JP4080092B2 - Drive shaft manufacturing method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention is a method of manufacturing a drive shaft comprising yokes forming part of a universal joint at both ends, and having an intermediate sliding portion by spline fitting of a male shaft member and a female shaft member, Male shaft member,
a) a hollow shaft member having one end connected to the yoke of the universal joint and having an inner diameter larger than the outer diameter of the female shaft member;
b) Manufactures a drive shaft constituted by a male spline member having a sliding spline portion slidably fitted into the spline hole of the female shaft member and a fixing portion fixed to the inner surface of the hollow shaft member. It is about how to do.
[0002]
[Prior art]
It may be desirable to allow either the male shaft member or the female shaft member to contract in the axial direction when an axial stress is applied to the drive shaft that contracts beyond a predetermined expansion / contraction stroke. For this reason, it is proposed that the male shaft member or the female shaft member is constituted by at least two parts, and these two parts are connected by a shear (shear) pin that is broken when a predetermined load is applied. . Further, there is a configuration in which a male shaft member or a female shaft member is connected to a tube that contracts in the axial direction when a stress exceeding a predetermined load is applied in the axial direction. Furthermore, there has also been proposed a method in which two parts are connected to each other by a snap ring, key connection, spline fitting between metals, or an adhesive.
[0003]
[Problems to be solved by the invention]
However, in such a shear pin, there are only two portions where the connecting support portions of the two members face each other in the diametrical direction, and the load control differs from the intended one due to material fatigue of the pin during long-term use. There is a fault that becomes a thing. That is, the initial load limit is lowered. Moreover, it is difficult to control the load using a deformed tube. That is, there is a drawback that it is difficult to determine the load limit of how much the contraction is caused in the initial stage.
[0004]
Accordingly, an object of the present invention is to obtain a method for manufacturing a drive shaft of the above-described type that facilitates load control of contraction when a stress greater than a predetermined load is applied.
[0005]
[Means for Solving the Problems]
In order to achieve this object, the manufacturing method of the drive shaft of the present invention includes:
Resin coating is applied to one of the inner surface of the hollow shaft member and the fixed portion of the male spline member, and the other is formed with continuous grooves or dents dispersed with each other,
After the male spline member is inserted into the inner surface of the hollow shaft member, the fixing portion is heated to melt the resin coating, and a part of the resin flows into the continuous grooves or the recesses dispersed from each other. The male spline member is fixed to the hollow shaft member by re-molding to be cured.
The sliding spline portion of the male spline member fixed to the hollow shaft member is slidably fitted into the spline hole of the female shaft member.
[0006]
In this configuration of the present invention, when axial displacement and axial load outside the normal operating range are applied to the drive shaft, the female shaft member exceeds the sliding spline portion of the male spline member and the end surface of the female shaft member is male. The male spline member is pressed in the axial direction by engaging with the end face of the fixed portion of the spline member. This axial load is caused by the elastic restoring force of the resin coating between the inner surface of the hollow shaft member and the fixed part of the male spline member, and the frictional engagement holding force by the resin biting into the continuous grooves or the dents dispersed from each other, and When the limit of the shear force is exceeded, the male spline member moves in the axial direction with respect to the hollow shaft member, and the male shaft member contracts as a whole, that is, the entire drive shaft contracts greatly.
[0007]
According to the present invention, the load control is performed by distributing the thickness of the resin coating on one of the inner surface of the hollow shaft member and the fixed portion of the male spline member and the continuous grooves into which a part flows due to heat melting of the resin to be coated or mutually distributed. It can be managed by the total area of the depression. As this heating method, for example, induction heating such as high frequency or component welding heat is used.
[0008]
In a preferred embodiment of the present invention, a fixing spline portion is formed on the inner surface of the hollow shaft member, and the fixing portion of the male spline member is fitted to the fixing spline portion. Form. According to this configuration, relative rotation between the hollow shaft member and the male spline member can be reliably prevented.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
Next, preferred embodiments of the present invention will be described with reference to the drawings.
[0010]
As shown in FIG. 1, a drive shaft 1 according to the present invention includes a male shaft member 4 connected to a yoke 3 (see FIG. 1B) of one universal joint 2, and a spline fitting with the male shaft member 4 And a female shaft member 8 connected to the yoke 7 of the other universal joint 6.
