Title of Invention

INJECTION STRETCH BLOW MOLDING APPARATUS

Abstract

An injection stretch blow molding apparatus 50 has an injection molding section 68, a stretch blow molding section 70 and a rotary disc 66 for intermittently conveying neck molds 90 to the respective injection molding section and stretch blow molding section. The apparatus further includes a lower base 54 fixedly mounted on a machine bed 52, an upper base 56 disposed above the lower base 54 for supporting the rotary means 66 and a traction plate 58 disposed below the lower base 54 within the machine bed 52. The upper base 56 and traction plate 58 are connected to each other through a plurality of tie bars 62 extending through the lower base 54. The machine bed 52 further includes a neck mold clamping cylinder 12 0 for moving the traction plate 58 in the vertical direction.

Full Text

INJECTION STRETCH BLOW MOLDING APPARATUS BACKGROUND OF THE INVENTION Field of the Invention The present invention relates to an injection stretch blow molding apparatus and particularly to an injection stretch blow molding apparatus of a type that comprises a rotary means for intermittently conveying neck molds at least to an injection molding section and a stretch blow molding section. Description of the Related Art Such an injection stretch blow molding apparatus can be found, for example, in Japanese Patent Publication No. 5-32211. As shown in Fig. 4, this injection stretch blow molding apparatus comprises various molding sections such as an injection molding section 12, a stretch blow molding section 14 and so on, all of which are disposed on a machine bed 10 in place. The machine feed 10 comprises a lower base 16 fixedly mounted thereon and a support plate 20 fixedly mounted on the lower base 16 through tie bars 18. Between the lower base 16 and the support plate 2 0 are located an upper base 22 and clamping plate 24 which are vertically movable along the tie bars 18. The underside of the upper base 22 carries a rotary disc 26 for intermittent rotation. The rotary disc 26 comprises neck molds 28 disposed thereon at positions corresponding to the respective molding sections. 1 Each of the neck molds 28 can be moved and stopped to the corresponding one of the molding sections through intermittent rotation of the rotary disc 26. The injection molding section 12 comprises an injection cavity mold 30 while the stretch blow molding section 14 comprises a blow cavity mold 32. The lower base 16 comprises an elevator cylinder 34 mounted thereon. When the elevator cylinder 34 moves the rotary disc 26 and upper base 22 in the downward direction, each of the neck molds 28 will close the corresponding one of the injection and blow cavity molds 30, 32. The clamping plate 24 comprises an injection core mold 3 6 corresponding the injection molding section 12 and a blow core mold 38 corresponding to the stretch blow molding section 14 . When the clamping plate 24 is downwardly moved by a clamping cylinder 40 on the support plate 20, the injection core mold 36 and blow core mold 38 as well as the neck molds 28 will be clamped against the injection and blow cavity molds 30, 32, respectively. The clamping plate 24 includes a stretch-rod elevator cylinder 44 mounted thereon at a position corresponding to the stretch blow molding section 14 , the stretch- rod elevator cylinder 44 being operative to move a stretch rod 42 back and forth. In such an injection stretch blow molding apparatus, the injection core mold 36, blow core mold 38 and neck molds 28 are driven and clamped by the clamping cylinder 40 on the support plate 20 which is located above the clamping plate 24. Thus, the clamping cylinder 40 must apply an increased clamping force to these components. Moreover, the clamping plate 24 has to be moved from 2 the position directly below the support plate 20 to other positions adjacent to the injection and blow cavity molds 30, 32. This requires an increased stroke of movement. As a result, the clamping cylinder 40 will be increased in size and weight. Further, the length of the cylinder will also increase the whole height of the apparatus. Moreover., the heavy structure located on the top of the apparatus makes the blow molding machine very unbalanced and unstable. Since the elevator cylinder 34 for vertically moving the upper base 22 is located substantially at the center of the lower base 16, moreover, the blow stroke of the blow damping cannot be increased due to the presence of the elevator cylinder 34. This makes the maintenance difficult. Prior art EP0288581 for injection blow molding machine is referred herein wherein unlike the lip retainer plates being connected to the lower end of vertical shafts as contemplated in the said prior art is quite different from the present invention in which the neck molds being arranged on the rotary means; unlike an injection core mold clamping cylinder is provided within the machine bed as defined in the said prior