JP3615242B2 - Turntable drive mechanism for heat treatment equipment - Google Patents

Description

[0001]
[Industrial application fields]
The present invention relates to a turntable drive mechanism for rotating a turntable of a heat treatment apparatus, and more particularly to a turntable drive mechanism provided with a means for preventing unwanted materials from flowing into a gap between a drive shaft and a bearing.
[0002]
[Prior art]
In addition to a drive source such as a motor, the drive mechanism for the turntable requires a drive shaft that transmits rotational torque generated by the drive source to the turntable in the heating chamber, and a bearing that fixes the drive shaft. The A minute gap is provided between the drive shaft and the bearing to enable rotation of the drive shaft, but this gap may cause the following problems.
[0003]
[Problems to be solved by the invention]
Generally, in the heating chamber of the heat treatment apparatus, heating and cooling are repeated by the heat treatment, so that pressure fluctuation occurs in the heating chamber and in the bearing. This pressure fluctuation is generated in the gap between the drive shaft and the bearing. This causes a respiratory effect, and therefore, there is a risk that contaminants generated during cooking flow into the gap. Further, when the inside of the heating chamber is washed with a detergent or the like, the same fear is caused by the detergent surfactant or the like. Furthermore, since the gap between the drive shaft and the bearing is fine, a capillary phenomenon may occur. This phenomenon also causes the same fear. Conventionally, no particularly effective measures have been taken against this problem, and therefore, there has been a problem that the smooth rotation of the drive shaft is hindered by contaminants or the like that have entered these gaps.
Therefore, the present invention provides a device that effectively prevents unwanted materials from flowing between the drive shaft and the bearing.
[0004]
[Means for Solving the Problems]
The present invention relates to a turntable driving mechanism for rotationally driving a turntable disposed inside a heating chamber of a heat treatment apparatus by a drive source disposed outside the heating chamber. In this driving mechanism, the turntable is arranged below the heating chamber, the drive source is arranged on top of the heating chamber, the heating so as to transmit to the turntable rotational torque from a drive source through a heating chamber of the upper plate A drive shaft extending between the upper and lower portions of the chamber, a bearing for fixing the drive shaft so as to rotate relative to the upper plate , and located between the drive shaft and the bearing at the upper portion of the heating chamber air introducing means for generating an air flow towards the interior downwardly from the outside of the heating chamber through the fine gaps to allow rotation of the drive shaft that is included.
The air introduction means includes an air introduction port provided on the outer periphery of the bearing side wall outside the heating chamber, and an air introduction tube connected to the air introduction port.
Hereinafter, the present invention will be described with reference to the accompanying drawings.
[0005]
【Example】
For easy understanding, FIG. 1 shows only the turntable according to the present invention and the drive system for this turntable among the components of the heat treatment apparatus.
A motor 1 that is a drive source is provided outside the heating chamber above the heating chamber. Since the turntable 9 is provided in the heating chamber, the connecting shafts 3, 5, etc. are used to transmit the rotational torque generated by the motor to the turntable 9. The rotational torque generated by the motor 1 is transmitted to the spiral miter gear 11 through the connecting shaft 3 and further transmitted to the connecting shaft 5 through the spiral miter gear 13 meshed therewith. The connection shaft joint 15 provided between the connection shaft 3 and the motor 1 is provided to release the engagement between the connection shaft 5 and the motor 1 and is compressed when an overload is applied to the turntable 9. The function of the coil spring is to release the strass load applied to the connecting shafts 3, 5 and the like. A turntable drive gear 7 is provided at the end of the connecting shaft 5 and meshed with the teeth of the turntable 9 to rotate the turntable 9.
[0006]
In order to hold the connecting shaft 5 in a predetermined position, a bearing 40 is fixedly provided on the upper plate 22 of the heating chamber. The upper plate 22 has a through hole through which the connecting shaft 5 passes. The connecting shaft 5 is rotatably held by a bearing 40 between the outside and inside of the heating chamber through the through hole. An enlarged view of the bearing 40 and the connecting shaft 5 is shown in FIG.
