JP2010196538A - Tube pump - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To extend the service life of a tube and to reduce the exchange frequencies of the tube, in a tube pump transferring liquid fed from the inlet end of the tube to the outlet end of the tube by causing peristaltic motion of the tube stored between the cylindrical inner peripheral surface of a housing and at least more than one roller revolving along the cylindrical inner peripheral surface in association with the revolving motion of the roller. <P>SOLUTION: A part of the housing is formed with an internal gear along the peripheral direction of the cylindrical inner peripheral surface, and the cylindrical surface of the roller being out of contact with the tube is formed with an external gear engaged with the internal gear and formed in the peripheral direction of the roller so that the roller rotates. The internal gear is not formed in an inlet area where the roller starts contact with the tube and an outlet area where the roller ends contact with the tube on at least the cylindrical inner peripheral surface of the housing. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  According to the present invention, a tube accommodated between a cylindrical inner peripheral surface of a housing and at least one roller revolving along the cylindrical inner peripheral surface is swung along with the revolving motion of the roller. The present invention relates to a tube pump that transfers liquid fed from an inlet end to an outlet end of the tube.

  In order to transfer the liquid at a relatively small flow rate, a tube pump such as that described in Patent Document 1 is used. The tube pump has a housing having a cylindrical inner peripheral surface and a roller that revolves (revolves) along the circumferential direction of the cylindrical inner peripheral surface. The tube is arrange | positioned along the circumferential direction of the cylindrical internal peripheral surface of a housing. When the roller is revolved, the roller moves in the length direction of the tube while crushing the tube. As a result, the tube swings and the liquid in the tube is transferred from the inlet side to the outlet side of the tube.

JP 58-32987

  In a conventional tube pump as shown in Patent Document 1, a roller is supported by an arm fixed to a drive shaft, and the drive shaft is driven to rotate by a motor, whereby the roller circulates along the inner wall of the casing. (Revolution).

  As described above, the roller of the tube pump moves on its outer peripheral surface while crushing the tube. Therefore, the tube is dragged from the inlet side to the outlet side by the frictional force acting between the tube and the roller. For this reason, it is necessary to firmly fix the inlet side end of the tube and the connector so that the inlet side end of the tube does not come off from the connector of the liquid supply source (tank or the like).

  Since the end portion on the inlet side of the tube is fixed to the connector, the tube receives a tensile load in the length direction due to the frictional force acting between the tube and the roller. When this tensile load exceeds the frictional force acting on the tube and the roller, the tensile load is relieved as the roller slides or rolls on the tube. When the roller moves, a frictional force is generated and a tensile load is applied to the tube again. As described above, the tensile load applied to the tube fluctuates periodically, that is, a repeated load is applied to the tube. Therefore, the tube may cause fatigue failure in a relatively short time. For this reason, in the conventional tube pump, it was necessary to replace the tube at a relatively high frequency.

  The present invention has been made to solve the above problems. That is, an object of the present invention is to provide a tube pump having a long tube life and a low frequency of tube replacement.

  In order to achieve the above object, in the tube pump of the present invention, an internal gear is formed in a part of the housing along the circumferential direction of the cylindrical inner peripheral surface, and the roller is not formed on the cylindrical surface of the roller that does not contact the tube. In order to rotate the external gear, an external gear that engages with the internal gear is formed in the circumferential direction, and at least the inlet side region where the roller starts to contact the tube on the cylindrical inner peripheral surface of the housing and the roller finishes contact with the tube An internal gear is not formed in the exit side area.

  Here, the housing may be configured by a plate-like base in which the roller and the tube are arranged on one surface side thereof, and a cap that accommodates the roller and the tube and is attached to the base so as to cover one surface of the base.

  Here, the internal gear is formed in the cap. Alternatively, the internal gear is formed on the base.

  Moreover, it is preferable that the diameter of the pitch circle of the external gear formed on the cylindrical surface of the roller is equal to the diameter of the cylindrical surface in contact with the tube in the roller.

  In the tube pump of the present invention, a roller support member for revolving the roller along the cylindrical inner peripheral surface of the housing is provided in the housing, and the roller is supported on the roller support member so as to be rotatable about its axis. A shaft hole is provided, and the roller bearing hole pivotally supported by the shaft has a step with a large diameter part on the front side and a small diameter part on the back side, and the shaft part of the roller support member is also a large diameter part of the bearing hole. And a stepped shaft that is slidably fitted to each of the small diameter portions.

