Forming device of air spring blank and manufacturing process method of air spring

Abstract

The application discloses a forming device of an air spring blank and a manufacturing process method of an air spring. The forming device comprises a main body part having an inner cavity, an end mold arranged at the front end of the main body part, a core mold part penetrating through the inner cavity of the main body part, and the core mold part and the main body part defining a feeding cavity and an annular extrusion outlet. The main body part is provided with a feeding port. A feeding connector is installed at the feeding port, and a feeder is connected to the feeding connector to provide molten material with pressure to the feeding cavity through the feeding port. A core rod penetrates through the core mold part and is driven to move axially forward. A pressure buffer is arranged on the main body part and located at an axial position corresponding to the feeding port or in the feeding connector. The pressure buffer has a feeding hole and an elastic part capable of controlling the opening degree of the feeding hole through elastic deformation and resetting in response to the pressure change of the material provided by the feeder.

Description

Technical Field

[0001] This invention relates to the field of rubber and plastic material molding technology, and in particular to a molding device for an air spring blank and a manufacturing process for an air spring. Background Technology

[0002] Air springs (or air rubber springs) are typically installed on equipment prone to vibration to absorb vibrations and thus dampen the equipment. Because the elastic force (resistance) of an air spring is provided by pressurized gas encapsulated inside, it can provide a non-linear elastic force (resistance) that ordinary springs, such as helical columnar metal springs, cannot provide under pressure. Therefore, air springs have unique advantages in certain special vibration conditions and are difficult to replace with ordinary springs.

[0003] As is well known, the material used for the blank of an air spring is rubber. In the prior art, the blank of an air spring is usually manufactured by extrusion molding. A typical extrusion molding process is hard core extrusion. This hard core extrusion process usually uses an extrusion molding device with a core die component installed inside to extrude the rubber material into a tubular (or sleeve-shaped) air spring blank. Specifically, the extrusion molding device usually includes a main body component with an inner cavity, a core die component disposed in the inner cavity of the main body component and coaxially disposed with the main body component, and an end die disposed at the front end of the main body component. An axially extending supply cavity is defined between the main body component and the core die component, and an annular extrusion port is defined between the front end of the core die component and the end die. It is easy to understand that the supply cavity extends axially to the annular extrusion port. A radially extending feed port is opened on the side wall of the main body component. The feed port extends to the rear end of the supply cavity. A feed connector is installed at the feed port, and a feeder such as a screw extrusion device is connected to the feed connector. The feeder supplies molten material (rubber) into the feeding chamber through the feed port at a certain pressure, causing the material to move forward along the feeding chamber. The pressure provided by the feeder causes the material to be extruded from the annular extrusion port and formed into a tubular shape. On the other hand, the mandrel component has an axially penetrating cavity. A mandrel driven axially at a certain speed passes through the cavity, so that the tubular rubber extruded from the annular extrusion port covers the outer circumferential surface of the mandrel. After the tubular rubber covering the mandrel cools, it forms a blank for processing and manufacturing an air spring (if the air spring includes two rubber layers, i.e., two blanks, both blanks can be extruded by the above-mentioned extrusion molding device).

[0004] Understandably, the pressure provided by the feeder, as the power to extrude material from the annular extrusion nozzle, directly affects the uniformity of the blank thickness. For example, it affects the uniformity of the blank thickness in the axial direction, and also in the uniformity of the blank thickness in the circumferential direction. The uniformity of thickness directly affects the quality and lifespan of the manufactured air spring.

[0005] However, pressure fluctuations (pressure instability) frequently occur during extrusion molding, and the causes of pressure fluctuations can be:

[0006] 1. The material supplied by the upstream material source of the feeder is discontinuous or uneven, which leads to uneven pressure supplied by the feeder.

[0007] 2. The material flowing through the supply cavity between the core mold component and the main body component generates an unstable reaction force on the upstream feeder due to the inconsistent degree of melting, which in turn causes the feeder to exert fluctuating pressure on the material in the supply cavity.

[0008] 3. Fluctuations in the motor used to drive feeders such as screw extruders can also cause pressure fluctuations in the feeder.

[0009] The reason why pressure fluctuations affect the uniformity of billet thickness is:

[0010] 1. Pressure fluctuations cause uneven material extrusion from the annular extrusion nozzle, resulting in uneven thickness of the preform in the axial direction, i.e., different pipe sections have different thicknesses.

[0011] 2. As the material is radially fed into the supply chamber through the feed port, pressure fluctuations during the feeding process can easily cause the core mold component to vibrate radially. Even if the vibration is slight, it can cause the front end of the core mold component to be momentarily eccentric relative to the end mold, resulting in different thicknesses of the material flowing out from both sides of the annular extrusion port in the radial direction, thus causing uneven thickness of the blank in the circumferential direction. Summary of the Invention

[0012] In view of the above-mentioned technical problems existing in the prior art, the embodiments of the present invention provide a forming device for an air spring blank and a manufacturing process for an air spring.

[0013] To solve the above-mentioned technical problems, the technical solution adopted in the embodiments of the present invention is as follows:

[0014] An apparatus for forming an air spring blank, comprising:

[0015] The main component has an axially extending front end and a rear end, as well as an axially extending internal cavity that passes through the front end and the rear end.

[0016] An end mold is disposed at the front end of the main body component;

[0017] A core mold component passes through the inner cavity of the main body component. The rear end of the core mold component is fixed to the rear end of the main body component. The core mold component and the main body component define a supply cavity. The front end of the core mold component and the end mold define an annular extrusion port. The supply cavity extends through the annular extrusion port. The main body component has a radially extending inlet port near its rear end that extends through the supply cavity.

