Inner cavity runner sand core

Abstract

The utility model relates to an inner cavity runner sand core which comprises an upper runner and a lower runner, the upper runner is arranged on the lower runner, the upper runner comprises an upper runner main body, a first positioning core head and a second positioning core head, the first positioning core head is provided with a first positioning part, and the second positioning core head is provided with a second positioning part; the lower runner comprises a lower runner main body, a third positioning core head and a fourth positioning core head, the third positioning core head is provided with a third positioning part matched with the first positioning part, and the fourth positioning core head is provided with a fourth positioning part matched with the third positioning part; the third positioning core head is further provided with a positioning protrusion, the outer circumferential wall of the positioning protrusion is connected with one end of the lower runner body, and the inner circumferential wall of the positioning protrusion is attached to the inner circumferential wall of the first positioning core head. According to the inner cavity runner sand core provided by the utility model, burrs generated on the junction surface of the upper runner and the lower runner appear on a processing surface, and finally, the generated burrs are removed through processing, a gluing tool is removed, and a repairing process is canceled.

Description

Technical Field

[0001] The utility model relates to an inner cavity flow channel sand core. Background Art

[0002] With the improvement of emission requirements, the inner cavity structure of turbochargers has been optimized. Tests have found that the turbine shell product with double tongue structure can improve fuel efficiency and reduce emissions, and has gradually become the mainstream design of turbine shells. However, the flow channel of this design is difficult to type. The traditional flow channel design will bring great difficulties to production, which are specifically manifested as follows:

[0003] 1. See Figure 9-16 , the flow channel sand core includes an upper flow channel 3 and a lower flow channel 4, a plurality of positioning parts 31 are arranged on the upper flow channel 3, a plurality of matching parts 41 matching with the positioning parts are arranged on the lower flow channel 4, the flow channel gluing matching surfaces on the lower flow channel 4 are represented by a and b, the flow channel gluing matching surfaces on the upper flow channel 3 are represented by c and d, the flow channel gluing matching surface of the lower flow channel 4 is in contact with the flow channel gluing matching surface of the upper flow channel 3 (the circumferential gluing seam is represented by m, and the burr position of the circumferential gluing seam product is shown in n), the matching area is small, the position of the ejector rod is represented by e (a single sand core plus an ejector rod is not ejected flat, and an ejector rod needs to be added to the product surface), the center of gravity position is represented by f, and the sand core is unstable; the tongue 1 and the tongue 2 refer to j and k in the figure; the joint surfaces between the upper flow channel 3 and the lower flow channel 4 need to be repaired with mold repair paste, the production process is complicated, the circulation cycle is long, and the cost is high;

[0004] 2. Since the center of gravity of the sand core is offset, the sand core is unstable and needs to be glued by the sand core gluing tool 5. A plurality of positioning points 51 and supporting points 52 are arranged on the sand core gluing tool 5. The gluing tool costs about 2,000 yuan per pair, which increases the mold cost.

[0005] 3. There will inevitably be gaps at the gluing position. This combined gap needs to be filled with casting repair paste by workers. The production is difficult and the cycle is long, which will also increase the production cost. The repair fee is 1 yuan / piece, and the circulation cycle is 1 day longer than the normal flow channel;

[0006] 4. The repair paste and the runner sand core are not made of the same material. Under the action of molten iron, the repair paste and the sand core are easily separated, so the molten iron has a chance to penetrate into the gap to form the product flash. Moreover, this flash is generated in the inner cavity of the product and cannot be reworked by grinding, which increases the scrap rate of such products, which is about 2%. However, in the automotive parts industry, prices need to be reduced every year, and the increase in production costs has greatly compressed the living space of foundries. Utility Model Content

[0007] The utility model aims to provide a sand core with an inner cavity flow channel.

