JPH11267780A - Shaft member with drum and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a shaft member with an integrated drum having high precision and strength, and to provide its manufacturing method which ensures low manufacturing cost and high product quality as well as preventing teeth from tilting and the shaft center of the drum from shifting. SOLUTION: This manufacturing method consists of a carburizing and hardening process that forms a carburized cemented layer 6 on the entire surface of a machined base material in which a shaft 1 and a drum 2' are integrated; a heating and annealing process that heats and anneals only the drum 2' on which rotary plastic working is applied among the hardened base materials and that brings such hardness as to enable rotary plastic working; and a cold rotary plastic working process that forms the drum 2 possessing a internal tooth 5 by setting a metallic die 7 in the heated annealed drum 2', rotating the base material together with the die 7, and relatively moving a forming roller 8 along the die 7 while the pressurization of the forming roller 8 is maintained against the drum 2'. A bearing member A with a drum is manufactured by the above method.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention 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 the shaft member, such as an input shaft and a clutch drum of an automatic transmission, and a method of manufacturing the same. It belongs to the technical field of a shaft member with a drum.

[0002]

2. Description of the Related Art Conventionally, transmission parts for automobiles (shaft members with drums) represented by input shafts and the like are, as shown in FIG. 5, shaft parts having oil holes and spline teeth are carburized heat treated products or high-frequency parts. A quenched part is used, and a clutch drum part on the outer peripheral part is manufactured by using a sheet metal pressed part and joining a shaft part part and a clutch drum part by electron beam welding.

[0003]

However, in the above-mentioned conventional method of manufacturing a transmission part for an automobile, a shaft part and a clutch drum part which are independent from each other are manufactured separately, and both parts are joined by electron beam welding. By doing so, we are manufacturing a shaft member with a drum,
There are problems listed below.

(1) Machining of shaft parts (oil holes and spline teeth) and heat treatment, and press forming and machining of clutch drum parts (holes, grooves and finishes), and electronic positioning of both parts And the beam welding work must be performed respectively, so that the production time is enormous,
Manufacturing costs are also high.

(2) When a shaft part is subjected to carburizing heat treatment, blowholes, pinholes, cracks, etc. occur during electron beam welding due to poor carburization prevention of a welded portion, and a desired welding strength cannot be obtained. .

(3) In order to check the welding quality, it is necessary to rely on a cutting survey, and it is not possible to actually check the welding quality of all products. Therefore, in order to maintain high welding quality, it is necessary to take time while paying close attention to the welding operation.

(4) Since the shaft part and the clutch drum part are subjected to electron beam welding, welding distortion caused by material heating during welding cannot be avoided, and the spline teeth are inclined due to the welding distortion, and the shaft part and the clutch drum part. , The fitting gap with the clutch plate cannot be kept constant.

(5) In order to increase the strength of the separate clutch drum, it is necessary to perform a soft nitriding treatment only on the clutch drum.

In the above-described conventional manufacturing method, a method of manufacturing a clutch drum part by press molding has been described. However, as described in Japanese Patent Application Laid-Open No. 7-51781, a clutch drum part is formed by cold rotary plastic working. There is known a method of processing by flow forming. In this flow forming, the material is set in the mold, the material is rotated together with the mold, the forming roller is relatively moved along the mold while keeping the pressing of the forming roller against the drum portion, and the material is pushed out by ironing with the roller. This is a cold rotational plastic working method in which the poured material is poured into a mold to form a drum having internal teeth.

Therefore, when this flow forming is adopted in the production of a drum, there is no springback in the elastic deformation region as in press molding, and the spline teeth can be formed with high precision equivalent to the machining precision. Work hardening is large due to plastic working, and fiber flow phenomena such as landslide and miniaturization of metal structure crystals are utilized, so mechanical properties (tensile strength, toughness, fatigue strength) are higher than material strength There is an advantage.

However, since there is no difference in manufacturing a shaft member with a drum by welding a drum manufactured by flow forming and a shaft component, the above problems (1) to (4) are solved. Is not resolved at all.

