JPH07185284A - Variable flow rate two-dimensional ejector mixing device - Google Patents

Abstract

PURPOSE:To continuously and smoothly change the flow rate of mixed gas while keeping the passage area ratio of primary and secondary streams constant by a single ejector. CONSTITUTION:In an ejector of which the main body 10 is equipped with a space 20 having a mixing chamber 22 receiving the primary stream discharged from a nozzle and permitting a secondary stream to flow in and a difuser part 23 extending to the outlet of the main body, a movable wall 40 is formed and at least one surface 20U demarcating the space 20 is flat with respect to one direction but not flat in the direction crossing said direction and the movable wall is airtightly fitted in the space so as to be slidable in one direction to demarcate the other one surface of the space.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to an esector mixing device for mixing two types of fluids.

[0002]

2. Description of the Related Art As this type of gas mixing device, there is an ejector (venturi) mixer. This is a device that mixes a high-pressure fluid (primary flow) that passes through a nozzle with a low-pressure fluid (secondary flow) that is sucked by it. This mixing ratio is
If the discharge pressure of the primary flow and the source pressure of the secondary flow are the same, it is determined by the flow passage area ratio of the primary flow and the secondary flow. Further, the flow rate of the mixed gas is also determined by this flow path area.

An ejector of this type is disclosed in Japanese Unexamined Patent Publication No. Sho 50-
There is one disclosed in Japanese Patent No. 53950. In this conventional example, a movable nozzle is used, and by advancing and retracting the movable nozzle, the passage area of the primary flow on the diffuser section side is reduced /
At the same time, the passage area on the diffuser side of the secondary flow is narrowed / widened.

[0004]

Therefore, in the case of the above-mentioned Japanese Patent Laid-Open No. 50-53950, the flow passage area ratio cannot always be made constant. This will be described with reference to FIG.

In FIG. 8, 101 is a low pressure chamber formed in the main body 100, 102 is a diffuser portion formed in the main body 100, 200 is the movable nozzle, 300 is a pin, and the movable nozzle 200 is a high pressure fuel gas (not shown). It communicates with the room. Here, the moving length of the movable nozzle 200 is d
Assuming x, the increase amounts ds ₁ and ds ₂ of the flow passage areas of the primary flow and the secondary flow are as follows: ds ₁ = π (d ₁ -2l ₁ sin θ ₁ cos θ ₁ ) sin θ ₁ dx ... (1) ds ₂ = π (d ₂ + 2l ₂ sin θ ₂ cos θ ₂ ) sin θ ₂ dx (2), and even if it does not, ds ₁ = ds ₂ does not hold and the flow channel area ratio is not constant.

Further, there is a structure in which the flow rate of the mixed gas can be changed while keeping the mixing ratio constant, as disclosed in Japanese Patent Laid-Open No.
Although disclosed in Japanese Patent No. 56229, the one disclosed here arranges a plurality of ejectors in parallel and controls the ejector to be used according to the load, so that the mixed gas flow rate is controlled stepwise. In addition to the problem that there is no choice but to use, a plurality of ejectors are used, so that there is a problem that the entire physique is large and the cost is high.

The present invention has been made in order to solve this problem. With a single ejector, the flow rate of the mixed gas is continuously smoothed while keeping the flow passage area ratio of the primary flow and the secondary flow constant. An object of the present invention is to provide a variable flow rate two-dimensional ejector mixing device that can be changed.

[0008]

In order to achieve the above object, the present invention provides, in claim 1, a main body in which a primary flow is discharged through a nozzle and a secondary flow is introduced, and an outlet from the mixing chamber. An ejector having a cavity having a diffuser portion extending up to and including a movable wall, wherein at least one surface defining the cavity is flat in one direction but flat in a direction intersecting the direction. The movable wall is hermetically fitted in the void so as to be slidable in the one direction and defines the other face of the void.

According to a second aspect of the present invention, the movable wall is a linear slide type movable wall.

