JP2016003860A - Liquid transportation device and liquid transportation method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce fluctuation of a detection value from an encoder in a liquid transportation device driven by rotation of a cam or a rotor.SOLUTION: A liquid transportation device includes a drive mechanism having a rotor when a liquid is transported, an encoder for detecting a rotation angle of the rotor, a comparator circuit for outputting a signal having H level or L level by comparing a detection value detected by the encoder with a prescribed reference value, and a reference value setting part for changing the reference value by detecting the outputted signal.

Description

  The present invention relates to a liquid transport apparatus and a liquid transport method.

  As a liquid transport device for transporting a liquid, a micropump described in Patent Document 1 is known. A plurality of fingers are arranged along the tube in the micro pump, and the tube is squeezed and liquid is transported by the cams pushing the fingers sequentially. In addition, an encoder for measuring the rotation angle of the cam or the rotor that rotationally drives the cam is provided.

JP 2013-24185 A

  In order to perform liquid transportation (liquid feeding) with high accuracy in a liquid transportation device as described in Patent Document 1, it is necessary to detect the rotation angle of the cam with high accuracy by an encoder. For example, when the liquid transport device is used as an insulin infusion device, the operation of feeding the insulin for 3 seconds per minute and stopping the liquid feed for the remaining 57 seconds is repeated. It is necessary to deliver the correct amount of insulin during the second. However, if the liquid feeding operation and the stopping operation are repeated, the cam position may shift due to factors such as external force applied when liquid feeding is stopped, or the detection position may change due to the backlash of the cam rotation mechanism. Thus, the detection value by the encoder fluctuates and an error is likely to occur. In addition, the detection value of the encoder may fluctuate due to the influence of noise or the like. When such fluctuations occur, the actual rotation angle of the cam or rotor becomes unclear, and it becomes difficult to transport an accurate amount of liquid when restarting the liquid feeding operation from the stopped state.

  The present invention has been made in view of such circumstances, and an object of the present invention is to reduce fluctuations in the detected value of an encoder in a liquid transportation device driven by rotation of a rotor.

The main invention of the present invention to solve the above problems is
A drive mechanism having a rotor that rotates when transporting a liquid, an encoder that detects the rotation angle of the rotor, and a detection value detected by the encoder and a predetermined reference value are compared with each other to obtain an H level or an L level. A liquid transport apparatus comprising: a comparator circuit that outputs a signal having a reference value setting unit that detects the output signal and changes the reference value.
Other features of the present invention will become apparent from the description of the present specification and the accompanying drawings.

1 is an overall perspective view of a liquid transport device 1. FIG. 2 is an exploded view of the liquid transport device 1. FIG. 2 is a cross-sectional view of the liquid transport device 1. FIG. 3 is a transparent top view of the inside of the liquid transport apparatus 1. FIG. FIG. 3 is a schematic explanatory diagram of a pump unit 5. 4 is a block diagram for explaining a measurement unit 40 and a control unit 50 of the liquid transport apparatus 1. FIG. It is a figure explaining the various detection parts 40 with which the drive mechanism 12 was equipped. FIG. 6 is an explanatory diagram of a cam side reflecting portion 111 formed on the cam 11. FIG. 6 is an explanatory diagram of a first rotor side reflecting portion and a second rotor side reflecting portion 125 formed on the rotor 122. It is a figure which shows the relationship of signal CAM_Z, ROT_Z, ROT_A, ROT_B. It is a figure explaining the relationship between ROT_A and ROT_B. FIG. 6 is a side view for explaining an operation when detecting a rotation angle of the rotor 122 by the detection unit 40. It is a figure explaining the circuit (encoder circuit 400) which outputs the output signal ROT_A. It is a figure explaining a hysteresis characteristic. FIG. 6 is a diagram for explaining a modification of the encoder circuit 400. It is a figure showing the flow at the time of making the drive mechanism 12 into a drive state from a stop state. It is a figure showing the flow at the time of making the drive mechanism 12 into a stop state from a drive state. It is a figure explaining the power supply control at the time of making the drive mechanism 12 into a drive state from a stop state.

At least the following matters will become apparent from the description of the present specification and the accompanying drawings.
A drive mechanism having a rotor that rotates when transporting a liquid, an encoder that detects the rotation angle of the rotor, and a detection value detected by the encoder and a predetermined reference value are compared with each other to obtain an H level or an L level. A liquid transportation apparatus comprising: a comparator circuit that outputs a signal having a reference value; and a reference value setting unit that detects the output signal and changes the reference value.
According to such a liquid transport apparatus, when the rotation angle of the rotor is detected, fluctuations in the detected value of the encoder can be reduced by the hysteresis characteristic. Since it becomes difficult to accurately detect the rotation angle of the rotor by reducing the fluctuation of the detection value, the operation of the drive mechanism can be controlled with high accuracy. Thereby, a highly accurate liquid transport operation can be realized in the liquid transport device.

In this liquid transport apparatus, the driving mechanism includes a piezoelectric actuator that rotates a rotor that makes a vibrating body that vibrates when a driving signal is applied to the rotor, and the piezoelectric actuator rotates the vibration. It is desirable that the vibration track of the body and the rotating surface of the rotor are biased so that the end of the vibration body and the outer periphery of the rotor are in contact with each other.
According to such a liquid transport device, even when the rotor is urged by the vibrating body in the drive unit, a force is generated in a direction perpendicular to the rotation surface of the rotor, and the optical path length of the rotary encoder varies. , Chattering of the detected value can be suppressed. Therefore, in the liquid transport apparatus that transports the liquid by rotating the rotor by the piezoelectric actuator, the liquid transport operation can be performed with high accuracy.

In such a liquid transport apparatus, comprising a cam that transports liquid by being rotationally driven by the rotation of the rotor, and the drive mechanism has a speed reducing portion that decelerates the rotation of the rotor and transmits it to the cam. It is desirable that the detection unit detects a rotation angle of the speed reduction unit.
According to such a liquid transport device, the rotation angle of the cam can be accurately detected. That is, by detecting the rotation angle of the cam via the speed reducer disposed at a position where the distance from the cam is small and the influence of backlash is small, it is easy to accurately detect the rotation operation of the cam during liquid transportation. In addition, if the speed reduction ratio of the speed reduction part is large, the amount of rotation of the speed reduction part with respect to the amount of rotation of the cam increases, so detecting the rotation angle of the speed reduction part increases the resolution of the cam rotation angle. Can be detected with high accuracy. Therefore, it becomes easy to accurately detect the liquid transport amount when performing the liquid transport operation with the liquid transport device.

