Patent Application
20210222264
The present invention relates to a mold that quenches a heated workpiece while pressing or restraining the same, a mold apparatus including the mold, and a cooling method for a workpiece using the mold.
In general, a mold that quenches a heated workpiece while pressing the same is known. Such a mold is disclosed in Japanese Patent Laid-Open No. 2005-169394, for example.
Japanese Patent Laid-Open No. 2005-169394 discloses a hot press apparatus that press-molds a heated metal plate material. In this hot press apparatus, an ejection hole through which a cooling medium such as water is ejected to a molding surface of a mold is provided in one of an upper mold and a lower mold, and a heated molded article that has been pressed is forcibly cooled in a pressed state with the cooling medium ejected through the ejection hole.
However, in the hot press apparatus disclosed in Japanese Patent Laid-Open No. 2005-169394, when the cooling medium is stored in a space in which the pressed molded article is placed, air is not discharged from the space in which the molded article is placed but remains therein such that the air may conceivably continue to contact the molded article. In this case, the cooling medium does not sufficiently cool a portion that the air contacts, and thus it becomes difficult to uniformly cool the molded article. When the heated molded article (workpiece) is not uniformly cooled, hardness difference or the like occurs in the molded article (workpiece).
The present invention has been proposed in order to solve the aforementioned problem, and an object of the present invention is to provide a mold capable of uniformly cooling a workpiece when cooling the heated workpiece while pressing or restraining the same, a mold apparatus including the mold, and a cooling method for a workpiece using the mold.
In order to attain the aforementioned object, a mold according to a first aspect of the present invention cools a heated workpiece while pressing or restraining the workpiece, and includes a lower mold in which a recess that stores a liquid coolant that cools the workpiece is provided on a molding surface and entirety of the workpiece is placed in an inner space of the recess and an upper mold in which a protrusion corresponding to the recess of the lower mold is provided on a molding surface. At least one of the lower mold and the upper mold includes a coolant supply passage through which the liquid coolant is supplied to the inner space of the recess, and the mold includes an air escape passage through which air in the inner space of the recess is discharged upward. In the present invention, the “molding surfaces” are surfaces that face each other in the upper mold and the lower mold, and are surfaces pressed or restrained in contact with the workpiece.
In the mold according to the first aspect of the present invention, as described above, the entirety of the workpiece is placed in the inner space of the recess of the lower mold, and the coolant supply passage through which the liquid coolant is supplied to the inner space of the recess is provided in at least one of the lower mold and the upper mold. Thus, the entirety of the workpiece can be reliably immersed in the liquid coolant, and contact of the air with the workpiece can be significantly reduced or prevented. Furthermore, the air escape passage through which the air in the inner space of the recess is discharged upward is provided in the mold such that the recess including the inner space in which the entirety of the workpiece in a pressed or restrained state is placed is filled with the liquid coolant, and thus the air in the inner space of the recess can be discharged upward through the air escape passage. Thus, supply of the liquid coolant to a surface of the workpiece is not hindered unlike the case where the air remains in the inner space of the recess. Consequently, the workpiece can be uniformly cooled when the heated workpiece is cooled in the pressed or restrained state.
A mold apparatus according to a second aspect of the present invention includes the mold according to the first aspect, a pump that supplies the liquid coolant to the coolant supply passage of the mold, and a controller that controls the pump to supply the liquid coolant.
The mold apparatus according to the second aspect of the present invention includes the mold according to the first aspect such that similarly to the first aspect, the workpiece can be uniformly cooled when the heated workpiece is cooled in a pressed or restrained state. Furthermore, liquid coolant supply is controlled by the controller such that liquid coolant flow in the recess can be adjusted while the air in the inner space of the recess is discharged upward through the air escape passage. Thus, the workpiece can be reliably cooled with the liquid coolant.
