JPH06304693A - Manufacture of gear - Google Patents

Abstract

PURPOSE:To shorten the time needed to manufacture of a gear and to uniformize the surface of a formed tooth profile part by continuously progressing the formation of a disk part and the formation of the tooth profile part, in the manufacturing method for gear integrally forming the disk part and the tooth profile part succeeded to the outer periphery of the disk part from a blank for working enabling plastic-working. CONSTITUTION:The blank 10 for working is interposed by compression in the condition of synchronously rotating in the same direction of a first die 3a being suitable to one side of the side surface shape of the disk part and a second die 3b being suitable to the other side of the side surface shape of the disk part to form the disk part. At the same time of this forming or after this forming, by using a tooth profile forming roller 4 and pressurizing the outer peripheral part of the disk part, the tooth profile part is formed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gear manufacturing method.

[0002]

2. Description of the Related Art As a method for manufacturing a large number of identical gears, a method of manufacturing a disk body having a predetermined shape by forging and forming a tooth profile portion on the outer peripheral portion of the disk body by rolling is adopted. However, even with this method, the manufacturing of the disk body and the molding of the tooth profile are separate steps, and therefore the productivity cannot be said to be sufficient.

For example, when a gear having the shape shown in FIG. 3 is manufactured by rolling, as shown in FIGS. 1 and 2, a prefabricated disk body (1) is rotated to form a tooth profile on its outer peripheral portion. The forming die (2) is pressed in a rolling state to form the tooth profile (1b) of the gear. Therefore, it is difficult to make the composition of the tooth profile formed by the peaks (20a) and the troughs (20b) of the molding die (20) of the mold (2) uniform.

The portion formed by the peak portion 20a corresponds to the valley portion of the tooth profile, and this portion is a portion formed by being pushed from the peripheral edge of the disk body by the peak portion 20a. A portion formed by the valley portion (20b) corresponds to a tooth-shaped crest portion, and corresponds to a gathering portion of the materials removed by pushing the crest portions (20a) (20a). in this way,
Since the molding conditions are different for the portions corresponding to the peaks and valleys of the tooth profile, there remains the problem that the strength of the tooth profile surface becomes uneven.

The present invention has been made in view of the above point, and describes "from a workable material (10) capable of being plastically processed, a disk portion (1a) and a tooth profile portion (1b) formed around the disk portion (1a). In the manufacturing method of the gear, which is integrally formed with the above, it is possible to shorten the time required for manufacturing the gear by allowing the molding of the disk portion and the molding of the tooth profile portion to proceed continuously, and the molded tooth profile portion The task is to homogenize the surface of (1b).

[0006]

[Technical Means] A technical means of the present invention for solving the above-mentioned problem is to provide a "pressing surface (31) of a first mold (3a) that matches the outer surface shape of a disk part (1a), and a disk part". The pressing surface (33) of the second mold (3b) matched with the inner surface shape of (1a) is opposed, and the tooth forming roller (4) is provided on the outer periphery of the boundary between the pressing surfaces (31) and (33). The first and second molds (3a) (3b), which are movably arranged and are rotated synchronously in the same direction with the work material (10) interposed between the pressing surfaces (31) (33). The disk part (1a) is formed by pressing the disk in the axial direction, and the mold part (41) on the outer periphery of the tooth forming roller (4) is pressed between the pressing surfaces (31) and (33) while the mold is rotated. The tooth-shaped portion (1b) is molded by applying pressure to the peripheral portion which is spread from the surface. ”

[0007]

The above technical means operates as follows. The work material (10) is the pressing surface (31) (33) of the first and second molds (3a) (3b).
These molds are interposed between the molds and are pressed in the rotating state to forge the disk portion (1a). Then, at the time of this forging, the peripheral edge of the material to be processed (10) is the pressing surface (31).
It extends and protrudes from the peripheral edge of the boundary between the (33) to the outer peripheral area, and this extended projection is pressed by the molding die (41) of the tooth forming roller (4). Then, the first and second molds (3
a) (3b) the pressure surface (31) (33) when the distance between them becomes a predetermined distance, that is, when the disk portion (1a) is molded into the final shape, the pressure surface (31) (33) The amount of spread protrusion from (1) becomes a predetermined value, and the tooth profile portion (1b) is molded into the final shape by the molding action of the molding die portion (41) of the tooth forming die roller (4).

