JP2012189045A - Tube pump - Google Patents

Abstract

PROBLEM TO BE SOLVED: To extend the service life of a tube, and to reduce adverse effect on a fluid to be delivered, in a tube pump.SOLUTION: This tube pump 1 includes: a housing 3 in which cylindrical inner wall surface 21 is formed; a tube 4 arranged in a ring shape; a pressing member 5 pressing the tube 4; an eccentric rotor 6 eccentrically moving the pressing member 5. A pressed part of the tube 4 is moved in one direction by eccentric movement of the pressing member 5 to perform pump action for delivering a fluid in the tube 4. An inner wall surface of the housing 3 is displaceably configured so that a tube maximum pressing amount may be varied, and opens the pressing of the tube 4 after the pump action is started. Since the pressing load imposed on the tube 4 is relieved after the start of the pump action, the damage of the tube 4 is prevented, and adverse effect such as breakage of a constituent molecule included in the fluid in the tube 4 is reduced.

Description

  The present invention relates to a tube pump that performs a pumping action by sequentially pressing the tube.

  Conventionally, a tube arranged in a ring shape along a cylindrical inner wall surface formed in a pump housing is pressed by an eccentric motion of a pressurizing member provided on the inner side of the ring shape to perform a pump action. A tube pump is known (see, for example, Patent Document 1). The pressure member is made of a ring-shaped member, and has a structure that moves eccentrically when the inscribed eccentric rotor is rotated by a motor. Since the tube pump having such a structure compresses the tube indirectly through a ring-shaped pressurizing member, the tube is less damaged and has a longer service life than a structure in which the tube is directly pressed by a roller. It is.

JP 2006-29161 A

  However, in the tube pump as described above, when the fluid in the tube is delivered, the pressurizing member moves while sequentially pressing the tube strongly, so that the tube receives a strong pressing force while being pulled in one direction. Tube damage may still occur. Such tube damage becomes more prominent as the pump operating time is increased. Specifically, the present applicant has confirmed that a tube breaks in an operating time of 500 to 2000 hours in a small tube pump whose pump discharge rate is set to 500 cc to 1000 cc per minute. Therefore, it is extremely difficult to use such a tube pump for a pump application (for example, for computer cooling, fuel cell, etc.) that requires a long life such that the operation time exceeds 50,000 hours. In addition, when the tube pump as described above is used for an artificial dialysis pump, there is a risk that adverse effects such as destruction of components such as red blood cells contained in the blood to be delivered due to compression of the tube may occur.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a tube pump that can extend the life of the tube and can reduce adverse effects on the fluid to be delivered. And

  The tube pump according to the present invention includes a tube disposed in a ring shape along a cylindrical inner wall surface formed in a housing, and is provided inside the ring shape of the tube, and compresses the tube against the inner wall surface. A pressure member, and an eccentric rotor that eccentrically moves the pressure member along the inner wall surface, and the tube is moved in one direction by the eccentric movement of the pressure member. A tube pump for performing a pumping action for delivering a fluid inside, wherein the inner wall surface or the eccentric rotor of the housing is configured to be displaceable so that the maximum tube pressing amount or the maximum eccentric amount can be varied. In addition, after starting the pumping action, the compression of the tube is released.

  In this tube pump, the housing constituting the inner wall surface is composed of at least two arm-shaped members, and one end side of these arm-shaped members is provided rotatably and the other end side is provided openable. Therefore, it is preferable that the cylindrical diameter of the inner wall surface is variable and the maximum pressing amount of the tube is variable.

  In this tube pump, it is preferable that the diameter of the eccentric rotor is gradually different in the axial direction, and the maximum eccentric amount is made variable by the axial movement.

  According to the tube pump of the present invention, after the pump action is started, the compression of the tube is released and the compression load applied to the tube is reduced, so that the tube can be prevented from being damaged and the tube life can be extended. It is possible to reduce adverse effects such as destruction of constituent molecules contained in the fluid inside.

(A) is the top view in the tube compression state before starting a pump action in the tube pump which concerns on the 1st Embodiment of this invention, (b) is the tube compression open state after starting a pump action. Plan view. The AA sectional view taken on the line of Fig.1 (a). BB sectional drawing of Fig.1 (a). (A) is a plan view of the tube pump according to the second embodiment of the present invention with the case cover removed and seen in a tube compression state before starting the pump action, and (b) after starting the pump action. The top view in the tube press release state of. (A) is the sectional view on the AA line of Fig.4 (a), (b) is the sectional view on the AA line of FIG.4 (b). The perspective view which shows the connection structure of the eccentric rotor and motor in the tube pump.

