JP2692938B2 - Flow control device - Google Patents

Description

The present invention relates to a flow rate adjusting device in a piping system in which fluid flows, and more particularly, to a constant flow rate ratio between fluids flowing in a plurality of pipes. The present invention relates to a flow rate control device that can be controlled.

(Prior Art) The necessity of controlling the flow rate ratio of fluids passing through different points of a piping system to be constant can be found in various industrial fields.

FIG. 8 shows a piping system for lubricating oil of a hydrostatic bearing. Here, the rotating shaft 1 is rotated inside the bearing housing 2 by hydraulic pressure. An oil pocket is provided on the inner peripheral surface of the bearing housing 2.
3a, 3b, 3c, 3d are provided, and each oil pocket 3a, 3b, 3c,
3d is connected to the lubricating oil pump 6 via the pipes 4a, 5a, 4b, 5b, 4c, 5c, 4d, 5d, and the lubricating oil from the oil sump 7 is supplied.

By the way, in order to prevent the contact between the rotating shaft 1 and the bearing housing 2 and the seizure, it is necessary to make the intervals between them uniform.
For that purpose, it is necessary to equalize the amount of oil pumped to the oil pockets 3a, 3b, 3c, 3d.

Therefore, conventionally, as shown in FIG. 8, each pipe 4a, 5a, 4
Constant flow valves 8a, 8b, 8c, 8d between b, 5b, 4c, 5c, 4d, 5d
I am trying to intervene.

As shown in FIG. 9, the constant flow valves 8a, 8b, 8c, 8d automatically adjust the position of the movable valve 12 by the spring 9 and the diaphragm 10 and always set the flow rate to a predetermined value automatically. Is.

That is, if the pressure P ₁ increases or the pressure P ₃ decreases,
The flow rate Q becomes large and the flow velocity passing through the contracted flow path a increases,
Differential pressure (P ₂ -P ₃₎ is increased. Thus, the movable valve 12 is moved upward diaphragm 10 and below the differential pressure (P ₂ -P ₃₎ is increased, the flow rate Q is decreased. When the pressures P ₁ and P ₃ change in the opposite manner to the above, the movable valve 12 is lowered by the pressure of the spring 9 and the flow rate Q is increased.

Here, the effective area of the diaphragm 10 is S, the movable valve
Assuming that the weight of the fluid 12 is W and the downward force of the spring 9 is F, (P ₂ −P ₃ ) × S = W + F (1) To establish. If you transform this, Therefore, the pressure difference before and after the contracting portion a is always kept constant, and a constant flow rate according to the opening degree of the throttle mechanism 13 is obtained.

By using the constant flow rate valves 8a, 8b, 8c, 8d having the above configuration, the amount of oil pumped to each oil pocket 3a, 3b, 3c, 3d becomes uniform, but the flow rate ratio is kept constant. The flow rate cannot be changed with.

FIG. 10 shows an example in a chemical plant, in which a raw material A in a storage tank 15a and a raw material B in a storage tank 15b are pumped in a reactor 14 via pipes 16a, 17a, 16b, 17b, respectively.
It is designed to be transported using 8a and 18b, and each pump
Flow rate adjusting devices 13a and 13b are installed on the discharge sides of 18a and 18b.

In such a plant, the feed rates of the raw materials A and B are increased or decreased in order to control the chemical reaction, but in this case, the mutual flow rate ratio may have to be kept constant. However, if constant flow valves are used for the flow rate adjusting devices 19a and 19b, it becomes difficult to perform such control.

(Problems to be Solved by the Invention) As described above, the constant flow valve can control the flow rate to a predetermined value, but cannot be used for control such as increasing or decreasing the flow rate while keeping the flow rate ratio constant. Further, since the flow resistance of the valve is adjusted in order to keep the flow rate constant, the flow resistance is increased by installing a constant flow valve in the piping system, which is not preferable.

The present invention has been made in view of the current situation, and an object of the present invention is to provide a flow rate adjusting device capable of increasing and decreasing the flow rate while keeping the flow rate ratio constant and reducing the flow resistance.

[Configuration of the invention]

(Means for Solving the Problems) As a means for achieving the above object, the present invention connects a plurality of positive displacement fluid machines each having an independent suction port and discharge port through an interlocking mechanism, The machine and the interlocking mechanism are characterized in that they are not powered from the outside.

Further, in the present invention, it is more preferable to provide the interlocking mechanism with an acceleration / deceleration mechanism and a clutch mechanism that is disengaged when the transmission torque exceeds a set value.

(Operation) In the flow rate adjusting device according to the present invention, a plurality of positive displacement fluid machines are connected via the interlocking mechanism. The positive displacement fluid machine also functions as a water turbine (motor) if energy is given from the fluid. Therefore, if this is connected via the interlocking mechanism, the flow rate ratio will be constant even if the temporary flow rate changes,
Moreover, when the flow rate of the predetermined fluid increases and the rotational speed of the positive displacement fluid machine increases, other positive displacement fluid machines act as pumps, and a part of the energy is returned to the fluid. Therefore, the energy consumption of the entire flow rate adjusting device is small.

