JP2007138252A - Inlet door of heat treatment chamber in vacuum carburizing furnace - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an inlet door of a heat treatment chamber in a vacuum carburizing furnace with a simple and inexpensive structure where only elevating/lowering means for the door is present as a driving means for the door, and the other driving means is not particularly required. <P>SOLUTION: The inlet door of a heat treatment chamber comprises: an intermediate plate 12 in which seal members 9, 9 are arranged at both the sides in such a manner that the opening part 6 at the front face of a cooling chamber 2 as a heat treatment chamber to be charged with a work 5; and two outside inlet door 1a and inside inlet door 1b sandwiching the intermediate plate 12 and arranged so as to be contacted with both the sides of the seal members 9, 9. The outside inlet door 1a and inside inlet door 1b are guided by direct-acting bearings 14, 14, and can be elevated/lowered individually. The intermediate plate 12 has a communication hole 23, and when the outside inlet door 1a and the inside inlet door 1b has descended and come to the state of shielding the inner circumferential space 24 of the intermediate plate is made, the inside of the inner circumferential space 24 of the intermediate plate is exhausted via the communication hole 23 of the intermediate plate 12, and the outside inlet door 1a and the inside inlet door 1b are pressed against the intermediate plate 12 by the atmospheric pressure at the outside of the cooling chamber and the internal pressure of the cooling chamber 2. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an entrance door of a heat treatment chamber of a vacuum carburizing furnace having an entrance door, a cooling chamber, and a heating chamber, and partitioning the cooling chamber and the heating chamber by an intermediate door.

Conventionally, heat treatment furnaces including a vacuum carburizing furnace include a vacuum processing type and a vacuum furnace that cools the atmosphere with nitrogen gas during cooling. In a vacuum carburizing furnace, it is necessary to seal the outside of the furnace and the inside of the furnace in order to exhaust the air in the furnace and reduce the pressure close to vacuum. For this reason, when the air in the furnace is exhausted, the entrance door that becomes the work entry port needs some means for sealing the door and the furnace body so that the air does not enter the furnace from outside the furnace. In order to maintain the internal pressure of the cooling chamber, a heat treatment furnace that cools the atmosphere requires means for pressing the cooling chamber door against the cooling chamber. As an entrance door of a heat treatment chamber of a vacuum carburizing furnace having an entrance door, a cooling chamber, and a heating chamber, and partitioning the cooling chamber and the heating chamber by an intermediate door, for example, those described in Patent Documents 1, 2, and 3 is there. Patent Document 1 describes an example of a pressure furnace and describes a method in which a door is clamped by a simple clamping device, and Patent Document 2 links a cylinder outside the furnace as a door clamp driving means in addition to a door raising / lowering driving means. The structure for pressing the door in the furnace against the surface to be sealed is described, and in Patent Document 3, a pressurizing chamber is provided so as to surround the door of the adjacent opening of the adjacent heat treatment furnace, and the upper and lower doors of the adjacent opening are formed. A door called a gate valve is installed in the pressurizing chamber, and a pressure difference is applied between the inside of the furnace and the pressurizing chamber to seal the inside of the furnace.
Public Utility Sho 63-32299 Utility Model Gazette No. 2556214 Japanese Patent Publication No. 8-26394

  However, in the thing of patent document 1, it is necessary to provide many clamping devices around the door, and it is necessary to clamp each manually or with a driving device, and the cost of the clamping device is high. It was more expensive to clamp with. The thing of patent document 2 requires the door clamp drive means in addition to the door ascending / descending drive means, and also requires a cylinder outside the furnace for pressing the door, a toggle clamp, a cam, etc. Requires a lot of space. In Patent Document 3, a pressurizing chamber is required in addition to the door ascending / descending drive means. Depending on the size of the door, an inert gas such as nitrogen is necessary in the pressurizing chamber, which is extremely expensive. And requires a lot of space. In Patent Documents 1, 2, and 3, all the devices are required in addition to the door ascending / descending driving means, and the cost of the clamping device is high.

  The subject of the present invention is that the door drive means is only the door up / down drive means, and no other drive means is required, and the entrance door of the heat treatment chamber of the vacuum carburizing furnace has a simple and inexpensive structure. Is to provide.