[0008] In order to achieve the above purpose, the technical solution adopted by the utility model is:

[0009] An inner cavity flow channel sand core comprises an upper flow channel and a lower flow channel matched with each other, wherein the upper flow channel is arranged on the lower flow channel, and the upper flow channel comprises an upper flow channel body, a first positioning core head and a second positioning core head, wherein the first positioning core head and the second positioning core head are respectively arranged at opposite ends of the upper flow channel body, wherein the first positioning core head is provided with a first positioning portion, and the second positioning core head is provided with a second positioning portion;

[0010] The lower flow channel comprises a lower flow channel body, a third positioning core head and a fourth positioning core head, wherein the third positioning core head and the fourth positioning core head are respectively arranged at opposite ends of the lower flow channel body, the third positioning core head is provided with a third positioning portion matched with the first positioning portion, the fourth positioning core head is provided with a fourth positioning portion matched with the third positioning portion, and the central axes of the first positioning portion and the third positioning portion extend in the same straight line direction;

[0011] A positioning protrusion is also provided on the third positioning core head. The positioning protrusion and the third positioning portion are located on the same side of the third positioning core head. The positioning protrusion is arc-shaped. The outer peripheral wall of the positioning protrusion is connected to one end of the lower flow channel body, and the inner peripheral wall of the positioning protrusion is in contact with the inner peripheral wall of the first positioning core head.

[0012] In some embodiments, the first positioning core head includes a main body, a first arc-shaped connecting part, and a second arc-shaped connecting part. The main body is cylindrical. The first arc-shaped connecting part is arranged on the periphery of the main body and circumferentially arranged around the periphery of the main body. The inner circumferential wall of the positioning protrusion is in contact with the outer circumferential wall of the main body where the first arc-shaped connecting part is not arranged and the outer circumferential wall of the first arc-shaped connecting part. The second arc-shaped connecting part is arranged on a side of the first arc-shaped connecting part away from the main body, and the second arc-shaped connecting part is connected to one end of the upper flow channel main body.

[0013] In some embodiments, the positioning protrusion, the first arc-shaped connecting portion, and the main body form a full circle.

[0014] In some embodiments, the first positioning portion is a recessed structure recessed in the surface of the first positioning core head, and the third positioning portion protrudes from the surface of the third positioning core head; the second positioning portion protrudes from the surface of the second positioning core head, and the fourth positioning portion is a recessed structure recessed in the surface of the fourth positioning core head.

[0015] In some embodiments, the third positioning portion has a circular cross-section, and the second positioning portion has a circular cross-section.

[0016] In some embodiments, the diameter of the third positioning portion gradually decreases from close to the third positioning core head to away from the third positioning core head; and\or the diameter of the second positioning portion gradually decreases from close to the second positioning core head to away from the second positioning core head.

[0017] In some embodiments, the third positioning core head is cylindrical, the third positioning portion is located in the middle of the third positioning core head, and the third positioning core head is concentrically arranged with the third positioning portion.

[0018] In some embodiments, an upwardly recessed groove is provided on the lower side of the third positioning core head, and an annular positioning boss is provided on the lower side of the third positioning core head, and the annular positioning boss is arranged around the surface edge of the groove; the third positioning core head, the third positioning part, and the first positioning part are provided with interconnected through holes, and the through holes penetrate the groove.

[0019] In some embodiments, one of each of the first positioning portion, the second positioning portion, the third positioning portion, and the fourth positioning portion is provided.

[0020] In some embodiments, a first extension portion is provided on the upper flow channel body, and a second extension portion is provided on the lower flow channel body, and an end of the first extension portion away from the upper flow channel body is opposite to an end of the second extension portion away from the lower flow channel body.

