JPH03111915A - Flow rate controller - Google Patents

Abstract

PURPOSE:To realize constant rate exhaust, to slow down variation in a drawing variable accompanying control operation and to attain flow rate control capable of prevent a passage from being jammed by foreign substances by changing the inserted length of a rod material for changing the practical length of a groove part to control the drawing variable. CONSTITUTION:The flow rate controller is constituted of the rod material 1 and a cylindrical body 2 into which the rod material 1 is to be inserted. The rod material 1 is provided with the groove part 10 extended from one end to the other on its outer peripheral face in the axial direction, and when the shape of the groove is adjusted to the shape of a screw regulated by JIS, the flow rate controller can be formed by using existing equipments or jigs. The cylindrical body 2 is formed by a flexible material, its inner diameter is smaller than the outline of a top part 11 between grooves 10 of the rod material 1 and the rod material is inserted into the cylindrical body 2 by pressure. Fluid discharged from a pump 3 is drawn at the time of passing the passage formed of the groove part 10 and the inner periphery of the cylindrical body 2.

Description

[Detailed description of the invention] [Industrial application field]

The present invention relates to a flow rate adjustment device for adjusting the discharge flow rate and exhaust flow rate of a pump.

[Conventional technology]

2. Description of the Related Art Conventionally, as a flow rate adjusting device that is connected to the discharge port side of a pump and throttles the discharge amount of the pump, there has been provided a device that narrows the cross-sectional area of a flow path by a combination of a tapered hole and a shaft. Furthermore, some flow path regulating devices used in blood pressure monitors are capable of reducing the exhaust pressure at a constant speed even if the exhaust pressure changes. FIG. 9 shows this type of flow path adjustment device described in Japanese Utility Model Publication No. 14809/1980, which is formed of a flexible material into a cylindrical shape with a bottom, and has a cylindrical shape along the outer peripheral surface in the longitudinal direction. The sleeve 8 in which the slit 80 is provided is placed in the pilot pressure chamber 60 provided in the vessel body 6, and the tip of the adjustment screw 7 applies pressure to the sleeve 8 in which the flange 81 is clamped and fixed. By adding and deforming the sleeve 8, which originally had the shape shown in FIG. 10(a), the slit 80 is opened as shown in FIG. 10(b), and the exhaust gas is The fluid entering the pilot pressure chamber 60 flows through the slit 8 from the outer circumferential side of the sleeve 8.
0 into the sleeve 8 and exits through the exhaust hole 70 passing through the adjusting screw 7. When the pressure of the fluid to be exhausted is high, this pressure is applied to the outer peripheral surface of the sleeve 8, causing the sleeve 8 to resist its elasticity and reduce the opening area of the slit 80, as shown in FIG. 10(c). If the pressure of the fluid becomes lower, the opening area of the slit 80 becomes larger, so that the exhaust pressure can be reduced at a constant speed.

[Problem to be solved by the invention]

The above-mentioned flow rate regulating device, which consists of a tapered hole and a shaft, must have a considerably small cross-sectional area in order to restrict the flow rate to a large extent. In addition, in order to obtain the desired indigo color, the machining precision of the parts must be high, and there is a problem that the cost is high due to the large number of parts. ing. The above-mentioned flow rate adjustment device, which is capable of performing constant-speed exhaust, requires an adjustment screw because its characteristics vary greatly depending on the length of the sleeve 1 and the material of the sleeve. Screws have a problem in that they are difficult to adjust because the opening amount of the slit changes greatly with just a slight rotation. The present invention has been made in view of these points, and its purpose is to provide a flow rate regulating device that has a small number of parts, can be provided at low cost, and is less likely to be clogged with foreign matter. To provide a flow rate adjustment device that can perform quick exhaust and is easy to adjust.