The problem to be solved by the present invention is to achieve high precision and high strength while achieving low manufacturing cost, high product quality, prevention of tooth inclination and prevention of axial misalignment of the drum. An object of the present invention is to provide a method of manufacturing a shaft member with a drum integrally having a compatible drum and a shaft member with a drum.

[0013]

[Means for Solving the Problems] [Solution 1] Solution 1 of the above problem (Claim 1) uses a single material having a shaft member and a disk-shaped drum portion, and uses oil for the shaft member. Machining process for forming holes and spline teeth and forging the drum part by forging to form a preform of rotational plastic working, carburizing and quenching process for forming a carburized hardened layer on the entire surface of the machined material, and quenching Of the finished material, heat-annealing only the drum part to be subjected to rotational plastic working to make it hard enough to perform rotational plastic working, and setting a mold on the heated and annealed drum part and forming the drum part A cold rotational plastic working step of forming a drum having internal teeth by relatively moving the forming roller along the mold while keeping the pressure of the roller.

In this case, it is desirable to rotate the material together with the mold. By rotating the material together with the mold, the control of the rotational plastic working process is facilitated, and the accuracy of the internal teeth can be improved.

(Solution 2) A method for manufacturing a shaft member with a drum according to claim 1, wherein the heating and annealing step is performed in a vacuum or with an inert gas such as nitrogen. A step of performing heat annealing in the inside.

According to a third aspect of the present invention, in the method of manufacturing a shaft member with a drum according to the first or second aspect, the heat annealing step is performed at a predetermined annealing temperature level. The process is characterized in that the temperature of the workpiece is raised to a time at which the hardness distribution of the annealed portion can be made uniform by heating and maintaining the temperature of the workpiece.

(Solution 4) According to a fourth aspect of the present invention, in the method for manufacturing a shaft member with a drum according to any one of the first to third aspects, the heating and annealing step is performed by a method comprising: Are HV100-150, and
The annealing conditions are such that the Vickers hardness after rotational plastic working is HV230 or more.

(Solution 5) A fifth aspect of the present invention provides a shaft member with a drum in which a drum having internal teeth is fixed to a shaft member having an oil hole, spline teeth, or the like. The drum and the drum are made of a single material, and the shaft member is a member having a carburized hardened layer formed on the surface thereof, and the drum is a member having internal teeth formed by rotational plastic working. I do.

(Solution 6) In a sixth solution of the present invention, in the shaft member with a drum according to the fifth invention, the shaft member is a shaft provided in an automatic transmission for transmitting power. The drum is a clutch drum which rotates integrally with the shaft and has a clutch plate slidably fitted to the internal teeth.

[0020]

(Embodiment 1) Embodiment 1 corresponds to a method of manufacturing a shaft member with a drum corresponding to the inventions of claims 1 to 4, and to the inventions of claims 5 and 6. It is a shaft member with a drum.

[Regarding Method of Manufacturing Shaft Member with Drum]
FIG. 1 is a process explanatory view showing a method for manufacturing 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 oil hole, 3b is the second
Shaft center oil hole, 4 is spline teeth, 5 is spline internal teeth, 6
Is a carburized hardened layer, 7 is a mold, and 8 is a forming roller. The method of manufacturing the shaft member with a drum according to the first embodiment includes a machining step, a carburizing and quenching step, a heating annealing step, and a rotational plastic working step. Each step will be described below.

In the machining step, 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. First on shaft member 1
The shaft center oil hole 3a, the second shaft center oil hole 3b, and the spline teeth 4 are machined, and the drum part 2 'is stretched by swing forging to obtain a preform shape for flow forming (an example of rotational plastic working).

In the carburizing and quenching step, as shown in FIG. 1C, the machined material is carburized and quenched to form a carburized hardened layer 6 on the entire surface.

In the heat annealing step, as shown in FIG. 1D, 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 as an alternative, A hardness (Vickers hardness: HV 100 to 150) at which flow forming can be performed by annealing by laser heating is also possible. In the heat annealing step, the portion of the shaft member 1 below the one-dot chain line in FIG. The portion of the drum portion 2 'to be heated and annealed is a portion which has a predetermined margin from the stiff portion by flow forming.

