JPS60149728A - Heat treatment of flywheel - Google Patents

Abstract

PURPOSE:To obtain a flywheel free from generation of hardening strain and quenching crack by hardening the tooth part of a cast iron ring gear part disposed on the outside circumference in a flywheel body part by a laser, etc. then subjecting said part to high-temp. tempering treatment. CONSTITUTION:While a mirror 6 is in the position (a), a laser beam hardens the right face shown in the figure of the tooth face in a ring gear tooth part 5a through routes A, B. When the mirror 6 is moved to the position (b), the laser beam is reflected by the mirror 6 and is passed through routes A, C to harden the left side shown in the figure of the tooth part 5b. The ring gear 5 is then rotated right or left by as much as one tooth and the above-described operation is repeated. The above-mentioned operation is repeated for the tooth parts over the entire circumference of the ring gear part by which the tooth faces in the tooth parts over the entire circumference of the ring gear part are hardened. The integral cast iron ring gear 5 is thereafter subjected to a high-temp. tempering treatment. The cast ion ring gear is used after low-temp. tempering treatment.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a flywheel heat treatment method.

For more information, see flywheel for Enodine.

It is possible to improve the impact resistance of the ring gear teeth on the outer periphery without causing quenching distortion or quench cracking of the flywheel.This method involves heat treatment of the flywheel.

[Prior art]

Conventionally, as shown in Fig. 1, a flywheel for an engine has a flyhorn main body 1 made of ordinary cast iron (JIS standard F (25)) and a steel ring gear R1<2 disposed around its outer circumference. are made into two parts a'' and made into an integral structure by fitting means such as shrink fitting.

In order to ensure the abrasion resistance and high fatigue strength of the mountain parts, the linogya part 2 is constructed according to J'IS standard 548.
J-co induction hardening using C material or.

Carburizing and quenching using JIS standard 515C material is usually carried out.

FIGS. 2 and 3 show conventional induction-hardened and carburized flywheels, respectively.

This is the hardened pattern of the ring gear teeth.

In induction hardened products, the quenching depth is relatively deep as shown in FIG. 2, and quenching strain and pjaj distortion are likely to occur.

In addition, for carburized and quenched products, as shown in Figure 3.

The quenching depth is 1. Although it is shallow (less than mm), it has the disadvantage of increasing distortion of the entire flywheel because it is necessary to exhaust heat from the entire flywheel.

In addition, in this conventional split f7+\ molded flywheel, (+) the flywheel main body part 1 and the renoguya part 2 are
After machining with two presses for each, it is necessary to fit with one piece such as shrink fit and perform two machining processes, so multiple pins, i, jj
The manufacturing cost would be extremely high.

(■ Increase the quenching depth of the tooth bottom of the line gear part 2 to a deeper 7
11 G. Ring cap part 1 due to residual stress during shrink fitting
(μ) is likely to occur, and for this reason, the depth of the tooth root needs to be relatively shallow, and as a result of this, the strength of the ring gear cannot be maximized.

(2) Therefore, in such a split-structure flywheel, there is a possibility that the engine gear part will be damaged during high-speed rotation, so the engine rotational speed is restricted.

There were problems such as.

Therefore, the flywheel main body part and the line gear part were integrally cast. The use of a flywheel 3 as shown in Fig. 4 is being considered, but in this case, it is necessary to provide wear resistance and high fatigue strength to the linoge gear part.
Induction hardening is commonly practiced. However, when the regular U-frequency hardening treatment is applied to the ridge portion of the flywheel 3 made of integral cast iron, the entire ridge portion of the ridge gear 1 is likely to be hardened as shown in FIG.

And, the ring gear tooth part of the single-piece cast iron small fly eel is induction hardened using the conventional method.

When the surface is hardened by high 1fl wave quenching, the hardness of the quench-hardened ridge portion becomes about Hv600±20, the quench-hardened dentinal portion becomes more sensitive to notches, and the fatigue strength of the dente becomes lower.

