JP4405526B2 - Guide tip structure for high frequency induction heating coil - Google Patents

Description

  The present invention relates to a plurality of high frequency induction heating coil guide chips mounted between a pair of side plates that support a semi-open saddle type high frequency induction heating coil, wherein the journal portion or pin portion of the crankshaft is half open. Positioning of the center of the journal part or pin part with respect to the semi-open saddle type high frequency induction heating coil, and the journal part or pin between the counterweight parts adjacent to each other on the crankshaft Related to the structure of a guide tip for a high-frequency induction heating coil for positioning a semi-open saddle type high-frequency induction heating coil in the width direction of the part, and in particular, the range of erosion of a hardened hardened layer formed in a journal part or a pin part Is related to the structure of the guide tip for a high frequency induction heating coil that can sufficiently satisfy the standard value. That.

  As shown in FIG. 9, the crankshaft 1 that is an object to be heated includes a journal portion 2 that is a central axis, a counterweight portion 3 that is disposed between adjacent journal portions 2, and counterweight portions that face each other. The journal part 2 and the pin part 4 are subjected to high-frequency induction heating and quenching treatment. As this quenching method, there are flat quenching, fillet R quenching and the like, but in any case, the quench hardened layer needs to be correctly formed on the journal portion 2 and the pin portion 4. In addition, as a high frequency induction heating apparatus for high frequency induction heating of the journal part 2 and the pin part 4, what was conventionally shown by FIG. 1 of Unexamined-Japanese-Patent No. 2002-226919 (patent document 1) is employ | adopted conventionally. Has been.

  The high-frequency induction heating apparatus described in Japanese Patent Application Laid-Open No. 2002-226919 has an apparatus structure as shown in FIG. 1, but FIG. 10 uses a semi-open saddle type high-frequency induction heating coil 5 that approximates this. The high-frequency induction heating device 6 is shown.

As shown in FIG. 10, the high-frequency induction heating device 6 is supported by the side plate 7 and a pair of side plates 7 that are connected to the device main body side and arranged opposite to each other, and an opening on the lower end side of the side plate 7. A semi-open saddle type high frequency induction heating coil 5 and a predetermined position corresponding to the half open saddle type high frequency induction heating coil 5 (in this example, an upper part with respect to the center line of the journal part 2 of the crankshaft 1 and a journal) The high-frequency induction heating coil guide tips 8a, 8b, 8c, etc., which are disposed on the left and right sides of the center line of the portion 2 and attached to the side plate 7, are semi-open saddle type high-frequency induction heating coils 5. Is connected to a power supply lead conductor 9 and is provided with a cooling water supply means 10 for rapidly cooling the heating portion of the crankshaft 1. It should be noted that the high frequency induction heating coil guide tip 8a, 8b, when 8c performs high-frequency induction pressure heat by semi-open saddle type high frequency induction heating coil 5 a journal portion 2 of the crankshaft 1 (or pin portion 4), the journal portion 2 (or pin portion 4) and a member for securing a predetermined gap (about 0.5 mm to 3.5 mm) between the half-open saddle type high frequency induction heating coil 5, and these guide chips 8a, 8b , 8c so that the semi-open saddle type high frequency induction heating coil 5 is placed on the journal part 2 (or the pin part 4) rotated about the axis of the crankshaft 1 (center line of the journal part 2). It has become. At this time, the center of the journal part 2 (or the pin part 4) is positioned with respect to the semi-open saddle type high frequency induction heating coil 5 by the contact action of the guide tips 8a, 8b, 8c with the outer peripheral surface of the journal part 2. .

The high-frequency induction heating coil guide tips 8a, 8b, 8c provided in the conventional high-frequency induction heating device 6 having the above-described structure are usually formed as shown in FIGS. 11 (a) and 11 (b). That is, the side plates 7 and 7 arranged opposite to each other with the gap 11 interposed therebetween, the chips 12 and 12 arranged in contact with the inner surfaces of the side plates 7 and 7, and the chips 12 and 12 between them. The chip fixing plate 13 is interposed, and the side plates 7 and 7, the chips 12 and 12, and the screws 14 and 14 for fixing the chip fixing plate 13 in close contact with each other. Here, the width L ₁ between the outer surfaces of the chips 12 and 12 (see FIG. 11A) is a constant (not variable but fixed), and this width L ₁ is the journal portion of the crankshaft 1. 2 or the width dimension L ₂ or L _{3 of the} pin portion 4 (see FIG. 9) needs to be substantially equal.

