JPH0644505Y2 - Dummy pusher for induction heating device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention relates to a dummy pusher for an induction heating device. INDUSTRIAL APPLICABILITY The present invention can be used, for example, in a dummy pressing tool used in an induction heating device that induction-heats a work that is a forging material during hot forging.

[Prior Art] In recent years, in the field of processing, for example, the field of hot forging, an induction heating device is used as a means for heating a work, which is a forging material, to about 1000 to 1200 ° C before hot forging. As this induction heating device, an induction heating device in which a suitable number of induction heating furnaces are arranged in series and a pinch roller for supplying a work is arranged on the inlet side of the induction heating furnace is used. In this induction heating device, a work conveyed by a conveyor device is bitten by a pinch roller, and the work is sent into the induction heating furnace by rotation of the pinch roller. Then, the work is sequentially inserted into the induction heating furnace from the inlet of the induction heating furnace to induction-heat the work, and the work is sequentially discharged from the outlet of the induction heating furnace. In this induction heating device, since the works are successively fed into the induction heating furnace by the rotation drive of the pinch rollers, the front works sent into the induction heating furnace are pushed to the rear works sent one after another. It is sent out and sent to the exit side of the induction heating furnace.

By the way, in the induction heating device, if there is a gap between the work in the induction heating furnace, the magnetic flux for generating the induction current tends to concentrate on the end surface of the work, so the end surface of the work is Compared with the above, it is easy to overheat and reach a high temperature, and therefore there is a limit in ensuring the uniformity of hot forging. In this respect, as described above, in the induction heating apparatus of the type in which the front work is pushed out by the rear work, the work in the induction heating furnace is pushed out by the pinch rollers one after another and sent to the outlet side. Therefore, the end surface of the rear end of the front side work is pushed and closely contacted with the end surface of the front end of the rear side work, and there is substantially no gap between the adjacent works. Since the induced current is generated, the concentration of magnetic flux on the end surface of the work can be eliminated as much as possible, and since the end surface of the adjacent work and the end surface of the work are in close contact, heat transfer between the works can be expected, Therefore, the problem of overheating of the end surface of the work can be improved.

However, the end face of the front end of the work, which is successively fed into the induction heating furnace by the rotation drive of the pinch roller, is brought into close contact with the end face of the rear end of the work in the induction heating furnace so that the work exits from the induction heating furnace. However, there is a problem that the work will always remain in the induction heating furnace when heating is completed after heating a predetermined number of works, and there is a problem of burning waste, which is disadvantageous in terms of power consumption of the induction heating furnace. is there.

In order to solve the problem that the work remains in the induction heating furnace as described above, conventionally, a dummy rod made of stainless steel or refractory material was attached to the rear end of the last work, and the dummy rod was driven by rotation of a pinch roller. It is supplied into the induction heating furnace, which pushes the end face of the rear end of the last work with the dummy rod,
Therefore, the last work was to be discharged from the outlet of the induction heating furnace.

[Problems to be solved by the invention] However, in the case of a dummy rod made of stainless steel, the following problems occur. That is, first, since the dummy rod attached to the rear end of the work is made of stainless steel and is induction-heated, power consumption is wasted. Secondly, the length of the dummy rod requires a total length of the length of the induction heating furnace and the size of the bite for biting into the pinch roller. Therefore, the dummy bar is very long, for example, 3 to 5 m. This tends to be the case, so take up a lot of space for installing dummy rods.
Third, since the dummy rod is long, the dummy rod is thermally deformed and bent as it is used.

Further, in the case of a dummy rod made of a refractory material, firstly, since the refractory material is weak in bending, it is not easy to manufacture a dummy rod having a long length that can be practically used. Secondly,
Since it is a refractory material, it lacks heat transfer, and the heat at the rear end of the last work is not transferred to the dummy rod.Therefore, the temperature of the rear end of the last work is compared to the temperature of the rear end of other works. Usually 50
The temperature rises up to ~ 80 ° C, causing uneven temperature of the work, which is disadvantageous for accurate forging.