[0018] A feed connector is installed at the feed inlet, and a feeder is connected to the feed connector to supply pressurized molten material to the feed chamber through the feed inlet;

[0019] The mandrel passes through the mandrel component and is driven to move forward axially;

[0020] A pressure damper, mounted on the main body and located at the axial position corresponding to the feed port or in the feed connector, has a feed orifice that allows material to flow from the feed port to the feed chamber, and an elastic member that controls the opening degree of the feed orifice by elastic deformation and reset in response to pressure changes of the material supplied by the feeder. Thus, when the pressure of the supplied material increases, the elastic member reduces the opening degree of the feed orifice by elastic deformation, and when the pressure of the supplied material decreases, the elastic member increases the opening degree of the feed orifice by reset.

[0021] Preferably, the forming device for the air spring blank further includes an electric heating component and an airflow cooling mechanism;

[0022] The electric heating component includes an annular positioning component and a plurality of heating rods extending axially and arranged circumferentially on one side of the annular positioning component; circumferentially arranged insertion holes are provided from the rear end of the core mold component toward the front end, and the plurality of heating rods are correspondingly inserted into the plurality of insertion holes; the annular positioning component is fixed to the rear end of the core mold component.

[0023] The airflow cooling mechanism is installed at the front end of the end mold and sleeved on the mandrel. The airflow cooling mechanism includes an air-blowering shell with an annular air cavity. An air inlet for connecting to an air source is provided on the outer wall of the air-blowering shell. Multiple guide plates arranged circumferentially at intervals are provided on the inner side of the inner wall of the air-blowering shell. Multiple air outlets that penetrate to the annular air cavity are opened on the inner wall of the air-blowering shell between each pair of adjacent guide plates. The air outlets are inclined forward.

[0024] Preferably, the inner wall of the main component is provided with an annular groove at the axial position corresponding to the feed port, and annular stepped surfaces are formed on both sides of the annular groove;

[0025] The pressure buffer includes:

[0026] A ring-shaped component is disposed at the annular groove, and the two sides of the ring-shaped component are attached and fixed to the annular stepped surfaces on both sides of the annular groove; the supply holes include a plurality of holes, which are formed on the ring-shaped component and arranged in two groups in a circumferential manner.

[0027] A valve sleeve includes a ring portion, which is sleeved on and fixed to the ring sleeve component between the two sets of supply holes; the elastic component is an elastic rocker plate integrally formed on the side of the ring portion, and the elastic rocker plate includes multiple elastic rocker plates, which are divided into two groups and located on both sides of the ring portion, and each corresponds to one of the supply holes; wherein:

[0028] The elastic rocker and the supply hole are rectangular structures, and the width of the elastic rocker in the circumferential direction is smaller than the width of the supply hole in the circumferential direction.

[0029] Preferably, the pressure buffer is disposed in the inner hole of the feed connector; wherein:

[0030] The pressure buffer includes:

[0031] A circular plate component is horizontally placed and fixed in the inner hole of the feeding connector. The feeding holes include multiple holes, which are formed on the circular plate component and arranged circumferentially. Each feeding hole extends radially.

[0032] A valve ring includes a ring body, which is attached and fixed to the upper edge of the circular plate component. The elastic component is a strip-shaped component integrally formed on the radially inner side of the ring body. A plurality of strip-shaped components are arranged circumferentially and correspond one-to-one with a plurality of supply holes. The strip-shaped component is divided into a fixed part and a bent part in the circumferential direction. The fixed part is attached and fixed to one side of the supply hole in the circumferential direction. The bent part corresponds to the supply hole, and the width of the bent part in the circumferential direction is smaller than the width of the supply hole in the circumferential direction.

[0033] Preferably, the lower part of the pressure buffer is further equipped with a basket-shaped component, the basket-shaped component comprising an integrally formed outer cylinder and an inner cylinder, the outer cylinder and the inner cylinder forming a "W"-shaped cross-section, thereby defining an annular conical cavity with an open upper end and a closed lower end between the outer cylinder and the inner cylinder, and defining a conical cavity with a closed upper end and an open lower end within the inner cylinder, the outer cylinder being attached to the bottom edge of the circular plate component; wherein:

[0034] The inner cylinder wall is covered with flow holes. Material that enters the annular cone cavity through the supply hole on the circular plate component flows into the cone cavity through the flow holes.

[0035] Preferably, the core mold component includes a fixed sleeve, an adjusting sleeve, and a mold core; the rear end of the fixed sleeve is fixedly connected to the rear end of the main body component, the adjusting sleeve passes through the fixed sleeve and forms a threaded engagement with the fixed sleeve, and the mold core is fixed to the front end of the adjusting sleeve; wherein:

[0036] The front end of the mold core and the end mold define the annular extrusion port.

[0037] Preferably, the supply cavity includes a guide cavity and an extrusion cavity, the extrusion cavity being formed by the front end of the fixed sleeve, the mold core, the front end of the main body component, and the end mold;

[0038] An annular guide groove is provided at the axial position corresponding to the feed inlet of the fixed sleeve;

[0039] Multiple straight grooves extending axially and arranged circumferentially are formed on the outer peripheral surface of the fixed sleeve between the annular guide groove and the extrusion cavity, and the multiple straight grooves constitute the guide cavity.

[0040] Preferably, the fixing sleeve mates with the inner conical surface of the main body component.

