JP3637366B2 - Tube pump - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a tube pump in which a tube is arranged in a ring shape along a circular cylindrical chamber, and the tube is sequentially pressed by a pressurizing member provided inside thereof to perform a pump action.
[0002]
[Prior art]
A cylindrical chamber with a circular inner peripheral surface is provided on the substrate, a tube made of an elastic material is arranged in a ring shape along with the inner peripheral surface, and the tube is sequentially pressed in one direction with a rotating roller provided on the inner side, Alternatively, a tube pump that performs a pumping action by moving a closed portion by circularly moving a ring-shaped pressurizing member provided inside the tube along the inner peripheral surface of the cylindrical chamber and sequentially pressing the tube in one direction. Is known. In such a structure, when the pump is stopped, a part of the tube is pressed and closed by the rotating roller and the pressure member, and when the pump is stopped for a long time, the inner surfaces of the tubes of the pressing part stick to each other. As a result, a phenomenon that does not restore the original shape, that is, a so-called sticking phenomenon occurs, and the pumping action cannot be performed.
[0003]
This sticking phenomenon is particularly likely to occur in silicon tubes, and even in fluorine rubber with high chemical resistance, for example, when used for transporting a detergent containing an ether type nonionic surfactant, it takes about 1 to 2 days. In some cases, sticking may occur.
[0004]
[Problems to be solved by the invention]
This invention pays attention to such a problem, and has made it a subject to improve the restoring property of a tube and to prevent a sticking phenomenon.
[0005]
[Means for Solving the Problems]
In order to solve the above-described problem, in the present invention, an adhesive state blocking member is provided inside the tube for separating the inner surfaces of the closed portions generated by the compression after the compression force is removed. As this sticking state blocking member, a thin plate-like string material made of fluororesin that is easily peeled off from the tube is used, and this is inserted into the tube and one or both ends thereof are fixed to the end of the tube. It is constituted by fixing by means such as.
[0006]
Even if such a sticking prevention member is provided, the material of the tube is deformed during compression and the internal flow path is completely closed, so that the pumping action is not hindered. Therefore, the adhesiveness between the inner surfaces of the tubes at the closed portion is relaxed, and a local repulsive force is generated in the tube material around the adhesion state prevention member. For this reason, the resilience when the compression force is removed is improved, and the sticking phenomenon is less likely to occur.
[0007]
DETAILED DESCRIPTION OF THE INVENTION
Next, an embodiment in which the present invention is applied to a tube pump that compresses a tube by circularly moving a ring-shaped pressurizing member along the inner peripheral surface of a cylindrical chamber will be described.
[0008]
In FIG. 1, reference numeral 1 denotes a substrate on which a cylindrical chamber 2 is formed, and an inner peripheral surface 2a of the cylindrical chamber 2 is circular and is formed in a range larger than a semicircular and smaller than a full circumference, and an inner peripheral surface 2a is formed. The part which is not formed becomes the opening 2b. A tube 3 made of an elastic material is arranged in a ring shape along the inner peripheral surface 2a of the cylindrical chamber 2, and both ends thereof are drawn out of the substrate 1 to form an inlet 3a and an outlet 3b. Yes. The substrate 1 is composed of a rubber-based material such as NBR or a synthetic resin molded product such as ABS, and the tube 3 is appropriately selected from rubber-based or various synthetic resin tubes according to the fluid to be transferred. .
[0009]
4 is a ring-shaped pressurizing member disposed inside the tube 3 and has a double structure of an inner ring 41 and an outer ring 42. The inner ring 41 of the pressurizing member 4 is a rigid body having a small friction coefficient. The outer ring 42 is made of an elastic material having a large coefficient of friction, such as rubber. The inner ring 41 and the outer ring 42 have a rectangular cross section and are formed with dimensions that overlap each other. The protrusions provided on the outer peripheral surface 41b of the inner ring 41 are formed in the peripheral grooves provided on the inner peripheral surface 42a of the outer ring 42. By fitting, the outer ring 42 is held by the inner ring 41 so as to be freely rotatable.