However, if the width dimension L ₁ is made exactly the same as, for example, the width dimension L _{2 of the} journal section 2, the counterweights on both sides of the journal section 2 in order to place the guide chips 8 a, 8 b, 8 c on the journal section 2. Since it does not go smoothly when inserted between the portions 3 and 3, it is necessary to set L ₁ <L ₂ slightly. Even if a guide chip for a high-frequency induction heating coil having the same width dimension L ₁ as the width dimension L ₂ of the journal portion 2 of a certain type of crankshaft 1 is used, another type of crankshaft 1 having a substantially similar size. When the same high frequency induction heating coil guide tip is used together with the crankshaft 1 having the same outer diameter dimension and the width dimension slightly larger than L ₂ , the counterweight of the crankshaft 1 is used. A gap is generated between the portion 3 and the guide tip for the high frequency induction heating coil. FIG. 12A shows a situation in which a gap δ is generated between the outer surface of the chip 12 and the inner surface of the counterweight portion 3, and high frequency induction is performed with respect to the width dimension L ₂ of the journal portion 2. heating coil guide tip 8a (and 8b, 8c) the width L ₁ of which shows a case where a small gap δ is generated. In this case, the half-open saddle type high frequency induction heating coil 5 is located at a position shifted from the center position in the width direction of the journal portion 2 in the same manner as the guide tip 8a (and 8b, 8c) for the high frequency induction heating coil. It will be arranged facing the outer peripheral surface.

When the outer peripheral surface of the journal portion 2 is rotated by high-frequency induction while rotating the crankshaft 1 about its axis (center line of the journal portion 2) for flat quenching with the gap δ in this manner, FIG. As shown in b), the hardened and hardened layer S ₁ is formed at a position shifted from the center of the journal portion 2 in the width direction (for example, a position shifted to the right), and both end portions of the hardened and hardened layer S ₁ and the counterweight portion. This causes a problem that the dimensions α and β up to the inner surface 3 are not the same. The dimensions α and β is referred to as "baked fled range", but this is the dimensions are standard value is defined, is not satisfied occurs this Tadashi rated value.

Also, when performing fillet R quenching by high frequency induction heating of the outer peripheral surface of the journal portion 2 while rotating the crankshaft 1 about its axis, as shown in FIG. Since there is a gap δ between the guide tip 8a (and 8b, 8c) and the counterweight portion 3 of the crankshaft 1, the high frequency induction heating coil guide tip 8a (and 8b, 8c) in the width direction of the journal portion 2 is used. When positioning is not performed correctly, semi-open saddle type high frequency induction heating coil 5 is also not performed correctly positioned, as shown in FIG. 12 (d), the corner portion of the hardened layer S ₂ formed by fillet R hardening A difference occurs between the hardened layer depths t ₁ and t _{2 at,} and the standard value may not be satisfied.

  The present invention has been made to solve the above-described problems, and its purpose is to always correctly position the guide tip for the high-frequency induction heating coil in the width direction of the journal portion or pin portion of the crankshaft. As a result, the positioning of the half-open saddle type high frequency induction heating coil 5 in the width direction described above can always be performed correctly. In the case of flat quenching, the range of flank escaping, and in the case of fillet R quenching, An object of the present invention is to provide a guide chip structure for a high-frequency induction heating coil that can satisfy the standard value of the quenching depth in the corner portion of the quench-hardened layer and can perform precise quenching.

