JPH0716059Y2 - Tube pump - Google Patents

Description

[Detailed Description of the Invention] [Industrial field of application] The present invention is directed to a small flow pump used for an analyzer,
More specifically, the present invention relates to a tube pump with a high quantitative accuracy that performs a pumping action by squeezing a tube made of an elastic material.

[Conventional technology]

As a conventional tube pump, for example, the one shown in US Pat. No. 3,737,251 and the drawings is known. In this tube pump, as shown in FIG. 6, an elastic tube 1 is provided around a rotor 2, a roller 4 rotatably held by a roller shaft 3, and a tube having a curved surface and called a shoe 5. It goes through with the guide. When the rotor 2 is driven by the motor 6 to rotate, the roller 4 squeezes the tube 1 to move the fluid in the tube. Reference numeral 7 is a leaf spring, and 8 is an adjusting screw.

Further, in Japanese Utility Model Laid-Open No. 61-198587, the tube holding member is made movable by using a spring, and when used, the tube holding member is pressed toward the fixed tube holding member by the spring. The tube holding member is pulled away from the fixed tube holding member against the tension of the spring, and the tube holding member is temporarily locked in this state to insert the tube between the tube holding member and the fixed tube holding member and the rotating drum, Then, a fluid supply device is described in which the tube holding member is unlocked to hold the tube between the fixed tube holding member and the rotating drum. The lock mechanism is configured such that, when the lock rod comes to the position of the lock hole, the lock rod is pushed by the spring arranged around the lock rod so that the tip of the lock rod fits into the lock hole.

Japanese Utility Model Publication No. 56-45616 discloses a medical device in which a pressing member for pressing an infusion tube and an adjusting screw connecting a supporting member for supporting the pressing member are provided with a spring for preventing loosening around the adjusting screw. An infusion pump is described.

Japanese Utility Model Publication No. 61-198587 and Japanese Utility Model Publication No. 56-45616 disclose tube guides having a curved surface substantially parallel to the locus of the roller.

[Problems to be solved by the device]

When the conventional tube pump as shown in FIG. 6 is used for the quantitative determination of liquid, there is a problem that the quantitative precision is unstable. The reason is as follows.

(1) Since the curvature of the curved surface of the shoe 5 (curvature = 1 / radius of curvature) is smaller than the curvature of the locus of the outer peripheral surface of the roller 4 (the same as the curvature of the outer edge of the rotor 2 in FIG. 6), The distance between the curved surface of the shoe 5 and the position of the roller 4 varies. For example, the distance B is longer than the distance A shown in FIG.

Since the force pressing the tube 1 is affected by the above distance,
When the flow path in the tube 1 is just blocked at the position A, the flow path in the tube 1 is not blocked at the position B.
In FIG. 8, assuming that the tube 1 is blocked between the center of the shoe 5 and the both sides at the angles of θ, the rotor 2 of FIG.
In this state, the flow path in the tube 1 is not blocked and the liquid is leaking.

If the pressure is applied to the liquid in the tube 1 in the direction opposite to the rotation direction of the rotor 2, a part of the liquid sent by the roller 4 moving by an angle of 2θ is pushed backward. Will be returned. Therefore completely tube 1
The final flow rate is the difference between the amount of fluid sent when the internal flow path is blocked and the amount of liquid that leaks due to loose blocking. The amount sent by the roller 4 is stable, but the amount of liquid leaking due to loose blocking varies depending on the pressure applied to the liquid in the tube 1, the viscosity of the liquid, the liquid temperature, and the like. Therefore, the final flow rate becomes an unstable amount.

(2) Since a strong force is applied to the shoe 5, the shoe 5 may not be held stably and the curved surface of the shoe 5 may tilt.
Further, since a strong force is applied to the roller 4, the fixing of the motor 6 may be loosened, or the position of the roller 4 may be slightly displaced due to the shake of the motor shaft. Further, since the elasticity of the tube 1 changes, the angle (8th
The angle 2θ) in the figure may change. The quantitative accuracy becomes unstable due to these mechanical fluctuations.