[0010]
Reference numeral 5 denotes an eccentric rotor disposed inside the pressurizing member 4, and 6 denotes a rotation shaft to which the eccentric rotor 5 is attached. The tip 5 a of the eccentric rotor 5 is in sliding contact with the inner peripheral surface 41 a of the inner ring 41. The pressure member 4 is rotated to compress the pressure member 4 toward the inner peripheral surface 2 a of the cylindrical chamber 2, and the pressure member 4 is configured to circularly move along the inner peripheral surface 2 a. A motor with a speed reducer for driving the rotary shaft 6 is disposed on the back side of the substrate 1, and a lid is provided on the front side, but these are not shown.
[0011]
The radius of the outer peripheral surface 42 b of the outer ring 42 of the pressure member 4 is selected to be a dimension obtained by subtracting twice or more the wall thickness of the tube 3 from the radius of the cylindrical chamber 2. The sum of the distance from the axis of the rotating shaft 6 to the tip 5a of the eccentric rotor 5 and the dimension from the inner peripheral surface 41a of the inner ring 41 to the outer peripheral surface 42b of the outer ring 42 is added by the tip 5a of the eccentric rotor 5. When the pressure member 4 is pushed to the inner peripheral surface 2a side of the substrate 1, the tube 3 is crushed by the outer ring 42 so that the internal flow path is completely closed.
[0012]
Reference numeral 7 denotes an adhesion state blocking member provided by the present invention, which is inserted into the tube 3 and bent at both ends 7a and 7a, and bonded to the ends of the inlet 3a and outlet 3b of the tube 3, respectively. . The material and dimensions of the adhesion state blocking member 7 are selected according to the tube 3, and specifically, for example, are selected as follows.
[0013]
That is, according to the experiment, when the tube 3 is a rubber tube having an inner diameter of 5 mm, a wall thickness of 1.6 mm, and a hardness Shore A of 60 °, the adhesion state blocking member 7 used for this is fluorine having a thickness of 0.02 mm and a width of 3 mm. resins, for example polytetrafluoroethylene made of thin plate-like ties material strength, peelability was appropriate in terms of chemical resistance.
[0014]
FIG. 2 shows a cross section of a closed portion in which a tube 3 is pressed by a pressure member 4 in a case where a round wire-like adhesion state blocking member is used as a comparative example . In this case, the round line-shaped adhesion state blocking member 7 is hardly deformed, and the tube 3 is pressed and crushed from above and below, and the internal flow path is completely closed. Since the tube 3 is made of material stretched on the upper and lower sides of the adhesive state blocking member 7 and thinned, a strong repulsive force is generated particularly in this portion, and the peelability between the tube 3 and the adhesive state blocking member 7 is increased. In combination with the goodness, the restoration performance when the compression force is removed is improved, and the sticking phenomenon does not occur.
[0015]
FIG. 3 is a cross-sectional view in the case where a compression force is not applied in the present invention in which a thin plate-like string band material is used as the adhesion state blocking member 7. In the case of using the strap material in this way, when the tube 3 is compressed, the adhesive state blocking member 7 is sandwiched between the inner surfaces of the tube, and is necessary for completely closing the internal flow path. The pressing force may be smaller than that in the case of a round line as shown in FIG. Moreover, since the part which the inner surfaces of a tube mutually press-contacted decreases and the adhesiveness of inner surfaces is eased, it becomes easy to improve a recoverability. Furthermore, since the sticking state blocking member 7 has a strip shape, the contact surface with the inner surface of the tube is almost flat and there is no portion where the tube bites strongly, and the tube is not damaged.