  Further, it is preferable that the gap between the large diameter portion of the bearing hole and the shaft portion of the roller support member is larger than the gap between the narrow diameter portion of the bearing hole and the shaft portion of the roller support member.

  According to the tube pump of the present invention, when the roller is revolved, the roller is rotated by the engagement between the internal gear provided in the housing and the external gear provided in the roller. For this reason, the roller revolves while rolling on the tube, and the magnitude of the frictional force applied to the tube is reduced. Thereby, the tensile load on the tube caused by the frictional force is also reduced. In addition, when the roller that rotates while the tube is hardly crushed by the roller comes into contact with the tube, the tube is caught in the roller, and a tensile load from the outlet side end to the inlet side end is applied to the tube. In this tube pump, since the internal gear is not formed in the inlet side region where the roller starts contact with the tube and the outlet side region where the roller finishes contact with the tube on the cylindrical inner peripheral surface of the housing, It won't get caught in the rollers. Thus, in the tube pump of the present invention, neither the tensile load due to the frictional force between the tube and the roller nor the tensile load generated when the tube is caught in the roller is generated, so the tube is less likely to be fatigued and destroyed. The lifetime of the tube can be extended. In addition, since the tensile load applied to the tube is small, it is not necessary to firmly fix the inlet end and outlet end of the tube to the connector, and it is easy to incorporate the tube pump into the liquid transport system. It will be something.

FIG. 1 is a front view of a tube pump according to a first embodiment of the present invention. 2 is a cross-sectional view taken along the line II of FIG. 3 is a cross-sectional view taken along the line II-II in FIG. FIG. 4 is a side sectional view of the tube pump according to the second embodiment of the present invention. FIG. 5 is a perspective view showing a roller body and a gear portion of a roller according to a second embodiment of the present invention.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a front view of the tube pump according to the first embodiment of the present invention. 2 is a cross-sectional view taken along the line II of FIG.

  As shown in FIGS. 1 and 2, the tube pump 1 of this embodiment includes a base 10, a cap 20, a pair of rollers 30, a roller support member 40, and a tube 50. The inlet side end 51 of the tube 50 is connected to a liquid supply source (such as a tank) via a connector, and the liquid supplied from the liquid supply source is supplied to the outlet side end 52 of the tube 50 by the tube pump 1. Forwarded to

  The base 10 is a substantially disk-shaped member, and an annular groove 11 (FIG. 2) is formed on one surface 15 (left side in FIG. 2). A protruding portion 31 protruding from the base 10 side end portion (right side in FIG. 2) of the pair of rollers 30 disposed in the cap 20 is inserted into the groove 11. The protrusion 31 is slidable with respect to the annular groove 11, and the groove 11 guides the protrusion 31, so that the roller 30 moves around the groove 11 (revolution). Then, the rotation is limited only to the rotation (rotation) around the axis of the roller 30.

  The cap 20 is a cylindrical member with one end closed so as to be detachably attached to the base 10 so as to cover one surface 15 of the base 10, and an inlet pipe 21 and an outlet pipe 22 are formed on the outer peripheral surface of the cylinder. The tube 50 is disposed along the cylindrical inner peripheral surface 23 of the cap 20, and the inlet side end 51 and the outlet side end 52 thereof are exposed to the outside of the cap 20 through the inlet pipe 21 and the outlet pipe 22. ing.

  As shown in FIG. 2, the roller support member 40 includes a main shaft 41, a pair of arms 42 protruding in the radial direction of the cap 20 in the vicinity of the distal end portion 41 a, and a base end portion of the main shaft 41 from the middle of the arms 42. It has a pair of countershafts 43 protruding in the direction toward 41b (rightward in the figure).

  A through hole 12 is formed in the approximate center of the base 10, and the main shaft 41 is slidably inserted into the through hole 12. In addition, a bearing portion 25 is formed at a substantially center of the inner peripheral bottom surface 24 on the closing side of the cap 20 so that a tip portion 41a (left side in FIG. 2) of the main shaft 41 is slidably inserted. . Both the base end 41b (right side in FIG. 2) side and the tip end 41a side of the main shaft 41 are rotatably held by the through hole 12 of the base 10 and the bearing portion 25 of the cap 20, respectively. It is possible to move.

  A drive shaft of a motor (not shown) is connected to the base end portion 41a of the main shaft 41 via a reduction gear box (not shown) so that the main shaft 41 can be rotated by the motor.