For this reason, the present invention has an inlet door, a cooling chamber and a heating chamber, and the cooling chamber which is a heat treatment chamber into which a workpiece enters in an inlet door of a heat treatment chamber of a vacuum carburizing furnace in which the cooling chamber and the heating chamber are partitioned by an intermediate door. An intermediate plate that is fixed to the cooling chamber furnace body so as to close the opening on the front surface and that has sealing members disposed on both sides at positions corresponding to the periphery of the opening, and sandwiches the intermediate plate and contacts both surfaces of the sealing member Two outer entrance doors and an inner entrance door arranged in a possible manner, the outer entrance door and the inner entrance door being guided by linear motion bearings arranged on both sides of the intermediate plate, and the outer entrance door And the inner entrance door can be individually raised and lowered by independent driving means supported by the cooling chamber,
The intermediate plate has a communication hole that opens from the outer peripheral edge of the intermediate plate to the inner peripheral edge of the intermediate plate,
When the outer inlet door and the inner inlet door are lowered to shield the intermediate plate inner space, the intermediate plate inner space is exhausted through the communication hole of the intermediate plate, and the outside of the cooling chamber Solving the above-mentioned problems by providing an inlet door of a heat treatment chamber of a vacuum carburizing furnace, wherein the outer inlet door and the inner inlet door are pressed against the intermediate plate by atmospheric pressure and the internal pressure of the cooling chamber. did.

In the present invention, an intermediate plate that is fixed to the cooling chamber furnace body so as to close the opening on the front surface of the cooling chamber, which is a heat treatment chamber into which a workpiece enters, and has sealing members disposed on both sides at positions corresponding to the periphery of the opening. Two outer entrance doors and an inner entrance door disposed so as to sandwich the intermediate plate and be in contact with both surfaces of the sealing member, and the outer entrance door and the inner entrance door are disposed on both surfaces of the intermediate plate. Each of the outer entrance door and the inner entrance door is individually raised and lowered by independent driving means supported by the cooling chamber.
The intermediate plate has a communication hole that opens from the outer peripheral edge of the intermediate plate to the inner peripheral edge of the intermediate plate,
When the outer inlet door and the inner inlet door are lowered to shield the intermediate plate inner space, the intermediate plate inner space is exhausted through the communication hole of the intermediate plate, and the outside of the cooling chamber Since the outer inlet door and the inner inlet door are pressed against the intermediate plate by the atmospheric pressure and the internal pressure of the cooling chamber, the door drive means is only the door up / down drive means, and the other drive means are A simple and inexpensive structure that is not particularly necessary is provided for the entrance door of the heat treatment chamber of the vacuum carburizing furnace.

  Preferably, the linear motion bearing is disposed with a gap with respect to both surfaces of the intermediate plate by the mounting member of the linear motion bearing, and in the inner peripheral space of the intermediate plate by a spring built in the mounting member of the linear motion bearing. When the air is not exhausted, it is slightly lifted from both surfaces of the intermediate plate, and eliminates rubbing with the seal members disposed on both surfaces of the intermediate plate when the outer entrance door and the inner entrance door are raised and lowered.

  An example of the best mode for carrying out the present invention will be described with reference to FIGS. FIG. 1 is a schematic side cross-sectional view of an inlet door of a vacuum carburizing furnace according to an embodiment of the present invention, a cooling chamber as a heat treatment chamber, a heating chamber, and an intermediate door, and FIG. 2 is a schematic plan cross-sectional view taken along line AA of FIG. 3A is a left side view of FIG. 1, a front view of a cooling chamber and an entrance door as a heat treatment chamber, FIG. 4A is an enlarged cross-sectional view of a main part of FIG. 3, and FIG. FIG. 5A is a right side view of the outer entrance door and the inner entrance door, and shows details of the drive mechanism for raising and lowering the outer entrance door and the inner entrance door, and the intermediate plate, the opening, and the communication hole. FIG. Is a partially enlarged cross section of the fixture of the linear motion bearing in the vicinity of the BB line, (b) is a partially enlarged cross section along the BB line in (a) (same as the BB line in FIG. 4A). (C) is a state in which the outer entrance door and the inner entrance door are lifted from both sides of the intermediate plate with a slight clearance by the spring built in the linear bearing fixture from the state (b). Indicate the that state.

