JP3241424U - pumping equipment - Google Patents

Abstract

A pump device capable of stably delivering fluid over a long period of time by suppressing deterioration of a tube that may adversely affect the delivery of fluid. A flexible tube (10), a compression plate (40) having a support surface (41) for the tube (10), a compression roller (30) for compressing the tube (10) between the support surface (41), and the compression roller (30). along the support surface 41 to move the fluid in the tube 10 in the direction of roller movement, and the compression plate 40 has, at the end of the support surface 41, A relief shape portion 42 formed by a curved surface continuous with the support surface 41 is provided. [Selection drawing] Fig. 1

Description

The present invention relates to pumping devices, in particular pumping devices called peristaltic, peristaltic, tube or roller pumps.

For example, in technical fields such as medical equipment and food processing machines, pump devices called peristaltic pumps, peristaltic pumps, tube pumps, or roller pumps are sometimes used. Such a pump device compresses a flexible tube with a compressing plate and a compressing roller, and moves the compressed portion by rotating the compressing roller, thereby pumping out the fluid in the tube in the roller moving direction. is configured (see, for example, Patent Document 1).

Japanese Utility Model Laid-Open No. 57-026689

SUMMARY OF THE INVENTION An object of the present invention is to provide a pump device capable of stably delivering fluid over a long period of time by suppressing deterioration of a tube that may adversely affect delivery of fluid.

One aspect of the present invention was devised to achieve the above object,
a flexible tube;
a squeeze plate having a support surface for the tube;
a squeezing roller for squeezing the tube against the support surface;
a roller moving mechanism for sending the fluid in the tube in the direction of roller movement by moving the compression roller along the support surface;
In the pump device, the compression plate is provided with a relief shape formed by a curved surface continuous with the support surface at the end of the support surface.

ADVANTAGE OF THE INVENTION According to this invention, deterioration of a tube which may adversely affect delivery of fluid can be suppressed, so that fluid can be stably delivered over a long period of time.

BRIEF DESCRIPTION OF THE DRAWINGS It is explanatory drawing which shows typically the schematic structural example of the pump apparatus which concerns on one Embodiment of this invention. FIG. 4 is an explanatory diagram (part 1) showing a specific example of change in flow rate of the pump device; FIG. 11 is an explanatory diagram (part 2) showing a specific example of change in flow rate of the pump device; It is an explanatory view showing typically a schematic structure of an example of the conventional pump device.

A pump device according to the present invention will be described below with reference to the drawings.

<1. Overview of the pump device>
The pump device described in this embodiment is called a peristaltic pump, a peristaltic pump, a tube pump, or a roller pump, which compresses a flexible tube and moves the compressed portion along the extending direction of the tube. Thus, it is configured to deliver the fluid in the tube. Specifically, for example, as shown in FIG. 4, a plurality of pressing rollers 102 are arranged evenly on the circumference of a rotating body 101, and a pressing plate 104 having a support surface 103 facing each pressing roller 102. A device is known in which fluid in the tube 105 is sent out by rotating the rotor 101 while pressing the tube 105 with the support surface 103 and the compression rollers 102 .

According to the pump device having such a configuration, only the tube 105 is in contact with the fluid, and the fluid can be delivered without contacting other pump constituent members. Therefore, it is widely used especially in technical fields such as medical equipment and food processing machines to deliver fluids such as chemical liquids and solutions.

<2. Inventor's Knowledge>
By the way, the above-described pump device has a structure in which fluid is delivered by utilizing peristaltic motion generated by moving the tube pressure portion (hereafter, a pump device with such a structure is also simply referred to as a "peristaltic pump"). degradation can have a significant impact on fluid delivery. For example, deterioration of the tube may cause the flow rate of the fluid to fluctuate, or breakage of the tube may prevent the fluid from being delivered. Therefore, peristaltic pumps are required to be able to stably deliver fluid over a long period of time by suppressing tube deterioration that may adversely affect delivery of fluid.

