JP3642509B2 - Tooth profile sizing mold - Google Patents

Description

[0001]
[Industrial application fields]
The present invention relates to a tooth profile sizing die for finishing a tooth profile of a molded product roughly processed by forging or the like to a predetermined accuracy.
[0002]
[Prior art]
Conventionally, when manufacturing gears used in power transmission mechanisms of automobiles, intermediate materials are roughened by a series of forging processes such as upset molding in the hot or warm temperature range, extrusion molding of the preliminary tooth profile, and drilling. After processing, the gears are formed by performing sizing in the cold temperature region to perform ironing (ioning) on the preliminary tooth profile portion in order to finish the preliminary tooth profile portion formed by the extrusion molding to a predetermined tooth profile accuracy. It was.
[0003]
This sizing process will be described with reference to FIG. A tooth profile sizing die 151 shown in the figure includes an installed lower die 171 and an upper die 161 that is disposed so as to be able to advance and retract on the same axis with respect to the lower die 171. The lower die 171 is provided with a die 172 having a sizing tooth die 172a on the inner periphery, and a guide ring 174 and a knockout pin 176 on which the intermediate material W104 is placed with an interval on the inner periphery side of the die 172. An engraving space 180 is defined between the guide ring 174 and the sizing tooth mold 172a for inserting the preliminary tooth profile 115 of the intermediate material W104. When sizing is performed with the tooth profile sizing die 151, the intermediate member W104 is previously disposed on the knockout pin 176 of the lower die 171 as shown in the left half of FIG. Subsequently, the upper die 161 is lowered, and the intermediate material W104 is pressed downward by the lower end pressing surface 162 of the upper die 161. As shown in the right half of FIG. The preliminary tooth profile 115 was inserted into the carving space 180 and sizing was performed. Here, a chamfering 199 for guiding is formed at the end of the sizing tooth mold 172a on the side where the intermediate material W104 is inserted, and the preliminary tooth profile 115 of the intermediate material W104 is guided by the chamfering 199 to form a die engraving space. 180 was inserted.
[0004]
[Problems to be solved by the invention]
By using the tooth profile sizing die 151 as described above and sizing the preliminary tooth profile 115 of the intermediate material W104, a highly accurate tooth profile 116 can be obtained. Further, by the chamfering 199 of the sizing tooth mold 172a, the preliminary tooth profile 115 of the intermediate material W104 can be matched with the mold engraving space 180, and the preliminary tooth profile 115 can be easily inserted into the mold engraving space 180. However, in the chamfer 199 of the sizing tooth mold 172a, when the sizing tooth mold 172a and the preliminary tooth profile 115 of the intermediate material W104 overlap with the intermediate material W104 placed, the preliminary tooth profile of the intermediate material W104 at the initial stage of sizing. The part 115 presses the sizing tooth mold 172a of the die 172, and the sizing tooth mold 172a is deformed, and the die life of the die 172 may be reduced. Further, when the preliminary tooth profile 115 presses the sizing tooth mold 172a, the tooth profile accuracy of the tooth profile 116 in the formed gear W105 is lowered, and a defective product may be generated in some cases.
[0005]
SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a tooth profile sizing die that solves the above-described problems, suppresses a decrease in die life of the die, and maintains the tooth profile accuracy of the tooth profile portion continuously and satisfactorily.
[0006]
[Means for Solving the Problems]
The structure of the mold for tooth profile sizing of the present invention is as follows.
[0007]
In a tooth profile sizing mold comprising a die having a sizing tooth profile corresponding to a tooth profile portion of a desired gear on the inner periphery, and an alignment device placed on one end of the die, the alignment device includes: A positioning piece that has the same shape as the sizing tooth shape and has a mountain-shaped tooth tip that inclines toward both ends from the center in the width direction is provided at a position that matches the sizing tooth shape. An elastic member having elasticity to be biased to the side is disposed.
[0008]
【Example】
Embodiments of the present invention will be described below with reference to FIGS.
[0009]
(E) of FIG. 1 represents a gear W5 according to an embodiment of the present invention, and a process of manufacturing the gear W5 is illustrated in FIG. The process of manufacturing the gear W5 will be described with reference to the drawings. First, a columnar material W0 as shown in FIG. 1A is pressed in the axial direction to form a disc shape as shown in FIG. The disc material W1 is formed. Subsequently, the central part of both ends in the axial direction of the disk material W1 is pressed to have recesses 11 and 12 at both ends as shown in FIG. 1 is formed, and the center of the partition wall 13 of the preliminary material W2 is continuously punched out. As shown in FIG. 1D, the substantially cylindrical pierced material W3 having the pierced hole 14 on the inner periphery is formed. Form.
[0010]
Next, this pierced material W3 is forward-extruded and, as shown in FIG. 1 (e), the preliminary tooth portion 15 and the large-diameter flange portion 17 on the outer periphery, and the large-diameter and small-diameter pierce holes 14a and 14b on the inner periphery. It forms in intermediate material W4 provided with. This tooth forming process will be described with reference to FIG.
