JP6134257B2 - Blow molding method and apparatus - Google Patents

Description

  In the present invention, a preform heated to an appropriate molding temperature is inserted into a space surrounded by a body or bottom molding die, and a blow molding gas is blown onto the inner surface of the preform from a hole of a stretch rod. The present invention relates to a blow molding method and apparatus for performing stretch blow molding.

Conventionally, bottles that have been stretch blow molded (hereinafter, stretch blow molding may be simply referred to as blow molding) are filled with contents that generate internal pressure, such as gas-containing beverages, in order to respond to diversification of the contents to be filled. For the use, the device that strengthens the strength of the bottom of the container at the time of blow molding, or for the filling of high-temperature contents, a device that increases the heat resistance by performing the secondary molding after the primary molding has been made . (Patent Documents 1 and 2)
Further, a device has been devised to ensure that the bottle formed during blow molding is released from the molding die. (Patent Document 3)
In recent years, as the demand for blow molded bottles has increased, further improvements to these blow molded bottles have not only strengthened the strength of the bottom of the bottle, but also ensured the release of the bottle from the mold for molding. There is a request for response.

JP 2000-343590 A (FIG. 1) JP 2006-264035 A (FIGS. 4 and 6) JP 2001-88202 A (FIGS. 1 and 2)

First, a conventional blow molding apparatus will be described with reference to FIGS.
FIG. 1 is a plan view of a blow molding line.
FIG. 2 is a view taken along the arrow II in FIG.
In FIG. 1, a blow molding line 50 is configured such that a preform P molded into a bottomed tubular body having a test tube shape is supplied into a clean room 51 surrounded by a wall 17 in the direction of arrow P <b> 1 from the upstream side. While being conveyed by the conveying device 61 in the direction indicated by the arrow, the heating device 54 is heated to an appropriate molding temperature in the conveying section suspended by the wheel 62 a and the wheel 62 b and passes through the wheel 64. After being transferred to the rotary blow molding device 56 and stretch blow molded into the blow molding container B, it is carried out to the next process in the direction of arrow B1 through the wheel 65 and the wheel 66.
The preform P or the blow-molded container B is held in a container gripper (not shown) of the equal pitch arrangement provided in the transfer device 61 and is transferred in the direction of the arrow shown.

  In the rotary blow molding device 56, blow molding dies 10 described later are equally arranged on the circumference, and a pump conveyed from the upstream side in synchronism with a container gripper (not shown) of the conveying device 61. Insertion and delivery of the reform P, and discharge and delivery of the blow molded container B to the downstream side are performed.

  As shown in FIGS. 1 and 2, the wheel 65 has a conveyance path in the direction of the arrow shown in FIG. 2 from a plurality of holes (not shown) toward the bottom Bb of the bottle B immediately after blow molding. A cooling air pipe 65P for blowing cooling air is disposed.

Next, a conventional blow molding die 10 will be described with reference to FIG.
FIG. 3 is a cross-sectional view taken along the line III-III of FIG. 1 and shows a blow mold.
In FIG. 3, a blow mold 10 (in FIG. 3, the symbol 10 is indicated by ()) is held by the container gripper 7 with its mouth Pm together with the stretch rod 9 and the airtight seal member 8. The preform P in which the lower part Pb of the part Pn is at an appropriate temperature for blow molding is opened and closed by a predetermined amount at the delivery position, and the body part molding die 5 and the bottom part molding die 46 (in FIG. 3). After the closing operation of the body forming die 5 and the bottom forming die 46 with the lower portion of the flange portion Pn being sandwiched, the cylinder 46 is inserted from above in the figure. The body-shaped stretch rod 9 is inserted from the center of the mouth portion Pm of the preform P toward the bottom of the inner surface of the preform P, and blow molding air is blown from the tip of the stretch rod 9. For molding The mold 5 and the bottom molding die 46 are molded into a blow molded container B along the shape of the cavity 5C and the cavity 46C (in FIG. 3, the symbol 46C is indicated by ()).
The container gripper 7 and the barrel forming mold 5 are hermetically sealed.

