A casting forming device for automobile piston production

Abstract

The application discloses a casting forming device for automobile piston production, which comprises a bottom die, side dies, an inner die and an exhaust pipe; the bottom die and the inner die are arranged between the two side dies and are used for forming a piston casting space; the bottom die comprises a plunger and a pouring opening, and the pouring opening is used for inputting aluminum liquid; the inner die comprises a riser; the exhaust pipe comprises a second spring, an overflow bin, an isolation bin and a pressure relief valve, and the exhaust pipe is matched with the plunger and is used for eliminating the excess edge and corner materials at the riser and the pouring opening. The application can effectively reduce the edge and corner materials at the riser and the pouring opening in the piston forming process, improve the casting completion degree of the piston, and further simplify the demolding process of the piston and improve the demolding efficiency.

Description

Technical Field

[0001] This invention relates to the field of automotive engine component casting technology, specifically a casting forming apparatus for automotive piston production. Background Technology

[0002] Low-pressure casting, a casting process used to manufacture high-quality pistons, is characterized by using a low pressure of 0.01-0.05 MPa to force molten metal from a sealed, insulated furnace into a mold cavity. Under pressure, the molten metal slowly fills and solidifies, ultimately forming a casting that meets the required specifications. Low-pressure casting offers advantages such as high quality, high precision, high material utilization, and applicability to complex structures, and is widely used in the manufacturing of internal combustion engines for automobiles, motorcycles, and ships.

[0003] Compared to traditional casting and high-pressure casting, existing low-pressure casting technology leaves less residue at the risers and gates of the mold. However, residual scrap material still adheres to the surface of the casting. This not only increases the surface treatment steps but also reduces the integrity of the casting. These problems increase processing costs and affect production efficiency.

[0004] Secondly, in low-pressure casting, the mold needs to maintain a certain pressure within the mold cavity before the casting solidifies, until the casting is completely solidified. This characteristic leads to low efficiency in low-pressure casting.

[0005] Finally, when disassembling traditional automotive piston molding dies, due to the special structure of automotive pistons, the external molding die and the internal molding die of the piston need to be disassembled in sections. The demolding process is cumbersome and lacks simplicity and speed, which reduces the convenience and flexibility of the actual use of piston molding dies. Summary of the Invention

[0006] The purpose of this invention is to provide a casting and molding apparatus for automobile piston production, so as to solve the problems mentioned in the background art.

[0007] To achieve the above objectives, the present invention provides the following technical solution: a casting molding apparatus for automobile piston production, comprising a bottom mold, a side mold, an inner mold, and an exhaust pipe;

[0008] The bottom mold and the inner mold are disposed between the two side molds, and the exhaust pipe is disposed at the top of the inner mold;

[0009] The bottom mold includes a plunger and a casting port, the casting port being opened inside the bottom mold, and the plunger being slidably installed inside the casting port;

[0010] The inner mold includes a riser located at the top of the inner mold;

[0011] The exhaust pipe comprises a second spring, an overflow bin, an isolation bin and a pressure relief valve, the riser and the isolation bin are communicated with the overflow bin respectively, the second spring and the pressure relief valve are arranged in the interior of the exhaust pipe respectively, and the pressure relief valve is located in the interior of the second spring;

[0012] The pressure relief valve comprises a sealing ring, the sealing ring is arranged at the bottom end of the pressure relief valve, and the outer wall of the sealing ring is matched with the inner wall of the isolation bin.

[0013] Preferably, the number of the side mold is one or more;

[0014] The inner wall of the side mold is provided with a forming pin, the surface of the inner mold is provided with a forming hole, and the inner wall of the forming hole is provided with a locking groove.

[0015] Preferably, the base is arranged in the interior of the base;

[0016] The base comprises a positioning pin and a positioning hole, the number of the positioning pin is one or more, and the number of the positioning hole is one or more;

[0017] The positioning hole is located at the edge of the base, and the positioning pin is inserted into the interior of the positioning hole;

[0018] The side mold comprises a positioning rod, and the positioning rod is arranged at the bottom end of the side mold.

[0019] Preferably, the bottom mold comprises an air hole and a one-way valve, one end of the air hole is communicated with the pouring opening, and the air outlet end of the one-way valve is communicated with the air hole;

[0020] The number of the air hole is one or more, the number of the one-way valve is one or more, and the number of the air hole is the same as that of the one-way valve.

[0021] Preferably, the plunger comprises a taper block, and the taper block is located at the top end of the plunger;

[0022] The volume of the taper block is less than the sum of the volume of the overflow bin and the riser;

[0023] The volume of the taper block is less than the volume of the isolation bin.

[0024] Preferably, the pressure relief valve comprises a valve bead, a third spring and a knob, the third spring is arranged in the interior of the pressure relief valve, and the two ends of the third spring are connected with the valve bead and the knob respectively;

[0025] The knob is rotatably arranged in the interior of the pressure relief valve, and the outer wall of the knob and the inner wall of the pressure relief valve are respectively provided with threads engaged with each other.