In order to achieve the above-described object, the present invention provides a plurality of guide chips for high-frequency induction heating coils respectively attached between a pair of side plates that support a semi-open saddle type high-frequency induction heating coil, When the journal part or the pin part is subjected to high-frequency induction heating by the half-open saddle type high-frequency induction heating coil, positioning of the center of the journal part or pin part with respect to the half-open saddle type high-frequency induction heating coil, and the crankshaft In the structure of a guide tip for a high frequency induction heating coil for positioning the semi-open saddle type high frequency induction heating coil in the width direction of the journal portion or pin portion between adjacent counterweight portions, the high frequency induction heating coil The guide tip has a spring function provided on each of the pair of side plates. Comprising a pair of flexible members, a pair of chips which are fixed respectively disposed inside the pair of flexible bodies facing each other, and a pair of chip fixing plate fixed respectively arranged on the inner side of the pair of chips, The flexible body is integrated with the side plate by forming a pair of slits in the side plate that extend to the opening of the side plate where the journal portion or the pin portion is inserted and are opposed to each other with a gap therebetween. In a free state in which the guide chip for the high frequency induction heating coil is not inserted between the counterweight portions adjacent to each other, there is a gap between the inner surfaces of the pair of chip fixing plates facing each other. And the width dimension between the outer surfaces of the pair of chips facing each other is set larger than the width dimension of the journal part or the pin part, As the coil guide chip is inserted between the counterweight portions adjacent to each other, the gap between the inner surfaces of the pair of chip fixing plates is narrowed by the spring function of the pair of flexible bodies, Alternatively, the gap is eliminated.
Also, in the present invention, the high-frequency induction heating coil guide tip arranged at three positions on the upper side and right and left sides with respect to the center line of the journal portion or a pin portion, these for three high-frequency induction heating coil guide The flexible body is provided in all or at least one of the three places where the chips are arranged.

In the first aspect of the present invention, the guide chip for the high frequency induction heating coil is fixed to the inside of the pair of flexible bodies provided on the pair of side plates and having a spring function, and the pair of flexible bodies facing each other. A pair of chips arranged and a pair of chip fixing plates fixedly arranged inside the pair of chips, extending to the opening of the side plate in which the journal part or pin part is inserted, and spaced apart By forming a pair of slits facing each other on the side plate, the flexible body is integrally provided on the side plate, and the guide chip for the high frequency induction heating coil is not inserted between the counterweight portions adjacent to each other. In this configuration, a gap is present between the inner surfaces of the pair of chip fixing plates facing each other, and the width dimension between the outer surfaces of the pair of chips facing each other is The width of the journal portion or the pin portion of the shaft is set to be larger, and the guide tips for the high frequency induction heating coil are inserted between the counterweight portions adjacent to each other on the crankshaft, so that the pair of tip fixing plates Since the gap between the inner surfaces is narrowed by the spring function of the pair of flexible bodies or the gap is eliminated, according to the guide chip structure for a high frequency induction heating coil of the present invention, the following An effect can be produced. That is, since the guide chip for the high frequency induction heating coil is made of flexible material (variable width), it is used for the high frequency induction heating coil between the counterweight portions adjacent to each other in the width direction of the journal portion or the pin portion. When the guide chip is inserted, the guide chip for the high frequency induction heating coil having a width dimension larger than the width dimension between the counterweight portions adjacent to each other when the guide chip is in a free state is caused by the spring function of the flexible body of the side plate. The gap between the inner surfaces of the pair of chip fixing plates is elastically deformed so that the pair of chips are inserted and arranged between the counterweight portions adjacent to each other, and are pressed against each counterweight portion. Accordingly, it is possible to always correctly position the guide chip for the high frequency induction heating coil in the width direction of the journal portion or the pin portion between the counterweight portions adjacent to each other. The open saddle type high frequency induction heating coil can always be accurately positioned. Thereby, the burning escape range can be stably within the standard value. Further, the same guide chip for a high frequency induction heating coil can be obtained by appropriately setting the flexible range of the above-mentioned flexible body even for a crankshaft having the same outer diameter dimension or slightly different width dimension of the journal part or the pin part. It is also possible to use together.

According to the first aspect of the present invention , by forming a pair of slits in the side plate that extend to the opening of the side plate in which the journal portion or the pin portion is inserted and are opposed to each other with a gap therebetween. Since the flexible body is provided integrally with the side plate, there is no need to provide a flexible body made of a member separate from the side plate, and therefore , the manufacture of the high-frequency induction heating device can be facilitated. it can.

