JPS6233585A - Air Shower Room Limiting Device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] Industrial Application Field The present invention purifies the air in the clean room by limiting the number of people entering the air shower room that functions as the front room of the clean room where semiconductor manufacturing equipment is installed. This relates to a device that limits the number of people entering an air shower room.

2. Description of the Related Art Conventionally, this type of device for restricting the number of people entering an air shower room has a configuration as shown in FIGS. A signal is generated in response to increase the count value of the pulse counter 3. The comparison means 4 then compares the count value with the fixed set value, and if the count value exceeds the value, the warning means 6 warns the person entering the room, and the locking means 7 attached to the clean room side door 6 prevents entry into the clean room. was prevented. The warning is issued by pulse counter 3.
In the figure, 8 indicates the air shower room, 9 indicates the air outlet, and 10 indicates the grating.

Problems to be Solved by the Invention However, with this configuration, the limit switch 2 is activated simply by opening and closing the general room side door 1, and the intended purpose such as issuing a warning or locking the clean room side s6 is not achieved. The present invention was made in view of these problems, and it is possible to control the number of people entering the room with a simple configuration. To provide a device that can accurately grasp the number of occupants and also easily change the setting of the capacity and perform corresponding operations. Two non-contact object detectors installed side by side, and the
a detection order determining means that receives detection signals from the two non-contact object detectors; and a pulse counter that receives one of the detection signals from the two non-contact object detectors. , comprising a room occupant capacity setting means, a comparison means for comparing the count value of the pulse counter and a value set by the room occupant capacity setting means, and an output means for outputting a comparison result by the comparison means, The apparatus for limiting the number of occupants in an air shower room is configured such that the output signal of the detection order determining means is inputted as an up/down switching signal of the pulse counter.

According to the above-described configuration, the present invention determines whether a person has entered the room or left the room using the two non-contact object detectors and the detection order determining means input from these, and uses the pulse counter to determine whether the person has entered the room or left the room. It is possible to hold the value of the number of people currently entering the room, set the value of the number of people by the number of people entering the room by the number of people entering the room, and accurately output the status of whether the number of people is over the number of people by the comparison means and the output means.

Embodiment FIG. 1 is a block diagram showing an embodiment of the apparatus for restricting the number of persons entering an air shower room according to the present invention, and FIG. 2 is a signal waveform diagram thereof. In FIGS. 1 and 2, reference numeral 11 denotes a door on the side of the general room, which allows a person entering the room to enter the air shower room 12 by opening this door. The air coming out of the air outlet 13 in the air shower room 12 is sucked into the grating 14 as shown by the arrow, and during this time, dust adhering to the clothes of the occupants is removed. Note that 15 in the figure is a clean room side door leading to the clean room.

Two non-contact type object detectors 16a are provided in a portion of the air shower room 12 near the general room side door 11.

16b is provided, and its output signal is sent to the detection order determining means 1.
7, the non-contact object detector 16a detects it first when the object is in the direction of entering the room, and the non-contact object detector 16b detects it first when the object is in the direction of leaving the room. . Then, the detection order determining means 17 increases the output signal when the non-contact object detectors 16a, 16b detect it in the direction of entering the room, and increases the output signal when the non-contact object detectors 16a, 16b detects it in the direction of exiting the room. The output is turned down. The signal of either the non-contact type object detector 18a or 16b is pulsed color/reactor 18.
The pulse counter 1B is counted up or down, and the switching signal for counting up or down is obtained from the output signal of the detection order determining means 17. Reference numeral 19 denotes a room capacity setting means, and in this explanation, a case where the capacity is set to two people is shown. The comparison means 2o compares the count value of the pulse counter 18 with the value set by the room occupant capacity setting means 19, and the result is outputted to the output means 21 to determine whether or not the capacity is exceeded. Transmission to etc. can be carried out by any method such as sound or light.

If the capacity is exceeded, the count value will automatically count down when one person leaves the room, so the device can be used continuously without having to be reset.

The non-contact object detectors 16a and 16b can be of a light reflection type, a light transmission type, an ultrasonic reflection type, a pyroelectric type, etc. based on the operating principle, but any type may be used. Effects of the Invention As is clear from the description of the embodiments above, according to the present invention, the number of people entering the room can be reliably grasped with an extremely simple configuration, and the capacity setting can be changed. The corresponding operation is also easy and is extremely useful in practice.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing a device for limiting the number of people entering an air shower room according to an embodiment of the present invention, FIG. 2 is a signal waveform diagram of the same, and FIG. 3 is a block diagram showing a conventional device for limiting the number of people entering an air shower room. 4 are the same signal waveform diagrams. -15a, 16b...Non-contact object detector, 1
7...Detection order determination means, 18...Pulse counter, 19...Room occupant capacity setting means,
2o... Comparison means, 21... Output means. Name of agent: Patent attorney Toshio Nakao and one other person]

Claims (5)

[Claims] (1) Two non-contact type object detectors installed side by side in an air shower room, a detection order determination means for inputting detection signals from the two non-contact type object detectors, and a detection order determination means for inputting detection signals from the two non-contact type object detectors; a pulse counter that receives one of the detection signals from the type object detector as an input; a room occupant capacity setting means; a count value of the pulse counter and a set value by the room occupant capacity setting means; and an output means for outputting the comparison result of the comparison means, and the output signal of the detection order determination means is inputted as an up/down switching signal of the pulse counter. Number limiting device. (2) The device for restricting the number of people entering an air shower room according to claim 1, wherein the non-contact type object detector is a light reflection type non-contact type object detector. (3) The device for restricting the number of people entering an air shower room according to claim 1, wherein the non-contact type object detector is a light transmission type non-contact type object detector. (4) The device for restricting the number of persons entering an air shower room according to claim 1, wherein the non-contact type object detector is an ultrasonic reflection type non-contact type object detector. (5) The device for restricting the number of people entering an air shower room according to claim 1, wherein the non-contact object detector is a pyroelectric non-contact object detector.