JPS61235030A - Production of cylindrical member - Google Patents

Abstract

PURPOSE:To increase the accuracy in the out-of-roundness and wall thickness, etc. by applying the pressure in radial direction according to the plastic deformation on a cylindrical member. CONSTITUTION:The device to give the necessary dimensional accuracy to cylindrical member 1 is composed of the die 2 having a bore 3 the punch 4 providing a core 5 on its tip, knockout punch 6 and base stand 7. The cylindrical member 1 is press-fitted by the force P into the bore 3 of the die 2 in the state of fitting it to the core 5 of the punch 4. In this case the outer diameter D2 of the core 5 is formed in advance larger than the inner diameter of the cylindrical member 1 prior to the work. By the press-fitting of the core 5, therefore, the force in the diameter spreading direction is given to the cylindrical member 1. Due to the bore 3 of the die 2 being produced with extremely high accuracy the cylindrical member 1 is strongly press-connected by the outer peripheral face of the core 5 and the inner peripheral face of the bore 3 and the out-of- roundness and wall thickness accuracy are increased.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a method for manufacturing a cylindrical member, and particularly to a method for manufacturing a cylindrical member that can significantly improve the accuracy of the cylindrical member.

[Conventional technology]

Conventionally, as a cylindrical member, a rectangular plate-shaped material was curved and both ends of the material were butted together. So-called butt-type cylindrical members, or so-called clinch-type cylindrical members in which a rectangular plate-shaped material is curved and recesses and protrusions formed at both ends thereof are engaged with each other are known. ing.

As a means for improving the accuracy of roundness, wall thickness, etc. of this type of cylindrical member, a shaft core disposed within one cylindrical member and a holder disposed on the outer surface side of the cylindrical member are used. A so-called sizing method in which the cylindrical member is compressed in the radial direction is known as Japanese Patent Publication No. 55-11415.

[Problem that the invention seeks to solve]

The so-called sizing method known as the above-mentioned Japanese Patent Publication No. 55-11415 etc. is considered when it is desired to have higher accuracy on the inner circumference of a cylindrical member, or conversely, when it is desired to have higher precision on the outer circumference of a cylindrical member. It has not been. Therefore, since the design is based on the side that requires higher precision, the mold and the device have become large and complex.

Furthermore, when molding a cylindrical member made of bimetallic material with copper, aluminum, and resin bonded to a steel backing plate, the side to which the copper, aluminum, and resin are bonded is better than the side of the backing steel plate. It is easy to cause soft plastic deformation, but it is not possible to select which of the inner and outer circumferences should be more plastically deformed.
A great deal of force was required.

[Means for solving problems]

The present invention was made in order to solve such conventional problems, and the shaft core is inserted into a cylindrical member, and this cylindrical member is placed in the bore of a holder to apply a radial pressing force. A method for manufacturing a cylindrical member, wherein the inner diameter of the bore and the outer diameter of the cylindrical member, or the outer diameter of the shaft core and the inner diameter of the cylindrical member are set to be the same, and the gap between the bore and the shaft core is set to the same value as the cylindrical member. By making it smaller than the wall thickness of the member.

By applying a radial pressing force that causes plastic deformation to this cylindrical member, it is attempted to obtain a cylindrical member with improved accuracy in terms of roundness, wall thickness, etc.

[Effect]

In the present invention, one of the inner diameter of the bore and the outer diameter of the cylindrical member, and the outer diameter of the shaft core and the inner diameter of the cylindrical member are set to the same size, and the gap between the bore and the shaft core is set to be smaller than the wall thickness of the cylindrical member. Since an important component is to apply a pressing force that causes plastic deformation in the radial direction to this cylindrical member, the accuracy of the cylindrical member is improved, and the following effects are also achieved.

In other words, if the inner diameter of the bore and the outer diameter of the cylindrical member are set to be the same and the gap between the bore and the shaft core is smaller than the wall thickness of the cylindrical member, the cylindrical member will undergo plastic deformation in the radial direction. Since more pressing force is applied, the inner circumferential side of the cylindrical member is more plastically deformed.On the other hand, if the outer diameter of the shaft core and the inner diameter of the cylindrical member are set to be the same, the bore and the shaft core are When the gap is made smaller than the wall thickness of the cylindrical member, more pressing force is applied to the cylindrical member that causes plastic deformation in the radial direction, so the outer circumferential side of the cylindrical member is more likely to be plastically deformed. be. Utilizing this effect, the former method can be selected for cylindrical parts that require higher accuracy on the inner periphery, and the latter method can be selected for cylindrical members that require higher accuracy on the outer periphery. effective. Furthermore, the back metal plate is made of copper and aluminum.

When molding a cylindrical member made of bimetallic material to which resin is bonded, copper-based, aluminum-based,
Since the side to which the resin is bonded is softer and easier to plastically deform, it is desirable to use a method in which the softer side is more plastically deformed so that a cylindrical member with higher precision can be obtained with less force. Is there a side on the inner circumference that is more likely to undergo plastic deformation?