[0041] Preferably, a positioning sleeve is fixed to the front end of the main body component, the end mold is fixed in the positioning sleeve, and an adjusting screw is radially inserted from the outside of the positioning sleeve. The head of the adjusting screw abuts against the outer peripheral surface of the end mold to adjust the axis of the end mold relative to the mold core.

[0042] Preferably, the rear end of the adjusting sleeve is provided with an adjusting plate, the adjusting plate has a pin hole, and the rear end face of the main body component corresponding to the adjusting plate has circumferentially arranged positioning holes, and the rotation of the adjusting plate is restricted by the pins passing through the pin holes and positioning holes.

[0043] This invention also discloses a manufacturing process for an air spring, including a molding process and a vulcanization process;

[0044] The molding process includes the following steps:

[0045] The molding process includes the following steps:

[0046] S11: Using the above-mentioned forming device, an inner preform covering the mandrel is extruded by the hard core method;

[0047] S12: Wrap ropes around the inner blank to form a skeleton layer, and wrap water cloth around the skeleton layer;

[0048] S13: The outer blank is extruded again using the forming device by the hard core method to cover the skeleton layer, thereby forming a capsule blank;

[0049] S14: Remove the preform from the mandrel;

[0050] S15: Cut the preform removed from the mandrel to the required length.

[0051] Preferably, the winding type of the rope in the skeleton layer is: type I, type X, or type Y.

[0052] Compared with the prior art, the beneficial effects of the air spring blank forming device and air spring manufacturing process provided by the present invention are:

[0053] The molding apparatus provided by the present invention can effectively reduce the impact of pressure fluctuations generated by the feeder during the supply of molten rubber on the axial and circumferential thickness of the blank by adding a pressure buffer upstream of the supply chamber. Attached Figure Description

[0054] Figure 1 This is a schematic diagram of the molding apparatus equipped with the pressure buffer provided in Example 1.

[0055] Figure 2 for Figure 1 A magnified view of part A (the opening of the supply hole is increased).

[0056] Figure 3 for Figure 1 A magnified view of part A (the opening of the supply hole is reduced).

[0057] Figure 4 This is a three-dimensional structural diagram of the pressure buffer provided in Example 1 with the supply orifice opening increased.

[0058] Figure 5 This is a three-dimensional structural diagram of the pressure buffer provided in Example 1 with the supply orifice opening reduced.

[0059] Figure 6 This is a schematic diagram of the molding apparatus equipped with the pressure buffer provided in Example 2.

[0060] Figure 7 for Figure 6 A magnified view of part B.

[0061] Figure 8 This is a three-dimensional structural diagram of the pressure buffer provided in Example 1 with the supply orifice opening increased.

[0062] Figure 9 The diagram shows a three-dimensional structure of the bottom of the basket-shaped component provided in Example 1.

[0063] Figure 10This is a three-dimensional structural diagram of the pressure buffer provided in Example 1 with the supply orifice opening reduced.

[0064] Figure 11 This is a three-dimensional structural diagram of the electric heating component in the molding apparatus provided by the present invention.

[0065] Figure 12 This is a three-dimensional structural diagram of the fixing sleeve in the molding device provided by the present invention.

[0066] Figure 13 This is a three-dimensional structural schematic diagram of the fixing sleeve in the molding device provided by the present invention from another perspective.

[0067] In the picture:

[0068] 10-Main body component; 11-Feed inlet; 12-Annular groove; 13-Insulation layer; 14-Heat insulation ring plate; 20-Core mold component; 21-Fixing sleeve; 211-Annular guide groove; 212-Straight groove; 213-Flange; 214-Positioning hole; 215-Wire hole; 216-Sink; 22-Adjusting sleeve; 23-Mold core; 24-Adjusting plate; 241-Pin hole; 242-Pin; 30-Feeding chamber; 31-Annular extrusion port; 32-Extrusion chamber; 33-Guide chamber; 40-End mold; 41-Positioning sleeve; 42-Pressure cap; 43-Adjusting screw; 50-Feeding connector; 70-Electric heating element; 71-Heating rod; 72-Annular positioning element; 80-Airflow cooling mechanism; 81-Blower shell; 811-Annular air chamber; 812-Outer wall; 813-Inner wall; 814-Air outlet; 82-Guide plate; 83-Air inlet; 90-Core rod; 100-Blank; 200-Feeder.

[0069] 61-Pressure buffer; 611-Ring assembly; 612-Supply port; 613-Ring; 614-Elastic rocker; 615-Valve sleeve;

[0070] 62-Pressure buffer; 621-Circular plate component; 622-Supply port; 623-Ring body; 624-Strip component; 6241-Bending part; 6242-Fixing part; 625-Valve ring;

[0071] 63-Basket-shaped component; 631-Outer cylinder; 632-Inner cylinder; 633-Annular conical cavity; 634-Conical cavity; 635-Flow hole. Detailed Implementation

[0072] To enable those skilled in the art to better understand the technical solution of the present invention, the present invention will be described in detail below with reference to the accompanying drawings and specific embodiments.

[0073] like Figure 1 and Figure 6As shown, an embodiment of the present invention discloses a molding apparatus for extruding rubber to form a blank 100 for an air spring. The molding apparatus includes: a main body component 10, an end mold 40, a core mold component 20, a feed connector 50, a mandrel 90, and pressure buffers 61 and 62.

[0074] The main body 10 has an axially penetrating inner cavity. The main body 10 has a radially extending inlet 11 that extends into the inner cavity at an axial position near its rear end. A feed connector 50 is attached to the inlet 11, and a feeder 200, such as a screw extrusion device, is connected to the feed connector 50.