As described above, in the conventional tube pump shown in FIG.
Since the flow rate fluctuates, the position of the shoe 5 can be moved to adjust the flow rate. For that, the leaf spring 7
The adjustment is performed by the shoe position adjusting mechanism consisting of the adjusting screw 8 and the adjusting screw 8. The adjustment work is performed by operating the pump for a predetermined time to measure the dispensed amount, and adjusting and dispensing until the amount reaches the predetermined amount. It took a lot of time to measure and repeat.

Further, in Japanese Utility Model Laid-Open No. 61-198587 and Japanese Utility Model Publication No. 56-45616, considerable parts are added to fix / unfix the tube guide, and the structure is complicated.
And regarding the concrete configuration of the clamper 17 of the present invention,
Nothing is listed. Also, in the case of Japanese Utility Model Publication No. 56-45616, it is large and requires a space.

In the case of Japanese Utility Model Laid-Open No. 61-198587, when the lock is released, the lock release button is pulled against the spring to pull the lock rod out of the lock hole, and the spring force restores the original state. At this time, since the tube holding member moves abruptly due to the force of the spring at the moment of unlocking, there is a problem in terms of safety, and it may be possible to give an impact to the mechanical portion. If you try to return it slowly, an unreasonable force (moment) will be applied to the unlock button. This is because the pulling direction of the lock release button and the moving direction of the tube holding member are different (perpendicular to each other). In order to return the lock release button slowly without applying excessive force, it is necessary to pull the lock release button while supporting the tube holding member against the force of the spring, resulting in poor operability.

Japanese Utility Model Publication No. 56-45616 describes that a spring is used to prevent the adjustment screw from loosening, but since there are two adjustment screws, it is difficult to make adjustment (to obtain parallelism). If the adjustment is not correct, the pressure applied to the tube will change depending on the location, which causes a problem in quantitative accuracy and stability. In this case, there are two adjusting screws because there is no guide mechanism.

In the case of Japanese Utility Model Laid-Open No. 61-198587, although it has a guide mechanism, it is composed of grooves and bolts and is provided at the lower end of the support member, so it has weak strength and does not react with the tube. There is a risk of tilting due to force.

The present invention has been made in view of the above points, and by simply adding a clamper, it is possible to easily and safely fix and release the tube guide without any impact, and to provide a guide mechanism including a protrusion and a groove. The object of the present invention is to provide a stable tube pump with high quantitative accuracy.

[Means for Solving the Problems]

In order to achieve the above object, the tube pump of the present invention will be described with reference to FIGS. 1 to 5. A rotor 14 for supporting a shaft 13 of a plurality of rollers 12 and a motor 26 for rotating the rotor 26 are provided. A rotor base 22 for mounting the motor, a curved surface substantially parallel to the locus of the roller for arranging the tube on the front surface, and a screw hole 18 for a clamper in the center of the rear surface in the direction of the rotor 14 Tube guide 10 and protrusions on both sides of the tube guide to allow the tube guide to move back and forth only in the direction of the rotor.
15 and 16 and the guide grooves 31 and 32 provided in the rotor base constitute a guide mechanism, which is attached to the rotor base so as to be located behind the tube guide, and the screw hole 18 of the tube guide is formed in the direction of the rotor 14. A spring receiver 33 having a substantially oval clamp hole 41 so as to match, a spring 20 interposed between the tube guide and the spring receiver and pressing the tube guide in the direction of the roller, and passing through the clamp hole 41 of the spring receiver, A central portion 42 having a screw portion 43 screwed into the screw hole 18 of the tube guide, a central member 42 having a substantially oval cross section to be fitted in a clamp hole 41 of a spring receiver, and a clamper 17 provided with a knob portion 44. In a state in which the major axis direction of 42 and the major axis direction of the clamp hole 41 are aligned, the tube guide 10 advances to press the tube, and the major axis direction of the central member 42 The major axis direction and do not match the state of the lamp hole 41 the tube guide 10 is characterized in that so as not to press the not be forward tube.

[Action]

When the pulse motor 26 is rotated, the rotor 14 rotates, and the plurality of rollers 12 move within the curved surface of the tube guide 10 to squeeze the tube 11 and move a certain amount of fluid.

When removing the tube 11, the clamper 17 is operated to the state shown in FIG. 5 and the distance between the roller 12 and the tube guide 10 is widened.

