JPH02247029A - Plastic combining method - Google Patents

Abstract

PURPOSE:To restrain deformation of cylindrical inner face by pressurized- forming ring-like recessed parts on side face of the cylinder and plastic- combining a round plate having hole corresponding to the outer circumference thereof with the cylinder. CONSTITUTION:The cylinder 1 is inserted into the round plate 2 having hole part and the neighborhood of the inner circumference of the round plate 2 having hole is pressurized with a lower die 3 and an upper die 4 having ring-like projections, and the side face of the cylinder 1 is pressurized with a lower die 5 and an upper die 6 having ring-like projections to form the ring-like recessed parts. Material of the forming part is plastic-deformed and the hole diameter in the round plate 2 is shrunk and brought into contact with the outer face of the cylinder 1 to come to the combining force between the cylinder 1 and the round plate 2, and the cylinder 1 is made to deform the diameter thereof toward shrinking direction. Force for forming the ring-like recessed parts on side faces of the cylinder 1 is made to deform the inner face of the cylinder 1 to barrel-shape and by offsetting both, the inner face accuracy is improved.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for plastically joining a perforated disk and a cylinder, and more particularly to a method for plastically joining a cylinder inner surface with good accuracy.

[Conventional technology]

As a method for joining members to be joined made of two metal materials, there is a plastic joining method as described in Japanese Patent Publication No. 57-46931. Although this method has high bonding strength and high working efficiency, there is a problem in that the inner surface of the cylinder is deformed when the perforated disk and the cylinder are bonded. Next, the problem will be explained in detail.

FIG. 5 is a diagram showing a method of joining the cylinder 1 and the perforated disc 2 using the above-mentioned plastic joining method. Cylinder 1 with a hole in the disc 2
is inserted, and a pair of lower molds A5. having a ring-shaped protrusion are inserted. The upper mold A4 pressurizes the vicinity of the inner circumference of the perforated disk 1 from above and below to form four ring-shaped parts. The material of the molded part is plastically deformed, and part of the material flows in a direction that reduces the hole diameter of the disk, comes into contact with the outer surface of the cylinder, and generates a force that reduces the cylinder. This force becomes the binding force between the cylinder 1 and the perforated disk 2. Due to the bonding force, the cylinder is deformed in the direction of decreasing diameter,
The inner surface of the cylinder also deforms.

Next, the results of a specific study on the deformed state of the inner surface of the cylinder will be explained. Cylinder 1 has an outer diameter of 160u and an inner diameter of 1100mm.
Tl, Height 64U1 Material 545C, - universal disk 2
is outer diameter 500wIL, inner diameter 160ffffi, plate thickness 12
111jE.

The material is 5PHC. Then, a case where a ring-shaped recess with a width of 2 mm and a depth of 0.55 m>x was formed near the inner periphery of the perforated disk 2 was analyzed using the finite element method. Figure 6 shows the analysis results of the deformed state of the inner surface. The overall tendency is for the diameter to shrink (40 μm in terms of radius shrinkage)
, the shrinkage is particularly large at the center in the height direction, and smaller at both ends (deformed into an hourglass shape), and the difference therebetween is 12 μm. When press-fitting a bearing into the inner surface of a cylinder, the tolerance S is approximately 5=12.5 μm in radius. The cause of the error is the error δ1 due to the deformation of the hourglass shape due to the above-mentioned plastic bonding.
In addition, there is an error δ2 when manufacturing (cutting) the cylinder of material. The relationship between tolerance and error is S≧\1δ12+δ22. There are various combinations of the distribution ratio of δ1 and δ2, but if they are distributed evenly, δ1. δ2≦8.8 μm. Therefore, the above drum-shaped deformation δ1 = 12 μm
In this case, a good product cannot be obtained, and it is necessary to reduce δ1.

In addition, high precision can also be achieved by performing finishing processing such as cutting after plastic bonding, or by cutting the inner surface of the cylindrical material into a barrel shape in anticipation of deformation of the bond, but this increases the number of processing steps. There is a problem in that the increase is particularly significant in the case of large fish.