[0026] Preferably, the base comprises one or more stroke holes and one or more flow guide holes, and one end of the flow guide hole is in communication with the open end of the stroke hole.

[0027] The inner wall of the opening of the stroke hole is provided with an oil seal.

[0028] Preferably, the side mold comprises one or more first piston rods and one or more first springs.

[0029] The first spring is arranged on one side end face of the first piston rod.

[0030] The first piston rod is respectively slidably arranged in the interior of the stroke hole, and the surface of the first piston rod is in close contact with the inner wall of the oil seal.

[0031] The interior of one end of the stroke hole away from the first spring is filled with hydraulic oil.

[0032] Preferably, the linkage mechanism comprises one or more linkage mechanisms.

[0033] The linkage mechanism comprises one or more stroke pipes and one or more buffer bins.

[0034] The buffer bin is in communication with the stroke pipe and the flow guide hole, respectively.

[0035] Preferably, the inner mold comprises one or more stroke frames.

[0036] The surface of the stroke frame is provided with one or more second piston rods, fourth springs and sealing plugs, and the second piston rod and the sealing plug are connected by the fourth spring, respectively.

[0037] The second piston rod, the fourth spring and the sealing plug are respectively slidably arranged in the interior of the stroke pipe.

[0038] Compared with the prior art, the beneficial effects of the present application are:

[0039] 1. The piston casting device provided by the present application achieves the effect of eliminating the residual raw material at the pouring port and the riser of the casting by setting the plunger and the exhaust pipe. The plunger can retract after the injection of the raw material is completed, keeping the surface of the plunger flush with the surface of the bottom mold, so that the surface of the plunger is in a flat state, eliminating the residual raw material at the pouring port. In addition, the exhaust pipe relies on the movement of the pressure relief valve and the second spring to retract the raw material from the riser to the cavity, eliminating the residual raw material of the piston casting at the riser, improving the completion of the piston casting, reducing the subsequent surface treatment process of the piston, improving the efficiency of the piston casting, and improving the utilization rate of the casting raw material.

[0040] 2. The present application achieves the effect of improving the demolding efficiency by setting the linkage mechanism. The linkage mechanism connects the actions of the side mold and the inner mold through the reciprocating transmission of hydraulic oil, can drive the inner mold to rise during the separation of the side mold, can more quickly unfold the side mold and the inner mold, and can more conveniently take out the molded piston, facilitating the quick demolding operation of the staff. Conversely, after the piston is taken out, the reset of the inner mold can drive the hydraulic oil in the linkage mechanism to drive the side mold to reset in linkage, so that the synchronous reset of the side mold and the inner mold is more convenient, and the efficiency of the actual operation can be effectively improved. BRIEF DESCRIPTION OF DRAWINGS

[0041] Figure 1 It is a demolding state schematic diagram in the embodiment one of the present application;

[0042] Figure 2 It is a casting state schematic diagram in the embodiment one of the present application;

[0043] Figure 3 It is a main cross-sectional structure schematic diagram in the embodiment one of the present application;

[0044] Figure 4 It is a base and bottom mold appearance structure schematic diagram in the embodiment one of the present application;

[0045] Figure 5 It is a base and bottom mold main cross-sectional structure schematic diagram in the embodiment one of the present application;

[0046] Figure 6 It is a plunger ejection state schematic diagram in the embodiment one of the present application;

[0047] Figure 7 It is a side mold appearance structure schematic diagram in the embodiment one of the present application;

[0048] Figure 8 It is an inner mold appearance structure schematic diagram in the embodiment one of the present application;

[0049] Figure 9 It is an exhaust pipe appearance structure schematic diagram in the embodiment one of the present application;

[0050] Figure 10 This is a schematic diagram of the main cross-sectional structure of the exhaust pipe in Embodiment 1 of the present invention;

[0051] Figure 11 This is a partial main sectional view of the exhaust pipe in Embodiment 1 of the present invention;

[0052] Figure 12 This is a schematic diagram of the external structure of the pressure relief valve in Embodiment 1 of the present invention;

[0053] Figure 13 This is a schematic diagram of the main cross-sectional structure of the pressure relief valve in Embodiment 1 of the present invention;

[0054] Figure 14 This is a partial cross-sectional view of the linkage mechanism in Embodiment 2 of the present invention;

[0055] Figure 15 This is a schematic diagram of the bottom section of the base, bottom mold, and linkage mechanism in Embodiment 2 of the present invention;

[0056] Figure 16 This is a schematic diagram of the main cross-sectional structure of the stroke hole in Embodiment 2 of the present invention;

[0057] Figure 17 This is a schematic diagram of the main cross-sectional structure of the linkage mechanism in Embodiment 2 of the present invention.

