JPS60208422A - Coil for induction-hardening gear - Google Patents

Abstract

PURPOSE:To increase the toughness of the roots of the teeth of a gear and to improve the fatigue strength by fixing triangular projections which mesh with the gear and coolant nozzles on the inside of a circular high-frequency heating coil so as to harden the gear along the outline at a stroke. CONSTITUTION:A circular coil 11 for induction-hardening a gear has triangular projections 12 which mesh with the gear on the inside and coolant nozzles 15 each at the bottom 13 between projections 12. A gear placed in the coil 11 is induction-heated with the coil 11, and a coolant is spouted parallel to the surfaces 14 of the projections 12 toward the bottoms 3 of the teeth of the gear. The gear is hardened along the outline by said heating and quenching.

Description

DETAILED DESCRIPTION OF THE INVENTION Regarding the 11h frequency quenched NiDOIL of the present invention 8.1,
The second correction is 'I, the whole of the small mountain - the ring'/l (i
+'L person, lt-, 11jI frequency power that every digit is C
Regarding the L-insertion coil.

・In general, induction hardening is performed to improve wear resistance and fatigue resistance.

In general, induction hardening involves applying a high-frequency current to induce eddy currents on the surface of an object to be heated, such as a float, and heating the surface of the object with the Joule heat of the eddy current. There are four types of cooling quenching. When heating ζi'1Ijlt for such induction hardening, for small gears, the gear is induction-heated while rotating around its axis in an annular high-frequency induction heating coil whose inner surface is a circumferential surface, and then the coil is heated. Coolant is injected from the coolant injection holes η and j provided on the inner circumferential surface, and the threads are rapidly cooled and hardened.For gears with large thread widths, the coil is moved in the face width direction. After induction heating the floats, they are immediately rapidly cooled and hardened.
There is ζ.

However, according to such a conventional coil, when the entire small gear is induction hardened, the distance between the inner circumferential surface of the coil and the tip and tooth bottom is large, so the peak 1j is usually As a result of adding F and h to the ′i element and ′ζ uniform heating,
As shown in Fig. 1, the entire crest of the gear, including the tip 1, C↑1, face 2, and tooth bottom 3, is hardened and contour hardened, that is, a hardened layer of uniform depth is formed along the tooth profile. Not only can it not be formed, but it also has gears? In order to achieve a JI Hl surface shape (j), during cooling by jetting a cold Jilt agent from the inner peripheral surface of the coil, the inside of the coil is not uniformly cooled, and the hardness also decreases.
The cracking caused by 11 hours of quenching was large.

7 (Already in 11 Proceedings of the Japan Society of Mechanical Engineers Part 1 No. 27 Color No. 182 (Showa 36-1-), a small float was set at an angle of about 500 degrees (Choj1 medium or high frequency 1-1 + ifi JJI).
After heating, the ring is formed by high-frequency heating, oil cooling and quenching. L in the mountains
The hardness of the tip of the C tooth on the L base is low, and the hardness is even when the C refill is applied. In addition, after adding +:':IIΔ1 waves to the float, the inner peripheral surface was formed into a corrugated surface.
IT; Place the mountain 11 (inside i, inject the cold JJI agent from the corrugated surface in the direction of its normal horn, and harden the mountain !Ij ?c)
) method is also used in 1, and is not hardened.

The present invention has been made in order to solve the problems mentioned in 111''4.
Naris 1 and 1! ', r14 to form hardening jI・'i' → Rugoto's
:, 'Provide a frequency hardened coil (j (for the purpose of 4
Ru.

In the induction hardening process of the float according to the present invention, after the float is placed inside and heated by induction heating, a coolant is injected onto the float to rapidly cool it, and the gear is heated to ring 91 (annular high frequency induction heating for hardening). The coil has triangular protrusions on its inner circumferential surface to engage with the tooth grooves in the gear, and coolant is sprayed at the bottom between the protrusions toward the bottom of the gear tooth and parallel to the protrusion surface. There are cooling injection holes that open to allow
It is characterized by being

FIGS. 2 to 4 show an embodiment of an induction hardened coil for a gear according to the present invention.

