JP3634958B2 - Manufacturing method of shaft member with drum and shaft member with drum - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
TECHNICAL FIELD The present invention relates to a method of manufacturing a shaft member with a drum in which a drum having internal teeth is fixed to a shaft member such as an input shaft and a clutch drum of an automatic transmission, and a technical field of a shaft member with a drum manufactured by the method. Belonging to.
[0002]
[Prior art]
Conventionally, automotive transmission parts (shaft members with drums) represented by input shafts, etc., as shown in Fig. 5, shaft parts with oil holes and spline teeth use carburized heat-treated parts or induction-hardened parts. The outer peripheral clutch drum part is manufactured by using a sheet metal press part and joining the shaft part part and the clutch drum part by electron beam welding.
[0003]
[Problems to be solved by the invention]
However, in the conventional method for manufacturing a transmission part for an automobile, a shaft member with a drum is manufactured by separately manufacturing a shaft part part and a clutch drum part which are independent from each other, and joining both parts by electron beam welding. Therefore, there are problems listed below.
[0004]
(1) Machining of shaft parts (oil holes and spline teeth) and heat treatment, press molding and machining of clutch drum parts (holes, grooves and finishing), and electron beam welding work while aligning both parts Therefore, the manufacturing time becomes long and the manufacturing cost becomes expensive.
[0005]
(2) When carburizing heat treatment is performed on shaft parts, blowholes, pinholes, cracks, etc. occur during electron beam welding due to poor carburization prevention of the welded portion, and desired welding strength cannot be obtained.
[0006]
(3) We must rely on cutting surveys to check the welding quality, and it is impossible to actually check the welding quality of all products. Therefore, in order to maintain high welding quality, it is necessary to spend time while paying close attention during welding work.
[0007]
(4) Since the shaft object part and the clutch drum part are electron beam welded, welding distortion caused by material heating accompanying welding cannot be avoided, the spline teeth are inclined due to welding distortion, and the shaft of the shaft object part and the clutch drum part is The fitting gap with the clutch plate cannot be kept constant due to misalignment.
[0008]
(5) In order to increase the strength of a separate clutch drum, only the clutch drum needs to be soft-nitrided.
[0009]
In the above conventional manufacturing method, the method of manufacturing the clutch drum part by press molding has been described. However, as described in JP-A-7-51781, the clutch drum part is processed by cold rotational plastic working. A method of processing by forming is known. In this flow forming, a material is set in a mold, the material is rotated together with the mold, the forming roller is moved relatively along the mold while keeping the pressure of the forming roller against the drum portion, and is extruded by ironing with the roller. It refers to cold rotational plastic working in which the material is poured into a mold and a drum having internal teeth is formed.
[0010]
Therefore, when this flow forming is adopted for drum production, there is no spring back in the elastic deformation region as in press molding, and spline inner teeth can be molded with high accuracy equivalent to machining accuracy, and cold plastic working For this reason, there is a merit that the mechanical properties (tensile strength / toughness / fatigue strength) are higher than the material strength because the work flow is large and the fiber flow phenomenon such as landslide and miniaturization of metal structure crystals is utilized. is there.
[0011]
However, since there is no change in manufacturing a shaft member with a drum by welding a drum manufactured by flow forming and a shaft object part, the above problems (1) to (4) are not solved at all. Not.
[0012]
The problem to be solved by the present invention is to achieve both high precision and high strength while achieving low manufacturing costs, ensuring high product quality, preventing tooth tilt and preventing the shaft axis from shifting. An object of the present invention is to provide a method of manufacturing a shaft member with a drum integrally having a drum and a shaft member with a drum.
[0013]
[Means for Solving the Problems]
(Solution 1)
The solution 1 (Claim 1) of the above-mentioned problem uses a single material having a shaft member and a disc-shaped drum portion, and processes oil holes and spline teeth on the shaft member and extends the drum portion by forging. Machining process to make preform shape of rotary plastic processing,
A carburizing and quenching process for forming a carburized hardened layer on the entire surface of the machined material;
A heat annealing step in which only the drum portion subjected to rotational plastic working among the quenched materials is subjected to heat annealing to make the hardness capable of rotational plastic working, and
Cold rotating plasticity that molds a drum with internal teeth by setting a mold on the drum part that has been heat-annealed and moving the forming roller relative to the mold part while keeping the pressing of the forming roller against the drum part Processing steps,
It is characterized by having.
[0014]
In this case, it is desirable to rotate the material together with the mold. By rotating the material together with the mold, it becomes easy to control the rotational plastic working process, and the accuracy of the internal teeth can be improved.