[0058] In the picture:

[0059] 100. Base; 110. Locating pin; 120. Locating hole; 130. Stroke hole; 140. Guide hole;

[0060] 200. Bottom mold; 210. Piston; 211. Cone block; 220. Casting gate; 230. Air vent; 240. Check valve;

[0061] 300, side mold; 310, positioning rod; 320, first piston rod; 330, first spring; 340, forming pin;

[0062] 400. Inner mold; 410. Stroke frame; 411. Second piston rod; 412. Fourth spring; 413. Sealing plug; 420. Riser; 430. Forming hole; 431. Locking groove;

[0063] 500. Exhaust pipe; 510. Second spring; 520. Overflow chamber; 530. Isolation chamber; 540. Pressure relief valve; 541. Sealing ring; 542. Valve ball; 543. Third spring; 544. Knob;

[0064] 600. Linkage mechanism; 610. Travel tube; 620. Buffer chamber. Detailed Implementation

[0065] With reference to the drawings of the embodiments of the present application, the technical solutions in the embodiments of the present application will be clearly and completely described. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments of the present application, all the other embodiments obtained by a person of ordinary skill in the art without creative effort belong to the scope of protection of the present application.

[0066] With reference to the drawings of the embodiments of the present application, the technical solutions in the embodiments of the present application will be clearly and completely described. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments of the present application, all the other embodiments obtained by a person of ordinary skill in the art without creative effort belong to the scope of protection of the present application. Figures 1 to 17 The present application provides the following two embodiments:

[0067] Embodiment one:

[0068] With reference to the drawings of the embodiments of the present application, the technical solutions in the embodiments of the present application will be clearly and completely described. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments of the present application, all the other embodiments obtained by a person of ordinary skill in the art without creative effort belong to the scope of protection of the present application. Figures 1 to 3 A piston production casting forming device, comprising a bottom die 200, a side die 300, an inner die 400 and an exhaust pipe 500.

[0069] It is worth noting that the number of forming device bodies is one or more, and specifically, the number of forming device bodies is multiple.

[0070] When applied to low-pressure casting, the aluminum liquid injection pipe in the low-pressure casting equipment sequentially injects aluminum liquid into the inside of the forming device body, multiple forming device bodies are used alternately, and the sequence of injection, waiting for solidification, demolding, cavity cleaning, spraying of demolding agent, closing, preheating and re-injection is used in circulation. The production efficiency of the forming device body is improved.

[0071] It is worth noting that the number of side dies 300 is one or more, the inner wall of the side die 300 is provided with a forming pin 340, and the two side surfaces of the inner die 400 are respectively provided with a forming hole 430, and the inner wall of the forming hole 430 is respectively provided with a locking groove 431.

[0072] Specifically, with reference to Figure 1 and Figure 2 The number of side dies 300 is two, and the two side dies 300 are symmetrically distributed on the two sides of the inner die 400. After the two side dies 300 are closed, an outer wall cavity of the piston is formed.

[0073] The forming hole 430 and the forming pin 340 are combined to form a pin hole of the piston body, and the edge of the forming pin 340 is inserted into the locking groove 431 to lock the inner die 400, prevent the inner die 400 from shaking and separating, and avoid instability of the inner die 400 during casting and ensure the closeness between the inner die 400, the side die 300 and the bottom die 200.

[0074] With reference to the drawings of the embodiments of the present application, the technical solutions in the embodiments of the present application will be clearly and completely described. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments of the present application, all the other embodiments obtained by a person of ordinary skill in the art without creative effort belong to the scope of protection of the present application. Figure 1 The bottom die 200 and the inner die 400 are arranged between the two side dies 300, and the exhaust pipe 500 is arranged at the top end of the inner die 400.

[0075] Specifically, after the bottom die 200, the side die 300, and the inner die 400 are closed, the upper surface of the bottom die 200, the inner wall of the side die 300, and the outer wall of the inner die 400 form a mold cavity, and the shape of the mold cavity is the shape of the finished piston.

[0076] Secondly, the forming hole 430 cooperates with the forming pin 340 to form a pin hole cavity of the piston. After the side die 300 and the inner die 400 are completely attached, the forming pin 340 is inserted into the locking groove 431 of the forming hole 430, and the two side dies 300 simultaneously lock the two sides of the inner die 400 through the forming pin 340, thereby locking the position of the inner die 400 between the side dies 300, avoiding the problem of shaking of the inner die 400, affecting the casting precision, and also avoiding the problem of separation of the inner die 400 from the two side dies 300.

[0077] Please refer to Figures 3 to 6 , the bottom die 200 includes a plunger 210 and a pouring hole 220. Specifically, the aluminum liquid output pipe of the low-pressure casting machine is combined with the pouring hole 220, which is used to inject aluminum liquid into the mold cavity through the pouring hole 220.

[0078] Specifically, please refer to Figure 5 and Figure 6 , the plunger 210 includes a tapered block 211, and the tapered block 211 is located at the top end of the plunger 210.