The liquid transport apparatus includes a cam that is rotationally driven by the rotation of the rotor and transports the liquid, and the drive mechanism has a speed reduction unit that decelerates the rotation of the rotor and transmits the cam to the cam, and the detection It is preferable that the unit detects a rotation angle of the cam.
According to such a liquid transport device, the rotation angle of the cam can be accurately detected. That is, by directly detecting the rotation angle of the cam by the detection unit provided on the cam, it becomes easy to accurately detect the actual cam operation during liquid transportation. Further, by directly detecting the rotation angle of the cam, it becomes easy to acquire data with little influence of backlash, that is, with less noise. Therefore, it becomes easy to accurately detect the liquid transport amount when performing the liquid transport operation with the liquid transport device.

In such a liquid transport apparatus, when intermittent driving in which the driving mechanism is repeatedly driven and stopped is performed, the level of the signal output when the driving mechanism is stopped is stored, and the driving mechanism is It is desirable to have a resetting unit that applies a resetting voltage having a magnitude corresponding to the stored signal level to a predetermined terminal of the comparator circuit when driving.
According to such a liquid transport device, even when the position of the cam or the rotor is shifted due to an external force or the like while the drive mechanism is stopped, when the drive of the drive mechanism is resumed, The rotation of the cam and the rotor can be controlled in the same state as when the drive is stopped. Thereby, even if it is a case where the intermittent drive which repeats a drive and a stop with a liquid transport apparatus is performed, the liquid transport amount can be controlled accurately.

Detecting a rotation angle of a rotor that rotates when the liquid is transported, comparing a detected value detected with a predetermined reference value, and outputting a signal having an H level or an L level; The method for transporting the liquid is clarified by detecting the output signal and changing the reference value.
According to such a liquid transport method, when the rotation angle of the rotor is detected, fluctuations in the detected value of the rotation angle of the rotor detected by the encoder can be reduced by the hysteresis characteristic. Since it becomes difficult to accurately detect the rotation angle of the rotor by reducing the fluctuation of the detection value, the operation of the drive mechanism can be controlled with high accuracy. Therefore, highly accurate liquid transportation can be realized.

=== Embodiment ===
<Liquid transport device>
FIG. 1 is an overall perspective view of the liquid transport apparatus 1. FIG. 2 is an exploded view of the liquid transport apparatus 1. As shown in the drawing, the side (living body side) to which the liquid transport device 1 is attached may be described as “down” and the opposite side may be described as “up”.

  The liquid transport apparatus 1 is an apparatus for transporting a liquid. The liquid transport apparatus 1 includes a main body 10, a cartridge 20, and a patch 30. The main body 10, the cartridge 20, and the patch 30 are separable as shown in FIG. 2, but are assembled together as shown in FIG. The liquid transport apparatus 1 is suitably used for, for example, attaching a patch 30 to a living body and periodically injecting a liquid (for example, insulin) stored in the cartridge 20. When the liquid stored in the cartridge 20 runs out, the cartridge 20 is replaced, but the main body 10 and the patch 30 are continuously used.

(Pump unit 5)
FIG. 3 is a cross-sectional view of the liquid transport apparatus 1. FIG. 4 is a transparent top view of the inside of the liquid transport apparatus 1, and the configuration of the pump unit 5 is also shown. FIG. 5 is a schematic explanatory diagram of the pump unit 5.

  The pump unit 5 has a function as a pump for transporting the liquid stored in the cartridge 20, and includes a tube 21, a plurality of fingers 22, a cam 11, and a drive mechanism 12.

  The tube 21 is a tube for transporting a liquid. The upstream side of the tube 21 (upstream side when the liquid transport direction is used as a reference) communicates with the liquid storage portion 26 of the cartridge 20. The tube 21 is elastic enough to close when pressed from the finger 22 and return to its original state when the force from the finger 22 is released. The tube 21 is partially arranged in an arc shape along the inner surface of the tube guide wall 25 of the cartridge 20. The arc-shaped portion of the tube 21 is disposed between the inner surface of the tube guide wall 25 and the plurality of fingers 22. The center of the arc of the tube 21 coincides with the rotation center of the cam 11.

  The finger 22 is a member for closing the tube 21. The finger 22 receives the force from the cam 11 and operates in a driven manner. The finger 22 has a rod-shaped shaft portion and a hook-shaped pressing portion, and has a T shape. The rod-shaped shaft portion is in contact with the cam 11, and the hook-shaped pressing portion is in contact with the tube 21. The finger 22 is supported so as to be movable along the axial direction.

  The plurality of fingers 22 are arranged radially from the rotation center of the cam 11 at equal intervals. The plurality of fingers 22 are disposed between the cam 11 and the tube 21. Here, seven fingers 22 are provided.

  The cam 11 has protrusions 11A at a plurality of locations on the outer periphery (four locations in FIG. 5). A plurality of fingers 22 are arranged on the outer periphery of the cam 11, and a tube 21 is arranged outside the fingers 22. When the finger 22 is pressed by the protruding portion 11A of the cam 11, the tube 21 is closed. When the finger 22 is detached from the protrusion 11A, the tube 21 returns to its original shape by the elastic force of the tube 21. When the cam 11 rotates, the seven fingers 22 are sequentially pushed from the protrusion 11A, and the tube 21 is closed sequentially from the upstream side in the transport direction. Thereby, the tube 21 is caused to perform a peristaltic motion, and the liquid filled inside is squeezed into the tube 21 and transported.

(Drive mechanism 12)
The drive mechanism 12 is a mechanism for rotationally driving the cam 11, and includes a piezoelectric actuator 121, a rotor 122, and a deceleration transmission mechanism 123 as shown in FIG.