Hereinafter, the present invention will be described with reference to the drawings.

First, the principle of the flow rate adjusting device according to the present invention will be described with reference to FIG.

In FIG. 1, reference numerals 20a and 20b are roots type positive displacement fluid machines, and both positive displacement fluid machines 20a and 20b are connected to mutually different pipes 21a, 22a, 21b and 22b, and are the same. Are connected by a rotary shaft 23.

Roots-type positive displacement fluid machines 20a and 20b have a structure in which a pair of eyebrow-shaped rotors 25 in a body 24 are incorporated as shown in FIG. ). If the rotational speed is N and the flow rate is Q, the rotational speed N and the flow rate Q are proportional to each other as shown in the following equation.

Q = k · N (3) Here, k is a proportional constant and represents the flow rate per rotation.

In the above configuration, both positive displacement fluid machines 20a, 20b,
Since the rotary shaft 23 is common, both positive displacement fluid machines 20a, 20b
Have the same rotation speed, and as a result, the flow rate is also the same according to the equation (3). This relationship has two positive displacement fluid mechanisms.
This holds true as long as 20a and 20b are connected by the same rotary shaft 23, and the flow rate ratio of the fluid passing through is constant even if the flow rate changes.

That is, when the flow rates of the fluids flowing through the two piping systems 21a, 22a, 21b, 22b are the same, the two positive displacement fluid machines 20a,
As shown in FIG. 3 (a), 20b acts as a water turbine that is supplied with energy from a fluid and rotates. Since the power generated at this time only corresponds to the friction torque of the rotary shaft 23, the pressure drop amounts ΔH ₁ and ΔH ₂ between the inlet and the outlet of the positive displacement fluid machine 20a, 20b are almost zero, and the flow resistance is Is extremely small.

On the other hand, if the fluid on one of the piping systems 21a, 22a easily flows for some reason and the flow rate increases, the positive displacement fluid machine 20
The rotation speed of a increases. However, since the rotary shaft 23 is common, the rotational speed of the positive displacement fluid machine 20b of the other piping system 21b, 22b also increases, and the flow rate ratio of the two piping systems 21a, 22a, 21b, 22b does not change. At this time, the positive displacement fluid machine 20a acts as a water wheel that drives the positive displacement fluid machine 20b, and conversely, the positive displacement fluid machine 20b acts as a pump that is driven by the positive displacement fluid machine 20a. As a result, the pressure in the piping system is
As shown in Fig. (B), in one piping system 21a, 22a, a large pressure drop ΔH ₁ occurs from the inlet to the outlet of the positive displacement fluid machine 20a, but in the other piping system 21b, 22b, a positive displacement fluid is generated. On the contrary, the pressure rises from the inlet to the outlet of the machine 20b. For this reason, fluid energy is consumed in the positive displacement fluid machine 20a, but a part of the energy consumed there is returned to the fluid again by the positive displacement fluid machine 20b, and therefore the energy of the entire piping system is reduced. Consumption is low.
This is a major feature of the flow rate adjusting device according to the present invention,
This is a difference of the constant flow valve that becomes flow resistance and consumes energy of the fluid to keep the flow rate constant.

FIG. 4 shows the first embodiment of the present invention, in which the flow rate adjusting device is applied to a hydrostatic bearing.

That is, in FIG. 4, reference numeral 1 is a rotary shaft,
The rotary shaft 1 is adapted to rotate inside the bearing housing 2 by hydraulic pressure. Oil pockets 3a, 3b, 3c, 3d are provided on the inner peripheral surface of the bearing housing 2,
Each of these oil pockets 3a, 3b, 3c, 3d has pipes 4a, 5a, 4b, 5
The lubricating oil pump 6 is connected via b, 4c, 5c, 4d and 5d,
The lubricating oil from the oil stagnation 7 is supplied.

Between the pipes 4a, 5a, 4b, 5b, 4c, 5c, 4d, 5d, as shown in FIG. 4, four positive displacement fluid machines 30a, 30b, 30c,
30d are provided respectively, and these positive displacement fluid machines 30a, 30b, 30c, 30d are connected by the same rotary shaft 31.

 Next, the operation of the present embodiment will be described.

The lubricating oil from the lubricating oil pump 6 is supplied to the pipes 4a, 5a, 4b, 5
b, 4c, 5c, 4d, 5d through oil pockets 3a, 3b, 3c,
It will be supplied to 3d, but each pipe 4a, 5a, 4b, 5b, 4
Since the positive displacement fluid machines 30a, 30b, 30c, 30d connected by the rotary shaft 31 are provided between c, 5c, 4d, 5d, respectively, even if the head of the lubricating oil pump 6 changes, Although the absolute value of the flow rate changes, the flow rate ratio supplied to each oil pocket 3a, 3b, 3c, 3d becomes the same. Therefore, even if the discharge amount of the lubricating oil pump 6 is changed according to the load of the bearing, the amount of oil supplied to each oil pocket 3a, 3b, 3c, 3d becomes uniform, and the rotating shaft 1 and the bearing housing 2 The distance between and can always be kept uniform.

