Pouring system for camshaft of internal combustion engine

Abstract

The invention discloses a pouring system for a cam shaft of an internal combustion engine, relates to the technical field of cam shaft pouring, and mainly aims at solving the internal defects that a cam shaft product produced by an existing pouring system is prone to shrinkage porosity and shrinkage cavity, low in matrix hardness and the like. The structure comprises a sprue, the top of the sprue is connected with a sprue cup, the bottom of the sprue is connected with the middle of a runner, two ends of the runner are respectively connected with one end of a straight runner, and camshaft cavities are arranged on two sides of the straight runner; four feeding heads are sequentially arranged on the straight runner, the lower parts of the side walls of the feeding heads are connected with the camshaft cavity through flow gates, and the sectional area ratio of the flow gates on the four feeding heads is set to be 1.1: 0.9: 0.9: 0.7 in the flowing direction of the liquid metal; and the feeding head and the two flow gates arranged on the feeding head jointly form a liquid supplementing cavity with a diamond-like structure. The invention provides a gating system for a camshaft of an internal combustion engine, which can complete the detection of a heavy fitting roller before installation, thereby avoiding the resource waste, saving the manpower loss and improving the detection efficiency.

Description

Technical Field

[0001] The present invention relates to the technical field of camshaft casting, and particularly relates to a casting system for an internal combustion engine camshaft. Background Art

[0002] As one of the key components of an internal combustion engine, the performance of the camshaft directly affects the overall performance and service life of the internal combustion engine. At present, the camshaft is mainly produced by casting using a casting system - the casting system is the general term for the channels through which liquid metal flows into the cavity in the mold, and its typical structure usually consists of a pouring cup (outer gate), a sprue, a sprue well, a runner, and an ingate, etc.

[0003] However, when the existing camshaft casting system is in use, it is difficult to ensure that the whole camshaft is filled simultaneously and solidifies uniformly, and there are often problems of insufficient feeding force, resulting in internal defects such as shrinkage porosity, shrinkage cavity, and uneven matrix hardness in the produced camshaft products. Moreover, most of the existing camshaft casting systems are two-piece casting systems per mold, and their production efficiency is not high. Summary of the Invention

[0004] The purpose of the present invention is to provide a casting system for an internal combustion engine camshaft, which can effectively reduce the probability of shrinkage porosity and shrinkage cavity in the camshaft, and at the same time can significantly improve the tensile strength, yield strength, and elongation rate of the camshaft.

[0005] The technical solution for the present invention to solve the above technical problems is: a casting system for an internal combustion engine camshaft, including a vertically arranged sprue, the top of the sprue is connected to a pouring cup, and the bottom is connected to the middle of a horizontally arranged runner. Both ends of the runner are respectively connected to one end of a horizontally arranged straight runner, and the two straight runners are arranged parallel to each other. On both sides of the extending direction of the straight runner, camshaft cavities parallel to the straight runner are horizontally arranged;

[0006] Four feeding risers are sequentially arranged on the straight runner. The lower part of the side wall of each feeding riser is connected to the camshaft cavities on both sides of the straight runner through a frustum-shaped ingate. The cross-sectional areas of the ingates on the four feeding risers are set to be 1.1:0.9:0.9:0.7 along the flow direction of the liquid metal; the feeding riser and the two ingates arranged thereon together form a liquid supplement cavity with a rhombus-like horizontal cross-section, and the two diagonals of the liquid supplement cavity are respectively communicated with the camshaft cavities on both sides of the straight runner.

[0007] As a further improvement of the present invention, the cross-sectional area of the runner: the cross-sectional area of the straight runner: the cross-sectional area of the ingate is 1.5 - 1.8:1 - 1.3:2.

[0008] As a further improvement of the present invention, the height of the feeding riser is more than twice the height from the parting surface of the camshaft cavity to the highest point of the camshaft cavity.

[0009] As a further improvement of the present invention, the inward inclination angle of the frustum-shaped inner gate is 25° - 35°.

[0010] As a further improvement of the present invention, the axial length of the inner gate is at least 5 mm.

[0011] As a further improvement of the present invention, the cross-sectional area of the channel of the inner gate is 200 mm 2 - 400 mm 2 .

[0012] As a further improvement of the present invention, the bottom of the sprue is connected to the middle part of the runner through a sprue well.