Next, the operation of the conventional blow molding apparatus 50 will be described.
The preform P heated to an appropriate molding temperature is blow-molded from the front end of the stretch rod 9 in the blow molding device 56 in the space formed by the body molding die 5 and the bottom molding die 46. After being formed into the bottle B along the shape of the cavity 5C and the cavity 46C by blowing air, the bottle B is transferred from the blow molding device 56 to the wheel 65 and conveyed by the wheel 65. Cooling air is blown to the bottom Bb of B from a plurality of holes (not shown) of the cooling air pipe 65P, and the bottom Bb is cooled and solidified.

  However, in the technique of the conventional blow molding device 56, the bottom Bb of the bottle B is cooled by the cooling air spraying from the cooling air piping 65P at the wheel 65 in the post-process of the blow molding device 56, so that the bottle B is molded. After a while, the bottom Bb is slowly cooled and there is a fear that the cooling and solidification performance is not sufficient.

Further, according to Patent Document 1, cooling air is blown from a cooling air blowing hole at a tip end portion of a stretching rod (stretch rod) to an inner surface of a bottle bottom portion which is held in a mold and blow-molded, and the bottom portion of the bottle. It is said that the strength of the bottom of the bottle will be strengthened by centrally cooling the bottle.
However, in the technique of Patent Document 1, only cooling air is blown to the bottom of the inner surface of the bottle, and since the bottom molding die 46 is not cooled, there is a possibility that it takes time to cool and solidify the bottom of the bottle. Therefore, there is a possibility that the strength at the bottom of the bottle is not sufficiently strengthened, and a technique for releasing the bottle bottom from the molding die is not mentioned.

According to Patent Document 2, the preform is expanded by primary blow molding to form an intermediate molded product. Further, after the intermediate molded product is heated, the intermediate molded product is taken out from the primary molding die and contracted and softened. The intermediate molded product in the state is secondarily blown in the secondary molding die and re-expanded into a bottle having excellent heat resistance. The posture is corrected by blowing compressed air to the center of the bottom.
However, in the technique of Patent Document 2, the compressed air blowing to the bottom of the intermediate molded product is aimed at correcting the posture of the intermediate molded product, and the compressed air is blown out aiming at one central portion of the bottom of the intermediate molded product. Therefore, when considered from the viewpoint of cooling and solidification of the bottom of the molded bottle, there is a risk that cooling and solidification of the entire outer surface of the bottle bottom is not performed in a well-balanced manner.

According to Patent Document 3, in the bottle stretch blow molding, the bottom of the bottle is reliably released from the mold by the protrusion of the protrusion member from the outside.
However, in the technique of Patent Document 3, the bottom of the bottle is released from the mold by the protrusion of the protrusion member having a complicated structure, which increases the cost of the protrusion member and causes the protrusion to reciprocate. There is a fear that the member is likely to be worn, and there is no mention of strength enhancement at the bottom of the bottle.

  In view of the above-described circumstances, the present invention is a blow molding improved and devised so as to double the strength of the bottom of the bottle and facilitate the release from the bottom molding die of the bottle after molding in the stretch blow molding of the bottle. It is an object to provide a method and apparatus.

The present invention solves the above problems by the following means.
(1) In the blow molding method of the first means of the present invention, a preform heated to an appropriate molding temperature is inserted into a space surrounded by a barrel or bottom molding die, and stretched inside the preform. In a blow molding method in which a blow molding gas is blown from a hole in a rod and stretch blow molded into a bottle, the outer surface of the bottom of the bottle during molding or at the end of molding from a plurality of appropriately distributed holes provided in the bottom molding die A cooling gas is sprayed on the outer surface of the bottom of the bottle through a plurality of exhaust holes appropriately distributed in the bottom molding die separately from the plurality of appropriately distributed holes. It is characterized by facilitating the exhaustion of the generated gas .

