Casting mold for automobile exhaust pipe

Abstract

The utility model discloses an automobile exhaust pipe casting mold, and belongs to the technical field of casting equipment. Comprising an inner sand mold, a forming cavity is formed in the inner sand mold, a first upper sand mold, a second upper sand mold and a third upper sand mold are located in an upper mold in a clamped state to form an upper inner sand mold, a first lower sand mold, a second lower sand mold and a third lower sand mold are located in a lower mold in a clamped state to form a lower inner sand mold, and a head sand block, a middle sand block and a tail sand block are arranged between the head sand block and the middle sand block. An exhaust structure is arranged between the upper inner sand mold, the lower inner sand mold and the tailing block and located at the bend position of the forming cavity, a plurality of air holes are formed in the bend position of the pouring cavity, the evenly-formed air holes are connected with a connecting hole channel, the connecting hole channel is connected with an exhaust pipe, and the connecting hole channel is arranged to be in an arc shape with the same radian as the bend. And air at the bend can be exhausted as much as possible, air holes are prevented from being formed in dead corners of the bend, air holes are formed in poured steel, and the firmness degree of the steel is reduced.

Description

Technical Field

[0001] The present application relates to the technical field of casting equipment, and more specifically, to a casting mold for an automobile exhaust pipe. Background Art

[0002] With the rapid development of my country's automobile industry, my country has the ability to independently develop and produce automobiles. The exhaust pipe is an important component in the automobile. The automobile exhaust pipe is also called the automobile exhaust pipe hose. It is installed in the exhaust pipe between the engine exhaust branch pipe and the muffler, making the entire exhaust system flexibly connected, thereby reducing vibration and noise, facilitating installation and extending the life of the exhaust muffler system. It is mainly used in light vehicles, micro vehicles and buses. Its structure is a double-layer corrugated pipe covered with a steel wire mesh sleeve, and the straight edge sections at both ends are covered with a clamping ring. In order to achieve a better muffler effect, the bellows can be equipped with a telescopic joint or a mesh sleeve.

[0003] Existing automobile exhaust pipe casting molds, such as an exhaust pipe casting mold proposed by Chinese patent number CN208929140U, include an upper mold plate and a lower mold plate, which are arranged layer by layer in sequence, one side of the upper mold plate is provided with an upper mold cavity, one side of the lower mold plate is provided with a lower mold cavity matched with the upper mold cavity, a first sand mold block and a second sand mold block for molding the internal pipe of the exhaust pipe are installed in the lower mold cavity, the first sand mold block and the second sand mold block are plugged and matched, and a third sand mold block and a fourth sand mold block are also arranged in the lower mold cavity, and the third sand mold block and the fourth sand mold block wrap part of the second sand mold block. The advantage of this exhaust pipe casting mold is that it is dedicated to molding a certain exhaust pipe.

[0004] Due to the special shape of automobile exhaust pipes, there are many bends and the length runs through the bottom of the car, which makes casting difficult. Dead corners are easily formed in the bend area of ​​the inner runner during casting. Due to the gas pressure in the cavity, the gasified residues accumulate in the dead corners to form pores. In addition, the automobile exhaust pipe is made of stainless steel, which contains a certain amount of hydrogen. These hydrogen elements will form bubbles in the metal liquid at high temperatures, which may cause uneven density of the steel and affect the strength and toughness of the steel. The generation and diffusion of bubbles inside the steel will cause cracks on the surface of the steel, affecting the appearance and quality of the steel. If the gas in the metal liquid is not discharged during the casting process, pores will be formed inside the steel, reducing the strength of the steel. In order to ensure the thickness, bending smoothness, quality and performance of stainless steel parts, we propose a casting mold for automobile exhaust pipes. Utility Model Content

[0005] 1. Technical issues to be solved

[0006] The purpose of the present application is to provide a casting mold for an automobile exhaust pipe to solve the problems raised in the above background technology.

[0007] 2. Technical solution

[0008] A casting mold for an automobile exhaust pipe, comprising:

[0009] An upper mold and a lower mold, wherein the lower mold is plugged and engaged at the bottom end of the upper mold.