  The piezoelectric actuator 121 is an actuator for rotating the rotor 122 using the vibration of the piezoelectric element. The piezoelectric actuator 121 vibrates the vibrating body by applying a drive signal to the piezoelectric elements bonded to both surfaces of the rectangular vibrating body. The end of the vibrating body is disposed at a position where it can come into contact with the rotor 122. When the vibrating body vibrates, the end of the vibrating body vibrates along a predetermined orbit such as an elliptical or 8-shaped orbit, and intermittently contacts the rotor 122 in a part of the vibrating orbit, thereby the rotor 122. Is driven to rotate. The piezoelectric actuator 121 is urged toward the rotor 122 by a pair of springs (spring members) so that the end of the vibrating body contacts the rotor 122. That is, the end of the vibrating body and the outer periphery of the rotor 122 are biased so that the vibration trajectory of the vibrating body and the rotating surface of the rotor 122 are parallel to each other.

  The rotor 122 is a driven body that is rotated by the piezoelectric actuator 121. The rotor 122 is formed with a rotor pinion that constitutes a part of the deceleration transmission mechanism 123.

  The reduction transmission mechanism 123 is a mechanism that transmits the rotation of the rotor 122 to the cam 11 at a predetermined reduction ratio. The deceleration transmission mechanism 123 includes a rotor pinion, a transmission wheel 123A, and a cam gear (see FIG. 7). The rotor pinion is a small gear that is integrally attached to the rotor 122. The transmission wheel 123 </ b> A has a large gear that meshes with the rotor pinion and a pinion that meshes with the cam gear, and has a function of transmitting the rotational force of the rotor 122 to the cam 11. The cam gear is integrally attached to the cam 11 and is rotatably supported together with the cam 11. Here, the reduction ratio of the speed reduction transmission mechanism 123 is 40. That is, when the rotor 122 rotates once, the cam 11 rotates 1/40.

  Of the tube 21, the plurality of fingers 22, the cam 11, and the drive mechanism 12 constituting the pump unit 5, the cam 11 and the drive mechanism 12 are provided in the main body 10, and the tube 21 and the plurality of fingers 22 are the cartridge 20. Is provided. The main body 10 is also provided with a detection unit 40 for measuring the rotation angle of the cam 11, etc., a control unit 50 for controlling the piezoelectric actuator 121, etc., and a battery 19 for supplying electric power to the piezoelectric actuator 121, etc.

(Detection unit 40 / control unit 50)
FIG. 6 is a block diagram for explaining the detection unit 40 and the control unit 50 of the liquid transport apparatus 1. FIG. 7 is a diagram illustrating various detection units 40 provided in the drive mechanism 12.

  The detection unit 40 includes a cam rotation detection unit 41 for detecting the rotation state of the cam 11, a first rotor rotation angle detection unit 43, and a second rotor rotation angle detection unit 44 for detecting the rotation state of the rotor 22. And a rotor rotation detector 45. Here, the “rotation state” of the cam 11 or the rotor 22 is a rotation amount from the rotation reference position set for each, and is detected as the rotation angle of the cam 11 or the rotor 22.

  The cam rotation detection unit 41 is a rotary encoder provided with a photo reflector including a light emitting unit 41A and a light receiving unit 41B. The light emitting unit 41A is a light source that emits light for detecting the rotation angle of the detection target (here, the cam 11). For example, a light emitting diode is used. The light receiving unit 41B is a light receiving unit that receives light reflected from the detection target after being emitted from the light emitting unit 41A. For example, a photodiode is used. In the present embodiment, a cam-side reflecting portion 111 is formed on the cam 11, the cam-side reflecting portion 111 reflects light from the light emitting portion 41A, and the light receiving portion 41B receives the reflected light. FIG. 8 is an explanatory diagram of the cam-side reflecting portion 111 formed on the cam 11. As shown in FIG. 8, one cam side reflection portion 111 is formed in the gear portion of the cam 11. In addition, the positional relationship with respect to the protrusion part 11A of the cam side reflection part 111 changes for every product. The light receiving unit 41B outputs a voltage signal corresponding to the amount of received light, and the detection unit 40 (cam rotation detection unit 41) outputs an output signal CAM_Z having an H level and an L level to the control unit 50 based on the magnitude of the voltage signal. Output.

  The first rotor rotation angle detection unit 43 is a rotary encoder that includes a light emitting unit 43A and a light receiving unit 43B, and the second rotor rotation angle detection unit 44 is a rotary type that includes a light emitting unit 44A and a light receiving unit 44B. It is an encoder. These have substantially the same structure as the cam rotation detection unit 41. The rotor rotation detection unit 45 is also a similar rotary encoder, and includes a light emitting unit 45A and a light receiving unit 45B. The first rotor rotation angle detection unit 43 and the second rotor rotation angle detection unit 44 are arranged at positions shifted by a predetermined rotation angle with respect to the rotation direction of the rotor 122 (see FIG. 7).

  The rotor 122 is formed with a first rotor side reflecting portion 124 and a second rotor side reflecting portion 125. FIG. 9 is an explanatory diagram of the first rotor side reflecting portion 124 and the second rotor side reflecting portion 125 formed on the rotor 122. As shown in FIG. 9, the rotor 122 has twelve first rotor-side reflecting portions 124, and each reflecting portion is radially arranged at equal distances and equal intervals around the rotation axis of the rotor 122. Has been. That is, the angle between two adjacent first rotor-side reflecting portions 124 is 30 degrees. Light emitted from the light emitting unit 43A of the first rotor rotation angle detecting unit 43 and the light emitting unit 44A of the second rotor rotation angle detecting unit 44 is reflected by the first rotor side reflecting unit 124, and is received by the light receiving units 43B and 44B. Each is received. The light receiving units 43B and 44B output voltage signals corresponding to the amount of received light, and the detection unit 40 outputs ROT_A and ROT_B having H level and L level to the control unit 50 based on the magnitudes of the voltage signals, respectively. . One second rotor side reflecting portion 125 is formed on the inner side of the first rotor side reflecting portion 124, that is, on the rotating shaft side of the rotor 22. The light emitted from the light emitting unit 45A of the rotor rotation detecting unit 45 is reflected by the second rotor side reflecting unit 125 and received by the light receiving unit 45B. The light receiving unit 45B outputs a voltage signal corresponding to the amount of received light, and the detection unit 40 outputs an output signal ROT_Z having an H level and an L level to the control unit 50 based on the magnitude of the voltage signal.

