JPS60211164A - Rotation transmission-seal device for vacuum equipment - Google Patents

Abstract

PURPOSE:To prevent a vacuum leakage and an abnormal noise from occurring as well as to eliminate trouble and damage by burnout in a motor, by using a static cacuum seal as a seal in vacuum equipment including a vacuum pump. CONSTITUTION:Each of magnetic torque transmitting members 7 and 9 is installed in the tip of a rotor shaft 2 of a vacuum pump and the inner side of a cylindrical member 8 to be connected to an output shaft 1, and likewise a cylindrical vacuum seal member 10 is installed in the tip of a driven shaft 2, passing through a space between these magnetic torque transmitting members 7 and 9. With this constitution, since the output shaft 1 of a motor and the rotor shaft 2 of the vacuum pump are mechanically not connected, a leak of oil and a vacuum leakage or an abnormal noise are all no longer produced even in time of use for years. In addition, even if overload happens in the vacuum equipment, an overmuch load is in no case imposed on the motor and, what is more, trouble and damage by burnout in the motor is preventable from occurring.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a rotation transmission/sealing device in a vacuum device such as a vacuum pump, particularly a mechanical booster pump, which includes a mechanism for transmitting the rotational power of a motor to the vacuum device and a rotary shaft seal. be.

[Technical background of the invention and its problems]

Conventionally, vacuum pumps, particularly mechanical booster pumps, are generally configured to receive rotational power from a motor via a transmission mechanism such as a belt. The shaft that transmits the rotational power from the motor is vacuum-sealed between the atmosphere side and the vacuum side, and conventionally, an oil seal or a mechanical seal is used for this vacuum seal. However, when used for a long period of time, does the oil seal leak?
Mechanical seals have the disadvantage of causing air leaks, and mechanical seals can also cause abnormal noises due to the incorporation of dust, and like oil seals, they can also cause oil and vacuum leaks.

These seals therefore require periodic adjustment or replacement, and as these seals are relatively expensive, their maintenance can also be costly.

On the other hand, the conventional power transmission mechanism between the vacuum bonder and the motor uses mechanical means such as a belt as described above, and the motor directly receives the load of the vacuum pump. Therefore, if the load on the vacuum pump fluctuates and becomes larger than the torque of the motor, there is a risk of burnout of the motor.

[Summary of the invention]

SUMMARY OF THE INVENTION An object of the present invention is to provide a rotation transmission/sealing device for a vacuum device that eliminates the drawbacks of conventional rotary shaft seals and can compensate for fluctuations in the load of the vacuum device.

In order to achieve this object, the rotation transmission/sealing device for a vacuum device according to the present invention has the tip of the drive shaft on the motor side and the tip of the driven shaft on the vacuum device side facing each other along the circumferential surface, and magnetically A torque transmitting member is provided, and a cylindrical vacuum seal member is provided that passes between opposing surfaces of the two magnetic torque transmitting members and encloses the magnetic torque transmitting member provided at the tip of the driven shaft within the vacuum device. It is characterized by

In the present invention, at least one of the magnetic torque transmission members includes a magnet.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to the accompanying drawings.

1st. - The figure shows the main parts of one embodiment of the device according to the present invention, l is the rotary drive shaft of the motor (not shown), - is the rotor shaft of the vacuum pump, and these shafts 1. are arranged on the same axis. 3 is the vacuum pump Cushing,
A motor mounting plate S is fixed to this cushioning 3 via a sealing member tag.

A1 at the end of the rotor shaft of the vacuum pump. A cylindrical member 6 for supporting the inner magnet is fixed to the cylindrical member B, and as shown in Fig. It is installed. Further, a cylindrical member g for supporting an outer magnet is fixed to the tip of the output shaft l of the motor, and this cylindrical member g is positioned so as to face the magnet 7 on the outer periphery of the cylindrical portion 6. , and a large number of magnets having the same shape as the magnet 7 are attached to the inner circumferential surface of the magnet 7. A suitable gap is provided between the end faces. A cylindrical seal member IO is inserted into this gap, and its end edge/(7a) is fixed to the side of the seal part. It is made of non-magnetic material to prevent loss and heat generation, and is constructed to withstand pressure of 1 atm.Also, the distance between the opposing inner and outer magnets, 9, can transmit the required torque. However, the relative axial positions of the inner and outer magnets can be finely adjusted by varying the distance between the vacuum pump and the motor, for example.

In the illustrated embodiment, the torque is transmitted by the mutual attraction between the inner and outer magnets 7.9, but if necessary, only one of these magnets 7.9 may be provided, and the other may be magnetic. It may be composed of members.

[Action of the invention]

Therefore, in the present invention, since the output shaft of the motor and the rotor shaft of the vacuum pump are not mechanically connected, vacuum and oil sealing can be performed statically. Since the parts are completely reduced, the drawbacks associated with conventional oil seals and mechanical seals can be substantially eliminated. In addition, even if a load larger than the torque of the motor is applied to the vacuum pump, it will only cause a slip in the magnetic torque transmission mechanism between the two shafts, so the motor will not burn out, and ζ etc. It also becomes possible to drive the mechanical booster pump from atmospheric pressure.

〔Effect of the invention〕

As explained above, according to the invention, a silent true seal is used in place of the conventional oil seal or mechanical seal, so even after long-term use, there will be no oil leaks, vacuum leaks, or abnormal noises. It does not occur and is extremely advantageous in terms of maintenance.

In addition, the output shaft of the motor and the driven shaft of the vacuum device are magnetically connected, so even if the vacuum device is overloaded, the motor will not be overloaded, reducing the risk of motor failure or burnout. stable operation can be guaranteed.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic vertical sectional view showing an embodiment of the present invention, and FIG. 1 is a different sectional view taken along arrows A and -A in FIG. In the figure, l: drive shaft, 2: driven shaft, 7.9: magnetic torque transmission member, 10: cylindrical vacuum seal portion side.

Claims (1)

[Claims] A magnetic torque transmitting member is provided at the tip of the drive shaft on the motor side and the tip of the driven shaft on the vacuum system side, facing each other along the curved surface, and a magnetic torque transmitting member is provided between the opposing surfaces of these two magnetic torque transmitting members. A rotation transmission/sealing device for a vacuum device, comprising a cylindrical vacuum seal member that encloses the magnetic torque transmission member provided at the tip of the driven shaft inside the vacuum device.