[0011]
FIG. 2 shows the forging die 21, the left half part before molding and the right half part after molding. Reference numeral 41 denotes a lower die, which includes a die 43 having a forming tooth profile 43 a on the inner peripheral lower side, and a substrate 45 integrally below the die 43. On the inner peripheral side of the die 43 and the substrate 45, a cylindrical mandrel 46 having a large-diameter portion 46b that fits the substrate 45 on the lower side and a small-diameter portion 46a that fits the piercing hole 14 of the piercing material W3 on the upper side is arranged. Established. A step 46c for seating the piercing material W3 is formed between the large-diameter portion 46b and the small-diameter portion 46a of the mandrel 46, and a mold engraving space 47 is defined between the mandrel 46 and the die 43. The Reference numeral 31 denotes an upper die, which is disposed so as to be able to advance and retreat, facing the carving space 47 of the lower die 41.
[0012]
When the intermediate material W4 is formed from the piercing material W3 by the forging die 21, first, as shown in the left half of FIG. 2, the piercing material W3 in which the piercing hole 14 is inserted into the small diameter portion 46a of the mandrel 46 is used as the lower die. 41 is placed in the mold engraving space 47 and seated on the step 46 c of the mandrel 46. Thereafter, the upper die 31 is lowered to enter the die-sculpting space 47 and the piercing material W3 is pressed from above, and as shown in the right half of FIG. And the preliminary tooth profile 15 is formed. Thereby, the forming of the intermediate material W4 is completed.
[0013]
Next, a sizing process is performed on the preliminary tooth profile 15 of the intermediate material W4 to form a gear W5 having a tooth profile 16 of a predetermined size on the outer periphery as shown in FIG. This process will be described with reference to FIGS.
[0014]
FIG. 3 shows a mold 51 for tooth profile sizing. Reference numeral 71 denotes a lower die, which includes a die 72 having a sizing tooth die 72a for finishing on the inner periphery, a base 73 below the die 72, and is integrally fixed by a die cover 75 disposed on the outer periphery thereof. In addition, a cylindrical guide ring 74 on which the intermediate material W4 is placed is disposed on the inner peripheral side of the die 72 and the base 73 with a gap formed on the upper side, and the guide ring 74 and the sizing tooth mold 72a of the die 72 are arranged. A gap between the two forms a sculpture space 80. On the inner peripheral side of the guide ring 74, an upper knock pin 77 and a lower knock pin 79 that are integrally coupled by a bolt 81 are disposed. A lower flange 79a is provided at the lower end of the outer periphery of the lower knock pin 79, and an upper flange 74a is provided near the center of the inner periphery of the guide ring 74. A spring-like spring elastic body 83 is interposed between the upper and lower flanges 74a and 79a.
[0015]
Two alignment devices 91 are placed on the upper ends of the die 72 and the die cover 75 at the same interval in the circumferential direction. This alignment device 91 has a horizontally long space 96 inside, a case 92 that opens to the inner peripheral side, a positioning piece 93 that protrudes from the opening of the case 92 and can be stored in the horizontally long space 96 of the case 92, and a positioning piece. 93, a fixed pin 95 that is fixed integrally with the positioning piece 93 and restricts movement of the positioning piece 93 to the inner peripheral side, and is accommodated in a horizontally long space 96 of the case 92, and has elasticity that urges the positioning piece 93 toward the inner peripheral side. Member 94. Here, the positioning piece 93 has a tooth tip 93a having substantially the same shape as that of one tooth of the sizing tooth mold 72a in plan view, and the positioning piece 93 is provided at a position where the tooth tip 93a matches the sizing tooth mold 72a. Further, the tooth tip 93a of the positioning piece 93 has a mountain shape inclined from the center in the width direction toward both ends, as shown in FIG.
[0016]
As shown in FIG. 3, 61 is an upper die, which is located on the same axis as the lower die 71, and has a pressing surface 62 having the same shape as the end surface on the flange 17 side of the intermediate material W4 at the lower end. The upper mold 61 is disposed so as to be able to advance and retract relative to the lower mold 71.
[0017]
When the gear W5 is formed from the intermediate material W4 with the tooth profile sizing die 51, the intermediate material W4 is inserted into the guide ring 74 from the preliminary tooth profile 15 side, and the intermediate material W4 is disposed on the guide ring 74. At this time, the preliminary tooth profile 15 of the intermediate member W4 and the positioning piece 93 of the alignment device 91 are in slight contact with each other.
[0018]
Subsequently, the upper die 61 is lowered and brought into contact with the intermediate material W4, and at the same time, the intermediate material W4 is pushed downward by the upper die 61. At this time, if the tooth tip 93a of the positioning piece 93 and the inter-tooth space S of the preliminary tooth profile portion 15 are close to matching, the intermediate material W4 has the preliminary tooth profile portion 15 along the inclination of the tooth tip 93a of the positioning piece 93. As shown in the left half of FIG. 4 and FIG. 6, the tooth tip 93 a of the positioning piece 93 and the interdental space S of the preliminary tooth profile portion 15 completely match each other. In addition, when the tooth top 93a of the positioning piece 93 and the preliminary tooth profile portion 15 are close to matching, the positioning piece 93 is pressed by the preliminary tooth profile portion 15, and once the positioning piece 93 is placed on the outer peripheral side, that is, inside the case 92. Extruded. However, since the positioning piece 93 is urged to the inner peripheral side by the elastic member 94 here, the intermediate tooth W4 is being inserted, and the preliminary tooth profile 15 is inclined by the pressing of the positioning piece 93 from the tooth tip 93a. The tooth tip 93a of the positioning piece 93 and the interdental space S of the preliminary tooth profile 15 are completely matched.