art, in the present invention an injection core mold clamping cylinder is provided above the upper base for vertically moving an injection core mold; other distinguishing features of the present Invention such as a plurality of tie bars connecting the upper base to the traction plate and a clamping means provided within the machine bed for vertically moving the traction plate are absent in the said prior injection blow molding machine. Prior art reference is drawn to another patent document EP0497700 for injection blow molding machine is referred herein wherein unlike the sectorial plates vertically move as contemplated in the said prior art is quite different from the present invention in which an upper base support the rotary means; 3 unlike an injection core mold clamping cylinder is provided within the machine bed as defined in the said prior art, in the present invention an injection core mold damping cylinder is provided above the upper base for vertically moving an injection core mold; Other distinguishing features of the present invention such as a plurality of tie bars connecting the upper base to the traction plate and a clamping means provided within the machine bed for vertically moving the traction plate are absent in the said prior injection blow molding machine. SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide an injection stretch blow molding apparatus which has a reduced whole height and is more compact and balanced but does not have any obstruction on the center of the lower base. To this end, the present invention provides an injection stretch blow molding apparatus comprising: A machine bed; An injection molding section provided on the machine bed for injection molding a preform; A stretch blow molding section provided on the machine bed for stretch blow molding the preform into a container; A rotary means for intermittently conveying neck molds to 4 the respective injection molding section and stretch blow molding section, the neck molds being arranged thereon at positions corresponding to the respective injection molding section and stretch blow molding section; a lower base fixedly mounted on the machine bed; an upper base provided above the lower base to support the rotary means; a traction plate provided below the lower base within the machine bed; a plurality of tie bars slidably extending through the lower base and connecting the upper base to the traction plate; and clamping means provided within the machine bed for vertically moving the traction plate. In one aspect of the present invention, the tie bars slidably extending through the lower base connect the upper base to the traction plate. When the traction plate is vertically moved by the clamping means in the machine bed, the upper base can be moved vertically along the tie bars to open, close and clamp the molds. As a result, it is possible to provide a balanced and stable injection stretch blow molding apparatus which can minimize the whole height of the system without disposing any large clamping means above the machine bed. Moreover, since the clamping means vertically moves the upper base by towing the traction plate, it is unnecessary to provide a support plate which is fixed above the upper base. This provides a very compact apparatus. Furthermore, since the upper base is vertically moved by 5 the clamping means disposed within the machine bed, it is unnecessary to provide any means for vertically moving the upper base such as the elevator cylinder 34 shown in Fig. 4 on the lower base. Thus, a sufficient stroke of blow cavity mold opening and closing can be ensured in the stretch blow molding section. Moreover, the maintenance can be facilitated on the lower base without any interference. In another aspect of the present invention, a cylinder fixing plate for mounting an injection core mold clamping cylinder is disposed above the upper base. The cylinder fixing plate, upper base and traction plate are fixedly secured to the tie bars and vertically movable as a unit. In such an arrangement, the distance between the cylinder fixing plate and the upper base can be maintained constant. Thus, the stroke of the injection core mold clamping cylinder can be minimized to reduce the dimensions thereof. Providing the injection core mold clamping cylinder enables the clamping means in the machine bed to be used exclusively for the neck molds. Since the clamping means functions separately from the injection core mold clamping cylinder, the respective clamping sections can be made compact. In still another aspect of the present invention, the clamping means may be provided at a position below the injection molding section. In such a case, it is possible to generate an increased clamping force at the injection molding position at which a higher clamping force is required compared to other sections such as the 6 stretch blow molding. Thus, the clamping force in the clamping means can be minimized. In this