[Problem to be solved by the invention]

The above-mentioned conventional technology does not take into account the accuracy of the inner surface of the cylindrical hole, and the inner surface of the hole deforms into an hourglass shape, causing problems when inserting the bearing.

The purpose of the present invention is to eliminate the problems of the prior art described above,
This invention relates to a durable joining method with good hole inner surface accuracy.

[Failure to solve the problem]

The above object is achieved by forming a ring-shaped recess in the side surface of the cylinder.

[Effect]

When a ring-shaped recess is formed on the side surface of a cylinder, the inner surface of the cylinder is deformed into a barrel shape. As a result, the hourglass-shaped deformation of the cylindrical inner surface caused by the plastic bonding is offset, and the same inner surface accuracy is achieved.

〔Example〕

An embodiment of the present invention will be explained below with reference to FIG. The cylinder 1 is inserted into the perforated disc 2, and the lower mold A6 and upper mold A4 form a ring-shaped protrusion near the inner periphery of the perforated disc 2. Lower mold B5 and upper mold B
6 to form a ring-shaped recess.

As a specific processing example, the cylinder 1 has an outer diameter of 160u, an inner diameter of 100mm, a height of 64myn, and a material of S 45G. - A disc with a blade hole 2 has an outer diameter of 50011JIL, an inner diameter of 100mm, a plate thickness of 12mm, and a material of SP'. It is HC. The shape of the ring-shaped recess formed near the inner periphery of the perforated disk 2 has a width b+=21nfL and a depth hl-α, as the cross section is shown in FIG.
The shape of the four ring-shaped parts formed on the side surface of the cylinder 1 is 65U, and the width b2 = 2, as the cross section is shown in Fig. 3.
magazine, depth bz=0.1U.

Next, the results of analyzing this effect using the finite element method will be explained. FIG. 4 shows the analysis results of the inner surface shape of the cylinder 1. The deformation depth is 7 μm, which is the value of the conventional technology (12
μm) has been significantly improved, and the target value is 88 μm.
It is within

Note that a general-purpose press can be used to apply processing force to the mold. However, since the depth h2 of the recess formed into the cylinder 1 and the depth hl of the recess formed into the perforated disk are different, it is desirable to perform the formation by multiple presses. Of course, molding may be performed using separate presses as two-step molding.

Furthermore, the optimum values for the width b2, depth h2 and the position of the recess formed into the cylinder 1 are the shape and material of the cylinder 1 and the perforated disk 2, as well as the width b+ and depth hl of the recess formed into the perforated disk. and changes depending on its location. The optimum value can be easily determined by the above-mentioned finite element analysis or experiment taking these conditions into consideration.

In the embodiments described above, the shapes of the four parts molded into the cylinder 1 are square, but other shapes such as a 0-shape may also be used.

Further, in order to strengthen the plastic bonding force, knurling or the like may be provided on the outer peripheral surface of the cylinder 1, but the same effect can be obtained in this case as well.

〔Effect of the invention〕

According to the present invention, deformation of the inner surface of the cylinder that occurs when the cylinder and the perforated disc are plastically bonded can be suppressed, so that the bearing can be press-fitted smoothly without finishing.

[Brief explanation of drawings]

Fig. 1 is a longitudinal sectional view of an embodiment of the present invention, Figs. 2 to 4 are partially enlarged views of Fig. 1, Fig. 5 is a longitudinal sectional view showing the prior art, and Fig. 6 is a partially enlarged view. It is a diagram. Explanation of symbols

Claims (1)

[Claims] 1. A method in which a cylinder made of a metal material and a disk having a hole corresponding to the outer periphery of the cylinder are pressurized near the inner periphery of the disk from the thickness direction of the disk to plastically bond the two members. ,
A plastic bonding method characterized by pressurizing and forming a ring-shaped recess on the side surface of a cylinder.