  According to the third aspect of the present invention, the guide tips for the high frequency induction heating coil are arranged at three positions on the upper side and the left and right sides with respect to the center line of the journal portion or the pin portion, and the three high frequency induction heating portions are arranged. Since the flexible body is provided at all or at least one of the three locations where the coil guide tips are arranged, the journal portion or the pin portion of the journal portion or the pin portion is made flexible by making all of the above three locations flexible. Of course, the positioning of the guide chip for the high frequency induction heating coil in the width direction and the positioning of the half-open saddle type high frequency induction heating coil can be ensured, but the above-described positioning in the width direction can be achieved by simply making at least one point flexible. Can be carried out correctly, and it becomes possible to set the range of the burnout within the standard value.

  Hereinafter, the structure of a guide chip for a high-frequency induction heating coil according to an embodiment of the present invention will be described with reference to FIGS. 1 to 8, the same parts as those in FIGS. 9 to 12 are denoted by the same reference numerals, and redundant description is omitted.

  FIG. 1 shows a high-frequency induction heating device 20 having a structure of a guide chip for a high-frequency induction heating coil according to an embodiment of the present invention. The high-frequency induction heating device 20 is a journal part of a crankshaft 1. 2 is subjected to high frequency induction heating. As shown in FIG. 1, the high-frequency induction heating device 20 is disposed in a pair of side plates 7 that are respectively connected to a transformer (not shown) side and arranged to face each other, and an opening on the lower edge side of these side plates 7. A semi-open saddle type high frequency induction heating coil 5 supported by the side plate 7; a power supply lead conductor 9 for supplying high frequency power to the half open saddle type high frequency induction heating coil 5 from a power source not shown; A predetermined position of the side plate 7 corresponding to the high-frequency induction heating coil 5 (in this embodiment, on the upper side with respect to the center line of the journal part 2 of the crankshaft 1 and on the left and right side parts with respect to the center line of the journal part 2). 3 high frequency induction heating coil guide tips 21a, 21b, 21c and the like attached at three locations. Further, the high-frequency induction heating device 20 is provided with a cooling water supply means 10 for injecting cooling water for quenching treatment to the journal portion 2 that has been induction-heated by the semi-open saddle type high-frequency induction heating coil 5. It constitutes an induction hardening apparatus. FIG. 2 is a front view of the side plate 7 showing the structure of the three high frequency induction heating coil guide tips 21a, 21b, and 21c that are the main elements of the present embodiment.

  Three high frequency induction heating coil guide chips 21a, 21b, and 21c, which are respectively attached between the pair of side plates 7 and 7 that support the semi-open saddle type high frequency induction heating coil 5, are configured to halve the journal portion 2 of the crankshaft 1. When high frequency induction heating is performed by the open saddle type high frequency induction heating coil 5, in order to ensure a predetermined gap between the journal part 2 and the half open saddle type high frequency induction heating coil 5, the journal part is provided by a rotary drive mechanism (not shown). The journal portion 2 that is rotationally driven about the center line 2 is disposed in contact with the upper and left and right side portions of the journal portion 2. Specifically, as shown in FIGS. 1 and 2, one guide tip 21 a out of the three high-frequency induction heating coil guide tips 21 a, 21 b, 21 c is the center of the journal portion 2 of the crankshaft 1. The other two high frequency induction heating coil guide tips 21 b and 21 c are arranged on the left and right sides with respect to the center line of the journal portion 2. As the three high frequency induction heating coil guide tips 21 a, 21 b, 21 c are brought into contact with the outer peripheral surface of the journal portion 2, the center of the journal portion 2 with respect to the half-open saddle type high frequency induction heating coil 5 is Positioning is made.

  3A and 3B show the detailed structure of the guide chip 21a for the high-frequency induction heating coil used in the high-frequency induction heating device 20, and FIG. 3B shows the guide for the high-frequency induction heating coil. It is a front view of the chip | tip 21a, Fig.3 (a) is the sectional view on the AA line in FIG.3 (b). The other high-frequency induction heating coil guide tips 21b and 21c differ from the high-frequency induction heating coil guide tip 21a in the arrangement position and direction, but the structure is substantially the same. Description is omitted.

