Vacuum system for a plastic double-walled corrugated pipe forming machine

Abstract

The application discloses a vacuum system of a plastic double-wall corrugated pipe forming machine, and relates to the technical field of plastic double-wall corrugated pipe forming machines.The vacuum system comprises a vacuum guide rail, a module air passage and a sliding seat air passage, the module air passage is communicated with the sliding seat air passage, the vacuum guide rail is located in a forming channel area of a running platform and is floatingly connected with a mounting seat through a floating assembly, the upper vacuum guide rail and the lower vacuum guide rail of the vacuum guide rail are each provided with a plurality of guide rail air passages, when a plastic double-wall corrugated pipe is formed, the forming module participating in the forming moves to the forming channel area along with the sliding seat, the floating assembly located in the area is compressed by the sliding seat so that the side surface of the vacuum guide rail is tightly combined with the side surface of the sliding seat, meanwhile, the upper air passage of the sliding seat is communicated with the guide rail air passage of the upper vacuum guide rail, and the lower air passage of the sliding seat is communicated with the guide rail air passage of the lower vacuum guide rail.The vacuum system can meet the forming of the plastic corrugated pipe with super strong flaring, and can avoid pipe material forming defects caused by insufficient vacuum.

Description

Technical Field

[0001] This invention relates to the technical field of plastic double-wall corrugated pipe forming machines, and specifically to a vacuum system for a plastic double-wall corrugated pipe forming machine. Background Technology

[0002] In the application of double-wall corrugated pipes, the connection method between corrugated pipes is mainly a structure of flared and spigot joints with sealing rubber rings. However, this connection structure is prone to leakage. The main causes of leakage at the joint are aging of the rubber rings and deformation of the flared joint, with deformation being the primary factor. Therefore, it is necessary to optimize the flared joint structure to improve its rigidity and solve the deformation problem, providing customers with more reliable socket flared joints that fully meet standard requirements. This led to the concept of ultra-strong flared joints. Ultra-strong flared joints mean that the wall thickness of the flared section of the pipe must meet certain values, generally more than twice the thickness of the straight pipe's laminate. This significantly increases the rigidity of the flared pipe and effectively solves the flared joint deformation problem.

[0003] Producing plastic corrugated pipes with ultra-strong flaring places extremely high demands on the vacuum system of the plastic double-wall corrugated pipe forming machine. Existing vacuum systems cannot meet the requirements for producing ultra-strong flared plastic corrugated pipes, mainly due to the following drawbacks:

[0004] In the production process of commonly produced plastic corrugated pipes in China, vacuum can only enter the molding module through a single channel at the bottom of the sliding base. Due to mechanical structure limitations, the cross-sectional area of ​​the vacuum channel cannot be expanded indefinitely, and the vacuum flow rate in the vacuum channel is restricted, which can cause defects in the pipe molding process and reduce the molding efficiency. Furthermore, during prolonged production, impurities can enter the vacuum channel, causing the cross-sectional area of ​​the vacuum channel to shrink or the channel to become completely blocked. This can cause the molding module to lose vacuum in certain areas, failing to provide proper shaping for the pipe, leading to pipe collapse or even failure to form.

[0005] Furthermore, existing vacuuming solutions require connecting numerous vacuum hoses (also known as external ventilation pipes, external vacuum hoses, or external pipelines) from the vacuum pump unit to the molding machine. This necessitates leaving ample space around the production equipment to lay the vacuum hoses flat. The large number of pipes also occupies significant production space, severely impacting the production environment and posing serious safety hazards. Moreover, when the molding machine moves back and forth, a portion of the vacuum hoses needs to be towed by a cable chain. This not only requires high-powered equipment but also exposes the external pipelines to repeated bending and wear during movement, necessitating timely maintenance and replacement, significantly increasing costs. Summary of the Invention

[0006] In view of this, the technical problem to be solved by the present invention is to provide a vacuum system for a plastic double-wall corrugated pipe forming machine, which can not only meet the forming of plastic corrugated pipes with super-strong flaring and achieve good forming effect, but also avoid pipe forming defects caused by insufficient vacuum.

[0007] To solve the above-mentioned technical problems, the technical solution of the present invention is as follows:

[0008] A vacuum system for a plastic double-wall corrugated pipe forming machine is provided. The forming machine includes two operating platforms arranged opposite each other and operating synchronously. Each operating platform includes a mounting base with an annular track. A forming module is fixed on a sliding base and runs along the annular track via the sliding base. The vacuum system includes a vacuum guide rail, a module ventilation channel on the forming module, and a sliding base ventilation channel on the sliding base. The module ventilation channel is connected to the sliding base ventilation channel. The vacuum guide rail is located in the forming channel area of ​​the operating platform and is floatingly connected to the mounting base via a floating component. The vacuum guide rail runs along the opening and closing mold... The sliding seat is oriented and floating. The venting channel includes multiple upper venting channels and multiple lower venting channels. The vacuum guide rail includes an upper vacuum guide rail and a lower vacuum guide rail. The upper vacuum guide rail and the lower vacuum guide rail are each provided with multiple guide rail venting channels. When molding a plastic double-wall corrugated pipe, the molding module participating in the molding moves to the molding channel area with the sliding seat. The sliding seat located in the molding channel area compresses the floating component so that the side of the vacuum guide rail is tightly fitted to the side of the sliding seat. At the same time, the upper venting channel of the sliding seat is connected to the guide rail venting channel of the upper vacuum guide rail, and the lower venting channel of the sliding seat is connected to the guide rail venting channel of the lower vacuum guide rail.