According to a third aspect of the present invention, the movable wall is a rotary movable wall and is arranged concentrically with the main body.

[0011]

In the present invention, since one wall that defines a space through which a fluid flows is a movable wall, the amount of mixed gas can be smoothly changed by moving the movable wall forward and backward.

When the movable wall advances and retracts, the flow passage areas of the primary flow and the secondary flow surely change in proportion. Therefore, even if the movable wall moves, the flow passage area ratio between the two is always constant. .

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

In FIG. 1, 10 is a main body. Body 1
As shown in FIG. 3, 0 is configured as a rectangular block body having an opening 10P on one side surface and having a U-shaped cross section. End surface 10R on the left end side in the figure of the main body 10
A high pressure fluid supply port (primary flow supply port) 11 is formed in
The lower surface 10D has a low-pressure fluid supply port (secondary flow supply port) 12
Are formed. Further, the mixed gas outlet 13 is opened on the end face 10L on the left end side in the figure of the main body 10.

A chamber 22 in which a low-pressure fluid supply port (secondary flow supply port) 12 is opened in the main body 10, and a diffuser that spreads vertically in the figure from the chamber 22 toward the mixed gas outlet 13 in the figure. A void space 20 including a portion 23 is formed. Further, the main body 10 has a high-pressure fluid supply passage 21 extending from the high-pressure fluid supply opening (primary flow supply opening) 11 to the chamber 22, and in this example, the nozzle body 30 is fitted into the high-pressure fluid supply passage 21. It is fixed, and the C-shaped tip of the nozzle 31 of the nozzle body 30 projects into the chamber 22 and
It is open to. The upper surfaces 20U and 20D of the void 20 are symmetrical and are non-flat in the longitudinal direction (the direction of fluid flow), but flat in the width direction.

One side surface of the void 20 is the opening 10P.

Reference numeral 40 designates a linear slide type block-shaped movable wall, and as shown in FIG.
And a lower surface 20D, each of which has an outer shape having an upper surface 40U and a lower surface 40D that are slidably fitted to each of
It is slidably inserted therein to hermetically close the opening 10P. Portion 40R of movable wall 40 inserted into chamber 22
A wedge groove portion 40G circumscribing the nozzle 31 is formed on the end surface of the. Reference numeral 41 is a seal member.

FIG. 3 shows a manual drive mechanism 50 for moving the movable wall 40 back and forth. In the figure, 51 is a casing of the drive mechanism 50, and in this example, the movable wall 4
Also serves as a guide for 0. 52 is a screw shaft, and the movable wall 40 is formed with a screw hole 55 into which the screw shaft 52 is screwed. Reference numeral 53 is a manual knob for the screw shaft 52, and 54 is a bearing for receiving the screw shaft 52. A slide shaft 56 guides the movable wall 40.

In this example, the high-pressure gas (primary flow) Q _H flowing from the high-pressure fluid supply port (primary flow supply port) 11 passes through the nozzle 31 and then, in the chamber 22, the low-pressure fluid supply port (secondary flow). low pressure gas flowing from the supply port) 12 (secondary flow) Q _L
The mixed gas is discharged from the mixed gas outlet 13 through the diffuser portion 23.

In this example, the flow rate of the mixed gas is continuously changed by moving the movable wall 40.

The flow passage areas of the primary flow Q _H and the secondary flow Q _L are changed by moving the movable wall 40, but the flow passage area ratio is not changed. That is, the mixing ratio of the primary stream Q _H and the secondary flow Q _L is a top of the cavity 20 20 U, determined by the two-dimensional shape of the 20D, it will not be affected by the position of the movable wall 40.

Therefore, the flow rate of the mixed gas can be changed while keeping the mixing ratio constant. 4 and 5 show
9 shows another embodiment of the present invention.