[0075] A positioning sleeve 41 is detachably fixed to the front end of the main body component 10. The end mold 40 is disposed in the positioning sleeve 41. The positioning sleeve 41 is provided with six circumferentially distributed adjusting screws 43. The adjusting screws 43 all pass through the positioning sleeve 41 so that their heads abut against the outer circumferential surface of the end mold 40. In some preferred structures, the positioning sleeve 41 can be fixed to the front end of the main body component 10 by pressing the positioning sleeve 41 against the pressure cap 42.

[0076] The core mold component 20 is disposed in the inner cavity of the main body component 10. The core mold component 20 includes: a fixed sleeve 21, an adjusting sleeve 22, and a mold core 23. The rear end of the fixed sleeve 21 has a flange 213, which is fixed to the rear end face of the main body component 10 by fasteners, thereby fixing the fixed sleeve 21 to the main body component 10. The adjusting sleeve 22 passes through the inner hole of the fixed sleeve 21 and forms a threaded engagement with the fixed sleeve 21. The mold core 23 is fixed to the front end of the adjusting sleeve 22, and the front end of the mold core 23 and the front end of the end mold 40 define an annular extrusion port 31.

[0077] The fixed sleeve 21 and the mold core 23, together with the main body component 10 and the end mold 40, define an axially extending supply cavity 30. It can be understood that the annular extrusion port 31 is located at the front end of the supply cavity 30 and communicates with the supply cavity 30, while the feed port 11 on the main body component 10 communicates with the rear end of the supply cavity 30.

[0078] The mandrel 90 is axially inserted through the adjusting sleeve 22 and is driven by a linear drive mechanism (not shown) to move axially forward at a certain speed.

[0079] In use, the feeder 200 provides molten rubber at a certain pressure to the supply chamber 30 through the feed connector 50 and the inlet 11. The molten rubber entering the supply chamber 30 flows forward. Under the pressure provided by the feeder 200, the molten rubber is extruded from the annular extrusion port 31 and then covers the forward-moving mandrel 90 to form a tubular structure. After cooling, a blank 100 for making an air spring is formed on the mandrel 90.

[0080] In the above-mentioned molding apparatus:

[0081] The axis of the end mold 40 relative to the mold core 23 can be adjusted by turning the adjusting screw 43 at the positioning sleeve 41, so that a blank 100 with a uniform thickness in the circumferential direction can be extruded through the annular extrusion port 31 under a stable pressure.

[0082] The axial position of the die core 23 relative to the end die 40 can be adjusted by screwing the adjusting sleeve 22, thereby adjusting the opening of the annular extrusion orifice 31 and thus the thickness of the blank 100, which is beneficial for extruding blanks 100 of various thicknesses. In some preferred structures, an adjusting disc 24 is fitted at the rear end of the adjusting sleeve 22. The adjusting disc 24 is engaged with the adjusting sleeve 22 by a key structure, so that the adjusting sleeve 22 can rotate with the adjusting disc 24. A pin hole 241 is provided on the adjusting disc 24, and multiple circumferentially arranged positioning holes 214 are provided on the flange 213 of the fixed sleeve 21. Since the adjusting sleeve 22 is threadedly engaged with the fixed sleeve 21, the adjusting sleeve 22 can be rotated by a certain angle with the adjusting disc 24 by screwing the adjusting disc 24, thereby generating a certain axial displacement and adjusting the opening of the annular extrusion orifice 31. After adjusting the opening of the annular extrusion port 31, the pin 242 passes through the pin hole 241 and the corresponding positioning hole 214, thereby restricting the rotation of the adjusting plate 24 and keeping the annular extrusion port 31 at the adjusted opening.

[0083] In this invention, pressure buffers 61 and 62 are disposed upstream of the supply chamber 30, so that the molten rubber provided by the feeder 200 must first pass through pressure buffers 61 and 62 before entering the supply chamber 30. Specifically, pressure buffers 61 and 62 are mounted on the main body component 10 and located at the axial position corresponding to the inlet 11 or in the feed connector 50. Pressure buffers 61 and 62 have a supply hole that allows material to flow from the inlet 11 to the supply chamber 30, and elastic members that control the opening degree (aperture) of the supply hole by elastic deformation and reset in response to the pressure change of the material provided by the feeder 200. Thus, when the pressure of the supplied material increases, the elastic members reduce the opening degree of the supply hole by elastic deformation, and when the pressure of the supplied material decreases, the elastic members increase the opening degree of the supply hole by reset.

[0084] The functions of pressure buffers 61 and 62 are:

[0085] When the feeder 200 generates pressure fluctuations during the process of supplying molten rubber to the supply chamber 30, for example, the pressure fluctuation is characterized by a peak significantly higher than the rated supply pressure, or by a trough significantly lower than the rated supply pressure, or by a peak significantly higher than the rated supply pressure and a trough significantly lower than the rated supply pressure, or by a long fluctuation period, or by a short fluctuation period, the pressure buffers 61 and 62 buffer the pressure fluctuations by autonomously controlling the opening of the supply orifice, thereby largely preventing the pressure fluctuations from being transmitted to the supply chamber 30. Specifically, when the peak of the pressure fluctuation is significantly greater than the rated supply pressure, the elastic component responds to the excessive pressure generated by the pressure fluctuation by deforming towards the supply orifice, thereby reducing the opening of the supply orifice. This suppresses the portion exceeding the rated pressure more upstream of the pressure buffers 61 and 62. Furthermore, by consistently reducing the opening of the supply orifice, excessive flow of molten rubber into the supply chamber 30 is avoided. Conversely, when the trough of the pressure fluctuation is significantly lower than the rated supply pressure, the elastic deformation elastically resets away from the opening, increasing the opening of the supply orifice. This partially releases the pressure suppressed by the pressure buffers 61 and 62 into the supply chamber 30. Again, by consistently increasing the opening of the supply orifice, insufficient molten rubber into the supply chamber 30 due to excessively low pressure is avoided. Thus, even if pressure fluctuations occur when the feeder 200 supplies molten rubber, the flow rate of rubber extruded from the annular extrusion port 31 remains relatively stable, effectively reducing the impact of pressure fluctuations on the axial thickness of the preform 100.