case, furthermore, an auxiliary clamping cylinder for vertically moving the traction plate may be disposed below the stretch blow molding section within the machine bed. In such an arrangement, the auxiliary clamping cylinder can receive, with an improved balance, the reaction of blow molding acting on the neck and blow core molds in the stretch blow molding section. According to the present invention, there may be provided synchronizing means for synchronizing the operations of the clamping means and auxiliary clamping cylinder, the synchronizing means being provided within the clamping plate. Even though there are two drive cylinders for moving the traction plate, the synchronizing means can cause the traction plate and upper base to move smoothly in the vertical direction while maintaining them horizontal. In a further aspect of the present invention, a stopper for limiting the lowermost position of the upper base may be provided on the side of the blow molding section. In such an arrangement, even when the blow mold is opened, it is possible to limit the lowermost position of the upper base that moves downwards to ensure the positioning. A further aspect of the present invention provides an injection stretch blow molding apparatus comprising: a machine bed; an injection molding section provided on the machine bed for injection molding a preform; a stretch blow molding section provided on the machine bed for stretch blow molding the preform into a container; a rotary means for intermittently conveying neck molds to the respective injection molding section and stretch blow molding section, the neck molds being arranged thereon at positions corresponding to the respective inj ection molding section and stretch blow molding section; a lower base fixedly mounted on the machine bed; an upper base provided above the lower base to support the rotary means; a traction plate provided below the lower base within the machine bed; a plurality of tie bars slidably extending through the lower base and connecting the upper base to the traction plate; a clamping cylinder provided below the injection molding section within the machine bed for vertically moving the traction plate; an auxiliary clamping cylinder provided below the stretch blow molding section within the machine bed for vertically moving the traction plate; and synchronizing means provided within the machine bed for synchronizing operations of the clamping cylinder and auxiliary clamping cylinder. According to a further aspect of the present invention, it is possible to minimize the whole height of the apparatus and make the apparatus balanced and stable through driving the traction 8 plate by the clamping cylinder below the injection molding section within the machine bed, without disposing the clamping cylinder above the machine bed. Moreover, since there is no obstruction at the center of the lower base, a sufficient stroke of blow mold opening and closing can be provided. This can also facilitate the maintenance of the apparatus. The driving force in the clamping cylinder can be used more effectively for the injection molding section which requires an increased clamping force. Since the auxiliary clamping cylinder for vertically moving the traction plate is disposed below the stretch blow molding section within the machine bed, the upper base can be moved vertically in a balanced manner on both the side of injection molding section and that of the stretch blow molding section. The aforementioned synchronizing means may comprise: two racks extending downwards from the lower base at respective positions corresponding to the injection and stretch blow molding sections; a rotating shaft provided extending between the injection molding section and the stretch blow molding section and vertically movable with the traction plate; and two pinions fixedly mounted on the rotating shaft and each of which is engaged with corresponding one of the two racks. The synchronizing means for the two clamping cylinders includes the rotating shaft which is movable with the traction plate and have two pinions each engaging the corresponding one 9 of the two racks which extend downwards from the lower base. Therefore, this ensures the traction plate to move up and down from the side of the injection molding section to the side of the stretch blow molding section. It is possible to maintain the horizontal level of the upper base that is particularly important when the mold is closed. As a result, the two clamping cylinders can be synchronized, without making the structure of the synchronizing means complicated. BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS Fig. 1 is a plan view of an injection stretch blow molding apparatus according to one embodiment of the present invention. Fig. 2 is a front view, partially broken away, of the injection stretch blow molding apparatus of Fig. 1. Fig. 3 is a cross-sectional view taken along a line III-III in Fig. 1. Fig. 4 is a cross-sectional view of an injection stretch blow molding apparatus according to the prior art. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT One embodiment of the present invention will now be described in detail with reference to the drawings. Figs. 1 to 3 show an injection stretch blow molding apparatus according to one embodiment of the present invention. As shown in Figs. 2 and 3, the injection stretch blow molding apparatus 50 comprises a machine bed 52, a lower base 54, an upper base 56, a traction plate 58 and a cylinder fixing plate 60. The 10 upper base 56, traction plate 58 and cylinder fixing plate 60 are fixedly connected together through a plurality (e.g., four) of tie bars 62 (see Fig. 1) which extend through the lower base 54. The machine bed 52 is of a hollow box-shaped member. An injection device 64 is mounted on one side and at the top of the machine bed 52. The lower base 54 is fixedly mounted on the opposite side and at the top of the machine bed 52. The upper base 56 is located above the lower base 54. The underside of the upper base 56 rotatably carries a rotary disc 66. The upper base 56 is fixedly connected to the middle of two tie bars 62 on the side of the injection device 64 and the top ends of the remaining two tie bars 62 on the opposite side of the injection device 64. A space between the lower base 54 and the rotary disc 66 is used for molding. Within this space, as shown in Fig. 1, an injection molding section 6 8 is provided on the side of the injection device 64; a stretch blow molding section 70 is provided on the opposite side of the injection molding section 68; and a temperature adjusting section 72 and removing section 74 are provided between the injection molding section 66 and the stretch blow molding section 70. In the injection molding section 68, as shown in Fig. 2, an injection cavity mold 78 is mounted on the lower base 54 through a hot runner 76 which nozzle-touches the injection device 64. In the stretch blow molding section 70, as shown in Fig. 2, a blow cavity mold 84 is mounted on the lower base 54. The blow 11 cavity mold 84 is formed by two split molds which can be clamped by a blow mold clamping mechanism 82 including a blow mold clamping cylinder 80. In the temperature adjusting section 72, as shown in Fig. 3, a temperature adjusting pot 86 is fixedly mounted on the lower base 54. In the removing section 74, as shown in Fig. 3, a chute 88 used to remove products from the apparatus (which is omitted in Fig. 2) is mounted on the lower base 54. The underside of the rotary disc 66 carries a plurality (e.g., two) of neck molds 90 which are located at positions corresponding to the injection molding section 68, temperature adjusting section 72, stretch blow molding section 70 and removing section 74, respectively. Each of the neck molds 90 is formed by two split molds, each of which is mounted on one neck-mold support plate 92. When these neck-mold support plates 92 are opened or closed, the respective neck mold 90 will be opened or closed. The rotary disc 66 can be rotated intermittently by 90 degrees through an electric motor 94 which is mounted on the upper base 56. Thus, the neck molds 90 are sequentially conveyed to the injection molding section 68, temperature adjusting section 72, stretch blow molding section 70 and removing section 74. In this embodiment, the stop position of the rotary disc 66 is positioned by a positioning mechanism 96. The stop position may be established only by positioning means such as a servo-motor. On the upper base 54 are disposed a temperature adjusting 12 core moving cylinder 98 for vertically moving a temperature adjusting core (not shown) at a position corresponding to the temperature adjusting section 72 , a blow core mold moving cylinder 102 for vertically moving a blow core mold 100 at a position corresponding to the stretch blow molding section 70 and a stretch-rod elevator cylinder 106 for vertically moving a stretch rod 104. At a position corresponding to the removing section 74, there is further provided an eject cam elevator cylinder 110 for vertically moving an eject cam 108 used to open the neck-mold support plates 92. The cylinder fixing plate 60 is fixedly mounted on the top end of the two tie bars 62 on the side of the injection molding section 68 above the upper base 56. Between the cylinder fixing plate 60 and the upper base 56 is located an injection core mold clamping plate 114 including an injection core mold 112 mounted thereon. The injection core mold clamping plate 114 is mounted for vertical movement along the two tie bars 62. An injection core mold clamping cylinder 116 is mounted on the cylinder fixing plate 60. The injection core mold clamping cylinder 116 includes a piston 118, the tip of which is connected to the injection core mold clamping plate 114. The traction plate 58 is fixedly connected to the bottom ends of the four tie bars 62 within the machine bed 52. On this traction