[0019]
The illustrated pump is configured as described above. When the eccentric rotor 5 is rotated clockwise as indicated by an arrow to cause the pressure member 4 to move circularly, the tube 3 is blocked by the pressure member 4. Also moves in the clockwise direction, and the fluid inside the tube is discharged from the outlet 3b and simultaneously sucked from the inlet 3a to perform a pumping action.
[0020]
As the pressure member 4 moves circularly, the pressure member 4 rotates counterclockwise.
Since the tube 3 is made of rubber or various synthetic resin materials, and the outer ring 42 is made of an elastic material having a large friction coefficient such as rubber, it is difficult to slip between the tube 3 and the outer ring 42. ing. Therefore, the outer ring 42 in contact with the tube 3 hardly rotates, and slip occurs between the outer ring 42 and the inner ring 41, and only the inner ring 41 rotates. For this reason, almost no pulling force is generated on the tube 3, the tube 3 is pulled and damaged, the load of the driving motor increases, the durability of the pump is impaired, or the inner diameter of the tube 3 changes. As a result, problems such as changes in the discharge amount do not occur.
[0021]
In addition, since the restoring property when the compression force is removed by the adhesion state blocking member 7 according to the present invention is improved, the inner surfaces of the portions of the tube that have been compressed even after the operation is stopped for a long time are mutually connected. The sticking phenomenon of sticking does not occur and the operation can be resumed without any trouble.
[0022]
In addition, although the above-mentioned example is about a tube pump of a system which compresses a tube indirectly with a ring-shaped pressurizing member, this invention can be applied also to a system which compresses a tube directly with a rotating roller. Of course. In particular, in this direct compression method, the diameter of the roller that hits the tube is small, and the sticking force tends to concentrate on the closed part and the sticking phenomenon is likely to occur, so providing a sticky state blocking member to improve the restoring force helps prevent the sticking phenomenon There is a big effect.
[0023]
【The invention's effect】
As is clear from the above description, the tube pump of the present invention is made of a thin plate-like string band made of fluororesin, and is an adhesive state blocking member that separates the tube inner surfaces of the closed portion generated by the compression after the compression force is removed. Is provided inside the tube.
[0024]
Therefore, the adhesion between the inner surfaces of the tubes is eased by the presence of the sticking state blocking member, and at the same time, a local repulsive force is generated in the tube material around the sticking state blocking member, and the compression force is removed. Therefore, even after the operation is stopped for a long time, the operation can be resumed without causing a sticking phenomenon. In addition, since it becomes less necessary to determine the material of the tube in consideration of the sticking phenomenon, the selection of the tube is facilitated.
[0025]
In addition , since a thin strip-like band member is used as the adhesive state blocking member, the portion where the inner surfaces of the tubes are pressed against each other during compression is reduced, and the adhesiveness between the inner surfaces is reduced, so that the resilience is improved. It is easy, and since the sticking state blocking member does not bite into the inner surface of the tube at the time of compression, the inner surface of the tube is not damaged by the sticking state blocking member even in the case of a tube having a low viscosity, for example .
[Brief description of the drawings]
FIG. 1 is a schematic front view of an example of an embodiment of the present invention.
FIG. 2 is a cross-sectional view of the above tube when compressed.
FIG. 3 is a cross-sectional view of the tube when a band-like adhesive state prevention member is used in the above.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Board | substrate 2 Cylindrical chamber 3 Tube 3c Projection 4 Pressurizing member 5 Eccentric rotor 7 Adhesion state prevention member

Claims (1)

A tube made of an elastic material is placed in a ring shape in a cylindrical chamber with a circular inner peripheral surface, and the tube is sequentially pressed in one direction to deliver fluid in the tube. In tube pump,
It is easy to peel off from the tube, does not hinder the flow path blockage inside the tube at the time of compression, and from the thin plate-like string band material made of fluororesin that separates the tube inner surfaces of the blockage part caused by the compression after removing the compression force A tube pump comprising: a sticking state blocking member inserted through the tube.

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