As shown in FIG. 2, a semicircular opening 22 into which the journal portion 2 of the crankshaft 1 is inserted is formed in the lower part of the side plates 7 and 7, as shown in FIGS. 3 (a) and 3 (b). Of the high-frequency induction heating coil guide chip 21a, 21b, 21c having a simple structure projecting into the semicircular arc opening 22 described above, the upper side and the left and right side parts of the semicircular arc opening 22 of the side plates 7, 7. (In other words, it is disposed at a location on the upper side with respect to the center line of the journal portion 2 and on both the left and right sides with respect to the center line). More specifically, a pair of parallel slits 23 and 23 extending upward from the semicircular arc opening 22 are formed on the upper side of the semicircular arc opening 22 of the side plates 7 and 7, respectively. A portion between the pair of slits 23, 23 (a cantilever plate having a spring function) is provided as a flexible body 24a, and on the left and right side portions of the semicircular arc opening 22 of the side plates 7, 7. Each of the slits 25 and 26 extending from the semicircular arc opening 22 to the left and right sides is formed, and side plate portions adjacent to the slits 25 and 26 are provided as flexible bodies 24b and 24c, respectively. And the guide chip 21a for high frequency induction heating coils is attached between the flexible bodies 24a, 24a of the side plates 7, 7, and between the flexible bodies 24b, 24b of the side plates 7, 7, and the flexible bodies 24c, Between 24c, high frequency induction heating coil guide tips 21b and 21c are respectively attached. Accordingly, in the present embodiment, all of the three high frequency induction heating coil guide tips 21a, 21b, and 21c are configured to be flexible. In FIG. 1, reference numerals 27 and 27 denote auxiliary side plates, and the side plates 7 and 7 are provided with only one slit 25 and 26 (see FIG. 2). As in the case of the slits 23, 23, two parallel slits of the side plates 7, 7 may be provided to sandwich the flexible bodies 24 b , 24 c .

On the other hand, as shown in FIGS. 1 to 4, the high frequency induction heating coil guide chip 21a includes a pair of opposing flexible bodies (flexible plates) 24a and 24a that are made flexible by the slits 23 and 23. Chips 29a, 29a, which are fixed in close contact with the inner surfaces of the respective flexible bodies 24a, 24a and whose distal end bulges from the flexible bodies 24a, 24a and protrudes from the outer surfaces of the flexible bodies 24a, 24a; these chips 29a, chip fixing plate 30a which is closely fixed to the inner surface of 29a, is composed of a 30a or the like, flexible body 24a, a 24a and the chip 29a, 29a and the chip fixing plate 30a, 30 a fixed Are separately performed by a pair of screws 31a and 31a at locations facing each other. The side plate 7 and the flexible body 24a are made of spring copper alloy (in this embodiment, phosphor bronze, beryllium copper, etc.), the chip fixing plate 30a is mainly made of brass material, and the chip 29a is made of ceramic. It is not limited to.

Further, as shown in FIG. 3A, in the high frequency induction heating coil guide chip 21a, the chip fixing plates 30a, 30a are not inserted between the counterweight parts 3, 3 adjacent to each other. A gap 32 is formed between the inner surfaces. The flexible body 24a is flexible in a direction in which the gap 32 is narrowed with a position indicated by reference numeral P in FIGS. 3A and 3B as a fulcrum, and therefore, the flexible bodies 24a and 24a and these flexible bodies. The chips 29a and 29a and the chip fixing plates 30a and 30a, which are separately fixed to the screws 24a and 24a by the screws 31a and 31a, are flexible with the position indicated by the reference symbol P as a fulcrum, and the elastic bodies 24a and 24a are elastic. It can be elastically deformed. As shown in FIG. 3A, when the high-frequency induction heating coil guide tip 21a is in a free state, the width dimension W ₁ between the outer surfaces of the tips 29a and 29a (FIG. 3A and FIG. 4). (See (a)) is set to be larger than the width L ₂ of the journal portion 2 of the crankshaft 1 (see FIGS. 4A, 4B, and 9). In this case, if the width of the gap 32 under the above-mentioned free state is W ₂ (see FIGS. 3A and 4A), the setting is made so that (W ₁ −L ₂ ) ≦ W _2. Has been.

On the other hand, the structure of the guide tip for the high frequency induction heating coil used when the pin portion 4 of the crankshaft 1 is subjected to high frequency induction heating is the same as that of the above-described guide tip 21a for the high frequency induction heating coil, and the description thereof will be omitted. Of course, with respect to the pin portion 4 of the crankshaft 1, the width dimension (not shown) between the outer surfaces of the pair of tips of the high frequency induction heating coil guide tip is determined by the counterweight portions 3 and 3 on both sides of the pin portion 4. Is set larger than the width L ₃ (see FIG. 9).