plate 58 is mounted a neck mold clamping cylinder 120 below the injection molding section 68, the neck mold clamping cylinder 120 functioning as clamping means . The neck mold clamping cylinder 120 includes a piston 122 which is connected 13 to the underside of the lower base 54. Therefore, as shown in Fig. 3 when the neck mold clamping cylinder 120 is actuated in a state in which the traction plate 58 is in its upper position, the traction plate 58 descends to tow the tie bars 62 downwards. Thus, as shown in Fig. 2, the upper base 56 connected to the tie bars 62 is also moved downwards by a stroke L1, so that the neck molds 90 mounted on the rotary disc 66 descends. At this point, for example, the neck mold 90 may be clamped against the injection cavity mold 78 in the injection molding section 68. In the side of the stretch blow molding section 70, the underside of the upper base 56 abuts a stopper 138 on the top of the blow mold clamping mechanism 82. Thus, the upper base 56 will be positioned at the lowermost position. In the temperature adjusting section 72, the neck mold 90 is clamped against the temperature adjusting pot 86. In the stretch blow molding section 70, the blow cavity mold 84 is clamped by the blow mold clamping mechanism 82. As the upper base 56 moves downwards, the cylinder fixing plate 60 fixedly connected to the top ends of the two tie bars 62 on the side of the injection molding section 68 is also moved downwards by the same stroke L1 as in the upper base 56. In such a state, the injection core mold clamping cylinder 116 in the injection molding section 68 moves the injection core mold clamping plate 114 downwards by a stroke L2. As a result, the injection core mold 112 and neck mold 90 are clamped so that a molten resin can be injected from the injection device 64 into 14 the injection cavity mold 78 to mold a preform 124. In such a case, the injection core mold clamping cylinder 116 descends together with the upper base 56 which moves downwards . Thus, the distance between the injection core mold clamping cylinder 116 and the upper base 56 can be maintained constant at all times. Therefore, the downward stroke L2 of the injection core mold clamping cylinder 116 may be the minimum stroke necessary to open or close the injection core mold 112. Thus, the length of the injection core mold clamping cylinder 116 can be reduced. And yet, the elevator cylinder clamping cylinder 116 is sufficient to provide a clamping force for clamping only the injection core mold 112. The elevator cylinder clamping cylinder 116 may be relatively small. Thus, the whole height of the injection stretch blow molding apparatus 50 can be minimized and yet the upper weight thereof can be minimized to improve the balance thereof. This makes the injection stretch blow molding apparatus 50 more stable. Since the neck mold clamping cylinder 120 is sufficient to provide a clamping force matching that of the neck molds 90, the neck mold clamping cylinder 120 may be relatively small. In addition, since the neck mold clamping cylinder 120 is disposed below the injection molding section 68, the clamping force of the neck mold clamping cylinder 120 can be used more effectively even though it is relatively small. When the injection molding section 68 performs its molding step, the temperature adjusting section 72 adjusts the temperature 15 of the preform 124 by inserting the temperature adjusting core (not shown) into the temperature adjusting pot 86 by the operation of the temperature adjusting core elevator cylinder 98. In the stretch blow molding section 70, the blow core mold elevator cylinder 102 moves the blow core mold 100 downwards so that the blow core mold 100 will be clamped against the corresponding neck mold 90. With such an operation, the stretch-rod elevator cylinder 106 moves the stretch rod 104 downwards while a blow air is supplied into the blow cavity mold 84. Thus, the temperature adjusted preform 124 will be biaxial stretching blow molded into a bottle 126. In the removing section 74, the eject cam elevator cylinder 110 moves the eject cam 108 downwards so that the neck mold 90 will be opened through the neck-mold support plates 92. Therefore, the molded bottle 126 falls onto the chute 88 from which the bottle 126 will be expelled externally. After the respective molding steps has finished, the blow mold clamping mechanism 82 opens the blow cavity mold 84 while the neck mold clamping cylinder 120 moves the upper base 56 upwards. Furthermore, the injection core mold clamping cylinder 116, temperature adjusting core elevator cylinder 98, blow core mold elevator cylinder 102, stretch-rod elevator cylinder 106 and eject cam elevator cylinder 110 retract the injection core mold 112, temperature adjusting core, blow core mold 100, stretch rod 104 and eject cam 108 from the rotary disc 66. Thus, the rotary disc 66 may be rotated. In such a situation, the electric motor 94 drives the rotary 16 