KR200458880Y1 - Forging shape for the lower part spline of one way clutch inner race in 6-speed automatic transmission - Google Patents

Abstract

The present invention relates to a method of forging a lower splined body for a one-way clutch inner race of a six-speed automatic transmission for a vehicle. In the present invention, a tooth having an outer diameter of a first radius and a lower end of the tooth are connected to and formed with a lower end than the first radius. And a body portion having a small second radius upper outer diameter portion and a third radius lower outer diameter portion smaller than the second radius, wherein the upper outer diameter portion and the lower outer diameter portion are formed to have a gradient angle of the six-speed automatic transmission. A finisher step lower spline body forging for one-way clutch innerlace is provided.

Inner race; Lower spline body, finisher geometry, precision hot forging

Description

FORGING SHAPE FOR THE LOWER PART SPLINE OF ONE WAY CLUTCH INNER RACE IN 6-SPEED AUTOMATIC TRANSMISSION} for one-way clutch inner race of six-speed automatic transmission

The present invention relates to a lower spline body forging for a six-speed automatic transmission for a one-way clutch inner race, and more particularly, to improve the dimensional accuracy of the final forging in forging a large diameter lower spline body constituting the inner race. The present invention relates to a lower spline body forging for a one-way clutch inner race for a six-speed automatic transmission for automobiles to minimize machining margins.

A planetary gear and a one-way clutch (one-way clutch) are combined in the planet carrier, which is a key device for changing the gear ratio without stopping power when driving a car. The inner race 1 is an important component for transmitting power in the one-way clutch, and the disc and the inner race are assembled in the hub gear type to induce slip and adjust the gap during power transmission.

1 is a view of the final product of the inner race of the automatic transmission one-way clutch. As shown in Fig. 1, the inner race 1 has a very complicated cross-sectional shape, and spline teeth are formed on the outer diameter portion and splines are formed on the inner diameter portion at intervals of 120 °. Manufacturing these parts in one piece requires a lot of processes and increases production costs. In order to solve this problem, as shown in FIG. 1 (b), the lower spline body 11 and the small diameter upper spline body 12 are manufactured separately, and then the two parts are electron beam welded 13. They are combined to each other to produce an integral form of an inner race assembly.

Figure 2 compares the shape of the conventional lower spline body forging and the machining shape. As shown in Fig. 2, since the hot forging 2 having a cylindrical shape is conventionally used for manufacturing the lower spline body forging, a large amount of material is removed when forming a machining shape, and a long time is required for machining. It was a disadvantageous and expensive one.

The present invention is to solve the above problems, by designing the finisher shape by predicting the deformation occurring during the piercing process in hot forging the lower spline for the inner race, to improve the dimensional accuracy of the forged product, as well as the lower spline It is an object of the present invention to provide a hot forging method that can significantly reduce the amount of machining by applying an internal / external diameter machining allowance of a large forging such as 1 mm or less, and a finisher and a piercing process.

The above object of the present invention relates to a finisher step lower spline body forging for one-way clutch inner race of a six-speed automatic transmission, and having a tooth portion having an outer diameter of a first radius, and connected to a lower end of the tooth portion, A six-speed automatic transmission one-way characterized in that it is provided with a body portion having a small second radius upper outer diameter portion and a third radius lower outer diameter portion smaller than the second radius, wherein the upper outer diameter portion and the lower outer diameter portion is formed to have a gradient angle. Achieveable by finisher stage lower spline body forging for clutch innerlace.

The draft angle is 2 to 3 °, and the diameter of the first radius is 0.8 to 1.2 mm larger and the diameter of the second radius is 0.8 to 1.4 when compared to the lower spline body forging for the final six-speed automatic transmission one-way clutch inner race. The larger the diameter, the smaller the diameter of the third radius is preferably 0.5 ~ 0.8mm.

The lower spline hot forging uses the principle that the diameter of the lower part of the product which comes into direct contact with the piercing die in the piercing process after forming the finisher is increased, and the diameter of the upper part of the body and the tooth is reduced, so that the product dimensions after deformation can be precisely obtained. Technology.

Through this technology, precision hot forging with high dimensional accuracy can be obtained with the machining allowance of the final forging to be 1 mm or less. As a result, the input amount of the material can be significantly reduced compared to the forged product, which was 1.5 mm or more, and the cost reduction of the forged product can be achieved, and the machining time and cost are reduced due to the small amount of machining.

Preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

3 is a lower spline forged product of an improved shape in order to reduce the amount of machining, FIG. 4 is a product shape diagram forged into an improved shape, and FIG. 5 is a hot forging process diagram of the lower spline forged product. The hot forging process includes a raw material cutting step 51 for cutting raw materials, an upset molding step 52 for upset molding the cut raw materials, a blocker forming step 53, a finisher molding step 54, and piercing / trimming. Step 55 is made.

As shown in FIG. 3, when the teeth 31 and the body 32 of the lower spline forging 3 of the comparative example are forged into outer diameters having different dimensions, the material to be cut is significantly reduced and the machining time and cost are reduced. Can be reduced. However, in the case of forging the lower spline forging (3) in the shape of Figure 3, product deformation occurs in the piercing process after hot finish forging the finisher. As shown in FIG. 4, when hot forging is performed using the lower spline forged product 3 shown in FIG. 3, deformation occurs in the trimming process, so that the shape of the lower part of the product body in the shape of the lower spline forged product 4 is upward. It can be seen that it is wider than. This shape can be more clearly seen in the cross-sectional photograph 41 of the completed lower spline forged product after performing hot forging using the lower spline forged product 3 shown in FIG. 3. When the cross-sectional photograph 41 of the design spline contour 42 of the lower spline forging was confirmed by overlapping with the design drawing of FIG. 4, the lower part of the body of the cross-sectional photograph 41 of the lower spline forging was enlarged by 0.4 mm (0.8 mm in diameter) on one side. It can be seen that the upper part of the body and the lower part of the spline are reduced in dimensions by 0.5 mm (1.0 mm in diameter) on one side.

When the thickness is thin, such as the lower spline hot forging, deformation occurs in the piercing process, so that machining does not occur even when deformation is performed, and machining allowances for inner and outer diameters (34), (35) ) Is forging with a minimum of 1.5mm.

The present invention is a method of manufacturing a lower spline hot forging to significantly reduce the machining margin of the lower hot forging and also improve the dimensional accuracy. It satisfies the processing margin of 1mm or less and prevents the lower part of the lower spline body from spreading. In this way, a precise hot forging of the lower spline of the inner race for a six-speed automatic transmission for automobiles can be obtained.

FIG. 6 is a shape of a lower spline final forged product to be obtained by a development technique, FIG. 7 is a finisher forged shape for obtaining a final forged product, and FIG. 8 shows a dimension difference between the final forged product and the finisher shape. FIG. 9 is a mold shape for piercing a molded finisher shape, FIG. 10 is an enlarged shape view of a piercing mold, and FIG. 11 is a trimming mold view.

In FIG. 6, the tooth outer diameter 35 and the trunk outer diameter 36 of the lower spline final forged product 3 are the dimensions when a machining allowance of 1 mm is applied to the final machined product, as shown in FIG. 7 to obtain such a shape. Similarly, the finisher shape (6) increases the tooth outer diameter (61) dimension by 0.8 to 1.2 mm (one side 0.4 to 0.6 mm) and the lower (62) dimension of the outer diameter of the body compared to the final forging shape (3) by 0.5 to 0.8 mm. (Single 0.25 ~ 0.4mm) Apply small, and apply upper dimension (63) of the outer diameter of the trunk to 0.8 ~ 1.4mm (0.4 ~ 0.7mm on one side) to make the draft angle 64 2 ~ 3 °. The outline shown by the thick solid line 65 in FIG. 8 is the shape of the finisher forging, and the outline shown by the dashed line 37 is the shape of the final forged product deformed in the piercing process.

Finisher-formed forgings are placed on the piercing die 71 of FIG. 9 and then pressurized with a piercing punch 72 to remove the center portion. At this time, the dimension of the piercing die is applied to 0.25-0.4mm (0.5-0.8mm in diameter) larger than the lower dimension of the body part of the finisher forging so that the deformed dimension in the piercing process can be the target dimension of the final forging. The dimensions of the trimming die 73 in the trimming process of FIG. 11 apply the dimensions after deformation in the piercing process.

FIG. 12 is a simulation process for the lower spline precision forging process, and FIG. 13 shows the finisher forging predicted from the simulation and the shape after deformation by piercing. Figure 14 shows the shape of the lower spline final forging pierced after hot forging by the present invention, Figure 15 shows the cross-sectional shape of the forging.

