JPH04155178A - Muffle furnace - Google Patents

Abstract

PURPOSE:To prevent the breakage of a muffle due to the thermal deformation of the same effectively by a method wherein an opening and closing mechanism is provided with a supporting member, supporting a lid clamped to the muffle so as to be displaceable into up-and-down direction while following to the thermal deformation of the radial direction of the muffle, while the supporting member is provided displacably into the direction of the axial thermal deformation of the muffle while following to the radial thermal deformation of the muffle. CONSTITUTION:When heat treatment is applied, a muffle 3 becomes high temperature and the thermal deformation of the same is caused, however, the whole of an opening and closing device 20 is displaced so as to follow the axial thermal expansion of the muffle 3 whereby the thermal deformation in the direction will never be restrained. A lid 5, clamped to the muffle 3, is displaced upward by the radial thermal expansion of the muffle 3, however, the coil spring of a supporting member, supporting the lid 5, is elongated from compressed condition to an initial condition, the lid 5 is supported by the supporting member 32, the muffle 3 will never become the condition of a canti-lever and a load applied on a support 4a is not changed. When the temperature of the muffle is reduced after finishing the heat treatment and the muffle 3 is contracted axially and radially, the opening and closing device 20 is displaced to the side of the furnace body 1 while following to the shrinkage of the muffle 3 and the coil spring is contracted thereby displacing the lid 5 downward, however, the lid 5 is supported by the supporting member 32 at all times constantly.

Description

DETAILED DESCRIPTION OF THE INVENTION "Field of Industrial Application" The present invention relates to a heat treatment furnace, and particularly to a matzuru furnace in which a matzuru is provided in the furnace body.

"Conventional technology" An example of a conventional general Matsufuru furnace is shown in FIG.

In the figure, reference numeral 1 is a furnace body, 2 is a heat insulating material attached to the inner surface of the furnace body, 3 is a heat-resistant metal material placed horizontally in the furnace body l, 4i and 4b are supports for supporting the Matsofuru 3, 5 is a lid for opening and closing the opening at one end of the manifold 3; 6 is a heat insulating material attached to the inner surface of the lid 5; 7 is a furnace body l
8 is an exhaust pipe for evacuating the inside of the matsufuru 3, and 9 is an object to be processed stored in the manfuru 3. In such a Matsufuru furnace, after creating a vacuum inside the Matsufuru 3, atmospheric gas is introduced into the manfuru 3 as necessary, and the workpiece 9 is indirectly heated from outside the manfuru 3 by the heater 7 to perform various treatments. Heat treatment is performed.

The above-mentioned lid 5 is raised and lowered by an opening/closing mechanism that winds up a rope 10 to open and close the opening. A pair of furans formed on both sides; 1
1. Butt the 12 together and use the clamper 13 to close the lid 5.
is designed to be clamped against manful 3.

Further, a water cooling section 14 is provided around the opening of the matsufuru 3, and cooling water is passed through the water cooling section 14 so that the opening periphery is kept at a low temperature.

"Problem to be Solved by the Invention J" By the way, in the above-mentioned conventional Matsufuru furnace, the Matsufuru 3 reaches a high temperature during heat treatment and tends to expand thermally in both the axial direction and the radial direction, but the periphery of the opening is water-cooled. As the Matsufuru 3 is kept at a low temperature, it is thermally deformed into a so-called Trakuri shape as shown by the broken line in Fig. 5.When the Matsufuru 3 is thermally deformed into the Trakuri shape, 3 on the opening side sometimes rose above the support 4b.

In this case, an excessive load, that is, the entire weight of the Matsufuru 3 and the weight of the lid 5 clamped to it, will be applied to the other support 4a, and the Matsufuru 3 will be supported in a cantilevered state. An unreasonable force is applied to the part on the opening side of No. 3, and there is a temperature gradient in that part due to cooling by the water cooling part 14, causing a large thermal stress, so this part cannot recover. There was a risk that undesirable distortion would occur or damage would occur relatively early.

In order to prevent such distortion and breakage, efforts have been made to sufficiently increase the overall strength of the Matsufuru, but since the Matsufuru 3 is made of expensive heat-resistant metal, such measures would be costly in terms of equipment costs. This is undesirable because it causes an increase in the amount of water.

The present invention has been made in view of the above circumstances, and an object thereof is to provide a matsufuru furnace that can effectively prevent distortion and breakage of matsufuru due to thermal deformation.

Means for Solving the Problems J The present invention provides a Matsufuru furnace having a configuration in which a horizontally placed cylindrical Matsufuru is provided in the furnace body, which is clamped to an opening provided at one end of the muffle. The opening/closing mechanism is provided with a lid opening/closing mechanism that closes the opening, and the opening/closing mechanism includes a support member that supports the lid clamped to the Matsufuru so that it can be displaced in the vertical direction following the thermal deformation of the Matsufuru in the radial direction. The supporting member is provided so as to be freely displaceable in the axial direction following the thermal deformation of the matsufuru in that direction.