disc 66 intermittently to move on to the subsequent step. An auxiliary clamping cylinder 128 is mounted on the traction plate 58 at a position opposite to the position below the stretch blow molding section 70. The auxiliary clamping cylinder 128 includes a piston (not shown), the tip of which is connected to the lower base 54. When the auxiliary clamping cylinder 128 is actuated with the neck mold clamping cylinder 120, the vertical movement of the upper base 56 may become smooth with improved balance on both the side of injection molding section 68 and the side of the stretch blow molding section 70. The machine bed 52 further includes synchronizing means 130 for synchronizing the operations of the neck mold clamping cylinder 120 and auxiliary clamping cylinder 128. The synchronizing means 130 comprises two racks 132, a rotating shaft 134 and two pinions 136. The racks 132 extend downwards from the lower base 54 at positions corresponding to the injection molding section 68 and stretch blow molding section 70. The rotating shaft 134 extends between the injection molding section 6 8 and the stretch blow molding section 70 and is vertically movable together with the traction plate 58. The pinions 136 are fixedly mounted on the rotating shaft 134 and respectively engage the two racks 132. In such an arrangement, the synchronizing means 130 synchronizes the movement between the neck mold clamping cylinder 120 and the auxiliary clamping cylinder 128 so that the traction plate 58 can move vertically while maintaining its horizontal level. Thus, the present invention provides a simple mechanism 17 which ensures synchronizing the operations of the clamping cylinders 120 and 128 so that the upper base 56 can move up and down smoothly while maintaining the upper base 56 horizontal. The injection molding section 68 also includes a stopper rod 140 for assisting to limit the lowermost position of the upper base 56. It is to be understood that the present invention is not limited to the aforementioned form, but may be carried out in any of various other forms without departing the scope of the invention. In the aforementioned embodiment, the apparatus comprises four molding sections, which are the injection molding section, the temperature adjusting section, the stretch blow molding section and the removing section, and the rotary means which is intermittently rotatable by 90 degrees to convey the products. However, the present invention may similarly be applied to any molding system including at least the injection molding section and stretch blow molding section. For example, the removing section may be omitted and the products may be removed at the stretch blowmolding section. Insuchacase, the injection molding section may be disposed directly opposite to the stretch blow molding section and the rotary means may be rotated by 180 degrees . The injection molding section, temperature adjusting section and stretch blow molding section may be disposed spaced apart from one another by 120 degrees and the rotary means may be rotated intermittently by 120 degrees . In such a case, the number of tie bars may be three. 18 Each of the clamping mechanisms is not limited to the piston- cylinder structure, but may take any of various other forms, for example, a toggle mechanism. 19 WE CLAIM: 1. An injection stretch blow molding apparatus comprising: a machine bed (52); an injection molding section (68) provided on the machine bed (52) for injection molding a preform; a stretch blow molding section (70) provided on the machine bed (52) for stretch blow molding the preform into a container; a rotary means (66) for intermittently conveying neck molds (90) to the respective injection molding section (68) and stretch blow molding section (70), the neck molds (90) being arranged thereon at positions corresponding to the respective injection molding section (68) and stretch blow molding section (70); a lower base (54) fixedly mounted on the machine bed (52); an upper base (56) provided above the lower base (54) to support the rotary means (66); characterized in that: a molding section is formed between the lower base (54) and the rotary disc (66); a traction plate (58) provided below the lower base (54) within the machine bed (52); a plurality of tie bars (62) slidably extending through the lower base (54) and connecting the upper base (56) to the traction plate (58); clamping means (120) provided within the machine bed (52) for vertically moving the traction plate (58); and an injection core mold clamping cylinder (116) is provided above the upper base (56) for vertically moving an injection core mold (112). -20- 2. The injection stretch blow molding apparatus as claimed in claim 1, wherein a cylinder fixing plate (60) is provided above the upper base (56), and an injection core mold clamping cylinder (116) is mounted on the cylinder fixing plate (60); and wherein the cylinder fixing plate (60), upper base (56) and traction plate (58) are fixedly secured to the tie bars (62) and vertically movable as a unit. 3. The injection stretch blow molding as claimed in claims 1 and 2, wherein the clamping means (120) is provided at a position below the injection molding section (68). 