A sterilizable blow molding device and a sterilization method for the blow molding device.

Abstract

This invention relates to a sterilizable blow molding apparatus and a sterilization method for the blow molding apparatus. The sterilizable blow molding apparatus includes a cylinder, a piston shaft, a tension rod, an air nozzle, and an air source. The cylinder contains a sterilization channel, a mounting hole, and an air inlet. The mounting hole has a first annular groove and a second annular groove on its wall. The sterilization channel passes through the first annular groove, and the air inlet passes through the second annular groove. The piston shaft is vertically movable and passes through the mounting hole. A first sealing ring and a second sealing ring are fitted around the periphery of the piston shaft, forming a first gap between the piston shaft and the wall of the mounting hole. The tension rod is vertically movable and passes through the piston shaft, forming an air blowing channel between the tension rod and the piston shaft. The air blowing channel communicates with the first gap. The air nozzle is located at the bottom end of the piston shaft, and the air source communicates with the air inlet. The sterilizing gas can penetrate deep into all gaps inside the cylinder to thoroughly sterilize all channels and sealing rings that supply high-pressure air within the cylinder, thus improving sterilization quality.

Description

Technical Field

[0001] This invention relates to the field of blow molding machine technology, and more particularly to a sterilizable blow molding device and a sterilization method for the blow molding device. Background Technology

[0002] A blow molding machine is a device used to blow-molde preforms into bottle preforms. It mainly consists of a frame, a blow molding assembly mounted on the frame, and other supporting components. The blow molding assembly includes a lifting and lowering tension rod inserted into the preform, with a blowing channel around the tension rod for high-pressure gas flow. During the blow molding process, high-pressure gas is blown into the preform through the blowing channel, and the insertion of the tension rod promotes bottle forming. In related technologies, after the bottles are blow-molded, they are transferred to a sterilization station for appropriate sterilization treatment. To adapt to some special process adjustments or meet certain processing standards, the blow molding assembly needs to be sterilized to ensure the aseptic requirements of the preform during the blow molding process. However, existing blow molding assemblies do not have corresponding sterilization devices. Alternatively, ultraviolet sterilization devices are installed on the blow molding assembly, but this method easily creates sterilization dead zones inside the assembly, affecting the sterilization effect. Summary of the Invention

[0003] The purpose of this invention is to provide a sterilizable blow molding device and a sterilization method for the blow molding device, which can reduce sterilization dead zones and improve sterilization quality.

[0004] To achieve this objective, the present invention adopts the following technical solution: Firstly, a sterilizable blow molding device is provided, comprising: The cylinder body is provided with a sterilization channel, a mounting hole and an air inlet communicating with the outside. The mounting hole has a first annular groove and a second annular groove spaced apart along its axial direction on its wall. One end of the sterilization channel penetrates the bottom of the first annular groove and one end of the air inlet penetrates the bottom of the second annular groove. A piston shaft is provided, which can be raised and lowered through the mounting hole. A first sealing ring and a second sealing ring are sleeved on the periphery of the piston shaft. A first gap is formed between the piston shaft and the wall of the mounting hole. The first gap is located between the first sealing ring and the second sealing ring. A tension rod is provided, which can be raised and lowered through the piston shaft. An air blowing channel is formed between the tension rod and the piston shaft. A connecting hole is provided on the tension rod, and the air blowing channel is connected to the first gap through the connecting hole. An air nozzle is provided at the bottom end of the piston shaft and is connected to the air blowing channel; The gas source is connected to the air inlet. In the blowing state, both the first sealing ring and the second sealing ring abut against the wall of the mounting hole, and the first gap is connected only to the blowing channel. The gas source inputs high-pressure air into the air inlet. In the sterilization state, the first sealing ring and the second sealing ring face the first annular groove and the second annular groove respectively. The first gap is connected to the blowing channel and the sterilization channel, and the gas source inputs sterilizing gas into the air inlet.

[0005] As a preferred embodiment of the sterilizable blow molding device, the piston shaft is further fitted with a third sealing ring and a fourth sealing ring. The third sealing ring is located on the side of the first sealing ring away from the second sealing ring, and a second gap is formed between the third sealing ring and the first sealing ring. The fourth sealing ring is located on the side of the second sealing ring away from the first sealing ring, and a third gap is formed between the fourth sealing ring and the second sealing ring. In the sterilization state, both the second gap and the third gap are in communication with the sterilization channel.