[0009] Preferably, the molding module includes a molding module body and a module base plate, the molding module body and the module base plate are fixedly connected, the module ventilation channel includes a main vacuum channel assembly disposed on the molding module body and a module base plate vacuum cavity disposed on the module base plate, the main vacuum channel assembly includes a plurality of arc-shaped vacuum pipes and a transition vacuum channel located inside the molding module body, a plurality of vacuum slots opened at the molding cavity, and a plurality of side holes opened at the main side wall of the molding module, the side holes connecting the arc-shaped vacuum pipes and the vacuum slots, the transition vacuum channel connecting the arc-shaped vacuum pipes and the module base plate vacuum cavity respectively, and the module base plate vacuum cavity includes a base plate vacuum cavity connected to the upper ventilation channel of the sliding seat and a base plate lower vacuum cavity connected to the lower ventilation channel of the sliding seat.

[0010] Preferably, the floating component includes a bolt and a first elastic element, the mounting base is fixed with a plurality of spaced vacuum guide rail mounting bases, the upper vacuum guide rail and the lower vacuum guide rail are collectively referred to as vacuum guide rails, the vacuum guide rail mounting base is provided with a vacuum guide rail mounting groove, the first elastic element is provided between the vacuum guide rail mounting groove and the vacuum guide rail, and the bolt passes through the first elastic element to connect the vacuum guide rail mounting base and the vacuum guide rail.

[0011] Preferably, the vacuum guide rail is provided with a vacuum guide rail limiting assembly, which includes a fixing pin, an upper bearing and a lower bearing. The fixing pin is fixedly installed on the vacuum guide rail and extends out at both ends. The two extended ends are respectively fixedly installed with the upper bearing and the lower bearing. The circumferential surfaces of the upper bearing and the lower bearing are abutted against the side of one of the vacuum guide rail mounting seats.

[0012] Preferably, the vacuum guide rail includes at least two vacuum guide rail blocks, each of the vacuum guide rail blocks is provided with a guide rail vacuum cavity, adjacent vacuum guide rail blocks are fixedly connected by connectors, and the guide rail vacuum cavities of each vacuum guide rail block are not interconnected.

[0013] Preferably, the vacuum system includes multiple vacuum cylinders, which are fixed on the mounting base. Each vacuum cylinder is divided into several internal vacuum chamber areas, which correspond one-to-one with the guide rail vacuum chamber. The corresponding internal vacuum chamber areas and the guide rail vacuum chambers are connected by an external vent pipe, and a vacuum gauge is installed on the external vent pipe between them.

[0014] Preferably, the vacuum system includes an opening and closing frame, which is fixed below the mounting base. The opening and closing frame has a closed frame ventilation chamber, and the vacuum cylinder is connected to the frame ventilation chamber through an external ventilation pipe.

[0015] Preferably, the vacuum system includes a plurality of vacuum pumps, which are connected to the opening and closing frame via a piping assembly that can be selectively connected or disconnected.

[0016] The selectable connecting or disconnecting piping assembly includes a static piping assembly and a moving piping assembly. The static piping assembly is connected to the vacuum pump. The operating platform includes a base frame. The opening and closing frame can slide relative to the base frame. The moving piping assembly is fixedly connected to the opening and closing frame. When the moving piping assembly slides to the working position with the opening and closing frame, it is sealed and connected to the static piping assembly.

[0017] Preferably, the static pipe assembly includes a connector mounting base and a floating pipe connector that can slide relative to the connector mounting base, and an elastic floating structure is provided between the connector mounting base and the floating pipe connector. The dynamic pipe assembly is configured as a flexible hose connector.

[0018] Preferably, the static piping assembly includes a central vacuum tube connected to a floating pipe joint, a vacuum distributor joint, a plurality of first vacuum branch pipes, and a plurality of second vacuum branch pipes. The forming machine includes a sizing sleeve with a sizing vacuum chamber. The vacuum distributor joint is connected to the plurality of first vacuum branch pipes, the central vacuum tube, and the plurality of second vacuum branch pipes. The vacuum pump is connected to the vacuum distributor joint through the first vacuum branch pipes. The central vacuum tube is fixedly connected to the floating pipe joint. The plurality of second vacuum branch pipes are connected to the sizing vacuum chamber.

[0019] After adopting the above technical solution, the beneficial effects of the present invention are:

[0020] This invention discloses a vacuum system for a plastic double-wall corrugated pipe molding machine. The vacuum system includes a vacuum guide rail, a module air passage disposed on the molding module, and a sliding seat air passage disposed on the sliding seat. The module air passage is connected to the sliding seat air passage. The vacuum guide rail is located in the molding channel area of ​​the running platform and is floatingly connected to the mounting seat through a floating component. The vacuum guide rail floats along the mold opening and closing direction. The sliding seat air passage includes multiple upper sliding seat air passages and multiple lower sliding seat air passages. The vacuum guide rail includes an upper vacuum guide rail and a lower vacuum guide rail. The upper vacuum guide rail and the lower vacuum guide rail are respectively provided with multiple guide rail air passages. When molding the plastic double-wall corrugated pipe, the molding module participating in the molding moves to the molding channel area with the sliding seat. The sliding seat in the molding channel area compresses the floating component to make the side of the vacuum guide rail fit tightly against the side of the sliding seat. At the same time, the upper sliding seat air passage is connected to the guide rail air passage of the upper vacuum guide rail, and the lower sliding seat air passage is connected to the guide rail air passage of the lower vacuum guide rail. The upper and lower vacuum guide rails of the vacuum guide, along with multiple upper and lower air vents on the sliding seats, all work together to form the same molding module. Simply put, the molding module is connected to the vacuum guide rails and sliding seats through numerous vacuum channels. These vacuum channels are preferably distributed vertically, which not only increases the vacuum flow rate within the molding module, ensuring sufficient vacuum, but also prevents poor pipe molding due to blockage of some vacuum channels. This not only satisfies the molding requirements of plastic corrugated pipes with ultra-strong flaring, achieving excellent molding results, but also avoids pipe molding defects caused by insufficient vacuum.