Therefore, for the induction hardened product of the flywheel 3 made of monolithic casting, the hardness of the width part of the linen gear can be adjusted to a range of Hv300 to Hv 500 by heating the lined part of the lined gear or by controlling the cooling after high frequency heating. By adjusting the link gear 141 part resistance +Ii 4US
Although it is possible to improve the bending strength and fatigue strength, such heat treatment has the disadvantage that sufficient impact resistance cannot be ensured because the base is quenched and hardened.

1. :, In the heat treatment method described in l, the quench hardening depth is deep, so 1 minute -f! I h'^ In the molded flywheel,
There is a drawback that cracking occurs when the parts are shrink-fitted.

Furthermore, if the heat treatment method described above is applied to a flywheel made of integrally cast J2, it will be 7.1□E during induction hardening.
: There is a drawback that it is easy to cause errors.

[Purpose of the invention]

The present invention has a flywheel main body and a flywheel arranged on its outer periphery to be divided into nine parts or integrally formed.
, '11's linoge gear part is machined on a flywheel made of steel or cast iron without heat treatment [After that, the linoge gear part is locally thinly annealed using high-density energy such as laser hardening or electron beam hardening. Low-temperature tempering is applied to Jingo Steel Rinogeya.

By subjecting cast iron linoguya to high-temperature tempering, there is less occurrence of hardening claws and cracking of the flywheel.For flywheels with a two-piece structure, cracking and distortion occur during fitting due to shrink fitting. As a result, it can improve the mountain attack resistance of 31 types. The purpose of the present invention is to provide a method for heat treatment of flywheels.

[Structure of the invention]

According to the present invention, a flywheel main body and a ring gear i4+ are arranged around the outer periphery of the flywheel body.
A method for heat treating a flywheel in which the wheel is divided into one piece or integrally formed, and the outer circumferential liner part is made of steel or cast iron.

After hardening the peaks of the linoge gear part using high-density energy such as a laser or an electron beam, the flywheel is hardened by low-temperature tempering for 1 hour linoge gears and high-temperature tempering for cast iron linoge gears. It is characterized by improving the impact resistance of the linoge gear teeth without causing distortion or quench cracking. This is accomplished by the fly-4-el heat treatment method.

〔Example〕

Hereinafter, one embodiment of the present invention will be described in detail based on the accompanying drawings.

FIG. 5 shows an example in which the linage tooth portions 5a and sb of the flywheel 5 are hardened by laser hardening as an example of di, l.

In the figure, 4 is a laser generator, 5 is a rinogya, 5a
, '5b is the ring gear crest, and 6 is the mirror.

When mirror 6 is in position A, the two beams are A and B.
O) Quench and harden the right side of the tooth section of the linage gear tooth section 5a in the drawing through the route.

Next, when the mirror 6 is moved to the position, the laser beam is reflected by the mirror 6 and passes through the paths A and C to quench and harden the left side of the ring gear part 5b in the figure.

Next, the ring gear 5 is rotated by one rotation to the right or left, and the above-mentioned operation is repeated.

By repeating the above operation on the ridges around the entire circumference of the ring gear part, the meat 1ffi of the ridges around the entire circumference of the ring gear part can be quenched and hardened.

First, the mirror 6 is fixed at position A, and the ring gear 5 is sequentially rotated one by one to harden the right tooth flank in the figure of the teeth around the entire circumference. Even if the left screen in the diagram of the tooth portion around the entire circumference of the ring gear part is quench-hardened in a state in which it is moved and fixed, it is possible to similarly quench-harden the m part around the entire circumference of the ring gear part. After this, the integral cast iron ring is subjected to high-temperature tempering, and the steel ring is subjected to low-temperature tempering before use.

FIG. 6 shows a second embodiment in which the linage gear teeth are quenched and hardened using an electron beam.