[0010] An inner sand mold is arranged inside the upper mold and the lower mold, and a molding cavity for molten iron pouring is opened inside the inner sand mold. The inner sand mold consists of an upper sand mold one, an upper sand mold two, an upper sand mold three, a lower sand mold one, a lower sand mold two, a lower sand mold three, a head sand block, a middle sand block and a tailing sand block. The upper sand mold one, the upper sand mold two and the upper sand mold three are located inside the upper mold in a clamping state to form an upper inner sand mold. The lower sand mold one, the lower sand mold two and the lower sand mold three are located inside the lower mold in a clamping state to form a lower inner sand mold. The head sand block, the middle sand block and the tailing sand block are arranged in the middle of the two, and an exhaust structure is arranged between the upper and lower inner sand molds and the tailing sand block. The exhaust structure is located at the bend position of the molding cavity and can discharge the gas at the bend position of the molding cavity.

[0011] As an optional solution to the technical solution of the present application document, the exhaust structure includes two air holes arranged on the three sides of the lower sand mold, one end of the two air holes is connected to the tail end of the molding cavity, and the other end of the two air holes is connected to the connecting channel two.

[0012] As an optional solution to the technical solution of the present application document, the exhaust structure also includes two air holes one arranged on the three sides of the upper sand mold, the two air holes one are evenly arranged, one end of the two air holes one is connected to the tail end of the molding cavity, and the other end of the two air holes one is connected to the connecting channel one.

[0013] As an optional solution of the technical solution of the present application document, the bottom end of the connecting channel 1 is connected to the air hole 1, and the connecting channel 1 and the connecting channel 2 together constitute an arc-shaped exhaust channel, and the curvature of the arc-shaped exhaust channel is the same as the curvature of the molding cavity bend.

[0014] As an optional solution to the technical solution of the present application document, the exhaust structure also includes an exhaust port fixedly opened inside the upper mold, the bottom end of the exhaust port is connected to a connecting channel, and the top end of the exhaust port is hinged with a dust cover for closing it.

[0015] As an optional solution of the technical solution of the present application document, the bottom ends of the upper sand mold 1, the upper sand mold 2 and the upper sand mold 3 are all fixedly provided with a clamping plate, and the top ends of the lower sand mold 1, the lower sand mold 2 and the lower sand mold 3 are provided with a plate groove, and the clamping plate is engaged and connected with the plate groove;

[0016] A plurality of round blocks are evenly fixed on the same end of the upper sand mold 1 and the upper sand mold 2, and a plurality of round grooves are evenly arranged on the other end of the upper sand mold 2 and the upper sand mold 3, and the round blocks are engaged and connected with the round grooves;

[0017] A clamping groove is fixed on the same side of the head sand block and the middle sand block, and a circular plate is fixed on the other side of the middle sand block and the tail sand block, and the circular plate is clamped and connected with the clamping groove.

[0018] As an optional solution of the technical solution of the present application document, the outer sides of the upper mold and the lower mold are jointly combined with a casting cavity, and the bottom end of the casting cavity is arranged in an inclined shape to facilitate the casting of molten iron;

[0019] A plurality of overflow holes are symmetrically arranged on the side of the casting cavity, and the overflow holes are arranged in a curved state to prevent the hot air from being discharged and burning the workers.

[0020] 3. Beneficial effects

[0021] Compared with the prior art, the advantages of this application are:

[0022] By arranging a plurality of air holes at the bend of the casting cavity, the evenly arranged air holes are connected to the connecting channels, the connecting channels are connected to the exhaust pipe, and the connecting channels are arranged to be in an arc shape with the same arc as the bend, the air at the bend can be completely discharged, avoiding the formation of air holes at the dead corners of the bend, causing air holes to be formed inside the cast steel, thereby reducing the strength of the steel. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 The figure is a schematic diagram of the overall structure of a casting mold for an automobile exhaust pipe;

[0024] Figure 2 The figure is a schematic side cross-sectional view of the overall structure of a casting mold for an automobile exhaust pipe;

[0025] Figure 3 The exploded schematic diagram of an upper mold, a lower mold and an inner sand mold of a casting mold for an automobile exhaust pipe;

[0026] Figure 4 It is a cross-sectional schematic diagram of the upper sand mold 3 and the lower sand mold 3 of a casting mold for an automobile exhaust pipe;

[0027] Explanation of numbers in the figure: 1. Upper mold; 11. Upper sand mold one; 12. Upper sand mold two; 13. Upper sand mold three; 131. Connecting channel one; 132. Air hole one; 14. Dust cover; 15. Exhaust port; 2. Lower mold; 21. Lower sand mold one; 22. Lower sand mold two; 23. Lower sand mold three; 231. Connecting channel two; 232. Air hole two; 3. Inner sand mold; 31. Head sand block; 32. Middle sand block; 33. Tail sand block; 4. Casting cavity; 5. Overflow hole; 6. Molding cavity. DETAILED DESCRIPTION

[0028] refer to Figure 1-4 , a technical solution proposed.