As apparent from FIG. 2, the connecting shaft 5 has an extension 52 at the top thereof. The spiral miter gear 13 is fixed to the protrusion 54 at the upper part of the connecting shaft 5, so that rotational torque can be transmitted between the connecting shaft 5 and the spiral miter gear 13. The connecting shaft 5 is received by a metal bearing 42 provided at the lower portion of the bearing 40 at the lower portion of the extended portion 52 and is held at a predetermined height. The lower side surface of the extended portion 52 is surrounded by a side wall 44 that is fixedly provided outside the metal bearing 42. There is no gap between the side wall 44 and the upper plate 22 of the heating chamber.
The upper portion of the extension portion 52 of the connecting shaft 5 is surrounded by the sleeve 45. A sealing member 41 is provided inside the upper end of the sleeve 45 so as to be in close contact with the connecting shaft 5 in a rotatable manner. A gap is provided between the portion other than the upper end portion of the sleeve 45 and the extended portion 52. A nut 43 fixed to the sleeve 45 is provided on the outer periphery of the sleeve 45. A support plate 6 that supports the connecting shaft 3 is extended to below the sleeve 45, and the nut 43 is fixed on the extension. There is no gap between the nut 43 and the support plate 6. The sleeve 45 is held in place by the nut 43.
[0007]
An air inlet 46 penetrating the nut 43 is provided, and air pressurized by a fan (not shown) is sent from the inlet 46 into the bearing through the hose 48. The fan may be provided only for this purpose, but may be used so as to share a fan used for cooling a part such as a magnetron. That is, since the flow rate of the air used for this purpose is very small, a part of the air generated by a fan provided for cooling a part such as a magnetron may be guided to the air inlet 46.
There is a relatively large gap between the bearing 40 and the extended portion 52 of the connecting shaft 5, and air introduced from the air introduction port 46 can easily enter the gap. The air introduced into the relatively large gap is further guided downward along the lower portion of the extension portion 52 and further along the side surface portion of the extension portion 52 and flows out into the heating chamber.
[0008]
【The invention's effect】
According to the configuration of the present invention, minute air can always flow out from the inside of the bearing 40 to the inside of the heating chamber through the gap between the connecting shaft 5 and the bearing 40. As a result, it is possible to effectively prevent contaminants and the like from flowing between the connecting shaft 5 and the bearing 40, and therefore, the occurrence of troubles in the rotation of the connecting shaft is reduced.
[Brief description of the drawings]
FIG. 1 is a view showing a heat treatment apparatus according to an embodiment of the present invention using only a drive system and a turntable.
FIG. 2 is an enlarged view of a bearing 20 and a connecting shaft 5 according to the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Motor 3 Connection shaft 5 Connection shaft 6 Support plate 7 Turntable drive gear 9 Turntable 11 Spiral miter gear 13 Spiral miter gear 15 Connection shaft joint 22 Upper plate 40 Bearing 41 Sealing member 42 Metal bearing 43 Nut 44 Side wall 45 Sleeve 46 Air Inlet 52 Expansion part 54 Projection part

Claims (2)

In a turntable drive mechanism for driving a turntable disposed inside the heating chamber of the heat treatment apparatus to rotate by a drive source disposed outside the heating chamber,
The turntable is disposed in the lower portion of the heating chamber, wherein the driving source is disposed in an upper portion of the heating chamber, so as to transmit rotational torque from the driving source to the turntable through the top plate of the heating chamber A driving shaft extending between an upper portion and a lower portion of the heating chamber, a bearing for fixing the driving shaft so as to be rotatable with respect to the upper plate , and a driving shaft disposed on the upper portion of the heating chamber. and an air introduction means for generating an air flow towards the interior downwardly from the outside of the heating chamber through the fine gaps to allow rotation of the drive shaft is present between the bearing A turntable drive mechanism characterized by that. 2. The turntable drive mechanism according to claim 1, wherein the air introduction unit includes an air introduction port provided on an outer periphery of the side wall of the bearing outside the heating chamber, and an air introduction pipe connected to the air introduction port.

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