"Function" In the Matsufuru furnace of the present invention, the lid clamped to the Matsufuru moves in the vertical direction while always being supported by the support member, following the thermal deformation of the Matsufuru in the radial direction, and
Since the support member also displaces in that direction following the thermal deformation of the Matsufuru in the axial direction, it is possible to prevent excessive force from being applied due to the thermal deformation of the Matsufuru, and as a result, distortion and damage to the Matsufuru are prevented. occurrence is effectively prevented.

Embodiment Hereinafter, an embodiment of the present invention will be described with reference to FIG. 1, in which the same components as those of the conventional one shown in FIG. 4 are given the same reference numerals.

In the Matsufuru furnace of this embodiment, as in the conventional one, the seven flanges 11 and 12 formed on both the Matsufuru 3 and the lid 5 are butted against each other, and the lid 5 is clamped to the Matsufuru 3 by the clamper 13. The opening is closed with a button. Further, a water cooling structure using a similar water cooling section 14 is adopted around the opening of the matsufuru.

In addition, in the Matsufuru furnace of this example, Matsufuru 3
The connection position of the exhaust pipe 8 to the exhaust pipe 8 has been changed to the lower side compared to the conventional one, so that the vertical displacement of the exhaust pipe 8 when the Matsuful 3 is thermally deformed is reduced compared to the conventional one. However, this is not necessarily the case. In addition, the lid 5 in the conventional Matsufuru furnace has an outwardly convex shape, but the MS in this embodiment has a concave shape, thereby saving space on the front side of the furnace body 1. This may also be a convex shape like the conventional one.

In the Matsufuru furnace of this embodiment, an opening/closing mechanism 20 for opening and closing the lid 5 is provided on the front side of the furnace body 1.

The opening/closing mechanism 20 has wheels 21 attached to its base, and is operated by a hydraulic cylinder 22 in the direction of approaching and leaving the furnace body 1 (
An elevating frame 24 is movable in the left and right directions in FIG. 5 is installed.

The above-mentioned pole screw mechanism rotates the threaded rod 26 via the deceleration mechanism 25 by a motor (not shown).
A traveling nut 27 screwed onto the threaded rod 26
The lid 5 is raised and lowered by screw feeding, and the lid 5 is raised and lowered via the lifting frame 24 to which a traveling nut 27 is fixed. Threaded rod 26
and the reduction mechanism 25 are connected to each other by a spline shaft 28 that transmits rotational force but does not restrict the vertical movement of the threaded rod 26 relative to the transmission mechanism 25. It is possible to freely move up and down relative to the deceleration mechanism 25 within the range of the upper stopper 29 and lower stopper 30.

A support member 32 incorporating a coil spring 31 is attached to the base of the opening/closing mechanism 20, and when the lid 5 is lowered and set in the position where the opening is closed,
The lower surface of the elevating frame 24 contacts the upper end of the support member 32, so that the coil spring 31 is compressed.

That is, when the lid 5 closes the opening, the coil spring 31
is in a compressed state, so that the lid 5 is urged upward by the spring force of the fill spring 31 to close the opening. The amount of expansion and contraction of the coil spring 31 and the spring force are determined by considering the maximum amount of radial deformation of the Matsufuru 3 expected during processing, the weight of the lid 5, etc., and even when the Matsufuru 3 has undergone maximum thermal deformation. The setting is made so that a slight upward biasing force is secured.

To operate the Matsufuru furnace configured as described above, the lid 5 is raised to open the opening, and the workpiece 9 is loaded into the Matsufuru 3, and then the pole screw mechanism is activated to open the lid 5.
lower it to the level of the opening.

At this time, initially, the threaded rod 26 is lowered with respect to the transmission mechanism 25 due to the weight of the pole screw mechanism, and the upper stopper 29 is in contact with the transmission mechanism, but as the elevating frame 24 descends, After the lower surface contacts the upper end of the support member 32, the spring force of the coil spring 31 pushes up the threaded rod 26, and the lower stopper 30 moves to the transmission mechanism 25.
It will come into contact with. And in that state screw w26
is further rotated and the lifting frame 24 is further lowered against the spring force of the coil spring 31 to lower the lid 5 to the height of the opening, thereby compressing the coil spring 31 and releasing its spring force as described above. This causes the lid 5 to be biased upward. And the hydraulic cylinder 22
is operated to move the entire opening/closing device 20 toward the furnace body l side, bringing the seventh flange 12 of the lid 5 into close contact with the flange 11 of the Matsufuru 3, and the lid 5 is clamped to the Matsufuru 3 by the clamper 13.

After that, operate the pole screw mechanism in the opposite direction, and screw the screw rod 2.
6 is lowered relative to the transmission mechanism 25 to secure clearance between the lower stopper 30 and the deceleration mechanism 25, and the threaded rod 2
6 can be freely raised and lowered relative to the transmission mechanism 25. As described above, the lid 5 is supported in an upwardly biased state by the support member 31 via the elevating frame 24, and becomes free with respect to the pole screw mechanism.

Furthermore, the piston of the hydraulic cylinder 22 is set in a free state so that the entire opening/closing mechanism 20 can be freely displaced in the direction toward and away from the furnace body 1, and in this state, heat treatment is performed as usual.