[0006] As a preferred embodiment of a sterilizable blow molding device, the sterilization channel includes two inlet ends and one outlet end. The first annular groove is connected to one of the inlet ends of the sterilization channel, the third gap is connected to the other inlet end of the sterilization channel, and the outlet end of the sterilization channel is connected to the outside of the cylinder.

[0007] As a preferred embodiment of a sterilizable blow molding device, both the first sealing ring and the second sealing ring are inserted onto the piston shaft.

[0008] As a preferred embodiment of a sterilizable blow molding device, the multiple connecting holes are provided and are spaced apart along the circumferential direction of the piston shaft.

[0009] As a preferred embodiment of a sterilizable blow molding device, the sterilizing gas is hydrogen peroxide vapor.

[0010] As a preferred embodiment of the sterilizable blow molding device, it further includes a screw drive mechanism and a protective cover. The screw drive mechanism is connected to the top end of the tension rod and is used to drive the tension rod to move up and down. The protective cover is provided around the screw drive mechanism, and the top end of the tension rod is located inside the protective cover. The air source is in communication with the internal space of the protective cover.

[0011] As a preferred embodiment of a sterilizable blow molding device, the protective cover is provided with a sterile gas connector for connecting to the gas source. During blow molding, the gas source inputs sterile gas into the sterile gas connector, and the internal space of the protective cover is under positive pressure.

[0012] As a preferred embodiment of the sterilizable blow molding device, it further includes a cam drive mechanism and a lifting cylinder. The cam drive mechanism is connected to the piston shaft. In the blow molding state, the cam drive mechanism is used to drive the piston shaft to move up and down. The lifting cylinder is connected to the piston shaft. In the sterilization state, the lifting cylinder is used to drive the piston shaft to move up and down. The lifting stroke of the lifting cylinder is greater than the lifting stroke of the cam drive mechanism.

[0013] Secondly, a sterilization method for a blow molding apparatus is also provided, applicable to a sterilizable blow molding apparatus, comprising the following steps: Step S1: Move the relative position of the piston shaft and the cylinder body, and move the first sealing ring to the position directly opposite the first annular groove, and move the second sealing ring to the position directly opposite the second annular groove; Step S2: The gas source inputs sterilizing gas into the air inlet. Part of the sterilizing gas flows into the connecting hole and the blowing channel through the first gap, and part of the sterilizing gas flows into the sterilization channel through the first gap. Step S3: Collect the sterilizing gas from the outlet end of the sterilization channel and collect the sterilizing gas from the outlet end of the blowing channel.

[0014] The advantages of this invention compared to the prior art are: The present invention discloses a sterilizable blow molding apparatus and a sterilization method thereof. A sterilization channel is provided within the cylinder, and a first annular groove and a second annular groove are provided on the inner wall of the mounting hole. The sterilization channel communicates with the first annular groove. During blow molding, the piston shaft descends a certain distance, causing the first and second sealing rings to abut against the wall of the mounting hole. Under the sealing action of the first and second sealing rings, a first gap is isolated from other areas of the mounting hole. The first gap communicates only with the blowing channel through a connecting hole, allowing high-pressure gas to be smoothly blown onto the preform. During sterilization, the piston shaft rises a certain distance, causing the first sealing ring to move to the groove opening area of ​​the first annular groove, and the second sealing ring to move to the groove opening area of ​​the second annular groove. At this time, the first and second sealing rings separate from the wall of the mounting hole, allowing them to be exposed to the sterilizing gas. The sterilizing gas can penetrate into all gaps inside the cylinder, comprehensively sterilizing all channels and sealing rings within the cylinder that supply high-pressure air. This sterilizable blow molding device avoids sterilization dead zones during the sterilization process, which helps improve sterilization quality. Attached Figure Description

[0015] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments.

[0016] Figure 1 This is a schematic diagram of a sterilizable blow molding device according to an embodiment of the present invention.

[0017] Figure 2 This is a partial cross-sectional view (blowing state) of a sterilizable blow molding device according to an embodiment of the present invention.

[0018] Figure 3 This is a partial cross-sectional view (sterilization state) of a sterilizable blow molding device according to an embodiment of the present invention.

[0019] Figure 4 This is a schematic diagram of the protective cover according to an embodiment of the present invention.