  The cam rotation detection unit 41, the first rotor rotation angle detection unit 43, the second rotor rotation angle detection unit 44, and the rotor rotation detection unit 45 are limited to reflective optical sensors (so-called photo reflectors). Instead, a transmissive optical sensor may be used.

  As illustrated in FIG. 6, the control unit 50 includes a counter 51, a storage unit 52, a calculation unit 53, and a driver 54. The counter 51 counts the number of edges included in the output signal ROT_A of the first rotor rotation angle detector 43 and the output signal ROT_B of the second rotor rotation angle detector 44. The count value of the counter 51 indicates the rotation angle of the rotor 122. Since the rotation angle of the rotor 122 corresponds to the rotation angle of the cam 11, the count value of the counter 51 also indicates the rotation angle of the cam 11. Further, the storage unit 52 stores a program for the calculation unit 53 to drive the driver 54, and stores a position on the output signal ROT_A (ROT_B) corresponding to the pump origin. The calculation unit 53 executes the program stored in the storage unit 52 and based on the count value of the counter 51 (the rotation angle of the cam 11 and the rotor 122) and the position on the output signal ROT_A (ROT_B) corresponding to the pump origin. Thus, the displacement between the position of the rotor 122 and the cam 11 relative to the pump origin at the time when the pump unit 5 was stopped and the position of the rotor 122 and the cam 11 relative to the pump origin at the present time was calculated, and a deviation occurred. In this case, the driver 54 is driven so as to reduce the influence of the shift. The driver 54 outputs a drive signal to the piezoelectric actuator 121 of the drive mechanism 12 in accordance with an instruction from the calculation unit 53. The counter 51 counts edges included in the output signal CAM_Z of the cam rotation detection unit 41 and the output signal ROT_Z of the rotor rotation detection unit 45, and detects the rotation speeds of the cam 11 and the rotor 122.

  FIG. 10 is a diagram illustrating the relationship between the output signals CAM_Z, ROT_Z, ROT_A, and ROT_B. As described above, the first rotor rotation angle detector 43 outputs the output signal ROT_A according to the amount of reflected light received by the light receiver 43B. In the present embodiment, as shown in FIG. 9, twelve first rotor-side reflecting portions 124 are formed in the circumferential direction of the rotor 122, so that each time the rotor 122 makes one rotation, the first rotor rotation angle is detected. The unit 43 outputs a signal ROT_A including 12 pulse waveforms. Similarly, the second rotor rotation angle detector 44 outputs a signal ROT_B including 12 pulse waveforms.

  Further, the rotor rotation detection unit 45 outputs an output signal ROT_Z in accordance with the amount of reflected light received by the light receiving unit 45B. As shown in FIG. 9, since one second rotor-side reflecting portion 125 is formed in the circumferential direction of the rotor 122, each time the rotor 122 makes one rotation, the rotor rotation detection unit 45 has one piece. A signal ROT_Z including a pulse waveform is output.

  The cam rotation detection unit 41 outputs an output signal CAM_Z according to the amount of reflected light received by the light receiving unit 41B. As shown in FIG. 8, since one cam-side reflecting portion 111 is formed in the circumferential direction of the cam 11, each time the cam 11 makes one rotation, the cam rotation detecting portion 41 has one pulse shape. A signal CAM_Z including a waveform is output.

  As described above, since the rotor 122 rotates 40 times while the cam 11 rotates once, the output of the first rotor rotation angle detector 43 corresponding to the rotor 122 in one cycle of the output signal CAM_Z of the cam rotation detector 41. The number of pulses included in the signal ROT_A is 40 × 12 = 480. Therefore, if the rise and fall of the pulse in the signal ROT_A are each counted as 1 count, 960 counts from 0 to 959 per rotation of the cam 11 are measured as shown in FIG.

  Further, by using the relationship between the output signals CAM_Z and ROT_Z and the output signal ROT_A, the control unit 50 can specify the rotation reference position of the cam 11 (rotor 122). Here, the rotation reference position is a position serving as a reference when the rotation angle of the cam 11 or the rotor 122 is detected. By detecting the movement amount from the rotation reference position, the control unit 50 can calculate the rotation angle (rotation amount) of the cam 11 or the rotor 122.

  Although details will be described later, in the drive mechanism 12 of the present embodiment, the drive state and the stop state are repeated (intermittent drive). Therefore, when the stopped cam 11 (rotor 122) is re-driven, the deceleration transmission mechanism The rotation reference position of the cam 11 (rotor 122) may be shifted by about one to two pulses of the output signal ROT_A (output signal ROT_B) from the rotation reference position at the time of stoppage due to the influence of 123 backlash, external force, or the like. . In such a case, by correcting the rotation reference position of the cam 11 (rotor 122) by the shifted pulse, the subsequent rotation control of the cam 11 (rotor 122) can be accurately performed. For example, when the drive mechanism 12 is re-driven from the stopped state, the control unit 50 counts the number of pulses of the output signal ROT_A (output signal ROT_B) included in one cycle of the output signal CAM_Z or the output signal ROT_Z. If the output signal ROT_A included in one rotation of the cam 11 is less than 960 pulses by one pulse, correction is performed so as to set a position one pulse less than the original rotation reference position as a new rotation reference position. . Conversely, if there is more than one pulse, a position that is one pulse more than the original rotation reference position is set as a new rotation reference position.

