JPH06100306B2 - Air chamber for pulsation absorption - Google Patents

Description

TECHNICAL FIELD The present invention relates to an air chamber for absorbing pulsation of a pump handling liquid.

[Conventional technology]

Generally, reciprocating pumps are provided with pulsation absorbing air chambers that utilize the cushioning action of gas to absorb the pulsation of the pumped liquid. A conventional air chamber 10 of this type (see FIG. 2) is usually composed of a cubic or tubular air chamber body 12, and a communication pipe 16 and a sluice valve 18 are provided between the body 12 and the pump pipe 14. Connected through. Then, during operation of the pump, the inside of the main body 12 is separated into a liquid region 20 and a gas region 22 which are determined according to the pressure of the liquid to be handled.

By the way, the pulsation rate δ in this type of air chamber is expressed by the following equation (1) δ = K · q / V (1) where q = the discharge volume of the pump once V = the volume of the gas region 22 K = the volume of the air chamber 10 It is represented by a constant determined by the characteristics. That is, the pulsation rate δ is proportional to the unit discharge amount q of the pump and inversely proportional to the gas volume V.

Therefore, in a device of this type, when the required pulsation rate is not achieved by a single air chamber, a plurality of air chambers are arranged in parallel to divide the unit discharge amount q, or in order to increase the gas volume V. Either using an air chamber having a large gas volume or arranging a plurality of air chambers in series, or providing a pressurizing device for the gas region in order to enlarge the gas region and increase the gas volume V, is adopted. There is.

FIG. 3 shows a case where two air chambers 10 shown in FIG. 2 are arranged in parallel, and the pulsation rate δa in this case is that the unit liquid amount to each air chamber 10 is (1/2) q. , From equation (1), δa = (1/2) K · q / V = (1/2) δ. That is, the pulsation rate is reduced to 1/2.

FIG. 4 shows a case where two air chambers 10 described above are arranged in series. In this case, the pulsation rate δb is δb1 at the first stage.
= K · q / V = δ, the discharge flow decreases to δ times the pulsation, and the discharge amount per pump flowing into the second-stage air chamber is δ times the wave size. , Q ₂ = δq
More, the second stage δb2 = K (δq) / V = δ 2 , and the ripple factor is reduced to [delta] ² times.

FIG. 5 shows an air chamber 10 with an operating valve 24 and a pressure source.
The case where the pressurizing device 28 composed of 26 is provided is shown. The pulsation rate δc in this case is calculated from the equation (1) if the gas volume Va in the gas region 22a is increased to 1.5 times the gas volume V, for example. δc = (1 / 1.5) K · q / V≈0.66δ. That is, the pulsation rate is reduced to 66%.

[Problems to be solved by the invention]

As mentioned above, in this type of air chamber,
When the required pulsation rate cannot be obtained, a plurality of air chambers are arranged side by side or a special pressure device is added.

However, as a matter of course or as is clear from FIGS. 3 to 5, these methods make the apparatus large and connect the communication pipe lines 14a and 14b (see FIGS. 3 and 4) and attached valves. Etc., or a special pressurizing device 28 which is expensive and requires maintenance. A large capacity air chamber can be used instead of the plurality of air chambers, but in this case as well, the device becomes large and a mounting space is restricted.

Therefore, an object of the present invention is to divide the inside of one air chamber into a plurality of parts, and to configure the liquid regions of these divided air chambers so that they are sequentially connected in series to the flow of the fluid. An object of the present invention is to provide an air chamber for pulsation absorption that can effectively absorb pulsation without increasing the volume of the pulsation.

[Means for solving problems]

In order to achieve the above object, the pulsation absorbing air chamber according to the present invention forms a plurality of divided air chambers each having a gas region and a liquid region by partitioning the interior of the air chamber body into upper and lower parts by partition walls. A plurality of divided air chambers are formed by communicating the liquid region of the upper divided air chamber and the liquid region of the lower divided air chamber by a resistance liquid flow passage configured to penetrate the partition wall and have a predetermined flow resistance. Are sequentially connected in series to the fluid flow.

[Action]

According to the pulsation absorbing air chamber of the present invention, the interior of the air chamber main body is divided into a plurality of divided air chambers, and the divided liquid chambers are sequentially fluidized by the resistive liquid flow passages having a predetermined flow resistance. The pulsation absorption effect in each divided air chamber can be synergistically exerted by being configured to communicate in series with the flow of, and the pulsation can be effectively absorbed without increasing the volume as a whole. be able to.

〔Example〕

An embodiment of a pulsation absorbing air chamber according to the present invention will be described below in detail with reference to the accompanying drawings.

Referring to FIG. 1, an air chamber 30 of the present invention is composed of an upper divided air chamber 36 and a lower divided air chamber 38 formed by dividing a central portion of an air chamber main body 32 by a partition wall 34, and a bottom central portion of a lower divided air chamber 38. An inflow port 40 for the liquid to be handled is provided in, and an outflow port 42 is provided in the lower end portion of the side surface of the upper split air chamber 36. A resistance liquid flow pipe 44 is arranged from the bottom surface of the upper divided air chamber 36, that is, from the partition wall 34 toward the bottom surface of the lower divided air chamber 38. The flow pipe 44 has, for example, an orifice 46 so as to impart a predetermined flow resistance to the handled liquid and divide the air chambers 36 and 3 into two parts.
It has the function of connecting 8 in series. Further, in such a configuration, during operation of the pump, the insides of the split air chambers 36, 38 are separated into gas regions 48, 50 and liquid regions 52, 54 which are determined according to the pressure of the liquid to be handled. In this case, the outflow port 42 is located in the liquid region 52, and the lower end of the flow pipe 44 is immersed in the liquid region 54.