[0079] Please refer to Figure 5 , the pouring hole 220 is opened in the inside of the bottom die 200, and the plunger 210 is slidingly installed in the inside of the pouring hole 220. The plunger 210 is used to realize one-way conduction of the pouring hole 220 and keep the surface of the bottom die 200 flat. When the aluminum liquid enters the inside of the mold cavity through the pouring hole 220, please refer to Figure 6 , the aluminum liquid can push the plunger 210 to rise, forming a gap between the plunger 210 and the inside of the pouring hole 220, and the aluminum liquid can enter the mold cavity through the gap between the plunger 210 and the pouring hole 220.

[0080] When the injection of the aluminum liquid is completed, the injection of the aluminum liquid in the pouring hole 220 is stopped, and the aluminum liquid output pipe of the low-pressure casting machine recycles the residual aluminum liquid inside, resulting in a negative pressure in the pouring hole 220, which drives the plunger 210 to fall, and the upper end of the plunger 210 seals the upper end of the pouring hole 220, preventing the problem of backflow of the aluminum liquid in the mold cavity. Secondly, after the plunger 210 is reset, the upper surface of the plunger 210 is flush with the surface of the bottom die 200, so that there is no aluminum liquid residue on the surface of the piston at the pouring hole 220, ensuring the casting completion degree of the surface of the piston.

[0081] Please refer to Figures 3 to 6 , it is worth noting that the bottom die 200 includes an air hole 230 and a one-way valve 240, one end of the air hole 230 is in communication with the pouring hole 220, and the air outlet end of the one-way valve 240 is in communication with the air hole 230.

[0082] The number of air holes 230 is one or more, the number of one-way valves 240 is one or more, and the number of air holes 230 is the same as that of one-way valves 240.

[0083] Specifically, the number of air holes 230 is one, and the number of one-way valves 240 is one.

[0084] It is worth noting that in the process of stopping the injection of molten aluminum in the pouring gate 220, and the molten aluminum output pipe of the low-pressure casting machine recycling the internal residual molten aluminum, causing the upper end of the plunger 210 to closely fit with the inner wall of the top end of the pouring gate 220, achieving a sealed state.

[0085] At this time, the pouring gate 220 forms a one-way air path with the outside through the air hole 230 and the one-way valve 240, and the outside air can enter the inside of the upper end of the pouring gate 220 through the one-way valve 240 and the air hole 230, so that the inside space of the upper end of the pouring gate 220 is no longer in a sealed state, and the residual molten aluminum in the pouring gate 220 can flow back to the molten aluminum holding furnace along the molten aluminum output pipe of the low-pressure casting machine, effectively avoiding the problem of residual molten aluminum in the pouring gate 220, and reducing the labor intensity of the staff in cleaning the pouring gate 220.

[0086] It is worth noting that the one-way valve 240 has the characteristic of one-way conduction, and in the process of injecting molten aluminum, the air in the air hole 230 cannot be transmitted to the outside through the one-way valve 240, causing the air in the air hole 230 to be in a state of being unable to circulate, and the air hole 230 is in a closed state, and the molten aluminum cannot enter the inside of the air hole 230, which will not cause the problem of clogging of the air hole 230.

[0087] Please refer to Figure 8 , the inner mold 400 includes a riser 420 located at the top end of the inner mold 400. The riser 420 is used for air discharge in the cavity and compensation of the internal space of the cavity.

[0088] Please refer to Figures 9 to 13 , the exhaust pipe 500 includes a second spring 510, an overflow bin 520, an isolation bin 530, and a pressure relief valve 540. The riser 420 and the isolation bin 530 are respectively communicated with the overflow bin 520, the second spring 510 and the pressure relief valve 540 are respectively arranged in the inside of the exhaust pipe 500, and the pressure relief valve 540 is located in the inside of the second spring 510.

[0089] It is worth noting that the volume of the taper block 211 is equal to the sum of the volumes of the overflow bin 520 and the riser 420, and the volume of the taper block 211 is less than the volume of the isolation bin 530.

[0090] When the plunger 210 is fully ejected, the molten aluminum continues to be injected into the cavity, and the lower surface of the tapered block 211 is flush with the upper surface of the bottom die 200, i.e., in the fully ejected state of the plunger 210, the tapered block 211 is fully inserted into the cavity.

[0091] Please refer to Figures 10 to 13 The pressure relief valve 540 comprises a sealing ring 541 arranged at the bottom end of the pressure relief valve 540, and the outer wall of the sealing ring 541 is in close contact with the inner wall of the isolation bin 530.

[0092] Please refer to Figure 10 and Figure 13 The pressure relief valve 540 comprises a valve bead 542, a third spring 543 and a knob 544, the third spring 543 is arranged inside the pressure relief valve 540, and the two ends of the third spring 543 are respectively connected with the valve bead 542 and the knob 544.