  Further, the control unit 50 can detect whether the rotation direction of the rotor 122 or the like has shifted in the normal rotation direction or the reverse rotation direction from the relationship between the output signals ROT_A and ROT_B. That is, the direction in which the drive mechanism 12 has rotated is determined depending on whether the level of the output signal ROT_B detected when the level of the output signal ROT_A changes is the H level or the L level. FIG. 11 is a diagram for explaining the relationship between ROT_A and ROT_B. As shown in FIG. 7, the first rotor rotation angle detection unit 43 and the second rotor rotation angle detection unit 44 are arranged at positions shifted by a predetermined amount with respect to the rotation direction of the rotor 122. Therefore, among the 12 first rotor-side reflection units 124 provided, the output signals ROT_A and ROT_B output by the light reflected by a certain reflection unit have a predetermined phase difference. In the example of FIG. 11, the output is performed in a state where the phase of ROT_A and the phase of ROT_B are shifted by 90 ° (π / 2). By using two signals having such a phase difference, the rotational state of the rotor 122 can be determined. In the liquid transport apparatus 1, the rotor 122 may move from when the liquid feeding operation by the pump unit 5 is stopped to when it is restarted. Is the rotation direction of the rotor 122 advanced during the pump unit 5 stop period? The amount of rotation control at the time of resuming the liquid feeding operation changes depending on whether it has returned. In such a case, by comparing the HL level of ROT_A and ROT_B at the timing when the liquid feeding operation by the pump unit 5 is stopped and the HL level of ROT_A and ROT_B at the timing when the liquid feeding operation by the pump unit 5 is restarted, respectively. It becomes possible to detect the rotation direction and the rotation amount of the rotor 122 from the stop of the pump unit 5 to the resumption of operation.

  For example, at a certain timing T1 in FIG. 11, the output signal ROT_A indicates the H level and the output signal ROT_B indicates the L level. When the predetermined minute time has elapsed from this state, if the output signal ROT_A indicates the L level and the output signal ROT_B also indicates the L level (T2 in FIG. 11), the rotor 122 has shifted in the reverse direction. I understand that. Conversely, if the output signal ROT_A indicates the H level and the output signal ROT_B also indicates the H level (in the case of T3 in FIG. 11), it can be understood that the rotor 122 has shifted in the forward rotation direction. Thus, by examining the level of the output signal ROT_B with respect to the change in the level of the output signal ROT_A, it is possible to determine whether the rotation has advanced or returned.

<About liquid transport operation>
As described above, the liquid transport operation by the liquid transport device 1 is performed by sequentially pressing the plurality of fingers 22 while rotating the cam 11 to swing the tube 21 and moving the liquid filled in the tube 21. Is called. Therefore, in order to realize a highly accurate liquid transport operation, it is required to accurately control the rotation amount of the cam 11. In particular, when the liquid transport device 1 is used as an insulin injection device or the like, high-precision control is required for the insulin injection amount and the injection timing. For example, in the insulin infusion device, intermittent driving is performed in which after 3 seconds of insulin infusion operation, the infusion operation is stopped for 57 seconds. Here, the maximum injection amount per one time is about 30 U (unit: 1 unit = about 10 μl).

  When such intermittent driving is performed, noise may be included in the output signals ROT_A and ROT_B representing the rotation state of the rotor 122 detected by the detection unit 40. For example, due to backlash of the rotor 122 or the deceleration transmission mechanism 123, noise is generated when the stopped rotor 122 is restarted, or electrical noise is included in the drive signal of the piezoelectric actuator 121 (the SN ratio is small). It is conceivable that Moreover, the influence of the noise which generate | occur | produces on the structure of the drive mechanism 12 of this embodiment can be considered.

  FIG. 12 is a side view for explaining the operation when the detection unit 40 detects the rotation angle of the rotor 122. FIG. 12 shows an example in which the rotation angle of the rotor 122 is detected by the first rotor rotation angle detection unit 43 in the detection unit 40, but other detection units such as the second rotor rotation angle detection unit 44 are shown. The configuration is basically the same. As shown in FIG. 12, in the drive mechanism 12 of this embodiment, the vibrating body provided in the piezoelectric actuator 121 is urged by a spring from the lateral direction with respect to the rotor 122. And the rotor 122 is rotationally driven by vibrating the vibrating body and bringing the end of the vibrating body into contact with the outer peripheral portion of the rotor 122 intermittently. At this time, the light emitted from the light emitting unit 43A of the first rotor rotation angle detecting unit 43 provided below the rotor 122 is reflected by the first rotor side reflecting unit 124 of the rotor 122 and received by the light receiving unit 43B. Then, the first rotor rotation angle detector 43 outputs an output signal ROT_A according to the amount of received light.

  In such a configuration, when the rotor 122 is rotated, a force that lifts the rotor 122 upward acts around a contact portion between the rotor 122 and the vibrating body. In the present specification, the influence of such force is referred to as “aori”. On the other hand, when the rotor 122 is stopped, the force against the rotor 122 is less likely to act, so that “anchor” is unlikely to occur. When the “tilting” occurs, the vertical position of the rotor 122 is displaced by several μ to several tens of μm as compared with the case where the “tilting” does not occur, so that the first rotor rotation angle detection unit 43 The optical path length varies. As a result, the magnitude of the voltage detected by the light receiving unit 43B varies, and a potential opposite to the potential that should be output may be output. For example, the first rotor rotation angle detector 43 may output the H level output signal ROT_A, but may output the L level output signal ROT_A. That is, there is a possibility that the influence of the “tilt” becomes noise and information on the accurate rotational position of the rotor 122 cannot be obtained, and the control unit 50 cannot perform accurate liquid transportation. Further, so-called chattering in which the output signal ROT_A vibrates vigorously between the H level and the L level due to the influence of noise may occur, making it difficult to detect the actual rotation angle of the rotor 122.

<Improvement of liquid transport accuracy>
In order to realize a highly accurate liquid transport operation by the liquid transport apparatus 1, it is important to reduce the influence of noise and the like generated when the rotor 122 is rotated and stopped. In the present embodiment, the storage unit 52 stores whether the output signal (for example, ROT_A described above) at the time when the rotor 122 is stopped is at the H level or the L level. When rotating the rotor 122 again, the state of the output signal stored at the stop time is referred to, and the state of the output signal at the stop time is set in a circuit for outputting the output signal. A shift is unlikely to occur when the rotor 122 is stopped and when the operation is resumed. At that time, the circuit that outputs the output signal has a hysteresis characteristic so that the rotation angle of the rotor 122 when the drive mechanism 12 is intermittently driven can be accurately detected.