[0021] The molding module includes a main body and a base plate. The module's ventilation system includes a main vacuum channel assembly on the main body and a base plate vacuum cavity on the base plate. The main vacuum channel assembly includes several arc-shaped vacuum pipes and transition vacuum channels inside the main body, multiple vacuum slots in the molding cavity, and multiple side holes on the main sidewall of the molding module. The side holes connect the arc-shaped vacuum pipes and vacuum slots. The transition vacuum channels connect the arc-shaped vacuum pipes and the base plate vacuum cavity. The base plate vacuum cavity includes an upper vacuum cavity connected to the upper ventilation channel of the sliding seat and a lower vacuum cavity connected to the lower ventilation channel of the sliding seat. This utilizes two sets of vacuum channels on the back of the molding module, ensuring a high vacuum throughput to the molding module, resulting in higher pipe molding efficiency and increased production speed. Simultaneously, it ensures sufficient vacuum to the molding module, resulting in full-bodied, aesthetically pleasing plastic corrugated pipes with ultra-widened ends. It can also be used for molding other large-diameter pipes requiring significant vacuum. The multiple vacuum slots in the molding module help improve the uniformity of vacuum suction, resulting in better tube molding. Even if some vacuum slots are blocked, it will not lead to insufficient vacuum flow, ensuring that the molded tube is full and aesthetically pleasing. This solves the problem of molding defects in tubes caused by blockage of the module's air passages or insufficient vacuum flow due to various reasons.

[0022] The vacuum system of the present invention has a closed frame with a ventilation chamber. The frame itself acts as a vacuum passage pipe, eliminating the need to install external pipelines (also known as external vacuum hoses or external pipes, etc.) into the frame of the molding machine. This not only eliminates the need for external pipelines but also the need for cable chains, simplifying installation and greatly reducing costs.

[0023] The vacuum pump and the opening / closing frame of the vacuum system of this invention are connected via a selectable connecting or disconnecting piping assembly. This assembly includes a static piping assembly and a moving piping assembly. The static piping assembly is connected to the vacuum pump. The operating platform includes a base frame, and the opening / closing frame can slide relative to the base frame. The moving piping assembly is fixedly connected to the opening / closing frame, and when it slides to the working position with the frame, it seals against the static piping assembly. This docking connection structure avoids the problem of a large number of external pipes being dragged along by a cable chain during the forward and backward movement of the molding machine, reducing power requirements and preventing repeated bending of the external pipes during movement, thus avoiding damage and reducing maintenance costs. The selectable connecting or disconnecting piping assembly also significantly reduces the number of external pipes, greatly minimizing the required production space and preventing serious safety hazards on-site.

[0024] In summary, the vacuum system of the plastic double-wall corrugated pipe forming machine of the present invention can provide sufficient vacuum, resulting in full-bodied pipes with high structural strength and good appearance. Furthermore, it avoids quality defects in the formed pipes caused by partial blockage of the vacuum channels in the forming module. It also significantly reduces the number of external pipelines, preventing serious potential safety hazards in on-site production. Attached Figure Description

[0025] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0026] Figure 1 This is a schematic diagram of the vacuum system of the plastic double-wall corrugated pipe forming machine of the present invention;

[0027] Figure 2 This is a top view schematic diagram of the vacuum system of the plastic double-wall corrugated pipe forming machine of the present invention;

[0028] Figure 3 This is a schematic diagram of the sliding seat, vacuum guide rail, and vacuum cylinder of the present invention mounted on the mounting base;

[0029] Figure 4 This is a schematic diagram of the upper vacuum guide rail structure;

[0030] Figure 5 yes Figure 4 A top view of the vacuum guide rail structure;

[0031] Figure 6 This is a schematic diagram of the molding module being mounted on the mounting base via a sliding seat;

[0032] Figure 7 yes Figure 6 A magnified view of a portion of the T-section;

[0033] Figure 8 A schematic diagram of the vacuum guide rail limiting assembly and its installation on the vacuum guide rail;

[0034] Figure 9 yes Figure 8 A top-view structural diagram;

[0035] Figure 10 yes Figure 6 Enlarged cross-sectional view at the FF point;

[0036] Figure 11 yes Figure 6 Enlarged cross-sectional view at point HH;

[0037] Figure 12 yes Figure 6 A schematic diagram of the forming module in the Z direction;

[0038] Figure 13This is a top view of the vacuum system installed on the second platform (a schematic diagram of the static and dynamic piping assemblies in the separated state).

[0039] Figure 14 This is a schematic diagram showing the connection state of the static pipe assembly and the dynamic pipe assembly.