[0021] Due to the application of the above technical solution, the utility model has the following advantages compared with the prior art:

[0022] The inner cavity flow channel sand core provided by the utility model makes the flash generated by the joint surface of the upper flow channel and the lower flow channel appear on the processing surface, and finally the flash is removed by processing, thereby achieving the purpose of removing the gluing tooling and canceling the repair process, eliminating the waste that may be generated in the repair process, speeding up the circulation time, and greatly reducing the production cost of such products. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Attached Figure 1 A structural diagram of the lower flow channel of the inner cavity flow channel sand core provided by the utility model from a first perspective;

[0024] Attached Figure 2 A structural diagram of the lower flow channel of the inner cavity flow channel sand core provided by the utility model from a second perspective;

[0025] Attached Figure 3 A structural diagram of the lower flow channel of the inner cavity flow channel sand core provided by the utility model from a third perspective;

[0026] Attached Figure 4A structural diagram of the upper flow channel of the inner cavity flow channel sand core provided by the utility model from a first perspective;

[0027] Attached Figure 5 A structural diagram of the upper flow channel of the inner cavity flow channel sand core provided by the utility model from a second perspective;

[0028] Attached Figure 6 A structural diagram of the inner cavity flow channel sand core provided by the utility model;

[0029] Attached Figure 7 A structural diagram of a turbocharger made using the inner cavity flow channel sand core provided by the utility model;

[0030] Attached Figure 8 This is a structural diagram of a turbocharger made using an existing inner cavity flow channel sand core;

[0031] Attached Fig. 9 This is the structural diagram of the downflow channel before improvement;

[0032] Attached Fig.10 This is a structural diagram of the upper flow channel from the first perspective before improvement;

[0033] Attached Fig.11 This is a structural diagram of the upper flow channel from a second perspective before improvement;

[0034] Attached Fig.12 This is a structural diagram from the first perspective after the upper flow channel and the lower flow channel are glued together before improvement;

[0035] Attached Fig.13 This is a structural diagram from a second perspective after the upper flow channel and the lower flow channel are glued together before improvement;

[0036] Attached Fig.14 To improve the structure of the glued tooling before;

[0037] Attached Fig.15 To improve the structure of the front downflow channel placed on the gluing tooling;

[0038] Attached Fig.16 To improve the structure of placing the front upper flow channel and the lower flow channel on the gluing tooling.

[0039] In the above attached figure:

[0040] 1-upper flow channel, 11-upper flow channel body, 12-main body, 121-first surface, 122-second surface, 13-first arc-shaped connecting portion, 14-second positioning core head, 15-first positioning portion, 16-second positioning portion, 17-limiting protrusion, 18-first extending portion, 19-second arc-shaped connecting portion;

[0041] 2-downstream channel, 21-downstream channel body, 22-third positioning core head, 221-upper surface of the third positioning core head, 23-positioning protrusion, 24-fourth positioning core head, 241-upper surface of the fourth positioning core head, 25-third positioning portion, 26-fourth positioning portion, 27-annular positioning boss, 28-second extension portion; 6-turbocharger. DETAILED DESCRIPTION

[0042] The technical solution of the utility model will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0043] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0044] See also Figures 1 to 8 The inner cavity flow channel sand core shown in the figure relates to the parting structure of the inner cavity sand core of the double-tongue turbocharger volute. The inner cavity flow channel sand core comprises a matching upper flow channel 1 and a lower flow channel 2. The upper flow channel 1 is arranged on the lower flow channel 2, wherein:

[0045] The upper flow channel 1 includes an upper flow channel body 11, a first positioning core head and a second positioning core head 14. The first positioning core head and the second positioning core head 14 are respectively arranged at opposite ends of the upper flow channel body 11. The first positioning core head is provided with a first positioning portion 15, and the second positioning core head 14 is provided with a second positioning portion 16. The upper flow channel body 11 is arc-shaped.

[0046] The downflow channel 2 comprises a downflow channel main body 21, a third positioning core head 22 and a fourth positioning core head 24. The downflow channel main body 21 is arc-shaped. The third positioning core head 22 and the fourth positioning core head 24 are respectively arranged at opposite ends of the downflow channel main body 21. The third positioning core head 22 is provided with a third positioning portion 25 matched with the first positioning portion 15, and the fourth positioning core head 24 is provided with a fourth positioning portion 26 matched with the third positioning portion 25, that is, the first positioning core head is arranged on the third positioning core head 22, and the third positioning core head 22 corresponds to the first positioning core head, the second positioning core head 14 is arranged on the fourth positioning core head 24, and the fourth positioning core head 24 corresponds to the second positioning core head 14, and the downflow channel main body 21 is located below the upflow channel main body 11; the first positioning portion 15 and the third positioning portion 25 are concentrically arranged, and the central axes of the first positioning portion 15 and the third positioning portion 25 extend along the same straight line direction.