  FIG. 13 is a diagram illustrating a circuit (hereinafter referred to as an encoder circuit 400) that outputs an output signal ROT_A. FIG. 13 shows an example in which the output signal ROT_A is output by the first rotor rotation angle detection unit 43 in the detection unit 40, but the same applies to other detection units such as the second rotor rotation angle detection unit 44. Circuit. Hereinafter, the operation of outputting the output signal ROT_A with high accuracy by the encoder circuit 400 will be described with reference to FIG.

  The encoder circuit 400 includes a first rotor rotation angle detector 43, a voltage follower 401, voltage follower resistors 402A and 402B, a comparator circuit 410, a reset circuit 420, ALL POW SW, and ROT_A SW. .

  First, ROT_A SW for turning on the light emitting unit 43A of the first rotor rotation angle detecting unit 43 is turned on, and then ALL POW SW for turning on the light receiving unit 43B is turned on. Note that a reference voltage Vb described later is supplied to the comparator 411 by turning on the ALL POW SW. The light emitted from the light emitting unit 43A and reflected by the first rotor side reflecting unit 124 of the rotor 122 is received by the light receiving unit 43B. The light receiving unit 43B outputs a voltage having a magnitude corresponding to the amount of received reflected light, and the voltage is input to the positive terminal side of the voltage follower 401. The negative terminal side of the voltage follower 401 is a feedback loop, and the voltage input to the voltage follower 401 is impedance-converted and output. The voltage output from the voltage follower 401 is input to the negative terminal side of the comparator 411 of the comparator circuit 410 via the resistor 421 of the reset circuit 420.

(Comparator circuit 410)
The comparator circuit 410 is a circuit that outputs an H level or L level voltage signal according to the magnitude of the input voltage. The comparator circuit 410 of the present embodiment includes a comparator 411, reference voltage resistors 412A and 412B, voltage dividing resistors 413A and 413B, and hysteresis resistors 414A and 414B.

  The reference voltage Vb is input as a reference value to the plus side input terminal of the comparator 411, and the input voltage Vin is input to the minus side input terminal. When the input voltage Vin is equal to or higher than the reference voltage Vb (Vin ≧ Vb), an L level voltage signal is output, and when the input voltage Vin is smaller than the reference voltage Vb (Vin <Vb), the H level signal is output. Outputs a voltage signal. This output voltage signal becomes ROT_A. In this embodiment, the voltage whose magnitude is adjusted is input from the power source (3.3 V) through the reference voltage resistors 412A and 412B to the positive input terminal of the comparator 411 as the reference voltage Vb. On the other hand, the voltage detected by the first rotor rotation angle detector 43 is input to the negative input terminal of the comparator 411 as the input voltage Vin via the voltage follower 401 and the resistor 421. For example, when the reference voltage Vb = 2.5V, if the input voltage Vin is 2.5V or more, the output signal ROT_A of L level (for example, 0V) is output, and if the input voltage Vin is smaller than 2.5V, the output signal ROT_A is H. An output signal ROT_A having a level (eg, 3.3 V) is output.

  Here, when noise is included in the output voltage of the first rotor rotation angle detector 43, the magnitude of the input voltage Vin may vibrate with a predetermined width. For example, when the input voltage Vin oscillates up and down in the vicinity of the reference voltage Vb = 2.5 V in the above example, the output signal ROT_A fluctuates (chatters) between H level and L level, and the rotor 122 is accurately The rotation status cannot be grasped. With respect to such a problem, the comparator circuit 410 according to the present embodiment is provided with hysteresis resistors 414A and 414B, thereby giving the circuit hysteresis characteristics and suppressing chattering of the output signal ROT_A.

  The hysteresis resistors 414A and 414B are provided between the output side terminal and the input side terminal (plus side terminal) of the comparator 411. When the voltage at the output side terminal of the comparator 411 (output signal ROT_A) is at the H level, the reference voltage Vb depends on the relationship between the hysteresis resistors 414A and 414B, the reference voltage resistors 412A and 412B, and the reference voltage resistors 413A and 413B. Becomes a value Vbh larger than the original value and is input to the plus side input terminal of the comparator 411 (Vbh> Vb). Conversely, when the output signal ROT_A is at the L level, the reference voltage Vb is smaller than the original value due to the relationship between the reference voltage resistors 412A and 412B, the hysteresis resistors 414A and 414B, and the reference voltage resistors 413A and 413B. Vbl is input to the positive input terminal of the comparator 411 (V> Vblb). That is, a reference value setting unit is configured by the reference voltage resistors 412A and 412B, the reference voltage resistors 413A and 413B, and the hysteresis resistors 414A and 414B, and the reference voltage Vb of the comparator 411 is operated by the function of the reference value setting unit. Varies between Vbl and Vbh.

  FIG. 14 is a diagram illustrating the hysteresis characteristic. In FIG. 14, when the input voltage Vin is smaller than the reference voltage Vb, the H level is initially output as the output signal ROT_A, so the reference voltage Vb rises to Vbh. In this case, the output signal ROT_A becomes the L level when the input voltage Vin gradually increases and reaches the reference voltage Vbh after the increase. On the other hand, when the input voltage Vin is larger than the reference voltage Vb, the L level is initially output as the output signal ROT_A, so the reference voltage Vb drops to Vbl. In this case, the output signal ROT_A becomes H level when the input voltage Vin gradually decreases and becomes lower than the reference voltage Vbl after the decrease. That is, even if the input voltage Vin fluctuates near the reference voltage Vb due to the influence of noise or the like, the H level / L level of the output signal ROT_A does not fluctuate immediately, but the output signal ROT_A fluctuates in the range of Vbl to Vbh. It becomes difficult. In such a circuit, once the level of the output signal ROT_A is switched, the reference voltage changes again, so that the output signal ROT_A is less likely to fluctuate even if the input voltage Vin slightly increases or decreases. For example, when the input voltage Vin gradually increases from a value smaller than Vb and becomes larger than the reference voltage Vbh, the reference voltage changes to Vbl. Therefore, even if the input voltage Vin oscillates near Vbh, the reference voltage is Vbl. The output signal ROT_A is kept at the L level as long as it does not become smaller.

