A conventional blow-molded oil tank enclosure welded wave-breaking plate and welding method thereof

Abstract

The invention relates to a conventional blow-molded fuel tank enclosure welded wave-breaking plate, the wave-breaking plate comprising an enclosure, a connecting plate, weight-reducing holes and welding columns, the enclosure being connected via the connecting plate, the connecting plate being provided with weight-reducing holes, and the welding columns being provided on the wave-breaking plate connecting plate; the enclosure welded wave-breaking plate of the technical solution adopts an enclosure type structure to significantly increase its strength and prolong its service life compared with a sheet type structure; the problem of limited arrangement of the fuel tank under the chassis of the automobile is solved, and the enclosure welded wave-breaking plate can be designed to solve the noise reduction problem regardless of whether it is longitudinally or transversely arranged, and has a wide range of applications.

Description

Technical Field

[0001] The invention relates to a wave-breaking plate, in particular to a conventional blow-molding process-formed enclosing plate welded wave-breaking plate for an oil tank, and belongs to the technical field of hollow body structural components. Background Art

[0002] The sloshing of liquid fuel in the fuel tank of a car will produce fuel sloshing noise, which is specifically manifested as the sound produced by the liquid fuel hitting the inner wall of the fuel tank or the built-in parts of the fuel tank when the vehicle accelerates or decelerates. In order to reduce fuel sloshing and reduce noise, the following solutions are currently commonly used: adding deep groove features, i.e., blow molding features, to the upper or lower surface of the fuel tank to reduce noise; adding inverted triangle features to the upper surface of the fuel tank is intended to instantly break up the waves during the sloshing process, so that its energy is dispersed and noise is reduced; of course, the most widely used and effective method is to arrange wave-breaking plates in the fuel tank to achieve an immediate noise reduction effect. The main function of the wave-breaking plate is to reduce the kinetic energy generated by the liquid when the vehicle accelerates or decelerates, reduce the relative movement speed of the liquid, and thus reduce the impact of the liquid on the surface of the fuel tank and the sound generated by the collision of the liquid itself. However, for the traditional blow-molded fuel tank, the existing technology is to weld sheet wave-breaking plates inside the fuel tank. Most fuel tanks are rectangular, and most OEMs will place the fuel tank horizontally under the chassis of the car. This arrangement is relatively good and will reduce the noise generated by vehicle acceleration or deceleration, climbing or descending. The so-called horizontal placement means that the length direction of the fuel tank is perpendicular to the forward direction of the vehicle coordinate system, that is, the -X direction. Figure 1 At this time, the sheet-shaped welded anti-wave plate is perpendicular to the flow direction of the oil when it is placed horizontally in the oil tank, so it will have a significant noise reduction effect, see Figure 2. However, many OEMs still place the oil tank vertically at the bottom of the car due to chassis layout reasons. At this time, the sheet-shaped anti-wave plate is parallel to the flow direction of the oil and obviously has no noise reduction effect, see Figure 3 Therefore, it is urgent to invent and design a new type of welded wave-breaking plate for the traditional blow-molded fuel tank, which can achieve a significant noise reduction effect regardless of whether the OEM places the fuel tank horizontally or vertically under the chassis. Summary of the invention

[0003] The present invention is a welded wave-breaking plate designed for a conventional blow-molded fuel tank. The wave-breaking plate can not only meet the requirements of the conventional blow-molding process and achieve the purpose of noise reduction, but also solve the problem of limited placement direction of the fuel tank at the bottom of the car.

[0004] In order to achieve the above-mentioned purpose, the technical solution of the present invention is as follows: a conventional blow-molded oil tank enclosure welded wave-breaking plate, characterized in that the wave-breaking plate is an integral injection molded part including an enclosure, a connecting plate, a weight-reducing hole and four welding columns, the enclosure is connected by a connecting plate, the connecting plate is provided with a weight-reducing hole, and the four welding columns are provided on the connecting plate. The connecting plate is provided with two limit holes of different sizes in the X direction.

[0005] As an improvement of the present invention, the enclosure is set to be rectangular and square, the clearance between the enclosure Z and the upper and lower inner walls of the oil tank is required to be no less than 25mm, and the clearance between the enclosure and the oil tank in the X and Y directions, i.e. the side walls of the oil tank, is required to be no less than 80mm.

[0006] As an improvement of the present invention, the number of the welded columns is at least 4, which are symmetrically arranged on the wave-breaking board.

[0007] As an improvement of the present invention, the connecting plate is provided with weight-reducing holes of different sizes, the main purpose of which is to reduce the cost of injection molding materials for the wave-breaking plate. Reinforcement ribs are arranged around each weight-reducing hole to increase strength and avoid cracking caused by thin walls.