[0015]
(Solution 2)
Means for solving the problem 2 (Claim 2) is the method of manufacturing a shaft member with a drum according to Claim 1,
The heat annealing step is a step of performing heat annealing in a vacuum or an inert gas such as nitrogen.
[0016]
(Solution 3)
The solution 3 (Claim 3) of the above-mentioned problem is the method of manufacturing a shaft-attached shaft member according to Claim 1 or Claim 2,
The heating annealing step is a step of raising the workpiece temperature to a set annealing temperature level and maintaining the workpiece temperature raised to a time at which the hardness distribution of the annealing portion can be made uniform by heating and holding.
[0017]
(Solution 4)
Means for solving the above problem 4 (Claim 4) is the method of manufacturing a shaft member with a drum according to Claims 1 to 3,
The heat annealing process is characterized in that the Vickers hardness after annealing is set to HV100 to 150, and the annealing conditions are such that the Vickers hardness after rotational plastic working can ensure HV230 or more.
[0018]
(Solution 5)
Solving means 5 (Claim 5) of the above-mentioned problem is a shaft member with a drum in which a drum having internal teeth is fixed to a shaft member having oil holes, spline teeth, etc.
The shaft member and the drum are integrated with a single material,
The shaft member is a member having a carburized hard layer formed on the surface,
The drum is a member having internal teeth by rotational plastic working.
[0019]
(Solution 6)
The means for solving the above problem 6 (Claim 6) is a shaft member with a drum according to Claim 5,
The shaft member is a shaft for transmitting power provided in an automatic transmission,
The drum is a clutch drum that rotates integrally with a shaft and in which a clutch plate is slidably fitted to an internal tooth.
[0020]
DETAILED DESCRIPTION OF THE INVENTION
(Embodiment 1)
The first embodiment is a method of manufacturing a shaft member with a drum corresponding to the inventions according to claims 1 to 4 and a shaft member with a drum corresponding to the inventions according to claims 5 and 6.
[0021]
[About manufacturing method of shaft member with drum]
FIG. 1 is a process explanatory view showing a manufacturing method of a shaft member with a drum according to the first embodiment. In FIG. 1, 1 is a shaft member, 2 is a drum, 2 ′ is a drum portion, 3a is a first shaft center oil hole, 3b is a second shaft oil hole, 4 is a spline tooth, 5 is a spline internal tooth, 6 is a carburized hardened layer, 7 is a mold, and 8 is a forming roller. And the manufacturing method of the shaft-attached shaft member of Embodiment 1 is based on a machining process, a carburizing and quenching process, a heat annealing process, and a rotational plastic working process. Each process will be described below.
[0022]
In the machining process, as shown in FIG. 1 (a), a single material having a shaft member 1 and a disc-shaped drum portion 2 ′ is used, and as shown in FIG. 1 (b), the shaft member 1 In addition, the first shaft oil hole 3a, the second shaft oil hole 3b, and the spline teeth 4 are machined, and the drum portion 2 'is extended by swing forging to form a preform for flow forming (an example of rotational plastic machining). .
[0023]
In the carburizing and quenching step, as shown in FIG. 1 (c), carburizing and quenching is performed on the machined material to form a carburized hardened layer 6 on the entire surface.
[0024]
In the heating and annealing process, as shown in FIG. 1 (d), only the drum portion 2 ′ of the quenched material to be subjected to flow forming is subjected to high-frequency heating (basically, high-frequency heating is performed, but laser heating can be used instead. To a hardness that can be flow-formed by annealing (Vickers hardness is HV100 to 150). In this heating annealing step, the portion of the shaft member 1 below the one-dot chain line in FIG. Further, as far as the portion of the drum portion 2 'to be heat-annealed, it is assumed that a predetermined margin is taken from the iron portion by flow forming.
[0025]
In the rotational plastic working process, as shown in FIG. 1 (e), a mold 7 is set on the heat-annealed drum part 2 ′, the material is rotated together with the mold 7, and the forming roller 8 is moved relative to the drum part 2 ′. Cold rotating plastic working for forming the drum 2 having the spline internal teeth 5 by moving the forming roller 8 relative to the die 7 while keeping the pressure (moving the die 7 and the material in the axial direction). Do. In addition, since a material having a high initial hardness of the workpiece is formed as compared with a flow forming apparatus that performs flow forming using hot-rolled or cold-rolled steel as a material, the flow forming apparatus to be used is the mold 7 The overall system configuration is designed to increase strength (wear resistance, fatigue resistance, impact resistance) and rigidity including equipment.