[0020] In the picture: 1. Cylinder body; 101. First gap; 102. Second gap; 103. Third gap; 104. Sterilization channel; 1041. Channel outlet; 105. Air inlet; 106. First annular groove; 107. Second annular groove; 108. Limiting step; 2. Piston shaft; 201. Upper section; 202. Middle section; 203. Lower section; 204. Connecting hole; 205. Air blowing channel; 3. Tension rod; 4. Air blowing nozzle; 401. Bottle blowing hole; 5. First sealing ring; 6. 7. Second sealing ring; 8. Third sealing ring; 9. Fourth sealing ring; 10. Bracket; 11. Lifting cylinder; 11. Screw drive mechanism; 111. First guide rail; 112. Screw; 113. Slider; 114. Motor; 12. Protective cover; 121. Cover body; 122. Sterilization inlet; 123. Sterile gas connector; 124. Sterilization outlet; 13. Cam drive mechanism; 131. Follower wheel; 132. Second guide rail; 133. Slide block; 134. Connector. Detailed Implementation

[0021] The advantages and features of the present invention, as well as methods of implementing them, will become apparent from the following detailed description of the embodiments in conjunction with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but can be implemented in various different forms. These embodiments are provided merely to complete the disclosure of the invention and to enable those skilled in the art to fully understand the scope of the invention, which is defined only by the scope of the claims. The same reference numerals denote the same constituent elements throughout the specification.

[0022] The present invention will now be described in detail with reference to the accompanying drawings.

[0023] like Figure 2 and Figure 3As shown, the present invention provides a sterilizable blow molding device, comprising a cylinder 1, a piston shaft 2, a tension rod 3, an air nozzle 4, a first sealing ring 5, a second sealing ring 6, and an air source. The cylinder 1 is provided with a sterilization channel 104, a mounting hole, and an air inlet 105, all of which communicate with the outside of the cylinder 1. The mounting hole has a first annular groove 106 and a second annular groove 107 on its wall, spaced apart axially along the mounting hole. One end of the sterilization channel 104 penetrates the bottom of the first annular groove 106, allowing direct communication between the sterilization channel 104 and the first annular groove 106. One end of the air inlet 105 penetrates the bottom of the second annular groove 107, allowing direct communication between the air inlet 105 and the second annular groove 107. The piston shaft 2 passes through the mounting hole and is vertically movable, allowing it to move up and down relative to the cylinder 1. The first sealing ring 5 and the second sealing ring 6 are sleeved around the periphery of the piston shaft 2 at an axial distance. A gap exists between the piston shaft 2 and the wall of the mounting hole; the gap between the first sealing ring 5 and the second sealing ring 6 is the first gap 101. The tension rod 3 is long and passes through the piston shaft 2. The tension rod 3 is vertically adjustable to allow it to move up and down relative to the cylinder 1. A gap exists between the tension rod 3 and the inner wall of the piston shaft 2, and a blowing channel 205 is formed between the outer wall of the tension rod 3 and the inner wall of the piston shaft 2. A connecting hole 204 is provided on the tension rod 3, with both ends penetrating the outer and inner walls of the tension rod 3 respectively, so that the blowing channel 205 and the first gap 101 are connected through the connecting hole 204. The blowing nozzle 4 is used to directly contact and blow air onto the preform; the blowing nozzle 4 is located at the bottom end of the piston shaft 2 and communicates with the blowing channel 205. The air source is connected to the air inlet 105, and is used to store and supply high-pressure air and sterilizing gas to the air inlet 105. In the blow molding state, both the first sealing ring 5 and the second sealing ring 6 abut against the wall of the mounting hole, and the first gap 101 is only connected to the blowing channel 205. The air source inputs high-pressure air into the air inlet 105. The high-pressure air flows sequentially along the air inlet 105, the first gap 101, the connecting hole 204, and the blowing channel 205 to the blowing nozzle 4, and finally, the high-pressure air is blown out from the blowing nozzle 4 to blow-mold the preform. In the sterilization state, the piston shaft 2 is raised, with the first sealing ring 5 facing the first annular groove 106 and the second sealing ring 6 facing the second annular groove 107. The first gap 101 is connected to both the blowing channel 205 and the sterilization channel 104. The air source inputs sterilizing gas into the air inlet 105. The sterilizing gas flows through two paths. One path is that the sterilizing gas flows sequentially along the air inlet 105, the first gap 101, the connecting hole 204 and the blowing channel 205, and finally exits from the blowing nozzle 4 to sterilize the area it passes through.Another path is as follows: the sterilizing gas flows sequentially along the air inlet 105, the first gap 101, the first annular groove 106 and the sterilization channel 104, and finally exits from the outlet end of the sterilization channel 104 to sterilize the area it passes through.

