Forming process and forming processing system for automobile exhaust silencing bag shell

Abstract

The invention discloses an automobile exhaust silencing package shell forming process and a forming processing system thereof, blanking of an upper half shell material piece and a lower half shell material piece is carried out respectively, and the contours of the upper half shell material piece and the lower half shell material piece adopt two contour shapes respectively according to the forming sequence of multi-opening end structure molded surfaces of the upper half shell material piece and the lower half shell material piece; shell body molded surfaces, bevel end molded surfaces and multi-port end local molded surfaces of the two half shell structures are formed through a pre-forming mold, then the multi-port end molded surfaces are completely formed through a forming mold, and the pre-formed molded surfaces serve as positioning molded surfaces during complete forming; wherein the multi-port end, deviating to the side half shell, of the air inlet is firstly preformed into an outer side outline molded surface and then is completely molded into a multi-port end molded surface; and the multi-port end, deviating from the side half shell, of the air inlet is firstly pre-molded with an inner convex functional surface, and then is completely molded into a multi-port end molded surface. The problem that the exhaust silencing bag with the complex profile is poor in forming quality due to the adoption of a common process is solved.

Description

Technical Field

[0001] The invention relates to the technical field of automobile component molding, in particular to a molding process for an automobile exhaust silencer housing and a molding processing system thereof. Background Art

[0002] The exhaust silencer is an important component of the automobile exhaust system. The center line of its air inlet is generally set at an acute angle to the center line of the cylinder. The purpose is to enable the silencer to be arranged in a non-horizontal and non-vertical state, thereby effectively avoiding other structures of the vehicle and saving layout space. Its shell structure is used to form an internal functional cavity, which directly affects the silencer effect, so there are certain requirements for the precision and quality of the shell molding. The guide components for the inlet and outlet are all partial cone guides with arc-shaped transitions, and there is a multi-exhaust port structure at the exhaust end, which makes the shell surface structure precise and complex. It is difficult to control the direction of the material using conventional stamping and forming processes, resulting in poor quality of the final molded shell, affecting the silencer effect. Summary of the invention

[0003] Purpose of the invention: In order to overcome the deficiencies in the prior art, the present invention provides a shell molding process for an automobile exhaust silencer package and a molding processing system thereof, so as to solve the problem of poor molding quality of exhaust silencers with complex surfaces using common processes.

[0004] Technical solution: To achieve the above purpose, the present invention provides a vehicle exhaust silencer package shell molding process and a molding processing system thereof, wherein a stamping process is used to respectively perform profile molding of two half-shell structures, wherein the edges of the two half-shell structures are respectively formed with two flanging structures that can be buckled with each other, and the two half-shell structures are buckled with each other to form a silencer package shell, wherein one end of the silencer package shell provided with a skewed air inlet is a slanted end, and one end thereof provided with a plurality of parallel exhaust ports is a multi-port end; the specific molding process comprises the following steps:

[0005] Step I, blanking the upper half shell sheet and the lower half shell sheet respectively according to the preset sheet profile through a continuous blanking die, wherein the profiles of the upper half shell sheet and the lower half shell sheet respectively adopt two profile shapes according to the forming sequence of the multi-port end structural profiles of the two;

[0006] Step II, firstly, the shell body profile, the oblique end profile and the multi-port end partial profile of the two half-shell structures are respectively formed by a preforming die, and then the multi-port end profile is completely formed by a forming die, and the preformed profile is used as the positioning profile during the complete forming; wherein, the multi-port end of the half-shell on the side away from the air inlet is first preformed into an outer contour profile, and then completely formed into a multi-port end profile; the multi-port end of the half-shell on the side toward the air inlet is first preformed into an inner convex functional profile, and then completely formed into a multi-port end profile;

[0007] Step III, shaping the contour edge profile of the formed profile by means of a shaping die;

[0008] Step IV, cutting out the shape of the flanging structure according to a preset shearing contour by a shearing and flanging die, and completing the forming of the flanging structure by continuous stamping; wherein, the half shell body on the side biased toward the air inlet is formed with an inserted flanging structure, and the half shell body on the side away from the air inlet is formed with an outward buckled flanging structure.

