CN210139037U

CN210139037U - Salt core and piston

Info

Publication number: CN210139037U
Application number: CN201920760454.7U
Authority: CN
Inventors: 曾少波
Original assignee: Maller Automobile Technology (china) Co Ltd
Current assignee: Maller Automobile Technology (china) Co Ltd
Priority date: 2019-01-22
Filing date: 2019-05-24
Publication date: 2020-03-13
Anticipated expiration: 2029-05-24
Also published as: CN110076294A; CN109500361A

Abstract

The utility model provides a salt core and piston. The salt core is provided with an upper core surface covering the upper part of the salt core and a lower core surface covering the lower part of the salt core, the upper core surface and the lower core surface are in butt joint to form a mouth part of the salt core at the butt joint, and the maximum width of the upper core surface and the maximum width of the lower core surface are both larger than the width of the mouth part; at least one axial cross section of the upper core face has an upper core face profile with a first profile with a guide profile protruding towards the outer and/or inner underside of the salt core; the at least one axial cross-section of the lower core face has a lower core face profile having a second profile which tapers towards the mouth in extending from below upwards in the axial direction of the salt core. The internal cooling oil passage can be formed by the salt core. The oil forms strong vortex in last cavity, has longer contact time with the chamber wall in last cavity, and interior cold oil duct has better cooling effect.

Description

Salt core and piston

Technical Field

The utility model relates to a vehicle accessory field especially relates to a salt core and piston.

Background

In diesel or gasoline engines, the heat generated by the combustion process is very high and forced cooling of the piston is required. Usually, an internal cooling oil duct (also called an internal cooling oil chamber) is arranged inside the piston, and oil is filled into the internal cooling oil duct and vibrates in the internal cooling oil duct, so that the heat of the piston is taken away, and the temperature of the piston is reduced.

The forming method of the piston inner cooling oil passage comprises a press-fit method, a direct casting method, a water-soluble salt core method and the like, wherein the water-soluble salt core method is to use salt as a material to prepare a water-soluble salt core, and the salt core is placed into a mold for forming the piston during casting and is used as a core of the inner cooling oil passage. After the aluminum piston is cast, the salt core is punched out by high-pressure water, so that an inner cooling oil passage with the shape and the size consistent with those of the salt core is formed.

The inner cooling gallery is generally annular and formed at the top of the piston about the axis of the piston. The salt core as the core of the internal cooling oil passage is also annular.

As shown in fig. 11, in the internal cooling oil passage 9 formed by using a salt core with a conventional kidney-shaped cross section (axial cross section) as a core, oil is injected into the internal cooling oil passage 9 from below the piston and moves in the axial direction (C direction shown by an arrow) in the internal cooling oil passage 9, thereby cooling the top of the piston while oscillating in the internal cooling oil passage 9.

The cross-sectional shape of a common salt core may also be circular or racetrack.

SUMMERY OF THE UTILITY MODEL

The to-be-solved technical problem of the utility model is how to improve the cooling effect of interior cold oil duct to the piston.

In order to solve the technical problem, the utility model provides a salt core, which is annular, the outer surface of the salt core is a core surface, the core surface is provided with an upper core surface and a lower core surface which are mutually butted along the axial direction,

the upper core surface and the lower core surface form a mouth of the salt core at a butt joint, the mouth has a mouth width along a radial direction of the salt core, the upper core surface has an upper core surface maximum width along the radial direction of the salt core, the lower core surface has a lower core surface maximum width along the radial direction of the salt core, and the upper core surface maximum width and the lower core surface maximum width are both greater than the mouth width;

at least one axial cross-section of the upper core face has an upper core face profile with a first profile with an arcuate guide profile projecting radially outwardly of the salt core towards the outer underside of the salt core and/or an arcuate guide profile projecting radially inwardly of the salt core towards the inner underside of the salt core;

the at least one axial cross-section of the lower core face has a lower core face profile with a second profile on one radial side of the salt core, the second profile gradually sloping towards the mouth as it extends from bottom to top in the axial direction of the salt core.

In at least one embodiment, the second profile is linear, an extension of the second profile intersects the upper core face profile and forms an intersection point, and the first profile extends from the intersection point across the axially upper end of the salt core; or

The second profile is curvilinear, a tangent to an axially upper end of the second profile intersects the upper core face profile and forms an intersection, and the first profile extends from the intersection across the axially upper end of the salt core.

In at least one embodiment, the first profile is arcuate.

In at least one embodiment, the upper core face profile and the lower core face profile have a further profile in addition to the first profile and the second profile, which further profile smoothly transitions with the first profile and the second profile.