[0024] It is understood that by setting a sterilization channel 104 inside the cylinder 1, and setting a first annular groove 106 and a second annular groove 107 on the inner wall of the mounting hole, the sterilization channel 104 is connected to the first annular groove 106. During the blowing state, the piston shaft 2 descends a certain distance, causing the first sealing ring 5 and the second sealing ring 6 to abut against the wall of the mounting hole. Under the sealing action of the first sealing ring 5 and the second sealing ring 6, the first gap 101 is isolated from other areas of the mounting hole. The first gap 101 is only connected to the blowing channel 205 through the connecting hole 204, so that high-pressure gas can be smoothly blown onto the preform. During the sterilization state, the piston shaft 2 rises a certain distance, causing the first sealing ring 5 to move to the groove opening area of ​​the first annular groove 106, and the second sealing ring 6 to move to the groove opening area of ​​the second annular groove 107. At this point, the first sealing ring 5 and the second sealing ring 6 separate from the wall of the mounting hole, allowing them to be exposed to the sterilizing gas. The sterilizing gas can penetrate all gaps inside the cylinder 1, thoroughly sterilizing all channels and sealing rings within the cylinder 1 that supply high-pressure air. This sterilizable blow molding device avoids sterilization dead zones during the sterilization process, thus improving sterilization quality.

[0025] Specifically, the axes of the piston shaft 2 and the tension rod 3 both extend vertically. Correspondingly, the mounting holes are vertically positioned, with their ends penetrating the top and bottom surfaces of the cylinder body 1, respectively. The first annular groove 106 and the second annular groove 107 both surround the piston shaft 2, with their openings facing the piston shaft 2. The first annular groove 106 is located above the second annular groove 107. The first annular groove 106 and the second annular groove 107 also serve to collect and distribute gas; sterilizing gas input from the air inlet 105 can flow through the second annular groove 107 to the area surrounding the piston shaft 2; sterilizing gas in the area surrounding the piston shaft 2 can flow through the first annular groove 106 into the sterilization channel 104. The piston shaft 2 is provided with multiple connecting holes 204, which are spaced apart along the circumference of the piston shaft 2. The connecting hole 204 is located near the second annular groove 107 so that high-pressure air or sterilizing gas can be distributed to each connecting hole 204 through the second annular groove 107 to improve gas flow efficiency.

[0026] A third sealing ring 7 and a fourth sealing ring 8 are also fitted around the periphery of the piston shaft 2. The third sealing ring 7 is located on the side of the first sealing ring 5 away from the second sealing ring 6, and is close to the top of the mounting hole. The third sealing ring 7 is inserted into the wall of the mounting hole and abuts against the piston shaft 2 to improve the overall sealing performance of the piston shaft 2. There is a gap between the piston shaft 2 and the wall of the mounting hole, and the gap between the third sealing ring 7 and the first sealing ring 5 is the second gap 102. The fourth sealing ring 8 is located on the side of the second sealing ring 6 away from the first sealing ring 5, and is close to the bottom of the mounting hole. The fourth sealing ring 8 is inserted into the wall of the mounting hole and abuts against the piston shaft 2 to improve the overall sealing performance of the piston shaft 2. There is a gap between the piston shaft 2 and the wall of the mounting hole, and the gap between the fourth sealing ring 8 and the second sealing ring 6 is the third gap 103. The first sealing ring 5 is inserted on the piston shaft 2, and the portion of the first sealing ring 5 outside the piston shaft 2 abuts against the wall of the mounting hole. The second sealing ring 6 is inserted into the piston shaft 2, and the portion of the second sealing ring 6 located outside the piston shaft 2 is used to abut against the wall of the mounting hole. When the piston shaft 2 moves up and down, the first sealing ring 5 and the second sealing ring 6 move synchronously with the piston shaft 2, so as to move the first sealing ring 5 and the second sealing ring 6 to the slot positions of the first annular groove 106 and the second annular groove 107, respectively. The sterilization channel 104 includes two inlet ends and one outlet end. One inlet end of the sterilization channel 104 communicates with the first annular groove 106, and the other inlet end communicates with the third gap 103. The outlet end of the sterilization channel 104 forms a channel outlet 1041, that is, the sterilization channel 104 communicates with the outside of the cylinder 1 through the channel outlet 1041. In the blowing state, the two inlet ends of the sterilization channel 104 communicate with the second gap 102 and the third gap 103, respectively. However, under the sealing effect of the first sealing ring 5 and the second sealing ring 6, high-pressure gas cannot enter the second gap 102 and the third gap 103. During sterilization, the first sealing ring 5 and the second sealing ring 6 lose their sealing function, allowing the first gap 101, the second gap 102, and the third gap 103 to communicate with the sterilization channel 104. The sterilization gas in the gap between the piston shaft 2 and the wall of the mounting hole is finally discharged through the channel outlet 1041.

