CN109702130B - Forging mold - Google Patents
Forging mold Download PDFInfo
- Publication number
- CN109702130B CN109702130B CN201811255986.1A CN201811255986A CN109702130B CN 109702130 B CN109702130 B CN 109702130B CN 201811255986 A CN201811255986 A CN 201811255986A CN 109702130 B CN109702130 B CN 109702130B
- Authority
- CN
- China
- Prior art keywords
- space
- die
- pulley
- forging
- parking gear
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Abstract
A forging die, in a step of molding a pulley shaft of a continuously variable transmission in which a shaft portion, a conical pulley portion, and a parking gear disposed on the back side of the conical pulley portion are integrally produced by forging, fills the tip portion of the parking gear with a material. A relief space (120) extending outward in the radial direction of a pulley part and allowing burrs to flow out is provided in a mold (100) composed of upper and lower molds (104, 106), the relief space (120) has a first space formed radially outward of the tooth top of a parking gear and a second space formed radially outward of the tooth bottom of the parking gear, and the flow resistance of the burrs in the first space is set to be larger than the flow resistance of the burrs in the second space.
Description
Technical Field
The present invention relates to a forging die for manufacturing a pulley shaft that constitutes a fixed pulley of a belt type continuously variable transmission (hereinafter referred to as CVT), and more particularly to a forging die suitable for manufacturing a pulley shaft in which a parking gear having a slightly smaller diameter than the outer diameter of a pulley is integrally formed with a pulley on the back surface of the pulley (the surface opposite to the pulley surface).
Background
A CVT mounted in a vehicle needs to be provided with a parking mechanism, but a known CVT has a parking gear constituting the parking mechanism integrally attached to the rear surface side of a pulley surface of a fixed pulley (pulley shaft) (patent document 1).
Patent document 1: japanese unexamined patent publication No. 11-254084
In the case of manufacturing the above-described pulley shaft by forging, a steel material having a silicon (Si) content of about 0.2 mass% is generally used, but in this case, in order to improve the durability of the pulley surface, it is necessary to perform a micro shot blasting treatment in a post-process. However, when the shot used for the micro shot peening is not completely removed but remains in a small amount, the shot becomes an inclusion (contaminant), and a problem such as oil vibration occurs in the CVT as a product.
Therefore, in recent years, it has been studied to use high Si steel having a silicon content of 0.8 to 1.0 mass% as a material for improving the durability of a pulley shaft (particularly, a pulley surface) and for eliminating a micro shot blasting step.
Since the above high-Si steel generates scale with high hardness when subjected to normal hot forging (heating temperature of about 1250 ℃), and abrasion of the die progresses in a short time, the applicant has found that, in order to suppress the generation of scale with high hardness and ensure the life of the die, it is necessary to produce the die by sub-hot forging (heating temperature of 1120 to 1160 ℃) at a lower heating temperature than normal.
However, in the case of the sub-hot forging, the hardness of the workpiece is not sufficiently reduced by heating, and the fluidity of the material in the mold is reduced, so that the material cannot spread over the entire mold, and in particular, the parking gear portion (the groove portion of the mold provided to form the parking gear) cannot be filled with the material, which may be a defective product.
Disclosure of Invention
The present invention has been made in view of the above problems, and an object of the present invention is to provide a forging die for a pulley shaft, which can fill the entire die, particularly a parking gear portion, with a material even if a high Si steel is used for a sub-hot forging process.
(1) In order to achieve the above object, the present invention provides a forging die for manufacturing a pulley shaft of a belt-type continuously variable transmission in which a shaft portion, a conical pulley portion extending outward in a radial direction of the shaft portion, and an annular parking gear protruding from a bottom surface of a cone of the pulley portion in an axial direction of the shaft portion in the vicinity of an outer peripheral portion of the pulley portion, are integrally forged, wherein a die cavity formed by an upper die and a lower die includes a shaping portion for shaping the pulley shaft, a relief space extending outward in the radial direction of the pulley portion from a peripheral portion of the shaping portion corresponding to an outer peripheral edge of the pulley portion and allowing burrs to flow out, the relief space includes a first space formed outward in the radial direction of a top portion of the parking gear and a second space formed outward in the radial direction of a bottom portion of the parking gear, the flow resistance of the burr of the first space is set to be larger than the flow resistance of the burr of the second space.