[0013] As a further improvement of the present invention, a filter is provided in the sprue well.

[0014] As a further improvement of the present invention, the upper surface of the end of the runner is connected to the lower surface of the end of the sprue.

[0015] As a further improvement of the present invention, a chilled iron liquid storage area is connected to the lower part of the end of the sprue far from the runner.

[0016] Beneficial effects

[0017] Compared with the prior art, the advantages of a gating system for an internal combustion engine camshaft of the present invention are as follows:

[0018] 1. In the gating system, the camshaft cavities all adopt multiple inner gates for liquid inlet. With the proportionate distribution of the cross-sectional areas of the inner gates, the purpose of simultaneous filling can be achieved. Moreover, by setting a supplementary liquid cavity with a rhomboid-like structure and combining with the heat preservation effect of the rhomboid-like supplementary liquid cavity, the temperature influence of the supplementary liquid cavity on the camshaft cavity can be avoided, so that the liquid metal in the camshaft cavity solidifies uniformly. In addition, by utilizing the heat preservation effect of the rhomboid-like supplementary liquid cavity and combining with the frustum-shaped inner gate, the supplementary liquid cavity can also have sufficient feeding force.

[0019] Therefore, the gating system can ensure the simultaneous filling and uniform solidification of the whole camshaft, and can provide sufficient feeding force, thereby effectively reducing the probability of shrinkage porosity and shrinkage cavity in the camshaft, and at the same time significantly improving the tensile strength, yield strength and elongation rate of the camshaft.

[0020] Through the following description and in combination with the drawings, the present invention will become clearer. These drawings are used to explain the embodiments of the present invention. Brief description of the drawings

[0021] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0022] Figure 1 Isometric view of the present invention;

[0023] Figure 2 Is a top-down cross-sectional view of the present invention.

[0024] Wherein: 1 - pouring cup; 2 - sprue; 21 - sprue well; 3 - runner; 4 - straight runner; 5 - riser; 6 - ingate; 7 - camshaft cavity; 8 - end overflow; 9 - chill iron liquid storage area. Detailed implementation manners

[0025] In order to make the purpose, technical solutions and advantages of the present invention clearer, the following further details the present invention in conjunction with the drawings. Obviously, the described embodiments are only some embodiments of the present invention, rather than all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts fall within the scope of protection of the present invention.

[0026] In the description of the present invention, it should be noted that unless otherwise clearly defined and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; of course, it can also be a mechanical connection or an electrical connection; in addition, it can also be directly connected, or indirectly connected through an intermediate medium, or the communication inside two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

[0027] Now refer to the drawings to describe the embodiments of the present invention.

[0028] Embodiment:

[0029] The specific implementation manner of the present invention is as Figure 1 , 2As shown in the figure, a gating system for an internal combustion engine camshaft includes a vertically arranged sprue 2. The top of the sprue 2 is connected to a pouring basin 1, and the bottom is connected to the middle of a horizontally arranged runner 3. Both ends of the runner 3 are respectively connected to one end of a horizontally arranged straight runner 4, and the two straight runners 4 are arranged parallel to each other. On both sides of the extending direction of the straight runner 4, camshaft cavities 7 parallel to the straight runner 4 are horizontally provided, that is, this gating system can produce four camshaft products in one pouring.

[0030] Among them, four risers 5 are sequentially arranged on each straight runner 4. The lower part of the side wall of the riser 5 is connected to the camshaft cavity 7 on both sides of the straight runner 4 through a frustum-shaped ingate 6. The cross-sectional area ratio of the ingates 6 on the four risers 5 of the same straight runner 4 is set to 1.1:0.9:0.9:0.7 along the flow direction of the liquid metal. In this embodiment, the riser 5 and the two ingates 6 arranged on it together form a liquid supplement cavity with a rhombus-like horizontal cross-section, and the two diagonals of the liquid supplement cavity are respectively communicated with the camshaft cavities 7 on both sides of the straight runner 4.

[0031] When using this gating system for camshaft pouring, the molten metal after smelting enters the gating system from the pouring basin 1, enters the runner 3 through the sprue 2 to split the molten metal, and then smoothly enters each straight runner 4; then, the molten metal enters the camshaft cavity 7 through the riser 5 and the ingate 6 to complete the entire filling process.