  The inlet door of the heat treatment chamber of the vacuum carburizing furnace according to the embodiment of the present invention includes an inlet door 1, a cooling chamber 2, and a heating chamber 3, and the vacuum carburizing furnace in which the cooling chamber 2 and the heating chamber 3 are partitioned by an intermediate door 4. In the entrance door 1, the seal members 9 and 9 are fixed at positions corresponding to the periphery of the opening 6 and fixed to the cooling chamber furnace body so as to close the opening 6 on the front surface of the cooling chamber 2, which is a heat treatment chamber into which the workpiece 5 enters. 4 (b)) is disposed on both sides of the intermediate plate 12, and the two outer entrance doors 1a and 1b are disposed so as to sandwich the intermediate plate 12 and be in contact with both surfaces of the seal members 9 and 9. The outer entrance door 1a and the inner entrance door 1b are guided by linear motion bearings 14 and 14 disposed on both surfaces of the intermediate plate 12 and are cylinders 15 and 16 which are independent driving means supported by the cooling chamber 2, respectively. Thus, the cylinder rods 17 and 18 and the link devices 19 and 20 can be individually raised and lowered. The intermediate plate 12 has a communication hole 23 that opens from the outer peripheral edge 21 of the intermediate plate to the inner peripheral edge 22 of the intermediate plate, and the outer inlet door 1a and the inner inlet door 1b are lowered to shield the inner peripheral space 24 of the intermediate plate. When this happens, the inner space 24 of the intermediate plate 12 is exhausted through the communication hole 23 of the intermediate plate 12, and the outer inlet door 1a and the inner inlet door 1b are connected to the intermediate plate by the atmospheric pressure outside the cooling chamber and the internal pressure inside the cooling chamber 2. It is intended to be pressed against 12. That is, the atmospheric pressure outside the cooling chamber is about 100 KPa, the internal pressure inside the cooling chamber 2 is about 80 KPa, and the vacuum pressure in the inner circumferential space 24 of the intermediate plate is exhausted to about 1 Pa. Due to the atmospheric pressure, the inner entrance door 1 b is pressed against the intermediate plate 12 with an extremely strong force due to the internal pressure in the cooling chamber 2. The cylinder rod 18 of the cylinder 16 for driving the inner entrance door 1b protrudes into the cooling chamber 2 and is connected to the link device 20, and the intermediate plate 12 has an upper end 51 and a lower end 52 (FIG. 4B) in the cooling chamber 2. Each is supported and fixed to the furnace wall 50 of the cooling chamber 2.

In the cooling chamber 2, there are an in-furnace transfer device 27 and an elevating device 28 for immersing the work 5 in an oil tank 29 (FIG. 1). Between the cooling chamber 2 and the heating chamber 3, there is an intermediate door 4 that moves up and down by driving an endless chain 30 that vacuum seals the heating chamber 3. A heat insulating material 32 supported by a heat insulating frame (not shown) is arranged in the heating chamber 3, the rear portion of the heating chamber is blocked from the outside by a flange 33, and the heat insulating material 32 supported by the heat insulating frame can be taken out by removing the flange 33. it can. The outer inlet door 1a and the inner inlet door 1b are guided by four linear motion bearings 14 in FIGS.
The linear motion bearings 14 and 14 are arranged with clearances 25 and 25 on both surfaces of the intermediate plate 12 by the fixtures 13 of the linear motion bearings 14 and 14, and springs 26 and 26 built in the fixture 13 of the linear motion bearings 14 and 14. Thus, when the inside of the intermediate plate inner circumferential space 24 is not exhausted, the seal member 9 is arranged so as to be slightly lifted from both surfaces of the intermediate plate 12 and disposed on both surfaces of the intermediate plate 12 when the outer entrance door and the inner entrance door are raised and lowered. The friction with 9 was eliminated. FIG. 5C shows a state in which the entrance door is lifted from the intermediate plate with a slight clearance by the springs 26 and 26.

In the present invention, an intermediate plate that is fixed to the cooling chamber furnace body so as to close the opening on the front surface of the cooling chamber, which is a heat treatment chamber into which a workpiece enters, and has sealing members disposed on both sides at positions corresponding to the periphery of the opening. An intermediate plate in which the seal member is disposed on both sides at the periphery of the opening; and two outer entrance doors and an inner entrance door that are disposed so as to sandwich the intermediate plate and be in contact with both surfaces of the seal member. The outer entrance door and the inner entrance door are guided by linear motion bearings disposed on both sides of the intermediate plate, and the outer entrance door and the inner entrance door are individually provided by independent driving means supported by the cooling chamber. Can be raised and lowered,
The intermediate plate has a communication hole that opens from the outer peripheral edge of the intermediate plate to the inner peripheral edge of the intermediate plate,
When the outer inlet door and the inner inlet door are lowered to shield the intermediate plate inner space, the intermediate plate inner space is exhausted through the communication hole of the intermediate plate, and the outside of the cooling chamber Since the outer inlet door and the inner inlet door are pressed against the intermediate plate by the atmospheric pressure and the internal pressure of the cooling chamber, the door drive means is only the door up / down drive means, and the other drive means are A simple and inexpensive structure that is not particularly necessary is provided for the entrance door of the heat treatment chamber of the vacuum carburizing furnace.