(2) The blow molding method of the second means of the present invention is the blow molding method of the first means, wherein the plurality of appropriately distributed holes and the plurality of exhaust holes are the bottom molding. It opens toward the space between the metal mold and the bottle bottom outer surface during molding or at the end of molding .
(3) The blow molding method of the third means of the present invention is characterized in that in the blow molding methods of the first and second means, the blowing of cold air and the exhaust are performed simultaneously.
(4) The blow molding method of the fourth means of the present invention is the blow molding method of the first to third means, wherein the plurality of appropriately distributed holes are opposed to a central portion of the outer surface of the bottle bottom. The plurality of exhaust holes include a plurality of holes that are equally distributed on the circumference.
(5) The blow molding method of the fifth means of the present invention is the blow molding method of the first to third means, wherein the plurality of appropriately distributed holes are equally distributed on the circumference. A plurality of holes are included, and the plurality of exhaust holes include a plurality of holes equally distributed on the circumference.

( 6 ) The blow molding method of the sixth means of the present invention is the blow molding method of the first to fifth means, wherein the blow molding gas is passed from the hole of the stretch rod to the bottom of the bottle inner surface at the end of blow molding. The switched cooling gas is sprayed to promote cooling and solidification of the bottom of the bottle.

( 7 ) The blow molding method of the seventh means of the present invention is the blow molding method of the first to sixth means, wherein a bactericidal agent is applied to the blow molding gas or cooling gas sprayed from the hole of the stretch rod. It is characterized in that the bottle inner surface can be sterilized during molding or at the end of molding.

( 8 ) The blow molding method according to the eighth means of the present invention is the blow molding method according to the first to seventh means, wherein the molding is further performed during or after molding from the hole provided in the side wall of the body molding die. A cooling gas is sprayed on the outer surface of the bottle body at the time to promote cooling of the molded bottle body.

( 9 ) The blow molding apparatus according to the ninth means of the present invention inserts a preform heated to an appropriate molding temperature into a body or bottom molding die and inserts it from above a stretch rod hole inserted from above the preform. In a blow molding device that blows blow molding gas onto the inner surface of a preform and stretch-blow-molds it into a bottle, the bottom molding die is quickly cooled and solidified at the bottom of the bottle during molding or at the end of molding, and from the bottom molding die. In order to facilitate mold release, a plurality of appropriately distributed holes for spraying a cooling gas are provided on the outer surface of the bottom of the bottle, and the bottom molding die is appropriately provided separately from the plurality of appropriately distributed holes. A plurality of exhaust holes distributed in the above are provided .

( 10 ) The blow molding apparatus of the eleventh means of the present invention is the blow molding apparatus of the ninth means, wherein the plurality of appropriately distributed holes and the plurality of exhaust holes are the bottom molding. It opens toward the space between the metal mold and the bottle bottom outer surface during molding or at the end of molding .
(11) The blow molding apparatus according to the eleventh means of the present invention is characterized in that in the blow molding apparatuses according to the ninth and tenth means, cold air blowing and exhaust can be performed simultaneously.
(12) The blow molding apparatus of the twelfth means of the present invention is the blow molding method of the ninth to eleventh means, wherein the plurality of appropriately distributed holes are opposed to a central portion of the outer surface of the bottom of the bottle. The plurality of exhaust holes include a plurality of holes that are equally distributed on the circumference.
(13) The blow molding method of the thirteenth means of the present invention is the blow molding method of the ninth to eleventh means, wherein the plurality of appropriately distributed holes are equally distributed on the circumference. A plurality of holes are included, and the plurality of exhaust holes include a plurality of holes equally distributed on the circumference.

( 14 ) The blow molding apparatus of the fourteenth means of the present invention is the blow molding apparatus of the ninth to thirteenth means, further cooling the bottom of the bottle at the end of the blow molding from the hole of the stretch rod to the inner surface of the bottle. A switching valve for switching from a blow molding gas to a cooling gas is provided in the piping circuit so as to blow a cooling gas that promotes solidification.

(15) 15th blow molding apparatus means of the present invention, sterilizing the first in nine blow molding apparatus of the fourteenth means, is et to the bottle inner surface at or during molding finished molding from the pores of the stretch rod The piping circuit is configured to blow a blow molding or cooling gas containing an agent.

( 16 ) The blow molding apparatus of the sixteenth means of the present invention is the blow molding apparatus of the ninth to fifteenth means, further comprising a hole for spraying a cooling gas on the side wall of the body molding die. It is characterized by that.