[0029] like Figure 1 As shown, the right end of the exhaust pipe body is an air connection head connected to the engine, and the left end is an air outlet head for exhaust. The exhaust pipe body is a curved shape set according to the wiring direction of the automobile chassis. The casting mold of the exhaust pipe consists of an upper mold 1 and a lower mold 2. The upper mold 1 and the lower mold 2 are provided with an internal cavity inside, and an inner sand mold 3 is provided inside the cavity. The inner sand mold 3 is composed of an upper and lower part. A molding cavity 6 for molding the internal pipeline of the exhaust pipe is installed inside the inner sand mold 3. The casting process is a casting molding process of an exhaust pipe casting mold of Chinese patent number CN208929140U. The upper mold and the lower mold are matched, and the metal liquid is injected into the mold. After waiting for the metal liquid to cool and form, the molding of the exhaust pipe is completed. In this application, the upper mold 1 and the lower mold 2 contact surfaces can be snapped and fixed, and the same side is fixedly connected with the casting cavity 4. The bottom of the casting cavity 4 is inclined to facilitate the injection of molten metal. Overflow holes 5 are arranged on both sides of the casting cavity 4. One end of the overflow hole 5 is arranged at the inner sand mold 3, and the other end of the overflow hole 5 extends out of the mold, and the length is slightly longer than the length of the casting cavity 4. The size of the overflow hole 5 is a through hole state with a large outside and a small inside. When pouring molten iron into the casting cavity 4, the heated air in the molding cavity 6 can overflow from the overflow hole 5. The overflow hole 5 is set in a curved state, which increases the difficulty of molten iron overflowing and cools the heated air ejected to avoid accidental injury to the staff. An overflow prevention cup can also be set at the bottom of the overflow hole 5, which can not only discharge the dirty molten metal to play the role of exhaust scum, but also prevent the formation of pores at the root of the overflow hole 5;

[0030] like Figure 2 , Figure 3 and Figure 4 As shown, the inner sand mold 3 arranged on the inner side of the upper mold 1 is composed of an upper sand mold 1 11, an upper sand mold 2 12 and an upper sand mold 3 13. A round block is fixedly arranged on one side of the upper sand mold 11, and the round block is engaged with a round groove on one side of the upper sand mold 2 12. A round block is fixedly arranged on the other side of the upper sand mold 2 12, and the round block on one side of the upper sand mold 2 12 is engaged with a round groove on one side of the upper sand mold 3 13. The upper sand mold 1 11, the upper sand mold 2 12 and the upper sand mold 3 13 together constitute the upper part of the inner sand mold 3;

[0031] like Figure 2 , Figure 3 and Figure 4 As shown, the inner sand mold 3 arranged on the inner side of the lower mold 2 is composed of a lower sand mold 1 21, a lower sand mold 2 22 and a lower sand mold 3 23. A round block is fixedly arranged on one side of the lower sand mold 1 21, and the round block is engaged with a round groove on one side of the lower sand mold 22. A round block is fixedly arranged on the other side of the lower sand mold 22, and the round block on one side of the lower sand mold 22 is engaged with a round groove on one side of the lower sand mold 3 23. The lower sand mold 1 21, the lower sand mold 2 22 and the lower sand mold 3 23 together constitute the lower part of the inner sand mold 3;

[0032] A clamping plate is fixedly arranged at the bottom of the upper part of the inner sand mold 3, and the clamping plate is embedded in the inner side of the clamping slot. The clamping slot is arranged at the top of the lower part of the inner sand mold 3. The upper and lower parts of the inner sand mold 3 are clamped and connected, and the staff can install and assemble it simply and quickly.