[0040] Figure 15 yes Figure 1 Schematic diagram of the C-direction of the static piping assembly;

[0041] In the diagram: P1, First platform; P2, Second platform; 1, Mounting base; 11, Upper mounting plate; 12, Lower mounting plate; 2, Sliding seat; 21, Upper ventilation channel of the sliding seat; 22, Lower ventilation channel of the sliding seat; 3, Molding module; 30, Main body of the molding module; 301, Arc-shaped vacuum pipe; 302, Transition vacuum channel; 303, Vacuum groove; 304, Side hole; 31, Module ventilation channel; 32, Module base plate; 321, Vacuum cavity of the module base plate; 3211, Vacuum cavity on the base plate; 3212, Vacuum cavity below the base plate; 41, Upper vacuum guide rail; X, Inlet guide slope; 411, First vacuum guide rail block; 4111, Upper guide rail vacuum cavity one; 4112, Upper guide rail vacuum cavity two; 412. Second vacuum guide block; 4121. Upper guide rail vacuum chamber three; 413. Connector; 42. Lower vacuum guide rail; 43. Guide rail vent; 5. Floating assembly; 51. Bolt; 52. First elastic element; 6. Vacuum guide rail mounting base; 61. Vacuum guide rail mounting groove; 7. Vacuum guide rail limiting assembly; 71. Fixing pin; 72. Upper bearing; 73. Lower bearing; 8. Vacuum cylinder; 81. First vacuum cylinder; 82. Second vacuum cylinder; 9. Opening and closing frame; 10. Vacuum pump; 100. Base frame Frame; J, Static piping assembly; V, Dynamic piping assembly; 101, Connector mounting base; 102, Floating pipe connector; 1021, First limiting baffle; 1022, Second limiting baffle; 1023, Limiting nut; 103, Flexible hose connector; 104, Connecting guide rod; 105, Second elastic element; 107, Vacuum concentrator tube; 108, Vacuum distributor connector; 1091, First vacuum distributor; 1092, Second vacuum distributor; D, Sizing sleeve; K, Mold opening / closing direction; S, Production direction. Detailed Implementation

[0042] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0043] In the description of this invention, it should be noted that the terms "front", "rear", "center", "upper", "lower", "left", "right", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting this invention.

[0044] Furthermore, although terms such as first, second, third, etc., may be used in this document to describe multiple elements, components, regions, layers, and / or segments, these elements, components, regions, layers, and / or segments should not be limited by these terms. These terms may be used only to distinguish one element, component, region, layer, or segment from another. Unless the context clearly indicates otherwise, terms such as "first," "second," and other numerical terms used in this document do not imply order or sequence. Therefore, the first element, component, region, layer, or segment discussed below may be referred to as the second element, component, region, layer, or segment without departing from the teachings of the exemplary embodiments.

[0045] like Figure 1 and Figure 2 As shown, the vacuum system of the plastic double-wall corrugated pipe forming machine is used in the forming machine. The forming machine includes two running platforms that are arranged opposite each other and run synchronously. The two running platforms are a first platform P1 and a second platform P2, which run synchronously. Each running platform includes a mounting base 1, on which a ring track is provided. The forming module 3 is fixed on a sliding base 2 and runs along the ring track through the sliding base 2. When the forming module 3 runs to the forming area of ​​the two platforms, the two forming modules 3 in opposite positions close together to form the forming mold of the outer tube.

[0046] The vacuum system includes a vacuum guide rail, a module ventilation channel 31 disposed on the molding module 3, and a sliding seat ventilation channel disposed on the sliding seat 2. The module ventilation channel 31 is connected to the sliding seat ventilation channel. The vacuum guide rail is located in the molding channel area of ​​the running platform and is floatingly connected to the mounting seat 1 through the floating component 5. The vacuum guide rail floats in the mold opening and closing direction K. The sliding seat ventilation channel includes multiple upper sliding seat ventilation channels 21 and multiple lower sliding seat ventilation channels 22.

[0047] like Figures 3 to 6As shown, the vacuum guide rail includes an upper vacuum guide rail 41 and a lower vacuum guide rail 42. Both the upper and lower vacuum guide rails 41 and 42 are provided with multiple guide rail ventilation channels 43. When molding the plastic double-wall corrugated pipe, the molding module 3, which participates in the molding, moves to the molding channel area along with the sliding seat 2. The sliding seat 2, located in the molding channel area, compresses the floating assembly 5 to make the side of the vacuum guide rail fit tightly against the side of the sliding seat 2. Simultaneously, the upper ventilation channel 21 of the sliding seat is connected to the guide rail ventilation channel 43 of the upper vacuum guide rail 41, and the lower ventilation channel 22 of the sliding seat is connected to the guide rail ventilation channel 43 of the lower vacuum guide rail 42. In simple terms, when the molding module 3 installed on the sliding seat 2 moves to the molding channel, it uses vacuum suction to make the pipe material blank fit tightly against the inner cavity of the module for molding (forming the outer wall of the double-wall corrugated pipe).

[0048] The upper vacuum guide rail 41 and the lower vacuum guide rail 42 work together on the same forming module, which not only helps to increase the vacuum flow rate in the forming module, but also avoids poor tube forming due to blockage of some vacuum channels.

