JP2526275Y2 - Induction hardening device for crankshaft - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an induction hardening device for a crankshaft, and more particularly, to an induction hardening device suspended by a filament of a crankshaft.

[0002]

2. Description of the Related Art A conventional technique will be described below with reference to the drawings. FIG. 6 is a front view of an example of a crankshaft, FIG. 7 is a front view of a conventional induction hardening device for a crankshaft, and FIG. 8 is a part of a heating coil body mounted on a portion to be hardened. It is an enlarged front view. The crankshaft W shown in FIG. 6 is a crankshaft of a four-cylinder engine, and is composed of journals J1 to J5 and pins P1 to
Equipped with P4. W1 is a straight line connecting the centers of the respective journals J1 to J5, and is an axial center line serving as the center of rotation of the crankshaft W.

As shown in FIG. 7, a conventional induction hardening device for hardening a pin P1 of a crankshaft W is, for example,
A heating coil 10 of a semi-open saddle type or the like for high-frequency heating of P1, a pair of quenching liquid jet jackets 13 and 13 arranged below each side of the heating coil 10 so as to face each other, A heating coil body C provided with a lead conductor 11, an input terminal 14 provided at the upper end of the lead conductor 11, and a pair of coil side plates 12 (front side and back side in FIG. 7), and a high frequency And a transformer T for supplying a current. And
The heating coil 10, the lead conductor 11, the jacket 13, and the input terminal 14 are attached to the coil side plate 12.
The input terminal 14 is connected to and fixed to an output terminal 15 protruding from a lower portion of the transformer T so as to be able to contact and separate therefrom.

In order to prevent contact between the heating coil 10 and the pin P1 and to keep the gap distance between the heating coil 10 and the pin P1 constant during quenching of a portion to be quenched of the crankshaft W, for example, the pin P1. As shown in FIG. 8, a central spacer 17 is provided at a central portion of the heating coil 10, and side spacers 18 are provided at both sides of the heating coil 10. Both the spacers 17 and 18 are fixed to the coil side plate 12 by bolts 16.

In FIG. 7, reference numeral 23 denotes a transformer supporting member, which includes a horizontal member 23a and a vertical member 23b integrally formed with the horizontal member 23a at an end of the horizontal member 23a. The transformer T is a pantograph from the horizontal member 23a.
It is fixed on a base plate 21 suspended via a base 22.
The vertical member 23b is disposed above and below a pair of slidably fitted vertical rails 46 fixed to the front of a panel 40 called a power matching panel for supplying high frequency power to the transformer T. Slide guides 24, 24 are attached.

On the upper surface of the horizontal member 23a of the transformer support member 23, the lower end of a wire 33 wound around a pulley 32 which is pivotally supported at the tip of a stay 31 provided on the upper surface of the board 40 is fixed. The upper end of the wire 33 is connected via a spring 34 to one end of a bolt 35 screwed to a projection 49 provided on the upper surface of the board 40. A stay 41 is projected from the front surface of the board 40, and a vertical cylinder 42 for moving the rod 43 forward and backward is provided at the tip of the stay 41. The upper end of the rod 43 is in contact with a projection 23c provided on the vertical member 23b of the transformer support member 23.

In addition to the above, a cabtire cable (not shown) for supplying a high-frequency current from the panel 40 to the transformer T, a flexible pipe (not shown) for supplying a cooling liquid to the transformer T and the heating coil 10, and a jacket 13. A flexible piping (not shown) for supplying a quenching liquid is provided.

In order to quench the pin P1 of the crankshaft W, the crankshaft W is positioned so that the axis W1 is horizontal and the pin P1 is located below the heating coil C.
After that, the crankshaft W is rotated about the axis W1 to position the pin P1 at the top dead center. Next, when the rod 43 is retracted by operating the cylinder 42,
The transformer T and the heating coil C descend from the standby position. Then, the heating coil 10 is placed on the pin P1 that has entered between the pair of jackets 13 and then passed between the jackets 13. Next, when the crankshaft W is rotated, the center of the pin P1 moves on the circumference W2, so that the heating coil C and the transformer T swing vertically and horizontally.