[0093] The knob 544 is rotatably arranged inside the pressure relief valve 540, the outer wall of the knob 544 and the inner wall of the pressure relief valve 540 are respectively provided with mating threads, and the upper surface of the knob 544 is provided with an internal hexagonal hole, which facilitates the use of a hexagonal wrench by the staff to adjust the position of the knob 544.

[0094] It is worth noting that a plurality of notches are arranged on the surface of the pressure relief valve 540, which is convenient for observing the position of the knob 544, and the surface of the notches can be provided with scales, which is beneficial to control the spring force value of the third spring 543 corresponding to the position of the knob 544.

[0095] In actual operation, the staff adjusts the position of the knob 544 by rotating the knob 544 with a hexagonal wrench according to the pressure of the molten aluminum output by the low-pressure casting machine, so that the knob 544 rises and falls inside the pressure relief valve 540, and the length of the third spring 543 is adjusted to adjust the pressure of the third spring 543 acting on the valve bead 542, thereby adjusting the air pressure of the pressure relief valve 540.

[0096] It is worth noting that the air pressure of the pressure relief valve 540 is the same as the pressure of the molten aluminum output by the low-pressure casting machine, and the spring force of the second spring 510 is smaller than the input pressure of the molten aluminum.

[0097] Specifically, after the molten aluminum continues to be output into the cavity, the plunger 210 is ejected, and the molten aluminum enters the cavity along the gap between the plunger 210 and the inner wall of the pouring gate 220. Since the spring force of the second spring 510 is smaller than the pressure when the molten aluminum is input, during the injection of the molten aluminum, as the molten aluminum continues to be injected at low pressure, the molten aluminum squeezes the air in the cavity, and the air in the cavity enters the overflow bin 520 through the riser 420. The air pressure in the overflow bin 520 gradually increases until it is greater than the spring force of the second spring 510, and the air pressure in the overflow bin 520 overcomes the pressure of the second spring 510 to lift the pressure relief valve 540, thereby connecting the overflow bin 520 and the isolation bin 530.

[0098] As the molten aluminum continues to fill the cavity, the air in the cavity gradually collects in the overflow bin 520 and the isolation bin 530, until the bottom end of the pressure relief valve 540 moves to the upper end of the isolation bin 530, and the pressure relief valve 540 stops moving, during which the air pressure in the isolation bin 530 gradually increases until the air pressure is greater than the input pressure of the molten aluminum, the air pressure overcomes the elastic force of the second spring 510, lifts the valve ball 542, and the air in the isolation bin 530 can be discharged through the hole at the bottom end of the pressure relief valve 540, keeping the air pressure in the isolation bin 530 constant, stabilizing the environment of low-pressure casting.

[0099] After the molten aluminum is fully injected, the single injection amount of the molten aluminum is the sum of the volume of the casting and the shrinkage allowance of the aluminum casting, the output pipe of the low-pressure casting machine stops outputting the molten aluminum, i.e. the input pressure at the pouring gate 220 disappears, the second spring 510 pushes the molten aluminum in the overflow bin 520 back to the cavity, and at the same time, the backflow of the molten aluminum can push the plunger 210 in the bottom die 200 to reset, the taper block 211 can close the upper end of the pouring gate 220, and the upper surface of the taper block 211 is flush with the surface of the bottom die 200, keeping the molten aluminum at the piston end flat, which can eliminate the residual material at the corners of the piston at the pouring gate 220.

[0100] After the input pressure of the molten aluminum at the pouring gate 220 disappears, the second spring 510 pushes the pressure relief valve 540 to move in the isolation bin 530 by the elastic force, since the volume of the taper block 211 is equal to the sum of the volumes of the overflow bin 520 and the riser 420, and the volume of the taper block 211 is less than the volume of the isolation bin 530.

[0101] After the taper block 211 is fully reset, the residual molten aluminum in the overflow bin 520 and the riser 420 is completely backflowed to the cavity during the resetting of the pressure relief valve 540, as compensation for the molten aluminum after the taper block 211 is reset and volume shrinkage during solidification of the molten aluminum.

[0102] When the input aluminum liquid volume is equal to the sum of the volume of the casting and the aluminum casting feeding amount, the overflow bin 520 and the riser 420 are completely filled with aluminum liquid, and when the aluminum liquid is retracted, the aluminum liquid remains in the overflow bin 520 and the riser 420 for feeding. During the solidification of the aluminum liquid, the aluminum liquid and the air remaining in the overflow bin 520 maintain the injection pressure. The pressure relief valve 540 is pushed out by the elastic force of the third spring 543, maintaining the airtight state of the pressure relief valve 540. The air pressure in the isolation bin 530 is less than the elastic force of the third spring 543, so the air cannot be discharged from the pressure relief valve 540 to the outside, but only remains in the isolation bin 530. The residual aluminum liquid in the isolation bin 530 remains under the action of the gas pressure, continuously compensating for the depression at the position of the riser 420 during the solidification of the casting. When the casting is completely solidified, the residual aluminum liquid in the overflow bin 520 and the riser 420 is completely compensated to the metal retraction at the riser 420 of the casting, thereby forming a flat casting plane.