[0049] like Figure 6 , Figure 10 , Figure 11 and Figure 12 As shown, the molding module 3 includes a molding module body 30 and a module base plate 32. The molding module body 30 and the module base plate 32 are fixedly connected. The module ventilation channel 31 includes a main vacuum channel assembly disposed on the molding module body 30 and a module base plate vacuum cavity 321 disposed on the module base plate 32. The main vacuum channel assembly includes several arc-shaped vacuum pipes 301 and a transition vacuum channel 302 located inside the molding module body 30, several vacuum slots 303 opened at the molding cavity, and several side holes 304 opened at the main side wall of the molding module 3. The side holes 304 connect the arc-shaped vacuum pipes 301 and the vacuum slots 303. The transition vacuum channel 302 connects the arc-shaped vacuum pipes 301 and the module base plate vacuum cavity 321 respectively. The module base plate vacuum cavity 321 includes a base plate vacuum cavity 3211 connected to the upper ventilation channel 21 of the sliding seat and a base plate lower vacuum cavity 3212 connected to the lower ventilation channel 22 of the sliding seat. In other words, two sets of vacuum channels, one upper and one lower, are used on the back of molding module 3, resulting in higher tube forming efficiency and improved tube production speed. Simultaneously, it ensures sufficient vacuum to reach molding module 3, resulting in full-bodied, aesthetically pleasing plastic corrugated pipes with ultra-widened ends. This solves the problem of incomplete or unattractive formed pipes caused by blockage of the module's air intake seams or insufficient vacuum flow due to various reasons.

[0050] The multiple vacuum grooves 303 in the forming module 3 help to improve the uniformity of vacuum suction, resulting in good pipe forming effect. Even if a small part of the vacuum grooves 303 are blocked, it will not lead to insufficient vacuum flow, ensuring that the formed pipe is full and has a beautiful appearance.

[0051] When producing large-diameter pipes, due to the thick outer layer, or when producing plastic corrugated pipes with ultra-strong flares where the flare thickness is more than twice the thickness of the straight pipe lamination, the forming mold requires a large vacuum flow rate for shaping. The vacuum system of the plastic double-wall corrugated pipe forming machine of this invention can provide sufficient vacuum, resulting in full-bodied pipes with high structural strength and good appearance. Furthermore, it can avoid quality defects in the formed pipes caused by blockage of some vacuum channels in the forming module.

[0052] In some embodiments, such as Figures 7 to 9 As shown, the floating component 5 includes a bolt 51 and a first elastic element 52. The mounting base 1 is fixed with multiple spaced vacuum guide rail mounting seats 6. Each vacuum guide rail mounting seat 6 has a vacuum guide rail mounting groove 61. The first elastic element 52 is provided between the vacuum guide rail mounting groove 61 and the vacuum guide rail. The bolt 51 passes through the first elastic element 52 to connect the vacuum guide rail mounting seat 6 and the vacuum guide rail. Preferably, the first elastic element 52 is preferably a spring.

[0053] The installation structure of the vacuum guide rail 41 and the vacuum guide rail mounting groove 61 will be described in detail using the above example. An elastic element mounting groove for mounting the first elastic element 52 is provided between the vacuum guide rail mounting groove 61 and the upper vacuum guide rail 41. That is, the elastic element mounting groove can be provided only on the vacuum guide rail mounting groove 61, or only on the upper vacuum guide rail 41, or a portion of the elastic element mounting groove can be provided on both the vacuum guide rail mounting groove 61 and the upper vacuum guide rail 41. The first elastic element 52 is installed in the elastic element mounting groove. The connection structure between the lower vacuum guide rail 42 and the vacuum guide rail mounting groove 61 is exactly the same as the connection structure between the upper vacuum guide rail 41 and the vacuum guide rail mounting groove 61 described above, and will not be repeated here.

[0054] The vacuum guide rail is in a floating state via the floating component 5. The spring force is adjusted by adjusting bolts and springs to ensure a tight fit between the side of the vacuum guide rail and the side of the sliding seat 2. The vacuum guide rail consists of upper and lower groups that work together on the same molding module, which not only increases the vacuum flow rate but also prevents poor molding due to channel blockage.

[0055] Mounting base 1 includes an upper mounting plate 11 and a lower mounting plate 12. The upper vacuum guide rail 41 is mounted on the upper mounting plate 11, and the lower vacuum guide rail 42 is mounted on the lower mounting plate 12. Vacuum guide rail mounting bases 6 are fixed on the upper mounting plate 11 and the lower mounting plate 12 respectively.

[0056] like Figure 8 and Figure 9As shown, a vacuum guide rail limiting assembly 7 is provided on the vacuum guide rail. The vacuum guide rail limiting assembly 7 includes a fixing pin 71, an upper bearing 72, and a lower bearing 73. The fixing pin 71 is fixedly installed on the vacuum guide rail and extends out at both ends. The upper bearing 72 and the lower bearing 73 are respectively fixedly installed on the two extended ends. The circumferential surfaces of the upper bearing 72 and the lower bearing 73 abut against the side of one of the vacuum guide rail mounting seats 6. When the sliding seat 2 moves forward along the production direction S, the vacuum guide rail abutting against the sliding seat 2 is subjected to friction. This friction will cause the vacuum guide rail to tend to move in the production direction with the sliding seat 2, that is, in Figure 8 The vacuum guide rail limiting component 7 not only prevents the vacuum guide rail from moving to the right, but also ensures that the floating component 5 works properly. This is because once the vacuum guide rail moves to the right with the sliding seat 2, the spring of the floating component 5 will press against one side of the bolt 51, causing the floating component 5 to malfunction and lose its floating state.