In the rotational plastic working step, as shown in FIG. 1 (e), a mold 7 is set on the heated and annealed drum 2 ',
By rotating the material together with the mold 7 and relatively moving the forming roller 8 along the mold 7 (moving the mold 7 and the material in the axial direction) while keeping the pressing of the forming roller 8 against the drum portion 2 ′. A cold rotational plastic working for forming the drum 2 having the spline internal teeth 5 is performed. Since a material having a high initial hardness of a workpiece is formed as compared with a flow forming apparatus that performs flow forming using a hot-rolled or cold-rolled steel strip as a material, the flow forming apparatus to be used is Strength (wear, fatigue,
The overall system configuration is designed to increase rigidity including impact resistance and equipment.

[About Heat Annealing Step] In the above heat annealing step, the following heat annealing conditions are given.

(1) In the heat annealing step, heat annealing is performed in a vacuum or in an inert gas such as nitrogen in order to prevent adhesion of oxide scale.

(2) In the heat annealing step, the heating and holding time is extended to make the hardness distribution uniform. That is, pulsing heating is employed. In addition, by this pulsing heating,
Carburized and quenched structure to ferrite + pearlite structure,
The cementite in the pearlite structure is pseudo-spheroidized as much as possible, and facilitates rotational plastic workability in a subsequent step. Specifically, the set annealing temperature level (450 ° C. to 950
The temperature of the workpiece is not immediately lowered as shown by the dotted line in FIG. 2 and the workpiece temperature is maintained for a predetermined time as shown by the solid line in FIG.

(3) In the heat annealing step, 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 HV23.
Annealing conditions that can ensure 0 or more are set.

[Shaft Member with Drum] FIG. 3 is a sectional view showing a shaft member A with a drum according to the first embodiment. In FIG. 3, 1 is a shaft member, 2 is a drum, and 3a is a first shaft oil hole. 3b is a second axial 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.

As shown in FIG. 3, the shaft member A with a drum manufactured by the above-described manufacturing method has oil holes 3a, 3b, 3b.
A drum 2 having spline internal teeth 5 is fixed to a shaft member 1 having c, 3d, spline teeth 4 and the like. The shaft member 1 and the drum 2 are integrally formed of a single material, 1 is a member having a carburized hardened layer 6 formed on the surface, and the drum 2 is a member having high-precision spline teeth 5 formed by rotational plastic working.

FIG. 4 is a sectional view showing a power transmission mechanism of an automatic transmission to which the shaft member with drum A manufactured by the manufacturing method of the first embodiment is applied. FIG.

In FIG. 4, reference numeral 10 denotes an input shaft (a shaft member with a drum); 11, a torque converter;
Is a converter housing, 13 is an oil pump, 14 is a reverse clutch, 15 is a brake band, 16 is a high clutch, 17 is a front planetary gear, 18 is a low one-way clutch, 19 is a rear planetary gear, 2
0 is a forward clutch, 21 is an overrun clutch, 22 is a low & reverse brake, 23 is an output shaft, 24 is an output gear, 25 is an idler gear, 26 is a forward one-way clutch, 27 is a pinion reduction gear, and 28 is final gear. , 2
9 differentials.

In this automatic transmission, two sets of planetary gears 17, 19 are used, and four sets of clutches 14, 16,
A combination of 20, 21, two sets of brakes 15, 22, and two sets of one-way clutches 18, 26 allows four forward speeds and one reverse speed.

The input shaft 10 is a shaft for transmitting engine power inputted through the torque converter 11. The high clutch drum provided integrally with the input shaft 10 and rotating integrally therewith has a spline internal tooth. The clutch plate is slidably fitted to the clutch plate.

Next, the function and effect will be described.

[Manufacturing Cost] The manufacturing cost of the shaft member A with a drum can be reduced by replacing the separate product with an integrated product and manufacturing it as an integrated product by flow forming. That is, the manufacturing cost is reduced by omitting a welding process that requires careful work to ensure quality and accuracy.

Further, by adopting the carburizing and quenching method as the whole quenching method when forming an integrally molded product, the cost can be reduced as compared with the case of employing the induction quenching method. This is because, if the induction hardening method is adopted, two shaft hardening steps are required, and the manufacturing process becomes complicated and costly.