[0032] In this gating system, each camshaft is filled with liquid through four ingates 6. At the same time, based on the principle that the metal liquid fills the farthest point in the straight runner 4 first and the nearest point last, in order to ensure simultaneous filling as much as possible, the cross-sectional area of the proximal ingate 6 should be appropriately increased and the cross-sectional area of the distal ingate 6 should be reduced; therefore, the cross-sectional area ratio of the four ingates 6 is set to 1.1:0.9:0.9:0.7 along the flow direction of the liquid metal. Designed in this way, it can quickly complete the filling process on the basis of ensuring simultaneous filling, so that the temperature difference in the entire camshaft cavity is small and the uniformity of the product matrix is improved.

[0033] In addition, the shrinkage-compensating riser 5 and the two inner gates 6 of the pouring system together form a rhombus-shaped liquid replenishing cavity, and the two diagonals of the liquid replenishing cavity are respectively connected to the camshaft cavity 7 on both sides of the direct current channel 4. This design is because the solidification of the casting always follows the general principle of gradually solidifying from the low temperature zone to the high temperature zone. If the casting product is to have a dense structure, the temperature field of the entire casting product must be adjusted through the pouring riser so that it can gradually solidify from the lowest temperature zone to the high temperature zone. If the riser structure is too close to the product structure, a small high temperature zone will be formed near the product due to the influence of the riser temperature, and the product cannot achieve uniform solidification, increasing the risk of shrinkage cavities and shrinkage defects in the product body. Therefore, the rhombus-like structure of the filling cavity design of the casting system can make the filling cavity as far away from the edge of the camshaft cavity 7 as possible while completing the camshaft casting work, and because the rhombus-like structure of the filling cavity is conducive to heat preservation, it can prevent the camshaft cavity 7 from being affected by the liquid metal in the filling cavity at a position close to the filling cavity to form a small high-temperature zone, that is, a hot node, thereby making the liquid metal in the camshaft cavity 7 solidify evenly, and the hot nodes are concentrated in the filling cavity.

[0034] In addition, by utilizing the heat preservation effect of the rhombus-shaped liquid replenishment cavity, the liquid metal in the liquid replenishment cavity can be kept in liquid state for as long as possible. Combined with the prism-shaped inner gate, the liquid replenishment cavity of the casting system can have sufficient shrinkage compensation force, thereby improving the density of the product and further improving the product's main performance.

[0035] In summary, the casting system can ensure that the camshaft is filled and solidified uniformly at the same time, and can provide sufficient shrinkage compensation force, thereby effectively reducing the probability of shrinkage and shrinkage holes in the camshaft, and at the same time significantly improving the tensile strength, yield strength and elongation of the camshaft.

[0036] In the pouring system, the cross-sectional area of ​​the runner 3: the cross-sectional area of ​​the straight runner 4: the cross-sectional area of ​​the ingates 6 is 1.5-1.8:1-1.3:2, which is combined with a semi-open and semi-closed pouring system, which is conducive to reducing the speed of the molten metal and ensuring the filling time of the pouring. At the same time, the height of the shrinkage-feeding riser 5 is more than twice the height from the parting surface of the camshaft cavity 7 to the highest point of the camshaft cavity 7, which can further increase the shrinkage-feeding pressure. In addition, the inward inclination angle of the prism-shaped ingates 6 is 25°-35°, which is conducive to the formation of the shrinkage-feeding channel. If it is too large, it will affect the normal solidification of the camshaft, and if it is too small, the shrinkage-feeding capacity will be insufficient. In addition, the axial length of the ingates 6 is at least 5 mm. If it is too short, the liquid metal will be disordered after entering the camshaft cavity 7, resulting in defects such as pores and slag holes in the product casting. In this embodiment, the cross-sectional area of ​​the gate 6 is strongly related to the weight and structure of the product. The principle is that the gate 6 is not completely solidified when the product is completely solidified; therefore, the channel cross-sectional area of ​​the gate 6 in this embodiment is specifically set to 200mm 2 -400mm2 。

[0037] In this gating system, in order to prevent the slag in the liquid metal from affecting the product quality, the bottom of the sprue 2 is connected to the middle part of the runner 3 through a sprue well 21, and a filter is provided in the sprue well 21. Moreover, the reason why the ingate 6 is located at the lower part of the side wall of the riser 5 in this gating system is that the secondary slag in the liquid metal will float on the surface of the liquid metal. Therefore, when the liquid metal passes through the riser 5, the slag will quickly gather above the riser 5 due to the riser 5 being significantly higher than the ingate 6, while the clean liquid metal enters the camshaft cavity through the ingate 6 below. Thus, the riser 5 can perform secondary slag collection on the molten metal entering the camshaft cavity 7 before the filling process is completed, thereby reducing the risk of secondary slag in the molten metal entering the camshaft product. Therefore, this gating system with remarkable secondary slag removal ability also reduces the requirements for the melting process of the product, increases the adjustable range of the melting process, and further reduces the production cost.