[0008] As an improvement of the present invention, the welded column includes a column body, reinforcing ribs, 4 oil leakage holes, 4 long waist holes, a welding pitting plate, an exhaust overflow groove and an exhaust hole. The reinforcing ribs are evenly arranged around the column body, the pitting plate is provided with exhaust holes and an exhaust overflow groove, and the long waist holes are evenly distributed around the pitting plate.

[0009] As an improvement of the present invention, 4 oil leakage holes are designed inside each reinforcing rib enclosure. The purpose is to prevent the oil from accumulating on the upper part of the connecting plate, thereby reducing the available oil volume; 4 equally divided long waist holes are designed on each pitting plate. The purpose is to increase the flexibility of the pitting plate itself. It can ensure that after the normal temperature wave-breaking plate and the high temperature 200° oil tank blank are molded together, the pitting plate has enough flexibility to complete the cold shrinkage process in all directions together with the oil tank.

[0010] As an improvement of the present invention, the distance between the centers of the two pitting disks in the X and Y directions needs to be reduced in both the X and Y directions, and this shrinkage rate is the shrinkage rate of the oil tank in cold shrinkage, and the specific value is 3%; the Z direction is reduced in accordance with the Z direction of the oil tank, and the value is 2.5%; the number of pits N on the pitting disk 45 is determined by calculating the welding pull-out force F between each pitting disk and the inner wall of the oil tank according to the verification requirements, and the pull-out force that each pit can withstand is 25.2N, and the number of pits N=F / 25.2.

[0011] As an improvement of the present invention, the wave-breaking plate further includes two upper and lower mandrel limiting holes, and the mandrel limiting holes are arranged on the connecting plate.

[0012] As an improvement of the present invention, the push rod limiting hole is set to a D-shaped size, and the outer size of the upper D-shaped hole is smaller than that of the lower D-shaped hole.

[0013] A method for welding a wave-breaking plate by welding a panel, the method comprising the following steps: first, placing the wave-breaking plate on a push rod lifting device by a manipulator, the push rod lifting device having a lifting function under the action of a cylinder, and its D-shaped shape needs to be consistent with the shape of a limiting hole of the wave-breaking plate to achieve the purpose of stopping rotation, and two steps 61 and 62 are arranged on the push rod lifting device to cooperate with the upper and lower side holes of the limiting hole respectively to achieve the purpose of upper and lower limiting; when the blank goes down, the push rod will synchronously rise vertically under the action of the cylinder to transport the wave-breaking plate into the blank, and when the position of the pitting plate is horizontally aligned with the position of the pitting welding inner wall in the left and right oil tank blow molding molds, the mold is immediately closed, and the fusion welding process of the pitting of the wave-breaking plate and the pitting welding inner wall of the oil tank is completed during the mold closing process, and before the left and right molds are completely closed, the push rod lifting device 6 needs to be immediately retracted to the outside of the oil tank body under the action of the cylinder.

[0014] Compared with the sheet-welded wave-breaking board technology used in the existing traditional blow-molded fuel tanks, the present invention has the following advantages: 1) The welded wave-breaking board adopts a sheet-like structure, which significantly increases its strength and service life compared to the sheet-like structure. 2) It solves the problem of limited layout of the fuel tank under the chassis of the car. Whether it is placed longitudinally or horizontally, the welded wave-breaking board can be designed to solve the noise reduction problem. 3) The welded column structure on the sheet-like wave-breaking board can ensure its strength and the flexibility of the pockmark disk to solve its cold shrinkage problem, avoid the pitting welding defects caused by insufficient shrinkage, and increase the service life of the wave-breaking board. 4) The welding process of the welded wave-breaking board is both popular and feasible, and can ensure the quality of the pockmark welding of the entire wave-breaking board, and ensure the functional stability of the wave-breaking board. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 This is a detailed drawing of the vehicle coordinate system;

[0016] Figure 2-1 — Figure 2-3 It is a schematic diagram of a conventional sheet-shaped welded wave-breaking plate and a transversely placed fuel tank;

[0017] Figure 3 It is a schematic diagram of a conventional longitudinally arranged sheet-shaped welded wave-breaking plate;

[0018] Figure 4 , Figure 5 , Figure 6 It is a schematic diagram of the overall structure of the present invention;

[0019] Figure 7 It is a schematic diagram of the structure of different sides of the present invention;

[0020] Figure 8 This is a schematic diagram of the welding column structure;

[0021] Fig. 9 , Fig.10 Schematic diagram of the wave-breaking plate welding process;

[0022] Fig.11 Schematic diagram of the jack lifting device.