It was thought that factors such as fluid flow rate fluctuations and tube breakage mainly depended on the material of the tube. We have come to the knowledge that it is greatly related to the structure. Specifically, as shown in FIG. 4, for example, if the end of the support surface 103 of the compression plate 104 is square (see arrow G in the figure), the repeated bending of the tube 105 at that portion will Deterioration or breakage of the tube 105 is likely to occur.

The peristaltic pump described as an example in the present embodiment has been newly invented based on the knowledge of the inventor of the present application described above, and has the characteristic configuration described below.

<3. Configuration of pump device>
As shown in FIG. 1, the peristaltic pump of this embodiment includes a flexible tubular tube 10 and a rotating body 20 as a roller moving mechanism that is rotationally driven by a drive source such as a motor (not shown). , a plurality of compression rollers 30 evenly arranged on the circumference of the rotating body 20, a compression plate 40 having a support surface 41 facing each compression roller 30, a tube support 50 for supporting the tube 10, It has The tube 10 is supported by the tube support 50 so that the tube 10 passes between the support surface 41 of the compression plate 40 and the compression rollers 30 arranged on the rotating body 20 .

In such a peristaltic pump, each squeezing roller 30 presses against the support surface 41 of the squeezing plate 40 against the tube 10 . By rotating the rotating body 20 (for example, rotating clockwise in the figure), each pressing roller 30 is moved along the support surface 41 . This causes a peristaltic movement within the tube 10 due to the movement of the pressure point. Using this peristaltic motion, the fluid in the tube 10 will be delivered in the direction of movement of each compression roller 30 .

Each component in the peristaltic pump will be described in more detail below.

(tube)
The tube 10 serves as a fluid flow path. However, since the fluid is delivered using peristaltic motion, it is essential that the tube 10 has flexibility. As the flexible tube 10, for example, a so-called silicone tube made of silicone rubber can be used.

By the way, as described above, the factors that cause tube deterioration and the like are largely related to the structure of the mechanical portion of the peristaltic pump. On the other hand, considering that the tube 10 is repeatedly compressed by the squeezing rollers 30, the dependence on the tube material cannot be ruled out.

Based on this fact, it is preferable to use an unsaturated hydrocarbon compound as a forming material for the tube 10 . The unsaturated hydrocarbon compound is a polymer compound such as ethylene, propylene, butadiene, and is also called olefin, and typical examples thereof include polypropylene (PP) and polyethylene (PE). That is, it is preferable to use a so-called olefin tube made of PP, PE, or the like, for example, as the tube 10 in order to suppress deterioration or breakage and to stably deliver the fluid over a long period of time.

Note that the tube 10 is detachably supported by the tube support 50 . If it is detachable, cleaning and replacement of the tube 10 can be easily performed. A specific configuration of the tube support 50 that allows attachment and detachment of the tube 10 will be described in detail later.

(pressing roller)
The compression roller 30 presses the tube 10 between itself and the support surface 41 of the compression plate 40, and moves the pressed portion with the rotation of the rotating body 20, thereby causing peristaltic motion in the tube 10. . Therefore, the pressing roller 30 is formed in a rotatable columnar shape, for example, from a metal material or a resin material.

The squeezing rollers 30 that can be used for peristaltic pumps are roughly classified into gear type and self-propelled type. The gear type is a type in which the compression roller 30 is gear-driven and rotated as the rotating body 20 rotates. In the self-propelled type, the pressing roller 30 is supported so as to be freely rotatable, and when it comes into contact with the tube 10 while the rotor 20 is rotating, it is driven to rotate by the frictional resistance.

As the pressing roller 30, either a gear type or a self-propelled type may be used. However, for the reasons described below, it is preferable to use a self-propelled compression roller 30 in order to suppress deterioration of the tube 10 and to stably deliver the fluid over a long period of time.