[0103] Through the action of air pressure, the surface of the piston casting at the riser 420 can form a regular plane, avoiding the formation of excess aluminum liquid in the riser 420 and affecting the subsequent demolding effect. At the same time, the aluminum block at the riser 420 also affects the overall casting completion of the piston casting and increases the cost of subsequent processing procedures.

[0104] Through the reset of the plunger 210 and the reset of the pressure relief valve 540 in the isolation bin 530, the aluminum liquid in the cavity is retracted and compensated, effectively avoiding the formation of excess aluminum liquid in the riser 420 and affecting the subsequent demolding effect. The surface of the piston casting after demolding is more flat and has higher completion, and there is no need to remove the residual excess aluminum liquid on the surface of the piston casting, saving production procedures and reducing production cost.

[0105] Embodiment two:

[0106] Based on the above content of embodiment one, another embodiment is proposed:

[0107] Please refer to Figures 1 to 3 , the automobile piston production casting forming device further comprises a base 100, the bottom die 200 is arranged in the interior of the base 100, and the base 100 is used for improving the stability of the whole forming device body.

[0108] Please refer to Figure 4 , the base 100 comprises a positioning pin 110 and a positioning hole 120, the number of the positioning pin 110 is one or more, and the number of the positioning hole 120 is one or more. Specifically, the number of the positioning hole 120 is two, and the number of the positioning pin 110 is two.

[0109] The positioning hole 120 is respectively located at the edge of the base 100, and the positioning pin 110 is inserted into the interior of the positioning hole 120.

[0110] It is worth noting that the side mold 300 includes a positioning rod 310, which is arranged at the bottom end of the side mold 300. When the positioning pin 110 is inserted into the positioning hole 120, the position of the positioning rod 310 can be limited, which is used to fix the position of the side mold 300, maintain the clamping state of the side mold 300 and the inner mold 400, and form a closed and stable cavity.

[0111] Please refer to Figure 15 , the base 100 includes one or more stroke holes 130 and one or more flow guide holes 140, and one end of the flow guide hole 140 is in communication with the open end of the stroke hole 130. Specifically, the number of stroke holes 130 is four, and the four stroke holes 130 are symmetrically distributed at both ends of the base 100. Specifically, the number of flow guide holes 140 is four.

[0112] Please refer to Figure 7 , the side mold 300 includes one or more first piston rods 320 and one or more first springs 330, and the first spring 330 is arranged on one side of the first piston rod 320.

[0113] Specifically, the number of first piston rods 320 in each side mold 300 is two, and the number of first springs 330 is two.

[0114] It is worth noting that the inner wall of the opening of the stroke hole 130 is provided with an oil seal, which is used to prevent the hydraulic oil from leaking from the surface of the first piston rod 320.

[0115] The first piston rod 320 is respectively slidably installed in the interior of the stroke hole 130, and the surface of the first piston rod 320 is in close contact with the inner wall of the oil seal.

[0116] It is worth noting that the interior of the end of the stroke hole 130 away from the first spring 330 is filled with hydraulic oil. Please refer to Figure 16 , the hydraulic oil and the first spring 330 are separated by the piston member at one end of the first piston rod 320.

[0117] Please refer to Figure 1 , Figure 2 and Figure 14 , the automobile piston production casting forming device further includes one or more linkage mechanisms 600.

[0118] Specifically, the number of linkage mechanisms 600 is two, and the two linkage mechanisms 600 are symmetrically distributed on both sides of the base 100.

[0119] Please refer to Figure 14 ,Figure 15 and Figure 17 The linkage mechanism 600 includes one or more stroke tubes 610 and one or more buffer chambers 620. The buffer chambers 620 are respectively communicated with the stroke tubes 610 and the flow guide holes 140.

[0120] Specifically, the number of the stroke tubes 610 in each linkage mechanism 600 is two, and the number of the buffer chambers 620 in each linkage mechanism 600 is two.

[0121] Please refer to Figure 8 The inner mold 400 further includes one or more stroke frames 410, and specifically one stroke frame 410.

[0122] The surface of the stroke frame 410 is mounted with one or more second piston rods 411, and the second piston rods 411 are respectively connected with the sealing plugs 413 through the fourth springs 412. The second piston rods 411 are respectively slidingly installed in the interiors of the stroke tubes 610.

[0123] Specifically, the number of the second piston rods 411 is four, and the four second piston rods 411, the fourth springs 412 and the sealing plugs 413 are respectively slidingly installed in the interiors of the stroke tubes 610.

[0124] Before the piston casting, the interior of the molding device body needs to be cleaned and sprayed with a release agent, and the molding device body needs to be preheated as a whole.

