with the rotation of the turntable 63, the gripper 68 connected to the tip of the cylindrical member 65 is rotated 180 degrees to reverse the preform 2 or the PET bottle 5 gripped here. It has a mechanism. The reversing cam mechanism includes a slider 71 capable of reciprocating in the direction of the axis 65a of the cylindrical member 65 at the upper position of the cylindrical member 65, a first cam follower 72 attached to the lower surface of the slider 71, and the slider And a second cam follower 73 attached to the upper surface of 71. In addition, a first cam groove 74 formed spirally over an angular range of 180 degrees along the outer peripheral surface of the cylindrical member 65 is provided, and the first cam follower 72 slides along the cam groove 74. It is supposed to be. Further, a second cam groove 75 formed on the back surface of the horizontal fixed disk 70 is provided, and the second cam follower 73 slides along the cam groove 75.

  By appropriately setting the shape of the second cam groove 75, when the turntable 63 rotates, the second cam follower 73 that slides along the cam groove 75 reciprocates in the direction of the axis 65a of the cylindrical member 65. Can be moved. A first cam follower 72 is attached to the slider 71 to which the second cam follower 73 is attached. When the first cam follower 72 reciprocates in the direction of the axis 65a, the slider 71 is supported in a rotatable state. Since the cylindrical member 65 rotates 180 degrees, the slide shaft 66 and the link mechanism 67 that rotate together with the cylindrical member 65 also rotate 180 degrees. Further, the gripper 68 connected to the tip of the cylindrical member 65 can be reversed 180 degrees.

  Next, an opening / closing cam mechanism that opens and closes the gripper 68 by sliding the slide shaft 66 in the direction of the axis 65a will be described. This open / close cam mechanism includes a cylindrical cam surface 81 formed on the outer peripheral surface of the bearing holder 69, a roller 82 attached to the inner end of the slide shaft 66, and a coil spring 83 that presses the roller 82 against the cylindrical cam surface 81. And. As the turntable 63 rotates, the roller 82 of the slide shaft 66 moves along the cylindrical cam surface 81. Therefore, by appropriately setting the contour shape of the cylindrical cam surface 81, the slide shaft 66 can be reciprocated along the axis 65a. For example, when the slide shaft 66 is pushed outward, the link mechanism 67 that connects the tip of the slide shaft 66 and the gripper 68 pushes and opens the opening and closing claws 68a and 68b of the gripper 68 to the left and right. When the is pulled inward, the open / close claws 68a and 68b are operated to close.

  Next, immediately below each gripper 68 protruding outward from the outer peripheral end of the turntable 63, the mandrel 15 is inserted into the preform 2 or the mouth portion 2a of the plastic bottle 5 from the lower side, and from the mouth portion 2a. A mandrel holder 85 for pulling down the mandrel 15 is disposed. The mandrel holder 85 is attached to a lift slider 87 that moves up and down along a guide shaft 86 extending vertically downward from a position corresponding to each gripper 68 on the back surface of the turntable 63. A cam follower 88 is fixed to the elevating slider 87, and the cam follower 88 slides along a cylindrical cam groove 89 a formed on the outer peripheral surface of a cylindrical member 89 fixed to the device mount 40. By appropriately setting the cylindrical cam groove 89a, the mandrel holder 85 is moved up and down as the turntable 63 rotates, and the mandrel 15 is inserted into the mouth 2a of the inverted preform 2 from below. Can do. Moreover, the mandrel 15 can be pulled out from the mouth 2a of the inverted plastic bottle 5.

  In the present embodiment, as shown in FIG. 1, the preform 2 is inverted in the inverted state in the section 14a in the third annular conveyance path 14, and the preform 2 in the inverted state in the first half of the next section 14b. A mandrel 15 is inserted into the mouth 2a from below. Further, the mandrel 15 is pulled downward from the mouth portion 2a of the inverted plastic bottle 5 in the section 14c, and the plastic bottle 5 is inverted in the next section 14d to be in an upright posture.