[0023] In the figure: 1. enclosure, 2. connection plate, 3. weight reduction hole, 4. welding column, 5. limit hole of mandrel, 6. mandrel lifting device,

[0024] 41. Column body, 42. Reinforcement ribs, 43. Oil leakage hole, 44. Long waist hole, 45. Welded pitting plate, 46. Exhaust overflow groove, 47. Exhaust hole, 61. First step, 62. Second step, 7. Fuel tank body, 8. Oil pump, 9. Surrounding plate welded wave-breaking plate, 10. Traditional blow-molded fuel tank, 11. Sheet welded wave-breaking plate, 12. Fuel tank blank, 13. Left half mold, 14. Right half mold. DETAILED DESCRIPTION

[0025] Example 1: See Figure 4-Figure 6 A conventional blow-molded oil tank enclosure welded wave-breaking plate, the wave-breaking plate is an integral injection molded part, comprising an enclosure 1, a connecting plate 2, a weight-reducing hole 3 and four welding columns 4. The enclosure 1 is connected via the connecting plate 2, the connecting plate is provided with a weight-reducing hole 3, and the four welding columns are provided on the connecting plate. The connecting plate is provided with two limiting holes 5 of different sizes in the X direction, see Figure 5 ; The oil tank in this embodiment is placed vertically under the chassis of the car; In the above scheme, the enclosure 1 is the main part of the wave-breaking plate and is used to realize the noise reduction function of the wave-breaking plate. The layout principle of the enclosure 1 in the oil tank is that it must avoid the built-in components of the oil tank. For traditional blow-molded oil tanks, the built-in components are only oil pumps and valves and both are assembled later, among which the oil pump 8 is relatively large. Therefore, the enclosure welded wave-breaking plates are mainly divided into two categories. The first category is that the entire enclosure area is away from the oil pump and maintains a clearance requirement of ≥25mm with the float. The second category is that the enclosure surrounds the entire oil pump, that is, the entire oil pump is finally assembled in the largest weight-reducing hole 3, and ensures that the inner wall reinforcement ribs of the weight-reducing hole and the oil pump float maintain a clearance requirement of ≥25mm. This scheme is described in detail using the first category as an example.

[0026] The larger the length and width of the outer contour of the enclosure 1 and the higher the height, the easier it is to hinder the flow of liquid, and the more obvious the noise reduction effect. Therefore, the design principle of the enclosure 1 is to maximize the size while meeting the clearance requirements with the inner wall of the fuel tank. The enclosure is generally designed to be rectangular or square. Taking into account the size of the die and process limitations of the blow-molded fuel tank billet, the clearance between the upper and lower sides of the enclosure and the upper and lower inner walls of the fuel tank is required to be no less than 25mm. The clearance between the enclosure and the fuel tank in the X and Y directions, that is, the side walls of the fuel tank, is required to be no less than 80mm. When designing a wave-breaking plate, in addition to meeting the noise reduction effect, it is also necessary to consider minimizing the cost of wave-breaking plate materials. Therefore, at the beginning of the design of the wave-breaking plate, it is necessary to clarify whether the fuel tank is installed longitudinally or horizontally. If it is installed horizontally, the width W of the enclosure can be appropriately reduced. If it is installed longitudinally, the length L of the enclosure can be appropriately reduced, as shown in this embodiment. Figure 4 As shown. The enclosure 1 is provided with an indefinite number of round holes and waist-shaped holes for the normal flow of oil. There are no special requirements for the hole size and gap, only the uniform design is required to ensure the smooth flow of oil. The enclosure thickness is generally designed to be around 2.5mm. Compared with the sheet-shaped anti-wave plate, the enclosure welded anti-wave plate has a significant advantage in structural strength. Therefore, the slightly higher cost can be compensated by appropriately reducing the wall thickness. Figure 4 .

[0027] The connecting plate 2 is the main structure of the injection molding, which is used to connect the connecting panels 1 to maintain the overall structural stability of the anti-wave plate. Its thickness of 2mm is sufficient and can reduce the cost of injection molding materials. The connecting plate 2 needs to be designed with weight-reducing holes 3 of different sizes, the main purpose of which is to reduce the cost of injection molding materials for the anti-wave plate. Reinforcement ribs 31 need to be set around each weight-reducing hole to increase strength and avoid cracking caused by thin walls. Figure 6 The height of the reinforcing rib 31 is about 5mm and the thickness is 2mm. The maximum weight reduction hole set in the center of the connecting plate not only plays a role in weight reduction, but also serves as a reserved space for the assembly of the top rod lifting device 6 and the two limit holes in the X direction of the wave-breaking plate to avoid interference. When designing the second type of welded wave-breaking plate mentioned above, the built-in oil pump will be installed exactly in the maximum weight reduction hole in the center of the connecting plate, and the oil pump float must ensure a safety gap of ≥25mm with the reinforcing rib 31 on the weight reduction hole.