[0027] Specifically, along the axial direction of the piston shaft 2, the piston shaft 2 includes an upper section 201, a middle section 202, and a lower section 203 connected sequentially from top to bottom. Parts of the upper section 201 and part of the middle section 202 are inserted into the mounting hole. The diameter of the middle section 202 is larger than the diameter of the upper section 201, and the diameter of the middle section 202 is larger than the diameter of the lower section 203. Correspondingly, a limiting step 108 is provided on the inner wall of the mounting hole. The limiting step 108 abuts against the end of the middle section 202 near the upper section 201 to limit the movement of the piston shaft 2. One end of the connecting hole 204 penetrates the end face of the middle section 202 near the upper section 201. The second annular groove 107 is located near the limiting step 108. Since there is a certain gap between the middle section 202 and the limiting step 108, by setting the second annular groove 107 close to the limiting step 108, the high-pressure air entering the second annular groove 107 can flow smoothly into the connecting hole 204 through the gap between the middle section 202 and the limiting step 108.

[0028] Specifically, the blowing nozzle 4 has a blowing hole 401 inside, which communicates with the blowing channel 205. High-pressure gas in the blowing channel 205 is blown into the preform through the blowing hole 401. A seal is also provided between the tension rod 3 and the piston shaft 2. The seal is located at the top of the piston shaft 2 and is used to seal the upper end of the blowing channel 205 so that high-pressure air or sterilizing gas can only be discharged from the lower end of the blowing channel 205.

[0029] Specifically, the sterilization gas is hydrogen peroxide vapor. To prevent the direct discharge of hydrogen peroxide vapor and its impact on the surrounding environment, a recovery pipeline is installed at the channel outlet 1041 of the sterilization channel 104, and a recovery pipeline is installed at the air nozzle 4, so as to recover the hydrogen peroxide vapor that has participated in the sterilization process.

[0030] Specifically, refer to Figure 1As shown, the sterilizable blow molding device also includes a support 9, a screw drive mechanism 11, a protective cover 12, a cam drive mechanism 13, and a lifting cylinder 10. The support 9 provides overall support, and the cylinder 1 is fixedly mounted on the support 9. The screw drive mechanism 11 is connected to the top end of the tension rod 3 and is used to drive the tension rod 3 to move up and down. The screw drive mechanism 11 includes a first guide rail 111, a screw 112, a slider 113, and a motor 114. The first guide rail 111 is fixedly mounted on the support 9, and its length extends vertically. The slider 113 is slidably connected to the first guide rail 111 and can slide along the length of the first guide rail 111. The screw 112 is rotatably mounted on the support 9, passes through the slider 113, and is threadedly connected to the slider 113. The motor 114 is fixedly mounted on the top of the support 9, and one end of the screw 112 is connected to the motor 114, which drives the screw 112 to rotate. The top end of the tension rod 3 is connected to the slider 113. The tension rod 3 is driven to move up and down by the sliding of the slider 113.

[0031] A protective cover 12 is installed around the screw drive mechanism 11, and the top end of the tension rod 3 is located inside the protective cover 12. The air source is connected to the internal space of the protective cover 12. In the sterilization state, the air source introduces sterilizing gas into the protective cover 12 to sterilize the screw drive mechanism 11 and the top area of ​​the tension rod 3, further improving the sterilization effect of the entire sterilizable blow molding device.

[0032] Specifically, refer to Figure 4 As shown, the protective cover 12 includes a cover body 121 and a sterilization inlet 122, a sterilization outlet 124, and a sterile gas connector 123 disposed on the cover body 121. The cover body 121 covers the periphery of the screw drive mechanism 11. The gas source is connected to the sterilization inlet 122 and the sterile gas connector 123, and the sterilization outlet 124 is connected to the recovery pipeline. In the sterilization state, the gas source inputs sterilizing gas into the protective cover 12 through the sterilization inlet 122, and the sterilizing gas after sterilization is discharged to the recovery pipeline through the sterilization outlet 124. The gas source is also used to store and output sterile gas to the protective cover 12. In the bottle blowing state, the sterilization inlet 122 and the sterilization outlet 124 are closed, and the gas source inputs sterile gas into the protective cover 12 through the sterile gas connector 123, making the internal space of the protective cover 12 a positive pressure state. Because there is an assembly gap at the connection between the protective cover 12 and other components, the protective cover 12 is kept under positive pressure by using sterile gas, which can prevent air or other media containing bacteria from entering the protective cover 12.