A cooling method for a workpiece according to a third aspect of the present invention includes placing entirety of the workpiece in an inner space of a recess provided on a molding surface of a lower mold, pressing or restraining the workpiece by a mold including the lower mold and an upper mold in which a protrusion corresponding to the recess of the lower mold is provided on a molding surface, supplying a liquid coolant to the inner space of the recess through a coolant supply passage provided in at least one of the lower mold and the upper mold by a pump and discharging air in the inner space of the recess upward through an air escape passage, and cooling the workpiece by immersing the entirety of the workpiece, which has been heated, in the liquid coolant that fills the recess. It should be noted that the order of a step of “placing the entirety of the workpiece in the inner space of the recess provided on the molding surface of the lower mold”, a step of “pressing or restraining the workpiece by the mold including the lower mold and the upper mold in which the protrusion corresponding to the recess of the lower mold is provided on the molding surface”, and a step of “supplying the liquid coolant to the inner space of the recess through the coolant supply passage provided in at least one of the lower mold and the upper mold by the pump and discharging the air in the inner space of the recess upward through the air escape passage” is not particularly limited to the above-described order. Furthermore, in the step of “pressing or restraining the workpiece by the mold”, the mold may not press or restrain a portion that does not need to be deformed or a portion that does not need to be restrained. That is, it is not necessary for the mold to press or restrain the entirety of the workpiece, and the mold may press or restrain only a portion of the workpiece.
In the cooling method for the workpiece according to the third aspect of the present invention, the liquid coolant is supplied to the inner space of the recess through the coolant supply passage provided in at least one of the lower mold and the upper mold by the pump, the air in the inner space of the recess is discharged upward through the air escape passage, and the workpiece is cooled by immersing the entirety of the heated workpiece in the liquid coolant that fills the recess. Thus, similarly to the first aspect, the workpiece can be uniformly cooled when the heated workpiece is cooled in a pressed or restrained state. Furthermore, the liquid coolant is supplied to the inner space of the recess by the pump such that the air in the inner space can be discharged, and the flow rate of the liquid coolant can be controlled. Thus, the workpiece can be more effectively cooled.
According to the present invention, as described above, the mold capable of uniformly cooling the workpiece when cooling the heated workpiece while pressing or restraining the same, the mold apparatus including the mold, and the cooling method for the workpiece using the mold can be provided.
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Embodiments of the present invention are hereinafter described.
The structure of a mold apparatus 100 according to a first embodiment of the present invention is now described with reference to
(Structure of Mold Apparatus)
As shown in
The workpiece W is a rectangular plate member elongated in a direction X, as planarly viewed, and is preformed into a predetermined flat plate shape. The thickness of the workpiece W in an upward-downward direction (direction Z) is t (see
The workpiece W is made of a steel plate such as an Al-plated steel plate, a Zn-plated steel plate, a high-strength steel plate, or ordinary steel. The workpiece W is heated to a temperature higher than a martensite transformation temperature (a lowest temperature at which martensitic transformation can occur) in advance by high-frequency heating, induction heating, electrical heating, heating in a furnace, or the like so as to be conveyed in an austenitized state to the mold apparatus 100.
As shown in
As shown in
According to the first embodiment, as shown in
As shown in
As shown in
As shown in
As shown in
As shown in
The lower mold 10 includes a plurality of discharge groove collection passages 15 through which the water is collected from the discharge groove 14. The plurality of discharge groove collection passages 15 include openings 15a provided in the bottom surface 14a of the discharge groove 14 and first discharge groove collection passages 15b that respectively extend downward from a plurality of openings 15a and connected to the second lower mold collection passages 13c of the lower mold collection passages 13. Consequently, some of the water supplied to the inner space S of the recess 11 is discharged by the discharge groove 14 and the discharge groove collection passages 15.
A frame-like sealing member 16 that surrounds the entire circumference of the discharge groove 14 is disposed in the vicinity of the outer end of the lower mold 10, which is the outside of the discharge groove 14. The sealing member 16 comes into contact with the lower surface 20a of the upper mold 20 in a state where the lower mold 10 and the upper mold 20 restrain the workpiece W such that the water does not leak from a space between the lower mold 10 and the upper mold 20 including the inner space S of the recess 11.
As shown in
As shown in
According to the first embodiment, the upper mold collection passages 23 are provided above the workpiece W, and thus in the mold 1, the air can be discharged upward through the upper mold collection passages 23.
As shown in
The upper mold 20 includes a plurality of upper mold collection passages 24 corresponding to the plurality of discharge groove collection passages 15. The plurality of upper mold collection passages 24 include openings 24a provided in the lower surface 20a of the upper mold 20 and first collection passages 24b that respectively extend upward from a plurality of openings 24a and connected to the second upper mold collection passages 23c of the upper mold collection passages 23.