  Preferably, the linear motion bearing is disposed with a gap with respect to both surfaces of the intermediate plate by the mounting member of the linear motion bearing, and exhausted in the inner circumferential space of the intermediate plate by a spring built in the mounting device of the linear motion bearing. When not, it was made to float slightly above both surfaces of the intermediate plate, and when the outer entrance door and the inner entrance door were raised and lowered, friction with the sealing members disposed on both surfaces of the intermediate plate was eliminated. In addition, although the inlet door of the vacuum carburizing furnace of the embodiment of the present invention has been described as the inlet door of the cooling chamber, the present invention can also be applied to the inlet door of other heat treatment chambers including the loading chamber of the vacuum carburizing furnace, the heating chamber, The entrance door of the heat treatment chamber of the vacuum carburizing furnace of the present invention includes an entrance door of another heat treatment chamber including a carry-in chamber and a heating chamber of the vacuum carburizing furnace.

The schematic sectional side view of the entrance door of the vacuum carburizing furnace of embodiment of this invention, the cooling chamber which is a heat treatment chamber, a heating chamber, and an intermediate door. FIG. 2 is a schematic plan sectional view taken along line AA in FIG. 1. (A) is a left view of FIG. 1, and is a front view of a cooling chamber and an entrance door which are heat treatment chambers. 3A is an enlarged cross-sectional view of a main part of FIG. 3, and FIG. 3B is a right side view of FIG. 3A as viewed from the B direction. The detail of a part and a communicating hole is shown. (A) is a partially enlarged cross-section of a linear bearing fixture near line BB in (a), and (b) is a line BB in (a) (line BB in FIG. 4 (a)). (C) is a partially enlarged cross-section along (same), and the outer entrance door and the inner entrance door are lifted from the both sides of the intermediate plate with a slight clearance by the spring built in the linear bearing fixture from the state (b). Indicates the state.

Explanation of symbols

1: entrance door, 1a: outside entrance door, 1b: inside entrance door, 2: cooling chamber (heat treatment chamber), 3: heating chamber 4: intermediate door 5: workpiece, 6: opening, 9: seal member, 12: Intermediate plate
13: Linear motion bearing fixture, 14: Linear motion bearing, 15, 16: Cylinder (drive means)
21: outer peripheral edge of the intermediate plate, 22: inner peripheral edge of the intermediate plate, 23: communication hole, 24: inner peripheral space of the intermediate plate

Claims (2)

An entrance door of a heat treatment chamber of a vacuum carburizing furnace that has an entrance door, a cooling chamber, and a heating chamber, and the cooling chamber and the heating chamber are partitioned by an intermediate door. An intermediate plate which is fixed to the cooling chamber furnace body so as to be closed and has a sealing member disposed on both sides at a position corresponding to the periphery of the opening, and 2 which is disposed so as to be able to sandwich the intermediate plate and to be in contact with both surfaces of the sealing member A plurality of outer entrance doors and inner entrance doors, the outer entrance doors and the inner entrance doors being guided by linear motion bearings disposed on both sides of the intermediate plate, and the outer entrance doors and the inner entrance doors, respectively. It can be raised and lowered individually by independent driving means supported in the cooling chamber,
The intermediate plate has a communication hole that opens from the outer peripheral edge of the intermediate plate to the inner peripheral edge of the intermediate plate,
When the outer inlet door and the inner inlet door are lowered to shield the intermediate plate inner space, the intermediate plate inner space is exhausted through the communication hole of the intermediate plate, and the outside of the cooling chamber An inlet door of a heat treatment chamber of a vacuum carburizing furnace, wherein the outer inlet door and the inner inlet door are pressed against the intermediate plate by an atmospheric pressure and an internal pressure of the cooling chamber.   When the linear motion bearing is disposed with a gap with respect to both surfaces of the intermediate plate by the fixture of the linear motion bearing, and the inside of the inner peripheral space of the intermediate plate is not exhausted by a spring built in the fixture of the linear motion bearing. The entrance door of the heat treatment chamber of the vacuum carburizing furnace according to claim 1, wherein the entrance door is slightly lifted from both surfaces of the intermediate plate.

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