[0057] like Figure 4 and Figure 5 As shown, the upper vacuum guide rail 41 is used as an example for explanation. The upper vacuum guide rail 41 includes two vacuum guide rail blocks, designated as the first vacuum guide rail block 411 and the second vacuum guide rail block 412. Each vacuum guide rail block has a guide rail vacuum cavity. The first vacuum guide rail block 411 has two guide rail vacuum cavities, designated as upper guide rail vacuum cavity one 4111 and upper guide rail vacuum cavity two 4112. The second vacuum guide rail block 412 has one guide rail vacuum cavity, designated as upper guide rail vacuum cavity three 4121. Adjacent vacuum guide rail blocks are fixedly connected by connectors 413, and the guide rail vacuum cavities of each vacuum guide rail block are not interconnected. The connectors 413 are preferably designed as connecting pins, but adjacent vacuum guide rail blocks can also be welded together. The structure of the lower vacuum guide rail 42 is the same as that of the upper vacuum guide rail 41, and the lower vacuum guide rail 42 has lower guide rail vacuum cavity one, lower guide rail vacuum cavity two, and lower guide rail vacuum cavity three. The vacuum guide rail is designed with multiple vacuum chambers to control the vacuum level. The vacuum level of each chamber is adjusted and controlled separately according to the forming changes during the tube forming process. The vacuum chambers of each guide rail do not affect each other, and it is easy to troubleshoot problems in different areas if a problem occurs in the vacuum system.

[0058] The upper vacuum guide rail 41 and the lower vacuum guide rail 42 are provided with an inlet guide slope X, which facilitates the sliding seat 2 to enter the molding channel area and fit tightly against the sides of the upper vacuum guide rail 41 and the lower vacuum guide rail 42. This allows the upper ventilation channel 21 of the sliding seat to be connected to the guide rail ventilation channel 43 of the upper vacuum guide rail 41, and the lower ventilation channel 22 of the sliding seat to be connected to the guide rail ventilation channel 43 of the lower vacuum guide rail 42.

[0059] Of course, the number of vacuum guide blocks can also be set to three, four, etc. The specific number can be set according to the length of the double-wall corrugated pipe to be produced. The longer the length of the double-wall corrugated pipe to be produced, the more vacuum guide blocks are required.

[0060] like Figures 2 to 5 As shown, the vacuum system includes multiple vacuum cylinders 8, which are fixed on the mounting base 1. In this example, it is preferable to set two vacuum cylinders 8 on the mounting base 1 of each platform. These are designated as the first vacuum cylinder 81 and the second vacuum cylinder 82. Along the production direction S, the first vacuum cylinder 81 is located upstream of the second vacuum cylinder 82. The vacuum cylinder is divided into several internal vacuum chamber areas, which correspond one-to-one with the guide rail vacuum chambers. The corresponding internal vacuum chamber areas and guide rail vacuum chambers are connected by external vent pipes, and a vacuum gauge is installed on the external vent pipes between them. For example, the first vacuum cylinder 81 is divided into two internal vacuum chamber areas, designated as internal vacuum chamber area one and internal vacuum chamber area two. The second vacuum cylinder 82 has one internal vacuum chamber area, designated as internal vacuum chamber area three. The upper guide rail vacuum chamber one 4111 and the lower guide rail vacuum chamber one are connected to internal vacuum chamber area one through an external vent pipe. The upper guide rail vacuum chamber two 4112 and the lower guide rail vacuum chamber two are connected to internal vacuum chamber area two through an external vent pipe. The upper guide rail vacuum chamber three 4121 and the lower guide rail vacuum chamber three are connected to internal vacuum chamber area three through an external vent pipe. Of course, the vacuum system can also be configured with three or four equal vacuum cylinders, and the specific number of vacuum cylinders can be designed according to needs.

[0061] First, the vacuum cylinder can act as a buffer for vacuum. When making plastic corrugated pipes with super-strong flaring, the amount of vacuum leakage is relatively large, and a large amount of vacuum suction is required. If the traditional structure of direct connection between vacuum pump and flaring is still used, the pipe forming will be poor.

[0062] Furthermore, the vacuum cylinder is divided into several internal vacuum chamber zones, each corresponding to a guide rail vacuum chamber. These zones are connected by external air vents and vacuum gauges. The vacuum gauges monitor the vacuum level, allowing for timely detection of insufficient vacuum in each molding module during molding. This facilitates individual adjustment and control of the vacuum level in each molding module, ensuring that the vacuum levels of different modules do not interfere with each other. Simultaneously, it facilitates timely troubleshooting of blockages, leaks, and other abnormal operating conditions.

[0063] In some embodiments, the vacuum system includes a hinged frame 9, which is fixed below the mounting base 1. The hinged frame 9 has a closed frame ventilation chamber, and the vacuum cylinder is connected to the frame ventilation chamber through an external ventilation pipe. In this embodiment, the hinged frame 9 is preferably a square frame, which is composed of four hollow rectangular steel pipes that enclose the aforementioned frame ventilation chamber.

[0064] Existing molding machine vacuum systems require numerous external pipes (also known as external vacuum hoses or external pipes). During the molding process, some of these external pipes move, requiring cable chains for support. Furthermore, some external pipes need to be installed within the molding machine's opening and closing frame. This not only involves numerous external pipes but also makes the process complex and time-consuming, as it places some of them within the cable chains and frame. The vacuum system of this invention features an opening and closing frame 9 with a closed vent chamber, which itself acts as a vacuum conduit. This eliminates the need to install external pipes within the frame, simplifying installation and reducing costs.