[0086] In addition, the pressure buffers 61 and 62 can effectively mitigate the radial impact of pressure fluctuations on the fixed sleeve 21 by suppressing pressure fluctuations, thereby effectively reducing the radial vibration caused by pressure fluctuations on the fixed sleeve 21, and thus effectively reducing the impact of pressure fluctuations on the circumferential thickness of the blank 100.

[0087] The present invention provides two pressure buffer structures 61 and 62 through the following two embodiments. Example 1

[0088] like Figures 1 to 5 As shown, in this embodiment, the pressure buffer 61 is arranged on the inner wall of the main body component 10. Specifically, an annular groove 12 is provided on the inner wall of the main body component 10 at the axial position corresponding to the feed port 11, and annular stepped surfaces are formed on both sides of the annular groove 12.

[0089] The pressure buffer 61 in this embodiment includes a ring sleeve 611 and a valve sleeve 615. The ring sleeve 611 is disposed at the annular groove 12, and the two sides of the ring sleeve 611 are attached to the annular stepped surfaces on both sides of the annular groove 12 and fixed with screws. Multiple supply holes 612 are provided on the ring sleeve 611 and arranged in two circumferential groups. The valve sleeve 615 has a ring portion 613, which is fitted onto the ring sleeve 611 between the two groups of supply holes 612 and fixed to the ring sleeve 611 by spot welding or fasteners. The elastic component is an elastic rocker plate 614 integrally formed on the side of the ring portion 613. Multiple elastic rocker plates 614 are divided into two groups and located on both sides of the ring portion 613, thus corresponding one-to-one with the two groups of supply holes 612. The elastic rocker plate 614 is configured to be radially outwardly inclined. Figure 3 and Figure 5 As shown, when the elastic rocker 614 is subjected to excessive pressure (e.g., exceeding the rated pressure), it will elastically deform towards the supply hole 612, thereby reducing the opening of the supply hole 612. Figure 2 and Figure 4 As shown, when the elastic rocker 614 is subjected to too little pressure (e.g., below the rated pressure), it will elastically return to its original position away from the supply hole 612, thereby increasing the opening of the supply hole 612. Within the rated supply pressure range, the opening of the supply hole 612 is maintained between the above conditions.

[0090] In some more preferred configurations, both the elastic rocker 614 and the supply hole 612 are configured as rectangular structures, such that the circumferential width of the elastic rocker 614 is smaller than the circumferential width of the supply hole 612, thereby preventing the supply hole 612 from being completely closed by the elastic rocker 614.

[0091] For ease of installation, both the ring sleeve component 611 and the valve sleeve 615 are configured as two interlocking semicircular structures, which allows the semicircular structures to be easily inserted into the inner wall of the fixed sleeve 21.

[0092] The advantages of the pressure buffer 61 with the above structure are:

[0093] 1. The ring component 611 has a larger surface area, which allows for the arrangement of more supply holes 612 with a total cross-section, thereby allowing a larger flow rate of molten rubber, making it more suitable for applications requiring the extrusion of a thicker preform 100.

[0094] 2. The molten rubber supplied by the feeder 200 first enters the annular groove 12 through the feed port 11, and then passes through the feed holes 612 from various circumferential positions of the annular groove 12. Compared with the case of directly feeding into the supply chamber 30 radially through the feed port 11, this can alleviate the unbalanced radial impact of pressure fluctuations on the fixed sleeve 21 to a certain extent.

[0095] 3. The ring component 611 and the valve sleeve 615 can be integrally bent into shape by plate-shaped components. The supply hole 612 on the ring component 611 can be formed by stamping and cutting. The elastic rocker plate 614 on the valve sleeve 615 can be formed by cutting and bending. Therefore, the pressure buffer 61 is easier to manufacture. Example 2

[0096] like Figures 6 to 10 As shown, in this embodiment, the pressure buffer 62 is arranged in the inner hole of the feed connector 50.

[0097] In this embodiment, the pressure buffer 62 includes a circular plate component 621 and a valve ring 625. The circular plate component 621 is horizontally positioned and fixed in the inner hole of the feed connector 50. Multiple feed holes 622 are provided on the circular plate component 621 and arranged circumferentially, each extending radially. The valve ring 625 includes a ring body 623, which is attached to the upper edge of the circular plate component 621 by spot welding or fasteners. The elastic component is a strip-shaped component 624 integrally formed on the radially inner side of the valve ring 625. Multiple strip-shaped components 624 are arranged circumferentially and correspond one-to-one with the multiple feed holes 622. The strip-shaped component 624 is divided circumferentially into a fixing part 6242 and a bending part 6241. The fixing part 6242 is attached to one side of the feed hole 622 circumferentially by spot welding, and the bending part 6241 corresponds to the feed hole 622. Figure 10 As shown, when the bent portion 6241 is subjected to excessive pressure, it will deform towards the supply hole 622, thereby reducing the opening of the supply hole 622. Figure 7 and Figure 8 As shown, when the bent portion 6241 is subjected to too little pressure, it will elastically return to its original position away from the supply hole 622, thereby increasing the opening of the supply hole 622.