When attaching the tube 11, as shown in FIG. 5, widen the distance between the roller 12 and the tube guide 10 and insert the tube 11 into this distance as shown in FIG. After fixing the tube in the stretched state, the clamper 17 is operated to the state shown in FIG.

〔Example〕

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to FIGS. However, unless otherwise specified, the materials, shapes, relative positions, etc. of the constituent devices described in this embodiment are not intended to limit the scope of the present invention to them only, and are merely descriptions. It's just an example.

The tube guide 10 is similar to the conventional shoe 5 shown in FIG. 6, and its curved surface extends in the longitudinal direction of the tube 11. It is a preferable example that the longitudinal direction of the curved surface has a length such that the three rollers 12 are included in the curved surface so that the roller 12 always blocks the flow path in the tube 11. It is also possible to include two or four or more rollers in the curved surface.

The roller shafts 13 are provided at equal intervals on the same circumference centered on the center of rotation of the rotor 14. In order to make the distance between the roller 12 and the curved surface equal at any position within the curved surface, a curved surface with a radius of curvature centered on the center point is adopted as the curved surface of the tube guide 10. As a result, the distances corresponding to A and B shown in FIG. 7 are equal in this embodiment.

Elongated projections 15 and 16 are laterally provided on both side surfaces of the tube guide 10. As shown in FIG. 2, a screw hole 18 for a clamper 17 and a receiving hole 21 for a spring 20 are provided on the surface of the tube guide 10 opposite to the curved surface. In addition, a Teflon film is coated on the curved surface to protect the tube surface.

As shown in FIG. 1, the rotor base 22 has a shape in which two partitions 24 and 25 are erected on a flat plate 23. At the center of the flat plate 23, a round hole 28 for fitting with the bearing portion 27 of the pulse motor 26 and a motor mounting hole 30 are provided. Guide grooves 31, 32 into which the projections 15, 16 are fitted are provided in parallel with the flat plate at the upper portions of the inner surfaces 24, 25 of both partitions. A screw hole 34 for attaching a spring receiver 33 is provided on the right side surface of both partitions 24 and 25 in FIG. Tube grooves 35 and 36 for holding the tube 11 are provided in the upper portions of both partitions 24 and 25, and the tube 11 is held as shown in FIG.

The rotor 14 is a rotating body fixed to the motor shaft 37, and has a bobbin shape. Roller shaft around the rotor 14
As shown in FIG. 1, 13 is attached in parallel to the rotation axis of the rotor 14 with both ends thereof held by the rotor 14. The roller shaft 13 holds the roller 12. The roller 12 is made of oil-impregnated polyacetal, and is designed to reduce frictional resistance with the roller shaft 13 to smoothen the rotation so that no excessive force is applied to the surface of the tube 11. Also, roller 12
It is also prevented that the shaft hole is worn and the position of the roller 12 is displaced.

The spring receiver 33 receives one end of the spring 20, and has a spring receiving hole 38.
This spring receiver 33 is used to mount the partitions 24, 25 of the rotor base 22.
In order to attach it to both ends of the spring receiver 33,
A stop hole 40 is provided through which a bolt 39, which is coupled to a screw hole 34 provided on the partition, is inserted. An oval clamp hole 41 for the clamper 17 is provided at the center of the spring receiver 33.

The clamper 17 includes a central member 42 having an oval-shaped cross section that fits into the clamp hole 41, and a screw portion that sandwiches the central member from both sides.
43 and a knob portion 44.

As described above, the spring 20 has one end thereof received in the receiving hole 21 provided in the tube guide 10 and the other end received in the spring receiving hole 38 provided in the spring receiver 33. The spring 20 is attached so that the elastic surface thereof causes the curved surface of the tube guide 10 to press the tube 11 against the roller 12 and to cut off the flow path inside the tube 11. The spring constant of the spring 20 is small enough to absorb the positional fluctuation of the roller 12.

FIG. 4 shows a state in which the oval center member 42 of the clamper 17 is fitted in the clamp hole 41. In this state, the spring
The tube guide 10 is pushed to the left in FIG. 4 by the elastic force of 20.