[0033] Specifically, continue to refer to Figure 1As shown, the cam drive mechanism 13 is connected to the piston shaft 2 and is used to drive the piston shaft 2 to move up and down. The cam drive mechanism 13 includes a cam, a follower wheel 131, a second guide rail 132, a slide block 133, and a connecting member 134. The second guide rail 132 is vertically mounted on the bracket 9, and the slide block 133 is slidably connected to the second guide rail 132 so that the slide block 133 can slide vertically on the second guide rail 132. One end of the connecting member 134 is connected to the slide block 133, and the follower wheel 131 is rotatably mounted on the end of the connecting member 134 away from the slide block 133. The cam abuts against the follower wheel 131, and relative movement occurs between the cam and the bracket 9, so that the follower wheel 131 rotates on the wheel surface of the cam. The wheel surface of the cam includes a flat section and a rising section, so that the follower wheel 131 moves up and down during the rotation along the cam, thereby causing the slide block 133 to move up and down on the second guide rail 132. The top end of piston shaft 2 is connected to slide 133 to enable cam drive mechanism 13 to drive piston shaft 2 to move up and down. Lifting cylinder 10 is fixedly mounted on bracket 9 and is selectively connected to piston shaft 2. In blow molding mode, lifting cylinder 10 is disconnected from piston shaft 2; in sterilization mode, lifting cylinder 10 is connected to piston shaft 2. Specifically, the output end of lifting cylinder 10 is connected to slide 133 to drive piston shaft 2 to move up and down via slide 133. In blow molding mode, the output end of lifting cylinder 10 is spaced apart from slide 133. Alternatively, if installation requirements are met, lifting cylinder 10 can be directly connected to piston shaft 2. Lifting cylinder 10 drives piston shaft 2 to move up and down, and the lifting stroke of lifting cylinder 10 is greater than the lifting stroke of cam drive mechanism 13. In blow molding mode, cam drive mechanism 13 drives piston shaft 2 to move up and down; in sterilization mode, lifting cylinder 10 drives piston shaft 2 to move up and down. In this embodiment, by setting a cam drive mechanism 13 to drive the piston shaft 2 to move up and down, the piston shaft 2 can periodically move up and down during bottle blowing to adapt to the air nozzle 4 moving closer to or further away from the preform. During this process, the first sealing ring 5 and the second sealing ring 6 always remain in contact with the wall of the mounting hole, and the first gap 101 communicates only with the air blowing channel 205. By setting a lifting cylinder 10 to drive the piston shaft 2 to move up and down, during sterilization, the lifting cylinder 10 can lift the piston shaft 2 and exceed the lifting stroke during bottle blowing, so that the first sealing ring 5 and the second sealing ring 6 can move to the groove opening positions of the first annular groove 106 and the second annular groove 107, respectively.

[0034] like Figures 1 to 3 As shown, the present invention also provides a sterilization method for a blow molding apparatus, applicable to a sterilizable blow molding apparatus. Specifically, it includes the following steps: Step S1: Move the relative position of the piston shaft 2 and the cylinder 1, and move the first sealing ring 5 to a position directly opposite the first annular groove 106, and the second sealing ring 6 to a position directly opposite the second annular groove 107. Specifically, during bottle blowing, the piston shaft 2 moves up and down to bring the blowing nozzle 4 closer to or away from the preform. During this process, the first sealing ring 5 always moves up and down below the first annular groove 106, and the second sealing ring 6 always moves up and down below the second annular groove 107. The first sealing ring 5 and the second sealing ring 6 can provide a seal between the piston shaft 2 and the cylinder 1. During sterilization, the piston shaft 2 is raised, the first sealing ring 5 moves to the opening of the first annular groove 106, and the second sealing ring 6 moves to the position of the second annular groove 107. The first sealing ring 5 and the second sealing ring 6 separate from the wall of the mounting hole, so that the first gap 101 communicates with the sterilization channel 104 and the blowing channel 205.