In at least one embodiment, the other profile is a smooth curve; or the other profile is a combination of smooth transitions of curves and straight lines.

In at least one embodiment, the second profile is linear and has an angle of 20 to 70 degrees with the axial direction; alternatively, the first and second electrodes may be,

the second profile is arcuate and a tangent at an upper end in an axial direction has an angle of 20 to 70 degrees with the axial direction.

In at least one embodiment, the second profile is located radially outward of the salt core.

In at least one embodiment, the guide profiles of the second and first profiles are located on the same radial side of the salt core; or the guide profiles of the second and first profiles are located on radially different sides of the salt core.

In at least one embodiment, the upper core face profile tapers in radial dimension extending in the axial direction from the location having the upper core face maximum width to the mouth, and the lower core face profile tapers in radial dimension extending in the axial direction from the location having the lower core face maximum width to the mouth.

In at least one embodiment, the upper core face profile further comprises a retarding profile connecting the axially lower ends of the guide profiles and extending to the mouth, the retarding profile extending in a radial direction of the salt core or forming an acute angle with the radial direction.

In at least one embodiment, the second profile and the guide profile are located on the same radial side of the salt core, the axially upper end of the second profile being located at the mouth, the retarding profile connecting the guide profile and the second profile.

In at least one embodiment, the hysteresis profile is linear and forms an angle with the radial direction of no greater than 30 degrees; alternatively, the first and second electrodes may be,

the retarding profile is arcuate and a tangent at an end adjacent the mouth forms an angle with the radial direction of no more than 30 degrees.

In at least one embodiment, the mouth width is 30% to 75% of the lower core face maximum width or the upper core face maximum width.

In at least one embodiment, the salt core has a salt core height between the axial ends, and the lower core face maximum width and/or the upper core face maximum width is between 50% and 100% of the salt core height.

In at least one embodiment, the upper core face maximum width is the same as the lower core face maximum width, or the upper core face maximum width is less than the lower core face maximum width.

The utility model also provides a piston, including annular interior cold oil duct, interior cold oil duct uses any one of above-mentioned embodiment salt core for the core and shaping.

The utility model also provides a piston, which comprises an annular inner cooling oil duct, wherein the inner cooling oil duct comprises an upper chamber and a lower chamber which are arranged along the axial direction of the piston, the upper chamber and the lower chamber are mutually butted and form an oil duct opening part at the butted part,

the upper chamber has an upper chamber maximum width in the radial direction of the piston, the lower chamber has a lower chamber maximum width in the radial direction of the piston, the oil passage port has a port width in the radial direction, and both the upper chamber maximum width and the lower chamber maximum width are greater than the port width;

at least one axial cross section of the upper chamber has an upper chamber contour having a first chamber contour with an arcuate guide cavity contour protruding radially outward of the inner cooling gallery toward an outer lower side of the inner cooling gallery and/or an arcuate guide cavity contour protruding radially inward of the inner cooling gallery toward an inner lower side of the inner cooling gallery; and is

The at least one axial cross section of the lower cavity has a lower cavity profile having a second cavity profile located on one side of the inner cooling oil gallery in the radial direction, the second cavity profile gradually inclining toward the oil gallery port in a process of extending from bottom to top in the axial direction of the inner cooling oil gallery;

the oil entering the inner cooling oil passage can flow into the upper chamber under the guiding action of the second chamber profile, and forms a vortex under the guiding action of the first chamber profile in the upper chamber.

In at least one embodiment, the second cavity contour is linear, an extension line of the second cavity contour intersects with the upper cavity contour and forms an intersection point, and the first cavity contour extends across the axial upper end of the internal cooling gallery from the intersection point; or

The second cavity contour is in a curve shape, a tangent line of the axial upper end of the second cavity contour intersects with the upper cavity contour to form an intersection point, and the first cavity contour crosses over the axial upper end of the inner cooling oil channel from the intersection point to extend.

In at least one embodiment, the first cavity profile is arcuate.

In at least one embodiment, the upper and lower chamber profiles have other cavity profiles in addition to the first and second cavity profiles, the other cavity profiles smoothly transitioning with the first and second cavity profiles.

In at least one embodiment, the other lumen profile is a smooth curve; or the other cavity profile is a combination of a smooth transition of a curved line and a straight line.

In at least one embodiment, the second cavity profile is linear and has an angle of 20 to 70 degrees with the axial direction; alternatively, the first and second electrodes may be,

the second chamber is curved in profile and a tangent at an upper end in an axial direction has an angle of 20 to 70 degrees with the axial direction.

In at least one embodiment, the second cavity profile is located radially outward of the inner cooling gallery.