( 17 ) The blow molding apparatus of the seventeenth means of the present invention is the blow molding apparatus of the ninth to sixteenth means, wherein a cooling gas blowing hole or an exhaust hole is provided on the bottom of the bottle or the outer surface of the body. It is characterized by having a diameter of 1 to 2 mm.

  According to the first and sixth aspects of the present invention, a preform heated to an appropriate molding temperature is inserted into a space surrounded by a body or bottom molding die, and blow molding is performed on the inner surface of the preform from a hole of a stretch rod. In a blow molding method and apparatus for blowing a working gas to stretch-blow-mold a bottle, from a plurality of holes appropriately distributed in the bottom molding die to the outer surface of the bottom of the bottle during molding or at the end of molding By blowing the cooling gas, the bottle bottom can be quickly cooled and solidified during molding or at the end of molding to enhance the strength of the bottle bottom, and the bottle can be easily released from the bottom molding die. Has an effect.

  According to the second and seventh aspects of the present invention, in the blow molding method and apparatus according to the first and sixth aspects, the bottom outer surface is provided with a plurality of exhaust holes appropriately distributed in the bottom molding die. Because the cooling gas sprayed on the bottom is easily exhausted to the exhaust hole along the outer surface of the bottom, the amount of the cooling gas increases, so that the bottle bottom at the time of molding or at the end of molding is quickly cooled and solidified or the bottom molding gold This has the effect of facilitating release from the mold.

  According to the third and eighth aspects of the present invention, in the blow molding method and apparatus according to the first, second, sixth and seventh aspects, a cooling gas is blown from the hole of the stretch rod to the bottom of the inner surface of the bottle at the end of blow molding. By attaching, the cooling and solidification of the bottom of the bottle is promoted by cooling from the outer surface and the inner surface of the bottle bottom.

  The present invention according to claims 4 and 9 is the blow molding method and apparatus according to claims 1 to 3 and 6 to 8, wherein a disinfectant is applied to the blow molding gas or cooling gas sprayed from the hole of the stretch rod. By including, it has the effect that the inner surface of the molded bottle can be sterilized during the molding of the bottle or at the end of the molding.

  The present invention according to claims 5 and 10 is the blow molding method and apparatus according to claims 1 to 4 and 6 to 9, in addition to spraying a cooling gas from a hole provided in a bottom molding die, By providing a hole in the side wall of the body molding die to blow cooling gas to the bottle body during molding or at the end of molding, the cooling of the body as well as the bottom of the molding bottle is promoted. The body portion as well as the bottle bottom portion can be cooled and solidified at an early stage to enhance the strength, and the body portion together with the bottle bottom portion can be easily released from the mold.

  The present invention according to claim 11 is the blow molding apparatus according to any one of claims 6 to 10, wherein the cooling gas blowing hole or the exhaust hole has a diameter of 1 to 2 mm. Is sufficiently performed, and the traces of the holes remaining on the surface of the blow-molded bottle are remarkably small and unclear, which has an advantageous appearance.

It is a top view of a blow molding line. FIG. 2 is an II view of FIG. 1. It is a figure which shows a blow molding apparatus, and is the III-III figure of the cross section of FIG. It is a fragmentary front sectional view which shows the blow molding apparatus concerning the 1st Embodiment of this invention, and is a figure corresponded to the W section of FIG. FIG. 5 is a view showing only the symbol 6 in the VV diagram of FIG. 4. It is a fragmentary front sectional view which shows the blow molding apparatus concerning the 2nd and 3rd embodiment of this invention, and is a figure equivalent to FIG. It is a fragmentary front sectional view which shows the blow molding apparatus concerning the 4th Embodiment of this invention, and is a figure equivalent to FIG.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. Note that the present invention is not limited to the embodiments. In addition, constituent elements in the following embodiments include those that can be easily assumed by those skilled in the art or those that are substantially the same.