  A bearing hole 32 extending in the axial direction of the roller 30 is formed on the cap 20 side (left side in FIG. 2) of the roller 30, and the auxiliary shaft 43 is slidably inserted into the bearing hole 32, thereby The roller 30 is supported so as to be rotatable with respect to the auxiliary shaft 43.

  Here, the sub-shaft 43 has a large diameter portion 43a on the proximal end side, a small diameter portion 43c on the distal end side, and a medium diameter portion 43b disposed between the large diameter portion 43a and the small diameter portion 43c. It has a cylindrical shape with steps. The bearing hole 32 also has a stepped shape corresponding to the auxiliary shaft 43. Since the base shaft side of the auxiliary shaft 43 has a large diameter and the bending rigidity of the auxiliary shaft 43 is increased, the auxiliary shaft 43 is hardly elastically deformed against the elasticity of the tube 50. For this reason, the roller 30 can press the tube 50 against the cylindrical inner peripheral surface 23 of the cap 20 with a sufficiently large load to crush the tube 50 without leakage.

  On the other hand, the portion having a large diameter in the bearing hole 32 of the roller 30 (that is, the roller 30 is thin) is only the front side portion corresponding to the large diameter portion 43a of the auxiliary shaft 43. The back side of 32 has a small diameter, and the roller 30 at that portion is thick. Thus, the roller 30 of this embodiment is sufficiently thick as a whole, and has sufficient rigidity to withstand the elasticity of the tube 50.

  In the present embodiment, the auxiliary shaft 43 and the bearing hole 32 have a stepped cylindrical shape as described above, but the auxiliary shaft 43 may be a tapered shaft and the bearing hole 32 may be a tapered hole. However, if the countershaft 43 and the bearing hole 32 are tapered, when a radial load is applied to the roller 30 due to the elasticity of the tube 50, a component force in a direction separating the subshaft 43 from the roller 30 is generated. As in the embodiment, it is more desirable that the sub shaft 43 and the bearing hole 32 have a stepped cylindrical shape.

  When the main shaft 41 of the roller support member 40 having the above-described configuration is rotationally driven by an external motor, the roller 30 revolves around the main shaft 41 in a predetermined direction (clockwise direction in FIG. 1). As shown in FIGS. 1 and 2, the roller 30 revolves while pinching and crushing the tube 50 with the cylindrical inner peripheral surface 23 of the cap 20, whereby the tube 50 performs a peristaltic motion. By this peristaltic motion, the liquid in the tube 50 is transferred from the inlet end 51 toward the outlet end 52.

  The tube pump 1 of this embodiment has a mechanism for rotating the roller 30 in order to reduce the frictional force acting between the roller 30 and the tube 50. Hereinafter, the roller rotation mechanism will be described.

  3 is a cross-sectional view taken along the line II-II in FIG. As shown in FIGS. 2 and 3, an external gear 33 is formed on a part of the roller cylindrical surface of the roller 30, and the external gear is formed on a part of the cylindrical inner peripheral surface 23 of the cap 20. A meshing internal gear 26 is formed. When the main shaft 41 of the roller support member 40 is rotated, due to the engagement between the external gear 33 of the roller 30 and the internal gear 26 of the cap 20, the roller 30 revolves in the direction opposite to the revolution direction (see FIG. Rotates counterclockwise (1). Due to this rotation, the roller 30 moves while rolling on the outer peripheral surface of the tube 50, and the frictional force acting between the tube 50 and the roller 30 is greatly reduced.

  In order to make the peripheral speed of the roller cylindrical surface 34 (FIGS. 1 and 2) due to the rotation of the roller 30 equal to the peripheral speed of the roller cylindrical surface 34 due to the revolution of the roller 30, the diameter of the roller cylindrical surface 34 and the external gear 33 The pitch circles 33a have the same diameter. For this reason, the roller 30 rolls on the tube 50 without slipping, and the frictional force acting between them is extremely small.

  The tube pump 1 of the present embodiment has a small frictional force acting between the tube 50 and the roller 30, so that the inlet side end 51 and the outlet side end 52 of the tube 50 are connected to an external connector of the tube pump 1. The tube 50 is moved from the inlet side end 51 side to the outlet side end 52 by the frictional force acting between the roller 30 and the tube 50 without connecting each end to the connector so that it does not come off. The tube 50 is not pulled away from the connector. In addition, since the load applied to the tube 50 is reduced, the tube 50 is not easily damaged by fatigue, and the life of the tube 50 is increased.