[0028] The number of welding columns 4 in the present invention must be 4, with two on each side evenly and symmetrically distributed on the wave-breaking board. When the pitting of the wave-breaking board and the pitting welding surface of the inner wall of the fuel tank are welded and fused, the welding columns can maintain the stability of the wave-breaking board in the fuel tank and increase its service life. The spacing value of the two welding columns along the X direction of the automobile coordinate system is x1, and the spacing value of the Y direction is y1. The spacing value of the upper and lower pitting disk surfaces in the Z direction is z1, see Figure 7 . Furthermore, considering that the normal temperature wave-breaking plate will shrink together with the inner wall of the fuel tank with a temperature of up to 200° after being melted and welded, the x1, y1 and z1 values ​​of the wave-breaking plate need to take into account the shrinkage rate when shrinking together with the fuel tank when designing the wave-breaking plate. After the fuel tank is cooled, that is, in the theoretical state at room temperature, the theoretical spacing value of the inner wall pitted disk welding center along the X direction of the automobile coordinate system is x2, the spacing in the Y direction is y2, and the spacing in the Z direction of the upper and lower inner wall pitted welding surfaces is z2. The fuel tank blow molding mold must be manufactured after the shrinkage rate is released in all directions according to the theoretical data state of the fuel tank. The theoretical spacing value of the inner wall pitted disk welding center on the fuel tank mold along the X direction of the automobile coordinate system is X2, the Y direction is Y2, and the Z direction distance between the upper and lower inner wall pitted welding surfaces is Z2. The relationship is as follows:

[0029] x1=X2=(1+3%)x2, y1=Y2=(1+3%)y2, z1=Z2=(1+2.5%)z2. (3% and 3% are the shrinkage rates of the oil tank blow mold in the X and Y directions respectively, and 2.5% is the shrinkage rate in the Z direction).

[0030] See also Figure 8 In this solution, the welding column 4 includes a column body 41, a reinforcing rib 42, an oil leakage hole 43, a long waist hole 44, a welding pitting plate 45, an exhaust overflow groove 46 and an exhaust hole 47. The reinforcing rib 42 needs to be arranged around the column body and is generally designed in a fence shape. Four oil leakage holes 43 are designed inside each reinforcing rib enclosure to prevent oil from accumulating on the upper part of the connecting plate, thereby reducing the available oil volume. A exhaust hole 47 required for the production process is designed at the center of each pitting plate 45, and the diameter is generally An exhaust overflow groove 46 is required between every two or three rows of pits, with a groove depth of ≥1mm and a groove width of ≥2mm. The thickness of the pitting plate is generally between 3.0-3.5mm. The pits on each pitting plate 45 are evenly arranged in a circular scattered distribution, and the pit diameter is The height of the pit is 1.75mm. The number of pits N is determined by calculating the welding pull-out force F between the pit plate and the inner wall of the fuel tank. The F value is determined comprehensively based on the weight of each wave-breaking plate, the available volume of the fuel tank and the shape of the fuel tank. The pull-out force that each pit can withstand is 25.2N, and the number of pits N = F / 25.2N. When the left and right molds of the fuel tank are closed, the pits will all be integrated into the pit welding surface of the inner wall of the fuel tank at high temperature to complete the welding process. Each pit plate will be designed with 4 equally divided long waist holes 44, the purpose of which is to increase the flexibility of the pit plate 45 itself. It can ensure that after the normal temperature wave-breaking plate and the high temperature fuel tank blank of 200° are closed, the pit plate has enough flexibility to complete the cold shrinkage process in all directions together with the fuel tank.

[0031] See also Figure 5 The wave-breaking plate also includes a push rod limiting hole 5, which is arranged on the connecting plate 2. The push rod limiting hole is arranged in a D shape. From the blank cutting direction, the upper D-shaped hole is smaller than the lower D-shaped hole.