The second supply passages 22c and the second upper mold collection passages 23c are respectively connected to the supply connectors 30 and the collection connectors 40 on the outer surface 20b of the upper mold 20. Thus, similarly to the lower mold 10, in the second mold 20, water is ejected and supplied to the inner space S of the recess 11 through the supply tubes 6, the supply connectors 30, and the water supply passages 22. Furthermore, the water and air in the inner space S of the recess 11 are collected outside of the mold 1 through the upper mold collection passages 23, the collection connectors 40, and the suction tubes 7.
According to the first embodiment, as shown in
As shown in
(Cooling of Workpiece Using Mold Apparatus)
A cooling method for the workpiece W using the mold apparatus 100 according to the first embodiment of the present invention is now described with reference to
First, the workpiece W is heated to a temperature higher than the martensite transformation temperature (or bainite transformation temperature) by a heater (not shown) so as to have an austenite structure. As shown in
Thereafter, the upper mold 20 is moved downward such that as shown in
Thus, the water is ejected to the workpiece W through the water supply passages 12 of the lower mold 10 and the water supply passages 22 of the upper mold 20, and is supplied to the inner space S of the recess 11. At this time, the water and air move through flow paths provided between the minute protrusions 1d between the workpiece W and the lower mold 10 and between the workpiece W and the upper mold 20. Consequently, as shown in
At the predetermined timing, the suction pump 3 is driven by the controller 4. Thus, the air that has moved to the upper mold collection passages 23 of the upper mold 20 is collected together with the water in the suction pump 3. The air that has moved to the passage 1c is collected together with the water in the suction pump 3 through the discharge groove collection passages 15 of the lower mold 10 and the upper mold collection passages 24 of the upper mold 20. Depending on the drive timing of the suction pump 3, some of the air is collected together with the water in the suction pump 3 through the lower mold collection passages 13 of the lower mold 10. Then, the air is discharged from the inner space S of the recess 11 such that the inner space S of the recess 11 is filled with the water. The space between the lower mold 10 and the upper mold 20 surrounded by the sealing member 16 becomes closed such that water leakage is significantly reduced or prevented, and thus even water flow (laminar flow) can be easily created by appropriate water supply control and water collection control of the controller 4.
According to the first embodiment, retention of the air in the inner space S of the recess 11 is significantly reduced or prevented, and thus the sealing performance of the mold 1 is not required functionally. Thus, in the mold 1, the water may leak somewhat to the outside beyond the sealing member 16. Consequently, both the complicated seal structure of the mold 1 due to strict seal securement and the increased cost of providing the complicated seal structure in the mold can be significantly reduced or prevented.
Consequently, in the inner space S of the recess 11, the water is supplied to a surface of the workpiece W pressed or restrained by the mold 1 without being hindered by the air. Thus, the entirety of the workpiece W is immersed in the water so as to be rapidly cooled substantially uniformly. That is, the workpiece W is quenched. Thus, the strength (hardness) of the workpiece W is substantially uniformly improved while deformation of the workpiece W due to the rapid cooling is significantly reduced or prevented.
After cooling of the workpiece W is completed, the water in the closed space between the lower mold 10 and the upper mold 20 is discharged through the lower mold collection passages 13 and the discharge groove collection passages 15 of the lower mold 10. The workpiece W is cooled with the water, and thus the cooling time of the workpiece W is about several seconds. Finally, the upper mold 20 is moved upward, and the quenched workpiece W is taken out from the mold 1.
According to the first embodiment, the following effects are achieved.
According to the first embodiment, as described above, the entirety of the workpiece W is placed in the inner space S of the recess 11 of the lower mold 10, and the water supply passages 12 and 22 through which the water is supplied to the inner space S of the recess 11 are provided in the lower mold 10 and the upper mold 20. Thus, the entirety of the workpiece W can be reliably immersed in the water, and contact of the air with the workpiece W can be significantly reduced or prevented. Furthermore, the passage 1c and the upper mold collection passages 23 through which the air in the inner space S of the recess 11 is discharged upward are provided in the mold 1 such that the recess 11 including the inner space S in which the entirety of the workpiece W in the pressed or restrained state is placed is filled with the water, and thus the air in the inner space S of the recess 11 can be discharged upward through the passage 1c and the upper mold collection passages 23. Thus, supply of the water to the surface of the workpiece W is not hindered unlike the case where the air remains in the inner space S of the recess 11. Consequently, the workpiece W can be uniformly cooled when the heated workpiece W is cooled in the pressed or restrained state. In addition, the air that has moved to the upper mold collection passages 23 of the upper mold 20 is collected together with the water in the suction pump 3, and the air that has moved to the passage 1c is collected together with the water in the suction pump 3 through the discharge groove collection passages 15 of the lower mold 10 and the upper mold collection passages 24 of the upper mold 20. Thus, movement (return) of the air to the inner space S can be reliably significantly reduced or prevented.