  That is, in the encoder circuit 400 of the present embodiment, chattering of the output signal ROT_A can be suppressed by outputting the output signal ROT_A based on the hysteresis characteristics, so that fluctuations in the output value of the encoder are reduced, noise, etc. It is easy to obtain an accurate output value with less influence.

(Resetting circuit 420)
As described above, when the driving and stopping of the drive mechanism 12 are repeated, the first rotor rotation angle may be caused by the rotor 122 slightly moving between the stop of the rotor 122 and the restart of rotation. The detection value detected by the detection unit 43 may vary. In the conventional encoder circuit, since the rotation of the rotor 122 is controlled based on the detection value at the time of restarting the drive, if the state at the time of stopping the drive is different from the state at the time of restarting the drive, the liquid transport amount can be accurately controlled. It was difficult. In particular, when the liquid transport apparatus is used as an insulin injector, it is required to inject an optimal amount of insulin to the patient, and thus it is necessary to perform more accurate liquid transport control. Therefore, in the encoder circuit 400 of the present embodiment, the reset voltage circuit 420 resets the reference voltage value when the driving is resumed, thereby suppressing the fluctuation of the detected value, and the liquid transport apparatus 1 is intermittently driven. Even in this case, an accurate output signal ROT_A can be output.

  As illustrated in FIG. 13, the reset circuit 420 includes resistors 421 and 422 and a reset unit 423. The resetting unit 423 is a voltage supply unit that outputs a predetermined voltage value according to the level of the output signal when the driving mechanism 12 is stopped. The resetting unit 423 is also a storage unit that stores the output signal ROT_A output from the encoder circuit 400. When the liquid transport apparatus 1 stops the liquid transport operation, the control unit 50 causes the resetting unit 423 to store whether the output signal ROT_A was at the H level or the L level when the rotor 122 that was being rotationally driven stopped. . When the liquid transport apparatus 1 restarts the liquid transport operation, the reset voltage having a magnitude corresponding to the level opposite to the level (H level or L level) of the stored output signal ROT_A is output, and the resistor 422 is output. To the negative input terminal of the comparator 411. As a result, the comparator 411 outputs the output signal ROT_A in the same state as when the rotor 122 is stopped.

  For example, it is assumed that the H level output signal ROT_A is output when the rotation of the rotor 122 is stopped. In this case, the resetting unit 423 inputs a resetting voltage corresponding to the L level as the input voltage Vin to the negative side input terminal of the comparator 411. Then, since the input voltage Vin becomes smaller than the reference voltage Vb, the comparator 411 outputs the H level output signal ROT_A. When the H level output signal ROT_A is output, the reference voltage Vb of the comparator 411 increases to Vbh, and in the subsequent operation of the rotor 122, the output signal ROT_A is output with reference to Vbh. When the output signal ROT_A at the L level is output at the time when the rotation of the rotor 122 is stopped, the resetting unit 423 inputs a resetting voltage corresponding to the H level to the comparator 411. As a result, the comparator 411 outputs the L level output signal ROT_A. As described above, by providing the resetting circuit 420, it is possible to suppress a deviation between the output signal when the drive of the drive mechanism 12 is stopped and the output signal when the drive is restarted.

  Note that the configuration of the resetting circuit 420 can be modified. FIG. 15 is a diagram for explaining a modification of the encoder circuit 400. The modified encoder circuit 400 is basically the same as the encoder circuit 400 shown in FIG. 13, but the connection position and operation of the reset circuit 420 are different. In the modification, the reset circuit 420 is provided on the output side of the comparator 411. Then, the magnitude (H level or L level) of the output signal ROT_A is adjusted by directly applying to the output side of the comparator 411 a reset voltage having the same level as the voltage when driving is stopped. In the example of FIG. 15, the resetting unit 423 stores the level of the output signal ROT_A when the rotor 122 that has been rotationally driven stops, and outputs the voltage of the same level when the driving of the rotor 122 is resumed. For example, when the H-level output signal ROT_A is output when the rotation of the rotor 122 is stopped, the resetting unit 423 of the modification applies a voltage corresponding to the H level to the output-side terminal of the comparator 411. Since the output signal ROT_A becomes H level, the reference voltage of the comparator 411 increases to Vbh, and in the subsequent operation of the rotor 122, the output signal ROT_A is output based on Vbh. Accordingly, it is possible to suppress a deviation between the output signal when the drive of the drive mechanism 12 is stopped and the output signal when the drive is restarted. Note that the position where the reset circuit 420 is provided in the modification is not limited to the example of FIG. 15, and any position between the output side terminal and the plus side input terminal of the comparator 411 may be provided. Good.

<Reduction of energy consumption>
In this embodiment, in order to realize the liquid transport operation with high accuracy, the rotation angle of the rotor 122 and the cam 11 is detected by an optical sensor such as the first rotor rotation angle detection unit 43 provided in the detection unit 40. Yes. In such an optical sensor, it is necessary to continuously supply power to the light emitting unit and the light receiving unit during detection. On the other hand, in the liquid transport apparatus 1 of the present embodiment, as described above, intermittent driving is assumed in which the driving is performed for 3 minutes and then stopped for 57 minutes. . Since the comparator circuit 410 can suppress the change in the state of the output signal between when the drive is stopped and when the drive is restarted, there is no need to monitor the rotational angle deviation of the rotor 122 or the like during the stop. Because.

  Therefore, the control unit 50 supplies power to the detection unit 40 only for a predetermined period for driving the drive mechanism 12, and controls so that power is not supplied to the detection unit 40 while the drive mechanism 12 is stopped. The energy consumed by the detection unit 40 during the stop is reduced. FIG. 16 is a diagram illustrating a flow when the drive mechanism 12 is changed from the stop state to the drive state. FIG. 17 is a diagram illustrating a flow when the drive mechanism 12 is changed from the drive state to the stop state. FIG. 18 is a diagram for explaining power supply control when the drive mechanism 12 is changed from the stopped state to the driven state.