[0033] like Figure 2 , Figure 3 and Figure 4 As shown, the upper sand mold 11 and the lower sand mold 1 21 together constitute the front end of the automobile exhaust pipe casting, the upper sand mold 2 12 and the lower sand mold 2 22 together constitute the middle end of the automobile exhaust pipe casting, the front end and the middle end casting parts are the lateral parts of the exhaust pipe, the upper sand mold 3 13 and the lower sand mold 3 23 together constitute the bent tail end of the automobile exhaust pipe casting, and the bent tail end is fixedly provided with a tailing sand block 33 with the same size as the exhaust hole inside the automobile exhaust pipe, and its size can be limited when the sand mold is made according to needs, suitable for different exhaust requirements, a circular plate is provided at the other end of the tailing sand block 33, and the other end of the circular plate is embedded in the slot, the slot is set at one end of the middle sand block 32, and the other end of the middle sand block 32 is fixedly provided with a circular plate, and the other end of the circular plate is connected with the slot, and the slot is set at one end of the head sand block 31, and the head sand block 31 and the middle sand block 32 are in the same straight line, so that the staff can accurately engage and limit them;

[0034] The holes and grooves between the upper sand mold 3 13, the lower sand mold 3 23 and the tailing sand block 33, the holes and grooves between the lower sand mold 1 21, the lower sand mold 22 and the lower sand mold 3 23, and the holes and grooves between the upper sand mold 1 11, the lower sand mold 1 21 and the head sand block 31 together constitute the molding cavity 6. The molten iron is cooled and solidified in the molding cavity 6 to form the required automobile exhaust pipe. Two air holes 132 are arranged at the top bend of the upper sand mold 3 13. One end of the connecting hole 231 is in contact with the molding cavity 6, and the other end of the air hole 132 is in contact with the air hole 1 132 is fitted, and the air at the bend can be discharged from the air hole 132 into the connecting channel 131. A second air hole 232 is arranged at the bend position of the lower sand mold 3 23. One end of the second air hole 232 is fitted with the molding cavity 6, and the other end of the second air hole 232 is fitted with the connecting channel 231. The air at the bend of the lower sand mold 3 23 can be discharged from the air hole 232 into the connecting channel 231. The connecting channel 131 and the connecting channel 231 together constitute an arc-shaped exhaust channel. The connecting channel 131 and the connecting channel 231 The second connection channel 231 is evenly distributed on the box wall or bottom plate, and the total area of ​​the first connection channel 131, the second connection channel 231 and the plurality of overflow holes 5 used for the initial stage only accounts for 3% to 5% of the area of ​​the box wall or bottom plate, reducing the risk of drilling and avoiding too small or too few settings, thereby reducing the exhaust effect of the sand box. The arc-shaped exhaust channel has the same arc as the car exhaust pipe bend, and can discharge the various gases precipitated from the sand mold cavity, the sand core and the molten metal, reduce the gas pressure in the mold cavity during filling, and improve the filling of the molten metal. Molding capacity, the top of the connecting channel 131 is connected with the bottom of the exhaust port 15. The exhaust port 15 can be provided with a tail air outlet, an air outlet needle, an air outlet sheet, and an exhaust filter. The main purpose is to exhaust. The top of the exhaust port 15 is hingedly connected with a dust cover 14. After the pouring is completed, the dust cover 14 can be flipped over to close the exhaust port 15 to avoid high temperature and high humidity environment and the sand mold getting wet after long-term storage, resulting in poor exhaust. There is a risk of causing safety accidents during pouring, which may cause choking at the least and "drilling steel" and splashing of molten metal at the worst.

[0035] Before casting the automobile exhaust pipe, first place the lower sand mold 3 23 inside the flat lower mold 2, then place the upper sand mold 3 13 on the top of the lower sand mold 3 23 fixed with the tailing sand block 33 to form the tail end of the automobile exhaust pipe casting, then place the lower sand mold 2 22, the lower sand mold 3 23 and the lower sand mold 1 21 in sequence to form the middle end of the automobile exhaust pipe casting, and finally place the upper sand mold 2 12, the upper sand mold 3 13 and the upper sand mold 1 11 in sequence, which are fixed and locked with each other to facilitate the workers to operate quickly, and at the same time, the combined interior also forms a molding cavity 6 for the final molding of the exhaust pipe, and the molding cavity 6 is evenly provided with air holes 2 at the bend at the tail end. 32 and pore 1 132, pore 1 132 and pore 2 232 are evenly arranged on one side of the arc-shaped exhaust channel formed by the connecting channel 131 and the lower sand mold 21. Then the upper mold 1 is covered on the top of the lower mold 2, and the upper mold 1 and the lower mold 2 are engaged with each other. At this time, the top of the arc-shaped exhaust channel is connected with the exhaust port 15, and the top of the exhaust port 15 is hingedly connected with a dust cover 14. When the molten iron pouring operation is not performed, it is closed. Before the molten iron pouring operation is performed, it is opened to facilitate gas discharge. Finally, molten iron is poured into the molding cavity 6. The high-temperature molten iron makes the molding cavity 6 in a high-temperature and high-pressure state, and the air is squeezed and can be quickly discharged.