In at least one embodiment, an extension of the second cavity profile passes through a combustion chamber throat of the piston.

In at least one embodiment, the guide cavity profiles of the second cavity profile and the first cavity profile are located on a same radial side of the inner cooling gallery; or the guide cavity profiles of the second cavity profile and the first cavity profile are positioned on different radial sides of the inner cooling oil channel.

In at least one embodiment, the upper chamber profile tapers in radial dimension extending in the axial direction from the location having the upper chamber maximum width toward the oil passage port, and the lower chamber profile tapers in radial dimension extending in the axial direction from the location having the lower chamber maximum width toward the oil passage port.

In at least one embodiment, the upper chamber profile further includes a stagnation chamber profile connecting an axially lower end of the guide chamber profile and extending to the oil passage port, the stagnation chamber profile extending in a radial direction of the inner cooling oil passage or forming an acute angle with the radial direction.

In at least one embodiment, the second cavity contour and the guide cavity contour are located on the same radial side of the internal cooling oil passage, the axially upper end of the second cavity contour is located at the oil passage opening, and the retardation cavity contour connects the guide cavity contour and the second cavity contour.

In at least one embodiment, the delay volume is linear in profile and forms an angle with the radial direction of no greater than 30 degrees; or the profile of the delay cavity is arc-shaped, and an included angle of not more than 30 degrees is formed between a tangent line at one end close to the oil passage opening part and the radial direction.

In at least one embodiment, the mouth width is 30% to 75% of the lower chamber maximum width or the upper chamber maximum width.

In at least one embodiment, the inner cooling gallery has an inner cooling gallery height between the axial ends, and the lower chamber maximum width and/or the upper chamber maximum width is between 50% and 100% of the inner cooling gallery height.

In at least one embodiment, the upper chamber maximum width is the same as the lower chamber maximum width, or the upper chamber maximum width is less than the lower chamber maximum width.

The utility model provides a salt core and piston have following beneficial effect at least:

the oil entering the inner cooling oil duct is guided for the first time by the cavity wall with the second cavity outline to reach the upper cavity and flows along the cavity wall with the upper cavity outline, the oil is guided for the second time by the cavity wall with the first cavity outline, the flow speed of the oil is increased when the oil passes through the oil duct opening in the process that the oil flows from the lower cavity to the upper cavity, so that a strong vortex is formed in the upper cavity, the oil has longer contact time with the cavity wall in the upper cavity, and the inner cooling oil duct has a better cooling effect.

The salt core has a shape which can form the inner cooling oil passage.

Drawings

Fig. 1 is a schematic perspective view showing the overall structure of one embodiment of the salt core provided by the present invention.

Fig. 2 is an axial cross-sectional view of the salt core of fig. 1.

Fig. 3 is a schematic diagram illustrating a cross-section on one axial side of a first embodiment of a salt core provided by the present invention, showing portions of the upper and lower core face profiles.

Fig. 4 is a schematic diagram showing a cross section of an inner cooling gallery of a piston core-formed with the salt core of fig. 3 on one axial side, showing a flow path of oil therein.

Fig. 5 is a schematic view showing a cross-section on one axial side of a second embodiment of the salt core provided by the present invention.

Fig. 6 is a schematic view showing a cross-section on one axial side of a third embodiment of the salt core provided by the present invention.

Fig. 7 is a schematic view showing a cross-section on one axial side of a fourth embodiment of the salt core provided by the present invention.

Fig. 8 is a schematic view showing a cross section of the inner cooling gallery cored with the salt core of fig. 7 on one axial side, showing a flow trace of oil therein.

Fig. 9 is a schematic view showing a cross-section on one axial side of a fifth embodiment of the salt core provided by the present invention.

Fig. 10 is a schematic view showing a cross section of the inner cooling gallery cored with the salt core of fig. 9 on one axial side, showing a flow trace of oil therein.

Fig. 11 is a schematic diagram showing a cross section of an inner cooling gallery of a piston core-formed with a conventional salt core on one axial side, showing a flow locus of oil therein.

Description of reference numerals:

9 an internal cooling oil duct;

1 salt core, 10 upper core face profile, 11 first profile, 11a guide profile, 13 third profile, 15 fifth profile, 20 lower core face profile, 22 second profile, 24 fourth profile, 26 sixth profile, 30 internal cooling gallery, 31 upper cavity, 110 first cavity profile, 110a guide cavity profile, 130 third cavity profile, 150 fifth cavity profile, 32 lower cavity, 220 second cavity profile, 240 fourth cavity profile, 260 sixth cavity profile, a mouth width, c upper core face maximum width, b lower core face maximum width, h salt core height, α second profile included angle with axial direction, β fifth profile included angle with radial direction.