(First embodiment of the present invention)
A first embodiment of the present invention will be described with reference to FIG. 3, FIG. 4, and FIG.
FIG. 3 is a diversion of the conventional blow molding apparatus described above.
FIG. 4 is a partial front cross-sectional view showing the blow molding apparatus according to the first embodiment of the present invention, and corresponds to a portion W in FIG.
FIG. 5 is a view showing only the symbol 6 in the VV diagram of FIG.
In FIG. 4, the same structure as that in FIG. 3, which has been described with respect to the conventional blow molding apparatus, is given the same symbol, and redundant description is omitted.
In FIG. 4, the blow molding apparatus 1 according to the first embodiment of the present invention includes a cooling air (gas) in the direction of the arrow shown in the center of the outer surface of the bottom Bb of the bottle B on the bottom molding die 6. (A) 6a for spraying, a plurality of holes 6a1 branched from the middle of the hole (A) 6a, and a plurality of holes 6a2. As shown in FIG. 5, the plurality of holes 6a1 and the plurality of holes 6a2 are circumferentially distributed.
Further, an exhaust hole (B) 6b for cooling air blown from the hole (A) 6a, the plurality of holes 6a1, and the plurality of holes 6a2 to the bottom Bb of the bottle B during molding or at the end of molding, As shown in FIG. 5, a plurality of circularly distributed arrangements are provided.
The hole (A) 6a, the hole 6a1, the hole 6a2, and the hole (B) 6b have a diameter of 1 to 2 mm.

Next, the operation of the blow molding apparatus 1 according to the first embodiment of the present invention will be described with reference to FIGS.
Blow molding air is blown from the tip of the stretch rod 9 so that the bottom Bb of the bottle B during molding or at the end of molding is at the boundary with the bottom molding die 6 as shown by the arrow in the figure. A sufficient amount of cooling air is blown from the six holes (A) 6a, the plurality of holes 6a1, and the plurality of holes 6a2, and the bottom outer surface is stroked toward the plurality of exhaust holes (B) 6b. Thus, the air is exhausted as indicated by the arrows in the figure, so that the air volume of the cooling air is increased, cooling and solidification of the bottom Bb is promoted, and the strength of the bottom Bb is increased.
In addition, since the amount of cooling air blown from the hole (A) 6a, the plurality of holes 6a1, and the plurality of holes 6a2 is large, the bottom Bb can be easily released from the bottom molding die 6.
Since the cooling air hole (A) 6a, the hole 6a1, the hole 6a2, and the exhaust hole (B) 6b are configured with a diameter of 1 to 2 mm, the blow molded bottle B On the surface, the traces of the holes are extremely small and difficult to understand, which is convenient in appearance.

(Second Embodiment)
Next, a second embodiment of the present invention will be described with reference to FIGS.
FIG. 3 is a diversion of the conventional blow molding apparatus described above.
FIG. 6 is a partial front sectional view showing a blow molding apparatus according to the second embodiment of the present invention, and corresponds to FIG.
In FIG. 6, the same structure as that in FIG. 4 is denoted by the same symbol, and redundant description is omitted.
The blow molding apparatus 2 according to the second embodiment of the present invention (in FIG. 3, symbol 2 is indicated by ()), the bottom molding die 6 is the same as in the case of the first embodiment. Similarly, a preform P which is provided with cooling air blowing holes and exhaust holes and is at an appropriate temperature for blow molding is surrounded by the body molding die 5 and the bottom molding die 6. In this space, from the tip of the stretch rod 9 where blow molding air was blown at the time of molding, at the end of stretch blow molding, the blow air is cooled from the blow molding air by a switching valve (not shown) provided in the middle of the piping circuit. The cooling air CG is configured to be sprayed on the inner surface of the bottom Bb of the bottle B.

Next, the operation of the blow molding apparatus 2 according to the second embodiment of the present invention will be described.
During blow molding in which blow molding air is blown from the distal end portion of the stretch rod 9 or at the end of molding, the inner surface of the bottom Bb of the bottle B is switched from blow molding air to cooling air CG by a switching valve (not shown). Thus, the bottom Bb is cooled and solidified by blowing air for cooling on the outer surface of the bottom Bb from the hole (A) 6a and the hole 6a1 provided in the bottom molding die 6 and the hole 6a2. Since cooling and solidification is performed by blowing cooling air CG onto the inner surface of Bb, the cooling and solidification of the bottom Bb is rapidly promoted, and the strength of the bottom Bb is further increased.