[0036] Although examples of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A casting mold for an automobile exhaust pipe, comprising an upper mold (1) and a lower mold (2), wherein the lower mold (2) is plugged into the bottom end of the upper mold (1); characterized in that: An inner sand mold (3) is arranged inside the upper mold (1) and the lower mold (2), and a molding cavity (6) for molten iron pouring is opened inside the inner sand mold (3). The inner sand mold (3) is composed of an upper sand mold 1 (11), an upper sand mold 2 (12), an upper sand mold 3 (13), a lower sand mold 1 (21), a lower sand mold 2 (22), a lower sand mold 3 (23), a head sand block (31), a middle sand block (32) and a tail sand block (33). The upper sand mold 1 (11), the upper sand mold 2 (12) and the upper sand mold 3 (13) are in a locked state. The upper mold (1) is provided inside the upper mold to form an upper inner sand mold (3); the lower sand mold one (21), the lower sand mold two (22) and the lower sand mold three (23) are located inside the lower mold (2) in a clamped state to form a lower inner sand mold (3); the head sand block (31), the middle sand block (32) and the tailing sand block (33) are arranged in the middle of the two, and an exhaust structure is provided between the upper and lower inner sand molds (3) and the tailing sand block (33); the exhaust structure is located at the bend position of the molding cavity (6) and can exhaust the gas at the bend position of the molding cavity (6).

2. The automobile exhaust pipe casting mold according to claim 1, characterized in that: The exhaust structure comprises a second air hole (232) arranged on the side of the lower sand mold (23), one end of the second air hole (232) is connected to the rear end of the molding cavity (6), and the other end of the second air hole (232) is connected to the second connecting channel (231).

3. The automobile exhaust pipe casting mold according to claim 1, characterized in that: The exhaust structure also includes two air holes (132) arranged on the sides of the upper sand mold (13), the two air holes (132) are evenly arranged, one end of the two air holes (132) is connected to the rear end of the molding cavity (6), and the other end of the two air holes (132) is connected to the connecting channel (131).

4. The automobile exhaust pipe casting mold according to claim 3, characterized in that: The bottom end of the connecting channel 1 (131) is connected to the air hole 1 (132), and the connecting channel 1 (131) and the connecting channel 2 (231) together form an arc-shaped exhaust channel, and the curvature of the arc-shaped exhaust channel is the same as the curvature of the bend of the molding cavity (6).

5. The automobile exhaust pipe casting mold according to claim 1, characterized in that: The exhaust structure also includes an exhaust port (15) fixedly opened inside the upper mold (1), the bottom end of the exhaust port (15) is connected to the connecting channel 1 (131), and the top end of the exhaust port (15) is hinged with a dust cover (14) for closing it.

6. The automobile exhaust pipe casting mold according to claim 1, characterized in that: The upper sand mold 1 (11), the upper sand mold 2 (12) and the upper sand mold 3 (13) are all fixedly provided with a clamping plate at their bottom ends, and the lower sand mold 1 (21), the lower sand mold 2 (22) and the lower sand mold 3 (23) are provided with a plate groove at their top ends, and the clamping plate is engaged and connected with the plate groove; A plurality of round blocks are evenly fixed on the same end of the upper sand mold 1 (11) and the upper sand mold 2 (12), and a plurality of round grooves are evenly arranged on the other end of the upper sand mold 2 (12) and the upper sand mold 3 (13), and the round blocks are engaged and connected with the round grooves; The head sand block (31) and the middle sand block (32) are both fixed with a slot on the same side, and the middle sand block (32) and the tail sand block (33) are both fixed with a circular plate on the other side, and the circular plate is engaged with the slot.

7. The automobile exhaust pipe casting mold according to claim 4, characterized in that: The upper mold (1) and the lower mold (2) are combined on their outer sides to form a casting cavity (4), and the bottom end of the casting cavity (4) is arranged in an inclined shape to facilitate the casting of molten iron; The side of the casting cavity (4) is symmetrically provided with a plurality of overflow holes (5), and the overflow holes (5) are arranged in a curved state, so as to prevent the discharge of hot air from burning workers.

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