[0009] While rotating the crankshaft W,
After applying a high-frequency current to the heating coil 10 through the transformer T for a predetermined time from 40, the quenching liquid is injected from the jacket 13 to the pin P1 while the rotation of the crankshaft W is continued, and the pin P1 is cooled. To complete the hardening of the pin P1. Thereafter, when the pin P1 reaches the top dead center, the rotation of the crankshaft W is stopped. Next, the cylinder 42 is operated, the rod 43 is advanced, and the heating coil C and the transformer T are raised to return to the original standby position. After that, the pins P2 to P4 are sequentially quenched in the same manner as the quenching of the pins P1, and then, if necessary, the heating coil C is replaced with a heating coil suitable for quenching the journals J1 to J5. The journals J1 to J5 are quenched sequentially.

[0010]

The conventional induction hardening apparatus for a crankshaft described above has the following problems. That is, during the quenching of the pin P1, which is the part to be quenched, for example, a load obtained by subtracting the tension of the spring 34 from the total weight of the heating coil C, the transformer T, and the transformer mounting member 23 is applied to the pin P1. However, the pin P1 during quenching is
Since the center revolves around the circumference W2,
The pin P1 moves up and down.

Therefore, the spring 34 also expands and contracts, and the tension of the spring 34, that is, the tension of the wire 33 also changes so that it becomes minimum at the top dead center of the pin P1 and becomes maximum at the bottom dead center. Therefore, the load applied to the pin P1 during quenching is maximum at the top dead center and minimum at the bottom dead center, but the fluctuation of the load applied to the quenched part during quenching of the quenched part such as the pin P1 If there is, the side spacers 18 are worn unevenly, and the distortion of the crankshaft W after quenching tends to increase.

If the load applied to the quenched portion is too large, not only the central spacer 17 and the side spacers 18 will be severely worn, but also the distortion of the crankshaft W after quenching may increase. Thus, it is necessary to reduce the load applied to the pin P1 during quenching by turning the bolt 35 to set the tension of the spring 34 to an appropriate magnitude. It has been empirically known that the magnitude of this load is usually within the range of 5 to 10 kg regardless of the size of the crankshaft. For example, the weight of the heating coil C is 30 kg.
In such a case, the tension of the spring 34 is set to 20 kg and the weight applied to the quenched portion is set to 10 kg.

However, when the type of the crankshaft changes and the size of the part to be quenched becomes large, it is necessary to use a large heating coil body, and the weight of the heating coil body naturally increases. , The tension of the spring 34 needs to be readjusted. In addition, when the weight of the heating coil body is extremely large, adjustment of the tension of the spring 34 is not sufficient,
You must replace it with a stronger spring. As described above, when replacing the heating coil body corresponding to the type of the crankshaft, adjusting the tension of the spring 34 or replacing the spring 34 is extremely troublesome.

The present invention has been made in view of the above circumstances, and the load applied to the quenched portion during quenching of the crankshaft is substantially constant, and the weight of the heating coil body is different. A high-frequency hardening device for crankshafts that can mechanically keep the load on the hardened part of the crankshaft within a predetermined range when replaced with another type without the need for human labor. It is intended to provide.

[0015]

In order to solve the above-mentioned problems, the induction hardening device for a crankshaft according to the present invention is mounted on a portion to be hardened of the crankshaft and heats the portion to be hardened by high frequency. Induction hardening of a crankshaft including a coil body, a transformer that is detachably attached to an upper portion of the heating coil body, and supplies a high-frequency current to the heating coil body, and a filament that suspends the transformer. In the device, a cylinder having a built-in piston, a rod having the piston fixed to one end and the upper end of the filament being connected to the other end protruding from the end of the cylinder, and a type of a heating coil body are detected. Means for adjusting the fluid pressure in the space surrounded by the piston, rod and cylinder in accordance with the type of the detected heating coil body.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. 1 to 5 are drawings for explaining the present embodiment. FIG. 1 is an explanatory front view, FIG. 2 is a cross-sectional view taken along line AA of FIG. 1, and FIG. 3 is a part of a heating coil body. FIG. 4 is an electric circuit diagram, and FIG. 5 is an explanatory front view of each heating coil body.
Note that the same components as those described in the related art are denoted by the same reference numerals.

The induction hardening apparatus according to the present embodiment is used by exchanging three types of heating coil bodies C1, C2 and C3 having different sizes and weights, for example, for quenching three types of crankshafts. can do. As shown in FIG. 5, the configuration of the heating coil body C1 is similar to that of the heating coil body C described in the related art, and includes a heating coil 101, a lead conductor 111, a coil side plate 121, an input terminal 14, and one pair. Jacket 131 is provided. Similarly, the heating coil body C2 includes a heating coil 102, a lead conductor 112, and a coil side plate 122.
, An input terminal 14, and a pair of jackets 132. Further, the heating coil body C3 also includes a heating coil 103, a lead conductor 113, a coil side plate 123, an input terminal 14, and a pair of jackets 133. Although not shown, of course,
The heating coil bodies C1, C2, and C3 each include a center spacer and side spacers as described in the prior art.