  In the reversing transfer mechanism 16 having this configuration, as the turntable 63 rotates, the preform 2 is reversed, the mandrel 15 is inserted, the mandrel 15 is pulled out from the PET bottle 5, and the PET bottle 5 is reversed. be able to. Therefore, compared to the conventional blow molding apparatus configured to perform each operation on the turntables arranged at four locations, the conveyance path can be configured more compactly, so that the apparatus size can be reduced accordingly. Manufacturing costs can also be reduced.

(Mold opening / closing mechanism)
Next, FIG. 6 is a partial sectional view showing the rotary blow station 6, FIG. 7 is a partial sectional view showing a mold opening / closing mechanism 33 of the blow molding die 29, and FIG. 8 is a plan view of the mold opening / closing mechanism 33. It is a block diagram. FIG. 9 is a side view showing a side surface on the opening / closing end side of the mold opening / closing mechanism, and FIG. 10 is a side view showing a side surface on the opening / closing center side of the mold opening / closing mechanism. With reference to these drawings, the overall configuration of the blow station 6 and the mold opening / closing mechanism 33 of the blow mold 29 will be described.

  As described above, the blow station 6 is a rotary type in which a plurality of blow molds 29 circulate on the turntable 28 along the sixth annular conveyance path 34 at the second feed pitch p2. The turntable 28 is horizontally supported by a thrust bearing 91 supported by the device mount 40 so as to be rotatable about the rotation center line 28a. That is, the turntable 28 is fixed to the inner ring 91a of the thrust bearing 91, and the inner teeth 91b are formed on the inner peripheral surface of the inner ring 91a. The internal teeth 91b mesh with a drive-side external gear 93 that is coaxially fixed to the upper end of a vertical rotation shaft 92 that is rotationally driven by a drive motor (not shown). The turntable 28 is rotated about the rotation center line 28a by the drive motor.

  Each blow mold 29 includes mold members 30 and 31 that can be opened and closed to the left and right, and the mold members 30 and 31 are supported by left and right mold support members 94 and 95 that are fixed to the outer surface, respectively. These mold support members 94 and 95 can be opened and closed left and right about a vertical shaft 96, and the vertical shaft 96 is supported by a mold support plate 97 fixed to the upper surface of the turntable 28.

  The mold support members 94 and 95 that support the left and right mold members 30 and 31 are opened and closed left and right by a mold opening and closing mechanism 33 including a link mechanism. The mold opening / closing mechanism 33 includes an elevating shaft 98 disposed at a position on the back side of the vertical shaft 96 (center side of the turntable 28). The elevating shaft 98 penetrates the mold support plate 97 and the turntable 28. It extends. A slide guide 99 attached to the mold support plate 97 is disposed at a position on the back side of the lift shaft 98 (center side of the turntable 28). The slide guide 99 extends from the blow mold 29 toward the rotation center line 28 a of the turntable 28, and the slider 100 can slide along the slide guide 99. The slider 100 and a portion of the lifting shaft 98 that protrudes above the die support plate 97 are connected by a connecting arm 101 that is pin-coupled to each other.

  The slider 100 and the left and right mold support members 94, 95 are connected by an opening / closing link mechanism 102 that converts the sliding motion of the slider 100 into the opening / closing motion of the mold support members 94, 95. The opening / closing link mechanism 102 includes a pair of left and right operation arms 103 and 104, as can be seen from FIG. These operation arms 103 and 104 have a symmetrical shape, and one end thereof is connected to the slider 100 so as to be rotatable left and right around the connection pins 105a and 105b. Bending arm portions 103a and 104a extending in parallel to each other, and parallel arm portions 103b and 104b extending in parallel with each other from their tips. The distal ends of the parallel arm portions 103b and 104b are connected to both ends on the back side of the mold support members 94 and 95 so as to be rotatable left and right around the connection pins 106a and 106b.