[0038] In this embodiment, regarding the specific connection relationship between the runner 3 and the straight runner 4, the upper surface of the end of the runner 3 is connected to the lower surface of the end of the straight runner 4. At the same time, a chilled iron liquid storage area 9 is connected to the lower part of the end of the straight runner 4 far from the runner 3. The chilled iron liquid storage area 9 can store a part of the iron liquid that first passes through the runner and has a relatively large temperature drop, so that the molten metal entering the camshaft cavity 7 can always be maintained at a reasonable pouring temperature. Moreover, a tail-end overflow riser 8 is provided at one end of the camshaft cavity 7 far from the runner 3. The tail-end overflow riser 8 can store the iron liquid with too low a temperature that first enters the camshaft cavity 7 and the excess air in the camshaft cavity 7, improving the quality and qualification rate of the camshaft body.

[0039] The present invention has been described above in combination with the best embodiments, but the present invention is not limited to the disclosed embodiments above, and should cover various modifications and equivalent combinations made according to the essence of the present invention.

Claims

1. A gating system for an internal combustion engine camshaft, characterized in that, It includes a vertically arranged sprue (2), the top of the sprue (2) is connected to a pouring basin (1), and the bottom is connected to the middle of a horizontally arranged runner (3). Both ends of the runner (3) are respectively connected to one end of a horizontally arranged straight runner (4), and the two straight runners (4) are arranged parallel to each other. On both sides of the extending direction of the straight runner (4), camshaft cavities (7) parallel to the straight runner (4) are horizontally arranged. Four feeding risers (5) are successively arranged on the straight runner (4). Between the lower part of the side wall of the feeding riser (5) and the camshaft cavities (7) on both sides of the straight runner (4), they are all connected by frustum-shaped ingates (6). The cross-sectional area ratio of the ingates (6) on the four feeding risers (5) is set to 1.1:0.9:0.9:0.7 along the flow direction of the liquid metal. The feeding riser (5) and the two ingates (6) arranged thereon together form a liquid supplement cavity with a rhomboid-like horizontal cross-section, and the two diagonals of the liquid supplement cavity are respectively communicated with the camshaft cavities (7) on both sides of the straight runner (4).

2. The gating system for an internal combustion engine camshaft according to claim 1, characterized in that, The cross-sectional area of the runner (3): the cross-sectional area of the straight runner (4): the cross-sectional area of the ingate (6) is 1.5 - 1.8:1 - 1.3:

2.

3. The gating system for an internal combustion engine camshaft according to claim 1, characterized in that, The height of the feeding riser (5) is more than twice the height from the parting surface of the camshaft cavity (7) to the highest point of the camshaft cavity (7).

4. The gating system for an internal combustion engine camshaft according to claim 1 or 3, characterized in that, The inner inclination angle of the frustum-shaped ingate (6) is 25° - 35°.

5. The gating system for an internal combustion engine camshaft according to claim 1, characterized in that, The axial length of the ingate (6) is at least 5 mm.

6. The gating system for an internal combustion engine camshaft according to claim 1, characterized in that, The cross-sectional area of the gate (6) is 200mm 2 - 400mm 2 .

7. The gating system for an internal combustion engine camshaft according to claim 1, characterized in that, The bottom of the sprue (2) is connected to the middle of the runner (3) through a sprue well (21).

8. The gating system for an internal combustion engine camshaft according to claim 7, characterized in that, A filter is provided in the sprue well (21).

9. The gating system for an internal combustion engine camshaft according to claim 1, characterized in that, The upper surface of the end of the runner (3) is connected to the lower surface of the end of the straight runner (4).

10. The gating system for an internal combustion engine camshaft according to claim 1, characterized in that, A chill iron liquid storage area (9) is connected to the lower part of the end of the straight runner (4) far from the runner (3).

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