[0026]
[About heat annealing process]
In the heating annealing step, the following heating annealing conditions are given.
[0027]
(1) In the heat annealing step, heat annealing is performed in vacuum or in an inert gas such as nitrogen in order to prevent adhesion of oxide scale.
[0028]
(2) The heating annealing process takes a long heating holding time in order to make the hardness distribution uniform. That is, pulsing heating is employed. Further, by this pulsing heating, the carburized and quenched structure is changed to ferrite + pearlite structure, and cementite in the pearlite structure is spheroidized as much as possible to facilitate the rotational plastic workability in the subsequent process. Specifically, the workpiece temperature is raised to the set annealing temperature level (450 ° C. to 950 ° C.) and not immediately lowered as shown by the dotted line characteristics in FIG. 2, but as shown by the solid line characteristics in FIG. The raised workpiece temperature is maintained for a predetermined time.
[0029]
(3) The heat annealing step is performed under an annealing condition in which the Vickers hardness after annealing is set to a hardness capable of rotational plastic working of HV100 to 150, and the Vickers hardness after rotational plastic working is capable of ensuring HV230 or more.
[0030]
[About shaft member with drum]
FIG. 3 is a cross-sectional view showing the drum-equipped shaft member A according to the first embodiment. In FIG. 3, 1 is a shaft member, 2 is a drum, 3a is a first shaft oil hole, 3b is a second shaft oil hole, 3c is a first radial oil hole, 3d is a second radial oil hole, 4 is a spline tooth, 5 is a spline internal tooth, and 6 is a carburized hardened layer.
[0031]
As shown in FIG. 3, the shaft member A with a drum manufactured by the above manufacturing method includes a drum 2 having spline inner teeth 5 on a shaft member 1 having oil holes 3a, 3b, 3c, 3d, spline teeth 4, and the like. The shaft member 1 and the drum 2 are fixed members, and the shaft member 1 is a member in which the carburized hardened layer 6 is formed on the surface, and the drum 2 is a rotational plastic working. This is a member having a highly accurate spline internal tooth 5.
[0032]
[Automatic transmission to which a shaft member with a drum is applied]
FIG. 4 is a cross-sectional view showing a power transmission mechanism of an automatic transmission to which a drum-equipped shaft member A manufactured by the manufacturing method of Embodiment 1 is applied.
[0033]
4, 10 is an input shaft (shaft member with drum), 11 is a torque converter, 12 is a converter housing, 13 is an oil pump, 14 is a reverse clutch, 15 is a brake band, 16 is a high clutch, and 17 is a front planetary. Gear, 18 is a low one-way clutch, 19 is a rear planetary gear, 20 is a forward clutch, 21 is an overrun clutch, 22 is a low and reverse brake, 23 is an output shaft, 24 is an output gear, 25 is an idler gear, and 26 is a forward A one-way clutch, 27 is a pinion reduction gear, 28 is a final gear, and 29 differential.
[0034]
In this automatic transmission, two sets of planetary gears 17 and 19 are used, and four sets of clutches 14, 16, 20 and 21, two sets of brakes 15 and 22, and two sets of one-way clutches 18 and 26 are combined. , 4 forward speed and 1 reverse speed are performed.
[0035]
The input shaft 10 is a shaft that transmits engine power input through the torque converter 11, and a high clutch drum that is provided integrally with the input shaft 10 and rotates integrally with the spline inner teeth of the clutch plate. Are slidably fitted.
[0036]
Next, the function and effect will be described.
[0037]
[Production cost]
The manufacturing cost of the drum-equipped shaft member A is reduced by replacing the separate product with an integrated product and manufacturing it as an integrally molded product by flow forming. That is, the manufacturing cost is reduced by omitting a welding process that requires careful work for ensuring quality and accuracy.
[0038]
Further, by adopting the carburizing quenching method as the entire quenching method in the case of an integrally molded product, the cost can be reduced as compared with the case where the induction quenching method is employed. This is because when the induction hardening method is employed, two shaft quenching steps are required, and the manufacturing process becomes complicated and expensive.
[0039]
[Product quality]
In the case of a conventional manufacturing method by separate parts welding, blowholes, pinholes, cracks, etc. occur during electron beam welding due to poor carburization prevention of the welded parts of shaft parts, and the desired welding strength cannot be obtained. However, there is a problem that the welding quality confirmation work must be relied on cutting surveys, and there is a problem that the welding quality cannot actually be confirmed. When mass production is performed, stable high product quality without variation cannot be expected.