According to the first embodiment, as described above, the passage 1c is provided between the lower mold 10 and the upper mold 20 such that the passage 1c through which the air can be discharged upward in a state where the workpiece W is pressed or restrained by the lower mold 10 and the upper mold 20 can be easily provided in the mold 1.
According to the first embodiment, as described above, the upper mold collection passages 23 are provided in the protrusion 21 of the upper mold 20 such that even when the air moves upward in the inner space S of the recess 11 and remains between the upper mold 20 and the workpiece W, the air that remains in the inner space S can be discharged from the inner space S of the recess 11 through the upper mold collection passages 23 provided in the protrusion 21 of the upper mold 20.
According to the first embodiment, as described above, the passage 1c is provided between the inner surface 11b of the recess 11 of the lower mold 10 and the outer surface 21b of the protrusion 21 of the upper mold 20. Thus, the passage 1c through which the air can be discharged upward can be easily provided in the mold 1.
According to the first embodiment, as described above, the upper mold collection passages 23 includes the first upper mold collection passages 23b that extend upward from the molding surface F2 of the protrusion 21 and the second upper mold collection passages 23b connected to the first upper mold collection passages 23b and that extend in the horizontal direction to the outer surface 20b the upper mold 20. Thus, the air that remains between the upper mold 20 and the workpiece W can easily move upward through the first upper mold collection passages 23b.
According to the first embodiment, as described above, in the lower mold 10, the openings 13a of the lower mold collection passages 13 are provided outside the openings 12a of the water supply passages 12. In addition, in the upper mold 20, the openings 23a of the upper mold collection passages 23 are provided outside the openings 22a of the water supply passages 22. Thus, the water in the inner space S of the recess 11 can be collected through the openings 13a and 23a provided outside the openings 12a and 22a while the water is supplied into the inner space S of the recess 11 through the openings 12a and 22a. Thus, flow from the inside to the outside can be easily created, and thus even water flow (laminar flow) is easily created in the inner space S of the recess 11 such that retention of the water in the inner space S can be significantly reduced or prevented.
According to the first embodiment, as described above, the plurality of water supply passages 12 and 22 are respectively provided in the lower mold 10 and the upper mold 20 such that the water can be widely and quickly supplied to the inner space S of the recess 11. Furthermore, the water supply passages 12 and 22 are respectively provided in the lower mold 10 and the upper mold 20 such that unlike the case where the water supply passages are provided only in one of the lower mold 10 and the upper mold 20, the water can be substantially uniformly brought into contact with the upper surface and the lower surface of the workpiece W, and thus the entirety of the workpiece W can be rapidly cooled more uniformly.
According to the first embodiment, the openings 12a of the plurality of water supply passages 12 are dispersedly provided in the region of the recess 11 in which the workpiece W is placed in a planar view. Furthermore, the openings 22a of the plurality of water supply passages 22 are dispersedly provided in the region in which the workpiece W is placed in a planar view. Thus, the water can be more widely and more quickly supplied to the inner space S of the recess 11.
According to the first embodiment, as described above, the circumferential discharge groove 14 that surrounds the entire circumference of the recess 11 is provided outside the recess 11 of the lower mold 10. Thus, excessive water supplied to the inner space S of the recess 11 can be temporarily stored in the discharge groove 14, and thus water leakage from the mold 1 can be significantly reduced or prevented. Consequently, water flow in the inner space S of the recess 11 can be more easily controlled.
According to the first embodiment, as described above, the discharge groove collection passages 15 through which the water in the discharge groove 14 is collected is provided in the lower mold 10 such that continuous storing of the water in the discharge groove 14 can be significantly reduced or prevented, and thus water flow in the inner space S of the recess 11 can be reliably controlled.
According to the first embodiment, as described above, the sealing member 16 is disposed outside the recess 11 in the lower mold 10 such that the inner space S of the recess 11 can be closed, and thus water flow in the inner space S of the recess 11 can be reliably controlled while water leakage to the outside is significantly reduced or prevented.