Next, the operation when the journal part 2 of the crankshaft 1 is induction-heated by the high-frequency induction heating device 20 including the high-frequency induction heating coil guide tips 21a, 21b, 21c will be described. First, in high frequency induction heating of the journal portion 2 of the crankshaft 1, the high frequency induction heating device 20 is lowered by an elevating mechanism (not shown) so that the journal portion 2 is disposed in the semicircular opening 22 of the side plate 7. The journal portion is inserted by inserting the tip portions of the high frequency induction heating coil guide tips 21a, 21b, 21c (for example, the tip portions of the pair of tips 29a, 29a) between the counterweight portions 3, 3 of the crankshaft 1. 2 is brought into contact with the outer peripheral surface. At this time, as described above, the width dimension W ₁ of the guide chips 21a, 21b, 21c for the high frequency induction heating coil in the free state is set to be larger than the width dimension L ₂ between the counterweight parts 3, 3 of the journal part 2. (W ₁ > L ₂ ) (see FIG. 4 (a)), the flexible bodies 24a, 24a, etc. are elastically deformed with the point indicated by the symbol P (see FIGS. 3 (a), (b)) as a fulcrum. , the 4 respective guide tip 21a as shown in (b), 21b, the width W ₃ is narrower than the width W ₂ of the gap 32 under clearance 32 is in a free state of the 21c. In this case, since the flexible body 24a is elastically deformed and the gap 32 is narrowed, the pair of chips 29a, 29a, etc. of the high-frequency induction heating coil guide chips 21a, 21b, 21c are connected to the pair of flexible bodies 24a, are pressed by the elastic restoring force such as 24a (elastic force in the direction in which the width W ₃ extends) to the inner surface of both sides of the counterweight portions 3 and 3 of the journal portion 2, as a result, the guide for the high-frequency induction heating coil tip 21a, 21b, Thus, 21c and the half-open saddle type high frequency induction heating coil 5 are positioned at the correct position in the width direction of the journal portion 2. That is, the half-open saddle type high frequency induction heating coil 5 is positioned at the center position in the width direction in the width direction of the journal portion 2 between the counterweight portions 3 and 3 adjacent to each other.

  Under such a state, the crankshaft 1 is rotationally driven by a rotation driving mechanism (not shown) around its axis (center line of the journal portion 2), and also high-frequency induction by a high-frequency induction heating coil tracking mechanism (not shown). The heating device 20 and thus the guide tips 21a, 21b, 21c and the semi-open saddle type high frequency induction heating coil 5 are held so as to follow the journal portion 2 in the rotating state. Is heated by high frequency induction. Thereafter, a quenching process is performed by injecting cooling water from the cooling water supply means 10 onto the journal portion 2 that has been induction-heated to a required quenching temperature to form a quench hardened layer.

FIG. 5 shows the quench hardening formed when the portion 35 of the journal portion 2 without the oil holes 34 is subjected to high frequency induction heating using the above-described high frequency induction heating coil guide tips 21a, 21b, and 21c and subjected to quenching treatment. shows the layer S _3, 6, a part 37 of the oil hole 36 of the journal portion 2 there is high frequency induction heating coil guide tip 21a described above, 21b, when quenching treatment by high-frequency induction heating using 21c It shows the hardened layer S ₄ to be formed. 7 shows the burn-out range in the portion 35 shown in FIG. 5, and FIG. 8 shows the burn-out range in the portion 37 shown in FIG. In FIGS. 7 and 8, the horizontal axis is the quenching site, the vertical axis is the burnout range, and the standard value of the burnout range is 3.0 to 4.5 mm. In FIGS. 7 and 8, when □ is a conventional high frequency induction heating coil guide tip 8a, 8b, 8c (see FIG. 12), ◇ and ○ are high frequency induction heating coil guide tips of the present embodiment. 21a, 21b, are those in the case of using 21c, ◇ those flexible body 24a, the spring constant of 24a such low (spring constant = 5.9kg / mm), ○ is flexible body 24a, a 24a such Those having a high spring constant (spring constant = 7.8 kg / mm) are shown. Here, the points marked with □, ◇, ○ are the average values of the measured flank range, and the upper end of the straight line extending upward from these is the highest measured value of the flank range, and below this The lower end of the straight line extending to the bottom is the lowest measured value of the burnout range. On the other hand, the quenching sites are the second journal portion 2 (2J) from the left of the crankshaft 1 shown in FIG. 9 and the fourth journal portion 2 (4J) from the left of the crankshaft 1 shown in FIG. The diameter of the second journal part 2 (2J) is 76.8 mm and its width is 24.0 mm, and the diameter of the fourth journal part 2 (4J) is 76.8 mm and its width is Therefore, the fourth journal portion 2 (4J) is slightly narrower (−0.5 mm) than the second journal portion 2 (2J).