[0047] The third positioning portion 25 is arranged on the upper surface 221 of the third positioning core head 22, and the first positioning portion 15 is located on the lower surface of the first positioning core head. The upper surface 221 of the third positioning core head 22 fits with the lower surface of the first positioning core head to form a flow channel gluing fitting surface with a large fitting range.

[0048] A positioning protrusion 23 is also provided on the upper surface 221 of the third positioning core head 22. The positioning protrusion 23 is close to the edge of the third positioning core head 22. The positioning protrusion 23 and the third positioning portion 25 are both located on the upper surface 221 of the third positioning core head 22. The positioning protrusion 23 is arc-shaped, and the curvature of the positioning protrusion 23 is consistent with the curvature of the outer periphery of the corresponding third positioning core head 22. The outer peripheral wall of the positioning protrusion 23 is connected to one end of the lower flow channel body 21, and the inner peripheral wall of the positioning protrusion 23 is in contact with the inner peripheral wall of the first positioning core head.

[0049] The first positioning core head includes a main body 12, a first arc-shaped connecting portion 13, and a second arc-shaped connecting portion 19. The main body 12 is cylindrical, and the first positioning portion 15 is arranged on the lower side of the main body 12; the first arc-shaped connecting portion 13 is arranged on the outer periphery of the main body 12 and is circumferentially arranged around the outer periphery of the main body 12, and the first arc-shaped connecting portion 13 is not a whole ring; the second arc-shaped connecting portion 19 is arranged on the side of the first arc-shaped connecting portion 13 away from the main body 12, and the second arc-shaped connecting portion 19 is connected to the upper flow channel main body 11, and the inner peripheral wall of the positioning protrusion 23 is in contact with the arc-shaped outer peripheral wall of the main body 12 where the first arc-shaped connecting portion 13 is not arranged, and the outer side wall of the first arc-shaped connecting portion 13, and the contact part (see Figure 6 The "w" in the middle refers to the glue-coated part where the parts are fitted together (the part where glue is applied). The parting surface is designed on the processing surface. Through processing, the flash generated by the flow channel joint surface can be removed, thereby canceling the repair process, eliminating the waste that may be generated by the repair process, speeding up the circulation time, and greatly reducing the production cost.

[0050] See also Figure 4-6 The positioning protrusion 23 forms a whole circle with the first arc-shaped connecting portion 13 and the main body 12 (the outer periphery of the positioning protrusion 23 and the outer periphery of the first arc-shaped connecting portion 13 form a circle), and the main body 12 is coaxially arranged with the first positioning portion 15 and the third positioning portion 25.

[0051] The main body 12 of the first positioning core head has a first surface 121 and a second surface 122 that are arranged opposite to each other, the first surface 121 faces downward, the second surface 122 faces upward, and the first surface 121 and the second surface 122 are both horizontal planes. The first positioning portion 15 is located on the first surface 121, and a limiting protrusion 17 is arranged on the second surface 122. The limiting protrusion 17 is arranged on the main body 12, and the limiting protrusion 17 is cylindrical. The limiting protrusion 17, the main body 12, and the first positioning portion 15 are provided with interconnected through holes; the first surface 121 is in contact with the upper surface of the third positioning portion 25 of the third positioning core head 22, and the matching surface area is large. At the same time, the positioning protrusion 23 is combined with the first positioning core head, and the placement is stable, and no gluing tooling is required.