[0035] Step S2: Sterilizing gas is introduced into the air inlet 105 by the air source. Part of the sterilizing gas flows through the first gap 101 into the connecting hole 204 and the blowing channel 205, and part of the sterilizing gas flows through the first gap 101 into the sterilization channel 104. Specifically, in the sterilization state, the first sealing ring 5 is located at the opening of the first annular groove 106, and the first sealing ring 5 is separated from the wall of the mounting hole. At this time, the first gap 101 and the second gap 102 located on both sides of the first sealing ring 5 are connected to the sterilization channel 104, and the portion of the first sealing ring 5 extending out of the piston shaft 2 is also fully exposed. Part of the sterilizing gas entering the air inlet 105 flows into the first gap 101 and the second gap 102, and then enters the sterilization channel 104 through one of its inlet ends. Additionally, the second sealing ring 6 is located at the opening of the second annular groove 107, and the second sealing ring 6 is separated from the wall of the mounting hole. At this time, the first gap 101 and the third gap 103 located on both sides of the second sealing ring 6 are connected to the sterilization channel 104, and the part of the second sealing ring 6 extending out of the piston shaft 2 is also fully exposed. A portion of the sterilizing gas entering the air inlet 105 flows into the first gap 101 and the third gap 103, and then enters the sterilization channel 104 through the other inlet end. Since the sterilizing gas can flow into all gaps between the piston shaft 2 and the cylinder 1, it sterilizes the first sealing ring 5 and the second sealing ring 6 without any dead angles, thus ensuring the sterilization effect. Simultaneously, a portion of the sterilizing gas output from the air inlet 105 enters the connecting hole 204 and the blowing channel 205 through the first gap 101 to sterilize the gap between the piston shaft 2 and the tension rod 3 without any dead angles, thus ensuring the sterilization effect.

[0036] Step S3: Collect sterilizing gas from the outlet end of sterilization channel 104 and from the outlet end of blowing channel 205.

[0037] During sterilization, the recovery pipeline is connected to the outlet 1041 of the sterilization channel 104, and the recovery pipeline is installed on the air nozzle 4 so that the recovery pipeline is connected to the outlet end of the air blowing channel 205. The sterilization gas discharged from the sterilization channel 104 and the air blowing channel 205 is collected through the recovery pipeline to prevent the sterilization gas from being directly discharged into the external environment.

[0038] Specifically, the top end of the tension rod 3 is exposed outside the cylinder 1, and the top end of the tension rod 3 is used to connect with the lead screw drive mechanism 11 to drive the tension rod 3 to move up and down. Similarly, the top end of the piston shaft 2 is exposed outside the cylinder 1, and the top end of the piston shaft 2 is used to connect with the cam drive mechanism 13 to drive the piston shaft 2 to move up and down. Both the top ends of the piston shaft 2 and the tension rod 3 are housed within the protective cover 12. During sterilization, a sterilizing gas is introduced into the protective cover 12 to sterilize the top ends of the piston shaft 2 and the tension rod 3.

[0039] The beneficial effects of this embodiment are as follows: By setting a sterilization channel 104 inside the cylinder 1, and setting a first annular groove 106 and a second annular groove 107 on the inner wall of the mounting hole, the sterilization channel 104 is connected to the first annular groove 106. In the blowing state, the piston shaft 2 descends a certain distance, causing the first sealing ring 5 and the second sealing ring 6 to abut against the hole wall of the mounting hole. Under the sealing action of the first sealing ring 5 and the second sealing ring 6, the first gap 101 is isolated from other areas of the mounting hole. The first gap 101 is only connected to the blowing channel 205 through the connecting hole 204, so that the high-pressure gas can be smoothly blown to the preform. In the sterilization state, the piston shaft 2 rises a certain distance, causing the first sealing ring 5 to move to the groove opening area of ​​the first annular groove 106, and the second sealing ring 6 to move to the groove opening area of ​​the second annular groove 107. At this point, the first sealing ring 5 and the second sealing ring 6 separate from the wall of the mounting hole, allowing them to be exposed to the sterilizing gas. The sterilizing gas can penetrate all gaps inside the cylinder 1, thoroughly sterilizing all channels and sealing rings within the cylinder 1 that supply high-pressure air. This sterilizable blow molding device avoids sterilization dead zones during the sterilization process, thus improving sterilization quality.

[0040] Although embodiments of the invention have been described above with reference to the accompanying drawings, the invention is not limited to the above embodiments, but can be made in various forms, and those skilled in the art will understand that the invention can be implemented in other specific forms without changing the technical spirit or essential characteristics of the invention. Therefore, it should be understood that the above embodiments are exemplary in all respects and not restrictive.