The present invention has been made in view of the above-mentioned circumstances, and an object thereof is to improve the problem of power consumption, the problem of bending due to thermal deformation, and the problem of overheating of the temperature of the end surface of the rear end of the work. It is to provide a dummy pusher for a heating device.

[Means for Solving the Problems] The induction heating device dummy pusher of the present invention is inserted into a passage of the induction heating device through which the work passes, and is made of ceramics and has a flexible heat resistance. At least two intermediate dummy bodies having a refractory material and a through hole through which the heat-resistant filament is inserted and having a refractory material as a base material, and a leading dummy which is connected to the tip portion of the heat-resistant filament and at least the tip portion is made of metal. It is characterized by being composed of the body.

Further explanation will be added. The cords are long and thin with flexibility. Typical ropes and chains are ropes. The length of the cord is appropriately set according to the length of the induction heating device and the like. As the ceramics that are the base material of the cord,
Although it is appropriately selected in consideration of heat resistance, tensile strength, price, etc., generally, an alumina type or an alumina-silica type can be used. When an alumina-silica ceramic rope is used as the heat-resistant cord, its composition can be, for example, 45 to 60% by weight of alumina and 40 to 55% by weight of silica. In addition to alumina-silica, the third
As a component, calcia (CaO), magnesia (MgO), may be used after addition of Kuromiya (Cr ₂ O _3). The diameter of the ceramic rope can be appropriately selected as necessary in consideration of heat resistance, tensile strength, etc., for example, 5
It can be about 60 mm. The bulk density of the ceramic rope can be set to 0.32 g / cm ² , for example. The tensile strength before heating of the ceramic rope may be, for example, 60 to 80 kg 25φ.

The intermediate dummy body has a through hole through which the heat-resistant cord is inserted.
The number of intermediate dummy bodies is appropriately selected according to the length of the induction heating device and the like, and is, for example, 2 to 8. The intermediate dummy body is made of a refractory material as a base material. The refractory material forming the intermediate dummy body includes ceramics, concrete, silica stone and the like, and a ceramic sintered body is preferable in consideration of heat resistance, strength, hardness and the like. The ceramics sintered body can be appropriately selected from oxide series, carbide series, and nitride series, for example, alumina sintered body, zirconia sintered body, magnesia sintered body, among which strength, thermal shock resistance, Alumina sintered body is preferable in consideration of high temperature stability and price. The shape of the intermediate dummy body may be any shape as long as it has a through hole through which the heat-resistant cord is inserted, and may be, for example, a cylindrical shape, a rectangular tube shape, or a spherical shape. It should be noted that a taper portion and a rounded portion for preventing cord-like damage can be formed at the opening portion of the through hole of the intermediate dummy body.

The leading dummy body is joined to the tip end of the heat-resistant cord.
The connecting means can be appropriately selected according to need. For example, a means for stopping with a stopper, a means for engaging with a recess fitting, or a means for integrally molding the cord-shaped tip and the leading dummy body is adopted. You can At least the tip of the leading dummy body is made of metal. The main reason is that when the end face of the rear end of the work is pushed by the leading dummy body, the heat of the rear end of the work is transferred to the leading dummy body. In this case, the entire lead dummy body can be made of metal, but only the tip portion may be made of metal. The metal is selected in consideration of heat resistance and heat transfer properties, and iron-based metals are typical, and among them, ordinary steel, cast steel, cast iron, and stainless steel can be adopted. The shape of the leading dummy body is appropriately selected as necessary, and may be a cylindrical shape, a round bar shape, a square tube shape, or a square bar shape.

In addition, the end of the cord on the side opposite to the leading dummy can be coupled to the winding drum. The winding drum can be installed on the inlet side of the induction heating device. In this case, after the heating is completed, the winding drum is rotated to wind the cord on the winding drum, whereby the leading dummy body and the intermediate dummy body fed into the induction heating device can be taken out from the induction heating device. You can easily.