This coil 11 is hardened on its inner peripheral surface! The number of triangular protrusions 12 that can fit into the tooth grooves of one wheel is the same as the number of teeth (i
L, spray coolant on the bottom 13 between the protrusions toward the lij bottom 3 of the tooth i1i and parallel to the protrusion surface 14! J.L.
A cooling injection hole 15 that opens L1 is provided in the cooling injection hole 15. Although the bottom part between the protrusions is not limited, during the induction heating J5 of the float, it is necessary to prevent overheating of the destination and to ensure that the coolant is uniformly distributed in the width direction of the float.
It is formed flat, and this flat bottom smells like a cold jail.
Punishment 11i "1 TIHL wrote 1 / Cold on the J side) Sprayed the 41 agent 'JJ L7i:! 1L) opened 11 Shi (Iron's trick 7. On the other side, Ta Ij, ~j song was cold. JJI 1NI
l ``Doubles with 1' (Tori IIG is installed +1 1'
+ :11. 'g 2. .

This, 1)・'1 list IC le 31, the float's +1':+
I, 'il wave mining's h method (first-order and I method).

In Fig. 5, insert the heptagonal protrusion 12 on the inner circumferential surface of the coil described in step 4 and 1 between the ta-curve 2 of the float.
11:1 laps on the float) Apply electricity to M, and add the mountain area so that the mountain 1 + "t 3 of the float becomes a mountain 'y'LI, 1, and the temperature is also high; After that, without adding υ1 to the mountain area, harden the "C tooth surface and tip along the mountain gata number plate.Ak Ia
Uniform and even? (V. Draw Yamanaka like this (
- To do this, maintain a predetermined distance between the inner peripheral surface of the coil coil including the above-mentioned protrusions and the mountain area surface of the mountain, the C surface, and the outlet surface.
The protrusion ζ1- is inserted between the peaks, and a predetermined high frequency type >

-Finally, when induction hardening the float, when the seven noules of the gear are Ill, the formula (Horozin's formula) r-6>' I (1
5/nr (112) is known, and the cyclic induction addition
In the JV coil - [- of the gear as shown in the figure, 1: The appropriate frequency determined by ζ according to the number, r! , ' If the frequency current is passed through 1 and 4, the gear will move from the starting point to 11, i bottom (I'11
The entire section will be given a uniform rate of one charge. 1. Higher than the above suitability 11-frequency. When a -il wave t, father, Q, -frequency current is applied, the hardened layer on the ridge surface is mainly bent as a result of the bending force of the crest. <, the hardened layer in the mountain area becomes thinner.

On the other hand, if a frequency lower than the appropriate frequency is used, the entire crest and tooth bottom will be heated, and the tooth root will be heated to a higher temperature than the tooth tip.
The hardened layer in the mountain area becomes thicker, but the entire mountain area is hardened.

Therefore, also in the case of the coil of the present invention, the triangular protrusion on the inner peripheral surface of the coil is made to resemble the tooth shape of a gear, and the frequency of the high-frequency current is lower than the appropriate frequency as described above, The base of the crest is heated to a higher temperature than the outer part, and at this time, the distance between the inner circumferential surface of the coil and the gear is too small for the crest area and the tooth surface, so that the bottom of the tooth is lower than the tip of the tooth. Although it is heated first, as will be described later, it is not cooled sufficiently during cooling, resulting in insufficient baking or uneven hardness. - If the force is too large, when the gear is heated by induction, the tooth surface and tooth tip will be heated earlier than the tooth tip.
I heated and the root of the tooth is not heated to 1-min, so the tooth + rc
The hardened layer at LJ becomes shallower. Sub-1) Therefore, the distance between the inner circumferential surface of the coil and the tooth bottom surface and the tooth surface is 0.3 to 1. OL (tooth thickness) is preferable. Also, the smell of the tips of the teeth (ha,:
)・If the distance from the E blood in the C hole is too small, the tip will be heated before the bottom of the tooth, and the entire peak will be heated evenly. The tip is not heated. Therefore, the distance ζ between the outlet surface and the inner circumferential surface of the coil is preferably 2.0 to 3.5 m (module).

Furthermore, high frequency ff5. The heating time with 'tAc is also important.

If the addition time is too long, the entire crest will be added (-), so the subsequent cooling will harden the entire crest,
・If the force, pressure, and JV time are too short, set the quenching temperature to 1.
It doesn't reach the ship. (Heating time is usually 0.5~1
The seconds range is amazing.