  Further, the tube 50 is pulled from the inlet side end portion 51 toward the outlet side end portion 52 by a frictional force acting between the roller 30 and the tube 50. The elastic force of the tube 50 against this tension causes the roller 30 to be pulled by the tube 50. I don't slide up. For this reason, when a plurality of tubes are swung by the roller 30 and the liquid supplied to each tube is transferred, the transfer timing of the liquid in the specific tube is different due to the sliding of the roller 30 and the specific tube. There is no deviation from the liquid transfer timing in the tube. That is, the tube pump 1 of the present embodiment can perform liquid transfer while synchronizing the timing of transfer of liquid supplied to a plurality of tubes.

  Further, as shown in FIGS. 1 and 3, a region α in the vicinity of the inlet tube 21 where the revolving roller 30 starts to contact the tube 50 and a region β in the vicinity of the outlet tube 22 where the contact between the roller 30 and the tube 50 ends are obtained. The internal gear 26 is not formed. When the roller rotates at the positions of the regions α and β, the tube 50 is caught by the rotation of the roller 30 and the tube 50 is pulled from the outlet side end 52 toward the inlet side end 51. In this embodiment, At least in the regions α and β, since the internal gear 26 is not formed on the cylindrical inner peripheral surface 23 of the cap 20, the external gear 33 of the roller 30 does not engage with the internal gear 26 and rotates. Therefore, in this case, in the tube pump 1 of this embodiment, the tube 50 is not caught in the roller 30 at the positions of the regions α and β.

  In the first embodiment of the present invention described above, the internal gear 26 that engages with the external gear 33 of the roller 30 is formed on the cap 20, but the present invention is limited to the above-described configuration. It is not a thing. It is good also as a structure by which an internal gear is provided in the base 10 like the tube pump shown by the 2nd Embodiment of this invention demonstrated below. In the second embodiment as well, the internal gear is not formed on the base 10 at least in the positions of the regions α and β, as in the first embodiment.

  It is a sectional side view (equivalent to II sectional drawing of FIG. 1) of the tube pump 1 'by the 2nd Embodiment of this invention. Note that the tube pump 1 ′ of the present embodiment and the tube pump 1 of the first embodiment are the same except for which of the base and the cap the internal gear is formed and the accompanying roller configuration. is there. Therefore, in the following description, members similar to those of the first embodiment are denoted by the same reference numerals as those of the first embodiment, and detailed description thereof is omitted.

  In the tube pump 1 ′ of this embodiment, a roller 130 for swinging the tube 50 is disposed on the roller body 131 disposed on the cap 20 side (left side in FIG. 4) and on the base 10 side (right side in the diagram). The gear portion 132 is divided. The roller main body 131 and the gear portion 132 are integrally connected by a connecting mechanism described later. When the gear portion 132 meshes with an internal gear provided on the base 10, the entire roller 130 can be rotated about its axis. It can be done.

  The roller main body 131 has a roller cylindrical surface 131 a, and the roller cylindrical surface 131 a crushes the tube 50 with the cylindrical inner peripheral surface 23 of the cap 20. A bearing hole 131b extending toward the base 10 is formed at the end of the roller body 131 on the cap 20 side, and the counter shaft 43 of the roller support member 40 of the tube pump 1 ′ is inserted into the bearing hole 131b. As a result, the roller body 131 is supported so as to be rotatable with respect to the auxiliary shaft 43.

  A circular recess 16 is formed on one surface (left side in the figure) of the base 10. An annular groove 11 is formed on the bottom surface of the recess 16. A protrusion 132 a protruding from the base 10 side end of the gear portion 132 is inserted into the groove 11. The protrusion 132 a is slidable with respect to the groove 11, and the groove 11 guides the protrusion 132 a, so that the movement of the roller 30 is the circular movement (revolution) along the groove 11 and the axis of the roller 130. Limited to surrounding rotation (spinning) only.

  An external gear 132 b is formed on the cylindrical surface of the gear portion 132. An internal gear 16 a is formed on the cylindrical inner peripheral surface of the recess 16 of the base 10. When the main shaft 41 of the roller support member 40 is rotated, the rotational motion is transmitted to the roller 130 and the roller 130 revolves. Then, due to the engagement between the external gear 132b of the gear portion 132 and the internal gear 16a of the base 10, the roller 130 rotates in the direction opposite to the revolution direction as the roller 130 revolves.