[Operation] The rear end face of the last work is pushed by the front end face of the leading dummy body. At this time, the end surface of the rear end of the last work is in close contact with the end surface of the front end of the leading dummy body, and therefore the heat of the rear end of the last work is transferred to the metal portion on the leading dummy side. , The rear end of the last workpiece approaches a uniform temperature state.

[Embodiment] Hereinafter, a dummy tool of the present invention will be described with reference to a first embodiment shown in FIGS.

The dummy tool of the present embodiment has a suitable number of ceramic ropes 1 (heat-resistant temperature 1500 ° C.) as flexible heat-resistant ropes and through holes 20 having a circular cross section through which the ceramic ropes 1 are inserted. Intermediate dummy 2 and ceramic rope 1
And the leading dummy body 3 made of steel and joined to the tip of the.

The ceramic rope 1 is made of yarn in which ceramic fibers are carded into a sliver and twisted. The ceramic fiber that is the base material of the ceramic rope 1 is an alumina-silica system in consideration of heat resistance, tensile strength, cost, and the like. Its composition is 45-60% by weight alumina and 40-55% by weight silica. The diameter of the ceramic rope 1 can be selected in consideration of heat resistance and tensile strength, and is about 18 mm. The bulk density of the ceramic rope 1 is 0.32 g / cm ² . The tensile strength before heating of the ceramic rope 1 is 60 to 80 kg / 25φ.

The intermediate dummy body 2 is formed of an alumina-silica-based sintered body as a refractory material. The shape of the intermediate dummy body 2 is a cylindrical shape. Through hole 20 formed in the intermediate dummy body 2
The system is about 20 mm.

The leading dummy body 3 is detachably coupled to the tip of the ceramic rope 1. A stopper is used as the coupling means. The other end of the ceramic rope 1 is connected to the winding drum 4 by a stopper.

Next, the induction heating device 6 using the dummy tool of the present embodiment will be described with reference to FIG. The induction heating device 6 is
An appropriate number of induction heating furnaces arranged in series and containing an induction coil
60, a pinch roller 61 installed on the inlet 60a side of the induction heating furnace 60, a transfer conveyor device 62 installed on the inlet 60a side of the induction heating furnace 60, and a winding drum installation table 63. . The induction heating device 6 is connected to a high frequency generator (not shown).

When heating the work W, a high frequency current (1 KHz) is applied to the induction heating furnace 60 of the induction heating device 6 as in the conventional case.
The work W is conveyed to the pinch roller 61 side by the drive of the conveyer conveyor device 62 in a state where the work W is flowed, and the work W is sequentially bitten into the pinch roller 61, whereby the work W is sequentially conveyed to the induction heating device 6. Supply from the inlet 60a into the induction heating furnace 60. Then, as shown in FIG. 2, the work W slides on the skid rail 60c of the induction heating furnace 60. Then, as in the conventional case, the end surface of the rear end of each work W has a rear work W.
Since it is pushed by the end face of the front end of the work W, the end faces of the adjacent works W come into close contact with each other. Therefore, the magnetic flux concentration on the end face of the work W is eliminated, the heat transfer between the end faces of the work W, etc.
Overheating of the end face of is suppressed as much as possible.

The work sent to the induction heating furnace 60 of the induction heating device 6 is induction-heated to a high temperature of about 1000 to 1200 ° C. The work W having a high temperature is discharged from the outlet 60b of the induction heating furnace 60. The discharged work W reaches a forging press device by meeting a chute (not shown), and is forged into a wasteland by a wasteland forging die attached to the forging press device to become a wasteland forged product,
After that, the waste forged product is finish-forged by a finish forging die to be a finish forged product, and the finish forged product is deburred by a deburring die.