7 is an electronic heat gun, and 8 is a deflection coil.

The deflection coil 8 is similar to the mirror 6 in FIG.
It plays the role of switching the electron beam E7i-F to G direction.

The quench hardening method is similar to laser hardening, and the m-beam E is first switched using the polarizing coil 8, and the liner gear 5 is sequentially rotated to perform quench hardening. In this case, the one-piece cast iron nogeya is subjected to high-temperature tempering treatment, and the copper renogeya is subjected to low-temperature tempering treatment.

FIG. 7 shows the quench-hardening pattern of the peak portion of β1L which has been hardened by the above-mentioned Ray → Noheem or 'F4 child heel quench hardening method.

As mentioned above, according to the method of the present invention, since the auxiliary hardening is performed by local heating, there is little quenching distortion, and in a flywheel with a one-piece structure, i%lI deviation does not occur during shrink fitting. do not have.

In addition, since it is an auxiliary hardening, as shown in Fig. 8, 1,
Compared to the hardened product of the conventional method, the re-impact resistance of the linogya crest is significantly lower.

・Furthermore, the occurrence of quenching cracks during quenching can be significantly reduced compared to the A-frequency heating and water jet quenching of conventional method 1.

[Function and effect of the invention]

As is clear from the above, according to the flywheel heat treatment method according to the present invention, the flywheel body portion and the liner cap portion are arranged on the outer periphery of the flywheel body portion.

After machining in a non-heat-treated state, the ring gear teeth are attached to a flywheel that is either split or integrally formed and whose outer ring gear is made of steel or cast iron.

After one local thin-burning process using high-strength heat treatment such as laser hardening and rM beam hardening, low-temperature tempering should be applied to steel linoges, and heat-tempering treatment should be applied to integrally cast and manufactured linoges. This reduces the occurrence of quenching distortion and quenching cracks in the flywheel.Furthermore, in the split structure flywheel, there is no cracking or distortion caused by shrinkage fitting, etc., and the rain impact resistance of the lino gear I and In parts is improved. It has the advantage of being able to improve

[Brief explanation of drawings]

Figure 1 shows a one-disassembly structure wall flywheel, i:C1m
tfii diagram. FIG. 2 is a diagram showing the cylindrical frequency quenching hardening pattern of the rear part of the linog. Fig. 3 is a diagram showing the d charcoal hardening (C) hill of the Rinoguya mountain area. Fig. 4 is a longitudinal sectional view of monolithic cast iron fly oil. Fig. 5 is an overview showing the laser hardening method. Fig. 61.A is a +' Ill heam hardening method schematic diagram 1:, 4r 7 l is 14.1 part laser hardening or ``1lLf-heam hardening,
fJ'l D4 L/A section showing a treated hardened pattern. Figure 8 compares the impact strength of Φj of Rinogekya θz1 part L
/ Tagera 7. 1. Fly oil main body, 2. Renogeka section. 3-1 Honbo, Lbu, Kema flywheel. 4 Laser generator, 5 Rinoguya. 5a, 5b Lingekyaerabe, 6 ・Mirror. 7 Electron beam generator, 8- (knitting coil. A, Low Mirror position. A, B, C... Ray → F beam path. E, F, G Electron beam path output 1fg'j Person I-Yota Jidosha Co., Ltd.Figure 1Figure 2Figure 3Figure 5Figure 6Figure 7Figure 8

Claims (1)

[Scope of Claims] 1. A heat treatment method for a flywheel in which a flywheel main body part and a ring gear part are disposed on the outer periphery of the flywheel body and are formed separately or integrally, and one part of the ring gear on the outer periphery is made of cast iron. Laser 2.u
After hardening with areal density energy such as a child beam, high-temperature tempering treatment will cause quenching distortion and quenching cracks in the flywheel, and it is difficult to improve the impact resistance of the ring gear teeth. Features. 2 Heat treatment method for flypoil.