[0009] Furthermore, the sheet of the half shell body facing away from the air inlet is cut into alternately arranged exhaust port half shell forming blocks a1 and transition curved surface forming blocks b corresponding to the multiple port ends, and the transition curved surface forming block b is protruding relative to the exhaust port half shell forming block a1.

[0010] Furthermore, the air inlet is biased towards the side half shell, and its sheet is cut into exhaust port half shell forming blocks a2 arranged in a continuous manner corresponding to the multiple port ends, and the exhaust port half shell forming blocks a2 are relatively larger than the exhaust port half shell forming blocks a1.

[0011] Furthermore, the outer contour surface is a complex surface in which a plurality of arc surfaces are connected by a gentle and smooth V-shaped surface transition; wherein the arc surface is a local surface constituting the exhaust port.

[0012] Furthermore, the inwardly convex functional profile is located between two adjacent exhaust ports, and its forming direction is opposite to the forming direction of the semi-arc profiles of the exhaust ports on both sides.

[0013] Furthermore, in step II, the oblique end profiles and the multi-end profiles of the two half-shell structures are formed into closed profiles; in step IV, circumferential shearing is adopted, and the annular waste edge is sheared into multiple sections by slitting shearing.

[0014] Furthermore, the multi-port end of the half shell body on the side biased by the air inlet is first preformed with the inwardly convex functional profile and a transition fold in line with its forming direction, and then formed into a multi-port end complete profile in one step.

[0015] Furthermore, the lower mold of the preforming mold is a male mold structure, including a protrusion structure adapted to the preforming surface, and a plurality of limiting sliders are arranged around the outside of the protrusion structure. Multiple limiting sliders are abutted against the edge of the sheet so that the sheet corresponds to the protrusion structure up and down.

[0016] Furthermore, the lower die of the molding die of the air inlet biased side half shell is a concave mold structure, including a molding surface positioning part and a molding part, and the molding part is provided with a positioning protrusion adapted to the inner convex functional molding surface.

[0017] Beneficial effects: The automobile exhaust silencer shell molding process and its molding processing system of the present invention adopt different multi-end complex surface molding steps according to the material flow direction of the two half-shell structures in the pre-molding, and correspondingly cut the molding sheets with different contours to ensure the balance of material thickness distribution after the shell is molded, as well as the splicing fit and tightness of the two half-shells after molding, so as to ensure the quality and function and achieve an effective and stable silencer effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is a schematic structural diagram of an embodiment of an automobile exhaust silencer package of the present invention;

[0019] Figure 2 It is a schematic diagram of the steps of forming the multi-port end of the half shell body on the side biased by the air inlet;

[0020] Figure 3 It is a schematic diagram of the steps for forming the multi-port end of the half shell body on the side away from the air inlet;

[0021] Figure 4 A schematic diagram showing the comparison of the profiles of the molding sheets of the two half-shell structures;

[0022] Figure 5 It is a schematic diagram of the preforming mold structure;

[0023] Figure 6 Schematic diagram of the molding die structure of the half shell on the side where the air inlet is biased

[0024] Figure 7 It is a schematic diagram of the cross-sectional structure at the air inlet and outlet when the two half-shell flange structures are buckled together. DETAILED DESCRIPTION

[0025] The present invention will be further described below in conjunction with the accompanying drawings.