[0032] Fig. 9 The invention illustrates how to weld and fix the enclosure welded wave-breaking plate in the process of traditional oil tank blow molding. The invention discloses a method for welding the enclosure welded wave-breaking plate. The method comprises the following steps: first, the wave-breaking plate is placed on the push rod lifting device 6 by a manipulator. The push rod lifting device 6 is lifted and lowered under the action of the cylinder. The rod-shaped cross-sectional profile of the push rod lifting device 6 must also be a D-shaped shape and must be consistent with the shape of the limiting hole 5 of the wave-breaking plate to prevent rotation. Two steps, namely the first step 61 and the second step 62, are arranged on the push rod lifting device 6 to cooperate with the upper and lower side holes of the limiting hole to achieve the upper and lower limiting purposes, see Fig.10When the blank 12 moves downward, the ejector lifting device 6 is synchronously and vertically raised into the hot tank blank under the action of the cylinder. When the pitting plate is raised to align horizontally with the pitting positions in the left and right blow molds 13 and 14, the program automatically starts the mold closing instruction. During the mold closing process of the left and right molds, all the pittings on the four pitting plates of the wave-breaking plate are simultaneously fused and welded with the four pitting welding surfaces of the inner wall of the tank. Before the left and right molds are completely closed, the ejector lifting device 6 is immediately withdrawn to the outside of the tank body under the action of the cylinder.

[0033] It should be noted that the above embodiments are not intended to limit the protection scope of the present invention, and equivalent changes or substitutions made on the basis of the above technical solutions all fall within the protection scope of the claims of the present invention.

Claims

1. A conventional blow-molded fuel tank enclosure welded wave-breaking plate, characterized in that: The anti-wave plate comprises a shroud, a connecting plate, a weight-reducing hole and a welding column. The shroud is connected by the connecting plate, the connecting plate is provided with a weight-reducing hole, and the welding column is provided on the anti-wave plate connecting plate. The enclosure is set to be rectangular or square, and the clearance between the enclosure in the Z direction and the upper and lower inner walls of the oil tank is required to be no less than 25 mm, and the clearance between the enclosure and the oil tank in the X and Y directions and the side wall of the oil tank is required to be no less than 80 mm; The number of the welded columns is at least 4, which are symmetrically arranged on the upper and lower sides of the wave-breaking board. The connecting plate is provided with weight-reducing holes, and reinforcing ribs are arranged around each weight-reducing hole. The welded column includes a column body, reinforcing ribs, 4 oil leakage holes, 4 long waist holes, a welding pitting plate, an exhaust overflow groove and an exhaust hole. The reinforcing ribs are evenly arranged around the column body, the pitting plate is provided with exhaust holes and exhaust overflow grooves, and the waist holes are evenly distributed around the pitting plate; The distance between the centers of the two pitting disks in the X and Y directions needs to set the shrinkage rate in both the X and Y directions. This shrinkage rate is the shrinkage rate of the oil tank, and the specific value is 3%; the Z direction sets the shrinkage rate according to the oil tank Z direction, and the value is 2.5%; the number of pits N on the pitting disk should be calculated and determined according to the welding pull-out force F of each pitting disk and the inner wall of the oil tank required by the verification. The pull-out force that each pit can withstand is 25.2N, and the number of pits N=F / 25.2, The anti-wave plate also includes two upper and lower mandrel limiting holes, and the mandrel limiting holes are arranged on the connecting plate. The limit hole of the push rod is set to a D-shaped size, and the outer size of the upper D-shaped hole is smaller than that of the lower D-shaped hole. The maximum weight reduction hole set in the center of the connecting plate is also used as a reserved space for the assembly of the top rod lifting device and the two limit holes in the X direction of the wave-breaking plate. The welding method of the enclosure welding type wave-breaking plate includes the following steps: first, the wave-breaking plate is placed on the push rod by a manipulator. The push rod has a lifting function under the action of the cylinder, and its D-shaped shape needs to be consistent with the shape of the limit hole of the wave-breaking plate to play the purpose of stopping rotation. Two steps are arranged on the push rod and cooperate with the upper and lower side holes of the limit hole to play the upper and lower limit purposes respectively; when the blank goes down, the push rod will rise vertically synchronously under the action of the cylinder to transport the wave-breaking plate into the blank, and when the position of the pitting plate is horizontally aligned with the position of the pitting welding inner wall of the left and right fuel tank blow molding molds, the mold is closed immediately. During the mold closing process, the fusion welding process of the pitting of the wave-breaking plate and the pitting welding inner wall of the fuel tank is completed. Before the left and right molds are completely closed, the push rod needs to be immediately retracted to the outside of the fuel tank body under the action of the cylinder.

2. The welded anti-wave plate of the conventional blow-molded oil tank according to claim 1, characterized in that: Four oil leakage holes are designed inside each reinforced rib panel; four equally divided long waist holes are designed on each pockmarked plate.

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