[0008] Tooth profile (1b) formed by the tooth forming roller (4)
At the time of molding, the final shape is finished by pressing the spreading material into the molding die part (41) of the tooth forming die roller (4) in the rotating state, so the valley of the tooth profile part (1b) is It is possible to homogenize the surface of the part and the surface of the peak. In this way, the gear disk portion (1a) and the tooth profile portion (1b) can be simultaneously molded by one device.

[0009]

[Effect] When the material to be processed (10) is plastically machined into a gear, the disk part (1a) and the tooth profile part (1b) are finish-molded at the same time, so productivity is markedly higher than that of conventional products. And can be manufactured at low cost. Further, since the forging molding of the disk portion (1a) and the molding processing of the tooth profile portion can be performed at the same time, the manufacturing site may be narrow.

Further, when the tooth profile part (1b) is molded, the final shape is finished in such a manner that the spreading material is press-fitted into the molding part of the tooth forming mold roller (4) in the rotating state.
It is possible to homogenize the surface of the valley and the surface of the crest of the tooth profile (1b).

[0011]

Embodiments of the present invention described above will now be described in detail with reference to the drawings. In this embodiment, as shown in FIG. 4, a boss portion (12) is provided at the center of the disc portion (1a), a rim portion (11) is provided at the peripheral portion, and a tooth profile is provided on the outer periphery of the rim portion (11). Department (1
A so-called external gear having b) is manufactured. Therefore, as shown in FIG. 5, the first mold (3a) and the second mold (3b) are vertically opposed to each other. The first die (3a) is configured to be rotationally driven at a fixed position, the second die (3b) is opposed to the upper side of the first die (3a), and the second die (3b) can be moved laterally between them while maintaining an upright posture. Use a device equipped with tooth-forming rollers (4).

The second mold (3b) is supported by a support (5) so as to rotate about a rotation angle of the first mold (3a) by a certain angle θ. This support
(5) is moved up and down in the opposite direction coaxially with the axis of the first die (3a). In addition, this support (5) has a second
A drive device (51) for rotationally driving the die (3b) is attached.

Between the first mold (3a) and the second mold (3b),
Although the material to be processed (10) is interposed, the material to be processed (10) is a columnar or thick disk-shaped material, and the entire volume is as shown in FIG.
It matches the volume of the gear shown in. Also, of course,
The height or thickness of the cylindrical body or disc-shaped body is set to be larger than the tooth width of the tooth profile portion (1b) of the gear. The upper surface of the first mold (3a) is the pressing surface (31), and the disk part (1
It is shaped like the surface shape of the outer surface of a). Therefore,
The pressing surface (31) has a rim portion (11) and a tooth profile portion of the gear.
It comprises a peripheral stepped portion (31a) coinciding with (1b), a central concave portion (31b) coinciding with the boss (12), and a flat surface portion (31c) between them.

On the other hand, the pressing surface (33) of the second mold (3b) is also formed to have a surface shape suitable for the disk portion (1a) and the toothed portion (1b) on the inner surface of the gear, but in this embodiment, , Disk part (1
The pressure surface (33) facing the inner surface of a) is an umbrella-shaped end surface, and the inclination angle of the generatrix of this umbrella-shaped end surface (angle with respect to the plane perpendicular to the axis) matches the inclination angle θ of the axis. Therefore, in this embodiment, the generatrix below the pressure surface (33) (the left side line in the figure) is always perpendicular to the rotation axis of the first mold (3a) (with respect to the rotation surface of the pressure surface (31)). Parallel).

The pressurizing surface (33) has a rim portion of the above-mentioned gear which is formed by a combination of tapers.
(11) and the peripheral step (33a) matching the tooth profile (1b), and the boss
A central recess (33b) matching the (12) and an umbrella between them
(33c) is formed. First mold (3a) and second mold
A tooth profile supported rotatably on the outside of the inclination direction of the second mold (3b) (direction in which the generatrix of the second mold (3b) is horizontal) on the side of the boundary with (3b). A forming roller (4) is provided, and the tooth forming roller (4) is moved inward in the radial direction while maintaining the upright posture.

In this embodiment, since the thickness of the rim portion (11) and the tooth width of the tooth profile portion (1b) are matched, the forming die portion (41) of the tooth forming roller (4) is The thickness is the distance between the peripheral stepped portion (31a) of the pressing surface (31) (33) of the first and second molds (3a) (3b) in the closest state and the facing surface of the peripheral stepped portion (33a). Match. Further, roller parts (42) and (42) which are in contact with the outer peripheral body parts of the first and second molds (3a) and (3b) are formed above and below the molding die part (41).