[0026] As attached Figure 1-7The described automobile exhaust silencer package forming process and its forming processing system use a stamping process to respectively perform surface forming of two half-shell structures, the edges of the two half-shell structures are respectively formed with two kinds of flanging structures 11 that can be interlocked, the two half-shell structures are interlocked to form a silencer package shell, the silencer package shell is provided with an oblique air inlet at one end thereof as an oblique end 3, and is provided with a plurality of parallel exhaust ports at one end thereof as a multi-port end 4; the present scheme divides the silencer package shell into two half-shell structures by a dividing surface, so that the two half-shells are consistent in their surface structures except for the segregation direction of the oblique end relative to the shell body and the flanging structure 11, so as to facilitate the design and manufacture of the mold. Among them, the dividing surface is composed of two parts, one part is the dividing surface of the shell body, and the other part is the air inlet dividing surface. The shell body dividing surface is the plane where the center line of multiple exhaust ports and the center line of the shell body are located. The air inlet dividing surface is the plane where the center line of the air inlet is located, and the plane is parallel to the center line of the multiple exhaust ports. The two planes are connected at the intersection through a smooth curved surface transition to form the dividing surface.

[0027] The specific molding process includes the following steps:

[0028] Step I, blanking the upper half shell sheet and the lower half shell sheet respectively according to the preset sheet profile through a continuous blanking die, wherein the profiles of the upper half shell sheet and the lower half shell sheet respectively adopt two profile shapes according to the forming sequence of the multi-port end structural profiles of the two;

[0029] Step II, firstly, the shell body profile, the oblique end profile and the partial profile of the multi-port end of the two half-shell structures are formed by the preforming die, and then the multi-port end profile is completely formed by the forming die. The preformed profile is used as the positioning profile during the complete forming. Its purpose is to achieve balanced force on the material during the preforming process and ensure the forming accuracy of the shell structure during the complete forming. Since the inlet deflection angle is generally an acute angle, the oblique end profile is formed together with the shell body profile to reduce the forming steps and improve the forming efficiency. At the same time, the most complex multi-port end profile is completed separately to control the material flow distribution and ensure the accuracy and quality after forming. Since the multi-port end needs to be formed into a plurality of circular hole structure profiles arranged in a row, the corresponding half-shell structure is roughly a continuous corrugated structure. The multi-port end profile is formed in multiple times, which can avoid the material from being stretched in a short distance between the highest point and the lowest point in one forming. Large span misalignment, thereby avoiding the uneven thickness of the hole wall of the exhaust port after forming, ensures the forming quality.

[0030] Among them, the multi-port end of the half shell 2 on the side facing away from the air inlet is first preformed into an outer contour surface 5, and then fully formed into a multi-port end surface; the outer contour surface 5 is a complex surface in which multiple arc surfaces 52 are transitionally connected by a smooth V-shaped surface 51; wherein the arc surface 52 is a local surface constituting the exhaust port, and the smooth V-shaped surface 51 is the impact and stretching area when fully formed, which is used for stamping again to form a deep U-shaped transition surface between the two air outlets, and finally the inner convex functional surface 6 is formed to achieve complete forming, and the latter two forming dies both adopt a convex lower and concave upper mold form, and the lower mold uses the formed partial surface as the positioning surface to ensure the positioning accuracy of the forming.

[0031] The lower mold of the preforming mold is a male mold structure, including a convex block structure 7 adapted to the preforming profile, and a plurality of limit sliders are arranged around the outer side of the convex block structure 7, and the plurality of limit sliders are abutted against the edge of the sheet, so that the sheet corresponds to the convex block structure 7 up and down. The limit slider can be adjusted to move away or approach accordingly according to the shape and size of the cut sheet, and the abutting surface between the limit slider and the sheet is set as a cylindrical surface, which is convenient for multi-directional abutment and limiting requirements.

[0032] During the preforming process, the edge of the sheet contacts the upper die, and the middle part is against the lower convex die. Under the continuous pressure of the upper die, the edge of the sheet is pushed downward, and the sheet gradually fits with the lower convex mold surface from the middle area to the outside, and the flow direction of the material is roughly from the center to the surrounding. At the multi-port end position, the transition surface that needs to be formed into a deep U shape when fully formed is only formed into a gentle and smooth V-shaped surface 51, which is used to avoid excessive flow of materials toward the multi-port end, so that the thickness of the shell body part of the inlet biased side half shell 1 is relatively evenly distributed in the exhaust flow direction after forming, maintaining a relatively stable resonance, achieving stable interference with sound waves, and achieving the purpose of noise reduction and silencing.