[0098] In some preferred configurations, the lower part of the pressure buffer 62 is further provided with a basket-shaped component 63, which includes an integrally formed outer cylinder 631 and an inner cylinder 632. The outer cylinder 631 and the inner cylinder 632 form a "W"-shaped structure, thereby defining an annular conical cavity 633 with an open upper end and a closed lower end between the outer cylinder 631 and the inner cylinder 632. A conical cavity 634 with a closed upper end and an open lower end is defined inside the inner cylinder 632. The outer cylinder 631 is attached to the bottom edge of the circular plate component 621. The inner cylinder 632 is covered with flow holes 635. The material that enters the annular conical cavity 633 through the supply hole 622 on the circular plate component 621 flows into the conical cavity 634 through the flow holes 635. Thus, the molten rubber after passing through the supply hole 622 of the pressure buffer 62 first enters the annular cone cavity 633, then enters the conical cavity 634 through the flow hole 635 of the inner cylinder 632, and then enters the supply cavity 30 through the port at the bottom of the conical cavity 634.

[0099] The advantages of the pressure buffer 62 and basket-shaped component 63 provided in this embodiment are:

[0100] 1. The pressure buffer 62 is more suitable for applications requiring the extrusion of a thinner blank 100.

[0101] 2. The basket-shaped component 63 allows molten rubber to enter the conical cavity 634 from the annular conical cavity 633 through the flow hole 635. During this process, the molten rubber is further mixed, thereby giving the molten rubber better material uniformity and temperature uniformity.

[0102] 3. The basket-shaped component 63 has a larger flow area that allows molten rubber to pass through, and therefore, the basket-shaped component 63 has less resistance to molten rubber.

[0103] 4. The pressure buffer 62 and the basket-shaped component 63 are also relatively easy to manufacture.

[0104] like Figures 11 to 13 and combined Figure 1As shown, in some preferred embodiments of the present invention, the molding apparatus further includes an electric heating component 70 and an airflow cooling mechanism 80, and the supply cavity 30 is constructed into two sections with different structures. Specifically, the supply cavity 30 includes a guide cavity 33 and an extrusion cavity 32. The extrusion cavity 32 is formed by the front end of the fixed sleeve 21, the mold core 23, the front end of the main body component 10, and the end mold 40, making the extrusion cavity 32 annular. An annular guide groove 211 is provided at the axial position corresponding to the feed port 11. A plurality of straight grooves 212 arranged circumferentially with axial extension are provided on the outer peripheral surface of the fixed sleeve 21 between the annular guide groove 211 and the extrusion cavity 32, and the plurality of straight grooves 212 constitute the guide cavity 33. Thus, the molten rubber entering the supply cavity 30 through the feed port 11 first fills the annular guide groove 211, and then enters the extrusion cavity 32 through the plurality of straight grooves 212 arranged circumferentially, and is subsequently extruded from the annular extrusion port 31. In some preferred configurations, the retaining sleeve 21 engages with the inner conical surface of the main body component 10.

[0105] The electric heating component 70 includes an annular positioning component 72 and multiple heating rods 71 ​​extending axially and arranged circumferentially on one side of the annular positioning component 72. A groove 216 is machined at the rear end of the fixing sleeve 21, and circumferentially arranged insertion holes are opened from the bottom of the groove 216 to the front end of the fixing sleeve 21. The multiple heating rods 71 ​​are inserted into the multiple insertion holes accordingly. The annular positioning component 72 is fixed to the bottom of the groove 216 by fasteners. A radially penetrating wire hole 215 is opened on the flange 213 of the fixing sleeve 21, and the wire passes through the wire hole 215 to connect to the electric heating component 70. In this way, as the molten rubber flows through the circumferentially arranged straight groove 212, the electric heating rods 71 ​​heat the molten rubber. This not only effectively prevents the molten rubber from solidifying when passing through the supply chamber 30, but more importantly, it makes the temperature of the molten rubber more uniform, so that a more uniformly thick blank 100 can be extruded from the annular extrusion port 31.

[0106] In addition, the molten rubber is supplied to the extrusion chamber 32 by using the straight groove 212, while the outer peripheral surface of the fixed sleeve 21 is still in a state of cooperation with the inner cavity wall of the main body component 10. This helps to suppress the uneven thickness of the blank 100 in the circumferential direction caused by the radial force imbalance.

[0107] An airflow cooling mechanism 80 is positioned in front of the end mold 40 and sleeved around the mandrel 90, specifically at the position where the rubber is extruded and just covers the mandrel 90. The airflow cooling mechanism 80 includes an air-bearing shell 81 with an annular air cavity 811. An air inlet 83 for connecting to an air source is provided on the outer wall 812 of the air-bearing shell 81. Multiple circumferentially spaced guide plates 82 are provided on the inner side of the inner wall 813 of the air-bearing shell 81. Multiple air outlets 814, penetrating to the annular air cavity 811, are opened on the inner wall 813 of the air-bearing shell 81 between each pair of adjacent guide plates 82. The air outlets 814 are inclined forward. An air source supplies pressurized gas into the annular air cavity 811 of the air-bearing shell 81 through the air inlet 83. The airflow in the annular air cavity 811 is then blown forward at an angle through the air outlets 814 onto the outer surface of the rubber just covering the mandrel 90, thereby facilitating the cooling of the rubber's outer surface.