In this embodiment, the main body 10 has a semi-cylindrical portion 10A and an axial center O from one side edge of the semi-cylindrical portion 10A.
And a plate-shaped portion 10B extending to the position. Reference numeral 60 denotes a rotary slide type movable wall, which is arranged coaxially 61 with the main body 10. The inner peripheral surface of the semi-cylindrical portion 10A of the main body 10 has the same shape as the upper surface 20U of the void 20 in FIG.
The outer peripheral surface of the movable wall 40 is shaped to fit with the inner peripheral surface.

FIG. 6 shows a usage example of the ejector shown in FIG. 2, which is used to control the pressure in the buffer tank 80 at a constant level.

Reference numeral 70 is a high pressure gas tank, and 71 is a cylinder. As shown in FIG. 7, a cylinder rod 72 extending from a piston 73 of the cylinder 71 has a movable wall 40.
Is connected with. One chamber 71A partitioned by the piston 73 of the cylinder 71 communicates with the buffer tank 80, and the other chamber 71B is provided with a cylinder spring 74.

When the pressure in the buffer tank 80 is reduced, the piston 73 is displaced to the right in FIG. 6, the flow passage area in the ejector 10 is increased, and the flow rate Q of the mixed gas supplied into the buffer tank 80 is increased. Increased buffer tank 80
The pressure inside becomes high. Conversely, when the pressure in the buffer tank 80 rises, the piston 73 is displaced leftward in FIG. 6, the flow passage area in the ejector 10 is reduced, and the mixed gas flow rate Q supplied into the buffer tank 80 is reduced. As a result, the pressure in the buffer tank 80 becomes lower.

There is

In the example of FIG. 7, the ejector shown in FIG. 2 is used, but the ejector shown in FIGS. 4 and 5 can also be used by using a rotating mechanism such as a gear mechanism.

[0029]

As described above, according to the present invention, one wall that defines a space through which a fluid flows is a movable wall.
By moving the movable wall, the amount of mixed gas can be changed smoothly.

When the movable wall moves, the flow passage areas of the primary flow and the secondary flow change in proportion to each other. Therefore, even if the movable wall moves,
The flow channel area ratio of both is always constant.

Moreover, the above effects can be obtained by a single mixing device.
You can get it at the same time.

[Brief description of drawings]

FIG. 1 is a sectional perspective view showing an embodiment of the present invention.

FIG. 2 is a perspective view showing a movable wall in the above embodiment.

FIG. 3 is a sectional view showing a manual drive mechanism for a movable wall in the above embodiment.

FIG. 4 is a sectional perspective view showing another embodiment of the present invention.

FIG. 5 is a schematic side sectional view of the other embodiment.

FIG. 6 is a system diagram showing an example of use of the above embodiment.

FIG. 7 is a cross-sectional view showing a partial structure of the above usage example.

FIG. 8 is a schematic diagram for explaining a problem of a conventional mixing device.

[Explanation of symbols]

 10 main body 11 high pressure fluid supply port 12 low pressure fluid supply port 13 mixed gas outlet 20 void 20U upper surface 20D lower surface 21 high pressure fluid supply path 22 mixing chamber 23 diffuser section 30 nozzle body 31 nozzle 40 linear slide type movable wall 50 manual drive mechanism 60 Rotating slide type movable wall

Claims (3)

[Claims] 1. An ejector having a movable wall, wherein the main body has a cavity having a mixing chamber into which a primary flow is discharged through a nozzle and a secondary flow inflowing, and a diffuser portion extending from the mixing chamber to an outlet. At least one surface defining the void is flat in one direction but not flat in a direction intersecting the direction, and the movable wall has the one direction in the void; A variable flow rate two-dimensional ejector mixing device characterized in that it is slidably fitted in a slidable manner to define another surface of the void. 2. The variable flow two-dimensional ejector mixing device according to claim 1, wherein the movable wall is a linear slide type movable wall. 3. The variable flow two-dimensional ejector mixing device according to claim 1, wherein the movable wall is a rotary movable wall and is concentrically arranged with respect to the main body.