The actual method of manufacturing a wheel in the final shape from the material 10 to be processed using the above apparatus will be described with reference to FIGS. In the method of this embodiment, the material to be processed (10) formed into a cylindrical body is used. This material
(10) is set in the first mold (3a) first, then the second mold
Material to be processed by lowering (3b) in the axial direction of the first die (3a)
(10) is the central recess (31b) of the pressing surface (31) of the first mold (3a)
And the central depression (33b) of the pressing surface (33) of the second mold (3b). At the same time, the roller parts (42) (42) of the tooth forming roller (4) are brought into contact with the outer peripheral body parts of the first and second molds (3a) (3b) from the outside, and the pressing surfaces (31) (33) Mold part (4
Insert 1).

In this state, as shown in FIG. 6, the first mold
(3a) and the second mold (3b) are synchronously rotated in the same direction to press the second mold (3b) downward. At the same time, the roller portions (42) (42) of the tooth forming roller (4) are pressed radially inward of the first and second molds (3a) and (3b) and the first and second molds (3a). Rolling contact is made with the outer circumference of the body of (3b). If this state is continued, the range of the work material (10) to the flat surface part (31c) of the pressing surface (31) of the first die (3a) by the so-called Surikogi forging action,
The material to be processed that has been filled in the range up to the umbrella-shaped portion (33c) of the pressing surface (33) of the second mold (3b) and then expanded is the peripheral step portion (31a) and the peripheral step portion. It projects between (33a).

Finally, as shown in FIG. 7, the workpiece material portion thus extended and projected has the forming die portion (41), the peripheral step portion (31a) and the peripheral step portion of the tooth forming roller (4). It is filled in the space surrounded by (33a). Then, in this filled state, the peripheral edge step portions (31a) (33a) and the upper and lower surfaces of the molding die portion (41) are in contact with each other. In this state, the portion corresponding to the disc portion (1a) is molded into the final shape, while the peripheral step portions (31a) (33a)
The work material part that has been extended and projected between the rims is finally the rim part (11).
And the tooth profile (1b).

Incidentally, until the final shape is finished in this way, the roller portion (42) (4) of the tooth forming roller (4) is
Since 2) is in contact with the outer peripheral body of the first and second molds (3a), (3b), burrs are less likely to occur. After this, the boss (1
When the shaft hole of 2) is finished by cutting, a gear as shown in Fig. 4 is formed.

As an apparatus for carrying out the method of the present invention, an apparatus as shown in FIG. 8 can be adopted. In this device, the first mold (3a) is suspended from the upper side member (61) of the gate frame (6), and the second mold (3b) is supported by the fixed bed (62) below this. . The first die (3a) is the upper side member (61)
It is attached to the lower surface of the rotary bed (50) in a cylindrical holder (63) that is hung from the bottom and opens downward. The cylindrical holder (63) is a hydraulic cylinder arranged on the upper surface of the upper side member (61).
A pair of guide posts attached to the output shaft of (64) and protruding from the upper surface of the cylindrical holder (63) penetrate the upper side member (61). The rotary bed (50) is rotatably held by a cylindrical holder (63), and a worm wheel (52) formed on the outer peripheral surface of the body and a worm (built in the cylindrical holder (63) ( 53) and a drive motor (not shown) provided in a cylindrical holder (63) through a worm gear device.

Therefore, the first mold (3a) is rotationally driven by the rotation of the drive motor and the hydraulic cylinder (6a).
It is driven up and down by 4). The second mold (3b) has a rotating bed (5) built in a holder (65) attached to a fixed bed (62).
It is mounted on the upper surface of (0), and this rotating bed (50) is
It is rotationally driven by a device (a combination of a worm gear device including a worm wheel (52) and a worm (53) and a drive motor) similar to the rotational drive device of the first mold (3a).

Both the lower surface of the holder (65) and the upper surface of the fixed bed (62) are formed into arcuate curved surfaces, and these arcuate surfaces are in contact with each other. Therefore, the holder (65) can be rotated along this arcuate surface. The center of the arc is the second mold.
It is set at the center of the top surface of (3b). Further, as shown in FIG. 9, side plates (66) (66) provided on both sides of the lower surface of the holder (65) are provided with arcuate recesses (67) concentric with the arcuate surfaces, and the fixed bed (62). The protrusion (68) provided on the side of the
5) is held in a fixed state with respect to the fixed bed (62).