  The mold opening / closing mechanism 33 is in a state indicated by a solid line in FIGS. When the elevating shaft 98 is lowered from this state, the slider 100 slides horizontally toward the center side of the turntable 28 and reaches a position 100A indicated by an imaginary line. When the slider 100 slides, the left and right operation arms 103 and 104 connected thereto also move to the center side of the turntable 28 as a whole. As a result, the left and right mold support members 94 and 95 connected to the ends of the operation arms 103 and 104 open to the left and right around the vertical axis 96, and are in positions indicated by imaginary lines in FIG. The left and right mold members 30, 31 are opened. Thereby, a mold open state is formed. In this state, when the elevating shaft 98 is raised and returned to the position indicated by the solid line in FIG. 6, the slider 100 slides in a direction approaching the blow molding die 29, so that it is connected to the ends of the operation arms 103 and 104. The left and right mold support members 94 and 95 are closed with respect to each other about the vertical axis 96, and a mold clamping state is formed.

  Here, the lifting shaft 98 is lifted and lowered by the lifting cam mechanism 110. The lifting cam mechanism 110 includes a cam follower 111 attached to the lower end portion of the lifting shaft 98 and a cylindrical cam groove 113 formed on the outer peripheral surface of the cylindrical member 112 supported by the device mount 40. When the turntable 28 rotates, the cam follower 111 slides along the cylindrical cam groove 113. If the cylindrical cam groove 113 is moved up and down according to the rotational position of the turntable 28, the lifting shaft 98 can be lifted and lowered according to the rotation of the turntable 28. That is, the blow mold 29 can be opened and closed according to the rotational angle position of the turntable 28.

  An elevating slider 114 is fixed to the lower end portion of the elevating shaft 98, and the elevating slider 114 is attached to a vertical slide guide 115 attached to a vertical plate portion formed vertically on the die support plate 97. It goes up and down along.

  Next, the open / close ends of the left and right mold support members 94 and 95 are provided with a closing mechanism 120 for holding the mold support members in a closed state. The closing mechanism 120 includes an elevating type stop pin 121, pin holes 94a and 95a formed at the opening and closing ends of mold support members 94 and 95 into which the stop pin 121 can be inserted from above, and the stop pin 121 as a pin hole. And a locking mechanism 122 for locking in a state of being removed from 94a and 95a. Further, a cam mechanism 123 for raising and lowering the stop pin 121 is provided.

  The locking mechanism 122 includes a groove 121 a formed on the outer peripheral surface of the stop pin 121, a ball 124 disposed on the mold support member that can be fitted into the groove 121 a, and the ball 124 toward the outer peripheral surface of the stop pin 121. It comprises a plunger provided with a biased coil spring 125. The cam mechanism 123 includes a cam follower 126 attached to the lower end of the stop pin 121 and a cam groove 127 through which the cam follower 126 slides. The cam groove 127 is a cam groove formed on the circular inner peripheral surface of the member supported by the device mount 40.

  In accordance with the rotational position of the turntable 28, the set pin 121 is lowered to the locked position shown in FIGS. 6, 7, and 9 and raised to a position that is out of the pin holes 94a and 95a. The locking pin 121 is moved up and down in conjunction with the opening and closing of the mold opening / closing mechanism 33, and is held closed by the locking pin 121 in the mold clamping state. In the open state, the locking pin 121 prevents the set pin 121 from falling from the pin holes 94a and 95a.

  In the mold opening / closing mechanism 33 of the blow mold 29 configured as described above, the lifting / lowering movement of the lifting / lowering shaft 98 is converted into the sliding movement of the slider 100, and the sliding movement of the slider 100 is performed to the left and right via the pair of operation arms 103 and 104. The mold support members 94 and 95 supporting the mold members 30 and 31 are converted into opening and closing motions. Therefore, the mold opening / closing mechanism can be made smaller and more compact than a conventional mold opening / closing mechanism in which mold opening and clamping are performed by a link mechanism configured using a large number of three or more arms. In particular, the length dimension from the back surface of the blow mold 29 toward the center of the turntable can be shortened. As a result, the thrust bearing 91 that rotatably supports the turntable 28 can be installed at a position close to the position immediately below the blow molding die 29. Therefore, the rotational movement of the turntable 28 on which the heavy blow mold is mounted can be smoothly performed.

