JPH0144973B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a differential pressure damper that operates to keep indoor pressure constant, and in particular to a differential pressure damper that opens and closes ventilation holes in response to even the slightest pressure difference between indoors and outdoors. Regarding.

In clean rooms in factories that produce electronic parts, precision machinery parts, food, pharmaceuticals, etc., hospitals, etc., it is necessary to maintain indoor temperature and humidity conditions within a certain range for quality control and other purposes. Therefore, it is necessary to install a differential pressure damper that can quickly respond to minute fluctuations in indoor air pressure.

Conventional differential pressure dampers used for this purpose include those disclosed in Japanese Utility Model Publication No. 52-46060 and Japanese Utility Model Application Publication No. 52-8947. The former type opens and closes the ventilation hole by rotating a blade relative to the ventilation hole, and the latter opens and closes the ventilation hole using the elastic force of a spring. In either type, as the damper opens, the restoring force increases in proportion to the inclination angle of the blades or the degree of extension of the spring, so if the processing air volume increases, the blade opening degree becomes insufficient and the indoor static pressure ( The disadvantage is that the differential pressure) tends to increase without being constant, making it difficult to maintain a constant differential pressure. That is, there was a tendency for the indoor pressure to rise beyond a certain permissible value because it could not respond quickly to indoor pressure fluctuations, and the indoor temperature and humidity conditions could not be maintained within a certain range. In other words, it has been difficult to smoothly adjust changes in scenery to changes in indoor pressure.

The present invention was made in view of the above-mentioned conventional problems, and its purpose is to quickly open and close the damper opening in response to minute pressure fluctuations in the room, and to always control the indoor pressure at a constant level. The purpose of the present invention is to provide an improved differential pressure damper that can be used.

In order to achieve this objective, the present invention provides an outer casing 1
a seat plate 6 provided in an inclined manner so as to form an inclined opening 5 therein;
A guide shaft 3 whose base end is fixed to a supporting member 4 fixed nearby, passes through the inclined opening 5, and is inclined upward from the indoor side to the outdoor side with respect to the horizontal direction.
and a blade 7 whose center is slidably engaged with the guide shaft 3 and moves in the direction of the guide shaft 3, and the blade 7 is moved toward the inclined opening 5 with a constant return force due to its own weight. It consists of a differential pressure damper that is closed off.

Hereinafter, the present invention will be described with reference to the illustrated embodiment. In the figure, reference numeral 1 denotes an outer casing, which is mounted in a mounting hole provided in a wall 2 by a normal method. Reference numeral 3 denotes a guide shaft provided in the outer casing 1, and its base end is attached to the support member 4 so as to be inclined upward from the indoor side to the outdoor side with respect to the horizontal direction. The guide shaft 3 is supported by penetrating the center of an inclined opening 5 provided in the outer casing 1 at an angle, and its lower base end is directed toward the inside of the chamber, and its higher end is directed toward the outside of the chamber. It will be done. Reference numeral 6 denotes a seat plate having a circular inclined opening 5 formed therein, and is provided in the outer casing 1 in an inclined manner. The inclined opening 5 is provided at right angles to the guide shaft 3. A blade 7 is slidably engaged with the guide shaft 3 and moves in the direction of the guide shaft 3, and a balance weight 8 is attached to the center of the blade. Therefore, the blade 7 opens and closes the inclined opening 5 while moving forward and backward along the guide shaft 3 facing the inclined opening 5. The blade always closes the inclined opening 5 with a constant return force due to its own weight. 9 is a gasket attached to the periphery of the inclined opening 5; 10 is a bearing for the blade 7; 1
1 is a mounting tube for the bearing 10. Incidentally, the balance weight 8 is ring-shaped, and an appropriate number of balance weights 8 are attached to the mounting tube 11.

The differential pressure damper according to the invention is mounted on the wall 2 of the clean room as shown. Since the guide shaft 3 provided inside the outer casing 1 is inclined upward from the inside of the room to the outside of the room with respect to the horizontal, the blades 7 that are slidably engaged with this guide shaft 3 are able to absorb pressure inside and outside the room. When there is no difference, the inclined opening 5 is closed.
That is, due to its own weight, etc., the blade 7 tilts with a returning force that returns to the closing direction of the inclined opening with a constant moment force, regardless of the position on the axis corresponding to the inclination angle of the guide shaft 3. The opening is blocked. Therefore, when the indoor pressure is less than the pressure determined by the component force moment in the closing direction of the inclined opening due to the blade's own weight and the indoor pressure, the blade 7 When the balance weights 8 are attached in this manner, their weight causes them to descend along the guide shaft 3 and close the inclined opening 5 provided on a plane perpendicular to the axial direction of the guide shaft 3. However, when the pressure in the room increases beyond a predetermined set value, the blade 7 resists the force moment determined by the inclination angle of the inclined opening 5 and the weight of the blade 7 (including the weight of the balance weight 8). Push up to fully open the inclined opening 5. At this time, the blade 7 does not gradually move upward on the guide shaft 3 on the guide shaft 3 toward the outdoor side in proportion to the rise in indoor pressure, but rather the indoor pressure is greater than the component force moment due to the weight of the blade 7, etc. As soon as it wins, the guide shaft tilts upward and moves to the end of the shaft. Therefore, if there is a pressure fluctuation on the indoor side that exceeds the set value, the blades 7 immediately become fully open. Then, a ventilation gap is formed between the blade 7 and the inclined opening 5, and the pressurized air in the room is relieved through this gap. When the pressure in the room decreases to a predetermined set value or lower, the blade 7 descends again along the guide shaft 3 due to its own weight, and the inclined opening 5
This will result in occlusion. The opening/closing operation of the blade 7 by movement on this guide shaft is performed by the bearing 10 with extremely small frictional force, so it can quickly respond to pressure fluctuations in the room, move smoothly, and always maintain the indoor pressure constant. Can be done.

As explained above, according to the present invention, the damper is provided with a seat plate forming an inclined opening in the outer casing, and passing through the inclined opening and inclined upward from the indoor side to the outdoor side with respect to the horizontal direction. and a blade whose center is slidably engaged with the guide shaft and moves in the direction of the guide axis, and the blade moves the inclined opening with a constant return force due to its own weight. Since the structure is designed to close the opening, the blade's own weight closes the inclined opening in response to pressure fluctuations in the room, and if the set value is even slightly exceeded, the blade immediately opens fully to provide pressure relief. Therefore, it has the advantage of being able to quickly respond to changes in air volume, quickly opening and closing the damper opening in response to minute fluctuations in indoor pressure, and being able to control indoor pressure at a constant level at all times.

[Brief explanation of drawings]

1 is a partially cutaway front view of a differential pressure damper according to the present invention, FIG. 2 is a longitudinal sectional view thereof, and FIG. 3 is a detailed view of section A in FIG. 1. 1: Outer casing, 3: Guide shaft, 5: Inclined opening, 7:
Feather.

Claims (1)

[Claims] 1. A seat plate provided at an angle to form an inclined opening in the outer casing, and a base end fixed to a support member fixed in the outer casing near the seat plate and extending through the inclined opening. a guide shaft provided to be inclined upward from the indoor side to the outdoor side with respect to the horizontal direction, and a blade whose center slidably engages with the guide shaft and moves in the direction of the guide axis, A differential pressure damper in which the blade closes the inclined opening with a constant return force due to its own weight.