(Third embodiment)
Next, a third embodiment of the present invention will be described with reference to FIGS.
FIG. 3 is a diversion of the conventional blow molding apparatus described above.
FIG. 6 is a partial front sectional view showing a blow molding apparatus according to the third embodiment of the present invention, and corresponds to FIG.
In FIG. 6, the blow molding apparatus 3 according to the third embodiment of the present invention displays the symbol 3 () and the symbol SG for blow molding or cooling air containing a disinfectant described later (). doing.
The blow molding apparatus 3 according to the third embodiment of the present invention (in FIG. 3, symbol 3 is indicated by ()) is the same as the case where the bottom molding die 6 is the first embodiment. Are provided with a hole for cooling air blowing and a hole for exhausting, and the stretch rod 9 is blow molding or cooling air SG containing a bactericidal agent in a preform P at a blow molding proper temperature. The piping circuit is configured to spray from the tip of the stretch rod 9.

Next, the operation of the blow molding apparatus 3 according to the third embodiment of the present invention will be described.
For the blow molding in which the preform P at the proper temperature for blow molding contains a bactericide from the tip of the stretch rod 9 in the space surrounded by the body molding die 5 and the bottom molding die 6 Since the air SG or the cooling air SG is sprayed, the inside of the bottle B is sterilized by the sterilizing agent.

(Fourth embodiment)
Next, a fourth embodiment of the present invention will be described with reference to FIGS.
FIG. 3 is a diversion of the conventional blow molding apparatus described above.
FIG. 7 is a partial front sectional view showing a blow molding apparatus according to the fourth embodiment of the present invention, and corresponds to FIG.
7, components having the same structure as those in FIG. 4 are denoted by the same symbols, and redundant description is omitted.
The blow molding apparatus 4 according to the fourth embodiment of the present invention (in FIG. 3, symbol 4 is indicated by ()), the bottom molding die 6 is the same as in the case of the first embodiment. Similarly, a cooling air blowing hole and an exhaust hole are provided, and the body forming mold 15 is provided on the side wall of the body side of the bottle B on the side wall. Is provided with a hole (C) 15c.

Next, the operation of the blow molding apparatus 4 according to the fourth embodiment of the present invention will be described.
Blow molding air is blown from the tip of the stretch rod 9 so that the bottom Bb of the bottle B during blow molding or at the end of molding is formed at the boundary between the bottom molding die 6 and the hole ( A) Cooling air is blown from 6a, hole 6a1, and hole 6a2, and a hole (C) 15c provided on the side wall of the body molding die 15 on the outer side surface of the bottle B during blow molding or at the end of molding. Cooling air can be sprayed from.
As a result, the bottom Bb of the bottle B during stretch blow molding or at the end of molding is cooled and solidified at an early stage, and the body is also cooled and solidified at an early stage, whereby the strength of both the bottom and the body of the bottle B is enhanced. At the same time, the mold release from the bottom or body mold is improved.

1, 2, 3, 4 Blow molding device 5 Body mold 6 Bottom mold 6a, 6a1, 6a2 Cooling air spray hole 6b Exhaust hole 9 Stretch rod 15 Body mold 15c Cooling Air blowing hole P Preform B Bottle Bb (Bottom) bottom CG Cooling air SG Blow molding or cooling air containing bactericidal agent

Claims (17)