[0125] At this time, the casting molding device is in an unfolded state. In this state, the first spring 330 is in an unfolded state, the first piston rod 320 is pushed out by the elastic force of the first spring 330, the hydraulic oil in the stroke hole 130 is squeezed out to the buffer chamber 620 of the linkage mechanism 600 through the flow guide hole 140, and then is squeezed out to the stroke tube 610 by the buffer chamber 620, drives the second piston rod 411 to be pushed out, drives the stroke frame 410 and the inner mold 400 to rise, so that the side mold 300 and the inner mold 400 remain in an unfolded state, facilitating the work personnel to clean the surface of the bottom mold 200, the side mold 300 and the inner mold 400, spray the release agent, and demold and take out the molded piston casting.

[0126] When the mold is closed, the inner mold 400 is moved downward, the second piston rod 411 driven by the inner mold 400 reversely squeezes the hydraulic oil in the stroke tube 610 to the stroke hole 130, and in this process, the fourth spring 412 is in a compressed state. The hydraulic oil pushes the first piston rod 320 to move, and in the movement process of the first piston rod 320, one end of the first piston rod 320 squeezes the first spring 330, and the first spring 330 stores elastic potential energy in this process.

[0127] When the inner mold 400 is combined with the side mold 300, the positioning pin 110 is inserted into the positioning hole 120, the positioning pin 110 blocks the positioning rod 310 on the side mold 300, plays a role in positioning the side mold 300, maintains the closed state of the side mold 300, cooperates with the bottom mold 200 and the inner mold 400 to form a complete and closed cavity, and facilitates subsequent low-pressure casting operations.

[0128] After the aluminum liquid in the cavity is solidified, demolding can be performed, the positioning pin 110 is removed, the elastic potential energy stored by the first spring 330 is released, the first spring 330 pushes the first piston rod 320 out through the elastic force, and the hydraulic oil in the stroke hole 130 is extruded to the buffer bin 620 through the flow guide hole 140.

[0129] Due to the special structure of the pin hole forming position of the piston, when the side mold 300 is not completely separated from the pin hole position of the piston casting, the inner mold 400 cannot be separated from the piston casting, and therefore the buffer bin 620 and the fourth spring 412 are provided, the buffer bin 620 can preliminarily store the hydraulic oil, inject the hydraulic oil in the buffer bin 620 into the stroke pipe 610, and lift the sealing plug 413, the sealing plug 413 extrudes the fourth spring 412 to buffer the hydraulic oil, until the fourth spring 412 is completely extruded and the formed pin 340 is separated from the formed piston pin hole, the fourth spring 412 lifts the second piston rod 411 through the elastic force, and as the subsequent side mold 300 moves, the hydraulic oil continues to be injected into the stroke pipe 610, and the inner mold 400 continues to be linked and lifted.

[0130] Finally, the fully expanded state of the inner mold 400, the side mold 300 and the bottom mold 200 facilitates the removal of the formed piston casting and the cleaning of the inner wall of the cavity.

[0131] The linkage mechanism 600 links the actions between the side mold 300 and the inner mold 400, effectively improves the efficiency and use convenience of the mold opening and closing of the molding device body, and reduces the labor intensity of the workers while being more convenient in actual application.

[0132] It is obvious to those skilled in the art that the present application is not limited to the details of the above exemplary embodiments, and can be implemented in other specific forms without departing from the spirit or essential characteristics of the present application. Therefore, the embodiments should be regarded as exemplary and non-limiting, and the scope of the present application is defined by the appended claims rather than the above description, and all changes falling within the meaning and scope of the equivalent elements of the claims are intended to be included in the present application. Any reference signs in the claims should not be regarded as limiting the claims involved.

