Tube pump system and control method therefor

Abstract

To intermittently discharge a fluid delivered from a tube pump to piping by a constant amount.SOLUTION: A tube pump system 700 is provided, including a tube pump 100, piping 200 with a circulation flow channel for causing a fluid delivered from a tube 101 to circulate formed inside, an orifice 400 arranged at a first prescribed position P1, a selector valve 500 arranged at a second prescribed position P2, and a control part 600. The control part 600 controls the tube pump 100 and the selector valve 500 so as to synchronize delivery timing of switching the tube pump 100 from a stop state to a delivery state with circulation flow timing of switching the selector valve 500 from a cut-off state to a circulation flow state, and so as to synchronize stop timing of switching the tube pump 100 from the delivery state to the stop state with cut-off timing of switching the selector valve 500 from the circulation flow state to the cut-off state.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a tube pump system and a control method thereof. [Background technology]

[0002] Conventionally, there is known a tube pump that pumps liquid through a flexible tube by intermittently squeezing the tube with multiple rollers. Since the tube pump pumps pump the liquid intermittently, pulsation (a state in which the flow rate repeatedly increases and decreases) occurs in the pumped liquid. Patent Document 1 discloses a problem in which pulsation occurs when the tube crushed by the rollers returns to its original shape, due to a phenomenon in which liquid is drawn from the downstream flow path to the tube pump. Patent Document 1 discloses that, in order to suppress such pulsation, the pressure of the liquid in the tube that is blocked by contact with the pair of rollers is increased when one of the pair of rollers passes a separation position where it is separated from the tube. According to Patent Document 1, by increasing the pressure of the liquid in the tube, the phenomenon in which the liquid is drawn to the tube pump can be suppressed. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2018-44488 A Summary of the Invention [Problem to be solved by the invention]

[0004] In the field of life sciences, such as medicine and physicochemistry, there are cases where it is required to intermittently discharge (dispense) a fixed amount of liquid as a specimen or sample. In the tube pump system disclosed in Patent Document 1, a pair of drive units that drive a pair of roller units are controlled so that the flow rate of the liquid measured by a flow meter becomes a predetermined target flow rate. The tube pump system disclosed in Patent Document 1 is advantageous in that it can suppress pulsation of the discharged liquid, but is not optimized for applications in which a fixed amount of liquid is intermittently discharged.

[0005] The present invention has been made in consideration of the above circumstances, and aims to provide a tube pump system and a control method thereof that are capable of intermittently ejecting a constant amount of liquid sent from a tube pump to a piping from the piping. [Means for solving the problem]

[0006] In order to solve the above problems, the tube pump system and the control method thereof of the present invention employ the following means. A tube pump system according to one aspect of the present invention includes a tube pump that intermittently compresses a tube made of a flexible material to pump out a liquid in the tube and switch between a pumping state in which the liquid is pumped and a stopped state in which the liquid is not pumped; a pipe having one end connected to the tube and having a circulation flow path formed therein for circulating the liquid pumped out of the tube along a circulation direction from the one end to the other end; a reduced diameter section that is disposed at a first predetermined position between the one end and the other end of the pipe and has a cross-sectional area of ​​a flow path perpendicular to the circulation direction that is the smallest in the circulation flow path; and a reduced diameter section that is disposed at a second predetermined position between the one end and the other end of the pipe and has a flow path that flows through the liquid. a switching valve that switches between a flow state in which liquid passes through the second predetermined position and a blocked state in which flow of liquid is blocked at the second predetermined position, and a control unit that controls the tube pump and the switching valve so that liquid is intermittently discharged from the other end of the piping, wherein the control unit controls the tube pump and the switching valve to synchronize a delivery timing at which the tube pump is switched from the stopped state to the delivery state and a flow timing at which the switching valve is switched from the blocked state to the flow state, and to synchronize a stop timing at which the tube pump is switched from the delivery state to the stopped state and a block timing at which the switching valve is switched from the flow state to the block state.

[0007] According to a tube pump system according to one aspect of the present invention, the tube pump intermittently compresses a tube made of a flexible material, thereby discharging liquid from the tube and directing it to a flow passage formed inside a pipe having one end connected to the tube. A reduced diameter section having a flow passage cross-sectional area that is the smallest in the flow passage is disposed at a first predetermined position of the pipe. Since the flow resistance of the liquid in the reduced diameter section is the largest in the flow passage, the liquid flowing through the flow passage from one end of the pipe to the reduced diameter section is in a state of low dynamic pressure and high static pressure compared to a case in which no reduced diameter section is provided in the flow passage.

[0008] According to a tube pump system according to an aspect of the present invention, the tube pump and the switching valve are controlled to synchronize the delivery timing of the tube pump with the flow timing of the switching valve, and to synchronize the stop timing of the tube pump with the shutoff timing of the switching valve. Since the stop timing of the tube pump and the shutoff timing of the switching valve are synchronized, the discharge of liquid from one end of the piping stops while the static pressure of the liquid between one end of the piping and the second predetermined position where the switching valve is disposed is kept constant.

[0009] In addition, because the delivery timing of the tube pump and the flow timing of the switching valve are synchronized, the discharge of liquid from one end of the piping begins in a state in which the static pressure of the liquid between one end of the piping and the second predetermined position where the switching valve is disposed is held constant. Since the start and stop of the discharge of liquid from the other end of the piping are switched in a state in which the static pressure of the liquid between one end of the piping and the second predetermined position where the switching valve is disposed is held constant, the liquid sent from the tube pump to the piping can be intermittently discharged from the other end of the piping in constant amounts.

[0010] In a tube pump system according to one aspect of the present invention, the tube pump includes a storage section having an inner surface formed in an arc about an axis and on which the tube is arranged, a pair of roller sections that are stored in the storage section and rotate about the axis while blocking the tube from a blocked position about the axis to an unlocked position, and a pair of drive sections that rotate each of the pair of roller sections in the same direction about the axis, and may be configured to include a pressure detection section that detects the pressure of liquid delivered from the tube to the piping, and the control section may be configured to control each of the pair of drive sections so that the fluctuation range of the pressure of the liquid detected by the pressure detection section when the pair of roller sections rotate at least once is within a predetermined value.

[0011] According to the tube pump system of this configuration, the pair of rollers are rotated in the same direction around the axis by the pair of drive units, so that the pair of rollers crush the tube and move from the closed position to the release position. The control unit controls each of the pair of drive units to discharge the liquid that has flowed in from one end of the tube from the other end of the tube. The fluctuation width of the pressure of the liquid detected by the pressure detection unit when the pair of rollers rotate at least once indicates the magnitude of the pulsation of the liquid pumped by the tube pump system. When one of the pair of rollers passes through the release position and the tube crushed by the rollers returns to its original shape, the greater the pressure difference between the pressure of the liquid downstream of the release position and the pressure of the liquid upstream of the release position, the greater the fluctuation width of the pressure. In the tube pump system of this configuration, the control unit controls each of the pair of drive units so that the fluctuation width of the pressure detected by the pressure detection unit is within a predetermined value. Therefore, even if the state of pulsation changes dynamically, the pulsation can be appropriately suppressed in response to the change.

[0012] In the tube pump system having the above configuration, the control unit may be configured to control a first rotation angle about the axis between the pair of roller units when a first roller unit passes through the blocked position and a second rotation angle about the axis between the pair of roller units when a second roller unit passes through the released position, so that the fluctuation range of the pressure detected by the pressure detection unit is within the predetermined value.

[0013] According to the tube pump system of this aspect, the pressure difference between the liquid on the downstream side and the upstream side of the release position depends on the first rotation angle and the second rotation angle. That is, the greater the difference between the first rotation angle and the second rotation angle, the higher the pressure of the liquid in the tube blocked by contact with the pair of rollers, and the smaller the difference between the first rotation angle and the second rotation angle, the lower the pressure of the liquid in the tube blocked by contact with the pair of rollers.

[0014] Therefore, in the tube pump system of this aspect, the control unit controls the first rotation angle about the axis between the pair of rollers when the first roller passes through the closed position and the second rotation angle about the axis between the pair of rollers when the second roller passes through the released position so that the fluctuation range of the pressure detected by the pressure detection unit is within a predetermined value. According to the tube pump system of this aspect, even if the state of pulsation changes dynamically, it is possible to appropriately suppress pulsation in response to the change.

[0015] In a tube pump system according to one embodiment of the present invention, the first predetermined position at which the reduced diameter portion is disposed is located between the one end of the piping and the second predetermined position at which the switching valve is disposed, and the volume of the flow path from the first predetermined position to the second predetermined position of the piping may be 1 / 10 or less of the volume of the piping from the one end to the second predetermined position.

[0016] According to the tube pump system of this configuration, the volume of the distribution flow path from the first predetermined position to the second predetermined position of the piping is 1 / 10 or less of the volume from one end of the piping to the second predetermined position, so that when the tube pump is stopped and the switching valve is in a blocked state, the flow rate of the liquid flowing out from the first predetermined position where the narrowing portion is located to the second position where the switching valve is located can be suppressed. Therefore, it is possible to appropriately suppress a decrease in the pressure of the liquid in the distribution flow path from one end of the piping to the narrowing portion, which is accompanied by a decrease in the flow rate of the liquid intermittently discharged from the piping.

[0017] In a tube pump system according to one embodiment of the present invention, the control unit may be configured to control the tube pump and the switching valve so that the circulation timing is a timing when a first predetermined time has elapsed from the delivery timing, and the shutoff timing is a timing when a second predetermined time has elapsed from the stop timing.

[0018] According to the tube pump system of this configuration, by delaying the flow timing from the discharge timing by a first predetermined time, the tube pump is switched from a stopped state to a flow state to increase the pressure of the liquid held in the piping, and then the switching valve is switched from a blocked state to a flow state, thereby increasing the amount of liquid discharged.

[0019] In addition, by delaying the shutoff timing from the stop timing by the second predetermined time, the switching valve can be switched from the flowing state to the shutoff state without increasing the pressure of the liquid held in the piping by switching the tube pump from the delivery state to the stopped state, thereby reducing the pressure of the liquid in the piping in the shutoff state. Then, by appropriately adjusting the first predetermined time and the second predetermined time, the discharge amount of the intermittently discharged liquid can be adjusted to an appropriate amount.

[0020] In a tube pump system according to one embodiment of the present invention, the control unit may be configured to control the tube pump and the switching valve so that the delivery timing is the timing when a third predetermined time has elapsed from the circulation timing, and the stop timing is the timing when a fourth predetermined time has elapsed from the blocking timing.

[0021] According to the tube pump system of this configuration, by delaying the delivery timing from the circulation timing by a third predetermined time, the switching valve is switched from a blocked state to a circulation state to reduce the pressure of the liquid held in the piping, and then the tube pump is switched from a stopped state to a delivery state, thereby reducing the amount of liquid discharged.

[0022] In addition, by delaying the stop timing from the cutoff timing by a fourth predetermined time, the switching valve is switched from the flow state to the cutoff state to increase the pressure of the liquid held in the piping, and then the tube pump is switched from the delivery state to the stopped state, thereby increasing the pressure of the liquid in the piping in the cutoff state. Then, by appropriately adjusting the third predetermined time and the fourth predetermined time, the discharge amount of the intermittently discharged liquid can be adjusted to an appropriate amount.

[0023] In a control method for a tube pump system according to one aspect of the present invention, the tube pump system includes a tube pump that intermittently compresses a tube made of a flexible material to pump out liquid within the tube and switch between a pumping state in which the liquid is ejected and a stopped state in which the liquid is not pumped out; a pipe having one end connected to the tube and having a circulation flow path formed therein for circulating the liquid pumped out of the tube along a circulation direction from the one end to the other end; a reduced diameter section that is arranged at a first predetermined position between the one end and the other end of the pipe and has a cross-sectional area of ​​a flow path perpendicular to the circulation direction that is the smallest in the circulation flow path; and and a switching valve that is disposed at a second predetermined position between the tube pump and the switching valve and switches between a flow state in which the liquid passes through the second predetermined position and a blocked state in which the flow of the liquid is blocked at the second predetermined position, and the control system further comprises a first control step of controlling the tube pump and the switching valve so as to synchronize a delivery timing at which the tube pump is switched from the stopped state to the delivery state and a flow timing at which the switching valve is switched from the blocked state to the flow state, and a second control step of controlling the tube pump and the switching valve so as to synchronize a stop timing at which the tube pump is switched from the delivery state to the stopped state and a block timing at which the switching valve is switched from the flow state to the block state.

[0024] According to a control method for a tube pump system according to one aspect of the present invention, the tube pump intermittently compresses a tube made of a flexible material, thereby discharging liquid from the tube and directing it to a flow passage formed inside a pipe having one end connected to the tube. A reduced diameter section having a flow passage cross-sectional area that is the smallest in the flow passage is disposed at a first predetermined position of the pipe. Since the flow resistance of the liquid in the reduced diameter section is the largest in the flow passage, the liquid flowing through the flow passage from one end of the pipe to the reduced diameter section is in a state of low dynamic pressure and high static pressure compared to a case in which no reduced diameter section is provided in the flow passage.

[0025] According to a control method for a tube pump system according to one aspect of the present invention, the tube pump and the switching valve are controlled to synchronize the delivery timing of the tube pump with the flow timing of the switching valve, and to synchronize the stop timing of the tube pump with the shutoff timing of the switching valve. Since the stop timing of the tube pump and the shutoff timing of the switching valve are synchronized, the discharge of liquid from one end of the piping is stopped while the static pressure of the liquid between one end of the piping and a second predetermined position where the switching valve is disposed is kept constant.

[0026] In addition, because the delivery timing of the tube pump and the circulation timing of the switching valve are synchronized, the discharge of liquid from one end of the piping begins in a state in which the static pressure of the liquid between one end of the piping and the second predetermined position where the switching valve is disposed is held constant. Since the start and stop of the discharge of liquid from the other end of the piping are switched in a state in which the static pressure of the liquid between one end of the piping and the second predetermined position where the switching valve is disposed is held constant, the liquid sent from the tube pump to the piping can be intermittently discharged from the piping in constant amounts. Effect of the Invention

[0027] According to the present invention, it is an object to provide a tube pump system capable of intermittently discharging a constant amount of liquid sent from a tube pump to a piping from the piping, and a control method thereof. [Brief description of the drawings]

[0028] [Figure 1] 1 is a configuration diagram showing a tube pump system according to a first embodiment of the present invention. [Diagram 2] FIG. 2 is a front view of the tube pump shown in FIG. [Diagram 3] 3 is a vertical cross-sectional view of the tube pump shown in FIG. 2 taken along the line AA. [Figure 4] 11 is a front view showing the tube pump in a state where the first roller portion has reached a closed position. FIG. [Diagram 5] 13 is a front view showing the tube pump in a state where the second roller portion has reached the release position. FIG. [Figure 6] 10 is a flowchart showing a process executed by a control unit so that the tube pump continuously delivers liquid at a constant flow rate. [Figure 7] 10 is a flowchart showing a process executed by a control unit so that a tube pump intermittently delivers liquid at a constant flow rate. [Figure 8] 10 is a flowchart showing a process executed by a control unit so that a tube pump intermittently delivers liquid at a constant flow rate in a tube pump system according to a second embodiment of the present invention. [Figure 9] 13 is a flowchart showing a process executed by a control unit so that a tube pump intermittently delivers liquid at a constant flow rate in a tube pump system according to a third embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0029] [First embodiment] A tube pump system according to a first embodiment of the present invention and a control method thereof will be described below with reference to the drawings. The tube pump system 700 of this embodiment is a device that pumps liquid from an inflow end 701 to an outflow end 702 and intermittently discharges a constant amount of liquid from the outflow end 702. The liquid pumped by the tube pump system 700 of this embodiment is, for example, a liquid used as a specimen or a sample.

[0030] 1, the tube pump system 700 of this embodiment includes a tube pump 100, a pipe 200, a pressure sensor (pressure detection unit) 300, an orifice (diameter-reducing unit) 400, a switching valve 500, and a control unit 600. Each component of the tube pump system 700 of this embodiment will be described below.

[0031] The tube pump 100 is a device that pumps liquid from an inlet end 701 to an outlet end 702. The tube pump 100 pumps liquid by repeatedly moving a roller while compressing a flexible tube 101 with the roller. Liquid discharged from the tube pump 100 into the piping 200 passes through an orifice 400 and a switching valve 500 and reaches the outlet end 702. The tube pump 100 is switched by a control unit 600 between a pumping state in which the liquid is pumped and a stopped state in which the liquid is not pumped. Details of the tube pump 100 will be described later.

[0032] The pipe 200 is a tubular body having one end 200a connected to the tube 101 of the tube pump 100 and having a flow passage formed therein for flowing the liquid discharged from the tube 101 along a flow direction from the one end 200a to the other end 200b. A nozzle 201 is attached to the other end 200b of the pipe 200. The pipe 200 is made of a flexible material (for example, a resin material such as silicone). By appropriately setting the flow passage cross-sectional area of ​​the orifice 400, the pipe 200 can maintain the pressure of the liquid flowing through the flow passage higher than atmospheric pressure.

[0033] 1, a first predetermined position P1 where the orifice 400 is disposed is located between one end 200a of the pipe 200 and a second predetermined position P2 where the switching valve 500 is disposed. The volume of the flow passage from the first predetermined position P1 to the second predetermined position P2 of the pipe 200 is preferably 1 / 10 or less of the volume from the one end 200a of the pipe 200 to the second predetermined position P2.

[0034] When the flow path cross-sectional area of ​​the pipe 200 is the same in other parts except for the orifice 400, it is preferable that the length L3 of the flow path from the first predetermined position P1 to the second predetermined position P2 of the pipe 200 is 1 / 10 or less of the length L2 from one end 200a of the pipe 200 to the second predetermined position P2. The length L2 is the sum of the length L1 from one end 200a of the pipe 200 to the first predetermined position P1 and the length L3.

[0035] The pressure sensor 300 is a device that detects the pressure of the liquid delivered from the tube 101 of the tube pump 100 to the piping 200. The pressure sensor 300 is disposed upstream of the orifice 400 in the flow direction in the piping 200 that guides the liquid from the tube pump 100 to the switching valve 500. The pressure sensor 300 transmits the detected pressure to the control unit 600.

[0036] The orifice 400 is a member that is disposed at a first predetermined position P1 of the flow passage between one end 200a and the other end 200b of the pipe 200, and that has a cross-sectional area of ​​the flow passage perpendicular to the flow direction that is the smallest in the flow passage. The orifice 400 is a member that maximizes the flow resistance of the liquid in the flow passage and increases the static pressure of the liquid in the upstream portion of the pipe 200 in the flow direction from the orifice 400.

[0037] Here, the cross-sectional area of ​​the flow passage of the orifice 400 is desirably set so that the static pressure of the liquid in the upstream portion of the pipe 200 in the flow direction from the orifice 400 is in the range of 20 kPaG or more and 250 kPaG or less. The cross-sectional area of ​​the flow passage of the orifice 400 is particularly desirably set so that it is in the range of 90 kPaG or more and 110 kPaG or less. Here, G means gauge pressure. The cross-sectional area of ​​the flow passage formed by the orifice 400 is set to, for example, in the range of 5% or more and 70% or less of the cross-sectional area of ​​the flow passage of the other portion of the pipe 200.

[0038] The switching valve 500 is a valve body disposed at a second predetermined position P2 between one end 200a and the other end 200b of the pipe 200. The switching valve 500 switches between a flow state in which the liquid passes through the second predetermined position P2 and a blocking state in which the flow of the liquid is blocked at the second predetermined position P2. The switching valve 500 is, for example, a pinch valve that crushes the outer circumferential surface of the flexible pipe 200 to block the fluid flow path.

[0039] The control unit 600 is a device that controls the tube pump 100 and the switching valve 500 so that a constant amount of liquid is intermittently discharged from the other end 200b of the pipe 200. The control unit 600 controls each of a first driving unit 50 and a second driving unit 60 (described later) so that liquid that has flowed in from one end of a flexible tube 101 provided in the tube pump 100 is discharged from the other end of the tube 101.

[0040] As described below, the control unit 600 controls the tube pump 100 and the switching valve 500 so as to synchronize the delivery timing at which the tube pump 100 is switched from a stopped state to a delivery timing at which the switching valve 500 is switched from a blocked state to a flowing state. The control unit 600 also controls the tube pump 100 and the switching valve 500 so as to synchronize the delivery timing at which the tube pump 100 is switched from a sending state to a stopped state to the blocking timing at which the switching valve 500 is switched from the flowing state to a blocked state.

[0041] As shown in FIG. 1, the control unit 600 includes a storage unit 610. The storage unit 610 stores a program executed by the control unit 600. The control unit 600 executes each process described below by reading and executing the program stored in the storage unit 610. The storage unit 610 is configured, for example, by a non-volatile memory in which data can be rewritten. As described below, the control unit 600 adjusts a control waveform for controlling the first driving unit 50 and the second driving unit 60, and stores the adjusted control waveform in the storage unit 610. The control unit 600 can control the first driving unit 50 and the second driving unit 60 using the adjusted control waveform by reading the control waveform stored in the storage unit 610.

[0042] Next, a description will be given of the tube pump 100 provided in the tube pump system 700. Fig. 2 is a front view of the tube pump 100 shown in Fig. 1. Fig. 3 is a vertical cross-sectional view of the tube pump 100 shown in Fig. 2 taken along the line AA.

[0043] As shown in Fig. 2, the tube pump 100 of this embodiment is a device that rotates a first roller portion 10 (first contact member) and a second roller portion 20 (second contact member) in the same direction around an axis X1 (first axis), thereby discharging a fluid in a tube 101 that flows in from an inlet end portion 101a to an outlet end portion 101b. A pipe 200 is connected to the outlet end portion 101b. Note that Fig. 2 shows the tube pump 100 in a state in which the cover 83 shown in Fig. 3 has been removed.

[0044] In the tube pump 100, a tube 101 is arranged in an arc shape around an axis X1 along an inner circumferential surface 82b of a recess 82a of a roller accommodating portion 82 that accommodates the first roller portion 10 and the second roller portion 20. As shown in Fig. 2, the first roller portion 10 and the second roller portion 20 accommodated in the roller accommodating portion 82 rotate around the axis X1 in a counterclockwise rotation direction (the direction indicated by the arrow in Fig. 2) while in contact with the tube 101.

[0045] As shown in FIG. 3, the tube pump 100 of this embodiment includes a first roller unit 10 and a second roller unit 20 that rotate around an axis X1 while in contact with a tube 101, a drive shaft 30 (shaft member) that is arranged on the axis X1 and connected to the first roller unit 10, a drive cylinder (cylinder member) 40 that is connected to the second roller unit 20, a first drive unit 50 that transmits a drive force to the drive shaft 30, a second drive unit 60, and a transmission mechanism 70 (transmission unit) that transmits the drive force of the second drive unit 60 to the drive cylinder 40.

[0046] The first roller unit 10 includes a first roller 11 that rotates about an axis parallel to the axis X1 while in contact with the tube 101, a first roller support member 12 connected to the drive shaft 30 so as to rotate integrally about the axis X1, and a first roller shaft 13 whose both ends are supported by the first roller support member 12 and to which the first roller 11 is rotatably attached.

[0047] The second roller unit 20 has a second roller 21 that rotates around an axis parallel to the axis X1 while in contact with the tube 101, a second roller support member 22 connected to the drive cylinder 40 so as to rotate integrally around the axis X1, and a second roller shaft 23 whose both ends are supported by the second roller support member 22 and to which the second roller 21 is rotatably attached.

[0048] The drive shaft 30 has its lower end connected to the first drive shaft 51 and its upper end inserted into an insertion hole formed in the cover 83. A third bearing member 33 that supports the tip of the first drive shaft 51 rotatably about the axis X1 is inserted into the insertion hole of the cover 83. The drive shaft 30 is supported on the inner peripheral side of the drive cylinder 40 rotatably about the axis X1 by a cylindrical first bearing member 31 inserted along the outer peripheral surface and a cylindrical second bearing member 32 formed independently of the first bearing member 31.

[0049] 3, the first driving unit 50 and the second driving unit 60 are housed inside a casing (housing member) 80. A gear housing section 81 for housing the transmission mechanism 70 and a support member 90 for supporting the first driving unit 50 and the second driving unit 60 are attached inside the casing 80. In addition, a roller housing section 82 for housing the first roller unit 10 and the second roller unit 20 is attached to the upper part of the casing 80.

[0050] The roller accommodating portion 82 has a recess 82a that accommodates the first roller portion 10 and the second roller portion 20. The recess 82a is provided with an inner circumferential surface 82b that is formed in an arc shape about the axis X1. As shown in Fig. 3, the tube 101 is disposed in an arc shape about the axis X1 along the inner circumferential surface 82b.

[0051] The support member 90 is formed with a first through hole extending along the axis X1 and a second through hole 92 extending along the axis X2. The first driving unit 50 is attached to the support member 90 with a fastening bolt (not shown) in a state in which the first driving shaft 51 is inserted into the first through hole 91 formed in the support member 90. Similarly, the second driving unit 60 is attached to the support member 90 with a fastening bolt (not shown) in a state in which the second driving shaft 61 is inserted into the second through hole 92 formed in the support member 90. In this manner, each of the first driving unit 50 and the second driving unit 60 is attached to the support member 90, which is an integrally formed member.

[0052] The first driving unit 50 has a first driving shaft 51, a first electric motor 52, and a first reduction gear 53 that reduces the rotation of a rotating shaft (not shown) rotated by the first electric motor 52 and transmits the reduced rotation to the first driving shaft 51. The first driving unit 50 transmits the driving force of the first electric motor 52 to the first driving shaft 51, thereby rotating the first driving shaft 51 connected to the driving shaft 30 about the axis X1.

[0053] The first roller support member 12 of the first roller unit 10 is connected to the tip end of the drive shaft 30 so as to rotate integrally therewith about the axis X1. The drive force with which the first drive unit 50 rotates the first drive shaft 51 about the axis X1 is transmitted from the first drive shaft 51 to the first roller unit 10 via the drive shaft 30.

[0054] The second driving unit 60 has a second driving shaft 61 arranged on the axis X2, a second electric motor 62, and a second reduction gear 63 that reduces the rotation of a rotating shaft (not shown) rotated by the second electric motor 62 and transmits the rotation to the second driving shaft 61. The second driving unit 60 transmits the driving force of the second electric motor 62 to the second driving shaft 61, thereby rotating the second driving shaft 61 about the axis X2.

[0055] The transmission mechanism 70 has a first gear portion 71 that rotates about an axis X2 (second axis) parallel to the axis X1, and a second gear portion 72 to which the driving force of the second drive shaft 61 is transmitted from the first gear portion 71. The transmission mechanism 70 transmits the driving force of the second drive shaft 61 about the axis X2 to the outer circumferential surface of the drive cylinder 40 to rotate the drive cylinder 40 about the axis X1.

[0056] The second roller support member 22 of the second roller unit 20 is connected to the tip side of the drive tube 40 so as to rotate integrally about the axis X1. The drive force with which the second drive unit 60 rotates the second drive shaft 61 about the axis X2 is transmitted to the outer circumferential surface of the drive tube 40 by the transmission mechanism 70, and then transmitted from the drive tube 40 to the second roller unit 20.

[0057] Next, the discharge of liquid performed by the tube pump system 700 of this embodiment will be described with reference to the drawings. As shown in Fig. 1, the tube pump system 700 of this embodiment detects the pressure of the liquid discharged from the tube pump 100 to the piping 200 by the pressure sensor 300 and transmits it to the control unit 600.

[0058] 1 transmits a control signal for controlling the first drive unit 50 and the second drive unit 60 of the tube pump 100 from a control unit 600 to the tube pump 100. The tube pump 100 may be configured as a device in which the control unit 600 is built in. In this case, the control unit 600 built in the tube pump 100 generates a control signal for controlling the first drive unit 50 and the second drive unit 60, and transmits the control signal to the first drive unit 50 and the second drive unit 60.

[0059] FIG. 4 is a front view showing the tube pump 100 in a state where the first roller unit 10 has reached the blocking position Po1. FIG. 5 is a front view showing the tube pump 100 in a state where the second roller unit 20 has reached the release position Po2. The blocking position Po1 indicates a position around the axis X1 at which the first roller unit 10 and the second roller unit 20 switch from a state where the tube 101 is not blocked to a state where the tube 101 is blocked. The release position Po2 indicates a position around the axis X1 at which the first roller unit 10 and the second roller unit 20 release the state where the tube 101 is blocked to a state where the tube 101 is not blocked. The first roller unit 10 and the second roller unit 20 rotate independently around the axis X1 while blocking the tube 101 between the inner circumferential surface 82b from the blocking position Po1 to the release position Po2.

[0060] 4 and 5 indicate rotation angles around the axis X1, and indicate counterclockwise angles based on the 0° position. The closing position Po1 is, for example, a rotation angle of 50°. The releasing position Po2 is, for example, a rotation angle of 310°.

[0061] The first rotation angle θ1 shown in Fig. 4 is the rotation angle between the first roller unit 10 and the second roller unit 20 about the axis X1 when the first roller unit 10 passes through the closing position Po1. The second rotation angle θ2 shown in Fig. 5 is the rotation angle between the first roller unit 10 and the second roller unit 20 about the axis X1 when the second roller unit 20 passes through the release position Po2.

[0062] Next, there will be described the processing executed by the control unit 600. Fig. 6 is a flow chart showing the processing executed by the control unit 600 so that the tube pump 100 continuously delivers liquid at a constant flow rate.

[0063] When the power is turned on, the control unit 600 sets a target flow rate Ft [ml / min] input by the operator and starts executing each process shown in Fig. 6. The control unit 600 controls the first drive unit 50 and the second drive unit 60 so that the flow rate of the liquid delivered by the tube pump 100 matches the target flow rate Ft [ml / min]. When executing the processes shown in Fig. 6, the control unit 600 controls the switching valve 500 to maintain it in an open state.

[0064] In step S101, the control unit 600 detects the pressure of the liquid flowing through the pipe 200 using the pressure sensor 300. The control unit 600 stores in the memory unit 610 the pressure detected by the pressure sensor 300 when the first roller unit 10 and the second roller unit 20 make at least one rotation (e.g., one rotation, three rotations) around the axis X1.

[0065] In step S102, the control unit 600 refers to the pressure stored in the memory unit 610 and determines whether the pressure fluctuation range ΔP when the first roller unit 10 and the second roller unit 20 rotate at least once around the axis X1 is within a predetermined value Pdif. If the fluctuation range ΔP is not within the predetermined value Pdif, the control unit 600 advances the process to step S103, and if the fluctuation range ΔP is within the predetermined value Pdif, the control unit 600 advances the process to step S105.

[0066] In step S103, since the pressure fluctuation width ΔP is larger than the predetermined value Pdif, the control unit 600 adjusts the first rotation angle θ1 shown in FIG. 4 and the second rotation angle θ2 shown in FIG. 5 in order to reduce the pressure fluctuation width ΔP. The first rotation angle θ1 and the second rotation angle θ2 are adjusted because the pressure difference between the liquid on the downstream side and the upstream side of the release position Po2 corresponds to the first rotation angle θ1 and the second rotation angle θ2. That is, the larger the difference between the first rotation angle θ1 and the second rotation angle θ2, the higher the pressure of the liquid in the tube 101 blocked by contact with the first roller unit 10 and the second roller unit 20 becomes, and the smaller the difference between the first rotation angle θ1 and the second rotation angle θ2, the lower the pressure of the liquid in the tube 101 blocked by contact with the first roller unit 10 and the second roller unit 20 becomes.

[0067] The control unit 600 adjusts the control waveforms for controlling the first drive unit 50 and the second drive unit 60 so that the second rotation angle θ2 is smaller than the first rotation angle θ1. This is to discharge the liquid into the pipe 200 at a pressure higher than the atmospheric pressure, the pressure of the liquid flowing into the tube 101 being substantially the same as the atmospheric pressure. By making the second rotation angle θ2 smaller than the first rotation angle θ1, the pressure of the liquid discharged into the pipe 200 becomes higher than the atmospheric pressure.

[0068] In step S104, the control unit 600 adjusts the angular velocities of the first roller unit 10 and the second roller unit 20 so that the flow rate per unit time of the liquid discharged from the end of the tube 101 to the piping 200 is maintained at a target flow rate Ft (predetermined flow rate). The control unit 600 adjusts the angular velocities of the first roller unit 10 and the second roller unit 20 so that the average angular velocity decreases as the first rotation angle θ1 increases and increases as the first rotation angle θ1 decreases. This is because the amount of liquid blocked inside the tube 101 by the first roller unit 10 and the second roller unit 20 is determined by the first rotation angle θ1.

[0069] The larger the first rotation angle θ1, the larger the amount of liquid blocked by the tube 101, and the smaller the first rotation angle θ1, the smaller the amount of liquid blocked by the tube 101. The control unit 600 maintains the target flow rate Ft (predetermined flow rate) by controlling the angular velocities of the first roller unit 10 and the second roller unit 20 in accordance with the amount of liquid blocked by the tube 101.

[0070] In step S105, the control unit 600 determines whether the operator has instructed to change the target flow rate Ft or to end control, and if YES, ends the process of this flowchart. If NO, the control unit 600 repeats the processes from step S101 onwards.

[0071] The above process shown in Fig. 6 is executed by the control unit 600 so that the tube pump 100 continuously delivers liquid at a constant flow rate. On the other hand, the process shown in Fig. 7 is executed by the control unit 600 so that the tube pump 100 intermittently delivers liquid at a constant flow rate. Fig. 7 is a flowchart showing the process executed by the control unit 600 so that the tube pump 100 intermittently delivers liquid at a constant flow rate.

[0072] In step S201, the control unit 600 controls the first driving unit 50 and the second driving unit 60 to maintain a stopped state so that the tube pump 100 is in a stopped state in which it does not pump out any liquid.

[0073] In step S202, the control unit 600 controls the switching valve 500 to be in a closed state in which the flow of liquid is blocked when the switching valve 500 is in the second predetermined position P2.

[0074] In step S203, the control unit 600 determines whether to start a dispensing operation in which the liquid sent from the tube pump 100 to the piping 200 is intermittently ejected in fixed amounts from the nozzle 201 of the piping 200; if the answer is YES, the process proceeds to step S204; if the answer is NO, the process of this flowchart is terminated.

[0075] In step S204, the control unit 600 controls the first driving unit 50 and the second driving unit 60 to operate so that the tube pump 100 is in a pumping state for pumping liquid. In step S205, the control unit 600 controls the switching valve 500 to be in an open state so that the switching valve 500 is in a flow state in which the liquid flows when the switching valve 500 is in the second predetermined position P2.

[0076] In steps S204 and S205, the control unit 600 synchronizes the delivery timing for switching the tube pump 100 from the stopped state to the delivery state with the flow timing for switching the switching valve 500 from the blocked state to the flow state.

[0077] In step S206, the control unit 600 judges whether the operation period has elapsed from the delivery timing, and if YES, the process proceeds to step S207, and if NO, the determination of step S206 is repeated. The operation period is a time set according to the amount of liquid to be discharged in one dispensing operation from the other end 200b of the pipe 200. The operation period is set, for example, to 0.3 seconds or more and 30 seconds or less.

[0078] In step S207, the control unit 600 switches the first driving unit 50 and the second driving unit 60 from an operating state to a stopped state so as to switch the tube pump 100 from a delivery state to a stopped state. In step S208, the control unit 600 switches the switching valve 500 from the open state to the closed state so as to switch the switching valve 500 from the flow state to the cutoff state.

[0079] In steps S207 and S208, the control unit 600 synchronizes the stop timing for switching the tube pump 100 from the delivery state to the stopped state with the cut-off timing for switching the switching valve 500 from the flow state to the cut-off state by setting the stop timing and the cut-off timing to be the same.

[0080] In step S209, the control unit 600 determines whether or not to end the dispensing operation, and if YES, ends the process of this flowchart, and if NO, proceeds to step S210.

[0081] In step S210, the control unit 600 judges whether the stop period has elapsed since the stop timing, and if YES, the process proceeds to step S204, and if NO, the judgment of step S210 is repeated. The stop period is a time that is preset in the control unit 600 by an input from the operator. The stop period is set to, for example, 1 second or more and 10 seconds or less.

[0082] As described above, the control unit 600 starts discharging liquid from the other end 200b of the pipe 200 by synchronizing the sending timing with the circulation timing, and stops discharging liquid from the other end 200b of the pipe 200 by synchronizing the stop timing with the cutoff timing. The amount of liquid discharged corresponds to the operation period from the sending timing to the stop timing. The control unit 600 controls the tube pump 100 and the switching valve 500 to repeat the operation of discharging a fixed amount of liquid from the other end 200b of the pipe 200 until the dispensing operation is completed.

[0083] According to the tube pump system 700 of the present embodiment described above, the following actions and effects are achieved. According to the tube pump system 700 of this embodiment, the tube pump 100 intermittently compresses the tube 101 formed of a flexible material, whereby the liquid in the tube 101 is discharged and guided to a flow passage formed inside the pipe 200, one end 200a of which is connected to the tube 101. An orifice 400 having a flow passage cross-sectional area that is the smallest in the flow passage is disposed at a first predetermined position P1 of the pipe 200. Since the flow resistance of the liquid in the orifice 400 is the largest in the flow passage, the liquid flowing through the flow passage from one end of the pipe 200 to the orifice 400 has a lower dynamic pressure and a higher static pressure than when the orifice 400 is not provided in the flow passage.

[0084] According to the tube pump system 700 of this embodiment, the tube pump 100 and the switching valve 500 are controlled so as to synchronize the delivery timing of the tube pump 100 with the flow timing of the switching valve, and to synchronize the stop timing of the tube pump 100 with the shutoff timing of the switching valve. Since the stop timing of the tube pump 100 is synchronized with the shutoff timing of the switching valve, the discharge of liquid from the other end 200b of the pipe 200 is stopped while the static pressure of the liquid between one end 200a of the pipe 200 and the second predetermined position P2 where the switching valve 500 is disposed is kept constant.

[0085] In addition, since the delivery timing of the tube pump 100 and the flow timing of the switching valve are synchronized, the discharge of liquid from the other end 200b of the pipe 200 begins in a state in which the static pressure of the liquid between one end 200a of the pipe 200 and the second predetermined position P2 where the switching valve 500 is disposed is kept constant. Since the start and stop of the discharge of liquid from the other end 200b of the pipe 200 are switched in a state in which the static pressure of the liquid between one end 200a of the pipe 200 and the second predetermined position P2 where the switching valve 500 is disposed is kept constant, the liquid sent from the tube pump 100 to the pipe 200 can be intermittently discharged from the other end 200b of the pipe 200 at a constant amount.

[0086] According to the tube pump system 700 of this embodiment, the first roller unit 10 and the second roller unit 20 are rotated in the same direction about the axis X1 by the first drive unit 50 and the second drive unit 60, respectively, so that the first roller unit 10 and the second roller unit 20 move from the closed position Po1 to the released position Po2 while squashing the tube 101. The control unit 600 controls the first drive unit 50 and the second drive unit 60, respectively, to discharge the liquid that has flowed in from the inlet end 101a of the tube 101 from the outlet end 101b of the tube 101.

[0087] The fluctuation width of the pressure of the liquid detected by the pressure sensor 300 when the first roller unit 10 rotates at least once indicates the magnitude of the pulsation of the liquid pumped by the tube pump system 700. When the tube 101, which has been crushed by one of the first roller unit 10 and the second roller unit 20, returns to its original shape after passing through the release position Po2, the greater the pressure difference between the pressure of the liquid downstream of the release position Po2 and the pressure of the liquid upstream of the release position Po2, the greater the fluctuation width of the pressure. In the tube pump system 700 of this embodiment, the control unit 600 controls each of the first drive unit 50 and the second drive unit 60 so that the fluctuation width of the pressure detected by the pressure sensor 300 is within a predetermined value. Therefore, even if the state of the pulsation changes dynamically, the pulsation can be appropriately suppressed in response to the change.

[0088] According to the tube pump system 700 of this embodiment, the volume of the flow passage from the first predetermined position P1 to the second predetermined position P2 of the pipe 200 is 1 / 10 or less of the volume from one end 200a of the pipe 200 to the second predetermined position P2, so that when the tube pump 100 is stopped and the switching valve 500 is in a blocked state, the flow rate of the liquid flowing from the first predetermined position P1 where the orifice 400 is disposed to the second position P2 where the switching valve 500 is disposed can be suppressed. Therefore, it is possible to appropriately suppress a decrease in the flow rate of the liquid intermittently discharged from the pipe 200 caused by a decrease in the pressure of the liquid in the flow passage from one end 200a of the pipe 200 to the orifice 400.

[0089] Second Embodiment Next, a tube pump system 700 according to a second embodiment of the present invention will be described with reference to the drawings. The second embodiment is a modified example of the first embodiment, and is the same as the first embodiment except as otherwise specifically described below, and therefore the description thereof will be omitted.

[0090] The control unit 600 in the first embodiment sets the delivery timing of the tube pump 100 and the flow timing of the switching valve 500 to the same timing, and sets the stop timing of the tube pump 100 and the shutoff timing of the switching valve 500 to the same timing. In contrast, the control unit 600 in the present embodiment sets the flow timing of the switching valve 500 to the timing when a first predetermined time has elapsed since the delivery timing of the tube pump 100, and sets the shutoff timing of the switching valve 500 to the timing when a second predetermined time has elapsed since the stop timing of the tube pump 100.

[0091] 8 is a flowchart showing a process executed by the control unit 600 so that the tube pump 100 intermittently delivers liquid at a constant flow rate in the tube pump system 700 according to the second embodiment of the present invention. The other steps except for step S304A and step S307A in FIG. 8 are the same as the steps in FIG. 7 of the first embodiment, and therefore will not be described below.

[0092] In step S304A, the control unit 600 judges whether or not a first predetermined time has elapsed from the transmission timing, and if YES, the process proceeds to step S305, and if NO, the determination of step S304A is repeated. The first predetermined time is set to, for example, 10 msec or more and 1000 msec or less.

[0093] In step S307A, the control unit 600 judges whether or not a second predetermined time has elapsed since the stop timing, and if YES, the process proceeds to step S308, and if NO, the determination in step S307A is repeated. The second predetermined time is set to, for example, 10 msec or more and 1000 msec or less.

[0094] As described above, the control unit 600 determines the timing when the first predetermined time has elapsed from the delivery timing of the tube pump 100 as the flow timing of the switching valve 500, and determines the timing when the second predetermined time has elapsed from the stop timing of the tube pump 100 as the block timing of the switching valve 500. According to the tube pump system 700 of this embodiment, by delaying the flow timing from the delivery timing by the first predetermined time, the tube pump 100 is switched from the stopped state to the delivery state to increase the pressure of the liquid held in the piping 200, and then the switching valve 500 is switched from the block state to the flow state, thereby increasing the discharge amount of the liquid.

[0095] Furthermore, by delaying the shutoff timing from the stop timing by the second predetermined time, it is possible to switch the switching valve 500 from the flowing state to the shutoff state without increasing the pressure of the liquid held in the piping 200 by switching the tube pump 100 from the delivery state to the stopped state, thereby reducing the pressure of the liquid in the piping 200 in the shutoff state. Then, by appropriately adjusting the first predetermined time and the second predetermined time, it is possible to appropriately adjust the discharge amount of the intermittently discharged liquid.

[0096] Third Embodiment Next, a tube pump system 700 according to a third embodiment of the present invention will be described with reference to the drawings. The third embodiment is a modified example of the first embodiment, and is the same as the first embodiment except where specifically described below, and therefore the description below will be omitted.

[0097] The control unit 600 in the first embodiment sets the delivery timing of the tube pump 100 and the flow timing of the switching valve 500 to the same timing, and sets the stop timing of the tube pump 100 and the shutoff timing of the switching valve 500 to the same timing. In contrast, the control unit 600 in the present embodiment sets the delivery timing of the tube pump 100 to the timing when a third predetermined time has elapsed since the flow timing of the switching valve 500, and sets the stop timing of the tube pump 100 to the timing when a fourth predetermined time has elapsed since the shutoff timing of the switching valve 500.

[0098] Fig. 9 is a flowchart showing a process executed by the control unit 600 so that the tube pump 100 intermittently delivers liquid at a constant flow rate in the tube pump system 700 according to the third embodiment of the present invention. The other steps in Fig. 9 are the same as those in Fig. 7 of the first embodiment, and therefore will not be described below.

[0099] In step S404, the control unit 600 controls the switching valve 500 to be in an open state so that the switching valve 500 is in a flow state in which the liquid flows when the switching valve 500 is in the second predetermined position P2.

[0100] In step S404A, the control unit 600 judges whether or not a third predetermined time has elapsed since the switching timing, and if YES, the process proceeds to step S405, and if NO, the determination in step S404A is repeated. The third predetermined time is set to, for example, 10 msec or more and 1000 msec or less.

[0101] In step S405, the control unit 600 controls the first driving unit 50 and the second driving unit 60 to operate so that the tube pump 100 is in a pumping state for pumping liquid.

[0102] In step S407, the control unit 600 switches the switching valve 500 from the open state to the closed state so as to switch the switching valve 500 from the flow state to the cutoff state.

[0103] In step S407A, the control unit 600 judges whether or not a fourth predetermined time has elapsed since the disconnection timing, and if YES, the process proceeds to step S408, and if NO, the determination of step S407A is repeated. The fourth predetermined time is set to, for example, 10 msec or more and 1000 msec or less.

[0104] In step S408, the control unit 600 switches the first driving unit 50 and the second driving unit 60 from the operating state to the stopped state so that the tube pump 100 switches from the delivery state to the stopped state.

[0105] As described above, the control unit 600 determines the timing when the third predetermined time has elapsed from the flow timing of the switching valve 500 as the delivery timing of the tube pump 100, and determines the timing when the fourth predetermined time has elapsed from the shutoff timing of the switching valve 500 as the stop timing of the tube pump 100. According to the tube pump system 700 of this embodiment, by delaying the delivery timing of the tube pump 100 by the third predetermined time from the flow timing of the switching valve 500, the switching valve 500 is switched from the shutoff state to the flow state to reduce the pressure of the liquid held in the piping 200, and then the tube pump 100 is switched from the stopped state to the delivery state, thereby reducing the discharge amount of the liquid.

[0106] Furthermore, by delaying the stop timing of the tube pump 100 by a fourth predetermined time from the shutoff timing of the switching valve 500, the switching valve 500 is switched from the flow state to the shutoff state to increase the pressure of the liquid held in the piping 200, and then the tube pump 100 is switched from the delivery state to the stopped state, thereby increasing the pressure of the liquid in the piping 200 in the shutoff state. Then, by appropriately adjusting the third predetermined time and the fourth predetermined time, the discharge amount of the intermittently discharged liquid can be adjusted to an appropriate amount.

[0107] Other Embodiments In the above description, the tube pump system 700 is provided with the orifice 400 that minimizes the flow path cross-sectional area in the flow path that guides the liquid from the tube pump 100 to the outflow end 702, but other configurations are also possible. For example, a needle valve that minimizes the flow path cross-sectional area in the flow path that guides the liquid from the tube pump 100 to the outflow end 702 may be provided instead of the orifice 400. The needle valve is capable of changing the flow path cross-sectional area within a predetermined range. [Explanation of symbols]

[0108] 10 First roller section 20 Second roller section 30 Drive shaft 40 Drive tube 50 First Drive Unit 60 Second Drive Unit 70 Transmission Mechanism 80 Casing 90 Support member 100 Tube Pump 101 Tube 101a Inlet end 101b Outflow end 200 Piping 200a one end 200b other end 201 Nozzle 300 Pressure sensor (pressure detection part) 400 Orifice (reduced diameter section) 500 Switching valve 600 Control section 610 Storage section 700 Tube Pump System 701 Inflow end 702 Outlet end Ft Target flow rate P1 1st predetermined position P2 2nd predetermined position Pdif Predetermined Value Po1 blockage position Po2 release position X1,X2 axis ΔP fluctuation range θ1 First rotation angle θ2 Second rotation angle

Claims

1. a tube pump that intermittently compresses a tube made of a flexible material to pump out liquid in the tube and switches between a pumping state in which liquid is pumped and a stopped state in which liquid is not pumped; a pipe having one end connected to the tube and having a flow path formed therein for flowing the liquid discharged from the tube along a flow direction from the one end to the other end; a reduced diameter portion that is disposed at a first predetermined position between the one end and the other end of the pipe, and has a cross-sectional area of ​​a flow path perpendicular to the flow direction that is smallest in the flow path; a switching valve that is disposed at a second predetermined position between the one end and the other end of the pipe and switches between a flow state in which the liquid passes through the second predetermined position and a blocking state in which the flow of the liquid is blocked at the second predetermined position; a control unit that controls the tube pump and the switching valve so that liquid is intermittently discharged from the other end of the pipe, The control unit controls the tube pump and the switching valve to synchronize the delivery timing at which the tube pump is switched from the stopped state to the delivery state with the flow timing at which the switching valve is switched from the blocked state to the flow state, and to synchronize the stop timing at which the tube pump is switched from the delivery state to the stopped state with the block timing at which the switching valve is switched from the flow state to the blocked state.

2. The tube pump comprises: a housing portion having an inner circumferential surface formed in an arc shape about an axis and in which the tube is disposed; a pair of rollers that are accommodated in the accommodation portion and rotate about the axis while occluding the tube from a occluded position about the axis to an released position; a pair of drive units that rotate the pair of roller units in the same direction around the axis line, a pressure detection unit that detects the pressure of the liquid delivered from the tube to the piping; The tube pump system according to claim 1 , wherein the control unit controls each of the pair of drive units so that the fluctuation range of the liquid pressure detected by the pressure detection unit when the pair of roller units rotates at least once is within a predetermined value.

3. The tube pump system of claim 2, wherein the control unit controls a first rotation angle about the axis between the pair of roller units when the first roller unit passes through the blocked position and a second rotation angle about the axis between the pair of roller units when the second roller unit passes through the released position so that the fluctuation range of the pressure detected by the pressure detection unit is within the predetermined value.

4. the first predetermined position where the reduced diameter portion is disposed is located between the one end of the pipe and the second predetermined position where the switching valve is disposed, 4. The tube pump system according to claim 1, wherein the volume of the flow path from the first predetermined position to the second predetermined position of the piping is 1 / 10 or less of the volume of the flow path from the one end of the piping to the second predetermined position.

5. The tube pump system according to any one of claims 1 to 3, wherein the control unit controls the tube pump and the switching valve so that the circulation timing is a timing when a first predetermined time has elapsed from the delivery timing, and the shutoff timing is a timing when a second predetermined time has elapsed from the stop timing.

6. The tube pump system according to any one of claims 1 to 3, wherein the control unit controls the tube pump and the switching valve so that the delivery timing is a timing when a third predetermined time has elapsed from the circulation timing, and the stop timing is a timing when a fourth predetermined time has elapsed from the blocking timing.

7. A method for controlling a tube pump system, comprising: The tube pump system comprises: a tube pump that intermittently compresses a tube made of a flexible material to pump out liquid in the tube and switch between a pumping state in which the liquid is discharged and a stopped state in which the liquid is not pumped; a pipe having one end connected to the tube and having a flow path formed therein for flowing the liquid discharged from the tube along a flow direction from the one end to the other end; a reduced diameter portion that is disposed at a first predetermined position between the one end and the other end of the pipe, and has a cross-sectional area of ​​a flow path perpendicular to the flow direction that is smallest in the flow path; a switching valve that is disposed at a second predetermined position between the one end and the other end of the pipe and switches between a flow state in which the liquid passes through the second predetermined position and a blocking state in which the flow of the liquid is blocked at the second predetermined position, a first control step of controlling the tube pump and the switching valve so as to synchronize a delivery timing at which the tube pump is switched from the stopped state to the delivery state with a flow timing at which the switching valve is switched from the blocked state to the flow state; A control method for a tube pump system comprising: a second control process of controlling the tube pump and the switching valve so as to synchronize a stop timing at which the tube pump is switched from the delivery state to the stopped state and a shutoff timing at which the switching valve is switched from the flow state to the shutoff state.

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