A preform heated to an appropriate molding temperature is inserted into a space surrounded by a barrel or bottom molding die, and a blow molding gas is blown from a hole of a stretch rod inside the preform to stretch and blow the bottle. In the blow molding method for molding, cooling gas is blown to the outer surface of the bottom of the bottle during molding or at the end of molding from a plurality of appropriately distributed holes provided in the bottom molding die, and the plurality of appropriately distributed holes Apart from this, it is possible to facilitate the exhaustion of the gas blown to the outer surface of the bottom of the bottle through a plurality of exhaust holes provided appropriately distributed in the bottom molding die. Blow molding method. 2. The blow molding method according to claim 1, wherein the plurality of appropriately distributed holes and the plurality of exhaust holes include the bottom molding die and the bottle bottom outer surface during molding or at the end of molding. A blow molding method characterized by opening toward a space between the two. The blow molding method according to claim 1 or 2, wherein the blowing of cold air and the exhaust are performed simultaneously. In the blow molding method according to any one of claims 1 to 3,
  The plurality of appropriately distributed holes include holes provided so as to face a central portion of the outer surface of the bottle bottom,
  The plurality of exhaust holes include a plurality of holes that are equally distributed on the circumference.
A blow molding method. In the blow molding method according to any one of claims 1 to 3,
  The plurality of appropriately distributed holes include a plurality of holes equally distributed on the circumference,
  The plurality of exhaust holes include a plurality of holes that are equally distributed on the circumference.
A blow molding method. The blow molding method according to any one of claims 1 to 5 , further comprising blowing a cooling gas switched from a blow molding gas from a hole of the stretch rod to a bottom of the bottle inner surface at the end of blow molding, A blow molding method characterized by promoting cooling and solidification of a bottle bottom. The blow molding method according to any one of claims 1 to 6 , wherein the blow molding gas or cooling gas sprayed from the hole of the stretch rod includes a bactericide and is a bottle during molding or at the end of molding. A blow molding method characterized in that the inner surface can be sterilized. The blow molding method according to any one of claims 1 to 7 , wherein a cooling gas is further blown to a bottle body outer surface during molding or at the end of molding from a hole provided in a side wall of the body molding die. A blow molding method characterized in that cooling of the molded bottle body is also promoted. A preform heated to a suitable molding temperature is inserted into a body or bottom molding die, and a blow molding gas is blown onto the inner surface of the preform through a hole of a stretch rod inserted from above the preform, and stretch blow is applied to the bottle. In the blow molding apparatus for molding, the bottom molding die is provided with a plurality of appropriately distributed holes for spraying cooling gas on the outer surface of the bottom of the bottle during molding or at the end of molding , and the plurality of appropriately distributed A blow molding apparatus comprising a plurality of exhaust holes appropriately distributed in the bottom molding die separately from the holes . 10. The blow molding apparatus according to claim 9, wherein the plurality of appropriately distributed holes and the plurality of exhaust holes include the bottom molding die and the bottle bottom outer surface during molding or at the end of molding. A blow molding device having an opening toward a space between the two. The blow molding apparatus according to claim 9 or 10, wherein the blow molding apparatus can perform cold air blowing and exhaust simultaneously. In the blow molding device according to any one of claims 9 to 11,
  The plurality of appropriately distributed holes include holes provided so as to face a central portion of the outer surface of the bottle bottom,
  The plurality of exhaust holes include a plurality of holes that are equally distributed on the circumference.
A blow molding apparatus characterized by that. In the blow molding device according to any one of claims 9 to 11,
  The plurality of appropriately distributed holes include a plurality of holes equally distributed on the circumference,
  The plurality of exhaust holes include a plurality of holes that are equally distributed on the circumference.
A blow molding apparatus characterized by that. The blow molding apparatus according to any one of claims 9 to 13 , wherein a cooling gas that promotes cooling and solidification of the bottom of the bottle at the end of the blow molding is further sprayed from the hole of the stretch rod to the inner surface of the bottle. A blow molding apparatus characterized in that a switching valve for switching from a blow molding gas to a cooling gas is provided in a piping circuit. The blow molding apparatus according to any one of claims 9 to 14 , wherein a blow molding or cooling gas containing a bactericidal agent is further blown from the hole of the stretch rod to the inner surface of the bottle during molding or at the end of molding. A blow molding apparatus characterized by comprising a piping circuit. The blow molding apparatus according to any one of claims 9 to 15 , further comprising a hole for spraying a cooling gas on the outer surface of the bottle body during molding or at the end of molding on the side wall of the body molding die. A blow molding apparatus characterized by that. The blow molding apparatus according to any one of claims 9 to 16 , wherein the cooling gas blowing hole or the exhaust hole to the bottle bottom or body outer surface is configured to have a diameter of 1 to 2 mm. A blow molding device.

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