By the way, when the last work W is bitten by the pinch roller 61 and sent into the induction heating furnace 60 of the induction heating device 6, after the last work W is bited by the pinch roller 61, the winding drum installation table The leading dummy body 3 of the dummy tool installed at 63 is engaged with the pinch roller 61, and thereby the leading dummy body 3 is supplied into the induction heating furnace 60. Further, the intermediate dummy body 2 is engaged with the pinch roller 61, and the induction heating furnace 60
And the end face of the front end of the first dummy body 2 is pushed by the end face of the front end of the first intermediate dummy body 2. Similarly, the end face of the front end of the front dummy body 3 is pushed after the last work W. Push the end face of the end. In this way, the intermediate dummy bodies 2 are sequentially heated in the induction heating furnace.
By being supplied into the 60, the final work W is discharged from the outlet 60b of the induction heating furnace 60.

As described above, when pushing the end face of the rear end of the last work W with the end face of the front end of the leading dummy body 3,
Since the end face of the rear end portion and the end face of the front end portion of the leading dummy body 3 are in close contact with each other, the concentration of magnetic flux on the end face of the last work W can be eliminated, and the heat of the end face of the rear end portion of the last work W can be eliminated. Is transferred to the metal part of the leading dummy body 3, so that overheating of the end surface of the rear end of the last work W is suppressed as much as possible.

Since the intermediate dummy body 2 sent into the induction heating furnace 60 of the induction heating device 6 is a ceramic sintered body, and therefore no induction current is generated in the intermediate dummy body 2, the intermediate dummy body 2 is not induction-heated.

Now, as described above, the last work W is the induction heating device 6
When it is discharged from the outlet 60b of the induction heating furnace 60, the heating work of all the works W is completed, so that the rotation of the pinch roller 61 is stopped. At this time, the leading dummy body 3 and the intermediate dummy body 2 remain in the induction heating furnace 60 of the induction heating device 6. Therefore, with the pinch roller 61 removed from the predetermined position, the winding drum 4 installed on the winding drum installation base 63 is rotated in the rewinding direction manually or by driving a drive motor. Then, the ceramics rope 1 is drawn to the winding drum 4 and wound up, so that the leading dummy body 3 coupled to the ceramics rope 1 is drawn to the winding drum 4 side. Further, the end face of the rear end portion of the leading dummy body 3 is
Since the end face of the front end portion of the intermediate dummy body 2 adjacent to is pushed,
Similarly, the intermediate dummy body 2 is also drawn to the winding drum 4 side, and the other remaining intermediate dummy bodies 2 are also drawn to the winding drum 4 side. The dummy body 3 and the intermediate dummy body 2 are drawn out from the inlet 60a of the induction heating furnace 60.

(Effects of Embodiment) In this embodiment, since the induction current is not substantially generated in the intermediate dummy body 2 made of refractory material sent into the induction heating furnace 60 of the induction heating device 6, the intermediate dummy body 2 is No induction heating,
Therefore, the problem of waste of power consumption can be improved as compared with the conventional case using a dummy rod made of stainless steel.

Further, in this embodiment, even if the length of the entire dummy tool is increased, the length of each of the leading dummy body 3 and each intermediate dummy body 2 is short, and the leading dummy body 3 and the intermediate dummy body 2 are also short. Boundary between the intermediate dummy body 2 and the intermediate dummy body 2 adjacent to
Since the boundary between and can be easily bent, the problem of bending of the dummy pusher due to thermal deformation is solved. Furthermore, since the boundary between the leading dummy body 3 and the intermediate dummy body 2 and the boundary between the adjacent intermediate dummy bodies 2 and the intermediate dummy body 2 can be easily bent, the dummy tool is installed despite its long length. Space can be reduced. Moreover, since the individual lengths of the leading dummy body 3 and the intermediate dummy body 2 are short, the intermediate dummy body 2 and the leading dummy body 3 can be wound around the winding drum 4, which not only requires a small installation space, It is also convenient to carry.