[0040]
On the other hand, since the drum-equipped shaft member A is an integral product without welding, there are no blowholes, pinholes, cracks, etc. during electron beam welding. Guarantees stable and high product quality without variation.
[0041]
[Product accuracy]
In the case of the conventional manufacturing method by separate parts welding, the shaft parts and the clutch drum parts are electron beam welded. Therefore, it is impossible to avoid welding distortion caused by material heating accompanying welding, and spline teeth are inclined due to welding distortion. The fitting gap with the clutch plate cannot be kept constant due to the misalignment of the axis between the parts and the clutch drum parts.
[0042]
On the other hand, the shaft member A with a drum is formed by integrating the shaft member 1 and the drum 2 and the drum 2 is formed by flow forming, so that there is no distortion or axial misalignment caused by welding, and tooth inclination is prevented. In addition, axial misalignment between the shaft member 1 and the drum 2 is prevented. Moreover, in the flow forming performed while rotating together with the mold 7, the machining accuracy of the spline inner teeth 5 of the drum 2 is as high as that of machining, and the axial center coincidence with the shaft member 1 is high, and the tooth blur quality is high. Absolutely improved.
[0043]
In the manufacturing method of the first embodiment, the carburizing heat treatment is performed prior to the flow forming. However, if the carburizing heat treatment is performed in a subsequent process, the clutch drum is deformed due to heat treatment distortion, which is required. This is because the dimensional accuracy cannot be satisfied.
[0044]
[About product strength]
In the case of the conventional manufacturing method using separate parts welding, only a separate clutch drum is subjected to soft nitriding in order to increase the strength.
[0045]
On the other hand, in the first embodiment, after the carburizing and quenching, by providing a heating annealing process for only the drum portion 2 ', the required hardness of the drum 2 and the required strength can be freely selected. In addition, by forming the drum 2 by flow forming, it is possible to enjoy the advantages of increased work hardening by cold plastic working and improved material strength by fiber flow.
[0046]
Accordingly, the strength of the shaft portion 1 can be increased by induction hardening, and the strength of the drum 2 can be increased without performing a soft nitriding treatment.
[0047]
In addition, when the induction hardening method is adopted as the whole hardening method, the core hardness of the shaft portion cannot be improved, and it is unavoidable to cope with the increase in strength.
[0048]
(Other embodiments)
In the first embodiment, the application example to the input shaft of the automatic transmission is shown. However, the manufacturing method of the present invention can be applied as long as the shaft member and the drum are integrally provided.
[0049]
【The invention's effect】
In the manufacturing method of the shaft-attached shaft member according to claim 1, a single material having the shaft member and the disc-shaped drum portion is used, and an oil hole and a spline tooth are processed in the shaft member and the drum portion Is machined by forging to form a preform shape for rotational plastic processing, carburizing and quenching for forming a carburized hardened layer on the entire surface of the machined material, and rotational plastic processing of the quenched material. Set the mold to the heat-annealing process to heat-anneal only the drum part and make it possible for rotational plastic processing, and the heat-annealed drum part, and keep the pressing of the forming roller against the drum part to the mold And a cold rotational plastic forming process for forming a drum having internal teeth by relatively moving the forming roller along the line, so that low manufacturing costs and high product quality can be ensured. And prevention can, while achieving prevention of axial displacement of the drum, the drum having both high accuracy and high strength can be provided a method for manufacturing the drum shank member which integrally.
[0050]
In addition, when a raw material is rotated with a metal mold | die in a rotational plastic processing process, process control becomes easy and the precision of an internal tooth can be improved.
[0051]
In the invention of claim 2, in the method of manufacturing the drum-equipped shaft member according to claim 1, the heat annealing step is a step of performing heat annealing in vacuum or in an inert gas such as nitrogen, In addition to the effects of the first aspect of the invention, it is possible to prevent adhesion of oxide scale during heat annealing.
[0052]
According to a third aspect of the present invention, in the method for manufacturing a drum-equipped shaft member according to the first or second aspect, in the heat annealing step, the workpiece temperature is increased to a set annealing temperature level, and the annealing portion is performed by heating and holding. In addition to the effect of the invention according to claim 1 or 2, in addition to the effect of the invention according to claim 1, it is possible to facilitate the subsequent rotary plastic working step. .