[0033] As attached Figure 4 As shown, the air inlet is away from the side half shell 2, and its material sheet is cut into alternately arranged exhaust port half shell forming blocks a1 and transition curve forming blocks b corresponding to the multiple port ends. The transition curve forming block b is protruded relative to the exhaust port half shell forming block a1, so that during the pre-forming process, even if the block b is stretched to a certain extent, it will not affect the forming quality of the deep U-shaped transition curve, and sufficient stretching space is provided for the forming of the deep U-shaped transition curve. The two side walls of the deep U-shaped transition curve are part of the arc surface of the exhaust port on both sides, so the thickness distribution of the exhaust port hole wall can be further ensured to be uniform.

[0034] The multi-port end of the half shell 1 on the side of the air inlet is first preformed with an inward convex functional profile 6, and then fully formed into a multi-port end profile. The sheet is cut into a continuously arranged exhaust port half shell forming block a2 corresponding to the multi-port end, and the exhaust port half shell forming block a2 is relatively larger than the exhaust port half shell forming block a1. When only two exhaust ports are formed, the two convex vertices of the exhaust port half shell forming blocks a1 are relatively far away from the deflection outside, providing stretching material for the outer 1 / 4 arc surface of the exhaust port; while the convex vertices of the two exhaust port half shell forming blocks a2 are relatively close to the deflection and the central axis, and the transition from the two side edges to the convex vertices is a large arc contour, which can realize the exhaust port semi-circular arc surface forming to provide stretching material.

[0035] Since the inward convex functional profile 6 is located between two adjacent exhaust ports, and its forming direction is opposite to the forming direction of the semi-arc profiles of the exhaust ports on both sides, during the preforming of the half shell 2 on the side toward the air inlet, the inward convex functional profile 6 is formed synchronously, so that part of the material can flow toward the multi-port end, slowing down the flow of the material toward the boundary between the oblique port end profile and the shell body profile, thereby achieving a relatively balanced distribution of the shell body thickness in the exhaust gas flow direction after the half shell 2 on the side toward the air inlet is formed.

[0036] Preferably, the multi-port end of the half shell 1 on the side where the air inlet is biased is first preformed with the convex functional profile 6 and the transition fold 61 in the same direction as the forming direction thereof. At the same time, the parts formed into the exhaust ports on both sides are formed into two relatively gentle and smooth convex bumps 62 along the trend of the shell body forming, and then formed into a complete profile of the multi-port end in one step. The forming die of the half shell 1 on the side where the air inlet is biased, the lower die is a concave die structure, including a profile positioning part 8 and a forming part 9, and the forming part 9 is provided with a positioning protrusion 10 adapted to the convex functional profile 6. When fully formed, the convex functional profile 6 is fitted with the positioning protrusion 10, and the transition fold is abutted with the contour edge of the lower die, so as to achieve precise positioning, thereby ensuring the one-time forming accuracy of the arc profile of the exhaust port. In addition, the convex functional profile helps to achieve noise reduction and silencing through the reverse interference of sound waves, so it is formed separately to ensure that its forming is not affected by the forming of the surrounding profiles.

[0037] Step III, shaping the contour edge profile of the formed profile through a shaping die; mainly processing the rounded profile along the crease position of the flanging to facilitate high-quality forming of the flanging structure.