(2) Preferably, the flow area of the burr of the first space is set smaller than the flow area of the burr of the second space.
(3) Preferably, a distance between a die surface of the upper die and a die surface of the lower die in the first space is set to be smaller than a distance between a die surface of the upper die and a die surface of the lower die in the second space.
(4) Further, it is preferable that a high silicon steel containing silicon (Si) in an amount of 0.8 to 1.0 mass% is used as a material, and a heating temperature for the material is a sub-hot forging between a hot forging and a warm forging.
According to the present invention, since the relief space, through which the burr flows out, is provided so as to extend radially outward of the pulley portion from the peripheral edge portion of the shaped portion corresponding to the outer peripheral edge of the pulley portion, and the flow resistance of the first space formed radially outward of the tooth top portion of the parking gear is made larger than the flow resistance of the second space formed radially outward of the tooth bottom portion of the parking gear, the outflow of the material to the relief space in the vicinity of the groove portion of the mold forming the tooth top portion of the parking gear can be further suppressed, the inflow of the material into the groove portion can be ensured, defects in the tooth top portion of the parking gear, which is an important element of the product, can be prevented, and the occurrence of defective products can be reduced.
Further, according to the present invention, since the flow area of the burr of the first space is set smaller than the flow area of the burr of the second space to form the difference in flow resistance, the shape of the mold can be simplified, and further, since the distance between the die surface of the upper die and the die surface of the lower die set in the first space is set smaller than the distance between the die surface of the upper die and the die surface of the lower die in the second space to form the difference in flow resistance, the shape of the mold can be simplified.
Further, since the high Si steel is produced by the sub-hot forging using the high Si steel as a material, the durability of the product can be improved after the parking gear portion (particularly, the tooth top portion) is filled with the material, and the micro shot blasting process in the subsequent step can be omitted.
Drawings
FIG. 1 is an explanatory view showing a forging process for a workpiece, wherein (a) shows a first process, (b) shows a second process, (c) shows a third process, and (d) shows a fourth process;
FIG. 2 is a partially omitted cross-sectional view showing an outline of a forging die according to an embodiment of the present invention;
FIG. 3 is a plan view of a parking gear side of a pulley shaft formed by forging die set according to an embodiment of the present invention;
FIG. 4 is a sectional view taken along line A-A of FIG. 3;
fig. 5 is a sectional view taken along line B-B of fig. 3.
Description of the marks
10: belt wheel axle
11 d: shaft part
12 d: pulley part
13 d: parking gear
14 d: flash (flash)
100: model (model)
104: upper die
104 a: die surface
106: lower die
106 a: die surface
110: shaping part
120: release space
120 a: the first space
120 b: second space
Da: die face distance of the first space 120a
Db: die face distance of the second space 120b
Detailed Description
Embodiments of the present invention will be described below with reference to the drawings.
The embodiments described below are merely examples, and various modifications and technical applications that are not explicitly described in the embodiments below are not excluded.
A process of machining a workpiece to manufacture a pulley shaft will be described with reference to fig. 1.
First, as a pre-step of forging, a cylindrical workpiece (not shown) made of high Si steel is heated to 1120 to 1160 ℃ (sub-hot forging).
Thereafter, the heated columnar workpiece is subjected to forging in the first step to form a first workpiece 10a having a short axis 11a shown in fig. 1 (a).
Next, the first workpiece 10a is subjected to forging in the second step to form a second workpiece 10b having a major axis 11b shown in fig. 1 (b).
Next, the second workpiece 10b is subjected to forging in a third step to form a third workpiece 10c having a long axis 11c and a substantially spherical pulley preparation portion 12c shown in fig. 1 (c).
Further, the third workpiece 10c is placed on a forging die (hereinafter simply referred to as a die) 100 of the present embodiment shown in fig. 2, and forging processing in a fourth step is performed to form a fourth workpiece 10d including the shaft portion 11d, the pulley portion 12d, and the parking gear 13d shown in fig. 1 (d).
In the fourth member 10d, a flash 14d remains, which is formed by the outflow of the material (flash) into a release space (described later) of the mold 100. By cutting off the burr 14d in a post-process, the pulley shaft 10 that retains the shape of the final product is obtained.
Fig. 2 is a partially omitted cross-sectional view of a mold 100 for carrying out the fourth step.