In addition, in this embodiment, when the ceramic rope 1 and the leading dummy body 3 are damaged, the ceramic rope 1 and the leading dummy body 3 can be detached from each other, so that the ceramic rope 1 and the leading dummy body 3 are replaced with new ones. can do. Of course, even if the intermediate dummy body 2 is damaged, if the leading dummy body 3 is removed from the ceramic rope 1, the intermediate dummy body 2 inserted in the ceramic rope 1 can also be removed from the ceramic rope 1. The intermediate dummy body 2 can also be replaced with a new one.

Further, in the present embodiment, when the intermediate dummy body 2 is inserted in the induction heating furnace 60, the intermediate dummy body 2 covers the ceramic rope 1, so that the ceramic rope 1 is radiated into the induction heating furnace 60. It is possible to protect the ceramic rope 1 from the above and is therefore advantageous in extending the life of the ceramic rope 1.

[Other Embodiments] FIG. 4 shows a second embodiment of the present invention. In this case, the structure is basically the same as that of the above-described embodiment. Therefore, also in the second embodiment, basically, the same operational effect as that of the first embodiment described above is obtained. However, the winding drum 4
The intermediate dummy body 2 is engaged with the rear end portion of the ceramic rope 1 by a retaining device 22 in a retaining state. Also in this case, the ceramic rope 1 can be manually pulled in and the leading dummy body 3 and the intermediate dummy body 2 in the induction heating furnace 60 can be taken out from the inlet 60a of the induction heating furnace 60.

A third embodiment of the present invention is shown in FIGS. 5 and 6. In this case, the structure is basically the same as that of the above-described embodiment. Therefore, also in the third embodiment, the same operational effect as the first embodiment described above is basically obtained. However, the outer surfaces of the leading dummy body 7 and the intermediate dummy body 8 are square in cross section. The intermediate dummy 8 is formed with a through hole 80 having a circular cross section for inserting the ceramic rope 1. This dummy tool is mainly applied to an induction heating furnace 71 having a work insertion passage 70 having a rectangular cross section, and
The work is guided in a skid rail 72 arranged in the work insertion path 70 and conveyed in the induction heating furnace 71.

Although the ceramic rope 1 is used in the above-mentioned embodiment, the strength is not limited to this, and the strength may be increased by blending a steel wire or the like with the ceramic rope 1 depending on the heating temperature.

[Advantageous effects of the invention] According to the dummy tool for the induction heating device of the present invention, the induction heating has improved the problem of power consumption, the problem of bending due to thermal deformation, and the problem of overheating of the end surface of the rear part of the work. A device dummy pusher can be provided.

[Brief description of drawings]

1 to 3 show a first embodiment of the present invention, and FIG. 1 is a perspective view of the entire dummy pusher. FIG. 2 is a cross-sectional view of a state where a work is being conveyed in the induction heating furnace of the induction heating device, and FIG. 3 is a side view of the induction heating device. FIG. 4 shows a second embodiment of the present invention and is a perspective view of the entire dummy pusher. 5 and 6 show a third embodiment of the present invention, and FIG. 5 is a perspective view of the entire dummy pusher, and FIG.
The figure is a cross-sectional view of a state in which a work is conveyed in an induction heating furnace of an induction heating device. In the figure, 1 is a ceramic rope (cord), 2 is an intermediate dummy body, 20 is a through hole, 3 is a leading dummy body, 4 is a winding drum, and 6 is an induction heating device.

Claims (1)

[Scope of utility model registration request] 1. A heat-resistant cord (1) which is to be inserted into a passage of an induction heating device through which a work passes and which is made of ceramic and has flexibility.
And at least two intermediate dummy bodies (2) having a through hole (20) in which the heat-resistant cord is inserted and having a refractory material as a base material.
And a lead dummy body (3) made of metal, at least the tip portion of which is connected to the tip portion of the heat-resistant cord, and a dummy pusher for an induction heating device.