To remove the tube 11, hold the knob part 44 of the clamper 17 against the elastic force of the spring 20 and use the tube guide.
After pulling 10 to the right in FIG. 4, the clamper 17 is rotated by half and the oval center member 42 is hooked on the side surface of the spring receiver 33 as shown in FIG.
The tube so that it does not return to the clamp hole 41 (that is, clamp it) and release the tube. FIG. 5 is a view showing a clamped state, and the tube guide 10 is pulled to the right side of the drawing.

According to the above, the distance between the roller 12 and the tube guide 10 becomes wide, and the tube 11 can be easily attached and detached.

When installing the tube 11, set the tube 11 in the widened part as shown in FIG. 2, and fit the tube 11 into the tube grooves 35 and 36 with the tube 11 slightly stretched, and then fix it. The tube 11 is fixed by adhering the rings 45 and 46 to the tube 11 so that the position of the tube 11 is not displaced. When the fixing of the tube 11 is completed, the clamper 17 is moved in the reverse of the above operation, and the clamp is released to the state shown in FIG.

The rotor 14 is driven by the pulse motor 26 and rotates in the direction of arrow C shown in FIG. The roller 12 rotates while rotating the tube 11 in the direction of the arrow D while keeping the tube 11 in the blocked state. By this operation, the fluid in the tube 11 also moves. This provides a pumping action.

The operation in the direction opposite to the direction of each arrow in FIG. 2 is naturally possible.

The flow rate, flow velocity, flow direction, etc. can be easily changed by adjusting the rotation of the pulse motor 26.

As the tube 11 in the present example, as a result of an experiment using a silicon tube manufactured by Dow Corning, the inner diameter
In the case of a tube having a diameter of 1.3 mm and an outer diameter of 3 mm, a flow rate of 142 μl / sec was obtained by pressing the tube 11 with a weight of 510 g. The spring constant of the spring 20 was 45 gf / mm.

As another embodiment, a tube pump in which liquid is caused to flow in two directions by one rotor may be obtained by further adding a tube guide on the side facing the tube guide 10 of the present embodiment. it can.

For the reasons described below, the tube pump of the present invention can obtain an extremely stable flow rate.

(1) In the conventional shoe, the distance between the curved surface and the surface of the roller is different depending on the position on the curved surface. However, in the tube pump of the present invention, the distance is almost equal over the entire curved surface of the tube guide 10. By making them equal, the interruption of interruption is eliminated.

(2) To prevent the instability of the conventional curved surface holding, the projections 15 and 16 that fit into the guide grooves 31 and 32 are provided on both side surfaces of the tube guide 10 so that the tube guide does not tilt up and down. There is.

(3) The tube is pressed by the force of the spring. This suppresses fluctuations in pressing force and stabilizes the flow rate. In the past, the pressure changed due to the deterioration of the elasticity of the tube, the displacement of the roller and the curved surface of the shoe, and the flow rate also changed, but in the present invention, this change is suppressed by the action of the spring. Conventionally, the above positional deviation was covered only by the tube elasticity, but the elastic constant (force / displacement) of the tube elasticity was very large and could not be covered as compared with the spring.

(4) The motor shaft is fixed by providing a round hole 28 for mounting the motor, and by fitting the motor bearing part, which exerts the most force, into the round hole of the rotor base, the motor shaft is made robust and the fluctuation of the roller position is suppressed. ing.

(5) Teflon coating is applied to the tube contact part of the tube guide, and the roller material is made of oil-impregnated polyacetal to protect the tube from excessive force and to stabilize the flow rate for a long time. .

(6) In the state in which the major axis direction of the central member 42 and the major axis direction of the clamp hole 41 are aligned, the tube guide 10 advances to press the tube, and the major axis direction of the central member 42 and the clamp hole 41.
The tube guide (10) cannot move forward in a state where it does not coincide with the major axis direction of (1) so that the tube is not pressed.

[Effect of device]

Since the tube pump of the present invention is configured as described above, it has the following effects.

(1) The flow rate of the tube pump is stably proportional to the rotation angle of the rotor. Therefore, the quantification accuracy is improved when the quantification is performed by the rotation angle of the rotor.

(2) The stable flow rate eliminates the need for time-consuming and labor-intensive quantitative accuracy check.