As is well known in the art, a forging die is originally composed of a plurality of parts, and a driving device for driving the die, a push-out pin for ejecting a workpiece from the die, and the like are generally arranged, but in fig. 2, a well-known configuration is usually omitted in order to clarify the shape of the cavity 102 of the die 100.
The cavity 102 formed by the upper mold 104 and the lower mold 106 of the mold 100 includes a shaping portion 110 that forms a main body portion (portion excluding the flash) of the pulley shaft 10, and a relief space 120 that extends from a peripheral edge portion of the shaping portion 110 and allows the flash of the material to flow out.
Between the two dot-dash lines C, D (corresponding to the positions of the outer peripheral edges of the pulley portion 12 d) in fig. 2 is the shaped portion 110, and outside thereof is the relief space 120.
In the shaped portion 110, a shaft forming portion 111 forming the shaft portion 11d, a pulley forming portion 112 forming the pulley portion 12d, and a gear groove portion 113 forming the parking gear 13d are formed in accordance with the shape of the pulley shaft 10.
The relief space 120 extends from the outer peripheral edge of the pulley forming portion 112 (the position indicated by the dashed line C, D) to communicate with the inside of the pulley portion 112 (the shaped portion 110).
Fig. 3 is a plan view of the pulley shaft 10 viewed from the parking gear 13d side, and a part of the release space 120 is indicated by a two-dot chain line.
As is apparent from fig. 3, the parking gear 13d is formed of an annular body having a diameter slightly smaller than that of the pulley portion 12d, and has a plurality of tooth tips 132d with which the side surface 131d engages with a parking rod, not shown, and a plurality of tooth bottoms 133d between the tooth tips 132 d.
The relief space 120 includes a first space 120a formed in an extension of the tooth top portion 132d (radially outward of the tooth top portion 132 d), and a second space 120b formed in an extension of the tooth bottom portion 133d (radially outward of the tooth top portion 133 d).
As shown in fig. 4 and 5, the distance Da between the die surface 104a of the upper die 104 and the die surface 106a of the lower die 106 in the first space 120a is set smaller than the distance Db between the die surface 104a of the upper die 104 and the die surface 106a of the lower die 106 in the second space 120b, so that the flow resistance of the burr in the first space 120a is larger than the flow resistance of the burr in the second space 120 b. The two-dot chain line shown in fig. 5 indicates the cross-sectional profile of the tooth crest 132d shown in fig. 4.
Since the forging die is configured as described above, the flow resistance of the burr formed in the first space 120a radially outward of the tooth crest 132d is made larger than that of the other portion (the second space 120b), and therefore, even when the pulley shaft is manufactured under a condition where the fluidity of the material is lowered during the sub-hot forging using the high Si steel as the material, the gear groove portion 113 for forming the tooth crest 132d can be filled with the material, and the occurrence of defective products can be suppressed.
Further, since the flow resistance of the burr of the second space 120b is reduced, an increase in the molding load of the mold 100 can be suppressed, and the life of the mold 100 can be ensured.
While the embodiments of the present invention have been described above, the present invention can be implemented by appropriately modifying the embodiments.
For example, in the above embodiment, the distance between the die surfaces 104a and 106a of the mold 100 of the first and second spaces 120a and 120b is changed to provide a configuration in which a difference is provided in the flow resistance of the burr, and the distance between the die surfaces 104a and 106a is made equal, and a projection or the like is projected from the die surfaces 104a and 106a of the first space 120a, whereby the flow area of the burr is reduced (the flow resistance is increased), whereby the same effect as in the above embodiment can be obtained.
In the present embodiment, high Si steel having a silicon (Si) content of 0.8 to 4.0 mass% is used as the material to be forged, but the material to be forged is not limited thereto, and various metal materials can be applied.
In addition, the present forging die is suitable for the sub-hot forging in which the heating temperature of the material is intermediate between the hot forging and the warm forging as exemplified in the embodiment, but is not limited to the sub-hot forging, and may be applied to other forging techniques.
