JPH0497825A - Cutting device of parison of blow molding machine - Google Patents

Abstract

PURPOSE:To cut parison each in the same lengths always, by a method wherein a cutter is made freely turnable unidirectionally by an actuator and the actuator is provided with a cutter positioning mechanism deciding a starting position of cutting of the cutter. CONSTITUTION:The title device is constituted of a rotary plate 44 where the tip of a rod 42a of an air cylinder 42 is hinged by a pin and turns in a clockwise direction by a movement and reciprocation of the rod 42a, a fitting plate 47 fixed to the lower end of a shaft part 44a, a cutter 48 whose tip fitted to the top of the front of the fitting plate 47 through a plurality of bolts 49 is in a triangular shape and a positioning mechanism 50 of the cutter 48, which is juxtaposed with the air cylinder 42 and rotary plate 44 on a base plate 41 and decides a starting position (starting position of rotation) of cutting of the cutter 48. Then since the title device is constituted so that the cutter 48 does not perform reciprocation but turns unidirectionally through which the upper end of each molten parison is cut off. Therefore, the molten parison 2, 2, 2 each can be cut off always respectively under a fixed state, for example, into a fixed lengths.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a parison cutting device for a blow molding machine for blow molding detergent containers, makeup skin, etc. from a parison.

[Conventional technology]

For example, an extruder that extrudes a parison made of thermoplastic resin vertically downward is provided with a cutter that moves reciprocally using an air cylinder, and this cutter alternately repeats forward and backward movements, allowing the extruder to move from the extruder to the extruder. There is a parison cutting device for a blow molding machine that sequentially cuts the parison extruded into a pair of opening/closing molds disposed below to continuously mold a resin hollow product.

[Problem to be solved by the invention]

However, in the conventional parison cutting device of a blow molding machine, the parison is sequentially cut by reciprocating the cutter using an air cylinder, and the cutting start position is different when the cutter moves forward and backward, so each There was a drawback that the parison could not always be cut to the same length.

Therefore, the present invention provides a parison cutting device for a blow molding machine that can solve the above problems.

[Means to solve the problem]

A mold for sandwiching and blow-molding the parisons is installed below an extruder that extrudes a plurality of parisons, and the parisons are cut by a cutter above the upper surface of the mold. In the parison cutting device of the machine, the cutter is made rotatable in one direction by an actuator, and the actuator is provided with a cutter positioning mechanism for determining the cutting start position of the cutter.

[Effect]

The cutting start position of the cutter is always determined at a constant position by the cutter positioning mechanism, and since the cutter is always rotated in one direction by the actuator, each parison is always cut to the same length.

〔Example〕

Hereinafter, one embodiment of the present invention will be described in detail with reference to the drawings.

In FIG. 1, reference numeral 1 denotes a rotary blow molding machine, which has an extruder 10 that extrudes a tubular molten parison 2 made of thermoplastic resin vertically downward. This extruder 1
A pair of open/close molds 8° are used to hold the molten parison 2 and blow mold it on a turntable 7 which is rotatably supported on a base 5 attached to the base 5 via a support shaft 6 (see FIG. 8). Six sets of molds 8' are mounted on each base plate 9, and each pair of opening/closing molds 8.8' of these six sets is intermittently rotated in the section from station A to station F shown in FIG. By sequentially turning the molten parison 2, the molten parison 2 is made into a molded product 2', which becomes, for example, a detergent container, a cosmetic bottle, etc.
(See Fig. 11) Continuous blow molding can be performed.

As shown in FIGS. 1 to 4, the extruder 10 includes a lower base 11 and an upper base provided on the lower base 11 so as to be pivotable in the horizontal direction with respect to the lower base 11 by a pivot drive mechanism 20. 12, and an extruder main body 13 which is placed on the upper base 12 and reciprocated in the vertical direction by a vertical drive mechanism 30 to supply the molten parison 2 into the pair of opening/closing molds 8° 8' when descending. has been done.