Detailed Description

Reference will now be made in detail to the exemplary embodiments, examples of which are illustrated in the accompanying drawings. When the following description refers to the accompanying drawings, like numbers in different drawings represent the same or similar elements unless otherwise indicated. The implementations described in the exemplary embodiments below are not intended to represent all implementations consistent with the present disclosure. Rather, they are merely examples of apparatus and methods consistent with certain aspects of the present disclosure, as detailed in the appended claims.

The utility model provides a salt core and piston, this piston can use this salt core to be the core and the shaping of interior cold oil duct, also can have the interior cold oil duct that the profile is unanimous with the profile of salt core through other mode shaping.

As shown in fig. 1 and 2, the salt core 1 of the present invention is annular, and has an annular core body and an annular core surface surrounding the core body. In other words, the outer surface of the core is the core face.

The salt core 1 is used as a core of an inner cooling oil channel when the piston is formed, the shape of the inner cooling oil channel of the piston is the same as the outline shape of the salt core 1, and the position of each part of the inner cooling oil channel in the piston is the same as the position of the corresponding part of the salt core 1 in a piston mold.

Referring to fig. 3, it is defined herein that the "upper" portion of the salt core 1 forms a portion of the internal cooling oil passage near the top of the piston (i.e., an upper chamber), the "upper" portion of the salt core 1 is located at the "axially upper side" of the salt core 1, the "lower" portion of the salt core 1 forms a portion of the internal cooling oil passage near the bottom of the piston (i.e., a lower chamber), and the "lower" portion of the salt core 1 is located at the "axially lower side" of the salt core 1; also defined, the salt core 1 has an axial direction and a radial direction perpendicular to the axial direction, the annular core body and the core surface are formed around the axis of the salt core, the dimension of the salt core 1 in the radial direction is called the salt core width, and the dimension in the axial direction is called the salt core height; also defined, the side closer to the axis of the salt core 1 in the radial direction of the salt core 1 is called "radially inner side", and the side further from the axis of the salt core 1 in the radial direction of the salt core 1 is called "radially outer side".

As shown in fig. 3, the core surface has an upper core surface and a lower core surface arranged in the axial direction, and the upper core surface and the lower core surface extend from both ends in the axial direction in opposite directions in the axial direction, so that the upper core surface and the lower core surface cover the upper portion and the lower portion of the salt core 1, respectively. The salt core 1 has a cross-section (axial cross-section) in a plane through its axis, in which cross-section the upper and lower core faces have an upper core face profile 10 and a lower core face profile 20, respectively. The upper core surface and the lower core surface are butted in the extending process, and the salt core 1 is provided with a mouth part at the joint of the upper core surface and the lower core surface.

As shown in fig. 4, the internal cooling oil passage 30 formed by the salt core 1 has an upper chamber 31 and a lower chamber 32 arranged in the axial direction, the upper core surface profile is the same as the upper chamber profile of the upper chamber 31 of the internal cooling oil passage 30, the lower core surface profile is the same as the lower chamber profile of the lower chamber 32 of the internal cooling oil passage 30, and the upper chamber 31 and the lower chamber 32 form an oil passage opening at the joint.

The mouth of the salt core 1 has a mouth width a in the radial direction of the salt core, and the upper core surface profile 10 can have different widths in the process of extending in the axial direction and has an upper core surface maximum width c; the lower core face profile 20 may have a different width in the course of extending in the axial direction and a lower core face maximum width b. The maximum width c of the upper core surface and the maximum width b of the lower core surface are both larger than the width a of the mouth part.

The radial dimension of the upper core face profile 10 is tapered as the upper core face profile 10 extends axially towards the mouth from a position having an upper core face maximum width c. The radial dimension of the lower core face profile 20 tapers in the course of the lower core face profile 20 extending axially from a position having a lower core face maximum width b towards the mouth.

The dimensions of each part of the internal cooling oil passage 30 formed by the salt core 1 are the same as those of each corresponding part of the salt core 1.

When oil flows from bottom to top in the inner cooling oil passage 30, the oil firstly passes through the narrow oil passage opening part from the wide lower chamber 32 and then enters the wide upper chamber 31, and the flow rate of the oil is increased when the oil passes through the oil passage opening part.

When the oil liquid passes through the oil channel opening part and the oil channel opening part, the smooth flowing track is provided, so that the oil liquid is better guided.