FIG. 5 shows a second embodiment of the present invention, in which the positive displacement fluid machines 40a, 40b, 40c having different flow rates per rotation are arranged between the pipes 41a, 42a, 41b, 42b, 41c, 42c. In addition, the positive displacement fluid machines 40a, 40b, 40c are connected by the same rotation line 43, and the fluid is sent to the pipes 41a, 41b, 41c by pumps 44a, 44b, 44c having different discharge amounts. It is the one that was paid.

Above in the configuration, each pump 44a, 44b, the flow rate of the fluid Q _a to transport at 44c, Q _b, When a Q _c, to the conditions in the pump or piping is slightly changed, the pipes 41a, 42a, 41b, 4
The flow rate ratio of the fluids flowing through 2b, 41c, 42c does not change from the flow rate ratio per revolution of each positive displacement fluid machine 40a, 40b, 40c, and the fluid is always transported at the same flow rate ratio.

FIG. 6 shows a third embodiment of the present invention, in which three positive displacement fluid machines 50a, 50b, 50c are connected by the same rotary shaft 51 and three positive displacement fluid mechanisms 50a, 50b are connected. , 50c, two connecting devices 52a, 52b are arranged respectively.

In the above configuration, when the coupling devices 52a, 52b are acceleration / deceleration devices, the ratio of the rotational speed of each positive displacement fluid machine 50a, 50b, 50c is different from that in the case of direct connection, and the speed of the gear is increased. , And the ratio of rotation speeds according to the reduction ratio. Therefore, the ratio of the flow rates passing through the positive displacement fluid machines 50a, 50b, 50c also has a value corresponding to the ratio of the rotation speeds.

Further, when the coupling devices 52a, 52b are mechanisms capable of arbitrarily adjusting the acceleration / deceleration ratio by an operation from the outside, the flow rate ratio of each positive displacement fluid mechanism 50a, 50b, 50c may be arbitrarily changed to. You can It should be noted that this change is not performed by an external operation, for example, by detecting the rotational speed of the positive displacement fluid mechanism 50a, 50b, 50c, and automatically connecting when the detected value exceeds a preset value. The flow rate distribution amount may be changed by adjusting the acceleration / deceleration of the devices 52a and 52b.

Further, when the coupling devices 52a, 52b have a clutch mechanism, if the clutch mechanism is operated from the outside or is dynamically operated under a predetermined condition, each volume type Fluid mechanism 50a,
By turning off the latch mechanism when the rotational torque between 50b and 50c exceeds the allowable value, it is possible to prevent the device from being damaged by excessive torque.

In each of the above-mentioned embodiments, the roots type positive displacement fluid machine has been described. However, as shown in FIG. 7, a gear type positive displacement fluid machine 60 in which a pair of gears 62 are arranged in a body 61 is used. Also has the same effect.

〔The invention's effect〕

As described above, according to the present invention, since a plurality of positive displacement fluid machines are connected via the interlocking mechanism, the flow rate can be increased or decreased while keeping the flow rate ratio constant, and the flow resistance can be improved. Can be made smaller.

Also, by providing an acceleration / deceleration mechanism in the interlocking mechanism, it is possible to freely set the flow rate ratio of each positive displacement fluid machine, and by providing a clutch mechanism in the interlocking mechanism, it is possible to prevent equipment from being damaged by excessive torque. be able to.

[Brief description of the drawings]

FIG. 1 is an explanatory view showing the principle of a flow rate adjusting device according to the present invention, FIG. 2 is a sectional view showing the structure of a roots type positive displacement fluid machine, and FIGS. 3 (a) and 3 (b) are FIG. FIG. 4 is an explanatory diagram showing the operation of the principle diagram shown in FIG. 4, FIG. 4 is an explanatory diagram showing the first embodiment of the present invention, FIG. 5 is an explanatory diagram showing the second embodiment of the present invention, and FIG. FIG. 7 is an explanatory view showing a third embodiment, FIG. 7 is a sectional view showing the structure of a gear type positive displacement fluid machine, FIG. 8 is an explanatory view showing an example of a conventional flow rate adjusting device, and FIG. 9 is a constant flow valve. FIG. 10 is a cross-sectional view showing the configuration of FIG. 10, and FIG. 10 is an explanatory view showing another example of the conventional flow rate adjusting device. 20a, 20b, 30a, 30b, 30c, 30d, 40a, 40b, 40c, 50a, 50b, 50c, 60 …… Positive displacement fluid machine, 23,31,43,51 …… Rotary shaft, 52a, 52b …… Coupling apparatus.

Claims (3)

(57) [Claims] 1. A plurality of positive displacement fluid machines each having an independent suction port and a separate discharge port are connected through an interlocking mechanism, and the positive displacement fluid machine and the interlocking mechanism are configured so as not to be powered externally. A flow rate adjusting device characterized in that there is. 2. The flow rate adjusting device according to claim 1, wherein the interlocking mechanism includes an acceleration / deceleration mechanism between at least a pair of adjacent positive displacement fluid machines. 3. The flow rate adjusting device according to claim 1, wherein the interlocking mechanism includes a clutch mechanism that is disengaged when the transmission torque exceeds a set value.