Next, the pulsation absorbing effect of the air chamber 30 of the present invention will be described. In order to make a comparison between the air chamber 30 of the present invention and the conventional air chamber 10 shown in FIG. 2 or FIGS.
The gas volume of each split air chamber 36, 38 at V / 2
The case where the unit discharge amount is set to q will be described below. Therefore, in this case, the total capacity of the air chamber 30 and the air chamber 10 is substantially the same.

When the pulsation rate of the entire air chamber 30 is δd and the pulsation rates of the individual divided air chambers 36 and 38 are δe and δf, respectively, the pulsation rate δd is expressed by the following equation (2) δd = δe · δf (2) . In this case, the pulsation rates δe and δf are the same, and since the expression (1) is expressed by the following equation δe = δf = 2K · q / V = 2δ, the pulsation rate δ of the entire air chamber 30 is
d is represented by the following formula (3) δd = 4δ ² (3).

Therefore, a general value of 0.1 is taken as the pulsation rate δ of the conventional air chamber 10 and the pulsation rate δd of the air chamber 30 is calculated from the above equation (3) as follows: δd = 4δ ² = 4 · (0.1) ² = 0.04 Become. In this case, the conventional air chamber 10 (δ
= 0.1), the pulsation rate is 40%. That is, according to the air chamber 30 of the present invention, it is shown that the pulsation is remarkably effectively absorbed as compared with the conventional air chamber 10 with a single air chamber and without increasing the volume thereof.

Although the preferred embodiments of the present invention have been described above, the present invention can be modified in many ways without departing from the spirit thereof. For example, the split air chambers can be formed in three rows in the vertical direction, or can be formed in two or three rows in the horizontal direction.

〔The invention's effect〕

As described above, in the pulsation absorbing air chamber of the present invention, the interior of the air chamber body is divided into a plurality of divided air chambers, and these divided air chambers are respectively separated by the resistance liquid flow passage having a predetermined flow resistance. By configuring the liquid region to communicate in series with the flow of fluid, the pulsation absorption effect in each divided air chamber can be synergistically exerted, and pulsation can be generated without increasing the volume as a whole. Can be effectively absorbed.

As described above, since the pulsation rate is the ratio δ of the flow rate deviation ΔQ to the average flow rate, δ = ΔQ /, the magnitude of the discontinuous flow of the reciprocating pump, that is, the smaller the discharge amount at one time, Further, the larger the gas volume for pulsation absorption, the smaller the pulsation rate δ, and δ = K · q / V.

From this, when the air chambers are divided into n and arranged in parallel, the flow rate of the pump is q / n and the gas volume of the air chamber is V / n, so the pulsation rate δ is
δ = K (q / n) / (V / n) = K · q / V, and the pulsation rate does not change.

On the other hand, if the air chambers divided into n pieces are alternately arranged in series with the throttle resistances of n pieces, the flow rate does not change, so the pulsation rate δ1 at the first stage is δ1 = K · q / (V / n ) ＝ nK
・ Q / V = nδ, and the flow has a pulsation of flow rate deviation ΔQ1 = nδ. This flow enters the second stage, and the pulsation rate δ2 is δ2 = K (nδ) / (V / n) = n ² δK · q
/ V = n ² δ ² , and the pulsation rate δn = (nδ) ^{2 at} the nth stage.

Therefore, for example, if δ = 0.1 and n = 2, then δ2 = (2
× 0.1) ² = 0.04, which means that the pulsation rate is 10% in the case of parallel connection, but can be reduced to 4% in the case of series connection.

If n = 3, then δ3 = 0.008, and the pulsation rate is
It can be reduced to 0.8%. In order to effectively function the air chambers, it is needless to say that fluid resistance means is appropriately provided on the downstream side of each air chamber.

In this way, according to the present invention, small and lightweight,
Moreover, a highly efficient pulsation absorbing air chamber can be obtained.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of a pulsation absorbing air chamber according to the present invention, FIG. 2 is a sectional view showing a conventional pulsation absorbing air chamber, and FIG. 3 is a parallel arrangement of two air chambers shown in FIG. Fig. 4 is a configuration diagram of the case where two air chambers shown in Fig. 2 are arranged in series, and Fig. 5 is a configuration diagram of a case where a pressure device is attached to the air chamber shown in Fig. 2. FIG. 30 …… Air chamber 32 …… Air chamber body 34 …… Differential wall 36 …… Upper split air chamber 38 …… Lower split air chamber 40 …… Inlet port, 42 …… Outlet port 44 …… Resistance liquid flow pipe, 46 …… Olifis 48, 50 …… Gas region 52,54 …… Liquid region

Claims (1)

[Claims] 1. A plurality of divided air chambers each having a gas region and a liquid region are formed by partitioning the interior of an air chamber body into upper and lower parts by partition walls, and a liquid region of the upper divided air chamber and a lower divided air chamber. And a liquid region of the plurality of divided air chambers are connected to each other in series with respect to the flow of the fluid in sequence by communicating with the liquid region of the liquid region by a resistance liquid flow passage configured to penetrate the partition wall and have a predetermined flow resistance. An air chamber for pulsation absorption.