The upper core face profile 10 has a first profile 11, the first profile 11 having at least an arcuate guide profile 11a which bulges towards the outer underside of the salt core 1 (see e.g. fig. 3) on the radially outer side of the salt core 1, or an arcuate guide profile 11a which bulges towards the inner underside of the salt core 1 (see e.g. fig. 7) on the radially inner side of the salt core 1.

The lower core face profile 20 has a second profile 22 extending linearly or curvilinearly between the two axial ends of the salt core 1, the second profile 22 gradually inclines towards the mouth in the process of extending from bottom to top in the axial direction of the salt core 1, and the second profile 22 points to the upper core face profile 10.

The upper chamber 31 of the internal cooling gallery 30 formed from the salt core 1 has a first cavity contour 110 corresponding to the first contour 11, and the lower chamber 32 of the internal cooling gallery 30 formed from the salt core 1 has a second cavity contour 220 corresponding to the second contour 22.

The first chamber contour 110 has a pilot chamber contour 110a corresponding to the pilot contour 11a, and the chamber wall having the pilot chamber contour 110a can guide the oil such that the oil forms a vortex in the upper chamber 31.

As shown in fig. 4, the oil entering the inner cooling gallery 30 is guided by the second cavity contour 220 of the inner cooling gallery 30 for the first time (as indicated by arrow a) to reach the upper cavity 30, the oil flows in the upper cavity 30 along the cavity wall having the upper cavity contour, and the oil is further guided by the cavity wall having the guide cavity contour 110a (corresponding to the guide contour 11a of the first cavity contour 110) for the second time (as indicated by arrow B) to be guided again to the upper cavity 31.

In this way, the oil forms strong vortex in the upper chamber 31, so that the oil has a longer contact time with the chamber wall in the upper chamber 31, and the inner cooling gallery 30 can better cool the piston.

In addition, since the lower chamber is contracted toward the port, the flow velocity of the oil increases while passing through the port in the process of flowing the oil from the lower chamber 32 to the upper chamber 31, thereby facilitating the formation of a stronger vortex in the upper chamber 31.

As shown in fig. 3 and 5, the upper core face maximum width c and the lower core face maximum width b may be the same (as shown in fig. 3) or different, and the upper core face maximum width c may be smaller than the lower core face maximum width b (as shown in fig. 5).

The second profile 22 is located on one radial side of the lower core face profile 20, and the guide profile 11a of the first profile 11 may be located on the same radial side of the salt core 1 as the second profile 22.

In this way, the upper and lower parts of the salt core 1 are formed substantially axially, thereby simplifying the process of manufacturing the salt core 1.

The profiles of the upper core surface profile 10 and the lower core surface profile 20 other than the first profile 11 and the second profile 22 are other profiles, and the other profiles, the first profile 11 and the second profile 22, may be connected in a smooth transition two by two. Other contours may be smooth curves, or a combination of smooth curves and straight lines.

The inner cooling gallery 30 has a further cavity contour corresponding to the further contour, and the further cavity contour, the first cavity contour 110 and the second cavity contour 220 may be connected in a smooth transition two by two.

As shown in fig. 3, 5, 6 and 9, the upper core face profile 10 and the lower core face profile 20 are straight (as shown in fig. 3, 5 and 9) or curved (as shown in fig. 6) on the other radial side of the salt core 1 (the side diametrically opposite the second profile 22), the straight extending profile being easier to machine than the circular extending profile.

As shown in fig. 3, 5, 6 and 9, the second profile 22 may be located radially outside the lower core profile 20 and the guide profile 11a may be located radially outside the upper core profile 10, i.e. the second profile 22 is located radially on the same side as the guide profile 11 a.

The second profile 22 may be rectilinear, with the extension of the second profile 22 intersecting the upper core face profile 10 and forming an intersection point which is radially inward of the upper core face profile 10, from which the first profile 11 extends across the axially upper end of the salt core 1.

As shown in fig. 10, the oil is guided by the second chamber profile 220 of the inner cooling gallery 30 for the first time (as indicated by arrow a) to the intersection point, and then is guided by the first chamber profile 110 for the second time (as indicated by arrow B), so that the oil is better guided and the directional vortex is better formed.

The first profile 11 may be formed in an arc shape, and the first profile 11 includes not only the guide profile 11a located at the radially outer side of the salt core 1 but also an arc-shaped profile located at the axially upper end of the salt core 1 and an arc-shaped profile located at the radially inner side of the salt core 1.

Accordingly, the first cavity contours 110 are also formed in an arc shape, and the first cavity contours 110 include not only the guide cavity contours 110a located radially outward of the internal cooling oil passage 301 but also an arc-shaped contour located at the axially upper end of the internal cooling oil passage 30 and an arc-shaped contour located radially inward of the internal cooling oil passage 30.

The curved profile can provide better guidance.

The curvature of the first profile 11 may be greater than 180 degrees, which is more favorable for forming directional vortices in the upper chamber 31 of the inner cooling gallery 30 formed thereby.

As shown in fig. 7, in other embodiments, the second profile 22 may also be located radially outside the lower core face profile 20, and the guiding profile 11a may be located radially inside the salt core 1, i.e. the second profile 22 and the guiding profile 11a are located on both sides in the radial direction.

As shown in fig. 8, in the internal cooling oil passage 30 formed by the salt core 1 in fig. 7, the oil is guided to the upper chamber 31 by the second chamber profile 220 located radially outward (as shown by arrow a in fig. 8), and is guided to form a vortex flow in the upper chamber 31 by the chamber wall having the guide chamber profile 110a (as shown by arrow B in fig. 8). The inner cooling oil passage can also obtain better cooling effect.

The second profile 22 may also be located radially inside the salt core 1, and an extension of the second profile 22 intersects the upper core face profile 10 and forms an intersection point which is located radially outside the upper core face profile 10, and the internal cooling oil passage 30 formed by such a salt core 1 also has a good cooling effect.

In other ways, the second profile 22 may also be curved, with a tangent to the axially upper end of the second profile 22 intersecting the upper core face profile 10 and forming a point of intersection, from which the first profile 11 is curved and extends across the axially upper end of the salt core 1.

As shown in fig. 3, the second profile 22 may have an acute included angle α with the axial direction of the salt core 1, for example, an included angle α of 20 to 70 degrees.

As shown in fig. 4, in the internal cooling gallery 30 formed by the salt core 1, the second cavity outline 220 guides the oil to the upper part inside the internal cooling gallery 30, so that the oil can intensively cool the periphery of the throat of the combustion chamber, which is beneficial to improving the cooling effect of the internal cooling gallery 30 on the piston.

As shown in fig. 3, 5, 6 and 9, the upper core profile 10 may also have a fifth profile 15 (stagnation profile), the axially upper end of the second profile 22 may be located at the mouth, the fifth profile 15 may extend in the radial direction or have a predetermined inclination with respect to the radial direction and connect the first profile 11 and the second profile 22.

As shown in fig. 4 and 10, the inner gallery 30 has a fifth cavity contour 150 conforming to the shape of the fifth contour 15, and the fifth cavity contour 150 delays oil guided by the first cavity contour 110 from exiting the upper chamber 31.

Thus, in the inner cooling gallery 30, the oil guided for the second time by the first chamber contour 110 is guided for the third time by the fifth chamber contour 150, and the residence time of the oil in the upper chamber 31 is extended.

In other embodiments, as shown in fig. 7, the fifth profile 15 may also be connected to the axially lower end of the first profile 11 above the mouth, instead of being connected between the second profile 22 and the first profile 11.

In order to form the above-mentioned inclination tendency, the fifth profile 15 may be straight and form an angle β not greater than 30 degrees with the radial direction, or the fifth profile 15 may be curved and a tangent line of an end of the fifth profile 15 connected to the second profile 12 forms an angle β not greater than 30 degrees with the radial direction.

It will be appreciated that the angle β between the fifth profile 15/fifth cavity profile 150 and the radial direction is positive when located above the upper end of the second profile 22/second cavity profile 220 and negative when located below the upper end of the second profile 22/second cavity profile 220.

The fifth chamber profile 150 provides better oil delay when the angle β is between 0 and 30 degrees, but may present some difficulty in machining, and provides more convenient machining but less delay when the angle β is between 0 and-30 degrees.

When the fifth profile 15 is linear, it is tangentially connected to the first profile 11 and transitionally connected to the second profile 22 in a circular arc shape, so that the problem of the strength reduction of the salt core 1 caused by the small size of the mouth can be effectively alleviated.

The mouth portion width a may be 30% to 75% of the maximum width b of the lower core surface.

In this way, in the internal cooling oil passage 30 formed by the salt core 1, both the strength of the salt core 1 and the oil guiding effect can be achieved.

The lower core face maximum width b and/or the upper core face maximum width c may be 50% to 100% of the salt core height h.

Thus, the salt core 1 can be ensured to have enough strength, and the flowing space of the oil and the guiding effect to the oil can be considered in the inner cooling oil passage 30 formed by the salt core 1.

Further details of the salt core 1 and the inner cooling oil passage 30 provided by the present invention will be described with reference to fig. 9 and 10.

In the cross section of the salt core 1, in a path from the radially outer side at the mouth portion to the radially outer side of the mouth portion through the upper core face profile 10, the radially inner side at the mouth portion, and the lower core face profile 20 in this order (clockwise path in fig. 9), the core face profiles have: a straight fifth contour 15, an arc-shaped first contour 11, a straight third contour 13, a straight fourth contour 24, a straight sixth contour 26, a straight second contour 22. The profiles are in arc transition at the joints, so that the joints are smooth and not sharp.

Both ends of the first profile 11 are located radially outside and radially inside the upper core surface profile 10, respectively, and the first profile 11 has a radially outermost side of the upper core surface profile 10 and a radially innermost side of the upper core surface profile 10. The first profile 11 is connected with the fifth profile 15 radially outside the salt core 1 and with the third profile 13 radially inside the salt core 1.

The third profile 13 and the fourth profile 24 each extend linearly in the axial direction of the salt core 1 and are connected radially inside the salt core 1.

The sixth profile 26 extends linearly in the radial direction of the salt core 1 and forms an annular plane perpendicular to the axial direction of the salt core 1.

The second profile 22 extends between a radially outer fifth profile 15 and a sixth profile 26 of the salt core 1, the second profile 22 forming an acute angle with the axial direction of the salt core 1, the second profile 22 gradually inclining inwards during the axial upward extension, so that the axially upper end of the second profile 22 is located radially inwards of the axially lower end.

The first profile 11 has an axially upper end of the upper core face profile 10, which axially upper end forms a salt core height h with the sixth profile 26.

When the piston is machined, the salt core 1 is installed in a piston mold, and after pouring, the salt core 1 is punched out to form the inner cooling oil channel 30 with the shape of an inner cavity consistent with the outline of a core surface. The salt core 1 part above the opening part forms an upper chamber 31 of the internal cooling oil channel 30, and the salt core 1 part below the opening part forms a lower chamber 32 of the internal cooling oil channel 30. The inner cooling gallery 30 has the same axial and radial directions as the salt core 1.

As shown in fig. 10, the inner cooling gallery 30 has, in addition to the first, second, and

fifth cavity contours

110, 220, 150, a third cavity contour 130 corresponding to the third contour 13, a fourth cavity contour 240 corresponding to the fourth contour 24, and a sixth cavity contour 260 corresponding to the sixth contour 26.

The lower end of the inner cooling gallery 30 has an oil inlet and an oil outlet spaced approximately 180 degrees apart, with oil entering the inner cooling gallery from the oil inlet and exiting the inner cooling gallery from the oil outlet, which may be disposed in a sixth cavity profile 260 corresponding to the sixth profile 26.

It will be appreciated that the salt core 1 may have the core face profile described above over the entire circumference, or over a portion of the circumference.

Accordingly, the oil may have the above-described flow pattern over the entire circumference of the inner cooling gallery 30, or may have the above-described flow pattern over a part of the circumference of the inner cooling gallery 30.

Other embodiments of the disclosure will be apparent to those skilled in the art from consideration of the specification and practice of the disclosure disclosed herein. This application is intended to cover any variations, uses, or adaptations of the disclosure following, in general, the principles of the disclosure and including such departures from the present disclosure as come within known or customary practice within the art to which the disclosure pertains. It is intended that the specification and examples be considered as exemplary only, with a true scope and spirit of the disclosure being indicated by the following claims.

It will be understood that the present disclosure is not limited to the precise arrangements described above and shown in the drawings and that various modifications and changes may be made without departing from the scope thereof. The scope of the present disclosure is limited only by the appended claims.

Claims

1. A salt core is annular, the outer surface of the salt core is a core surface, the core surface is provided with an upper core surface and a lower core surface which are mutually butted along the axial direction, the salt core is characterized in that,

2. The salt core of claim 1 wherein the second profile is linear, an extension of the second profile intersects the upper core face profile and forms an intersection, the first profile extends from the intersection across the axially upper end of the salt core; or

3. The salt core of claim 2 wherein the first profile is arcuate.

4. The salt core of claim 1 wherein the upper core face profile and the lower core face profile have a profile other than the first profile and the second profile, the other profile smoothly transitioning with the first profile and the second profile.

5. The salt core of claim 4 wherein the other profile is a smooth curve; or the other profile is a combination of smooth transitions of curves and straight lines.

6. The salt core of claim 1 wherein the second profile is linear and has an angle of 20 to 70 degrees from the axial direction; alternatively, the first and second electrodes may be,

7. The salt core of claim 1 wherein the second profile is radially outward of the salt core.

8. The salt core of claim 1 wherein the guide profiles of the second profile and the first profile are located on a radially same side of the salt core; or the guide profiles of the second and first profiles are located on radially different sides of the salt core.