Claims (4)
1. A forging die for manufacturing a pulley shaft of a belt-type continuously variable transmission, in which a shaft portion, a conical pulley portion extending outward in a radial direction of the shaft portion, and an annular parking gear protruding from a bottom surface of a cone of the pulley portion in an axial direction of the shaft portion in the vicinity of an outer peripheral portion of the pulley portion are integrally forged and molded,
the die cavity formed by the upper die and the lower die is provided with a shaping part for shaping the pulley shaft, and a release space which is arranged from the peripheral part of the shaping part corresponding to the outer peripheral edge of the pulley part to extend towards the radial outside of the pulley part and enables the flash to flow out,
the relief space has a first space formed radially outward of a tooth top portion of the parking gear, and a second space formed radially outward of a tooth bottom portion of the parking gear,
the flow resistance of the burr of the first space is set to be larger than the flow resistance of the burr of the second space.
2. The forging die set according to claim 1,
the flow area of the burr of the first space is set smaller than the flow area of the burr of the second space.
3. The forging die set according to claim 2,
the distance between the die surface of the upper die and the die surface of the lower die in the first space is set to be smaller than the distance between the die surface of the upper die and the die surface of the lower die in the second space.
4. The forging die set as recited in claim 1 to 3,
a high-silicon steel containing silicon (Si) in an amount of 0.8 to 1.0 mass% is used as a material, and the heating temperature for the material is sub-hot forging between hot forging and warm forging.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2017-207203 | 2017-10-26 | ||
| JP2017207203A JP6953275B2 (en) | 2017-10-26 | 2017-10-26 | Forging die |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN109702130A CN109702130A (en) | 2019-05-03 |
| CN109702130B true CN109702130B (en) | 2021-06-15 |
Family
ID=66254739
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201811255986.1A Active CN109702130B (en) | 2017-10-26 | 2018-10-26 | Forging mold |
Country Status (2)
| Country | Link |
|---|---|
| JP (1) | JP6953275B2 (en) |
| CN (1) | CN109702130B (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP7008876B2 (en) * | 2019-09-20 | 2022-01-25 | 本田技研工業株式会社 | Forging method |
| CN111618541A (en) * | 2020-05-20 | 2020-09-04 | 江苏威鹰机械有限公司 | Precision forging plastic forming process of belt wheel shaft for stepless speed changer |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4294101A (en) * | 1979-01-12 | 1981-10-13 | Diemer Donald J | Method of making single or double flanged track tractor roller for off-highway equipment |
| JP2000117387A (en) * | 1998-10-16 | 2000-04-25 | Honda Motor Co Ltd | Combined forming method |
| JP2012183563A (en) * | 2011-03-07 | 2012-09-27 | Jtekt Corp | Method of manufacturing shaft member for wheel rolling bearing device |
| JP2012207247A (en) * | 2011-03-29 | 2012-10-25 | Aichi Steel Works Ltd | Carburizing member, steel for carburizing member and method for producing carburizing member |
| CN103097561A (en) * | 2010-04-19 | 2013-05-08 | 新日铁住金株式会社 | Steel component having excellent temper softening resistance |
| CN103949575A (en) * | 2014-05-19 | 2014-07-30 | 莱芜鑫科汽车零部件有限公司 | Gearbox main shaft vertical forging production method and special forging mold |
| CN104028726A (en) * | 2014-04-25 | 2014-09-10 | 浙江工业大学 | Multi-directional extrusion casting mold for aluminum alloy transmission shell and casting method |
Family Cites Families (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP3211157B2 (en) * | 1997-12-22 | 2001-09-25 | 株式会社フジユニバンス | Slide pulley for belt type continuously variable transmission and method of manufacturing the same |
| JP4946166B2 (en) * | 2006-05-11 | 2012-06-06 | 愛知製鋼株式会社 | Manufacturing method of molded product with tooth profile |
| CN201211548Y (en) * | 2008-06-25 | 2009-03-25 | 南京汽车锻造有限公司 | Forging mould of motor vehicle rear-wheel spindle |