  In addition, the locking mechanism 122 for locking the left and right mold support members 94 and 95 in the closed state is configured to fit the ball 124 in the groove 121a formed on the outer peripheral surface of the locking pin 121. Can be fixed.

It is a schematic plan view which shows the whole structure of the biaxial stretch blow molding apparatus to which this invention is applied. It is a top view which shows the 1st transfer mechanism in the biaxial stretch blow molding apparatus of FIG. It is sectional drawing which shows the 1st transfer mechanism of FIG. It is sectional drawing which shows the inversion transfer mechanism in the biaxial stretch blow molding apparatus of FIG. FIG. 5 is an enlarged partial cross-sectional view of the reverse transfer mechanism of FIG. 4. It is a fragmentary sectional view which shows the rotary type blow station in the biaxial stretch blow molding apparatus of FIG. It is a fragmentary sectional view which shows the type | mold opening / closing mechanism of the blow molding die of FIG. It is a plane block diagram of the type | mold opening / closing mechanism of the blow molding die of FIG. It is a side view which shows the side surface by the side of the opening / closing end of the type | mold opening / closing mechanism of FIG. It is a side view which shows the side surface of the opening-closing center side of the type | mold opening / closing mechanism of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Biaxial stretch blow molding apparatus 2 Preform 2a Mouth part 2b Mouth flange 3 Preform supply station 4 Heating station 5 PET bottle 6 Blow station 7 Collection | recovery station 9 1st annular conveyance path 12 2nd annular conveyance path 13 First transfer mechanism 14 Third annular transfer path 15 Mandrel 16 Reverse transfer mechanism 17 Fourth annular transfer path 18 Second transfer mechanism 25 Transfer path portion 26 Fifth annular transfer path 27 Third Transfer mechanism 28 Turntable 28a Rotation center line 29 Blow molds 30, 31 Left and right mold members 33 Mold opening / closing mechanism 34 Sixth annular transport path 40 Device mount 43 Turntable 44 Annular guide rail 45 Slider 46 Holding plate 46a Holding groove 47 Oscillating pin 49 Oscillating arm 50 Sliding connection part 51 Long hole 52 Cam follower pin 5 3 Cam mechanism 55 Deformed heart-shaped cam groove 56 Cam follower 63 Turntable 65 Cylindrical member 65a Axis 66 Slide shaft 67 Link mechanism 68 Gripper 68a, 68b Opening / closing claw 71 Slider 72 First cam follower 73 Second cam follower 74 First cam Groove 75 Second cam groove 81 Cylindrical cam surface 82 Roller 83 Coil spring 85 Mandrel holder 86 Guide shaft 87 Lifting slider 88 Cam follower 89a Cylindrical cam groove 91 Thrust bearing 94, 95 Type support member 94a, 95a Pin hole 96 Vertical shaft 97 Type Support plate 98 Elevating shaft 99 Slide guide 100 Slider 101 Connecting arm 102 Opening / closing link mechanism 103, 104 Operating arm 110 Elevating cam mechanism 111 Cam follower 113 Cylindrical cam groove 114 Elevating slider 120 Closing mechanism 121 Stop pin 1 21a Groove 122 Lock mechanism 123 Cam mechanism 124 Ball 125 Coil spring 126 Cam follower 127 Cam groove

Claims (6)