[Product quality] In the case of the conventional manufacturing method using separate component welding, blowholes, pinholes, cracks, and the like occur during electron beam welding due to poor carburization prevention of the welded portion of the shaft component. The welding strength cannot be obtained or the welding quality must be checked by cutting surveys.Therefore, there is a problem that the welding quality cannot be checked in actuality. Can't hope for product quality.

On the other hand, since the shaft member A with the drum is a welding-less integral product, there is no blowhole, pinhole, crack or the like at the time of electron beam welding, and there is no need to check the welding quality. Quality is absolutely guaranteed, and stable and high product quality without variation is secured.

[Product Accuracy] In the case of the conventional manufacturing method using separate component welding, since the shaft component and the clutch drum component are subjected to electron beam welding, welding distortion caused by material heating accompanying welding cannot be avoided. As a result, the spline teeth are inclined, and the fitting gap between the clutch plate and the clutch plate cannot be kept constant due to the axial center misalignment between the shaft component and the clutch drum component.

On the other hand, in the shaft member A with the drum, the shaft member 1 and the drum 2 are integrated, and since the drum 2 is formed by flow forming, there is no distortion or shaft misalignment due to welding and the inclination of the teeth. Is prevented, and the shaft center deviation 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 processing accuracy of the spline internal teeth 5 of the drum 2 is as high as that of the mechanical processing, and the shaft center coincidence with the shaft member 1 is high, and the tooth runout quality is improved. Absolutely improve.

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 the heat treatment distortion. This is because the required dimensional accuracy cannot be satisfied.

[Regarding Product Strength] In the case of the conventional manufacturing method using separate parts welding, only a separate clutch drum was subjected to nitrocarburizing treatment in order to increase strength.

On the other hand, in the first embodiment, after the carburizing and quenching, a heating and annealing step for only the drum portion 2 ′ is provided, so that the required hardness of the drum 2 and thus 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 increasing work hardening due to cold plastic working and improving material strength due to fiber flow.

Therefore, the strength of the shaft portion 1 can be enhanced by induction hardening, and the strength of the drum 2 can be enhanced without performing nitrocarburizing treatment.

When the induction hardening method is adopted as the overall hardening method, the hardness of the core of the shaft cannot be improved, and a very severe result must be obtained in order to cope with high strength. .

(Other Embodiments) In the first embodiment, an example in which the present invention is applied to an input shaft of an automatic transmission has been described. The method can be applied.

[0049]

According to the method for manufacturing a shaft member with a drum according to the first aspect, a single material having a shaft member and a disk-shaped drum portion is used, and an oil hole or a spline tooth is formed in the shaft member. Machining process to form a preform of rotational plastic working by processing and stretching the drum part by forging, carburizing and quenching process to form a carburized hardened layer on the entire surface of the machined material, and rotation of the quenched material Heat-annealing only the drum part to be subjected to plastic working to a hardness that enables rotational plastic working, and setting a mold on the heat-annealed drum part to keep the pressing of the forming roller against the drum part. A cold rotational plastic working process of forming a drum having internal teeth by relatively moving the forming roller along the mold while keeping the mold, so low production costs and high product quality And securing, and inclination prevention of tooth, 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.

In the rotational plastic working step, when the material is rotated together with the mold, the working control is facilitated and the precision of the internal teeth can be improved.

According to the second aspect of the present invention, a first aspect is provided.
In the method for manufacturing a shaft member with a drum according to the above aspect, the heat annealing step is a step of performing the heat annealing in a vacuum or an inert gas such as nitrogen. Of the oxide scale can be prevented.

According to the third aspect of the present invention, there is provided the first aspect.
3. The method of manufacturing a shaft member with a drum according to claim 2, wherein the heating and annealing step is performed by increasing the work temperature to a set annealing temperature level and increasing the work temperature to a time at which the hardness distribution of the annealed portion can be made uniform by heating and holding. Therefore, in addition to the effects of the invention described in claim 1 or 2, the subsequent rotational plastic working step can be facilitated.