According to the first embodiment, as described above, water supply is controlled by the controller 4 such that water flow in the recess 11 can be adjusted while the air in the inner space S of the recess 11 is discharged upward through the passage 1c and the upper mold collection passages 23. Thus, the workpiece W can be reliably cooled with the water.
According to the first embodiment, as described above, the water is supplied to the inner space S of the recess 11 by the supply pump 2 through the water supply passages 12 provided in the lower mold 10 and the water supply passages 22 provided in the upper mold 20, the air in the inner space S of the recess 11 is discharged upward through the passage 1c and the upper mold collection passages 23, and the entirety of the heated workpiece W is immersed in the water that fills the recess 11 so as to be cooled. Thus, the workpiece W can be uniformly cooled.
According to the first embodiment, as described above, the water is supplied to the inner space S of the recess 11 by the supply pump 2 such that the air in the inner space S can be discharged, and the flow rate of the water can be controlled. Thus, the workpiece W can be more effectively cooled.
The structure of a mold apparatus 200 according to a second embodiment of the present invention is now described with reference to
(Structure of Mold Apparatus)
As shown in
As shown in
According to the second embodiment, as shown in FIG. 14, in the lower mold 110, openings 112a (portions shown by black circles) of the water supply passages 112 and openings 113a (portions shown by white circles) of the lower mold collection passages 113 are alternately provided in the bottom surface 11a of the recess 11, as planarly viewed from above. Specifically, the openings 112a and the openings 113a are alternately disposed in a direction X in a region (molding surface F1) that overlaps with the workpiece W. Furthermore, the openings 112a and the openings 113a are alternately disposed in the direction X and a direction Y outside the region that overlaps with the workpiece W.
Similarly, as shown in
According to the second embodiment, the following effects are achieved.
According to the second embodiment, as described above, the recess 11 of the lower mold 110 includes the inner space S in which the entirety of the workpiece W is placed. Furthermore, the water supply passages 112 and 122 through which the water is supplied to the inner space S of the recess 11 are provided in the lower mold 110 and the upper mold 120. In addition, a passage 1c and the upper mold collection passages 123 through which the air in the inner space S of the recess 11 is discharged upward are provided in the mold 101. Thus, similarly to the first embodiment, the workpiece W can be uniformly cooled when the heated workpiece W is cooled in a pressed or restrained state.
According to the second embodiment, as described above, in the lower mold 110, the openings 112a of the water supply passages 112 and the openings 113a of the lower mold collection passages 113 are alternately provided in the bottom surface 11a of the recess 11, as planarly viewed from above (in a planar view). Furthermore, in the upper mold 120, the openings 122a of the water supply passages 122 and the openings 123a of the upper mold collection passages 123 are alternately provided in the protruding surface 21a of the protrusion 21, as planarly viewed from below (in a planar view). Thus, before the air pushed out by the water supplied through the water supply passages 112 and 122 remains in the inner space S of the recess 11 for a long time, the air can be promptly collected through the lower mold collection passages 113 and the upper mold collection passages 123 nearby located. Thus, the workpiece W can be more uniformly cooled. Furthermore, the openings 112a and 122a through which the water is supplied and the openings 113a and 123a through which the water is collected are alternately disposed such that the flow rate of the water can be more uniform. Thus, water flow in the inner space S of the recess 11 can be more easily controlled. The remaining effects of the second embodiment are similar to those of the first embodiment, and thus description thereof is omitted.
The structure of a mold apparatus 300 according to a third embodiment of the present invention is now described with reference to
(Structure of Mold Apparatus)
The workpiece W1 to be quenched by the mold apparatus 300 according to the third embodiment is formed into a box shape, as shown in
As shown in
As shown in
According to the third embodiment, as shown in
Similarly, as shown in
According to the third embodiment, a discharge groove is not provided in the lower mold 210, unlike the first embodiment. The lower mold 210 includes lower mold collection passages 217 through which water and air that have passed through a passage 1c and moved to the outside are collected. The remaining structures of the mold apparatus 300 according to the third embodiment and a cooling method for the workpiece W1 using the mold apparatus 300 are similar to those according to the first embodiment, and thus description thereof is omitted.
According to the third embodiment, the following effects are achieved.