[0052] By improving the parting method of the double-tongue inner cavity core and equally dividing the common parts of the upper and lower flow channels, the sand core can be placed flat and stable, thereby facilitating gluing. In addition, by adjusting the position of the sand core parting, the flash generated by the joint surface of the upper and lower flow channels appears on the processing surface, and finally the flash generated is removed by processing, achieving the purpose of removing the gluing tooling and canceling the repair process, greatly reducing the production cost of this type of turbocharger 6 product.

[0053] In some embodiments, the first positioning portion 15 is a recessed structure recessed on the surface of the first positioning core head, and the third positioning portion 25 protrudes from the upper surface of the third positioning core head 22; the second positioning portion 16 protrudes from the surface of the second positioning core head 14, and the fourth positioning portion 26 is a recessed structure recessed on the upper surface 241 of the fourth positioning core head 24 (the upper surface 241 of the fourth positioning core head 24 and the lower surface of the second positioning core head 14 are both horizontal planes, which are the flow channel gluing mating surfaces). When the upper flow channel 1 is set on the lower flow channel 2, the first positioning portion 15 is recessed upward, the third positioning portion 25 protrudes upward, the second positioning portion 16 protrudes downward, and the fourth positioning portion 26 is recessed downward.

[0054] The third positioning portion 25 of this example has a circular cross section, and the second positioning portion 16 has a circular cross section. The diameter of the third positioning portion 25 gradually decreases from the direction close to the third positioning core head 22 to the direction away from the third positioning core head 22. The diameter of the second positioning portion 16 gradually decreases from the direction close to the second positioning core head 14 to the direction away from the second positioning core head 14.

[0055] In some embodiments, the third positioning core head 22 is cylindrical, the upper surface of the third positioning core head 22 on which the third positioning portion 25 is provided is a horizontal plane, the third positioning portion 25 is located in the middle of the third positioning core head 22, and the third positioning core head 22 is concentrically arranged with the third positioning portion 25. In this example, the third positioning core head 22, the third positioning portion 25, the first positioning portion 15, and the limiting protrusion 17 are provided with intersecting through holes, which extend in the vertical direction; the through holes are circular holes.

[0056] See also Figure 2-3 An annular positioning boss 27 is provided on the lower side of the third positioning core head 22. An upwardly recessed groove is opened on the lower side of the third positioning core head 22. The annular positioning boss 27 is arranged around the surface edge of the groove. The through hole on the third positioning core head 22 passes through the groove.

[0057] The upper flow channel body 11 is provided with a first extension portion 18 , and the lower flow channel body 21 is provided with a second extension portion 28 . One end of the first extension portion 18 away from the upper flow channel body 11 is opposite to one end of the second extension portion 28 away from the lower flow channel body 21 .

[0058] In a preferred embodiment, one of each of the first positioning portion 15 , the second positioning portion 16 , the third positioning portion 25 and the fourth positioning portion 26 is provided.

[0059] Figure 8 The turbocharger can also be manufactured by using the inner cavity flow channel sand core of this example.

[0060] The advantages of the inner channel sand core in this example are:

[0061] 1. The flash produced by the joint surface of the upper flow channel and the lower flow channel appears on the processing surface, and the flash produced is finally removed through processing. No defects have ever been produced and no repair is required. The purpose of removing the gluing tooling and canceling the repair process is achieved, which greatly reduces the production cost of such products.

[0062] 2. The contact area of ​​the first positioning core head of the upper flow channel and the third positioning core head of the lower flow channel is larger, and the positioning is more stable, so the gluing tooling can be eliminated and direct gluing can be performed;

[0063] 3. The first positioning core head of the upper flow channel has a larger area. When making the core, the ejector pin can be placed entirely on the core head and the processing surface, thus eliminating the extra repairs and waste caused by the ejector pin.

[0064] The above embodiments are only for illustrating the technical concept and features of the utility model, and their purpose is to enable people familiar with the technology to understand the content of the utility model and implement it accordingly, and they cannot be used to limit the protection scope of the utility model. Any equivalent changes or modifications made according to the spirit of the utility model should be included in the protection scope of the utility model.