[Means to solve the problem]

Therefore, the flow rate regulating device according to the present invention includes a rod-shaped member having a continuous groove on its outer circumferential surface from one end in the axial direction to the other end, and a rod-shaped member that is inserted into the inner circumferential surface of the rod-shaped member. and a cylindrical body constituting a flow path formed by the groove between the cylindrical body and the cylindrical body, and the cylindrical body is made of a flexible material, and the rod-shaped body is formed of a flexible material. The second feature is that the insertion of the material is variable and the cylinder is disposed within a pilot pressure chamber that applies pilot pressure to the outer peripheral surface of the cylinder. [Function] According to the first feature of the present invention, it can be constructed only from a rod-shaped member and a cylinder, and since the length of the rod-shaped member is utilized, the cross-sectional area of the groove portion is not small. According to the second feature, the exhaust pressure can be reduced at a constant speed by deformation of the cylindrical body by pilot pressure, and the time required for inserting the bar material is reduced. Since the aperture color is adjusted by changing the actual length of the groove, the variation in the aperture color due to the adjustment operation is gentle and adjustment is easy. [Example] The present invention will be described in detail below based on the illustrated example. As shown in FIG. It is composed of a cylindrical body 2. The rod-shaped member 1 is provided with a groove 10 extending from one end in the axial direction to the other end on its outer peripheral surface, and in this example, the groove 10 having a triangular cross section is formed in a spiral shape. If the shape of the groove 10 is matched to the shape of a screw defined by JIS, it is convenient because it can be created using existing equipment and jigs. The cylindrical body 2 is made of a flexible material, and its inner diameter is smaller than the outer diameter of the crest 11 between the grooves 10 of the rod-shaped member 1. Therefore, the rod-shaped member 1 cannot be inserted into the cylindrical body 2. It is made by press fitting. As shown in FIG. 3, for example, this flow rate adjustment device is used with one end of the cylinder 2 connected to the discharge port 30 of the pump 3, and the fluid discharged from the pump 3 is in the form of a rod. When passing through the flow path formed by the groove 10 of the material 1 and the inner circumferential surface of the cylinder 2, the flow rate is restricted. Here, the relationship between pressure and flow rate when fluid flows through a narrow channel is generally expressed by the following equation. Q: Flow rate 1: Length of channel b Width of two channels γ: Specific gravity of raw fluid h: Depth of channel μ: Coefficient of raw fluid viscosity P: Bomb discharge pressure X, : Constant determined by the ratio of b and h In other words, in order to reduce the flow rate, in addition to reducing the cross-sectional nature of the flow path, the flow path may also be lengthened. By doing so, it is possible to narrow down the flow to the required flow rate without reducing the cross-sectional area of the flow path very much.In particular, the groove portion 10 of the rod-shaped material 1 shown here has a spiral shape as described above. Because of this, the flow path is considerably longer than the entire axial length of the rod-shaped material 1, so there is no need to reduce the cross-sectional area of the flow path, and the risk of clogging with foreign matter is reduced. It is something that exists. As shown in FIG. 2, the top of the crest 11 on the bar 1 is rounded so that the inner surface of the cylindrical body 2 is not scraped when the bar 1 is press-fitted into the cylindrical body 2. This prevents debris from entering the JO and causing clogging. The cylindrical body 2 does not need to be made of a flexible material, and the diameter of the crest 11 of the bar-shaped material 1 and the inner diameter of the cylindrical body 2 can be precisely machined to make the crest 11 of the bar-shaped material 1 and the inner diameter of the cylindrical body 2. The cylindrical body 2 may be made of a highly rigid material as long as there is no gap between the cylindrical body 2 and the surrounding surface.If the cylindrical body 2 is made of a flexible material, When used in an atmosphere where pressure is applied to the outer peripheral surface of the tube, the cylinder 2 deforms and changes the cross-sectional area of the flow path formed by the inner peripheral surface of the cylinder 2 and the groove 10. The flow rate will change. Therefore, in such a case, it is preferable that the cylindrical body 2 be made of a highly rigid material, but normally there is no problem even if the cylindrical body 2 is made of a flexible material, and it can be manufactured at a low cost. Moreover, the cross-sectional shapes of the rod-shaped material 1 and the cylinder body 2 are most preferably circular in view of workability, but are not limited to this. The groove 10 does not have to be formed spirally or have a triangular cross section; for example, the groove 10 having a rectangular cross section may be formed linearly, as shown in FIGS. 4 and 5. It is something. Furthermore, instead of completely inserting the rod-shaped member 1 into the cylinder 2, as shown in FIG. If the insertion amount of the bar 1 is made variable, the amount of flow restriction can be adjusted by changing the insertion amount.12 in the figure is a groove formed at one end of the bar 1. When changing the insertion amount, by engaging the tip of the driver with the rod-shaped material 1, the existence of the spiral groove 10 (peak portion 11) can be used to easily change the insertion amount of the rod-shaped material 1. 35 in the figure 0 is a connecting pipe for connecting the cylindrical body 2 to other things. The flow rate regulating device shown in FIGS. 7 and 8 is used as a constant speed exhaust valve for a blood pressure monitor, and has a cylindrical body 2 made of a highly flexible material, and a rod-like material 1. is inserted into the cylindrical body 2 with one end protruding from the cylindrical body 2. Then, attach the flange 21 provided at one end of the cylinder 2 to the container 6.
By clamping it between the inner surface of and the fixing screw 65,
The cylindrical body 2 is arranged in the pilot pressure chamber 60 of the vessel body 6, and the exhaust is made to flow from the pilot pressure chamber 60 through the inside of the cylindrical body 2. 66 in the figure is a tool engagement provided on the fixing screw 65. It's a groove. On the outer circumferential surface of the cylinder body 2 arranged in the pilot pressure chamber 60,
The pressure of the fluid to be evacuated is applied, and when this pressure is low, the cylinder body 2 is hardly deformed, as shown in FIG. 8(a), but when the pressure of the fluid is high, the cylinder body 2 deforms. The inner surface of the cylinder 2 and the groove 10 are deformed as shown in FIG.
further reduce the cross-sectional area of the flow path formed between the For this reason, when the exhaust pressure is high, the exhaust speed is high and the flow rate is low, and as the exhaust pressure is low, the exhaust speed is slow and the flow rate is high, so that the exhaust pressure can be reduced at a constant speed. The displacement amount can be adjusted at this time by adjusting the insertion amount of the rod-shaped material 1 into the cylinder body 2, and since the flow rate changes gently in response to changes in the insertion amount, the adjustment is easy. It is something. Here, the case is shown in which the fluid that is introduced into the pilot pressure chamber 60 and applies pressure to the outer circumferential surface of the cylinder body 2 is the fluid itself to be exhausted, but it is also possible to apply pressure for other groove control purposes. Of course, it may be.