9. The salt core of claim 1 wherein the radial dimension of the upper core face profile tapers in extending from the location having the upper core face maximum width in the axial direction toward the mouth, and wherein the radial dimension of the lower core face profile tapers in extending from the location having the lower core face maximum width in the axial direction toward the mouth.

10. The salt core of claim 1 wherein the upper core face profile further comprises a retarding profile connecting the axially lower end of the guide profile and extending to the mouth, the retarding profile extending in a radial direction of the salt core or forming an acute angle with the radial direction.

11. The salt core of claim 10 wherein the second profile and the guide profile are on the same radial side of the salt core, the axially upper end of the second profile being at the mouth, the retarding profile connecting the guide profile and the second profile.

12. The salt core of claim 10 wherein the hysteretic profile is linear and forms an angle with the radial direction of no more than 30 degrees; alternatively, the first and second electrodes may be,

13. The salt core of claim 1 wherein the mouth width is 30% to 75% of the lower core face maximum width or the upper core face maximum width.

14. Salt core according to claim 1, characterized in that the salt core has a salt core height between the axial ends, the lower core face maximum width and/or the upper core face maximum width being 50-100% of the salt core height.

15. The salt core of claim 1 wherein the upper core face maximum width is the same as the lower core face maximum width or the upper core face maximum width is less than the lower core face maximum width.

16. A piston comprising an annular inner cooling gallery, characterized in that the inner cooling gallery is shaped with a salt core as claimed in any one of claims 1 to 15 as a core.

17. A piston comprises an annular inner cooling oil channel, the inner cooling oil channel comprises an upper chamber and a lower chamber which are arranged along the axial direction of the piston, the upper chamber and the lower chamber are mutually butted and form an oil channel opening part at the butted part, and the piston is characterized in that,

18. The piston of claim 17 wherein said second chamber profile is linear, an extension of said second chamber profile intersects said upper chamber profile and forms an intersection, and said first chamber profile extends from said intersection across an axially upper end of said inner gallery; or

19. The piston of claim 18 wherein said first chamber profile is arcuate.

20. The piston of claim 17 wherein said upper and lower chamber profiles have other chamber profiles in addition to said first and second chamber profiles, said other chamber profiles smoothly transitioning with said first and second chamber profiles.

21. The piston of claim 20 wherein said other chamber profile is a smooth curve; or the other cavity profile is a combination of a smooth transition of a curved line and a straight line.

22. The piston of claim 17 wherein said second chamber is linear in profile and includes an angle of 20 to 70 degrees from said axial direction; alternatively, the first and second electrodes may be,

23. The piston of claim 17 wherein said second cavity contour is located radially outward of said inner gallery.

24. The piston of claim 17 wherein an extension of said second chamber profile passes through a combustion chamber throat of said piston.

25. The piston of claim 17 wherein said guide cavity contours of said second cavity contour and said first cavity contour are located on a radially same side of said inner gallery; or the guide cavity profiles of the second cavity profile and the first cavity profile are positioned on different radial sides of the inner cooling oil channel.

26. The piston of claim 17 wherein said upper chamber profile tapers in radial dimension extending in said axial direction from a location having said upper chamber maximum width toward said oil passage port, and wherein said lower chamber profile tapers in radial dimension extending in said axial direction from a location having said lower chamber maximum width toward said oil passage port.

27. The piston as set forth in claim 17 wherein said upper chamber profile further includes a stagnation chamber profile connecting an axially lower end of said guide chamber profile and extending to said oil passage port, said stagnation chamber profile extending in a radial direction of said inner cooling oil passage or forming an acute angle with said radial direction.

28. The piston as set forth in claim 27 wherein said second chamber contour and said guide chamber contour are located on a radially same side of said inner cooling gallery, an axially upper end of said second chamber contour is located at said gallery port, and said retard chamber contour connects said guide chamber contour and said second chamber contour.

29. The piston of claim 27 wherein said retardation chamber is linear in profile and forms an angle with said radial direction of no more than 30 degrees; or the profile of the delay cavity is arc-shaped, and an included angle of not more than 30 degrees is formed between a tangent line at one end close to the oil passage opening part and the radial direction.

30. The piston of claim 17 wherein said mouth width is 30% to 75% of said lower chamber maximum width or said upper chamber maximum width.

31. The piston of claim 17 wherein said inner gallery has an inner gallery height between said axial ends, and said lower chamber maximum width and/or said upper chamber maximum width is between 50% and 100% of said inner gallery height.

32. The piston of claim 17 wherein said upper chamber maximum width is the same as said lower chamber maximum width or said upper chamber maximum width is less than said lower chamber maximum width.