JPH02159402A - Flow controller - Google Patents

Abstract

PURPOSE:To obtain a device of small type and high heat-proof and vibration- proof quality which has characteristics in its flow that the flow coefficient is large in the forward direction and small in the backward direction and accord ingly that it restrains the back flow by providing, inside a pipe, a flow route which gradually reduces its sectional area toward the downstream in forward direction of the flow of the fluid inside the pipe. CONSTITUTION:A nozzle 3 made of a funnel-shaped member is held in such a way as its flat plate part provided around its margin on the upstream in its forward direction A is sandwiched between a pair of flanges 2 of a pipe 1. As it has such flow characteristics that the flow coefficienct is large as the flow route is reduced in the forward direction by forming a smooth flow and it is small in the backward direction as the flow route is suddenly reduced, a great amount of flow flows at the normal time and the back flow is not completely restrained but there is an effect to keep the back flow minimal when the back flow is caused due to the decrease of pressure on the upstream. Additionally, it is possible to set it even at a part of high temperature or at a point of strong vibration as it has no mechanical system, and also it is pos sible to set it where there is not enough space as its size is compact.

Description

[Detailed description of the invention] [Industrial application field] TECHNICAL FIELD The present invention relates to a metering device for flow in a fluid passageway.

[Conventional technology]

FIG. 3 shows a cross-sectional view of a conventional tvI quadmeter.

In the figure, 1 is a tube, 2 is a seven flange, and 11 is an orifice held between a pair of flanges 2. A indicates the forward direction of the flow of fluid within the pipe. The orifice 11 has a hole in the center of a flat plate with a diameter smaller than the inner diameter of the tube 1, and has the same flow coefficient whether the flow is in the forward direction or in the reverse direction, so it has no backflow suppressing function. For this reason, if it is necessary to suppress backflow, it is necessary to provide a separate check pulp device.

FIG. 4 shows a sectional view of a conventional check valve. In the figure, 1 is a pipe, 2 is a flange, 12 is a main body of a check valve mounted between a pair of 7 flanges 2, and 13
is the valve body of the same check valve, and arrow A is the forward direction of the flow of fluid in the pipe. In this device, when the flow is in the forward direction,
Since the valve body opens and closes when the flow is in the opposite direction, backflow is completely inhibited.

Conventionally, the flow rate Xt device and the backflow suppressor have been separate devices, and no device has been found that integrates both functions.

[Problem to be solved by the invention]

Recently, in various equipment systems, safety design including failure analysis has become mainstream. Among these, what is required of a flow rate meter for a fluid passage is to suppress backflow when the upstream passage is damaged and backflow occurs. However, the table shows that because the conventional Oriice has a vertically symmetrical shape, the flow coefficients in the one-mile direction and the reverse direction are the same, and there is no effect of suppressing backflow, resulting in a large backflow flow rate and secondary damage to the equipment system. was likely to cause it. Therefore, it was necessary to provide a backflow suppressor separately from the flow Jl meter. Check valves and the like have been used for this purpose. Check valves and the like cannot be used in places with high temperatures or strong vibrations, and because they are relatively large, they cannot be installed in places with limited space. Furthermore, these orifices and check valves have a relatively large pressure loss, so by setting the maximum pressure of the equipment system high, the pressure-resistant structure of the equipment is increased, resulting in increased weight, increased cost, and decreased energy efficiency. Ta.

The present invention has a backflow suppression function integrally, is small in size,
The present invention aims to provide a flow rate meter that is heat and vibration resistant.

[Ninth means to solve the problem]

The present invention has solved the above-mentioned problem, and is characterized in that a member is provided inside the pipe to form a flow path whose cross-sectional area gradually decreases toward the downstream in the forward direction of the flow of fluid in the pipe. This relates to a flow rate meter.

[Effect]

In the flow rate meter of the present invention, the cross-sectional area of the flow path is gradually reduced toward the downstream in the forward direction, so that the flow rate characteristic has a large flow coefficient in the forward direction and a small flow coefficient in the reverse direction.
Therefore, backflow can be suppressed. Furthermore, since it does not have any moving parts, it is possible to provide a device that is small and has high heat and vibration resistance.