【Effect of the invention】

As described above, the flow rate regulating device according to the present invention can be configured with only a rod-shaped member and a cylinder, and since the length of the rod-shaped member is utilized, the flow rate can be effectively controlled even if the cross-sectional area of the groove is not small. It can be narrowed down to a small amount, and there is little risk of foreign matter becoming clogged. The second feature is that constant-speed exhaust depressurization can be performed by deforming the cylinder body using pilot pressure, and the actual length of the groove can be reduced by changing the insertion type of the rod-shaped member. Since the amount of aperture is adjusted by changing the amount of aperture, fluctuations in the amount of aperture caused by the adjustment operation are gradual and adjustment is easy.

[Brief explanation of drawings]

FIG. 1 is a sectional view of one embodiment of the present invention, FIG. 2 is an enlarged sectional view of the same, FIG. 3 is a front view of the same, FIG. 4 is a front view of another example, and FIG. , FIG. 6 is a cutaway front view of another embodiment, FIG. 7 is a sectional view of another embodiment, and FIG.
a) (b) are enlarged sectional views showing the same effect as above, FIG. 9 is a sectional view of the conventional example, and FIGS. 10 (a), (b), and (c) are front views showing the same effect, is a rod-shaped material, 2 is a cylinder, 6
10 indicates a container body, 10 indicates a groove portion, and 60 indicates a pilot pressure chamber.

Claims (2)

[Claims] (1) A rod-shaped member with a groove on its outer circumferential surface that continues from one end in the axial direction to the other end, and this rod-shaped member is inserted into the inside and the groove is formed between the inner circumferential surface and the rod-shaped member. 1. A flow rate regulating device comprising: a cylindrical body constituting a flow path in which the flow rate is adjusted; (2) In the flow rate regulator according to claim 1, the cylinder is formed of a flexible material, the amount of insertion of the rod-shaped member into the cylinder is variable, and pilot pressure is applied to the outer circumferential surface of the cylinder. A flow rate regulating device characterized by having a cylindrical body arranged inside the room.