For example, when the rotating body 20 rotates in one direction (for example, clockwise direction; see arrow A in the drawing), the gear-type pressing roller 30 rotates in the opposite direction to the rotating body 20 (for example, counterclockwise direction). direction (see arrow B in the figure). At this time, if the circumferential speed of the rotating body 20 and the circumferential speed of the compressing roller 30 do not completely match at the point where the compressing roller 30 contacts the tube 10, the tube 10 is stretched in the direction of stretching (that is, in the direction of the tube axis). ), or conversely, a force that tries to return it. However, it is not necessarily easy to completely match the respective peripheral speeds. Therefore, while the tube 10 is being pressed by the compression roller 30, the tube 10 continues to be stressed with a load that tends to deform it in the tube axis direction (that is, a load in the direction of extension or a load in the direction of contraction). . Stress on the tube 10 can lead to variations in the inner diameter of the tube 10 leading to fluctuations in the fluid flow rate.

On the other hand, the self-propelled compression roller 30 is driven to rotate by the frictional resistance generated by contact with the tube 10, so the stress on the tube 10 can be reduced compared to the case of the gear type. Therefore, it is preferable to use the self-propelled compression roller 30 in order to suppress the deterioration of the tube 10 and stabilize the delivery of the fluid.

In the case of using the self-propelled compression roller 30, in order to reliably reduce the stress on the tube 10, it is necessary to reduce the rotational resistance of the compression roller 30 and rotate it smoothly. Therefore, it is preferable that the pressing roller 30 is attached to the roller support shaft provided on the rotating body 20 using a bearing mechanism such as a rolling bearing. This is because the use of the bearing mechanism enables the pressing roller 30 to rotate smoothly.

Moreover, it is preferable that the pressing roller 30 is attached to the rotating body 20 not by cantilever support but by both end support. In the cantilever support, the roller support shaft is flexed (that is, the compression roller 30 is tilted) due to the load when the tube is compressed, which can cause fluctuations in the inner diameter of the tube 10 (that is, fluctuations in the flow rate). This is because the occurrence of tilting of the pressing roller 30 can be suppressed if both ends are supported. Specifically, it is conceivable to support both shaft ends of the pressing roller 30 using bearing mechanisms.

A plurality of pressing rollers 30 are evenly arranged on the same circumference when the rotating body 20 rotates. Specifically, for example, 12 pressing rollers 30 are arranged at an equal pitch. Although the number of pressing rollers 30 arranged is not particularly limited, it is preferable to increase the number to the extent that the peristaltic motion in the tube 10 is not hindered. For example, while a general peristaltic pump has about 6 rollers (see FIG. 4), it is preferable to arrange 12 pressing rollers 30, which is more than this. If the number of squeezing rollers 30 arranged is large, even if the rotation speed of the rotating body 20 is the same, the number of places where the tube 10 is pressed per unit time increases, so that it can contribute to the stabilization of fluid delivery. Because it becomes

(squeeze plate)
The compression plate 40 is arranged further on the outer peripheral side than the compression roller 30 arranged on the rotating body 20, and is configured to support the tube 10 compressed by the compression roller 30 from the opposite side of the compression roller 30. is. To that end, the squeeze plate 40 has a support surface 41 for the tube 10 .

Since the compression plate 40 having the support surface 41 is in direct contact with the tube 10, polyacetal, which is a forming material capable of realizing a smooth surface, is used to reduce the stress on the tube 10. It is conceivable to form it with a resin material such as (POM). However, the tube 10 is not limited to this, and may be made of other material as long as it can realize a surface that reduces stress on the tube 10 .

Since the support surface 41 of the compression plate 40 supports the tube 10 from the opposite side of the compression roller 30, it is composed of a curved surface along a virtual circle corresponding to the trajectory drawn by the outer edge of the compression roller 30. It is More specifically, it is configured by a curved surface having a radius of curvature equal to the radius of the virtual circle plus the width of the compressed tube 10 .