  As shown in FIG. 7, when the conventional high frequency induction heating coil guide tips 8a, 8b, 8c are used, the second journal portion 2 (2J) exceeds the lower limit value, and the fourth journal The portion 2 (4J) is within the specified value, but when the high-frequency induction heating coil guide tips 21a, 21b, and 21c of the present embodiment are used, they are sufficiently within the standard value. I understand that. Further, in the portion 37 where the oil hole 36 of the journal portion 2 is present, there is a tendency that the variation in the burnout range is relatively large, but from FIG. It can be seen that when the high-frequency induction heating coil guide tips 21a, 21b, and 21c of the present embodiment are used, the “burn-out range” is sufficiently within the standard value.

5 and 6 show the hardened and hardened layers S ₃ and S ₄ formed when the high-frequency induction heating coil guide tips 21a, 21b, and 21c of this embodiment are used as described above. However, the hardened and hardened layers S ₃ and S ₄ are formed at almost correct positions in both the portion 35 of the journal portion 2 having no oil holes 34 and the portion 37 of the journal portion 2 having the oil holes 36. It was confirmed.

Although one embodiment of the present invention has been described above, the present invention is not limited to this embodiment, and various modifications and changes can be made based on the technical idea of the present invention. For example, in the embodiment described above, the journal portion 2 of the crankshaft 1 is subjected to quenching treatment by high-frequency induction heating using the high-frequency induction heating coil guide tips 21a, 21b, and 21c. The present invention can also be applied to the case where the portion 4 is subjected to quenching treatment by high-frequency induction heating using the high-frequency induction heating coil guide tips 21a, 21b, and 21c. In the embodiment described above, the three high-frequency induction heating coil guide tips 21a, 21b, and 21c are configured to be flexible. However, only one of them may be configured to be flexible. Good. Also in this case, it is possible to correctly position the guide chip for the high-frequency induction heating coil and thus the half-open saddle type high-frequency induction heating coil in the width direction of the journal part or the pin part. In the above-described embodiment, three high frequency induction heating coil guide tips 21a, 21b, and 21c are used. However, two or four or more high frequency induction heating coil guide tips can be used. is there. Further, in the above-described embodiment, when the high frequency induction heating coil guide chips 21a, 21b, 21c are inserted between the counterweight portions 3, 3 adjacent to each other, the chip fixing plates 30a, 30a facing each other are arranged. The gap 32 is narrowed to the width W ₃ (see FIG. 4B)), but the gap 32 may be set to zero (the gap 32 does not exist). . In the above, the structure of the guide chip for a high frequency induction heating coil according to the present invention has been described. However, this guide chip structure is not limited to the above-mentioned structure, and of course the same technical category is applied. .