[0065] In some embodiments, such as Figure 13 As shown, the vacuum system includes several vacuum pumps 10. The vacuum pumps 10 are connected to the opening / closing frame 9 via selectable connecting or disconnectable pipe assemblies. These selectable connecting or disconnectable pipe assemblies include a static pipe assembly J and a moving pipe assembly V. The static pipe assembly J is connected to the vacuum pumps. The operating platform includes a base frame 100. The opening / closing frame 9 can slide relative to the base frame 100. The moving pipe assembly V is fixedly connected to the opening / closing frame 9. When the moving pipe assembly V slides to the working position with the opening / closing frame 9, it seals and connects with the static pipe assembly J. The aforementioned static pipe assembly J and moving pipe assembly V adopt a butt-joint connection structure, avoiding the previous method of dragging a large number of external pipes simultaneously by a cable chain when the molding machine moves back and forth. This reduces the power pressure and prevents repeated bending of the external pipes during movement, thus avoiding damage to the external pipes and reducing pipe maintenance costs. Furthermore, it significantly reduces the number of external pipes, greatly reducing the overall production space occupied by the external pipes and avoiding serious potential safety hazards on-site.

[0066] The static piping assembly J includes a connector mounting base 101 and a floating pipe connector 102 that can slide relative to the connector mounting base 101. An elastic floating structure is provided between the connector mounting base 101 and the floating pipe connector 102. The dynamic piping assembly V is configured as a flexible hose connector 103.

[0067] Preferably, such as Figure 14 As shown, the elastic floating structure includes a connecting guide rod 104, a second elastic element 105, and a limiting structure. The limiting structure includes a first limiting baffle 1021 fixedly connected to the connector mounting base 101, a second limiting baffle 1022 fixedly connected to the floating pipe connector 102, and a limiting nut 1023. One end of the connecting guide rod 104 is fixedly connected to the second limiting baffle 1022, and the other end of the connecting guide rod 104 passes through the first limiting baffle 1021 and is threadedly connected to the limiting nut 1023. The second elastic element 105 is sleeved on the connecting guide rod 104 and located between the first limiting baffle 1021 and the second limiting baffle 1022.

[0068] like Figures 13 to 15 As shown, the static pipeline assembly J includes a central vacuum tube 107 connected to the floating pipe joint 102, a vacuum distributor joint 108, multiple first vacuum branch pipes 1091, and multiple second vacuum branch pipes 1092. The forming machine includes a sizing sleeve D, which has a sizing vacuum chamber. The vacuum distributor joint 108 is connected to multiple first vacuum branch pipes 1091, the central vacuum tube 107, and multiple second vacuum branch pipes 1092. The vacuum pump 10 is connected to the vacuum distributor joint 108 through the first vacuum branch pipes 1091. The central vacuum tube 107 is fixedly connected to the floating pipe joint 102. The multiple second vacuum branch pipes 1092 are connected to the sizing vacuum chamber.

[0069] The forming principle of plastic double-wall corrugated pipe is briefly described below: When forming module 3 moves to the forming zone, the two forming modules 3 in opposite positions close together to form the forming mold of the outer tube. The sizing sleeve D is located between the forming molds of the outer tube. The sizing sleeve D is fixedly connected to the extruder head. Simply put, the plastic raw material is first heated and plasticized by the plastic extruder and transformed into a molten state. The molten plastic material passes through the extruder head, which extrudes two tube blanks with different diameters and tube shapes. The larger diameter tube blank will eventually become the outer tube wall of the plastic double-wall corrugated pipe, and the smaller diameter plastic tube blank will eventually become the inner tube wall of the plastic double-wall corrugated pipe. The plastic double-wall corrugated pipe is formed under the combined action of the forming mold of the outer tube and the sizing sleeve D. The outer tube blank is formed by vacuum action, tightly adhering to the inner cavity of the forming module 3 in the forming zone. At the same time, the inner tube blank is adsorbed and stretched along the outer circumference of the sizing sleeve D by vacuum action and bonded to the outer tube blank. In this way, the two layers of plastic are bonded together to form the plastic double-wall corrugated pipe.

[0070] The vacuum pump 10 is connected to the molding module 3 via a vacuum distributor connector 108, a static pipe assembly J, a dynamic pipe assembly V, a first vacuum branch pipe 1091, and the frame ventilation chamber of the opening and closing frame, greatly reducing the number of external ventilation pipes. The vacuum pump 10 is connected to the sizing sleeve D via the vacuum distributor connector 108 and the second vacuum branch pipe 1092, which connects to the sizing vacuum chamber, further reducing the number of external pipelines. Therefore, the required production space is reduced, avoiding serious hidden dangers to on-site production safety.

[0071] Vacuum system operation process: The vacuum pump operates, and the vacuum flow enters the frame ventilation chamber of the opening and closing frame 9 through the selectable connected or disconnectable pipe assembly (the selectable connected or disconnectable pipe assembly is in the connected state during operation), and then enters the vacuum cylinder. The vacuum flow in the vacuum cylinder goes to the upper vacuum guide rail and the lower vacuum guide rail through the external ventilation pipe. Then, the vacuum flow enters the module ventilation channel 31 on the forming module 3 through the upper ventilation channel 21 of the sliding seat and multiple lower ventilation channels 22 of the sliding seat for forming the outer wall of the pipe.

[0072] The vacuum system of the plastic double-wall corrugated pipe forming machine of the present invention can not only meet the forming of plastic corrugated pipes with super strong flaring, making the pipes full and beautiful in appearance, but can also be used for forming other large-specification pipes that require a large amount of vacuum.