[0011]
According to the present invention, the male shaft member 4 includes a hollow tube 9 having one end connected to the yoke 3 of the universal joint 2, a hollow shaft member 10 connected to the other end of the hollow tube, and the hollow The shaft member 10 and the male spline member 11 that is spline-fitted are configured. However, the hollow shaft member 10 can be directly connected to the universal joint yoke 3 without the hollow tube 9 interposed.
[0012]
The hollow shaft member 10 is provided with a dust seal 12 that slidably contacts the outer surface of the female shaft member 8. The inner surface of the hollow shaft member 10 is larger than the outer diameter of the female shaft member 8, and preferably, a fixing spline-shaped portion 13 is formed as a spline hole having a smaller inner diameter that is larger than the outer diameter of the female shaft member 8. Further, in the illustrated embodiment, an annular groove 15 is formed on the inner surface 14 of the hollow shaft member 10 on the hollow tube 9 side adjacent to the fixing spline-shaped portion 13.
[0013]
The male spline member 11 is provided with a sliding spline portion 17 coated with a resin so as to be slidably fitted into the spline hole 16 of the female shaft member 8. Further, in a region opposite to the sliding spline portion 17, a fixing portion that is fixed to the inner surface of the hollow shaft member 10, preferably a fixing spline portion 18 that is fitted to the fixing spline-shaped portion 13 of the hollow shaft member. Is provided.
[0014]
According to the present invention, the resin coating 22 is applied to one of the inner surface 14 or the fixing spline-shaped portion 13 of the hollow shaft member 10 and the fixing portion or the fixing spline portion 18 of the male spline member 11, and the other Consecutive grooves or recesses 19 distributed with one another, in the embodiment shown, spiral grooves 19 are formed. Instead of the spiral groove 19, a plurality of annular grooves separated from each other or dents dispersed with each other may be formed. In the preferred embodiment shown in the figure, a resin coating 22 is applied to the inner surface 14 of the hollow shaft member 10 or the fixing spline-shaped portion 13, and a helical groove 19 is formed in the fixing portion or fixing spline portion 18 of the male spline member 11. To do.
[0015]
As shown in an enlarged view in FIG. 2, the spiral groove 19 is formed on the inner surface 14 of the hollow shaft member 10 or the fixed portion 18 of the male spline member 11 by cutting (see FIG. 2A) or rolled. It is formed by manufacturing (see FIG. 2B). The cross-sectional shape of the groove can be any shape such as an arc shape, a square shape, or a tapered shape. When the groove is formed by rolling, it is preferable to form a slight protrusion on the large spline diameter side along the edge of the groove as shown in FIG.
[0016]
After the resin coating 22 is applied on one side and the hollow shaft member 10 and the male spline member 11 formed with continuous grooves or mutually dispersed depressions 19 are fitted to each other, the fixing portion of the male spline member 11 or The periphery of the fixing spline portion 18 is heated by induction heating such as high frequency or welding heat during component welding. By this heating, the resin coating is melted, and a portion of the resin facing the continuous grooves or the dispersed recesses 19 flows into the continuous grooves or the dispersed recesses 19. After the resin is hardened, the fixing by the frictional engagement holding force between the hollow shaft member 10 and the male spline member 11 is ensured by re-molding the hardened resin in the continuous grooves or the recesses 19 dispersed with each other.
[0017]
In order to reliably prevent the hollow shaft member 10 and the male spline member 11 from being unintentionally released during normal use, an annular formed on the hollow shaft member 10 as in the preferred embodiment shown in the drawings is preferable. The peripheral edge of the stopper plate 20 is fitted into the groove 15 to prevent the normal male spline member 11 from entering the hollow tube 9.
[0018]
When the fixing spline part 18 is provided on the male spline member 11, the female shaft member 8 is engaged with the end surface of the male spline member 11 when the sliding spline part 17 contracts more than the set value. The phases of the sliding spline portion 17 of the male spline member that is slidably fitted into the spline hole 16 of the member 8 and the fixing spline portion 18 that is press-fitted into the fixing spline shape portion 13 of the hollow shaft member 10 are set. Preferably, a phase difference of ½ of the pitch of the spline peaks or valleys is provided.
[0019]
Further, in order to ensure that the female shaft member 8 is engaged with the end surface of the male spline member 11 regardless of whether or not the fixing spline is formed, the fixing portion 18 of the male spline member is radially arranged in the female shaft member. It is preferable to provide an annular guide groove 21 that is larger than the outer diameter of 8 and in which the end surface of the fixing portion 18 accommodates the tip end portion of the female shaft member 8.