[0053]
In the invention according to claim 4, in the method of manufacturing a shaft member with a drum according to claim 1 to claim 3, the heat annealing step is performed so that the Vickers hardness after annealing is HV100 to 150, and rotational plastic working is performed. Since the subsequent Vickers hardness is an annealing condition that can ensure HV230 or more, in addition to the effects of the inventions of claims 1 to 3, the product has a high hardness while ensuring a rotational plastic working hardness. The drum hardness can be ensured.
[0054]
In the invention according to claim 5, in the shaft member with the drum in which the drum having the inner teeth is fixed to the shaft member having the oil hole, the spline teeth, etc., the shaft member and the drum are integrally formed of a single material. In addition, the shaft member is a member having a carburized hard layer formed on the surface, and the drum is a member having internal teeth by rotational plastic processing, so that low manufacturing costs, high product quality, and tooth inclination are achieved. It is possible to provide a drum member with a drum that integrally has a drum that achieves both high accuracy and high strength while achieving prevention and prevention of misalignment of the axis of the drum.
[0055]
According to a sixth aspect of the present invention, in the shaft member with a drum according to the fifth aspect, the shaft member is a shaft for transmitting power provided in the automatic transmission, and the drum rotates integrally with the shaft. Since the clutch drum is slidably fitted to the teeth, the clutch plate can move smoothly along the inner teeth when the clutch is engaged / released. Dragging and uneven plate wear are prevented, and the durability and reliability of the clutch can be improved.
[Brief description of the drawings]
FIG. 1 is a process diagram illustrating a manufacturing method of a shaft-equipped shaft member according to a first embodiment.
FIG. 2 is a workpiece temperature characteristic diagram in a heating annealing step of the manufacturing method of the drum-equipped shaft member according to the first embodiment.
FIG. 3 is a cross-sectional view showing the drum member with the drum according to the first embodiment;
4 is a cross-sectional view showing a power transmission mechanism of an automatic transmission to which a drum-equipped shaft member manufactured by the manufacturing method of Embodiment 1 is applied. FIG.
FIG. 5 is a cross-sectional view showing a conventional shaft member with a drum.
[Explanation of symbols]
A shaft member with drum 1 shaft member 2 drum 2 'drum portion 3a first shaft oil hole 3b second shaft oil hole 3c first radial oil hole 3d second radial oil hole 4 spline teeth 5 spline inner teeth 6 Carburized hardened layer 7 Mold 8 Forming roller 10 Input shaft (shaft member with drum)

Claims (6)

A machining process that uses a single material having a shaft member and a disk-shaped drum portion, processes oil holes and spline teeth on the shaft member, and stretches the drum portion by forging to form a preform shape for rotational plastic processing; ,
A carburizing and quenching process for forming a carburized hardened layer on the entire surface of the machined material;
A heat annealing step in which only the drum portion subjected to rotational plastic working among the quenched materials is subjected to heat annealing to make the hardness capable of rotational plastic working; and
Cold rotating plasticity that molds a drum with internal teeth by setting a mold in the drum section that has been heat-annealed and moving the forming roller relative to the mold section while keeping the forming roller pressed against the drum section Processing steps,
The manufacturing method of the shaft-attached shaft member characterized by the above-mentioned. In the manufacturing method of the shaft-attached shaft member according to claim 1,
The method for manufacturing a drum-equipped shaft member, wherein the heat annealing step is a step of performing heat annealing in a vacuum or an inert gas such as nitrogen. In the manufacturing method of the shaft-attached shaft member according to claim 1 or 2,
A shaft with a drum characterized in that the heating annealing step is a step of raising the workpiece temperature to a set annealing temperature level and maintaining the workpiece temperature raised to a time at which the hardness distribution of the annealing portion can be made uniform by heating and holding. Manufacturing method of member. In the manufacturing method of the shaft-attached shaft member according to claim 1 to 3,
The shaft-with-drum member characterized in that the heating annealing step is an annealing condition in which a Vickers hardness after annealing is set to HV100 to 150, and a Vickers hardness after rotational plastic working can ensure HV230 or more. Production method. In a shaft member with a drum in which a drum having internal teeth is fixed to a shaft member having oil holes, spline teeth, etc.,
The shaft member and the drum are integrated with a single material,
The shaft member is a member having a carburized hard layer formed on the surface,
The drum is a shaft member with a drum, wherein the drum is a member having internal teeth by rotational plastic working. In the shaft member with a drum according to claim 5,
The shaft member is a shaft for transmitting power provided in an automatic transmission,
A drum member with a drum drum, wherein the drum is a clutch drum that rotates integrally with a shaft and in which a clutch plate is slidably fitted to an internal tooth.

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