Claims

1. A casting and molding apparatus for automobile piston production, characterized in that: Includes bottom mold (200), side mold (300), inner mold (400) and vent pipe (500); The bottom mold (200) and the inner mold (400) are disposed between the two side molds (300), and the exhaust pipe (500) is disposed at the top of the inner mold (400); The bottom mold (200) includes a plunger (210) and a casting port (220). The casting port (220) is opened inside the bottom mold (200), and the plunger (210) is slidably installed inside the casting port (220). The bottom mold (200) includes an air hole (230) and a one-way valve (240). One end of the air hole (230) is connected to the casting port (220), and the air outlet of the one-way valve (240) is connected to the air hole (230). The number of air holes (230) is one or more, the number of one-way valves (240) is one or more, and the number of air holes (230) and one-way valves (240) is the same; The inner mold (400) includes a riser (420) located at the top of the inner mold (400); The exhaust pipe (500) includes a second spring (510), an overflow chamber (520), an isolation chamber (530), and a pressure relief valve (540). The riser (420) and the isolation chamber (530) are respectively connected to the overflow chamber (520). The second spring (510) and the pressure relief valve (540) are respectively disposed inside the exhaust pipe (500), and the pressure relief valve (540) is located inside the second spring (510). The plunger (210) includes a cone (211) located at the top of the plunger (210); The volume of the cone block (211) is less than the sum of the volumes of the overflow chamber (520) and the riser (420); The volume of the cone block (211) is smaller than the volume of the isolation chamber (530); The pressure relief valve (540) includes a sealing ring (541), which is disposed at the bottom end of the pressure relief valve (540), and the outer wall of the sealing ring (541) is in contact with the inner wall of the isolation chamber (530). The venting pressure of the pressure relief valve (540) is the same as the pressure of the aluminum liquid output from the low-pressure casting machine, and the elastic force of the second spring 510 is less than the aluminum liquid input pressure. During the aluminum liquid injection process, as the aluminum liquid is continuously injected at low pressure, the aluminum liquid compresses the air in the cavity. The air in the cavity enters the overflow chamber (520) through the riser (420). The air pressure in the overflow chamber (520) gradually increases until it exceeds the elastic force of the second spring (510). The air pressure in the overflow chamber (520) overcomes the pressure of the second spring (510) and pushes up the pressure relief valve (540), connecting the overflow chamber (520) with the isolation chamber (530). As molten aluminum is continuously injected into the mold cavity, the air in the mold cavity gradually gathers into the overflow chamber (520) and the isolation chamber (530) until the bottom end of the pressure relief valve (540) is moved to the top end of the isolation chamber (530). At this time, the pressure relief valve (540) stops moving. During this period, the air pressure in the isolation chamber (530) gradually increases until the air pressure is greater than the input pressure of the molten aluminum. Then the pressure relief valve (540) opens, and the air in the isolation chamber (530) can be released through the hole at the bottom end of the pressure relief valve (540).

2. The casting and molding apparatus for automobile piston production according to claim 1, characterized in that: The number of the side molds (300) is one or more; The inner wall of each side mold (300) is provided with a forming pin (340), and the two sides of the inner mold (400) are respectively provided with forming holes (430), and the inner wall of each forming hole (430) is respectively provided with a locking groove (431).

3. The casting and molding apparatus for automobile piston production according to claim 1, characterized in that: Includes a base (100), and the bottom mold (200) is disposed inside the base (100); The base (100) includes positioning pins (110) and positioning holes (120), wherein the number of positioning pins (110) is one or more, and the number of positioning holes (120) is one or more; The positioning holes (120) are located on the edges of the base (100), and the positioning pins (110) are inserted into the interior of the positioning holes (120); The side mold (300) includes a positioning rod (310), which is located at the bottom end of the side mold (300).

4. The casting and forming apparatus for automobile piston production according to claim 1, characterized in that: The pressure relief valve (540) includes a valve ball (542), a third spring (543) and a knob (544). The third spring (543) is disposed inside the pressure relief valve (540), and the two ends of the third spring (543) are respectively connected to the valve ball (542) and the knob (544). The knob (544) is rotatably installed inside the pressure relief valve (540), and the outer wall of the knob (544) and the inner wall of the pressure relief valve (540) are respectively provided with meshing threads.

5. The casting and molding apparatus for automobile piston production according to claim 3, characterized in that: The base (100) includes a stroke hole (130) and a flow guide hole (140). The number of stroke holes (130) is one or more, the number of flow guide holes (140) is one or more, and one end of the flow guide hole (140) is connected to the open end of the stroke hole (130). An oil seal is provided on the inner wall of the opening of the travel hole (130).

6. The casting and forming apparatus for automobile piston production according to claim 5, characterized in that: The side mold (300) includes a first piston rod (320) and a first spring (330), wherein the number of the first piston rod (320) is one or more, and the number of the first spring (330) is one or more; The first spring (330) is disposed on one end face of the first piston rod (320); The first piston rod (320) is slidably installed inside the stroke hole (130), and the surface of the first piston rod (320) is in contact with the inner wall of the oil seal; The end of the travel hole (130) away from the first spring (330) is filled with hydraulic oil.

7. A casting and forming apparatus for automobile piston production according to claim 5, characterized in that: Includes a linkage mechanism (600), wherein the number of linkage mechanisms (600) is one or more; The linkage mechanism (600) includes a stroke tube (610) and a buffer chamber (620), wherein the number of stroke tubes (610) is one or more, and the number of buffer chambers (620) is one or more; The buffer chamber (620) is connected to the travel tube (610) and the guide hole (140) respectively.

8. The casting and molding apparatus for automobile piston production according to claim 7, characterized in that: The inner mold (400) includes a travel frame (410), and the number of travel frames (410) is one or more; The surface of the stroke frame (410) is equipped with a second piston rod (411), a fourth spring (412) and a sealing plug (413). There are one or more second piston rods (411), and the fourth spring (412) is connected between the second piston rod (411) and the sealing plug (413). The second piston rod (411), the fourth spring (412), and the sealing plug (413) are slidably installed inside the stroke tube (610).

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