[0020]
Generally, the axial displacement of the drive shaft during normal use in automobiles, agricultural machinery vehicles, industrial machinery vehicles, and construction machinery vehicles is 0 to 200 mm, and the axial load is 0 to 1000 kg. More axial displacement and load are applied to the drive shaft, and the inner surface 14 of the hollow shaft member 10 or the fixing spline-shaped portion 13 that protrudes into the continuous groove of the fixing portion or fixing spline portion 18 or the recesses 19 dispersed with each other. The male spline member 11 moves toward the inside of the hollow tube 9 in the axial direction with respect to the hollow shaft member 10 when the limit of the holding force of the friction engagement with a part of the resin of the resin coating 22 is exceeded. . Further, when the stopper plate 20 is provided, the male spline member 11 slides relative to the hollow shaft member 10 due to deformation or breakage of the stopper plate 20 or detachment from the annular groove 15 of the stopper plate 20. The male shaft member 4 contracts as a whole, and therefore the entire drive shaft 1 contracts greatly.
[0021]
【The invention's effect】
Thus, according to the present invention, the load control of the contraction exceeding the limit of the normal sliding stroke of the drive shaft is applied to one of the fixing spline forming portion of the hollow shaft member and the fixing spline portion of the male spline member. Part of the resin of the resin coating provided on the other of the fixing spline forming part of the hollow shaft member and the fixing spline part of the male spline member enters the continuous groove or the dents distributed to each other and hardens. It can be managed by the frictional holding force and the shear force between the reshaped resin coating and the continuous grooves or the dents distributed to each other. That is, the total amount of the resin that bites into the continuous grooves or the mutually dispersed depressions, and accordingly, the opening area of the continuous grooves or the dispersed depressions can be finely managed. Further, when the stopper plate is provided, it can be managed by the deformation strength or breaking strength of the stopper plate or the frictional engagement holding force with the annular groove of the stopper plate.
[0022]
Furthermore, according to the present invention, the resin can be easily re-molded by flowing it into continuous grooves or hollows dispersed with each other using induction heating such as high frequency or welding heat at the time of component welding. Fixing between the shaft member and the male spline member can be performed easily and reliably.
[Brief description of the drawings]
FIG. 1 shows a drive shaft according to the present invention, in which (a) is a side view showing a partial cross section of a main portion of the drive shaft, and (b) is a partial cross section of a universal joint on a side connected to a male shaft member. (C) is an enlarged vertical sectional view of a part of (a).
FIG. 2 is an enlarged partial sectional view of a spline fitting portion of a hollow shaft member and a male spline member.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Drive shaft 2, 6 Universal joint 3, 7 Yoke 4 Male shaft member 5 Shaft part 8 Female shaft member 9 Hollow tube
10 Hollow shaft member
11 Male spline member
12 Dust seal
13 Spline shape part for fixing
14 Inside
15 annular groove
16 Spline hole
17 Sliding spline section
18 Fixed spline section
19 Spiral grooves (continuous grooves or dents distributed to each other)
20 Stopper plate
21 Annular guide groove
22 Resin coating

Claims (2)

A manufacturing method of a drive shaft comprising yokes forming part of a universal joint at both end portions, and having an intermediate sliding portion by spline fitting of a male shaft member and a female shaft member, the male shaft member comprising: ,
a) a hollow shaft member having one end connected to the yoke of the universal joint and having an inner diameter larger than the outer diameter of the female shaft member;
b) Manufacture of a drive shaft constituted by a male spline member having a sliding spline portion slidably fitted into the spline hole of the female shaft member and a fixing portion fixed to the inner surface of the hollow shaft member. In the method
Resin coating is applied to one of the inner surface of the hollow shaft member and the fixed portion of the male spline member, and the other is formed with continuous grooves or dents dispersed with each other,
After the male spline member is inserted into the inner surface of the hollow shaft member, the fixing portion is heated to melt the resin coating, and a part of the resin flows into the continuous grooves or the recesses dispersed from each other. The male spline member is fixed to the hollow shaft member by re-molding to be cured.
A drive shaft manufacturing method comprising: sliding a spline portion of a male spline member fixed to the hollow shaft member to be slidably fitted into a spline hole of the female shaft member. The drive shaft according to claim 1, wherein a fixing spline-shaped portion is formed on an inner surface of the hollow shaft member, and the fixing portion of the male spline member is formed as a fixing spline portion that is fitted to the fixing spline-shaped portion. Production method.

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