It is a front view which shows the high frequency induction heating apparatus provided with the structure of the guide chip for high frequency induction heating coils which concerns on one Embodiment of this invention. It is a front view of the side plate which shows the state which attached the guide chip for high frequency induction heating coils to the side plate of the high frequency induction heating apparatus of FIG. 3 shows the structure of a guide chip for a high-frequency induction heating coil according to the present invention, and FIG. 3A is a cross-sectional view of the guide chip for a high-frequency induction heating coil, which is a cross-sectional view taken along line AA in FIG. FIG.3 (b) is a side view of the attachment location of the guide chip for high frequency induction heating coils to a side plate. FIG. 4A shows the relationship between the guide tip for a high-frequency induction heating coil and the journal portion and counterweight portion of the crankshaft, and FIG. 4A is a sectional view showing the guide tip for the high-frequency induction heating coil in a free state. (B) is sectional drawing which shows the state by which the guide tip for high frequency induction heating coils was inserted and arrange | positioned between the counterweight parts adjacent to each other. It is sectional drawing which shows the state which formed the hardening hardening layer in the part without an oil hole of a journal part using the guide chip for high frequency induction heating coils of this embodiment. It is sectional drawing which shows the state which formed the hardening hardening layer in the part with the oil hole of a journal part using the guide chip for high frequency induction heating coils of this embodiment. It is a graph which shows the burning escape range in the part without an oil hole of a journal part using this embodiment and the conventional high frequency induction heating coil guide tip. It is a graph which shows the burning range in the part with an oil hole of a journal part using this embodiment and the conventional high frequency induction heating coil guide tip. It is a side view of a crankshaft. It is a side view which shows the principal part of the high frequency induction heating apparatus which has a guide chip for high frequency induction heating coils of the conventional structure. FIG. 11A shows a structure of a conventional guide chip for a high-frequency induction heating coil, and FIG. 11A is a cross-sectional view of the guide chip for a high-frequency induction heating coil, and is a cross-sectional view taken along line BB in FIG. 11 (b) is a side view of the guide chip for the high frequency induction heating coil. It is sectional drawing which shows the quenching method of the journal part of the crankshaft using the guide chip for high frequency induction heating coils of the conventional structure, Fig.12 (a) is sectional drawing which shows the condition of flat quenching, FIG.12 (b) Is a cross-sectional view showing a hardened hardened layer formed in the journal part by flat quenching, FIG. 12C is a cross-sectional view showing the state of fillet R quenching, and FIG. 12D is a journal part by fillet R quenching. It is sectional drawing which shows the hardening hardening layer formed in.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Crankshaft 2 Journal part 3 Counterweight part 4 Pin part 5 Half open saddle type high frequency induction heating coil 7 Side plate 20 High frequency induction heating apparatus 21a, 21b, 21c Guide chip for high frequency induction heating coil 22 Semicircular arc opening 23 Slit 24a , 24b, 24c Flexible body 25, 26 Slit 29a Chip 30a Chip fixing plate 31a Screw 32 Gap

Claims (2)

A plurality of high frequency induction heating coil guide chips each mounted between a pair of side plates supporting a half open saddle type high frequency induction heating coil, wherein the journal portion or pin portion of the crankshaft is connected to the half open saddle type high frequency induction coil When high-frequency induction heating is performed by a heating coil, positioning of the center of the journal part or the pin part with respect to the semi-open saddle type high-frequency induction heating coil, and the journal part between adjacent counterweight parts of the crankshaft or In the structure of the guide chip for the high frequency induction heating coil for positioning the semi-open saddle type high frequency induction heating coil in the width direction of the pin portion,
The high frequency induction heating coil guide chip includes a pair of flexible bodies each having a spring function provided on the pair of side plates, and a pair of chips fixedly disposed inside the pair of flexible bodies facing each other. A pair of chip fixing plates fixedly arranged inside the pair of chips,
The flexible body is integrated with the side plate by forming a pair of slits in the side plate that extend to the opening of the side plate where the journal portion or the pin portion is inserted and are opposed to each other with a gap therebetween. Provided,
In a free state where the guide chip for the high frequency induction heating coil is not inserted between the counterweight portions adjacent to each other, a gap is formed between the inner surfaces of the pair of chip fixing plates facing each other. The width dimension between the outer surfaces of the pair of chips facing each other is set larger than the width dimension of the journal part or the pin part,
As the guide chip for the high frequency induction heating coil is inserted between the counterweight portions adjacent to each other, the gap between the inner surfaces of the pair of chip fixing plates serves as a spring function of the pair of flexible bodies. It was narrowed by or configured to eliminate the gap,
The structure of a guide tip for a high-frequency induction heating coil characterized by The high-frequency induction heating coil guide tips are arranged at three locations on the upper side and the left and right sides with respect to the center line of the journal portion or the pin portion, and three locations where these three high-frequency induction heating coil guide tips are arranged. structure of the guide chip for high frequency induction heating coil of claim 1, wherein all or at least one location to the provision of the flexible member.

Images