(3) Since the clamper is provided, the tube can be easily attached and detached, and the pressure applied to the tube can be kept to zero by clamping when not in use, so that the deterioration of the tube can be suppressed, The life of the tube can be extended.

(4) By providing the clamper for fixing and releasing the fixing of the tube guide, the structure is simplified and the operability and safety are improved.

(5) Since the pulling direction of the clamper and the returning direction of the tube guide are the same, by grasping the knob part of the clamper and pulling it and turning it about 90 degrees, the so-called lock is released and the knob part is grasped as it is and the spring force is applied. In accordance with this, by slowly inserting the central part of the clamper into the clamp hole of the spring receiver, the tube guide can be unlocked easily and safely without impact.
In the opposite case, no problem will occur.

(6) Since it has a guide mechanism consisting of protrusions and grooves,
It is easy to adjust (provide parallelism), the pressure on the tube does not change depending on the location, and it is excellent in terms of quantitative accuracy and stability.

(7) Since the guide mechanism is provided on the side surface of the tube guide and the guide mechanism is composed of the projection and the groove, the strength is sufficient and the tube is not inclined by the reaction force from the tube.

[Brief description of drawings]

FIG. 1 is an exploded perspective view showing an example of the tube pump of the present invention, FIG. 2 is an explanatory view of the same plane (a sectional view shows a section taken along line II-II of FIG. 3), and FIG. FIGS. 4 and 5 are explanatory views around the clamper, FIG. 6 is an explanatory view showing a conventional example of a tube pump, and FIGS. 7 and 8 are explanatory views for explaining problems of the conventional example. Is. 1 ... Tube, 2 ... Rotor, 3 ... Roller axis, 4 ...
… Roller, 5 …… Shoe, 6 …… Motor, 7 …… Flat spring, 8 …… Adjustment screw, 10 …… Tube guide, 11 …… Tube, 12 …… Roller, 13 …… Roller shaft, 14 …… Rotor, 15, 16 ... Protrusion, 17 ... Clamper, 18 ... Screw hole,
20 …… Spring, 21 …… Receiving hole, 22 …… Rotor base,
23 …… Plate, 24, 25 …… Partition, 26 …… Pulse motor, 27
...... Bearing, 28 ...... Round hole, 30 ...... Motor mounting hole, 31, 32
...... Guide groove, 33 …… Spring holder, 34 …… Screw hole,
35, 36 ... Tube groove, 37 ... Motor shaft, 38 ... Spring receiving hole, 39 ... Bolt, 40 ... Stop hole, 41 ... Clamp hole, 42 ... Central member, 43 ... Screw part, 44 …… Knob part, 45,46 …… Rome ring

 ─────────────────────────────────────────────────── ─── Continuation of the front page (56) Bibliography Sho 61-198587 (JP, U) Shoko 56-45616 (JP, Y2)

Claims (1)

[Scope of utility model registration request] 1. A rotor (14) for supporting a shaft (13) of a plurality of rollers (12), a motor (26) for rotating the rotor, a rotor base (22) for mounting the motor, and a tube arranged on the front surface. Therefore, a tube guide (10) having a curved surface substantially parallel to the locus of the roller and having a screw hole (18) for a clamper in the center of the rear surface in the direction of the rotor (14) and a tube guide are installed in the rotor. In order to make it possible to move back and forth only in the direction of the Is attached to the rotor base so as to be located behind the tube guide, and has a substantially oval clamp hole (41) in the direction of the rotor (14) so as to match the screw hole (18) of the tube guide. A spring receiver (33), Interposed between the receiving Yubugaido a spring presses the tube guide in the direction of the roller spring (20)
And a screw part (43) that passes through the clamp hole (41) of the spring receiver and is screwed into the screw hole (18) of the tube guide,
It consists of a central member (42) having a substantially oval cross section that fits into the clamp hole (41) of the spring receiver, and a clamper (17) provided with a knob portion (44). In the state where the major axis direction of the clamp hole (41) is aligned, the tube guide (10) advances to press the tube, and the major axis direction of the central member (42) and the major axis direction of the clamp hole (41) do not match. The tube pump characterized in that the tube guide (10) cannot move forward in this state so as not to press the tube.