There is also the effect that the method can be selected depending on whether it is on the outer circumference side.

〔Example〕

Hereinafter, one embodiment of the present invention will be explained using a butt type cylindrical member as an example.

First, Fig. 1 shows a butt-type cylindrical member (1), which is made by bending a rectangular plate-shaped material and attaching both ends to each other, as is conventionally known. It is formed by butting together. and a second cylindrical member (1
) is provided with the required dimensional accuracy by the apparatus shown in FIG. 2, the configuration of which is as follows. That is, as is clear from FIG. 2, this device includes a die (2) provided with a bore (3) into which a cylindrical member (1) is inserted, and a die (2) that is inserted into the cylindrical member (1) at its tip. A punch (4) with a protruding core (5) is pushed into the bore (3) with the force shown in the figure (P).
), a knockout punch (6) facing this punch (4), and a base (7) that supports the die (2).
), and the bore (
The diameter (Dl) of 3) is the outer diameter (Dl) of the cylindrical member (1) before processing.
D, ), and the core (5) of the punch (4)
) is the inner diameter (D2) of the cylindrical member (1) before processing.
4) It is formed with a larger diameter. That is, dice (2)
The gap between the core (5) and the core (5) of the punch (4) is set smaller than the wall thickness of the cylindrical member (1) before processing.
5) Attach the cylindrical member (1) to the die (2)
This cylindrical member (1) can be press-fitted into the bore (3) of the
A radial force will be applied to the The bore (3) and core (5) are molded with high precision to match the planned finishing dimensions of the inner and outer diameters of one cylindrical member.

Therefore, to explain the manufacturing method of the cylindrical member (1) using the above-mentioned apparatus, in manufacturing, prior to the above-mentioned precision imparting processing, a rectangular plate-shaped material is first curved and both ends of the material are butted against each other to form the cylindrical member (1). 1) Mold.

Next, this cylindrical member (1) is inserted into the core (
5), put this cylindrical member (1) into a die (
2) into the bore (3) with force (P) as shown. In this case, since the diameter (D2) of the core (5) is larger than the inner diameter (D4) of the cylindrical member (1) before processing, the cylindrical member ( 1) is subjected to a force in the direction of diameter expansion. Therefore, the cylindrical member (1
) is manufactured in advance with high precision and is strongly pressed against the inner circumferential surface of the bore (3) and the outer circumferential surface of the core (5), giving it exceptionally high roundness and wall thickness accuracy. becomes.

This is clear from the following experimental results.

In other words, one applicant claims that the diameter (Dl) of the bore (3) is 49
．． Diameter (D2) of 65φ die (2) and core (5)
Using a punch (4) with a diameter of 44.88 φm, a machining experiment was conducted on a cylindrical member (1) with an outer diameter (D3) of 49° and 65 φm before machining.

This results in a roundness of 10 to 50 μm and a wall thickness variation of 2
It was possible to obtain values of 0 to 50 μm and straightness of 10 to 50 μm.

Note that the relationship between the diameter (Oo) of the bore (3) and the outer diameter (D,) of the cylindrical member before processing does not necessarily have to be exactly the same, but may vary in roundness and wall thickness.

It has also been confirmed that the desired effect can be achieved if the straightness is set within the standard range.

Normally, the standard for this type of cylindrical member is a roundness of 150 iz.
m or less, and the variation in wall thickness is less than 150 μm, so
From the above experimental results, it can be confirmed that sufficiently good precision can be obtained by the method of the present invention.

In addition, in the embodiments and processing experiments described above, the diameter (D2) of the core (5) of the punch (4) was made larger than the inner diameter (04) of the cylindrical member (1) before processing to form a cylindrical shape. Although the explanation has been given on a case in which a force is applied in the direction of diameter expansion to the member (1), the diameter (D2) of the core (5) and the inner diameter (D4) of the cylindrical member (1) before processing are the same, Katsu dice (
The diameter (D) of the bore (3) in 2) is smaller than the outer diameter (D, ) of the cylindrical member (1) before processing.
) can also provide a highly accurate cylindrical member (1) by applying a force in the diameter-reducing direction.

As explained above, in the first embodiment of the present invention,
Curving a rectangular plate-shaped material to form a butt-type cylindrical member, then inserting a shaft core into this cylindrical member and placing this cylindrical member in a bore of a holder,
By setting the inner diameter of the bore and the outer diameter of the cylindrical member, or the outer diameter of the shaft core and the inner diameter of the cylindrical member to be the same, and making the gap between the bore and the shaft core smaller than the wall thickness of the cylindrical member. Since a radial pressing force accompanied by plastic deformation is applied to the cylindrical member, the roundness and wall thickness accuracy of the cylindrical member can be significantly improved.

Therefore, it is clear that when this cylindrical member is used as a bearing, abnormal heat generation and seizure can be effectively eliminated.

Next, another embodiment of the present invention will be described using a clinch type cylindrical member as an example.

FIG. 3 shows a clinch type cylindrical member (11), which has a concave portion (11a) and a convex portion (llb) at both ends, as is conventionally known. The provided substantially rectangular plate-shaped material is curved, and the recess (lla) and the projection (llb) are engaged with each other to connect and connect the abutting portions. This cylindrical member (11) is given the required dimensional accuracy by the device shown in FIG. It has basically the same structure as the device used.

That is, this device is as shown in FIG.

A die (12) is provided with a bore (13) into which the cylindrical member (11) is inserted, and a core (15) protruding from its tip to be inserted into the cylindrical member (11) is inserted into the bore (13). Illustration (P
The punch (14) that is pushed in with the force of l) and this punch (
14), and a base (17) that supports the die (12).

With these configurations, it is possible to apply compressive force in the axial direction to the cylindrical member (11), similarly to the embodiment shown in FIG. 3 above. However, unlike the device used for the butt-type cylindrical member (1) described above, this device applies a force in the diametrical direction to the cylindrical member (11) instead of applying a force in the radial expanding direction. It is unique that it is like this.

That is, the diameter (D) of the bore (13) of the die (12)
) is formed to have a smaller diameter than the outer diameter (OZ 3) of the cylindrical member (11) before processing, while the core (
The diameter (D1□) of 15) is the same as the inner diameter (D, ,) of the cylindrical member (ii) before processing6.Therefore, the cylindrical member (11) has a die (12) and a punch. (1
4), a force in the direction of diameter reduction is applied.

Note that the reason why we applied a force in the diametrical direction to the cylindrical member (11) instead of applying a force in the radial expanding direction is because when applying a radially expanding force to the clinch type cylindrical member (11), This is because an undesirable separation phenomenon occurs at the clinch portion, that is, the engagement portion between the recess (lla) and the convex portion (llb).

Next, to explain the manufacturing method of this clinch type cylindrical member (11), like the above-mentioned butt type, when manufacturing, first, a rectangular plate-shaped material is curved, and the recesses at both ends are formed. (lla) and convex part (ll
b) are engaged with each other to form a cylindrical member (1) as shown in FIG.
1) Mold.

Next, the core (15) of the punch (14) is inserted into this cylindrical member (11), and in this state, the cylindrical member (11)
Using the force shown (P□), press the die (
12), the diameter (Di,) of the bore (13) will be the outer diameter (D) of the cylindrical member (11) before processing.
3) Since it is formed with a smaller diameter, the above-mentioned bore (13)
Press-fitting operation.

As a result, a compressive force is applied to the cylindrical member (11) in the direction of diameter reduction. In this way, the cylindrical member (11) is compressed between the bore (13) and the core (15), which have high dimensional accuracy, and can be given extremely excellent roundness and wall thickness accuracy.

Note that at this time, there is an effect that the outer peripheral side of the cylindrical member is more plastically deformed.

As explained above, according to the method of the second embodiment of the present invention, the rectangular plate-shaped material is curved and the concave portions and convex portions formed at both ends of the material are engaged with each other to form a clinch type material. Molding a cylindrical member, then inserting a shaft core into the cylindrical member, placing the cylindrical member within a bore of a holder, and setting the inner diameter of the bore to be smaller than the outer diameter of the cylindrical member. By making the gap between this bore and the shaft core smaller than the wall thickness of the cylindrical member, a compressive force in the direction of diameter reduction is applied, thereby preventing a separation phenomenon at the clinch portion of the cylindrical member. I'm not used to causing it,
It is possible to significantly improve roundness and wall thickness accuracy.

(Effects of the Invention) The present invention sets the inner diameter of the bore and the outer diameter of the cylindrical member, or the outer diameter of the shaft core and the inner diameter of the cylindrical member to be the same, and the gap between the bore and the shaft core of the cylindrical member. By making it smaller than the wall thickness, a radial pressing force that causes plastic deformation is applied to the cylindrical member, thereby making it possible to obtain a cylindrical member with improved accuracy in roundness, wall thickness, etc. Furthermore,
This has the effect of making it possible to select which of the inner and outer circumferences of the cylindrical member should be more plastically deformed.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing a butt type cylindrical member, FIG. 2 is a sectional view showing an example of a device for processing this cylindrical member, and FIG. 3 is a perspective view showing a clinch type cylindrical member. FIG. 4 is a sectional view showing an example of an apparatus for processing this cylindrical member.

Claims (1)

[Claims] A cylindrical member is formed by curving a rectangular plate-shaped material, and then an axial core is inserted into the cylindrical member and the cylindrical member is placed in the bore of the holder, and the cylindrical member is pressed in the radial direction. In the method for manufacturing a cylindrical member that applies pressure, the inner diameter of the bore and the outer diameter of the cylindrical member, or the outer diameter of the shaft core and the inner diameter of the cylindrical member are set to be the same, and the gap between the bore and the shaft core is set as described above. A method for manufacturing a cylindrical member, characterized in that desired accuracy is imparted to the cylindrical member by applying a radial pressing force that causes plastic deformation to the cylindrical member by making the thickness smaller than the wall thickness of the cylindrical member.