[0038] Step IV, cutting out the shape of the flanging structure according to the preset shearing contour by a shearing and flanging die, and completing the molding of the flanging structure by continuous stamping; wherein, the oblique end profiles and multi-end profiles of the two half-shell structures are both molded into closed profiles, and then the closed portion is cut off by trimming, which can ensure the molding quality of the port portion of the air inlet and outlet, and the circumferential one-time shearing is used to ensure the quality of the flanging section, avoiding the problem of loose buckling and affecting the silencing effect, and the annular waste edge is sheared into multiple sections by slitting shearing, which is convenient for the recycling of the annular waste edge; wherein, the half-shell 1 on the side biased by the air inlet is molded with an inserted flanging structure 12, and the half-shell 2 on the side away from the air inlet is molded with an external buckle flanging structure 13. Figure 7 As shown, the inserted flange structure is a flange tangent to the edge of the profile, while the outer buckle flange structure and the flange structure bent outward relative to the profile edge by a distance of the thickness of the sheet, so that the inserted flange structure is just inserted into the outer buckle flange structure, and the profile edges of the two half shells are ensured to coincide with each other, so as to be correctly spliced ​​into a complete sound-absorbing package shell.

[0039] The shearing and flanging die comprises a trimming die and a flanging die, the trimming die is provided with a trimming upper die and a trimming lower die which fit in with each other, the trimming lower die is provided with an embedding groove which matches with the trimming upper die; the flanging die is provided with a flanging die and a flanging pressing plate, the flanging die is lifted and lowered in the embedding groove, the bottom of the flanging die is elastically connected with the bottom of the embedding groove; the flanging die is provided with a flanging structure support block and a profile structure support block, the flanging pressing plate is aligned with the profile structure support block up and down, and the flanging pressing plate extends downward from the lower edge of the trimming upper die The end face cooperates with the flanging die; a movable groove is provided in the middle of the flanging structure support block, and the profile structure support block is lifted and lowered in the movable groove, and the profile structure support block is elastically connected to the bottom of the movable groove; when the upper end face of the profile structure support block is flush with the upper end face of the flanging structure support block, the profile structure support block and the flanging structure support block are locked by a locking pin structure to keep the relative position fixed; a contact switch is provided at the lower limit position of the flanging die, and the contact switch control signal transmission is connected to the locking pin structure for touch-controlled unlocking.

[0040] Among them, the profile structure support block has a groove adapted to the shell profile for shearing positioning. In the initial state, the profile structure support block, the flanging structure support block and the upper end surface of the trimming lower die are flush. When the trimming upper die contacts the sheet, it and the flanging structure support block clamp the part other than the waste edge, thereby driving the part to move downward, and causing dislocation shearing with the waste edge restricted by the trimming lower die to achieve the purpose of trimming. At the same time, multiple slitting tools are arranged around the trimming upper die at the corners corresponding to the annular waste edge. When the upper die drops to a certain height, the slitting tool cooperates with the upper end surface of the trimming lower die to shear the annular waste edge into multiple segments. At the same time, the cooperation between the slitting tool and the trimming lower die can also limit the downward limit position of the trimming upper die, and at the same time trigger the movement of the flanging pressure plate relative to the lower end surface of the trimming upper die. By pushing down the flanging pressure plate, the scrap sheet and the flanging die will move away from the trimming upper die, thereby releasing the clamping of the flanging part. At the same time, the flanging pressure plate and the profile structure support block clamp the profile part together to protect the profile part. When the flanging die moves down to the limit position, the lock pin is triggered to unlock, and the flanging pressure plate presses the profile structure part of the sheet into the movable groove, so that the flanging part is bent relative to the profile part to form a flanging structure. The trimming and flanging actions are completed by one stamping from top to bottom. During the process, the position of the profile part will not change, thereby ensuring the position accuracy of the flanging crease forming, and at the same time improving the overall forming efficiency.

[0041] The above description is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the above principles of the present invention. These improvements and modifications are also considered to be within the scope of protection of the present invention.