A preform supply station for supplying the preform in an upright state, a heating station for heating the preform to a temperature suitable for blow molding while conveying the preform, and blowing the preform after heating to form a blow molded product In a blow molding apparatus having a blow station for collecting and a collection station for collecting a blow molded product,
A first annular conveyance path for conveying the preform supplied from the preform supply station at a first feed pitch;
A first transfer that receives a preform from the first annular conveyance path and changes the feed pitch to a second feed pitch wider than the first feed pitch while being conveyed along the second annular conveyance path. Mechanism,
The preform conveyed at the second feed pitch is received from the second annular conveyance path, and the preform is inverted to the inverted state while being conveyed along the third annular conveyance path. A reverse transfer mechanism for inserting a mandrel from the lower side into the mouth of the preform in a state,
From the third annular conveyance path, the preform conveyed with the mandrel inserted is received, and the feed pitch is changed from the second feed pitch to the second while being conveyed along the fourth annular conveyance path. A second transfer mechanism that changes to a feed pitch of 1;
An arcuate conveyance path portion that is formed in the heating station and receives a preform in a state where a mandrel is inserted from the fourth annular conveyance path;
A third preform that receives the preform after heating from the arcuate conveyance path portion and changes the feed pitch from the first feed pitch to the second feed pitch while being conveyed along the fifth annular conveyance path. A transfer mechanism,
The blow station is transported at a second feed pitch along the fifth annular transport path by a blow molding die transported at a second feed pitch along the sixth annular transport path at the blow station. Receive a preform,
The reverse transfer mechanism receives a blow molded product from the blow mold and conveys the mandrel inserted into the mouth of the blow molded product in an inverted state downward while conveying along the third annular conveyance path. After pulling out, the inverted blow-molded product is inverted and brought upright,
The blow molded product is collected from the reverse transfer mechanism to the collection station ,
The reverse transfer mechanism is
A turntable,
On the surface of the turntable, a cylindrical member that extends radially about the rotation center of the turntable and is supported in a rotatable state by the turntable;
A shaft member extending through the hollow portion of the cylindrical member and rotating integrally with the cylindrical member;
A gripper attached to the outer end of the shaft member, capable of holding the mouth of the preform and blow molded product, and moving along the second annular conveyance path when the turntable rotates,
A rotating cam mechanism that rotates the cylindrical member 180 degrees as the turntable rotates;
An insertion / removal mechanism for inserting / removing the mandrel with respect to the mouth of the inverted preform or blow molded product,
During one turn of the turntable, the preform is inverted to the inverted state, the mandrel is inserted into the mouth of the inverted preform, the mandrel is pulled out from the mouth of the inverted blow molded product, and A blow molding apparatus for performing reversal of an inverted blow molded product to an upright state . In claim 1 ,
The rotating cam mechanism is
First and second cam followers formed on a slider capable of reciprocating in the axial direction of the cylindrical member;
A first cam groove formed on the outer peripheral surface of the cylindrical member in a spiral manner over an angular range of 180 degrees, in which the first cam follower slides;
A second cam groove formed on the surface of the stationary plate and through which the second cam follower slides;
The blow molding apparatus characterized in that the shape of the second cam groove is defined so that the slider reciprocates in the radial direction according to the rotation of the turntable. In claim 2 ,
The gripper includes a pair of open / close claws that can be opened and closed,
And a claw opening / closing mechanism for opening / closing the opening / closing claw,
The claw opening / closing mechanism includes a sliding cam mechanism that slides the shaft member in the axial direction of the cylindrical member, and a link mechanism that converts the sliding of the shaft member into an opening / closing operation of the opening / closing claw. Blow molding equipment. In claim 1 , 2 or 3 ,
The insertion / removal mechanism includes a mandrel support member that can be raised and lowered at a position directly below each gripper, and a lift cam mechanism that raises and lowers the mandrel support member according to the rotation of the turntable. Molding equipment. In any one of claims 1 to 4 ,
The first, second and third transfer mechanisms are:
A turntable,
An annular guide rail fixed on the surface of the turntable so that the center of rotation of the turntable is the center,
A plurality of sliders slidable along the annular guide rail;
A holding part for holding a preform or blow molded product formed on each slider;
On the inner position of the arcuate guide rail in the turntable, swing pins arranged in a freely rotatable state at a predetermined angular interval on a concentric circle centered on the rotation center of the turntable;
A plurality of swing arms that swing along the surface of the turntable around each swing pin as the turntable rotates,
A slidable connecting portion that connects the oscillating end of each oscillating arm to each slider in a slidable manner in the axial direction of the oscillating arm; and
A blow molding apparatus characterized by comprising: In claim 5 ,
A swing cam mechanism for swinging each swing arm with the rotation of the turntable;
The cam mechanism includes an arm extending in a direction orthogonal to each swing pin, a cam follower attached to the tip of the arm, and a fixed plate in which a cam groove is formed to slide the cam follower. Blow molding equipment characterized by

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