In addition, the support surface 41 is configured so that the curved surface is continuous over the arrangement range of at least three compression rollers 30 (see, for example, arrow C in the drawing) in the direction of elongation of the tube 10 (that is, the direction of the tube axis). there is Since the number is at least three, the support surface 41 may be formed over the arrangement range of four or more pressing rollers 30 . Such a range is a necessary and sufficient range for causing peristaltic motion within the tube 10 . That is, by forming the support surface 41 so that the curved surface is continuous over such a range, and by adopting a structure in which the compression roller 30 moves while compressing the tube 10 from the opposite side thereof, it is possible to deliver the fluid inside the tube 10. It becomes.

By the way, as described above, the factors that cause tube deterioration and the like are largely related to the structure of the mechanical portion of the peristaltic pump. Specifically, for example, if the end portion of the supporting surface is angular, the tube 10 is likely to deteriorate or break at that portion.

For this reason, in the present embodiment, the compression plate 40 has a relief shape portion 42 formed by a curved surface continuing to the support surface 41 at the end of the support surface 41 (see, for example, point D in the drawing). is provided. By providing the relief shape portion 42 , the pressing plate 40 follows the trajectory of the pressing roller 30 as the surface of the pressing plate 40 facing the pressing roller 30 moves away from the support surface 41 (that is, closer to the edge of the plate). It is designed to run away from the corresponding virtual circle (that is, to increase the distance between them). Note that the relief shape portions 42 are provided corresponding to both end portions of the support surface 41 respectively.

Since the curved surface forming the relief shape portion 42 forms a relief from the virtual circle, it is assumed to be curved in the opposite direction to the curved surface forming the support surface 41 . Note that the radius of curvature of the curve is not particularly limited, and may be any value necessary and sufficient for forming a relief from the virtual circle. Further, the range in which the curved surface forming the relief shape portion 42 is arranged (see, for example, arrow E in the figure) is not particularly limited, either, and is necessary and sufficient for forming the relief from the virtual circle. If it is

In the compression plate 40 provided with such a relief shape portion 42, the curved surface forming the support surface 41 and the curved surface forming the relief shape portion 42 are continuous. does not become angular. Therefore, deterioration or breakage of the tube 10 at the end of the support surface 41 can be suppressed.

In a peristaltic pump configured to move the compression roller 30 by rotating the rotating body 20, compression deformation of the tube 10 occurs at a point where the compression roller 30 begins to come into contact with the tube 10 (for example, see point D in the figure), There is a concern that the tube 10 is likely to be deteriorated or ruptured due to the load due to the deformation.

However, in the present embodiment, since the compression plate 40 is provided with the relief shape portion 42 , the relief is ensured on the side of the compression plate 40 at the point where the compression roller 30 starts contacting the tube 10 . Become. Therefore, compared to the case where there is no relief, the load applied to the tube 10 by contact with the pressing roller 30 can be reduced, and deterioration or breakage of the tube 10 can be suppressed. It is possible to greatly extend the life of the

Moreover, if the pressing plate 40 is provided with the relief shape portion 42, when the pressing roller 30 passes the point where the pressing roller 30 starts to contact the tube 10 and further moves in the rotation direction of the rotating body 20, the pressing roller 30 is The distance between roller 30 and compression plate 40 will gradually narrow. Therefore, the tube 10 sandwiched between them is compressed from both the compression roller 30 side and the compression plate 40 side in such a manner that the pressure is gradually increased. When compression is performed in this manner, an excessive load is not generated locally, so deterioration or rupture of the tube 10 can be suppressed, and as a result, the life of the tube 10 can be extended. It can be extended significantly. Moreover, since the pressure is gradually increased from both sides to compress the tube 10, it is very suitable for generating peristaltic movement in the tube 10, and as a result, the fluid is kept stable for a long period of time. It becomes feasible to transmit

(tube support)
The tube support 50 supports the tube 10 so that the tube 10 passes between the squeezing roller 30 and the squeezing plate 40 . The tube 10 is supported on the fluid inflow side (i.e., upstream of the pressure point of the tube 10 by the support surface 41 and the squeeze rollers 30) and on the fluid outflow side (i.e., the pressure point of the tube 10 by the support surface 41 and the squeeze rollers 30). on the downstream side). For this purpose, the tube supports 50 are arranged on the upstream side and the downstream side of the compressed portion of the tube 10 .