According to the third embodiment, as described above, the recess 11 of the lower mold 210 includes the inner space S in which the entirety of the workpiece W1 having a box shape is placed. Furthermore, the water supply passages 212 and 222 through which the water is supplied to the inner space S of the recess 11 are provided in the lower mold 210 and the upper mold 220. In addition, the passage 1c and the upper mold collection passages 223 through which the air in the inner space S of the recess 11 is discharged upward are provided in the mold 201. Thus, the workpiece W1 having a box shape can be uniformly cooled when the heated workpiece W1 is cooled in a pressed or restrained state. The remaining effects of the third embodiment are similar to those according to the first embodiment and the second embodiment, and thus description thereof is omitted.
The embodiments disclosed this time must be considered as illustrative in all points and not restrictive. The range of the present invention is not shown by the above description of the embodiments but by the scope of claims for patent, and all modifications (modified examples) within the meaning and range equivalent to the scope of claims for patent are further included.
For example, while the example in which the discharge groove 14 and the discharge groove collection passages 15 are provided in the lower mold 10, and the sealing member 16 is disposed in the lower mold 10 has been shown in the aforementioned first embodiment, the present invention is not restricted to this. According to the present invention, the discharge groove, the discharge groove collection passages, and the sealing member may not be provided as in a lower mold 310 according to a modified example of the first embodiment in
In the lower mold, the positions of the openings of the water supply passages and the positions of the openings of the lower mold collection passages are not particularly limited to the structures of the lower molds according to the aforementioned first to third embodiments. For example, as in the lower mold 310 according to the modified example of the first embodiment in
While the example in which the passage 1c and the upper mold collection passages 23 (123, 223) are provided as the “air escape passage” in the claims in the mold 1 (101, 201) has been shown in each of the aforementioned first to third embodiments, the present invention is not restricted to this. According to the present invention, for example, the collection passages through which the air in the inner space of the recess is discharged upward may not be provided in the mold, and the air in the inner space of the recess may be discharged upward only through the passage (air escape passage) provided between the inner surface of the recess of the lower mold and the outer surface of the protrusion of the upper mold. In this case, the mold is preferably small, and the shape of the mold (the shape of the workpiece) is preferably not complicated because the air can be efficiently discharged upward through the passage.
While the example in which the workpiece W formed into a flat plate shape is used has been shown in each of the aforementioned first and second embodiments, and the example in which the workpiece W1 formed into a box shape is used has been shown in the aforementioned third embodiment, the present invention is not restricted to this. According to the present invention, the shape of the workpiece is not particularly limited as long as the workpiece can be placed in the inner space of the recess of the lower mold. In order to press or restrain the workpiece, it is necessary to match the shape of the molding surface of the mold to the shape of the workpiece. However, the shape of the entire molding surface of the mold may not be matched to the shape of the workpiece. That is, it is only necessary to match the shape of a portion of the molding surface of the mold that contributes to pressing or restraining to the shape of the workpiece.
For example, when a workpiece W2 has a stepped shape (drawing shape) in a sectional view as in a mold 401 shown in a modified example of the third embodiment shown in
While the example in which the sealing member 16 is disposed in the vicinity of the outer end of the lower mold 10 (110, 210) has been shown in each of the aforementioned first to third embodiments, the present invention is not restricted to this. According to the present invention, the sealing member may not be disposed in the vicinity of the outer end of the lower mold but may be disposed on the outside of the recess and the inside of the lower mold in the vicinity of the recess.
While the example in which the water supply passages (112, 212) and 22 (122, 222) are provided in the region of the recess 11 in which the workpiece W (W1) is placed has been shown in each of the aforementioned first to third embodiments, the present invention is not restricted to this. According to the present invention, as long as the coolant can be supplied to the inner space of the recess, the coolant supply passages may be provided outside the region of the recess in which the workpiece is placed.
While the example in which the plurality of water supply passages and collection passages are provided in both the lower mold and the upper mold has been shown in each of the aforementioned first to third embodiments, the present invention is not restricted to this. According to the present invention, the water supply passages and the collection passages may be provided in only one of the lower mold and the upper mold. Furthermore, the number of water supply passages, the number of collection passages, the positions of the water supply passages, and the positions of the collection passages are not particularly limited. Incidentally, the number of water supply passages, the number of collection passages, the size (hole diameter) of the water supply passages, and the size (hole diameter) of the collection passages are preferably appropriately adjusted according to the shape and size of the workpiece. In this case, the number of water supply passages, the number of collection passages, the size of the water supply passages, and the size of the collection passages are preferably adjusted such that the flow rate of the liquid coolant to be collected becomes smaller than the flow rate of the liquid coolant to be supplied.