The induction hardening apparatus according to the present embodiment differs from the induction hardening apparatus described in the prior art only in the points described below, and the description of the same parts will be omitted. As shown in FIG. 1, the induction hardening device of the present embodiment is different from the conventional technology in that the spring 34 of the induction hardening device is replaced by a cylinder.
51 are provided. That is, the cylinder 51 is disposed substantially horizontally above the board 40, and the base 51a of the cylinder 51 is
It is rotatably attached to a projection 45 provided on a stay 44 fixed to the upper surface of 40. A piston 53 is slidably disposed in the cylinder 51.

Numeral 52 is a linear rod slidably penetrating the tip 51b of the piston 51. One end of the rod 52 is fixed to the piston 53, and the other end is a wire 33.
Is connected at the upper end. And piston 53, rod
52 and a space 54 surrounded by the cylinder 51 from the compressed air source 100 via a pipe 201, a pressure reducing valve 71, and a solenoid valve 61, or a pipe 202, a pressure reducing valve 72, and a solenoid valve.
Compressed air is supplied either via 62 or further via piping 203, pressure reducing valve 73 and solenoid valve 63.

The weights of the heating coil bodies C1, C2, and C3 are, for example, 30 kg, 40 kg, and 50 kg, respectively, and have different dimensions from each other.
The input terminals 14 of C2 and C3 have the same shape and the same dimensions so that they can be connected to the output terminal 15 of the transformer T. The pressure reducing valve 71 and the solenoid valve 61 correspond to the heating coil body C1, and the pressure reducing valve 72 and the solenoid valve 61
62 corresponds to the heating coil body C2. Also, the pressure reducing valve 73
And the solenoid valve 63 correspond to the heating coil C3. Assuming that the allowable load of the quenching pin P1 is 10 kg, when the effective pressure receiving area of the piston 53 is, for example, 20 cm ² , the discharge pressure of the pressure reducing valves 71, 72, and 73 is 1 kg / cm.
² , 1.5 kg / cm ² and 2 kg / cm ² .

As shown in FIG. 3, the heating coil bodies C1, C
2 and the side of each input terminal 14 of C3,
Dogs 81, 82, and 83 protrude. Dog 81, 82,
And 83 are input terminals for identification of the heating coil body.
They are provided at different positions on the 14 sides. Contactless limit switches 91, 92, and 93 corresponding to the dogs 81, 82, and 83 are provided on the lower surface of the base plate 21 on which the transformer T is mounted.

As shown in FIG. 4, the limit switch 91 and the solenoid valve 61 are connected in series to a power supply 200 via an electric wire 301. Similarly, limit switch 92 and solenoid valve 62
The limit switch 93 and the solenoid valve 63 are also connected in series to the power supply 200 via a wire 303, respectively.

Next, the quenching operation of the crankshaft W by the induction hardening apparatus of the present embodiment will be described. First, when the input terminal 14 of the heating coil C1 is connected to the output terminal 15 of the transformer T, the dock 81 opposes and approaches the limit switch 91 and the limit switch 91 is operated. As a result, the solenoid valve 61 is operated and opened. Then, the discharge pressure set at the pressure reducing valve 71 (1 kg /
cm ² ) is supplied into the space 54 of the cylinder 51, and a constant predetermined force (20 kg) toward the base 51 a of the cylinder 51 is constantly applied to the piston 53, so that the tension of the wire 33 ( 20kg) is always constant.

The quenching operation of the pin P1 is performed in the same manner as in the conventional induction hardening apparatus. However, as described above, the piston 53 is pushed toward the base portion 51a of the cylinder 51 with a constant predetermined force. Therefore, the tension of the wire 33 is also always a predetermined value, and the load (10 kg) applied to the pin P1 is always constant even if the pin P1 revolves during quenching and moves up and down.