Each of the tube supports 50 arranged on the upstream side and the downstream side is made of, for example, a metal material or a resin material and has a cubic shape. A locking hole 52 having a larger diameter is provided. By engaging the locking piece 11 attached to the end of the tube 10 with the locking hole 52 , the tube 10 is attached to the tube supporting member so that the tube 10 does not fall out to the through hole 51 side. 50 has a structure to support. With this construction, the tube 10 is placed between the squeezing roller 30 and the squeezing plate 40 with some tension between the upstream tube support 50 and the downstream tube support 50 . supported to pass through

Since the tube 10 supported by the tube support 50 is compressed by the compression roller 30 and the compression plate 40, due to deformation due to the compression, the tube length increases over time from the tube length at the start of pump operation. Such elongation may occur. However, according to the support structure described above, each tube support member 50 supports the tube 10 by locking the locking piece 11 and the locking hole 52, so that there is play in the direction in which the tube 10 extends. Become. In other words, the tube support 50 supports the tube 10 in a manner that allows displacement of the support position in the direction in which the tube 10 extends. Therefore, even if the tube 10 expands due to deformation due to compression, the expansion is absorbed by the support structure of the tube support 50, which is very useful for stable delivery of fluid over a long period of time. is preferred for

The support surface 41 of the compression plate 40 and the compression roller 30 for pressing the tube 10 supported by the tube support 50 are configured to have a shape that allows displacement of the tube 10 in the axial direction of the compression roller 30. is preferred. Specifically, for example, the compression roller 30 may be configured to have an axial length that allows displacement of the tube 10 in the axial direction. Further, for example, the support surface 41 of the compression plate 40 may be configured to be a curved surface having a surface width approximately equal to the axial length of the compression roller 30 . A force that tends to displace the tube 10 in a direction perpendicular to the tube axis direction (that is, in the roller axis direction) may act on the tube 10 due to compression. In that case, for example, if the compression roller 30 or the support surface 41 is configured to limit the displacement of the tube 10 in the roller axial direction, the tube 10 is likely to deteriorate or break due to the load caused by the limitation. It is feared that On the other hand, if the support surface 41 and the compression roller 30 are configured to have a shape that allows the tube 10 to be displaced in the roller axial direction, the load on the tube 10 can be reduced and deterioration or breakage of the tube 10 can be prevented. This can be suppressed, and as a result, the life of the tube 10 can be greatly extended.

A tube support 50 that supports the tube 10 has a slit-shaped tube attachment/detachment groove (not shown) that communicates with the outer surface of the tube 10 and the through hole 51 and locking hole 52 . The groove width of the tube attachment/detachment groove is the width through which the tube 10 passes. With such a configuration, the tube support 50 can detachably support the tube 10 . For example, when removing the tube 10 from the tube support 50, the tube 10 can be removed by pulling the tube 10 so as to release the engagement between the locking piece 11 and the locking hole 52, and using the groove for attaching and detaching the tube. should be positioned outside the tube support 50 . If the tube 10 can be attached and detached in this manner, cleaning and replacement of the tube 10 can be easily performed.

<4. Effect of the present embodiment>
According to this embodiment, one or more of the following effects can be obtained.

(a) In the present embodiment, since the end of the support surface 41 of the compression plate 40 is provided with the relief shape portion 42, the end of the support surface 41 does not become square, and the support surface 41 It is possible to suppress deterioration or rupture of the tube 10 at the end of the tube 10 . If deterioration or rupture of the tube 10 can be suppressed, the life of the tube 10 can be greatly extended as a result, and fluid delivery using the tube 10 is not adversely affected. In this way, by eliminating adverse effects on fluid delivery, it is well suited to create peristaltic motion within the tube 10, resulting in stable fluid delivery over an extended period of time. It becomes possible.
That is, according to the present embodiment, it is possible to suppress deterioration of the tube 10, which may adversely affect delivery of the fluid, thereby enabling stable delivery of the fluid over a long period of time.