[0108] The airflow cooling mechanism 80 is used in conjunction with the aforementioned electric heating component 70, and the airflow cooling mechanism 80 has the following advantages:

[0109] Because the surface temperature of the mandrel 90 is significantly lower than the temperature of the molten rubber (preform) extruded from the annular extrusion port 31, the inner surface of the rubber in contact with the mandrel 90 is cooled by the mandrel 90 and its temperature decreases. However, if the temperature difference between the outer surface and the inner surface of the rubber is too large, it will lead to inconsistent mechanical properties between the outer surface and the inner surface of the preform 100 after curing, which may in turn lead to inconsistent elastic deformation properties of the preform 100. The temperature difference can be effectively reduced by actively cooling the outer surface of the rubber through the airflow cooling mechanism 80, which is conducive to obtaining consistent mechanical properties between the outer surface and the inner surface of the formed preform 100.

[0110] In some preferred structures, an annular groove is formed on the outer peripheral surface of the main component 10. An insulation layer 13 is provided in the annular groove and the insulation layer 13 is sealed by a heat insulation ring plate 14. In this way, the heat dissipation of the molten rubber flowing through the straight groove 212 can be further reduced.

[0111] This invention also discloses a manufacturing process for an air spring. This process includes a step of creating a blank using the aforementioned molding device. The manufacturing process mainly comprises two steps: a molding step and a vulcanization step. The step of creating the blank using the molding device is one step within the molding process. This manufacturing process is used to produce an air spring comprising inner and outer blanks. For easier understanding, the blank located radially inner is commonly referred to as the inner rubber layer, and the blank located radially outer is commonly referred to as the outer rubber layer.

[0112] The molding process specifically includes:

[0113] S11: The inner rubber layer is extruded using a hard core extrusion process. Specifically, the inner rubber layer covering (encasing) the core rod 90 is extruded using the above-mentioned molding device (which is a device used in the hard core extrusion process).

[0114] S12: A reinforcing layer is formed by winding rope around the inner rubber layer, and then a water-repellent cloth is wound around the reinforcing layer to ensure a firm bond between the rope and the inner rubber layer. Specifically, a rope is evenly wound around the inner rubber layer using a conventional rope-splitting device, and then the water-repellent cloth is tightly wound around the reinforcing layer using a water-repellent cloth winding device. The rope winding type in the reinforcing layer is any one of type I, X, or Y, and the reinforcing layer is obtained by integral rope winding, which is beneficial for improving the mechanical performance or service life of the air spring.

[0115] S13: The outer rubber layer is extruded again using the hard core extrusion process to cover the skeleton layer. Specifically, the outer rubber layer covering the skeleton layer is extruded using the molding device described above to form a spring blank. It should be noted that if it is required to manufacture an air spring with multiple rubber layers, steps S12 and S13 can be repeated.

[0116] S14: Remove the preform formed by the above process from the mandrel 90.

[0117] S156: Cut the preform removed from the mandrel 90 to the required length.

[0118] The vulcanization process specifically includes: loading the blank into the vulcanization mold and inflating it to set its shape, and then vulcanizing it according to the vulcanization pressure, vulcanization temperature and vulcanization time specified in the existing technology. After vulcanization, the mold is opened and the blank is removed, thus producing an air spring.

[0119] Since the molding device provided by this invention extrudes the inner rubber layer (inner blank) and the outer rubber layer (outer blank) of the air spring, the thickness of the air spring is more uniform in both the axial and circumferential directions, which is beneficial to obtaining a more stable and certain elastic force of the air spring and to improving the service life of the air spring.

[0120] The above embodiments are merely exemplary embodiments of the present invention and are not intended to limit the present invention. The scope of protection of the present invention is defined by the claims. Those skilled in the art can make various modifications or equivalent substitutions to the present invention within its spirit and scope of protection, and such modifications or equivalent substitutions should also be considered to fall within the scope of protection of the present invention.