A cross-sectional view is shown. In the figure, arrow A is the forward direction of the flow of the fluid in the pipe, 1 is the pipe, 2 is the nozzle consisting of 7 flanges, and 3 #i^9 dowel-shaped members, and the cross-sectional area of the flow path gradually increases toward the downstream direction. Reduction 7B (~, a fluid passage of a small cross-section tank is formed in the downstream part of the above member in the forward direction. This member is held by sandwiching the flat plate part provided at the edge of the upstream part in the forward direction between a pair of flanges 2. There is.

In the flow rate meter of this embodiment, in the forward direction, the flow path is reduced after forming a smooth flow, so the flow rate coefficient is large, and in the reverse direction, the flow path is suddenly reduced, and the flow is Because it collides with the flow path and becomes turbulent, it has a flow characteristic of a small flow coefficient, so a large flow flows during normal (forward flow), but when the upstream flow path is damaged and reverse flow occurs due to a drop in upstream pressure, this suppress.

Although the flow titrator of this embodiment cannot completely prevent backflow, it has the effect of minimizing the flow rate of backflow. In addition, since it does not include mechanical mechanisms such as moving parts, it can be installed in high-temperature areas or areas with strong vibrations, and its compact size allows it to be installed easily even in places where space is limited. , same [7(a) A-arrow diagram is shown.

In the figure, arrow A is the forward direction of the flow of the fluid in the pipe, 1 is the pipe, 2 is the 7-lunge, and 4 is the annular nozzle wall consisting of a hemispherical member. An annular nozzle is formed which gradually contracts in the forward downstream direction, and an annular fluid passage 5 having a small cross-sectional area is formed in the forward downstream part of the member. 2) are four support legs provided at the forward downstream part of the annular nozzle wall 4,
Its outer end is fixed to a flat plate portion sandwiched between a pair of flanges 2, and holds the annular nozzle wall.

The flow rate meter of this embodiment also has a large flow rate coefficient in the forward direction because the flow path shrinks after forming a smooth flow, and in the reverse direction, the flow path suddenly contracts and the flow flows into the member. Because it collides and becomes turbulent, it has a flow characteristic of a small flow coefficient.
During normal flow (forward flow), a large violet flows, and when the upstream side passage is damaged and reverse BFC occurs due to a drop in upstream pressure, this is suppressed. Furthermore, since the machine does not include any moving parts or mechanisms, it can be installed in high-temperature areas or areas where vibration is reduced.
Due to its compact size, it can be installed even in places where space is limited.

As described above in the embodiments, with this device,
Until now, due to environmental factors such as temperature and vibration, or lack of space, it has not been possible to install a mechanical backflow prevention mechanism such as a check valve, and a This makes it possible to dramatically improve the safety of equipment systems.
In addition, since the pressure loss of this flow rate meter during forward flow is small, the maximum pressure of the device system can be set low, and the pressure-resistant structure of the device can be simplified, reducing weight and cost. , energy efficiency improvements, etc. are expected. can.

〔Effect of the invention〕

The fluid body of the present invention, the sewing hot water a, is equipped with a member forming a flow path whose cross-sectional area gradually decreases in the direction downstream of the flow of in-tube bookbinding, in the interior of 'd. It is possible to provide a flow meter that has a backflow suppressing function, is small, and has heat and vibration resistance.

[Brief explanation of the drawing]

Figure 1 is a sectional view of one embodiment of the present invention, Figure j'R2 (a)
t is a cross-sectional view of another embodiment of the present invention, FIG. FIG. 1... Pipe, 2... 7 langes, 3... Nozzle made of a funnel-shaped member, 4... Annular nozzle wall made of a hemispherical member, 5... Annular fluid passage, 6... Support Leg, 11... Oriwiss, 12... Check valve body, 13... Valve body of check valve.

Claims (1)

[Claims] 1. A flow rate meter comprising a member forming a flow path whose cross-sectional area gradually decreases in the forward direction downstream of the flow of fluid in the pipe, inside the pipe.