  Also in this embodiment, in order to equalize the peripheral speed of the roller cylindrical surface 131a due to the rotation of the roller 130 and the peripheral speed of the roller cylindrical surface 131a due to the revolution of the roller 130, as in the first embodiment, The diameter and the diameter of the pitch circle of the external gear 132b are equal. For this reason, the roller 130 rolls without sliding on the tube 50, and the frictional force acting between the two is extremely small.

  A connection mechanism between the roller main body 131 and the gear portion 132 of the roller 130 will be described below. FIG. 5 is a perspective view showing the base 10 side end portion of the roller body 131 and the cap 20 side end portion of the gear portion 132. As shown in FIG. 5, a cross-shaped connecting hole 131 d extending in the axial direction of the roller body 131 is formed in the end surface 131 c on the base 10 side of the roller body 131. Further, a cross-shaped engagement protrusion 132 d extending in the axial direction of the gear portion 132 is formed on the end surface 132 c of the gear portion 132 on the cap 20 side. Then, by fitting the engaging protrusion 132d into the connecting hole 131d, the roller main body 131 and the gear portion 132 are connected coaxially to form the roller 130.

DESCRIPTION OF SYMBOLS 1, 1 'Tube pump 10 Base 16a Internal gear 20 Cap 23 Cylindrical inner peripheral surface 26 Internal gear 30 Roller 32 Bearing hole 33 External gear 34 Roller cylindrical surface 40 Roller support member 41 Main shaft 42 Arm 43 Sub shaft 43a Thick diameter Part 43b Medium diameter part 43c Small diameter part 50 Tube 130 Roller 131 Roller body 131a Roller cylindrical surface 131b Bearing hole 132 Gear part 132b External gear

Claims (8)

A tube accommodated between the cylindrical inner peripheral surface of the housing and at least one or more rollers revolving along the cylindrical inner peripheral surface is oscillated along with the revolving motion of the roller, whereby the inlet of the tube A tube pump for transferring the liquid fed from the end to the outlet side end of the tube,
An internal gear is formed in a part of the housing along the circumferential direction of the cylindrical inner peripheral surface,
In order to rotate the roller on the cylindrical surface of the roller not in contact with the tube, an external gear engaged with the internal gear is formed in the circumferential direction thereof,
The tube is characterized in that the internal gear is not formed in at least an inlet side region where the roller starts contact with the tube and an outlet side region where the roller ends contact with the tube at least on the inner circumferential surface of the cylinder. pump.   The housing includes a plate-like base on which the roller and the tube are disposed on one surface side thereof, and a cap that accommodates the roller and the tube and is attached to the base so as to cover one surface of the base. The tube pump according to claim 1.   The tube pump according to claim 2, wherein the internal gear is formed on the cap.   The tube pump according to claim 2, wherein the internal gear is formed on the base.   The tube according to any one of claims 1 to 4, wherein a diameter of a pitch circle of an external gear formed on a cylindrical surface of the roller is equal to a diameter of a cylindrical surface in contact with the tube in the roller. pump. A tube accommodated between the cylindrical inner peripheral surface of the housing and at least one or more rollers revolving along the cylindrical inner peripheral surface is oscillated along with the revolving motion of the roller, whereby the inlet of the tube In the tube pump that transfers the liquid fed from the end to the end on the outlet side of the tube,
In the housing, a roller support member for revolving the roller along the cylindrical inner peripheral surface of the housing is provided,
The roller support member is provided with a shaft portion that rotatably supports the roller around its axis,
The bearing hole of the roller that is pivotally supported by the shaft part has a step where the front side is a large diameter part and the back side is a small diameter part,
The tube pump according to claim 1, wherein the shaft portion of the roller support member is also a stepped shaft that is slidably fitted to each of the large diameter portion and the small diameter portion of the bearing hole.   The clearance gap between the large diameter part of the said bearing hole and the axial part of a roller support member is larger than the clearance gap between the narrow diameter part of the said bearing hole, and the axial part of a roller support member. The tube pump described. An internal gear is formed in a part of the housing along the circumferential direction of the cylindrical inner peripheral surface,
In order to rotate the roller on the cylindrical surface of the roller not in contact with the tube, an external gear engaged with the internal gear is formed in the circumferential direction thereof,
The internal gear is not formed in at least an inlet side region where the roller starts contact with the tube and an outlet side region where the roller ends contact with the tube at least on the inner circumferential surface of the cylinder. Item 8. The tube pump according to Item 6 or 7.

Images