[0073] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A vacuum system for a plastic double-wall corrugated pipe forming machine, the forming machine comprising two operating platforms arranged opposite to each other and operating synchronously, each operating platform comprising a mounting base, the mounting base being provided with an annular track, and a forming module fixed on a sliding base and running along the annular track via the sliding base, characterized in that: The vacuum system includes a vacuum guide rail, a module ventilation channel disposed on the molding module, and a sliding seat ventilation channel disposed on the sliding seat, wherein the module ventilation channel is connected to the sliding seat ventilation channel; The vacuum guide rail is located in the forming channel area of ​​the running platform and is floatingly connected to the mounting base through a floating component. The vacuum guide rail floats along the mold opening and closing direction. The sliding seat ventilation channel includes multiple upper sliding seat ventilation channels and multiple lower sliding seat ventilation channels; The vacuum guide rail includes an upper vacuum guide rail and a lower vacuum guide rail, and the upper vacuum guide rail and the lower vacuum guide rail are each provided with multiple guide rail ventilation channels. When molding a double-walled corrugated plastic pipe, the molding module involved in the molding moves to the molding channel area along with the sliding seat. The sliding seat located in the molding channel area compresses the floating component so that the side of the vacuum guide rail fits tightly against the side of the sliding seat. At the same time, the upper air passage of the sliding seat is connected to the guide rail air passage of the upper vacuum guide rail, and the lower air passage of the sliding seat is connected to the guide rail air passage of the lower vacuum guide rail. The vacuum guide rail includes at least two vacuum guide rail blocks, each of which has a guide rail vacuum cavity. Adjacent vacuum guide rail blocks are fixedly connected by connectors, and the guide rail vacuum cavities of each vacuum guide rail block are not interconnected. The vacuum system includes multiple vacuum cylinders, which are fixed on the mounting base. Each vacuum cylinder is divided into several internal vacuum chamber areas, which correspond one-to-one with the guide rail vacuum chamber. The corresponding internal vacuum chamber areas and the guide rail vacuum chambers are connected by an external vent pipe, and a vacuum gauge is installed on the external vent pipe between them. The vacuum system includes an opening and closing frame, which is fixed below the mounting base. The opening and closing frame has a closed frame ventilation chamber, and the vacuum cylinder is connected to the frame ventilation chamber through an external ventilation pipe.

2. The vacuum system of the plastic double-wall corrugated pipe forming machine as described in claim 1, characterized in that: The molding module includes a molding module body and a module base plate, which are fixedly connected. The module ventilation channel includes a main vacuum channel assembly disposed on the molding module body and a module base plate vacuum cavity disposed on the module base plate. The main vacuum channel assembly includes several arc-shaped vacuum pipes and a transition vacuum channel located inside the molding module body, multiple vacuum slots opened at the molding cavity, and multiple side holes opened at the main side wall of the molding module. The side holes connect the arc-shaped vacuum pipes and the vacuum slots. The transition vacuum channel connects the arc-shaped vacuum pipes and the module base plate vacuum cavity respectively. The module base plate vacuum cavity includes a base plate vacuum cavity connected to the upper ventilation channel of the sliding seat and a base plate lower vacuum cavity connected to the lower ventilation channel of the sliding seat.

3. The vacuum system of the plastic double-wall corrugated pipe forming machine as described in claim 1, characterized in that: The floating assembly includes a bolt and a first elastic element. The mounting base is fixed with a plurality of spaced vacuum guide rail mounting bases. The vacuum guide rail mounting base is provided with a vacuum guide rail mounting groove. The first elastic element is provided between the vacuum guide rail mounting groove and the vacuum guide rail. The bolt passes through the first elastic element to connect the vacuum guide rail mounting base and the vacuum guide rail.

4. The vacuum system of the plastic double-wall corrugated pipe forming machine as described in claim 3, characterized in that: The vacuum guide rail is provided with a vacuum guide rail limiting assembly, which includes a fixing pin, an upper bearing, and a lower bearing. The fixing pin is fixedly installed on the vacuum guide rail and extends out at both ends. The two extended ends are respectively fixedly installed with the upper bearing and the lower bearing. The circumferential surfaces of the upper bearing and the lower bearing are abutted against the side of one of the vacuum guide rail mounting seats.

5. The vacuum system of the plastic double-wall corrugated pipe forming machine as described in claim 1, characterized in that: The vacuum system includes several vacuum pumps, which are connected to the opening and closing frame via a piping assembly that can be selectively connected or disconnected. The selectable connecting or disconnecting piping assembly includes a static piping assembly and a moving piping assembly. The static piping assembly is connected to the vacuum pump. The operating platform includes a base frame. The opening and closing frame can slide relative to the base frame. The moving piping assembly is fixedly connected to the opening and closing frame. When the moving piping assembly slides to the working position with the opening and closing frame, it is sealed and connected to the static piping assembly.

6. The vacuum system of the plastic double-wall corrugated pipe forming machine as described in claim 5, characterized in that: The static pipe assembly includes a connector mounting base and a floating pipe connector that can slide relative to the connector mounting base. An elastic floating structure is provided between the connector mounting base and the floating pipe connector. The dynamic pipe assembly is configured as a flexible hose connector.

7. The vacuum system of the plastic double-wall corrugated pipe forming machine as described in claim 6, characterized in that: The static piping assembly includes a central vacuum tube connected to a floating pipe joint, a vacuum distributor joint, multiple first vacuum sub-pipes, and multiple second vacuum sub-pipes. The forming machine includes a sizing sleeve with a sizing vacuum chamber. The vacuum distributor joint is connected to multiple first vacuum sub-pipes, the central vacuum tube, and the multiple second vacuum sub-pipes. The vacuum pump is connected to the vacuum distributor joint through the first vacuum sub-pipes. The central vacuum tube is fixedly connected to the floating pipe joint. The multiple second vacuum sub-pipes communicate with the sizing vacuum chamber.

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