Therefore, the holding posture of the holder (65) can be adjusted by rotating the holder (65) by an appropriate means from the upright posture of the holder (65) shown in FIG. or,
One side plate of the portal frame (6) has a toothed roller.
The supporting device (7) of (4) is provided. This Supporting Device (7)
Is a type in which the tooth forming roller (4) is driven in the horizontal direction by one hydraulic cylinder incorporated therein and is vertically moved by another hydraulic cylinder.

In order to carry out the method of the present invention using the above apparatus, the inclination degree of the second die (3b) is set in advance, and in this state, the material (10) to be processed is placed on the second die (3b). After that, the hydraulic cylinder (64) is driven to lower the first mold (3a) to bring the pressing surface (31) into contact with the material to be processed (10). After this,
Each part is processed in the same manner as in the above-mentioned embodiment.

In any of the above cases, the second mold (3b)
The inclination angle of may be a very small angle. For example, 0.5 degrees
It is set in the range of about 5 degrees. Further, in any of the embodiments, one of the molds is supported in an inclined posture, but as shown in FIG. 10, both the first and second molds (3a) and (3b) are set in the upright posture. Also good.

In this case, the pressure surfaces (31) and (33) of the first and second molds (3a) and (3b) may be symmetrical to each other in order to manufacture the one shown in FIG. In this case as well, between the first and second molds (3a) and (3b), which are symmetrical with each other, between the peripheral edge step parts (31a) and (33a), the molding part of the tooth forming roller (4) is formed as in the above embodiment. (41) may be inserted, but as shown in FIG. 11, the tooth forming roller (4) is in contact with the outer peripheral body of the first and second molds (3a) and (3b) (see FIG. 11). The mold part (41) may be accommodated between the parts (42) and (42). In this case, the first and second molds (3a) (3b)
Has a pressing surface (31) (33) for pressing the range up to the rim portion (11) of the gear shown in FIG.

In each of the above-described embodiments, the manufacture of spur gears has been described, but it goes without saying that it can also be used for manufacture of bevel gears and helical gears. Needless to say, the homogenization of the tooth profile is further improved when hot forging is performed.

[Brief description of drawings]

FIG. 1 is a schematic view of a conventional method for manufacturing a gear by rolling.

[Figure 2] Plan view

FIG. 3 is a sectional view of the completed gear.

FIG. 4 is a sectional view of a gear manufactured according to an embodiment of the present invention.

FIG. 5 is an explanatory diagram of an apparatus used in an embodiment of the present invention.

FIG. 6 is a cross-sectional view showing an intermediate state of steps of the embodiment of the method of the present invention.

FIG. 7 is a sectional view of the final stage

FIG. 8 is an illustration of another apparatus used to carry out the method of the present invention.

FIG. 9 is a sectional view of an essential part of a supporting portion of the fixed bed (65) in this case.

FIG. 10 is an explanatory view when the first and second molds (3a) and (3b) are both upright.

FIG. 11 is an explanatory view of another example of the tooth forming roller (4).

[Explanation of symbols]

 (1a) ・ ・ ・ Disk part (31) ・ ・ ・ Pressing surface (3a) ・ ・ ・ First mold (33) ・ ・ ・ Pressing surface (3b) ・ ・ ・ Second mold (10) ・ ・ ・Work Material (4) ・ ・ ・ Toothed roller

Claims (1)

[Claims] 1. A method for manufacturing a gear in which a disk part (1a) and a tooth profile part (1b) formed on the outer periphery of the disk part (1a) are integrally formed from a workable material (10) capable of being plastically processed. 1
a) Pressing surface of the first mold (3a) matching the shape of one side surface of a)
(31) and the pressing surface (33) of the second mold (3b) that matches the other side surface shape of the disk portion (1a) are opposed to each other, and the boundary portion between the pressing surfaces (31) and (33) A tooth forming roller (4) is movably arranged on the outer circumference, and the material to be processed (1) is placed between the pressure surfaces (31) and (33).
0) is interposed and the first and second parts are synchronously rotated in the same direction.
・ The disk part (1a) is molded by pressing the second molds (3a) (3b) in the axial direction, and the mold part (41) on the outer periphery of the tooth forming roller (4) in the mold rotating state. The pressure surface (3
1) A manufacturing method of a gear in which the tooth profile portion (1b) is molded by applying pressure to the peripheral portion extended from between (33).