As shown in FIGS. 1 to 4, this extruder main body 13 has a hopper 14 on the upper rear side into which pelletized thermoplastic resin (raw material) is charged, and at the bottom of this hopper 14, A cylinder 18 has a built-in screw 16 that is rotated by a motor 15 or the like, and the outside is heated by a heater (not shown).
have. The thermoplastic resin heated and melted within this cylinder 18 is passed through a tubular push-in die head 19 provided at the tip of the cylinder 18 into three tubular molten parisons 2. 2. 2, a pair of vertically downward opening/closing molds 8
, 8' and are simultaneously extruded and supplied into each of three cavities of the same shape formed in each cavity. Note that the number of molten parisons 2 extruded from the extruder main body 13 is not limited to three, and may be one, two, or four or more.

As shown in FIGS. 1 to 4, the rotation drive mechanism 20 includes guides 21 fixed to four corners of the upper surface of the lower base 11.
, guides 22 fixed to the four corners of the lower surface of the upper base 12 and slidable relative to the guides 21, and a slewing ring bearing (inner bearing) having internal teeth 23a on the inner peripheral surface. 23 is fixed to the upper surface of the lower base 11, and a drive gear 27 fixed to a shaft portion 26a meshes with the inner teeth 23a of the inner bearing 23.

As shown in FIGS. 2 to 4, the vertical drive mechanism 30 includes a pair of hinges 31, 31 provided between the rear part of the upper base 12 and the rear part of the extruder main body 13, and a front part of the upper base 12. A pair of shock absorbers 32.32 are interposed between the front part of the extruder body 13 and a pair of shock absorbers 32.32, and a pair of brackets 33. A link 34, 34, a link 36 whose one end is pivotally supported by a pair of brackets 35, 35 hanging down on the front side of the lower surface of the extruder main body 13, and a bracket 37 which stands up on the upper surface of the upper base 12, swings in the vertical direction. The pair of links 34 are freely supported, and are attached to the U-shaped portion at the tip of the rod 38a.
．． 34 and a hydraulic cylinder 38 pivotally supported to sandwich the other end of the link 36.

Further, the parison cutting device 40, as shown in FIG. .2.2 upper end 2a.

The molds 2a and 2a are each cut to a certain length so that they slightly protrude from the upper surfaces of the pair of opening/closing molds 8 and 8'.

This parison cutting device 40 includes a base plate 41 fixed to the extruder main body 13 and extending horizontally below the front part of the cylinder 18, and a support shaft 43 on the base of the base plate 41 for swinging in the left-right direction. A movably supported air cylinder (actuator) 42 and a shaft portion 44a
the center thereof is fitted into a one-way clutch 46 fixed to the lower surface of the tip of the base plate 41 with a bolt 45,
The tip of the rod 42a of the air cylinder 42 is fixed to a rotary plate 44 which is pivoted by a pin and rotates in one direction (clockwise) by the forward and backward movement of the rod 42a, and the lower end of a shaft portion 44a of the rotary plate 44. mounting plate 47 and this mounting plate 4.
A cutter 48 with a triangular tip is attached to the front upper surface of the cutter 48 via a plurality of bolts 49, etc., and an air cylinder 42 and a rotary plate 44 are provided on the base plate 41, and the cutter 48 has a cutting start position. (Rotation start point position)
The cutter positioning mechanism 50 determines the position of the cutter. The cutter 48 does not reciprocate but rotates in one direction to cut the upper end 2a, 2a, 2a of each molten parison 2.2.2. 2. 2 can be cut in a constant state, for example, to a constant length. Incidentally, the upper end 2a of each molten parison 2 is left as an upper burr 28' (burr at the mouth) on the upper part of the molded product 2' after blow molding.

As shown in FIG. 5.6, the cutter positioning mechanism 50 includes a small air cylinder 51 fixed to a base plate 41 so as to be substantially parallel to the air cylinder 42, and a support shaft 53 mounted on the base plate 41. A pair of links 52.52 are swingably supported on the recess 41a of the base plate 41, and both ends are connected to the pair of links 52.52.
52 and the tip 51 of the rod of the air cylinder 51
The intermediate link 54 is rotatably supported via the support shaft 56 between the tips of the pair of links 52 and 52, and the circular arc-shaped link formed on the outer periphery of the rotating plate 44. It is comprised of a roller 55 that comes into contact with the notch 44b and can freely move away from it to determine the cutting start position (rotation start position) of the cutter 48.

The periphery of the lower surface of the turntable 7 rotatably supported on the base 5 via a support shaft 6 rests on a number of bearings 60 erected on the base 5. The annular driven gear 61 is fixed. This driven gear 61 meshes with a pair of idle gears 62, 62 rotatably supported via respective support shafts 63 erected on the base 5. Further, the pair of idle gears 62, 62 mesh with a drive gear 66 attached to a reduction gear 65 of the AC servo motor 64 on the base 5. This drive gear 66 and the turntable 7
a pair of idle gears 62 between the driven gear 61 on the outer periphery of the
, 62, it is possible to eliminate backlash between the respective gears, and the intermittent rotation of the turntable 7 and positioning when stopped can be performed with high precision.

Further, as shown in FIGS. 1 and 8, a mouth-shaped gate frame 67 is erected from the station B position of the turntable 7 on the base 5 to the station E position so as to straddle the turntable 7. be.

Further, at the position of station F of the turntable 7 on the base 5, a molded product storage container 68 and a chute 69 for storing the taken out molded products 2' are provided upright. At the station B of the turntable 7 of the gate frame 67, a pair of opening/closing molds 8, 8' is provided with a parison for correcting the upper end 2a of the unsolidified molten parison 2 protruding above the upper surface thereof into a flat standing state. A shape modification mechanism 70 is provided. Further, between the upper frame 68a and the middle frame 68b that protrude above the turntable 7 of the molded product storage device 68, when the pair of opening/closing molds 8.8' are opened after the hollow molding, the molded product 2' After gripping and raising the upper burr 28', a molded product take-out device 80 is provided which sucks the upper burr 2a' of the molded product 2' and takes it out while gripping the body 2b'.

As shown in Figs.
Four guide bolts 73. whose tips are fixed by nuts 72 to a bracket 71 fixed above the middle of a pair of opening/closing molds 8.8' are suspended. ...and the opening-shaped mounting plate 7 attached to the lower end of each guide bolt 73.
4, and the rack passes through and slides a pair of guide shafts 75.75 that are passed on both sides 74a, 74a of this mounting plate 74, and solidifies the molds 8.8' to protrude above the upper surfaces of the pair of opening/closing molds 8.8'. Each melted parison in front 2. 2. 2 upper ends 2a, 2a,
a pair of clampers 76, 76 for clamping 2a to correct it to a flat standing state; and both sides 7 of the mounting plate 74.
4a, 74a, each rod 77a
a pair of air cylinders 77 .
It consists of 7.

Further, as shown in FIG. 11, the molded product take-out device 80 is disposed on the upper frame 68a of the molded product storage container 68, and when the pair of opening/closing molds 8.8' are opened after blow molding,
An upper burr gripping and extraction mechanism 81 that grips and raises the upper burr 2a of each molded product 2' and an upper burr gripping and extraction mechanism 81 that is disposed on the middle frame 68b of the molded product storage container 68 and that is raised by the upper burr gripping and extraction mechanism 81. a suction gripping and conveying mechanism 90 that suctions the upper burr 2a' of each molded product 2', grips the body 2b' and rotates 180 degrees to store the molded product 2' in the molded product storage container 68; It consists of

As shown in FIGS. 11 to 14, the upper burr gripping and extraction mechanism 81 includes an air cylinder 82 erected on the tip side of the upper frame 68a of the molded product storage device 68, and a rod 82a of the air cylinder 82. fixed at the tip of the rod 82
A substantially square-shaped mounting plate 83 that moves vertically by expansion and contraction of a, and both side parts 83a, 8 of this mounting plate 83.
3b, the rack passes through a pair of guide shafts 84 and 84.

Molded product 2 from inside the pair of opening/closing molds 8, 8' when sliding and opening
A pair of chucks 85.8 that grip the upper burr 2a/
6 is attached to the center of the inner surface of one side 83a of the mounting plate 83, and the tip of the rod 87a is connected to one chuck 8.
An air cylinder 87 is fixed at the center of the mounting plate 83, and an air cylinder 87 is mounted on both sides of the outer surface of one side 83a of the mounting plate 83, and the tips of each rod 88a are fixed to both sides of the other chuck 85. It is composed of three chuck pieces 89 and a pair of air cylinders 88 and 88 that bring the one chuck 86 into contact with and separate from them. And the rods 87g and 8 of each of the air cylinders 87 and 88 are
8a causes the three chuck pieces 89 of one chuck 85 and the other chuck 86 to remove the upper burr 2 of the molded product 2'.
Holding the upper end of a', remove the rod 82 of the air cylinder 82.
A pair of opening/closing molds 8 when the molded product 2' is opened due to the leaving of work of a.
8 and the upper frame 6 of the molded product storage container 68.
It is designed to be raised to a predetermined position below 8a.

As shown in FIGS. 11.15 to 17, the suction gripping and conveying mechanism 90 includes a pair of arms 91.91 that rotate every 180 degrees by a motor 92 that is installed upright on the middle frame 68b of the molded product storage device 68. A slide frame 94 is provided on both sides of the front end of each arm 91 so as to be slidable in the front and back direction along a pair of guide shafts 93 and 93, and the tip of a rod 95a is fixed to this slide frame 94. , an air cylinder 95 that reciprocates the slide frame 94 in the front and back direction by the forward and backward movement of the rod 95a, and an air cylinder 95 that is attached to the upper front surface of the slide frame 94 at an equal distance apart, and vacuums the upper burr 2a' of the molded product 2'. Three suction pads 96 for suction, and three sets of air cylinders 98 that are attached at equal distances apart from each other on the lower front side of the slide frame 94 and that grip and release the grip on the body 2b' of the molded product 2'. 91 and 91, respectively. still,
Reference number 99 in FIG. 11 is a proximity switch, and each proximity switch 99 opens each of the suction pads 96 and each pair of gripping pieces 97 and 97 provided at each front end of the pair of arms 91.91. A pair of opening/closing molds 8.8'
The rotational positions of the pair of arms 91 and 91 are determined so that they are located above the chute 69 of the molded product storage container 68, respectively.

60° on the turntable 7 through six base plates 9
Each of the six sets of opening/closing molds 8.8' arranged at intervals
It can be opened and closed freely by a mold clamping device 100 shown in Fig. 8.18. This mold clamping device 100 consists of three support blocks 102 that stand upright at the center of the base plate 9 at an equal distance apart.
A pair of guide shafts 101, 101 fixed so as to be parallel to each other in the horizontal direction via
A pair of movable plates 103.101 are slidably provided, and each of the molds 8, 8' is fixed to opposing surfaces thereof.
103', a pair of clamp rods 104 and 104', one end of which is fixed to the back side of each of the movable plates 103 and 103', for bringing the molds 8 and 8' into contact with each other and separating them from each other; It is swingably supported by a bracket 106 erected at one end (outside) via a pivot 107 located below the height of each of the guide shafts 101 and 101, and the other end of one of the clamp rods 104' is attached to the upper end. intermediate link 108
A swinging lever 10 is pivotally supported by a pin through the base plate 9 and has a lower end projecting downward from the upper surface of the base plate 9 through an opening 9a.
5, and a pair of blocks 109.10 below the base plate 9.
an intermediate link 108 which is slidably supported via an intermediate link 9 and whose one end is pivotally supported by a pin to the other end of the clamp rod 104' of the swing lever 105 via an intermediate link 111;
A slide rod 110 is pivotally supported by a pin at a lower end spaced apart from the other end by a distance equal to the distance between the pivot shaft 107, and the slide rod 110 and the other clamp rod 104 are connected through the opening 9b of the base plate 9. A bracket 1 that connects the ends and stands up on the other end (inside) of the base plate 9
13, and a pair of hydraulic cylinders (actuators 114 and 115) suspended at positions corresponding to stations A and F of the gate frame 67, the connecting plate 112 is made reciprocally movable, and this One hydraulic cylinder 114 moves the connecting plate 112 forward to close the pair of opening/closing molds 8, 8', and the other hydraulic cylinder 115 moves the connecting plate 112 backward to close the pair of opening/closing molds. The toggle mechanism 120 maintains the 8° 8' open and deflected state.

This toggle mechanism 120 is rotatably supported in the vertical direction via a support shaft 122 by a bracket 113 that stands up on the other end (inside) of the base plate 9, and one end is attached to the other hydraulic cylinder 1.
The first link 121 is pressed by the first link 15 and the other end springs upward; The roller 124 is slid along the opening 113a of the bracket 113, and when the other end of the first link 121 springs upward, the connecting plate 112 is moved back, and the roller 124 is rotatably supported at one end. and a second link 123 that is pressed by one of the hydraulic cylinders 114 to move the connecting plate 112 forward.

The procedure for blow molding a molten parison 2 by intermittently rotating each pair of open/close molds 8, 8' from station A to station F using the rotary blow molding machine 1 of the embodiment will be described above.

First, it is opened at station F as shown in Figure 18,
A pair of open/close molds 8, 8' from which each molded product 2' has been taken out by the molded product take-out device 80 rotates to station A. Therefore, when the AC servo motor 64 is stopped and the pair of opening/closing molds 8, 8' are stopped at station A, the pair of opening/closing molds 8, 8' are replaced with each other that has already been extruded to a predetermined length. It is closed by the mold clamping device 100 so as to sandwich the molten parisons 2, 2.2. That is, the roller 124 of the second link 123 of the mold clamping device 100 is pressed downward by the hydraulic cylinder 114, and the connecting plate 112 moves outward (radially outward of the turntable 7) on the base plate 9 ( go).

Due to this forward movement of the connecting plate 112, one clamp rod 104 pushes one mold 8 in the closing direction, and the other clamp rod 104' can freely slide)'110.
Intermediate link 111. Swing lever 105, intermediate link 10
8 in the opposite direction to one of the clamp rods 104 to push the other mold 8' in the closing direction. As a result, the pair of opening/closing molds 8.8' are instantly closed so as to sandwich the three molten parisons 2.2.2.

Almost simultaneously with the clamping of the pair of opening/closing molds 8, 8', the rod 42a of the air cylinder 42 of the parison cutting device 40 moves back and forth, causing the cutter 48 to rotate at high speed in the direction of the arrow in FIG. , the above three melted parisons 2.2.
2 are instantly cut off. The cutter 48 is rotated in one direction by the one-way clutch 46 to cut each molten parison 2.2.
2 can be cut in a constant state, for example, to always have the same constant length. This makes it easy to monitor the cutting length of each melted parison 2.2.2 and to perform wide six-way control by processing the data.

Further, since the cutting start position of the cutter 48 is always positioned at the position shown by the solid line in FIG. 5 by the cutter positioning mechanism 50, the effect of always cutting each molten parison 2.2. Ru.

At approximately the same time as each molten parison 2, 2.2 is cut, the die head 19 side of the extruder main body 13 of the extruder 10 is moved by a pair of hinges 31.31 by the vertical drive mechanism 30, as shown in FIG. It rotates upward as a center and rises. As a result, when the pair of opening/closing molds 8,8' rotate to the next station B, each molten parison 2. 2
．． 2 will not interfere with each other. A pair of opening/closing molds 8, 8
' and each melted parison during extrusion2. 2. When the extruder body 1 of the extruder 10 rotates to a position where it does not interfere with the
As shown in FIG. 2, the die head 19 side of No. 3 rotates downward around the pair of hinges 31.3.1 due to the withdrawal of the rod 38a of the hydraulic cylinder 38 of the vertical drive mechanism 30, and the next When the pair of opening/closing molds 8.8' stay at station A, each melting parison 2, 2.2
The die head 1 is extruded to a predetermined length.
3 melted parisons from 9 2. 2. Continue to push out 2 continuously.

Next, by driving the AC servo motor 64 and repeating the intermittent rotation and stopping every 60 degrees from station B to station E with the pair of open/close molds 8 and 8' closed, the above-mentioned A pair of opening/closing molds 8.8'
Compressed air is blown into each of the above-mentioned molten parisons 2 held between a pair of open/close molds 8.8' by a blow needle (not shown) built into the molten parison, and the parisons 2 are blow-molded into a predetermined shape. The molded product 2' is cooled in a pair of open/close molds 8, 8'.

In this pair of opening/closing molds 8, 8', the compressed air blowing device is not a blow bin but a blow needle.
Molded product 2' cannot be removed using a blow pin. Therefore, at the station B, the upper ends 2a, 2a, 2a of each molten parison 2, 2.degree. The clampers 76 and 76 respectively clamp each melted parison 2. 2. 2 upper end 2a
2a, 2a are corrected to a flat, upright state, so that the molded product 2' can be easily taken out from the pair of opening/closing molds 8° 8' by a molded product taking-out device 80, which will be described later.

In addition, each section from station A to station F has a large diameter (for example, 2700 mm) and a high weight (approximately 10 mm).
The turntable 7 is powered by an AC servo motor 64.
Drive gear 66, pair of idle gears 6:2.62. A turntable drive device consisting of a driven gear 61 etc. rotates intermittently at high speed (for example, 2.5 seconds) (for example, 6 seconds).
The pair of opening/closing molds 8.8' are successively rotated intermittently. Further, a pair of idle gears 62, 6 are provided between an annular driven gear 61 fixed to the outer periphery of the turntable 7 and a drive gear 66 that transmits the rotation of the AC servo motor 64.
2, it is possible to eliminate backlash between each gear. Thereby, the rotation of the turntable 7 and the positioning when stopped can be performed with higher precision.

When the pair of opening and closing molds 8 and 8' come to station F, the pair of chucks 85 and 86 of the upper burr gripping and extraction mechanism 81 of the molded product extraction device 80 have already been lowered, so that the pair of opening and closing molds 8 and 8' have already been lowered. 8. The upper burr 2a' of the molded product 2', which protrudes from the upper surface of 8' and has been corrected to a flattened state by the burr shape correction mechanism 70, is gripped by each chuck piece 89 of the chuck 85 and the chuck 86. At approximately the same time as this gripping, the mold clamping device 100 is operated by the hydraulic cylinder 115 to open the pair of opening/closing molds 8.8'. Then, by retracting the rod 82a of the air cylinder 82 of the upper burr gripping and extraction mechanism 81, the pair of chucks 85 and 86 are raised to the suction gripping and transporting mechanism 90. When the molded product 2' is lifted up by the upper burr gripping and extraction mechanism 81, each suction pad 96 provided on one arm 91 of the suction gripping and conveying mechanism 90 moves the mold Upper burr 2 of item 2'
The portion directly below the pair of chucks 85, 86 of a' is reliably vacuum-sucked, and the body 2b' is securely held by each pair of gripping pieces 97, 97 without shaking the molded product 2'. Next, the arm 91 is rotated 180' by the motor 92 to release the suction and gripping state, so that each of the finished molded products 2' is stored in the molded product storage container 68, respectively.

Opening of the pair of opening/closing molds 8° 8' by the mold clamping device 100 is performed by moving the connecting plate 112 in the opposite direction to the mold clamping (backward movement).

The pivot shaft 107 of the swing lever 105 of this mold clamping device 100 is located below the height of the pair of guide shafts 101, 101, and from this pivot shaft 107, the clamp rod 104'
The distance to the bin pivot point of the intermediate link 108 at the other end;
Intermediate link 11 of slide rod 110 from pivot 107
Since the distance to the pin pivot point 1 is made equal, and the pivot shaft 107 is provided between the position of the pair of guide shafts 101 and the top surface of the base plate 9, the mold clamping force of the mold clamping device 100 is reduced. can be equally divided between the pair of guide shafts 101, 101 and the base plate 9, and no unreasonable load is applied to the plywood 9 or the like. Furthermore, the opened and closed states of the pair of opening/closing molds 8, 8' can be reliably maintained by the toggle mechanism 120, which has a simple structure and includes a first link 121, a second link 123, and the like.

In addition, when the screw 16 of the extruder 10 is taken out for cleaning after the blow molding is completed by the rotary blow molding machine 1, the extruder 10 is placed against the tar table 7 as shown by the two-dot chain line in FIG. The extruder main body 13 can be rotated by a predetermined angle by a rotation drive mechanism 20. This prevents the extruder main body 13 from interfering with the mold clamping device 100 and the like, making cleaning of the screw 16 and the like easier. Further, since the extruder main body 13 is of a rotating type, the installation space of the rotary blow molding machine 1 can be saved.

According to the embodiment, the extruder 10 of the rotary blow molding machine 1 is connected to the pair of hinges 31.3 by the vertical drive mechanism 30.
Although the extruder 10 is provided to be movable up and down centering on the extruder 1, the extruder 10 is not limited to this, and the extruder 10 of another embodiment shown in FIG.
', the position of the pair of hinges 31', 31' is reversed V.
The height of the die head 19 may be set to the height of the die head (on the same horizontal plane) via the letter-shaped frame 3. Thereby, vibration of the die head 19, misalignment of the parison 2, etc. can be reliably solved. Note that other configurations are the same as those in the previous embodiment, so the same reference numerals are given and detailed explanations are omitted.

〔Effect of the invention〕

As described above, according to the present invention, in the parison cutting device of a blow molding machine, the cutting start position of the cutter is always determined at a constant position by the cutter positioning mechanism, and the cutter is always rotated in one direction by the actuator. This allows each parison to always be cut to the same length.

[Brief explanation of the drawing]

Fig. 1 is a plan view of a rotary blow molding machine showing an embodiment of the present invention, Fig. 2 is a side view of an extruder of the blow molding machine, Fig. 3 is a front view of the extruder, and Fig. 4 is a rear view of the same extruder,
Figure 5 is a plan view of the parison cutting device of the same blow molding machine;
Figure 6 is a sectional view taken along the line ■-■ in Figure 5, Figure 7 is a side view showing a part of the parison cutting device in cross section, and Figure 8 is a side view of the mold clamping device of the blow molding machine. , FIG. 9 is a front view of the burr shape correction mechanism of the same blow molding machine, FIG. 10 is a plan view of the burr shape correction mechanism of the same blow molding machine, FIG. The figure is a side view of the upper burr gripping and extraction mechanism of the molded product extraction device of the same blow molding machine, Figure 13 is a sectional view taken along the xm-xm line in Figure 12, and Figure 14 is a front view of the upper burr gripping and extraction mechanism of the same blow molding machine. , Fig. 15 is a plan view of the suction gripping and transporting mechanism of the molded product take-out device, Fig. 16 is a side view of the suction gripping and transporting mechanism, Fig. 17 is a front view of the suction gripping and transporting mechanism, and Fig. 18 is the same. FIG. 19 is an enlarged side view of a mold clamping device of a blow molding machine, and FIG. 19 is a side view of an extruder of another embodiment. ■... (rotary) blow molding machine, 2... (melting) parison, 8.8'... (pair of opening and closing) molds, 10...
・Extruder, 40... Parison cutting device, 42... Air cylinder (actuator), 48... Cutter
50... Cutter positioning mechanism. T-"T U Figure 3 Figure 9 Figure 10 Figure 11

Claims (1)

[Claims] (1) A mold for sandwiching and blow-molding the parisons is installed below an extruder that extrudes a plurality of parisons, and a cutter cuts the parisons above the upper surface of the mold. In the parison cutting device for a blow molding machine, the cutter is rotatable in one direction by an actuator, and the actuator is provided with a cutter positioning mechanism for determining a cutting start position of the cutter. Parison cutting device.