(First embodiment)
A tube pump according to a first embodiment of the present invention will be described with reference to FIGS. In these drawings, the tube pump 1 includes a housing 3 in which a cylindrical chamber 2 is formed, a tube 4, a pressure member 5, an eccentric rotor 6, a motor 7, and a housing 8 to which these are attached. Prepare. The housing 3 is composed of two arm-shaped members 31, 31 that are combined with each other to form one cylindrical chamber 2. The tube 4 is arranged in a ring shape along the inner wall surface 21 of the cylindrical chamber 2, and has a fluid inlet 41 at one end and a fluid outlet 42 at the other end. The pressure member 5 is a ring-shaped member that is provided inside the ring 4 of the tube 4 and presses the tube 4 against the inner wall surface 21. The eccentric rotor 6 is a circular member that is inscribed in the ring-shaped pressure member 5, and causes the pressure member 5 to move eccentrically along the inner wall surface 21. The motor 7 rotates the eccentric rotor 6, and the motor shaft 71 is attached to the eccentric rotor 6 so as to be eccentric from the center of the circle. The casing 8 is plate-shaped here, and is formed of a molded product such as ABS resin.

  The cylindrical chamber 2 is formed in arm-shaped members 31 and 31 as the housing 3, has an inner wall surface 21 that is larger than a semicircumference and smaller than the entire circumference, and a gap portion where the inner wall surface 21 is not formed. This is the outlet for the tube 4. The inner wall surface 21 is freely displaceable by opening and closing the arm-shaped members 31, 31, and a state in which the tube 4 is pressed between the inner wall surface 21 and the pressing member 5 as shown in FIG. As shown in FIG.1 (b), it is set as the structure which can be switched to either of the state which released the compression of the tube 4. FIG. Details of the configuration of the arm-shaped members 31, 31 will be described later.

  The tube 4 is made of a flexible material selected according to the fluid to be delivered, such as rubber or synthetic resin, and is arranged in a ring (ring-opening shape) along the inner wall surface 21 of the cylindrical chamber 2. Both ends (the inlet 41 and the outlet 42) of the tube 4 are extended out of the housing 8 through the gap portion of the cylindrical chamber 2. It is preferable that the vicinity of both ends of the tube 4 is held by the holder 9 so that the tube 4 is not displaced with the eccentric movement of the pressure member 5.

  The pressing member 5 is formed by forming a material having a small friction coefficient into a ring shape having a circular shape in plan view and a constant thickness, and is made of, for example, a fluororesin-based synthetic resin molded product. The pressing member 5 presses and compresses a part of the tube 4 toward the inner wall surface 21 when the eccentric rotor 6 rotates in sliding contact with the inner peripheral surface of the pressing member 5. In the tube 4, the compression portion shown on the left side of each of FIGS. 1A and 2 is closed in the flow path in the tube 4, and the non-compression portion shown on the right side of FIGS. The flow path is secured.

  The motor 7 is a small DC motor and is supplied with power from a DC power source (not shown) outside the tube pump 1. A battery may be built in the tube pump 1 to supply power to the motor 7. Here, the motor 7 is on the opposite side (rear side) of the housing 8 to which the eccentric rotor 6 is attached, and the motor shaft 71 is fixed to the eccentric rotor 6 through the opening 8 a of the housing 8.

  The rotation of the motor 7 is transmitted to the eccentric rotor 6, and the pressing member 5 moves eccentrically by the rotation of the eccentric rotor 6, so that the compressed portion of the tube 4 moves in one direction, and the fluid in the tube 4 moves. Sent out. By such a pump action, the fluid flows into the inflow port 41 and flows out from the outflow port 42.

  In the present embodiment, the cylindrical inner wall surface 21 is configured to be displaceable so that the maximum pressing amount of the tube can be changed, and after starting the pump action, the compression of the tube 4 is released. It has become. That is, the arm-shaped members 31, 31 constituting the inner wall surface 21 are provided such that one end side thereof is rotatably provided on the housing 8 with the shaft 31 a as a fulcrum, and the other end side is provided so as to be opened and closed. The cylindrical diameter of the wall surface 21 is variable, and the maximum tube pressing amount is variable.

