JPS6310465Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an unbalance detector attached to a centrifugal dryer.

In general, the structure of a centrifugal dryer is such that the processing material is distributed and balanced, and the processing tank is supported by anti-vibration rubber in order to prevent vibrations from being transmitted to other parts as much as possible during operation.

Therefore, unless an unforeseen situation occurs, all vibrations generated during operation are absorbed by the vibration isolating rubber and do not cause any particular problems.

However, for example, if silicon wafers used in the manufacture of semiconductors are stored in several carriers and processed in a centrifugal dryer, damaged items may get mixed up or the wrong quantity may be used. The weight of the stored items may become unbalanced due to unexpected reasons such as this, and in such cases, the load distribution becomes unbalanced and abnormal vibrations occur during operation.

If you continue to operate the machine under abnormal vibrations, the stored items will shake and move violently, which may not only cause damage, but also pose a risk of causing damage to the equipment.
If abnormal vibrations are found to occur, it is necessary to immediately stop operation.

Particularly with automated dryers, since there may be no workers nearby, it is desirable to be able to automatically deal with abnormalities when they occur.

The present invention takes such a situation into account, and automatically detects when an imbalance occurs and provides information for stopping the operation of the device.

In other words, a light source and a photoelectric element such as a photovoltaic cell that receives the light are placed facing each other across a detection plate with a small hole that allows light to pass, which is provided in a part that does not vibrate during normal operating conditions. During normal operation, light passes through the system, but when abnormal vibrations occur, a detection plate moves horizontally to prevent light from passing through.When the light is blocked, a controller is activated to automatically turn off the power. .

Next, the present invention will be explained with reference to the drawings.

Fig. 1 is a cross-sectional view showing the structure of the embodiment, and Fig. 2 is a partially enlarged perspective view, in which 1 is a processing tank of the centrifugal dryer main body, and 2 is a turntable provided inside the processing tank 1. , 3 is a carrier holding stand fixed at a suitable position on the inner circumference of the turntable 2, 4 is a connecting shaft that transmits rotation to the turntable 2, 5 is a vibration-proof rubber, 6
7 is a frame body that holds the processing tank 1 via the vibration isolating rubber 5; 7 is a rotation drive unit that transmits the rotation of the connecting shaft 4 to rotate the turntable 2;
9 is a detection plate provided protruding from an appropriate position on the bottom surface of the rotary drive unit 7; 9 and 9' are photoelectric switches disposed with the detection plate 8 sandwiched therebetween; 9 is a light projection unit having a light source; 9' 10 is a mounting seat for the photoelectric switches 9 and 9' fixed to the frame 6; 11 is a light passage hole provided in the detection plate 8; 12 is the light receiving section. This is a small hole for light reception provided in the portion 9'.

Now, when the rotary drive unit 7 (the inside is not shown) is driven and rotational motion is transmitted to the connecting shaft 4 extended through the space provided at the bottom of the processing tank 1,
The turntable 2 rotates. In this case, if the weight of the wafers stored in the carrier (not shown) held on the carrier holding stand is in a balanced state, the turntable 2 will rotate smoothly without lateral vibration, and the anti-vibration rubber 5 will Therefore, longitudinal vibrations are completely absorbed.

Therefore, since the processing tank 1 does not vibrate, the light from the light projecting section 9 passing through the passage hole 11 of the detection plate 8 and the small hole 12 of the light receiving section 9' is unhindered and reaches the light receiving section. Reach 9'. In the illustrated example, the detection plate 8 is provided on the rotary drive unit 7, but the location is not limited to this, and it is of course possible to select a location that does not vibrate during normal operation, or on the outer wall of the processing tank 1.

If there is an imbalance in the stored items, only vibrations in the vertical direction will be absorbed by the vibration isolating rubber 5, but the treatment tank 1 will be moved in any horizontal direction due to the influence of abnormal vibrations. , the passage hole 11
The light passing through the small hole 12 is blocked, and the amount of light received by the light receiving section 9' decreases.

Therefore, when the amount of received light changes, if the amount of change is used as a parameter to drive a control circuit (not shown) and shut off the power supply circuit that drives the rotary drive section 7, then if abnormal vibration occurs, Since the system automatically stops operation, it is possible to prevent failures from occurring.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view showing the structure of the embodiment. FIG. 2 is a partially enlarged perspective view. 1...processing tank, 2...turntable, 3...
Holding stand, 4... Connection shaft, 5... Anti-vibration rubber, 6...
Frame body, 7...Rotation drive unit, 8...Detection plate, 9,
9'...Photoelectric switch, 10...Mounting seat, 11...
...passing hole, 12...small hole.

Claims (1)

[Scope of utility model registration request] A processing tank of the main body of the centrifugal dryer is fixed to the frame via anti-vibration rubber at appropriate positions around the processing tank, and a turntable on which the processed material is placed is provided inside the processing tank. It has a structure formed to be rotationally driven, and is fixedly arranged with a detection plate having a light transmission hole provided in a part that does not vibrate under normal operating conditions, and the detection plate sandwiched therebetween. A centrifugal dryer equipped with an unbalance detector, characterized in that it is equipped with a photoelectric switch for detecting unbalance.