[0019]
In a state where the tooth tip 93a of the positioning piece 93 and the inter-tooth space S of the preliminary tooth profile 15 match, the intermediate material W4 is further pushed downward. Here, as shown in the right half of FIG. 4, the preliminary tooth profile 15 is guided by the tooth tip 93a of the positioning piece 93 and inserted into the die-cutting space 80 of the die 72, and is subjected to sizing by the sizing tooth pattern 72a. . During the sizing process, the positioning piece 93 is pressed by the flange portion 17 of the intermediate material W4 and stored in the horizontally long space 96 of the case 92. The sizing process is completed when the preliminary tooth profile 15 is completely inserted into the die-cutting space 80 of the die 72.
[0020]
As described above, in the above-described tooth shape sizing die 51, the alignment device 91 has the same shape as the sizing tooth die 72a of the die 72, and the positioning piece 93 having the mountain-shaped tooth tips 93a inclined from the center in the width direction toward both ends. Is provided at a position that matches the sizing tooth mold 72a, and an elastic member 94 having elasticity for urging the positioning piece 93 toward the inner peripheral side is disposed on the outer peripheral side of the positioning piece 93. The preliminary tooth profile 15 of the material W4 and the die engraving space 80 of the die 72 can be easily aligned.
[0021]
In the above embodiment, the two alignment devices 91 facing each other are arranged. However, the alignment devices 91 are not limited to two, and may be one or three or more.
[0022]
【The invention's effect】
As described above, according to the present invention, a tooth profile sizing die including a die having a sizing tooth shape corresponding to a tooth shape portion of a desired gear on the inner periphery, and an alignment device placed on one end of the die. In the mold, the positioning device is provided at a position where a positioning piece having a mountain-shaped tooth tip having the same shape as the die sizing tooth mold and inclined from the center in the width direction toward both ends coincides with the sizing tooth mold. Since an elastic member having elasticity for urging the positioning piece toward the inner peripheral side is arranged on the outer peripheral side of the intermediate member, the alignment device can easily align the preliminary tooth profile portion of the intermediate material and the die carving space. Therefore, during the sizing process as in the prior art, it is possible to prevent the preliminary tooth profile portion of the intermediate material from pressing the sizing tooth mold of the die and deforming the sizing tooth mold, thereby reducing the die life of the die. It can be. Moreover, it can suppress that the preliminary | backup tooth-form part of an intermediate material presses the sizing tooth type of a die | dye, and the tooth-type part of the shape | molded gear deform | transforms and a tooth type precision falls.
[Brief description of the drawings]
FIG. 1 is a cross-sectional front view showing a manufacturing process of a gear according to an embodiment of the present invention.
FIG. 2 is a partial cross-sectional front view showing a forging process of an intermediate material according to an embodiment of the present invention, in which the left half part is before forming and the right half part is after forming.
FIG. 3 is a partial sectional front view showing a first stage of a sizing process according to an embodiment of the present invention.
FIG. 4 is a partial cross-sectional front view showing a sizing process according to an embodiment of the present invention, wherein the left half represents a second stage and the right half represents a third stage.
FIG. 5 is a side view showing a positioning piece according to an embodiment of the present invention.
FIG. 6 is an explanatory diagram illustrating a second stage of a sizing process according to an embodiment of the present invention.
FIG. 7 is a partial cross-sectional front view showing a conventional sizing process, in which the left half is before molding and the right half is after molding.
[Explanation of symbols]
16 Tooth profile portion 72 Die 72a Sizing tooth mold 91 Positioning device 93 Positioning piece 93a Tooth tip 94 Elastic member W5 Gear

Claims (1)

A die (72) having a sizing tooth profile (72a) corresponding to the tooth profile (16) of the desired gear (W5) on the inner periphery, and an alignment device (1) placed on one end of the die (72) 91), and the positioning device (91) has the same shape as the sizing tooth mold (72a) of the die (72) and has a mountain shape inclined from the center in the width direction toward both ends. A positioning piece (93) having a tooth tip (93a) is provided at a position coincident with the sizing tooth mold (72a), and the positioning piece (93) is biased toward the outer peripheral side of the positioning piece (93). A tooth shape sizing mold, in which an elastic member (94) having elasticity is disposed.

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