While the example in which water is used as the “liquid coolant” in the claims has been shown in each of the aforementioned first to third embodiments, the present invention is not restricted to this. According to the present invention, in addition to water, one or a combination of polyhydric alcohols, aqueous solutions of polyhydric alcohols, polyglycol, mineral oil, synthetic ester, silicone oil, fluorine oil, grease, water emulsion, etc. may be used as the liquid coolant. It should be noted that the present invention is particularly suitable for a mold apparatus using a liquid coolant having a low temperature and a high cooling performance.
While the example in which the mold according to the present invention is provided in the so-called press quench apparatus as the mold apparatus 100 (200, 300) has been shown in each of the aforementioned first to third embodiments, the present invention is not restricted to this. According to the present invention, the mold according to the present invention may be used for a mold apparatus other than the press quench apparatus. For example, the mold according to the present invention may be used for a so-called pot press (hot press) apparatus in which a heated workpiece is press-molded into a predetermined shape, and the workpiece is cooled in a pressed state with a liquid coolant.
While the example in which the workpiece W (W1) is made of a steel plate such as an Al-plated steel plate, a Zn-plated steel plate, a high-strength steel plate, or ordinary steel has been shown in each of the aforementioned first to third embodiments, the present invention is not restricted to this. According to the present invention, a material for the workpiece is not particularly limited.
While the example in which the mold apparatus 100 (200, 300) includes the suction pump 3 has been shown in each of the aforementioned first to third embodiments, the present invention is not restricted to this. According to the present invention, the air may be discharged upward through the air escape passage at atmospheric pressure without providing the suction pump in the mold apparatus. In this case, in order to reliably discharge the air upward through the air escape passage, the air escape passage is preferably provided above a position in the recess at which the air is likely to remain when the shape of the mold is complicated, for example.
As in a mold apparatus 500 according to a modified example shown in
While the example in which the plurality of minute protrusions 1d are provided at the predetermined intervals on the substantially entire bottom surface 11a of the recess 11 and the substantially entire protruding surface 21a of the protrusion 21 that contact the workpiece W (W1) such that the water and air move through the flow paths provided between the minute protrusions 1d has been shown in each of the aforementioned first to third embodiments, the present invention is not restricted to this. For example, a plurality of grooves through which water and air can move may be provided in a portion of the mold that the workpiece W contacts.
While the example in which after the heated workpiece W is placed in the inner space S of the recess 11 and is sandwiched between the lower mold 10 and the upper mold 20, the water is supplied to the inner space S of the recess 11, the air is discharged upward from the inner space S of the recess 11, and the entirety of the workpiece W is immersed in the water so as to be cooled has been shown in each of the aforementioned first to third embodiments, the present invention is not restricted to this. According to the present invention, for example, after the water is supplied in advance to the inner space of the recess and the air is discharged upward from the inner space of the recess, the heated workpiece may be placed (immersed) in the flooded inner space of the recess, and the workpiece may be sandwiched between the lower mold and the upper mold and be cooled. In this case, the workpiece may be sandwiched between the lower mold and the upper mold after the workpiece is placed (immersed) in advance in the inner space of the recess. Alternatively, the upper mold and the workpiece may be moved together such that the workpiece is placed (immersed) in the inner space of the recess substantially at the same time as sandwiching the workpiece between the lower mold and the upper mold.
In each of the aforementioned first to third embodiments, a lifter that lifts the workpiece upward may be added to the lower mold in order to minimize contact between the workpiece and the mold. The upper mold is moved downward such that the lifter is housed in the lower mold. Thus, contact of the workpiece with the lower mold (mold) is significantly reduced or prevented except for a state where the workpiece is pressed or restrained by the mold.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2016-086983 | Apr 2016 | JP | national |
This application is a Divisional of U.S. application Ser. No. 16/095,109 filed Oct. 19, 2018, which is the National Stage of PCT/JP2017/015536 filed Apr. 18, 2017, and claims the benefit of JP2016-086983 filed Apr. 25, 2016, the entire content of each of which is incorporated by reference herein.
| Number | Date | Country | |
|---|---|---|---|
| Parent | 16095109 | Oct 2018 | US |
| Child | 17225287 | US |