Here, a specific example will be given to explain how to stably deliver a fluid over a long period of time. It should be noted that the flow rate measurement of the fluid is performed using a flow meter (not shown) connected to the upstream side of the tube. When measuring a flow rate using a flow meter, since the flow rate measurement takes a long time, the fluid sent by the peristaltic pump is returned to the reservoir so that the fluid can be circulated and used.
For example, as shown in FIG. 2(b), with a general peristaltic pump (see FIG. 4), it is known that the flow rate of the fluid to be delivered decreases over time (especially during the period immediately after the start of operation). ing. One of the reasons for this is considered to be deterioration due to repeated bending of the tube. On the other hand, according to the peristaltic pump (see FIG. 1) described in this embodiment, deterioration or rupture of the tube 10 can be suppressed, so as shown in FIG. It can be seen that even if there is, the reduction in the delivered fluid flow rate over time can be suppressed. That is, it has been confirmed that the peristaltic pump according to the present embodiment can stably deliver fluid over a long period of time.

(b) As described in this embodiment, the tube 10 serving as a fluid flow path is supported in such a manner as to allow displacement in the axial direction of the roller during compression and displacement in the support position in the direction of elongation. setting the number of rollers arranged so that the number of pressure points generated per unit time increases; or using an unsaturated hydrocarbon compound as a tube-forming material, or a plurality of these. By appropriately combining them, it is possible to further stabilize the delivery of the fluid.

For example, as shown in FIG. 3, the flow rate of the fluid tends to stabilize after 24 hours from the start of pump operation, but then gradually progresses. One reason for this is considered to be the deformation of the tube 10 . In addition, the presence of dotted plots in the figure is presumed to be caused by the generation of wear residue of the silicon tube, which is detected when passing through the flow meter.
On the other hand, as described in the present embodiment, if the displacement of the tube 10 is allowed, or if an unsaturated hydrocarbon compound is used as the forming material, the flow rate fluctuation due to the deformation of the tube 10 and the wear debris can be reduced. Since it is possible to suppress the occurrence of such a phenomenon, it is very preferable for stable delivery of the fluid over a long period of time.

<5. Modifications, etc.>
Although the embodiments of the present invention have been specifically described above, the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the scope of the invention.

For example, the number of arrangement of the compression rollers 30 and the shape of the compression plate 40 constituting the peristaltic pump are not limited to the configurations exemplified in the above-described embodiment, and may be determined according to the purpose of use of the pump, the environment of use, and the like. can be changed as appropriate. The same applies to the length, diameter, etc. of the tube 10 .

Also, the number of tubes 10 is not particularly limited. For example, one tube 10 may pass between the support surface 41 of the compression plate 40 and the compression roller 30, but is not limited to this, and a plurality of tubes 10 may be inserted. It does not matter if the configuration is such that they are passed in line.

DESCRIPTION OF SYMBOLS 10... Tube, 20... Rotating body, 30... Squeezing roller, 40... Squeezing plate, 41... Support surface, 42... Relief shape part, 50... Tube support

Claims (3)

a flexible tube;
a squeeze plate having a support surface for the tube;
a squeezing roller for squeezing the tube against the support surface;
a roller moving mechanism for sending the fluid in the tube in the direction of roller movement by moving the compression roller along the support surface;
The pump device, wherein the compression plate is provided at the end of the support surface with a relief profile formed by a curved surface continuous with the support surface. 2. The pump device according to claim 1, wherein the support surface and the compression roller are shaped to allow displacement of the tube in the axial direction of the compression roller. The pump device according to claim 1 or 2, wherein the tube is supported in a manner that allows displacement of the support position in the direction in which the tube extends.

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