In the invention according to claim 4, claim 1 is
4. The method for manufacturing a shaft member with a drum according to claim 3, wherein the heat annealing step is performed by setting the Vickers hardness after annealing to HV.
Since the annealing conditions are set to 100 to 150 and the Vickers hardness after rotational plastic working can secure HV 230 or more, in addition to the effects of the invention according to claims 1 to 3, rotational plastic working is possible. While securing hardness,
High drum hardness as a product can be secured.

According to a fifth aspect of the present invention, in the shaft member with a drum in which a drum having internal teeth is fixed to a shaft member having an oil hole, spline teeth, or the like, the shaft member and the drum are made of a single material. And the shaft member is
The carburized hardened layer is formed on the surface, and the drum is a member with internal teeth formed by rotational plastic processing.Therefore, low production cost, high product quality, and prevention of tooth inclination,
It is possible to provide a shaft member with a drum integrally having a drum that achieves both high precision and high strength while preventing the axial center deviation of the drum.

In the invention according to claim 6, claim 5
In the shaft member with a drum described above, the shaft member is a shaft provided in the automatic transmission for transmitting power, the drum rotates integrally with the shaft, and a clutch plate is slidably fitted to the internal teeth. Since the drum is a drum, in addition to the effects of the invention described in claim 5, the clutch plate can move smoothly along the internal teeth when the clutch is engaged and released, preventing clutch dragging and plate uneven wear, and durability durability of the clutch. Can be improved.

[Brief description of the drawings]

FIG. 1 is a process chart illustrating a method for manufacturing a shaft member with a drum according to the first embodiment.

FIG. 2 is a work temperature characteristic diagram in a heat annealing step of the method for manufacturing a shaft member with a drum according to the first embodiment.

FIG. 3 is a cross-sectional view showing a shaft member with a drum according to the first embodiment.

FIG. 4 is a cross-sectional view showing a power transmission mechanism of an automatic transmission to which the shaft member with a drum manufactured by the manufacturing method according to the first embodiment is applied.

FIG. 5 is a 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 internal teeth 6 Case hardening layer 7 Mold 8 Forming roller 10 Input shaft (shaft member with drum)

Claims (6)

[Claims] 1. Using a single material having a shaft member and a disk-shaped drum portion, oil holes and spline teeth are machined on the shaft member, and the drum portion is stretched by forging to form a preform of rotational plastic working. Machining process, carburizing and quenching process to form a carburized hardened layer on the entire surface of the machined material, and rotary annealing by heating and annealing only the drum part of the quenched material that is subjected to rotational plastic processing Heat-annealing process to make the hardness possible, and setting the mold on the heat-annealed drum section, and moving the forming roller relative to the drum section while keeping the pressing of the forming roller against the drum section to make the internal teeth And a cold rotational plastic working step of forming a drum having: a method of manufacturing a shaft member with a drum. 2. The method for manufacturing a shaft member with a drum according to claim 1, wherein the heat annealing step is a step of performing heat annealing in a vacuum or in an inert gas such as nitrogen. Manufacturing method of a shaft member with a shaft 3. The method for manufacturing a shaft member with a drum according to claim 1, wherein the heating and annealing step includes increasing a workpiece temperature to a set annealing temperature level, and uniformizing a hardness distribution of the annealed portion by heating and holding. A method of maintaining a workpiece temperature raised to a time that can be reduced to a maximum value. 4. The method for manufacturing a shaft member with a drum according to claim 1, wherein the Vickers hardness after annealing is HV1.
A method for producing a shaft member with a drum, characterized in that the annealing conditions are such that the Vickers hardness after rotation plastic working is HV230 or more. 5. A shaft member with a drum in which a drum having internal teeth is fixed to a shaft member having an oil hole, spline teeth, and the like, wherein the shaft member and the drum are integrally formed of a single material. A shaft member with a drum, wherein the shaft member is a member having a carburized hardened layer formed on a surface thereof, and the drum is a member having internal teeth formed by rotational plastic working. 6. The shaft member with a drum according to claim 5, wherein the shaft member is a shaft provided in an automatic transmission for transmitting power, the drum rotates integrally with the shaft, and a clutch plate is provided on the internal teeth. Is a clutch drum fitted slidably.