As a result, the Matsufuru 3 reaches a high temperature and is thermally deformed into a trap shape as shown in FIG. Thermal deformation in that direction is not restricted. Further, due to the thermal expansion of the Matsufuru 3 in the radial direction, the lid 5 clamped to the Matsufuru 3 will be displaced upward, but in this case, the support member supporting the lid 5 will be displaced upward.
The second coil spring 31 stretches from the compressed state in an attempt to return to its original state, so the lid 5 remains supported by the support member 32 at all times. Therefore, the matsufuru 3 does not become cantilevered, and the load applied to the support 4a does not change. When the temperature of the Matsufuru 3 decreases after the treatment and the Matsufuru 3 contracts in the axial and radial directions, the opening/closing device 20 naturally displaces toward the furnace body 1 side, and the coil spring 31 Although the lid 5 is displaced downward as it contracts, the lid 5 remains supported by the support member 32 at all times.

As explained above, in the above-mentioned Matsufuru furnace, the lid 5 clamped to the Matsufuru 3 is supported by the support member 32 so as to be movable in the vertical direction following the thermal deformation of the Matsufuru 3 in the radial direction. In addition, since the opening/closing mechanism 20 of the lid 5 is made to be able to move freely following the thermal deformation of the Matsufuru 3 in the axial direction, the thermal deformation of the Matsufuru 3 during processing is not restricted, and the Matsufuru 3 There is no possibility that the material will be supported in a cantilevered state, and therefore, due to the temperature gradient that occurs during processing, there is no need to apply excessive force to parts that are particularly prone to distortion or damage. Therefore, the life of the matsuru 3 can be extended, and there is no need to increase the strength of the matsufuru more than necessary, so an increase in equipment costs can be avoided.

Note that the configuration of the opening/closing mechanism is not limited to the above embodiment, and may be modified as appropriate. For example, as shown in FIG. can be adopted. In this case, if the coil spring 31 cannot be sufficiently compressed simply by lowering the lid 5 by its own weight, a clamp 41 for compressing the coil spring 31 may be incorporated into the support member 32.

Further, the structure of the support member 32 may be changed appropriately, for example, instead of using the coil spring 31, a hydraulic clamp or an air V cylinder may be used, thereby supporting the lid 5 while being biased upward with a constant pressure. It can also be configured as follows.

Further, in the above embodiment, the entire opening/closing mechanism 20 is moved toward and away from the furnace body 1 by the hydraulic cylinder 22, but as shown in FIG. It may be configured so that they are brought into contact and separated. Third
The one shown in the figure employs a clamp as a support member 50 for supporting the lid 5, and this support member 50 is moved around the furnace body by a roller 52 that is guided by a guide member 51 and can be moved freely.
It is designed so that it can be freely engaged and dissociated from.

In addition, in the one shown in FIG. 3, the support member 50
The flange 11 of the Hamamatsuful 3 is supported, and the M5 is indirectly supported via the Matatsuful 3, but even in this case, there is no difference between directly supporting the lid 5 and M5. Exactly the same effect can be obtained.

"Effects of the Invention" As explained in detail above, the present invention is capable of supporting the lid clamped to the Matsufuru so that it can be displaced in the vertical direction by the support member following the thermal deformation of the Matsufuru in the radial direction. None, and the supporting member can be freely displaced by following the thermal deformation of the Matsufuru in the axial direction; therefore, the thermal deformation of the Matsufuru during processing is not restricted, and
Since the lid is always supported by the support member, the Matsufuru will not be left in a cantilevered state, and therefore, it will not be possible to apply excessive force to the parts that are particularly susceptible to distortion or damage. As a result, the lifespan of Matsufuru can be extended, and the strength of Matsufuru can be increased more than necessary. Since there is no need to set up tJ, an increase in equipment costs can be avoided.

[Brief explanation of the drawing]

FIG. 1 is a side view showing an embodiment of the Matsufuru furnace according to the present invention. 2 and 3 are partial side views showing other embodiments of the present invention. FIG. 4 is a side view showing a conventional Matsufuru furnace, and FIG. 5 is a diagram schematically showing the state of thermal deformation of Matsufuru in the conventional Matsufuru furnace. l...Furnace body, 3...Matsuful, 4s,
4b...Support, 5...Lid, 20.
...Opening/closing mechanism, 21...Wheel, 31...
... Coil spring, 32 ... Support member, 40
...Opening/closing mechanism, 50... Support member, 5
2... Laura. Applicant Ishikawajima Harima Heavy Industries Co., Ltd. Figure 3 Figure 2 Figure 4 Figure 5

Claims (1)

[Claims] A Matsufuru furnace having a configuration in which a horizontally placed cylindrical Matsufuru is provided in the furnace body is provided with a lid opening/closing mechanism that closes the opening by being clamped to an opening provided at one end of the Matsufuru, and the The opening/closing mechanism has a support member that supports the lid clamped to the Matsufuru in a vertically movable manner following the thermal deformation of the Matsufuru in the radial direction, and the support member is configured to move in the axial direction of the Matsufuru. A Matsufuru furnace is characterized in that it is disposed so as to be freely displaceable in the direction following the thermal deformation of the material.