Claims

1. An inner cavity flow channel sand core, characterized in that: It comprises an upper flow channel and a lower flow channel, wherein the upper flow channel is arranged on the lower flow channel, and the upper flow channel comprises an upper flow channel body, a first positioning core head and a second positioning core head, wherein the first positioning core head and the second positioning core head are respectively arranged at opposite ends of the upper flow channel body, the first positioning core head is provided with a first positioning portion, and the second positioning core head is provided with a second positioning portion; The lower flow channel comprises a lower flow channel body, a third positioning core head and a fourth positioning core head, wherein the third positioning core head and the fourth positioning core head are respectively arranged at opposite ends of the lower flow channel body, the third positioning core head is provided with a third positioning portion matched with the first positioning portion, the fourth positioning core head is provided with a fourth positioning portion matched with the third positioning portion, and the central axes of the first positioning portion and the third positioning portion extend in the same straight line direction; A positioning protrusion is also provided on the third positioning core head. The positioning protrusion and the third positioning portion are located on the same side of the third positioning core head. The positioning protrusion is arc-shaped. The outer peripheral wall of the positioning protrusion is connected to one end of the lower flow channel body, and the inner peripheral wall of the positioning protrusion is in contact with the inner peripheral wall of the first positioning core head.

2. The inner cavity flow channel sand core according to claim 1, characterized in that: The first positioning core head includes a main body, a first arc-shaped connecting part, and a second arc-shaped connecting part. The main body is cylindrical. The first arc-shaped connecting part is arranged on the outer periphery of the main body and circumferentially arranged around the outer periphery of the main body. The inner peripheral wall of the positioning protrusion is in contact with the outer peripheral wall of the main body where the first arc-shaped connecting part is not arranged and the outer side wall of the first arc-shaped connecting part. The second arc-shaped connecting part is arranged on the side of the first arc-shaped connecting part away from the main body, and the second arc-shaped connecting part is connected to one end of the upper flow channel main body.

3. The inner cavity flow channel sand core according to claim 2, characterized in that: The positioning protrusion, the first arc-shaped connecting portion and the main body form a full circle.

4. The inner cavity flow channel sand core according to claim 1, characterized in that: The first positioning portion is a recessed structure recessed on the surface of the first positioning core head, and the third positioning portion protrudes from the surface of the third positioning core head; the second positioning portion protrudes from the surface of the second positioning core head, and the fourth positioning portion is a recessed structure recessed on the surface of the fourth positioning core head.

5. The inner cavity flow channel sand core according to claim 4, characterized in that: The cross section of the third positioning portion is circular, and the cross section of the second positioning portion is circular.

6. The inner cavity flow channel sand core according to claim 5, characterized in that: The diameter of the third positioning portion gradually decreases from close to the third positioning core head to away from the third positioning core head; and\or the diameter of the second positioning portion gradually decreases from close to the second positioning core head to away from the second positioning core head.

7. The inner cavity flow channel sand core according to claim 1, characterized in that: The third positioning core head is cylindrical, the third positioning portion is located in the middle of the third positioning core head, and the third positioning core head is concentrically arranged with the third positioning portion.

8. The inner cavity flow channel sand core according to claim 1, characterized in that: An upwardly recessed groove is provided on the lower side of the third positioning core head, and an annular positioning boss is provided on the lower side of the third positioning core head, and the annular positioning boss is arranged around the surface edge of the groove; the third positioning core head, the third positioning part, and the first positioning part are provided with interconnected through holes, and the through holes penetrate the groove.

9. The inner cavity flow channel sand core according to claim 1, characterized in that: The first positioning portion, the second positioning portion, the third positioning portion and the fourth positioning portion are each provided with one.

10. The inner cavity flow channel sand core according to claim 1, characterized in that: The upper flow channel body is provided with a first extension portion, the lower flow channel body is provided with a second extension portion, and an end of the first extension portion away from the upper flow channel body is opposite to an end of the second extension portion away from the lower flow channel body.

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