  An opening / closing mechanism 10 is provided on the opening / closing end side of the arm-shaped members 31, 31. The opening / closing mechanism 10 includes a rotor piece 12 that is inserted into one elliptical through hole 11 continuously formed across both arm-shaped members 31 and 31 and rotated so as to spread the elliptical through hole 11, and the rotor piece. The motor 13 for rotating 12 is provided. Here, as shown in FIG. 3, the motor 13 is provided on the opposite side of the rotor piece 12 with the housing 8 in between. Further, the opening / closing mechanism 10 includes a spring member 14 that urges the arm-shaped members 31 and 31 in a direction to close each other. The rotor piece 12 has an arc-shaped peripheral wall portion that is at least partially in contact with the peripheral portion on the longitudinal direction side of the elliptical through-hole 11. When the rotor piece 12 is rotated by the motor 13 in the direction of the arrow in the figure when the arm-shaped members 31 and 31 are closed as shown in FIG. The hole 11 is expanded and the arm-shaped members 31, 31 are opened as shown in FIG. When the arm-shaped members 31 are opened, the cylindrical diameter of the inner wall surface 21 is increased, and the relative facing distance between the inner wall surface 21 and the pressure member 5 is increased, so that the maximum tube pressing amount is decreased. Further, when the rotor piece 12 is rotated to the original state, the arm-shaped members 31 and 31 are rotated in the closing direction by the biasing force of the spring member 14, so that the cylindrical diameter of the inner wall surface 21 becomes the original size. Return.

  In the tube pump 1 configured as described above, in an initial state before the fluid is sucked, the arm-shaped members 31 and 31 are closed by the opening / closing mechanism 10, and the tube 4 is interposed between the inner wall surface 21 and the pressurizing member 5. Is in a compressed state (FIG. 1A). When the pressing portion of the tube 4 is moved in one direction by the eccentric movement of the pressure member 5 in such a state, the air in the tube 4 is discharged from the outflow port 42, the inside of the tube 4 is evacuated, and the fluid is Negative pressure is sucked into the inflow port 41. Then, when the pump action for sending out the sucked fluid is started, the arm-shaped members 31 and 31 are opened by the opening / closing mechanism 10 (FIG. 1B). Thereby, since the cylindrical diameter of the inner wall surface 21 is increased, the maximum pressing amount of the tube is reduced and the compression of the tube 4 is released. Even after the compression of the tube 4 is released, the eccentric movement by the pressurizing member 5 is continued, and the tube 4 receives a pressing force moderately suppressed from the pressurizing member 5 so that the fluid in the tube 4 flows. It is discharged from the outlet 42.

  As described above, according to the tube pump 1 according to this embodiment, after the pump action is started, the compression of the tube 4 is released and the compression load applied to the tube 4 is reduced. In addition, adverse effects such as destruction of the constituent molecules contained in the fluid in the tube 4 can be reduced. Moreover, since the load applied to the motor 7 for driving the pump is reduced, the life of the motor 7 is also extended. Further, since the cylindrical diameter of the inner wall surface 21 is variable by opening and closing the two arm-shaped members 31, 31, the maximum tube pressing amount can be easily controlled, and the fluid discharge amount when the tube 4 is released from compression. Easy to adjust.

(Second Embodiment)
A tube pump according to a second embodiment of the present invention will be described with reference to FIGS. 4 and 5, the tube pump 1 of the present embodiment is different from the first embodiment in that the eccentric rotor 6 is configured to be displaceable so that the maximum eccentric amount can be varied. . The same code | symbol is attached | subjected to the location equivalent to 1st Embodiment. The tube pump 1 is accommodated in a housing 8 as a pump case. The housing 8 includes a housing body 81 and a housing cover 82 that covers the housing body 81. The housing body 81 is provided as a pump housing and has a cylindrical inner wall surface 21. The housing body 81 is provided with a groove 81 a for accommodating the tube 4.

  The eccentric rotor 6 has an eccentric taper portion 61 whose diameters are gradually different in the axial direction. The eccentric taper portion 61 is movable in the axial direction with respect to the motor shaft 71, and the maximum eccentricity is obtained by the axial movement. The core amount is variable. The eccentric rotor 6 has a shaft portion 62 at the axial end of the eccentric taper portion 61, and a male screw that engages with a female screw 82 a formed on the housing cover 82 at one end of the shaft portion 62. 62a. The male screw 62a is fed along the axial direction of the female screw 82a by the rotation of the shaft portion 62, so that the axial movement is guided. The shaft portion 62 is integrally formed with the eccentric taper portion 61, and the shaft center of the shaft portion 62 is coaxial with the motor shaft 71.