Claims

1. A process for forming a shell of an automobile exhaust silencer package, characterized in that: The two half-shell structures are respectively formed by a stamping process, and the edges of the two half-shell structures are respectively formed with two flange structures that can be interlocked. The two half-shell structures are interlocked to form a silencer package shell, and the end of the silencer package shell provided with a skewed air inlet is a slanted end (3), and the end of the silencer package shell provided with a plurality of parallel exhaust ports is a multi-port end (4). The specific forming process comprises the following steps: Step I, blanking the upper half shell sheet and the lower half shell sheet respectively according to the preset sheet profile through a continuous blanking die, wherein the profiles of the upper half shell sheet and the lower half shell sheet respectively adopt two profile shapes according to the forming sequence of the multi-port end structural profiles of the two; Step II, firstly, the shell body profile, the oblique end profile and the multi-port end partial profile of the two half-shell structures are respectively formed by a preforming die, and then the multi-port end profile is completely formed by a forming die, and the preformed profile is used as the positioning profile during the complete forming; wherein, the multi-port end of the half-shell (2) on the side away from the air inlet is first preformed into an outer contour profile (5), and then completely formed into a multi-port end profile; the multi-port end of the half-shell (1) on the side toward the air inlet is first preformed into an inner convex functional profile (6), and then completely formed into a multi-port end profile; Step III, shaping the contour edge profile of the formed profile by means of a shaping die; Step IV, cutting out the shape of the flanging structure according to a preset cutting contour by a shearing and flanging die, and completing the forming of the flanging structure by continuous stamping; wherein the half shell (1) on the side biased toward the air inlet is formed with an inserted flanging structure, and the half shell (2) on the side away from the air inlet is formed with an outward buckled flanging structure.

2. The automobile exhaust silencer shell forming process according to claim 1 is characterized in that: The half shell (2) on the side facing away from the air inlet has a sheet cut out to form alternately arranged exhaust half shell forming blocks a1 and transition curved surface forming blocks b corresponding to the multiple openings, and the transition curved surface forming block b is arranged to protrude relative to the exhaust half shell forming block a1.

3. The automobile exhaust silencer shell forming process according to claim 2 is characterized in that: The air inlet biased side half shell (1) has a sheet cut out corresponding to the multiple port ends to form exhaust port half shell forming blocks a2 arranged in a continuous pattern, and the exhaust port half shell forming blocks a2 are relatively larger than the exhaust port half shell forming blocks a1.

4. The automobile exhaust silencer shell forming process according to claim 3 is characterized in that: The outer contour profile (5) is a complex profile in which a plurality of arc surfaces (52) are transitionally connected through a smooth V-shaped curved surface (51); wherein the arc curved surface (52) is a local profile constituting an exhaust port.

5. The process for forming the shell of an automobile exhaust muffler package according to claim 4 is characterized in that The inwardly convex functional profile (6) is located between two adjacent exhaust ports, and its forming direction is opposite to the forming direction of the semi-arc profiles of the exhaust ports on both sides.

6. The automobile exhaust silencer shell forming process according to claim 5 is characterized in that: In step II, the oblique end profiles and the multi-end profiles of the two half-shell structures are formed into closed profiles; in step IV, circumferential shearing is adopted, and the annular waste edge is sheared into multiple sections by slitting shearing.

7. The automobile exhaust silencer shell forming process according to claim 6 is characterized in that: The multi-port end of the half shell (1) on the air inlet biased side is first preformed with the inwardly convex functional profile (6) and a transition fold in the same direction as its forming, and then formed into a complete profile of the multi-port end in one step.

8. A molding processing system for automobile exhaust silencer shell molding process according to any one of claims 1 to 6, characterized in that: The lower die of the preforming die is a male die structure, comprising a convex block structure (7) adapted to the preforming surface, a plurality of limit sliders are arranged around the outer side of the convex block structure (7), and a plurality of the limit sliders are abutted against the edge of the sheet material, so that the sheet material corresponds to the convex block structure (7) up and down.

9. The molding processing system of the automobile exhaust silencer shell molding process according to claim 8 is characterized in that: The molding die of the air inlet biased side half shell (1) has a lower mold of a concave mold structure, including a molding surface positioning part (8) and a molding part (9), and the molding part (9) is provided with a positioning protrusion (10) adapted to the inner convex functional molding surface (6).

Images