| CN101804770B (en) * | 2009-02-17 | 2015-03-04 | 株式会社捷太格特 | Wheel bearing device and manufacturing method therefor |
| CN201609749U (en) * | 2010-03-19 | 2010-10-20 | 重庆杰信模具有限公司 | Crankshaft forging mold |
| CN103707017B (en) * | 2012-10-01 | 2016-04-20 | 江苏威鹰机械有限公司 | CVT automatic gear-box V-type belt wheel axle finish forge plastic forming technique |
| CN203548540U (en) * | 2013-11-30 | 2014-04-16 | 承田汽车配件工业（浙江）有限公司 | Driving belt wheel shaft |
| CN203926351U (en) * | 2014-06-12 | 2014-11-05 | 江苏威鹰机械有限公司 | CVT automatic transmission V-type belt shaft fine forge piece |
| CN206483963U (en) * | 2016-12-09 | 2017-09-12 | 衡阳市大成锅炉有限公司 | A kind of forging mold for machining cam axle |
| CN106363124B (en) * | 2016-12-09 | 2018-12-14 | 湖南高致精工机械有限公司 | A kind of cam axis processing technique and forging mold |
-
2017
- 2017-10-26 JP JP2017207203A patent/JP6953275B2/en active Active
-
2018
- 2018-10-26 CN CN201811255986.1A patent/CN109702130B/en active Active
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4294101A (en) * | 1979-01-12 | 1981-10-13 | Diemer Donald J | Method of making single or double flanged track tractor roller for off-highway equipment |
| JP2000117387A (en) * | 1998-10-16 | 2000-04-25 | Honda Motor Co Ltd | Combined forming method |
| CN103097561A (en) * | 2010-04-19 | 2013-05-08 | 新日铁住金株式会社 | Steel component having excellent temper softening resistance |
| JP2012183563A (en) * | 2011-03-07 | 2012-09-27 | Jtekt Corp | Method of manufacturing shaft member for wheel rolling bearing device |
| JP2012207247A (en) * | 2011-03-29 | 2012-10-25 | Aichi Steel Works Ltd | Carburizing member, steel for carburizing member and method for producing carburizing member |
| CN104028726A (en) * | 2014-04-25 | 2014-09-10 | 浙江工业大学 | Multi-directional extrusion casting mold for aluminum alloy transmission shell and casting method |
| CN103949575A (en) * | 2014-05-19 | 2014-07-30 | 莱芜鑫科汽车零部件有限公司 | Gearbox main shaft vertical forging production method and special forging mold |
Also Published As
| Publication number | Publication date |
|---|---|
| JP2019076943A (en) | 2019-05-23 |
| JP6953275B2 (en) | 2021-10-27 |
| CN109702130A (en) | 2019-05-03 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN109702130B (en) | Forging mold | |
| US9289814B2 (en) | Spur toothing on a coupling element for transmitting torques | |
| CN109702137B (en) | Method for manufacturing pulley shaft for belt type stepless transmission | |
| EP1975423B1 (en) | Hollow power transmission shaft | |
| KR102253535B1 (en) | Method for Producing Stamped Parts | |
| JP4907846B2 (en) | Gear, gear manufacturing method and apparatus | |
| US20180080538A1 (en) | Method for producing a stator for a camshaft adjuster | |
| WO2017163189A1 (en) | A method of manufacturing a crown wheel, and a crown wheel | |
| JP2010537047A (en) | Powder metal gear with variable case depth and manufacturing method thereof | |
| JP3503816B2 (en) | Bevel gear with web cold forging die and method of manufacturing bevel gear with web | |
| JP4853776B2 (en) | CVT shaft and manufacturing method thereof | |
| US7308813B2 (en) | Clutch housing and method for manufacturing the same | |
| JP3904068B2 (en) | Spacer for drive pinion and manufacturing method thereof | |
| JP4383151B2 (en) | Manufacturing method of helical gear | |
| JP4653141B2 (en) | Tooth formation method | |
| JP4145924B2 (en) | Tooth profile forming method | |
| KR100385537B1 (en) | A method for manufacturing the double sychronizer ring of transmission gear box of a vechile | |
| JP2008275077A (en) | Shaft for continuously variable transmission, and its manufacturing method | |
| JP3674756B2 (en) | Cold forging method for disc parts with shafts | |
| KR100612758B1 (en) | Method for Fabrication of Spur Gear with High Precise Dimension | |
| JP2005103601A (en) | Method for manufacturing tooth form component | |
| JP4638302B2 (en) | Cold forged bevel gear | |
| KR100429946B1 (en) | Method for Manufacturing Double Spur Gear in One Body by Cold Forging | |
| JPH0584538A (en) | Manufacture of synchronizer ring | |
| JPH11197784A (en) | Manufacture of input/output disk of troidal continuously variable transmission |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |