JPS5812093B2 - Joint structure of two metal parts - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a joint structure obtained by inserting a third joining member into a gap between two joined members and applying cold pressure to plastically flow the joint member. The present invention relates to a coupling structure suitable for use in firmly fixing shafts, discs, and cylindrical members to each other.

A bonding structure is known in which a third bonding object is inserted between two objects to be bonded.

That is, this method involves inserting a sleeve made of non-ferrous metal into the gap between the shaft and rotor joint, and crimping the sleeve using upper and lower molds.

If the shaft is provided with a groove, the sleeve will bite into it when tightening, providing a fixing force.

However, with this method, the sleeve does not fully dig into the groove, resulting in a gap of δ.

This is because the deformation resistance of the sleeve is uniform, so the internal stress σ1 of the end of the sleeve increases before the stress σ3 of the middle part of the sleeve increases to the extent that sufficient plastic deformation occurs due to the tightening load applied to the sleeve. This is because deformation occurs due to this, and therefore an increase in σ3 is suppressed.

(This point will be discussed in more detail later.) Furthermore, there is also the effect of friction loss between the joining member and the joined member during processing.

Therefore, sufficient bonding force between the shaft and the loaf, especially a high bonding force that resists rotational torque, cannot be obtained.

Furthermore, the method shown in FIG. 1 is also known as a structure in which a third bonding object is inserted between two objects to be bonded.

That is, the two rod-shaped members 6 and 7 are each provided with a groove having an uneven portion, and a connecting rod 8 having an uneven portion corresponding to the uneven portion is inserted into both grooves to connect them.

This method has the disadvantage that the connecting rod 8 must be manufactured in advance in accordance with the shape of the uneven portions of the rod-like members 6 and 7, resulting in low productivity and difficulty in obtaining a large bonding force.

In addition, as a structure that directly connects two objects to be connected,
The method shown in FIGS. 2 and 3 is also known.

That is, this is a method in which the hollow disk 9 is directly joined to the stepped portion of the shaft 1.

The shaft 1 is provided with a groove 1a.

The method is as shown in Fig. 3, by using upper and lower molds 3 and 4 having convex portions 3a and 4a, respectively, to press the end of the disc 9 and to bite the joint part of the disc into the groove 1a of the shaft. , is a method of obtaining bonding force.

However, in this method, as shown in FIG. 4, a portion of the disk does not completely dig into the groove 1a, resulting in a gap δ.

This is because the deformation resistance in each part of the disc is equal, so even if the end of the disc is pressed with a mold and an internal stress σ3 is generated, this stress deforms the outer part of the disc that is less constrained. This is because it is not possible to generate stress large enough to cause sufficient plastic deformation locally only in the groove portion.

It is an object of the present invention to provide a joining structure for joining two members to be joined, which allows freedom in selecting materials for the two members to be joined, and which allows a mechanically strong joint to be easily obtained. It is in.

The features of the present invention are as follows.

That is, the mutually opposing joint surfaces of the two members to be joined each have a recess.

These joint surfaces face each other with a constant gap.

On the other hand, a joining member made of a material having a lower deformation resistance than the members to be joined and having a predetermined mechanical strength and having a height equal to or slightly lower than the height of the void is inserted into the void.

The coupling force of the double-wave coupling member is obtained by the shearing force and tension force of the coupling member.

The present invention will be explained in detail below with reference to the drawings.

FIGS. 5 to 8 are diagrams explaining the basic principle of the present invention.

First, in FIG. 5, the first coupled member 110 and the second
Both members 120 to be joined are metal disks, and there is a width T between the joining surfaces 111 and 121 of both members.

, a ring-shaped cavity 140 with a height H8 is interposed.

Additionally, grooves 112 and 122 are provided in the direction perpendicular to the surface, respectively.

113 and 123 are joint end faces.

On the other hand, 130 is a joining member made of a metal that is more easily plastically deformed than the joined members 110 and 120, that is, has less deformation resistance, and has a width T1.

The height Hl is approximately equal to or slightly smaller than H8, and the height H1 is equal to or slightly higher than H8.

Even when Hl is higher than Ho, the difference ΔH is preferably kept as small as possible, for example, 0.2 to 0.3 at a time.

The reason for this will be explained later.

In addition to the rectangular cross section shown in the figure, the connecting member may have a simple shape such as a round, elliptical, or polygonal cross section.

It is not necessary to take the shape of a cavity to cause plastic deformation after insertion.

In the bonding process, first, as shown in FIG.
Insert into 40.

Next, as shown in FIG. 7, the whole is placed on a mold 40, and the cavity width T is set.

Pressure part 3 of mold 30 having tip surface 31 with smaller width
2, the connecting member 130 is pressurized and the groove 112 is formed by plastic deformation.
, 122, the coupling member 130 is introduced into the coupling member 130.

The insertion process shown in FIG. 6 may also be performed using the mold 30.

In the state shown in FIG.
It is surrounded by a gap 140 except for the upper and lower end portions corresponding to , and the height difference ΔH is extremely small.

Therefore, it can be said that in the state immediately before pressurization, the entire joining member is surrounded by the void and the mold.

Therefore, as shown in FIG. 7, the coupling member hardly escapes to the outside of the gap when pressurized.

As shown in FIG. 8, the pressurizing protrusion side surface 33 of the mold 30 is inclined by θ with respect to the direction perpendicular to the distal end surface 31 (insertion direction).

θ is preferably about 6° to 15°.

This is because if θ is small, it becomes difficult for the mold 30 to come out after joining.

In addition, if θ is too large, the joining member will tend to flow out of the cavity in the opposite direction to the insertion direction of the mold, and the insertion depth will not be deep enough to generate large internal stress in the joining member. Therefore, it becomes difficult to obtain a large bonding force.

As shown in FIG. 8, the mold pressurizing part 32 is
It is desirable that the distance S between this and the upper ends of the grooves 112, 122 of the member to be coupled be as small as possible, in other words, it is desirable that the distal end surface 31 be inserted as deeply as possible as close to the grooves 112, 122 as possible.

This reduces friction loss associated with plastic flow,
The coupling member can be fully inserted into the groove.

When the member 120 to be joined has a hole 125 in the center, positioning during pressurization can be easily performed by providing a guide 33 in the mold 30, as shown in FIG. can.

Further, the depth of the four pressurizing parts 131 is such that the grooves 112 and 122 are sufficiently filled with the coupling member 130 and the coupling member 13
The dimensions are sufficient to allow the necessary tension to remain inside the 0.

FIG. 10 is a diagram showing a state in which the connection is completed.

In the figure, there is a tension force P inside the coupling member 130.

acts to firmly expand the grooves 112, bonding surfaces 111, grooves 122, and bonding surfaces 121 of the first and second objects 110 and 120 to be bonded.

Here, in order to maintain the configuration as shown in the figure, it is necessary that the material of the first object 110 and the second object 120 be harder and have greater rigidity than the material of the joining member 130. becomes.

This is because while the bonded object 130 is pressurized by the mold 30 and plastically flows, the first bonded object 110 and the second bonded object 120 do not deform (although there is some distortion). , it must be sufficiently solid.

In other words, the joining object 130 is the first joining object 1
10 and the material has lower deformation resistance than the second object 120 to be bonded.

For example, when the first and second objects to be joined are steel 4 materials, the objects to be joined are made of aluminum, brass, copper, mild steel, or the like.

Although the bonded object itself may be made of a non-metallic material, it is required to have a certain mechanical strength against shearing, compression, bending, etc.

Needless to say, its size varies depending on the usage conditions of the members to be joined.

Next, the relationship between the height H6 of the joining member 130 and the height Hl of the cavity of the joined member will be described.

In order for the coupling member 130 to sufficiently flow into the gap 140 between the members to be coupled, the volume of the coupling member only needs to be equal to the volume of the gap.

However, as shown in FIG. 11, if a joining member 130 with a relatively large height difference ΔH is used for joining, the ends of the joining member will be deformed, as shown in FIG. 12.

Therefore, as shown in FIG. 13, even if the volume of the coupling member is greater than the volume of the gap, δ1. A void portion δ2 remains.

In other words, it produces the same result as the previously known bonding method described above.

This is due to the following reason.

In FIG. 13, when a ring-shaped coupling member 130 is compressed in the axial direction by the molds 30 and 40, an internal stress of σ1 in the axial direction, σ2 in the circumferential direction, and σ3 in the radial direction is generated in the coupling member. arise.

(Figures 14 and 15). On the other hand, there is a relationship where the deformation resistance of this coupling member is Kf.

During pressurization, no restraining force acts in the radial direction near both ends of the coupling member 130, so when σ is at its maximum, σ2 is at its minimum.

Therefore, the stress force (THE-8CA
), the following relationship holds true.

When equation (1) is substituted into equation (2), stress sufficient to plastically deform the joining member in the radial direction, that is, into the groove of the joined member, is not generated.

On the other hand, according to the method of the present invention as shown in FIG.
40 and is restrained by the mold convex portion, and when substituted into Equation (2) 7, it becomes as follows, and stress of 1 or more is generated in the deformation resistance.

The coupling member therefore flows completely into the groove.

In order to restrain the joining member during pressurization in this manner, it is sufficient that the height H7 of the joining member is approximately equal to or less than the height of the cavity.

However, if the height of the connecting member becomes too low, it becomes necessary to increase the insertion stroke of the mold convex part to allow sufficient flow into the groove, but there is a limit to the stroke because θ cannot be made too small. .

Therefore, the volume of the coupling member is set to be slightly smaller than the volume of the cavity, and the cavity width T o .

It is necessary to determine the height Hl in consideration of the mold inclination angle θ and the like.

FIG. 16 is a comparison diagram of the bonding strength of the bonding structure of the present invention and other structures.

In the figure, A is the method of FIG.
〜The method explained in FIG. 13, B is the structure of FIG. 17B,
That is, the case is based on the conventionally known structure explained in FIGS. 2 to 4, and C is based on the structure shown in FIG. 17C, that is, the coupling structure of the present invention.

The bonding material is mild steel, and the diameters (a1 to a4) are 17th
The dimensions are shown in Figures C and D (unit: TrrIn).

Reference numerals 170 and 171 are holes for measuring rotating torque.

In method A, the rotational torque is 26 kg/m1B, whereas in the method, gK9/m, according to structure C of the present invention,
A high torque of 47 kg/m was obtained.

The reason why such a high rotational torque is obtained is that, as mentioned above, the gap between the members to be joined is completely filled with the joining member, producing a large drag force.

On the other hand, the axial pulling force is as shown in FIG.

Here, the shearing area A is πd 2 Hs (rran2) when expressed using d2°Hs shown in FIG.

The extraction force changes depending on the mechanical strength of the bonding material (mild steel, copper) and shearing area.

In order to further increase the rotational torque, as shown in FIGS. 19 and 20, axial unevenness portions 113 and 123 may be provided intermittently on the circumference of the joint end surfaces of the joined members 110 and 120. good.

(FIG. 20 shows the AA cross section in FIG. 19.

) FIG. 21 shows the magnitude of rotational torque obtained for the shape (unit: wIL) shown in FIGS. 19 and 20.

The horizontal axis is the groove width of the uneven part (a x height 2h) x the number of grooves (n)
It is necessary.

- It can be seen that the rotating torque increases by increasing the area of the uneven portion.

Next, FIG. 22 shows a perspective view, partially in section, of another embodiment of the present invention.

In this embodiment, unlike FIG. 10, pressure is applied from both sides of the coupling member 130.

Compared to FIG. 10, a more stable tension force can be obtained.

FIG. 23 shows a partially sectional perspective view of another embodiment of the invention.

In this embodiment, each of the first coupled member 110 and the second coupled member 120 has two grooves, that is, a recess 112.
A.

112B, and four parts 122A, 122B.

It also has two pressurizing recesses 131 and 132.

Such a configuration is effective when the members to be coupled are thick.

Note that even if the deformation resistance of the members to be joined is greater than the deformation resistance of the joining member, if the wall thickness is thin, the joining member will be deformed during joining, and the joining member will not be able to flow into the gap effectively.

Therefore, the members to be joined must have a certain degree of rigidity.

However, there is also a need to join thin-walled members.

In such a case, as shown in FIG. 24, a holding part 41 may be provided in a part of the mold 40 on the side where the rigidity is insufficient to compensate for the insufficient rigidity.

The same applies when both members to be joined have insufficient rigidity.

As is clear from the embodiments described above, the present invention is applicable to the case where the gap is maintained in a constant state by the two members to be joined.

For example, two concentric disks, a shaft and a disk.

On the other hand, in cases where the gap is not maintained in a fixed shape by the two members to be joined, such as two parallel plates, even if the joining member is inserted between the two members, the connection will not occur. You can't get power.

In other words, the insertion of the joining member must cause a tension force to be exerted between the joining member and the member to be joined.

The present invention as described above has the following effects.

First, since the required tension force P can be applied to the bonding surfaces 111 and 121 and the recesses 112 and 122, a mechanically stable bonding force can be obtained.

Furthermore, since the recesses 112 and 122 are filled with the bonded object 130, the pull-out force Q becomes the product of the shear strength and shear area of the material of the bonded object 130, and thus becomes an extremely large value.

Further, a first object to be coupled 110 and a second object to be coupled 1
20 has greater deformation resistance (harder) than the bonded object 130
Because it is a material, the first object 1 and the second object 2 are not distorted by pressurization or plastic flow.
High accuracy is maintained.

This means that, in the case of this joining method, the objects to be joined can be assembled in a form that has undergone the dimensional accuracy and surface treatment of the final product in advance, and can be said to be an advantageous assembly method.

In addition, the first object to be connected 110 and the second object to be connected 120
can select the necessary materials for the product configuration.

The combined object 130 is the above-mentioned connected object 11.
This is possible by selecting a material with a smaller deformation resistance than 0.120.

Furthermore, the bonding material may have a simple shape, and since it is joined by cold working, the production process is simple, the productivity is high, and small-scale equipment such as a hydraulic press for pressurization is sufficient.

In terms of quality, the tension force P can be secured and stabilized with a length that manages the pressurization pressure.

The embodiments described above relate to the structure of the coupling portion which is the basis of the present invention.

Examples of application to products are shown below, along with their effects.

FIG. 25 shows a partial half cross section of an electromagnetic clutch employing the present invention.

The electromagnetic clutch 200 is connected to a compressor body 20 for a car cooler.
It is attached to 0A.

The specific configuration is shown below.

A boss 211 is fixed to a compressor shaft 210 supported by a bearing 201 with a nut 213, and a disk-shaped disk 220 is formed via a spring 212.

The disk 220 adopts the present invention, and as shown in FIG. 26, it includes a concentric circular disk 221 made of a magnetic material (steel material), a circular disk 222, and a coupling member 223 made of a non-magnetic material (brass). The details are integrated in a joint structure equivalent to that shown in FIG.

The rotor 230 is connected to the compressor main body 200 via the bearing 202.
It is attached to A.

According to the present invention, the rotor 230 includes three concentric disks made of magnetic material (steel material), a rotor plate 231, a rotor plate 232, a rotor plate 235, a coupling member 233 made of a non-magnetic material (brass), and a coupling member. 234, and the details are integrated with a connecting structure equivalent to that shown in FIG.

Further, a rotor boss 236 and a pulley 237 are integrally welded to the rotor plate 235 and rotor plate 231, respectively.

A belt is engaged with the pulley 237, and the compressor 200A is driven by the automobile engine.

The electromagnetic coil 203 is composed of a yoke and a coil.
It is directly fixed to the compressor main body 200A.

Next, the operation will be explained.

When the electromagnetic clutch 200 is not energized, the pulley 237
Only the rotor 230 driven by the engine rotates, and the disk 220 and boss 2 that are separated through the gap rotate.
11. The shaft 210 is stationary.

When the electromagnetic coil 203 is energized, the magnetic flux φ flows as shown by the broken line.

That is, the yoke of the electromagnetic coil 203 → the pulley 237 → the rotor plate 231 → the gap → the disk 221 → the gap → the rotor plate 232 → the gap → the disk 222 → the gap → the rotor plate 235 → the rotor boss 236.

This magnetic flux φ causes the disk 220 to be attracted to the rotor 230, electromagnetically coupled thereto, and rotated.

Therefore, the shaft 2
10 rotate in synchronization.

Here, each of the coupling members 223, 233, and 234 has sufficient mechanical strength to withstand rotational torque, and at the same time, as mentioned above, is made of a non-magnetic material that does not pass magnetic flux, so magnetic flux leakage occurs. can be minimized.

FIG. 27 shows the rotor 24 in a conventional electromagnetic clutch.
FIG. 2 is a perspective view showing a disk portion of No.

In the figure, the disc part is punched out from a single steel plate using a press, and includes a rotor plate 241, a rotor plate 242, a rotor plate 245, a connecting part 246 having four radial widths B, and a radial connecting part 246 having a width B. It is formed of four connecting portions 247 and grooves 243° and 244 each having a width C.

Although not shown in the drawings, a conventional disc may also be used for rotor 2.
This is a configuration equivalent to 40.

In this conventional rotor 240, the magnetic flux φ also flows into the ineffective magnetic paths of the connecting portions 246 and 247, so that the effective magnetic flux is reduced, and the electromagnetic clutch is inevitably large.

As shown in FIG. 26, by employing the coupling method using a coupling member made of non-magnetic material according to the present invention, the rotor 240 is free from ineffective magnetic paths such as the coupling portions 246 and 247 of the conventional structure, and can be used as a car cooler. An electromagnetic clutch with an outer diameter smaller by approximately 20% was obtained.

Figure 28 shows compressor swash plate 2 of a swash plate compressor for car coolers.
50 is a partially cross-sectional perspective view illustrating a method of coupling 50 and shaft 260 according to the present invention.

The compressor swash plate 250 for a car cooler converts the rotation of the shaft 260 into the reciprocating motion of a piston that engages with the swash plate through a ball or the like, and is made of cast iron, which is a material with little elongation. , which have traditionally been joined by shrink fitting.

However, there are limits to vibration and impact force, and problems such as loosening may occur under severe conditions.

In the present invention, a recess 25 is provided on the inner surface of the compressor swash plate 250.
1, a corresponding recess 261 is formed on the outer periphery of the compressor shaft 260 made of special steel, a bonded object 270 made of a mild steel material with low deformation resistance is inserted and pressurized, and a corresponding recess 261 is formed on the outer periphery of the compressor shaft 260 made of special steel. They are bonded by plastic flow.

Therefore, the compressor swash plate 250 has sufficient stable mechanical strength against rotation, thrust load, and impact, and is easy to process.

FIG. 29 shows another embodiment of the present invention, and is a partially sectional perspective view of an object to be bonded.

As in the case of disk 220 in FIG.
The member to be joined 221 and the second member to be joined 222 are often processed from the same thick plate material by a method such as punching.

In such a case, the first coupled member 221 and the second coupled member 222 are not separated, but the connecting member 283 is sheared and moved as shown in FIG. I'll keep it.

Next, in the connected state, the recess 285 and the recess 286 are simultaneously turned and formed.

In this state, the steps shown in FIGS. 6 and 7 are added to join and integrate, and then the connecting portion 284 is separated and the connecting member 2
83 is removed.

The advantages of the present invention include that machining of the recesses is completed in one step, and that the number of parts is small and productivity is high.

FIG. 30 shows the present invention as shown in FIG. 25.
This shows an example of application to the production of 237.

Conventionally, the pulley piece 23 is attached to the boss part of the pulley piece 237A.
The inner ends of 7B were welded together.

In this method, thermal deformation occurs after welding, so post-processing of the structural surface was required.

When employing the joining method of the present invention, each pulley piece 2
Grooves 239° 240 are formed in the corresponding parts of 37A and 237B, and then pressed with molds 241, 242° 243, and mold 24
4, the coupling member 245 can be inserted into the groove and plastically coupled.

According to the bonding structure of the present invention, the bonding strength is stable.

Furthermore, since there is no thermal deformation due to welding, the pulley piece 237
As A and 237B, pre-plated parts can be assembled as they are, so they can be integrated in the parts assembly line, resulting in high productivity.

In addition to the above-mentioned application examples, the present invention also applies to cylinders and shafts,
Can be applied to a wide range of connections such as shafts and plates, and can be used to connect disks, cylinders, shafts, cylinders, flat plates, rods, etc.

[Brief explanation of the drawing]

1, 2 and 3 are longitudinal cross-sectional views showing examples of conventionally known bonding methods, and FIG. 4 is an explanatory diagram of the bonding state of the method shown in FIGS. 2 and 3. FIG. 5 and subsequent figures are diagrams explaining the present invention in detail. FIG. 5 is a partial cross-sectional perspective view showing the main external appearance of the members to be joined and the joining member before joining, and FIG. 6 is the diagram showing the joining member. Fig. 7 is a perspective view showing the state in which the members to be joined are inserted into the cavity, Fig. 7 is a perspective view showing the state in which the joining member is pressurized by the mold, and Fig. 8 is a cross section of the main part showing the conditions of pressurization. FIG. 9 is a diagram showing a modified example of the mold. FIG. 10 is a perspective view showing the state after the connection is completed. 11 to 13 are diagrams for explaining the conditions required of the coupling member. 14 and 15 are diagrams for explaining the state of stress during pressurization. FIG. 16 is a diagram illustrating the results of a comparison of coupling forces between the method of the present invention and other methods with respect to rotational torque, and FIG. 1T is an explanatory diagram of each method in FIG. 16. FIG. 18 is a diagram showing the magnitude of the axial pulling force when the shearing area is changed for each material of the coupling member.・Figure 19 is a diagram showing a modification of the present invention that increases rotational torque, and Figure 20 is a cross section taken along line A-A in Figure 19, and shows the groove width, height, and rotation of the dimensions shown in both figures. The results of determining the torque relationship are shown in FIG. FIG. 22 is a diagram showing an example in which the coupling member is pressurized from above and below, and FIG. 23 is a diagram showing a modified example of the shape of the cavity. FIG. 24 is a diagram showing an example of reinforcing with a mold when the rigidity of the outer joined member is insufficient. FIG. 25 is a longitudinal cross-sectional view of a main part of an electromagnetic clutch to which the coupling method of the present invention is applied, FIG. 26 is a perspective view showing the external appearance of the clutch plate shown in FIG. 25, and FIG. 27 is a diagram shown in FIG. 26. FIG. 2 is a perspective view showing the appearance of a conventional clutch plate corresponding to the clutch plate of FIG. FIG. 28 is a longitudinal cross-sectional view of essential parts of a swash plate compressor to which the coupling method of the present invention is applied. FIG. 29 is a perspective view of essential parts showing a modification of the coupling method of the present invention. FIG. 30 is a longitudinal cross-sectional view of a main part of a pulley to which the coupling method of the present invention is applied. 110... Member to be coupled, 112... Groove, 120... Member to be coupled, 122...
Groove, 130...Connection member.

Claims (1)

[Scope of Claims] 1. The first member to be joined has a cylindrical inner peripheral surface of the joint and the end face of the joint, the second member to be joined has a cylindrical outer peripheral surface of the joint and the end face of the joint, In the case where a coupling member is interposed between the two coupling surfaces, the two cylindrical coupling surfaces face each other with a certain gap over a range of the entire axial length or a predetermined depth from the end face of the coupling part, and the two cylindrical coupling surfaces face each other with a certain gap between them. A joint having a concave portion continuous over the entire circumference of the intermediate portion of the surface joint surface at a position, the concave portion and the metal body in the gap being made of a material having lower deformation resistance than the material of the double-wave joint member and having a predetermined mechanical strength. A structure for joining two metal members, characterized in that the members are filled and the joining force of the two-wave joining member is obtained by the shearing force and tension force of the joining member. 2 The first member to be joined is a disc or cylinder having a hole in the center, the second member to be joined is a disc or shaft having an outer diameter slightly smaller than the diameter of the hole, and the second member is a disc or a shaft having an outer diameter slightly smaller than the diameter of the hole; A structure for joining two metal members according to claim 1, characterized in that a groove is provided along the circumferential direction in the portion. 3. The first member to be coupled is a disk having a hole in the center,
Claim 1, characterized in that the second member to be coupled is a disk or a shaft having an outer diameter that fits into the hole, and a gap portion serving as a coupling portion is formed in a part of the fitting surface. 1
Connection structure of two metal members as described in the section. 4 The first member to be coupled is a disk having a hole in the center,
Claim 1, characterized in that the second member to be joined is a cylinder having an outer diameter that fits into the hole, and a cavity serving as a joining part is formed in a part of the fitting surface. A joint structure of two metal parts.