When the type of the crankshaft is changed and the heating coil body C2 is used to harden a pin (not shown) of the crankshaft which is different from the crankshaft W, the heating coil body C1 is connected to the transformer T. Is released and the solenoid valve 61 is closed. Next, when the input terminal 14 of the heating coil C2 is connected to the output terminal 15 of the transformer T, the limit switch 92 is operated by the dog 82 of the heating coil C2, the solenoid valve 62 is opened, and the discharge set by the pressure reducing valve 72 is set. Compressed air having a pressure is supplied into the space 54 of the cylinder 51, and the piston 53 is forced by the base of the cylinder 51 with a constant magnitude greater than when using the heating coil body C1.
Since the wire 33 is always pushed in the direction of 51a, the tension of the wire 33 is always kept constant, and the load applied to this pin during quenching becomes constant. The same applies when a different kind of crankshaft, for example, a pin is quenched using the heating coil body C3.

In the above embodiment, the case of quenching the pin of the crankshaft W has been described as an example. However, in the case of quenching the journal, although the heating coil body does not move up and down, The device can be used. Further, in the above embodiment, the case where the heating coil body also performs the injection of the quenching liquid has been described, but the jacket is not attached or the quenching liquid is not injected from the jacket,
It can also be used only for heating. Further, in the above-described embodiment, the wire 33 wound around the pulley 32 is used as the striate, but the present invention is not limited to this, and a chain or the like wound around a sprocket may be used.

[0027]

As described above, according to the present invention, a heating coil body which is mounted on a quenched portion of a crankshaft and heats a quenched portion by high frequency, and can be connected to and separated from an upper portion of the heating coil body. A high-frequency quenching device for a crankshaft equipped with a transformer that supplies a high-frequency current to the heating coil body and that is attached to the heating coil body, a cylinder with a built-in piston, and a piston at one end. A rod fixed and connected to the upper end of the filament at the other end protruding from the end of the cylinder, means for detecting the type of heating coil body, and fluid pressure in the space enclosed by the piston, rod and cylinder Means for adjusting the temperature according to the detected type of the heating coil body.

Therefore, in the induction hardening apparatus for a crankshaft according to the present invention, the pressure of the fluid in the space surrounded by the piston, the rod and the cylinder is mechanically adjusted according to the weight of the heating coil body used. The fluid pressure within is always maintained at a regulated pressure. Therefore, since the fluid pressure applied to the piston, that is, the tension of the filament is always constant, a constant load is always applied to the quenched portion during the quenching of the quenched portion. Therefore, the occurrence of uneven wear of the spacer can be prevented, and the distortion of the crankshaft after quenching can be reduced.

When the heating coil body is replaced with another one, as described above, the fluid pressure in the space, and hence the tension of the filament, correspond to the replaced heating coil body. Since the tension is mechanically changed, the trouble of adjusting the tension of the spring or the time of replacing the spring, which is conventionally required, becomes unnecessary, and the time for hardening the crankshaft can be shortened.

[Brief description of the drawings]

FIG. 1 is an explanatory front view of one embodiment of the present invention.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is a perspective view of a part of the heating coil body according to the embodiment of the present invention;

FIG. 4 is an electric circuit diagram of one embodiment of the present invention.

FIG. 5 is an explanatory front view of each heating coil according to the embodiment of the present invention;

FIG. 6 is a front view of an example of a crankshaft.

FIG. 7 is an explanatory front view of a conventional induction hardening device for a crankshaft.

FIG. 8 is an enlarged front view of a part of the heating coil body in a state where the heating coil body is placed on a quenched portion.

[Explanation of symbols]

 33 Wire 51 Cylinder 52 Rod 53 Piston 61, 62, 63 Solenoid valve 71, 72, 73 Pressure reducing valve 81, 82, 83 Dog 91, 92, 93 Limit switch C1, C2, C3 Heating coil body P1 to P4 Pins J1 to J5 Journal T Transformer W Crankshaft

Claims (1)

(57) [Scope of request for utility model registration] 1. A heating coil body mounted on a quenched part of a crankshaft to heat the quenched part with high frequency, and a heating coil body attached to the upper part of the heating coil body so as to be able to contact and separate from the heating coil body. A high frequency quenching device for a crankshaft, comprising: a transformer for supplying a hydraulic fluid; and a filament that suspends the transformer, comprising: a cylinder having a built-in piston; wherein the piston is fixed to one end, and from the end of the cylinder. A rod having an upper end connected to the protruding other end, a means for detecting a type of a heating coil body, and a heating coil for detecting a fluid pressure in a space surrounded by the piston, the rod, and the cylinder An induction hardening device for a crankshaft, comprising: means for adjusting according to the type of body.