Claims

1. A sterilizable blow molding device, characterized in that, include: The cylinder body is provided with a sterilization channel, a mounting hole and an air inlet communicating with the outside. The mounting hole has a first annular groove and a second annular groove spaced apart along its axial direction on its wall. One end of the sterilization channel penetrates the bottom of the first annular groove and one end of the air inlet penetrates the bottom of the second annular groove. A piston shaft is provided, which can be raised and lowered through the mounting hole. A first sealing ring and a second sealing ring are sleeved on the periphery of the piston shaft. A first gap is formed between the piston shaft and the wall of the mounting hole. The first gap is located between the first sealing ring and the second sealing ring. A tension rod is provided, which can be raised and lowered through the piston shaft. An air blowing channel is formed between the tension rod and the piston shaft. A connecting hole is provided on the tension rod, and the air blowing channel is connected to the first gap through the connecting hole. An air nozzle is provided at the bottom end of the piston shaft and is connected to the air blowing channel; The gas source is connected to the air inlet. In the blowing state, both the first sealing ring and the second sealing ring abut against the wall of the mounting hole, and the first gap is connected only to the blowing channel. The gas source inputs high-pressure air into the air inlet. In the sterilization state, the first sealing ring and the second sealing ring face the first annular groove and the second annular groove respectively. The first gap is connected to the blowing channel and the sterilization channel, and the gas source inputs sterilizing gas into the air inlet.

2. The sterilizable blow molding apparatus according to claim 1, characterized in that, The piston shaft is also fitted with a third sealing ring and a fourth sealing ring. The third sealing ring is located on the side of the first sealing ring away from the second sealing ring, and a second gap is formed between the third sealing ring and the first sealing ring. The fourth sealing ring is located on the side of the second sealing ring away from the first sealing ring, and a third gap is formed between the fourth sealing ring and the second sealing ring. In the sterilization state, both the second gap and the third gap are connected to the sterilization channel.

3. The sterilizable blow molding apparatus according to claim 2, characterized in that, The sterilization channel includes two inlet ends and one outlet end. The first annular groove is connected to one of the inlet ends of the sterilization channel, the third gap is connected to the other inlet end of the sterilization channel, and the outlet end of the sterilization channel is connected to the outside of the cylinder.

4. The sterilizable blow molding apparatus according to claim 1, characterized in that, Both the first sealing ring and the second sealing ring are inserted into the piston shaft.

5. The sterilizable blow molding apparatus according to claim 1, characterized in that, The connecting holes are configured as a plurality of holes, which are spaced apart along the circumferential direction of the piston shaft.

6. The sterilizable blow molding apparatus according to claim 1, characterized in that, The sterilizing gas is hydrogen peroxide vapor.

7. The sterilizable blow molding apparatus according to any one of claims 1 to 6, characterized in that, It also includes a lead screw drive mechanism and a protective cover. The lead screw drive mechanism is connected to the top end of the tension rod and is used to drive the tension rod to move up and down. The protective cover is placed around the lead screw drive mechanism and the top end of the tension rod is located inside the protective cover. The air source is connected to the internal space of the protective cover.

8. The sterilizable blow molding apparatus according to claim 7, characterized in that, The protective cover is provided with a sterile gas connector for connecting to the gas source. In the blowing state, the gas source inputs sterile gas into the sterile gas connector, and the internal space of the protective cover is under positive pressure.

9. The sterilizable blow molding apparatus according to any one of claims 1 to 6, characterized in that, It also includes a cam drive mechanism and a lifting cylinder. The cam drive mechanism is connected to the piston shaft. In the blow molding state, the cam drive mechanism is used to drive the piston shaft to move up and down. The lifting cylinder is connected to the piston shaft. In the sterilization state, the lifting cylinder is used to drive the piston shaft to move up and down. The lifting stroke of the lifting cylinder is greater than the lifting stroke of the cam drive mechanism.

10. A method for sterilizing a blow molding apparatus, characterized in that, The sterilizable blow molding apparatus according to any one of claims 1 to 9 comprises the following steps: Step S1: Move the relative position of the piston shaft and the cylinder body, and move the first sealing ring to the position directly opposite the first annular groove, and move the second sealing ring to the position directly opposite the second annular groove; Step S2: The gas source inputs sterilizing gas into the air inlet. Part of the sterilizing gas flows into the connecting hole and the blowing channel through the first gap, and part of the sterilizing gas flows into the sterilization channel through the first gap. Step S3: Collect the sterilizing gas from the outlet end of the sterilization channel and collect the sterilizing gas from the outlet end of the blowing channel.

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