According to the simulation of FIG. 12, it was found that the lower splined body lower end portion was enlarged by the piercing processes 82, 83, and 84 through the piercing process (81), and the dimension was increased, and the upper end portion of the body was reduced in diameter. Can be. In FIG. 13, the precise dimensions of the final forged product can be obtained by the shape change before the piercing 85 and after the piercing 86. In the shape of the final forged product 9 to which the subject innovation of FIG. 14 is applied, it is possible to confirm that the phenomenon in which the size of the lower end of the product appeared in the final forged product 4 of the existing technology does not appear at all.

Although specific embodiments of the present invention have been described and illustrated above, it will be apparent that various modifications may be made by those skilled in the art without departing from the technical spirit of the present invention. Such modified embodiments should not be understood individually from the spirit and scope of the present invention, but should fall within the claims appended to the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS The figure of the final processed product of the inner race of an automatic transmission one-way clutch.

Figure 2 is a shape of the existing forging for manufacturing the lower spline.

3 is a forged view of the lower spline shape of the comparative example for reducing the amount of machining.

4 is a view of the product forged using the lower spline of FIG.

5 is an inner race hot forging process.

Figure 6 is the shape of the inner race final forging by the development outline.

7 is a finisher forged shape by the development outline.

8 is a dimension difference between the final forged product and the finisher shape;

9 is a piercing mold shape view.

10 is an enlarged shape view of a piercing die.

11 is a trimming mold diagram.

12 is an inner race precision forging process by simulation.

13 is a shape after deformation by the finisher forging and piercing.

14 is a shape of the inner race final forging pierced after hot forging by the inventive technique.

15 is a cross-sectional shape of a forged product.

***** Brief description of the main symbols on the drawing *****

1: Inner race assembly workpiece

11: inner race large diameter lower spline body

12: inner race small diameter upper spline body

13: electron beam welding part

2: conventional lower spline hot forging shape

3: lower spline hot forging shape according to the present invention

31: Lower spline teeth 32: Lower spline body

33: Machining allowance for outer diameter 34: Machining allowance for outer diameter 34

35. Lower spline tooth outer diameter 36. Lower body outer diameter

37. Bottom Spline Hot Forging Contour

4. Lower spline hot forging

41. Lower spline hot forging cross section

42. Lower Spline Design Outline

51. Raw material cutting step 52. Upset molding step

53. Blocker forming step 54. Finisher forming step

55. Piercing / Trimming

6. Process diagram of lower spline finisher according to the present invention

61. Outer Diameter of Lower Spline Teeth According to the Present Invention

62. Outer diameter of lower spline body lower end according to the present invention

63. Outer Diameter of Lower Spline Body Upper End According to the Present Invention

64. Lower spline trunk draft angle according to the present invention

65. Lower spline finisher contours according to the present invention

71. Piercing die 72. Piercing punch

73. Trimming die 74. Trimming punch

81. Finisher Shape by Simulation

82. Piercing Process Shape by Simulation

83. Piercing Deformation Shape by Simulation

84. Piercing Completion Shape by Simulation

85. Shape before and after deformation of piercing process by simulation

9. Lower spline forging according to the present invention

91. Cross section of the lower spline forging according to the present invention

Claims (4)

The shape of the lower spline body forging of the finisher stage corresponding to the previous stage of the piercing stage during the forming step of the lower spline body forging for the one-way clutch inner race of the six-speed automatic transmission, A cylindrical body portion; And a tooth portion connected to the upper end and formed with a spline tooth along a top circumference of the body portion, Compared with the lower splined body forging of the piercing step, the outer diameter of the tooth is larger by 0.8-1.2 mm, the outer diameter of the upper part of the body is larger by 0.8-1.4 mm, and the outer diameter of the lower part of the body is 0.5- Formed as small as 0.8mm, The outer circumferential surface of the body portion is one direction of the six-speed automatic transmission, characterized in that it has a gradient that is inclined outwardly by an angle of 2 to 3 ° from the bottom to the top, based on the outer circumferential surface of the lower spline body forging of the piercing step Finisher step lower spline body forging for clutch inner race. delete delete The method according to claim 1, The dimension of the piercing die of the piercing step is 0.5 ~ 0.8mm larger than the outer diameter of the bottom of the torso of the lower spline body forging of the finisher step so that the deformed dimension in the piercing process becomes the target dimension of the final forging. Finisher stage lower spline body forging for one-way clutch inner race of high speed automatic transmission.

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