4. The injection stretch blow molding apparatus as claimed in claim 3, wherein the traction plate (58) is moved vertically by the clamping means (120) and an auxiliary claiming cylinder (128); and wherein the auxiliary clamping cylinder (128) is provided within the machine bed (52) at a position below the stretch blow molding section (70). 5. The injection stretch blow molding apparatus as claimed in claim 4, wherein within the machine bed (52) synchronizing means (130) is provided for synchronizing operations of the clamping means (120) and the auxiliary clamping cylinder (128). 6. The injection stretch blow molding apparatus as claimed in any one of the claims 1 to 5, wherein in the stretch blow molding section (70) a stopper (138) is provided for limiting a lower most position of the upper base (56) in said blow molding section (68) during its descent. -21- 7. An injection stretch blow molding apparatus comprising: a machine bed (52); an injection molding section (68) provided on the machine bed (52) for injection molding a preform; a stretch blow molding section (70) provided on the machine bed (52) for stretch blow molding the preform into a container; a rotary means (66) for intermittently conveying neck molds (90) to the respective injection molding section (68) and stretch blow molding section (70), the neck molds (90) being arranged thereon at positions corresponding to the respective injection molding section (68) and stretch blow molding section (70); a lower base (54) fixedly mounted on the machine bed (52); an upper base (56) provided above the lower base (54) to support the rotary means (66); characterized in that: the injection stretch blow molding apparatus further comprises: a molding section formed between the lower base (54) and the rotary disc (66); a traction plate (58) provided below the lower base (54) within the machine bed (52); a plurality of tie bars (62) slidably extending through the lower base (54) and connecting the upper base (56) to the traction plate (58); an injection core mold clamping cylinder (116) is provided above the upper base (56) for vertically moving an injection core mold (112); a clamping cylinder (120) provided below the injection molding section within the machine bed (52) for vertically moving the traction plate (58); -22- an auxiliary clamping cylinder (128) provided below the stretch blow molding section (70) within the machine bed (52) for vertically moving the traction plate; and synchronizing means (130) provided within the machine bed (52) for synchronizing operations of the clamping cylinder (120) and auxiliary clamping cylinder (128), comprising: two racks (132) extending downwards from the lower base (54) at respective positions corresponding to the injection and stretch blow molding sections (68, 70); a rotating shaft (134) provided extending between the injection molding section (68) and the stretch blow molding section (70) and vertically movable with the traction plate (58); and two pinions (136) fixedly mounted on the rotating shaft (134) and each of which is engaged with corresponding one of the two racks (132). An injection stretch blow molding apparatus 50 has an injection molding section 68, a stretch blow molding section 70 and a rotary disc 66 for intermittently conveying neck molds 90 to the respective injection molding section and stretch blow molding section. The apparatus further includes a lower base 54 fixedly mounted on a machine bed 52, an upper base 56 disposed above the lower base 54 for supporting the rotary means 66 and a traction plate 58 disposed below the lower base 54 within the machine bed 52. The upper base 56 and traction plate 58 are connected to each other through a plurality of tie bars 62 extending through the lower base 54. The machine bed 52 further includes a neck mold clamping cylinder 12 0 for moving the traction plate 58 in the vertical direction.

Documents:

00345-cal-2001 abstract.pdf

00345-cal-2001 assignment.pdf

00345-cal-2001 claims.pdf

00345-cal-2001 correspondence.pdf

00345-cal-2001 description(complete).pdf

00345-cal-2001 drawings.pdf

00345-cal-2001 form-1.pdf

00345-cal-2001 form-18.pdf

00345-cal-2001 form-2.pdf

00345-cal-2001 form-26.pdf

00345-cal-2001 form-3.pdf

00345-cal-2001 form-5.pdf

00345-cal-2001 letters patent.pdf

00345-cal-2001 priority document.pdf

00345-cal-2001 reply f.e.r.pdf

345-CAL-2001-FORM-27.pdf

345-cal-2001-granted-abstract.pdf

345-cal-2001-granted-claims.pdf

345-cal-2001-granted-description (complete).pdf

345-cal-2001-granted-drawings.pdf

345-cal-2001-granted-form 2.pdf

345-cal-2001-granted-specification.pdf

345-cal-2001-priority document.pdf

345-cal-2001-translated copy of priority document.pdf