1. Use 11. Frequency of 1-frequency current, interval between rfi 'R and -2 inner periphery, and heating time. 2C. Temperature the bottom of the tooth higher than the tip of the tooth. After heating the tooth bottom, the tooth surface and tip are heated along the tooth profile, and then the coolant is directed toward the tooth bottom from the coolant injection hole provided in the groove between the triangular protrusions of the coil. Spray along the above protruding surface. As with conventional coils, the coolant can be uniformly injected in the radial direction from the inner surface of the coil, which is a circumferential surface, or, as mentioned above, the coolant can be injected from the inner circumferential surface formed in a corrugated shape in the normal direction. When cooling the gear by spraying coolant uniformly onto the gear, it is difficult to harden the gear uniformly, especially at the bottom of the tooth. However, by using the coil according to the present invention and injecting °C1 coolant toward the bottom of the tooth and along the surface of the projection with the triangular projection inserted in the tooth groove of the gear, the result shown in FIG. As shown, a hardened layer 4 having a uniform depth and hardness is formed on the tooth tip 1, tooth surface 2, and tooth edge 3.

In addition, when cooling with this coolant, the distance between the inner peripheral surface of the coil and the float is important, and the odor ζ on the tooth bottom and tooth surface is
If the gap is too small, the coolant will not flow well toward the tooth bottom (in particular, the hardening of the tooth bottom will be insufficient). It's amazing.

As described above, when the ridges 11 are subjected to the induction hardening process of the present invention, the ridges 11 are completely hardened by contour hardening, and the hardened layer is formed on the tooth bottom, tooth surface, and tooth tip. Both smells 'C and M
J- hardness and depth are hL, and the entire C11 part is hardened.
In particular, it can be suitably used for manufacturing small 1171-strength floats of up to about 4 ounces per unit.

The following is an example of quenching Yamanaka's ring 911 according to -I.1 of the present invention.

fruit! +i! It is 11th 21st, using a coil that is 15th
The distance between the J side and the mountain 1st curve and the mountain part are I and 5, respectively.
am and 21 and 7, sea urchin k, 2]・(distance between +1'd surface and destination surface 71111'(, 7yur 2
．． 5 spur gear with 1111 waves l tl I< I+
], , ulN l 2 K V , ゛tun AI
G, 5 A, JJII ρnormura-'il:il
+1.77~(1,8+sand strip 1'1 zeta high frequency heated shallow, cold Jolt/i'l, Toshishiki Soliful 3
As described above, the injection hole between the protrusions was sprayed for 3 to 4 seconds parallel to the tooth bottom (JJ), and then quenched and hardened.

Figure 6 shows the results of examining the hardness of each part of the tooth tip, tooth surface, and tooth bottom.Each part is hardened to a uniform hardness of 1-minute, so the gear is hard. As shown in FIG. 5, it is clear that contour hardening has been ideally performed along the tooth profile.

Comparative Example In the above example, the frequency was 150 KNz, the voltage was 10
The gear was induction hardened in the same manner except that the KV, current was 10 A, and heating time was 08 seconds. The tooth tip and tooth surface were heated before the tooth bottom, and while the hardened layer at the peak was thin, the hardened layer at the tooth bottom was thin.

Also, when the frequency is 10KHz or lower,
As the penetration depth increased, the length of time increased by one hour, so that the entire mountain portion was hardened.

[Brief explanation of drawings]

Fig. 1 shows the hardened layer of a float which has been entirely fired and hardened by a conventional coil, Fig. 2 is a plan view showing an embodiment of the coil according to the present invention, and Fig. 3 shows the inner periphery of the -+ C row. The main part of the song wo, 1, J' j, 1 m-,? 1) Figure 1 shows the (cod?
61. Shi! is 1
, Ushiaki's: J-il, l, "(4Q, j-kuniha") 1
1sa 11) j9 to 5 mountains 111! ) The outward appearance of “lji”
'11. and 4'ljsa13-'s leap 13--jX'Jg--go, (,ru.
- Hardened layer, 11...-2f, 12... square shape λ,
13... Bottom, 14 Pa λ bending, 15... Coolant jet f1
・1 hole. 'l'l 1. 'l +l l! ;I+! , h 4°
1,■(Meeting 1 Kobe made j and 11 agent Br I!f
! -, 1 Makino Ittsu Department Figure 1: 3 Figure 3 4111 31゛・・; ! 511 1156Figure J≧Qb-=TIElk Dommノ

Claims (1)

[Claims] (1) After placing the gear inside and heating it by induction, coolant is injected to i'J, 1 ton, and the gear is rapidly cooled and contour hardened using an annular high-frequency induction heating coil. ζ, It has triangular protrusions on the inner circumferential surface to engage with the tooth grooves of the float, and at the bottom between the ten protrusions, a coolant is applied toward the 1'11 bottom of the float and parallel to the protruding surface. I can do 1.
Yama JII's high INJ wave quenched steel, which is characterized by having one cooling injection hole opening in ).