  The eccentric taper portion 61 has a shape in which the diameter dimension gradually increases toward the axial front end side (housing cover 82 side), and the sliding contact portion with the inner peripheral surface of the pressure member 5 is on the axial front end side. By displacing from the large diameter portion to the small diameter portion on the axial base end side, the maximum eccentricity is reduced. When the maximum eccentric amount is reduced, the relative facing distance between the pressing member 5 and the inner wall surface 21 is increased, and thus the maximum tube pressing amount is reduced. The eccentric taper portion 61 is set to such a size that the compression of the tube 4 is released when the small-diameter portion on the proximal end side in the axial direction is in sliding contact with the inner peripheral surface of the pressure member 5. Here, the inner peripheral surface of the pressure member 5 is a tapered inclined surface along the eccentric taper portion 61.

  In FIG. 6, the connecting portion between the eccentric rotor 6 and the motor 7 has a key coupling structure that allows the eccentric rotor 6 to move in the axial direction. Here, a T-shaped key 71 a is formed at the tip of the motor shaft 71. The eccentric taper portion 61 is formed with a key groove 61a penetrating the key 71a.

  In the tube pump 1 configured as described above, as shown in FIG. 5A, in the initial state before the fluid is sucked, the eccentric rotor 6 has the axial tip end side of the eccentric taper portion 61 added. The tube 4 is slidably contacted with the pressure member 5 and is pressed between the inner wall surface 21 and the pressure member 5. When the eccentric rotor 6 is rotated by the motor 7 in such a state, it is guided to the housing cover 82 side by sliding with the taper inner peripheral surface of the pressure member 5, and the male screw 62a becomes the female screw 82a. The eccentric rotor 6 is screwed and moved in a direction approaching the housing cover 82 side. During this time, the pressing part 5 moves in one direction due to the eccentric movement of the pressure member 5, the air in the tube 4 is discharged from the outlet 42, the inside of the tube 4 is evacuated, and the fluid is negatively applied to the inlet 41. Inhaled by pressure. Then, as shown in FIG. 5B, when the eccentric rotor 6 further moves to the housing cover 82 side and the male screw 62a is disengaged from the female screw 82a, the eccentric rotor 6 The axial movement is stopped, and at this time, the base end side in the axial direction of the eccentric taper portion 61 is in sliding contact with the pressure member 5. At this time, the maximum eccentric amount of the eccentric rotor 6 decreases and the maximum tube pressing amount decreases, so that the compression of the tube 4 is released. Even after the compression of the tube 4 is released, the eccentric movement by the pressurizing member 5 is continued, and the tube 4 receives a pressing force moderately suppressed from the pressurizing member 5 so that the fluid in the tube 4 flows. It is discharged from the outlet 42.

  Also in the tube pump 1 according to the present embodiment, similarly to the first embodiment, damage to the tube 4 can be suppressed, and adverse effects on the fluid in the tube 4 can be reduced. In addition, since the maximum eccentric amount can be varied by moving the eccentric rotor 6 in the axial direction, the maximum tube pressing amount can be easily controlled, and the fluid discharge amount can be adjusted when the tube 4 is released. easy.

  In addition, this invention is not restricted to the structure of the said various embodiment, A various deformation | transformation is possible in the range which does not change the meaning of invention. For example, in the first embodiment, the configuration in which the arm-shaped members 31 and 31 are automatically opened and closed by the opening and closing mechanism 10 after the pump action of the arm-shaped members 31 and 31 is shown, but the present invention is not limited thereto, and the arm-shaped members 31 and 31 can be manually operated. And may be configured to open and close.

DESCRIPTION OF SYMBOLS 1 Tube pump 21 Inner wall surface 3 Housing 31 Arm-shaped member 4 Tube 5 Pressurizing member 6 Eccentric rotor

Claims (3)

A tube disposed in a ring shape along a cylindrical inner wall surface formed in the housing, a pressure member provided inside the ring shape of the tube and compressing the tube against the inner wall surface, A pump that eccentrically moves the pressurizing member along the inner wall surface, and sends the fluid in the tube by moving the compression portion of the tube in one direction by the eccentric motion of the pressurizing member. A tube pump that performs an action,
The inner wall surface or eccentric rotor of the housing is configured to be displaceable so that the maximum pressing amount or maximum eccentric amount of the tube can be varied, and the compression of the tube is released after the pump action is started. A tube pump characterized by   The housing is composed of at least two arm-shaped members, and one end side of these arm-shaped members is rotatably provided, and the other end side is provided to be openable and closable, thereby making the cylindrical diameter of the inner wall surface variable. The tube pump according to claim 1, wherein the maximum tube pressing amount is variable.   2. The tube pump according to claim 1, wherein the eccentric rotor is gradually different in diameter in the axial direction, and the maximum eccentric amount is variable by movement in the axial direction.