Claims

1. A forming device for an air spring blank, characterized in that, include: A main body component has an axially extending front end and a rear end, and an axially extending cavity through the front end and the rear end; an end mold is disposed at the front end of the main body component; a core mold component passes through the cavity of the main body component, the rear end of the core mold component is fixed to the rear end of the main body component, the core mold component and the main body component define a supply cavity, the front end of the core mold component and the end mold define an annular extrusion port, and the supply cavity extends to the annular extrusion port; a radially extending inlet port is provided on the main body component near its rear end, extending into the supply cavity; a feed connector is installed at the feed port, and a feeder is connected to the feed connector for supplying pressurized molten material to the supply cavity through the feed port; A mandrel, which passes through the mandrel component and is driven to move axially forward; a pressure buffer, which is mounted on the main body component and located at the axial position corresponding to the feed port or in the feed connector, the pressure buffer having a feed orifice that allows material to flow from the feed port to the feed chamber, and an elastic component that controls the opening degree of the feed orifice by elastic deformation and reset in response to pressure changes of the material supplied by the feeder. Thus, when the pressure of the supplied material increases, the elastic component reduces the opening degree of the feed orifice by elastic deformation, and when the pressure of the supplied material decreases, the elastic component increases the opening degree of the feed orifice by reset. The pressure buffer adopts one of the following two technical solutions: the main body component... The inner wall of the body component has an annular groove at an axial position corresponding to the feed inlet, and annular stepped surfaces are formed on both sides of the annular groove; the pressure buffer includes: a ring sleeve component, which is disposed at the annular groove, and the two sides of the ring sleeve component are attached and fixed to the annular stepped surfaces on both sides of the annular groove; the supply holes include multiple ones, which are formed on the ring sleeve component and arranged in two groups circumferentially; a valve sleeve includes a ring portion, which is sleeved on the ring sleeve component between the two groups of supply holes and fixed to the ring sleeve component; the elastic component is an elastic rocker plate integrally formed on the side of the ring portion, and the elastic rocker plate includes multiple ones, which are arranged in two groups and located on the... The two sides of the ring correspond one-to-one with the supply holes; wherein: the elastic rocker and the supply holes are rectangular structures, and the width of the elastic rocker in the circumferential direction is smaller than the width of the supply hole in the circumferential direction; or, when the pressure buffer is disposed in the inner hole of the feed connector, the pressure buffer includes: a circular plate component, which is horizontally placed and fixed in the inner hole of the feed connector, the supply holes include multiple ones, the multiple supply holes are opened on the circular plate component and arranged circumferentially, each of the supply holes extending radially; a valve ring, which includes a ring body, the ring body is attached and fixed to the upper edge of the circular plate component, the elastic component is a strip-shaped component integrally formed on the radially inner side of the ring body, multiple The strip-shaped components are arranged circumferentially and correspond one-to-one with the multiple supply holes; the strip-shaped components are divided into a fixed part and a bent part in the circumferential direction. The fixed part is attached to one side of the supply hole in the circumferential direction, the bent part corresponds to the supply hole, and the width of the bent part in the circumferential direction is smaller than the width of the supply hole in the circumferential direction; the lower part of the pressure buffer is also equipped with a basket-shaped component. The basket-shaped component includes an integrally formed outer cylinder and an inner cylinder. The outer cylinder and the inner cylinder form a "W" shaped structure in cross section, thereby defining an annular conical cavity with an open upper end and a closed lower end between the outer cylinder and the inner cylinder. A conical cavity with a closed upper end and an open lower end is defined inside the inner cylinder. The outer cylinder is attached to the bottom edge of the circular plate component.Wherein: the inner cylinder wall is covered with flow holes, and the material entering the annular cone cavity through the supply holes on the circular plate component flows into the cone cavity through the flow holes.

2. The forming apparatus for the air spring blank according to claim 1, characterized in that, The forming device for the air spring blank further includes an electric heating component and an airflow cooling mechanism; the electric heating component includes an annular positioning component and a plurality of heating rods extending axially and arranged circumferentially on one side of the annular positioning component; circumferentially arranged insertion holes are provided from the rear end of the core mold component toward the front end, and the plurality of heating rods are correspondingly inserted into the plurality of insertion holes, and the annular positioning component is fixed to the rear end of the core mold component; the airflow cooling mechanism is installed at the front end of the end mold and sleeved on the outside of the core rod, and the airflow cooling mechanism includes an air-blowering shell with an annular air cavity, an air inlet for connecting to an air source is provided on the outer wall of the air-blowering shell, a plurality of circumferentially spaced guide plates are provided on the inner side of the inner wall of the air-blowering shell between each two adjacent guide plates, and a plurality of air outlets penetrating to the annular air cavity are provided on the inner wall of the air-blowering shell, and the air outlets are inclined forward.

3. The forming apparatus for the air spring blank according to claim 1, characterized in that, The core mold component includes a fixed sleeve, an adjusting sleeve, and a mold core; the rear end of the fixed sleeve is fixedly connected to the rear end of the main body component, the adjusting sleeve passes through the fixed sleeve and forms a threaded engagement with the fixed sleeve, and the mold core is fixed to the front end of the adjusting sleeve; wherein: the front end of the mold core and the end mold define the annular extrusion port.

4. The forming apparatus for the air spring blank according to claim 3, characterized in that, The supply cavity includes a guide cavity and an extrusion cavity. The extrusion cavity is formed by the front end of the fixed sleeve, the mold core, the front end of the main body component, and the end mold. An annular guide groove is provided on the fixed sleeve at the axial position corresponding to the feed port. A plurality of axially extending and circumferentially arranged straight grooves are provided on the outer peripheral surface of the fixed sleeve between the annular guide groove and the extrusion cavity. The plurality of straight grooves constitute the guide cavity.

5. The forming apparatus for the air spring blank according to claim 3, characterized in that, The fixing sleeve mates with the inner conical surface of the main body component.

6. The forming apparatus for the air spring blank according to claim 3, characterized in that, A positioning sleeve is fixed to the front end of the main body component, and the end mold is fixed in the positioning sleeve. An adjusting screw is radially inserted from the outside of the positioning sleeve, and the head of the adjusting screw abuts against the outer peripheral surface of the end mold to adjust the axis of the end mold relative to the mold core.

7. A manufacturing process for an air spring, comprising a molding process and a vulcanization process; characterized in that, The molding process includes the following steps: S11: using the molding device as described in any one of claims 1 to 6, an inner blank is extruded using the hard core method to cover the mandrel; S12: a rope is wound around the inner blank to form a skeleton layer, and a water-repellent cloth is wound around the skeleton layer; S13: the molding device is used again to extrude an outer blank using the hard core method to cover the skeleton layer, thereby forming a capsule blank; S14: the capsule blank is removed from the mandrel; S15: the capsule blank removed from the mandrel is cut to the required length.

8. The manufacturing process of the air spring according to claim 7, characterized in that, The winding type of the rope in the skeleton layer is: I-type, X-type, or Y-type.

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