  When the drive mechanism 12 is started (restarted) from a stopped state, a drive start signal that is a logic signal that defines the start of drive is generated. The drive start signal may be generated periodically by managing it with a timer or the like, or may be generated when the user of the liquid transport apparatus 1 gives an instruction (operation) to start injection. good. In FIG. 16, when the control unit 50 detects the drive start signal, various controls for driving the drive mechanism 12 are started (S101). When detecting the drive start signal, the control unit 50 first turns on the switch of the power supplied to the detection unit 40 (S102). Here, the switch of power supplied to the detection unit 40 is a switch that supplies power to the light emitting unit of the optical sensor (rotary encoder). For example, the ROT_A SW in FIG. 13 or the light emitting unit of another encoder. It is a power switch. By turning on the switch of the power source, each encoder such as the first rotor rotation angle detector 43 starts to emit light. Subsequently, the control unit 50 sets a standby time (S103). As shown in FIG. 18, the standby time is a period from when the power switch of the light emitting unit of the encoder is turned on to when driving is started by applying a drive signal to the drive mechanism 12 (the rotor 122 or the like). It's about time. In this embodiment, in the encoder circuit as shown in FIG. 13, the fluctuation of the detected value of the encoder is reduced by adjusting the magnitude of the reference voltage input to the comparator by the hysteresis characteristic. Therefore, the rotation angle of the rotor 122 and the like can be detected more accurately by waiting for a predetermined time until the reference voltage becomes stable. After the standby time is set, the control unit 50 sets a reference potential (S104). The setting of the reference potential when starting the drive of the drive mechanism 12 is performed using the reset circuit as described above. That is, the control unit 50 stores in the resetting unit whether the output signal (for example, ROT_A) of the encoder circuit at the time when the drive mechanism 12 is stopped is at the H level or the L level. This is done by applying a voltage corresponding to the output signal to the comparator.

  Thereby, even when the drive mechanism 12 is intermittently driven, accurate drive control can be performed. When the setting of the reference potential is completed and the standby time has elapsed, the control unit 50 turns on the power switch of the encoder circuit (S105). The power switch for the encoder circuit is a main power switch for the entire circuit that activates the piezoelectric actuator 121 and supplies power to the light receiving portion of the optical sensor (rotary encoder). POW SW. When the power supply is turned on, driving of the drive mechanism 12 is started. The detection values detected from the rotor 122 and the cam 11 that are driven to rotate are corrected as appropriate according to the hysteresis characteristics as described above, so that accurate control is performed (S106).

  In FIG. 17, when the drive mechanism 12 is stopped, a drive stop signal that is a logic signal that defines the drive stop is generated and detected by the control unit 50 to start various controls for stopping the drive mechanism 12. (S201). When the drive stop signal is detected, the control unit 50 turns off the power switch that drives the drive mechanism 12 (S202). As a result, the piezoelectric actuator 121 stops and the detection unit 40 also stops detecting the rotation angle of the rotor 122 and the like. Subsequently, the control unit 50 causes the resetting unit to store whether the output signal (for example, ROT_A) of the encoder circuit at the time when the drive mechanism 12 is stopped is at the H level or the L level (S203). When the driving is resumed, the reference potential is set using this data (S104). After storing the output signal, the control unit 50 sets a standby time (S204). The standby time in the stop operation is a predetermined time from when the power source for driving the drive mechanism 12 is turned off until the drive mechanism 12 completely stops operating. Then, after the standby time has elapsed and the drive mechanism 12 has completely stopped, the control unit 50 turns off the switch of the power supplied to the detection unit 40 (S205). Thereby, the stop operation of the drive mechanism 12 is completed.

  In the present embodiment, the power consumption in the detection unit 40 can be reduced by performing such control of the power supply when the drive mechanism 12 is started and stopped. For example, as shown in FIG. 18, when the drive is started, the power of the encoder is turned on at a timing slightly earlier than the timing at which the piezoelectric actuator 121 is actually activated, specifically, the waiting time. As soon as possible, the encoder is turned off before that. In addition, when the drive is stopped, the power of the encoder is turned off at a timing slightly later than the timing at which the piezoelectric actuator 121 actually stops, specifically, a timing that is later by the waiting time. That is, the power source of the detection unit 40 is turned on before and after the timing when the drive mechanism 12 is driven, and is turned off at other timings. Then, in synchronization with the timing at which the power supply of the drive mechanism 12 is switched between the ON state and the OFF state, the encoder power supply is switched between the ON state and the OFF state. Therefore, in the intermittent drive in which the drive mechanism 12 is driven for 3 seconds out of 1 minute as described above, the time during which the power source of the detection unit 40 is turned on is short and the time during which the power is turned off is long. Thereby, the power consumption of a detection part (encoder) can be reduced. In particular, it is possible to reduce power consumption in the light emitting unit of an encoder that consumes a large amount of power.

=== Others ===
The above-described embodiments are for facilitating the understanding of the present invention, and are not intended to limit the present invention. The present invention can be changed and improved without departing from the gist thereof, and it is needless to say that the present invention includes equivalents thereof.

<About the detector>
In the above-described embodiment, the rotor 122 of the drive mechanism 12 is provided with a rotary encoder (the first rotor rotation angle detection unit 43, the second rotor rotation angle detection unit 44, the rotor rotation detection unit 45). However, a rotary encoder may be provided at another position. For example, the transmission wheel 123A of the deceleration transmission mechanism 123 may be provided with a rotary encoder similar to the first rotor rotation angle detection unit 43 to detect the rotation angle of the transmission wheel 123A. Similarly, the cam 11 may be provided with a rotary encoder similar to the first rotor rotation angle detection unit 43, and the rotation angle of the cam 11 may be directly detected. By detecting the rotation angle at a position close to the cam 11, the influence of backlash or the like is less likely to be included, and the actual operation when the projection 11 </ b> A of the cam 11 presses the finger is easily detected. However, since the rotation of the cam 11 is decelerated at a predetermined reduction ratio with respect to the rotation of the rotor 122, data with higher resolution can be detected by detecting the rotation angle of the rotor 122.

<About the pump unit>
In the above-described embodiment, as an example of using a so-called tube pump that transports liquid in a tube by squeezing the tube with a plurality of fingers as the pump unit of the liquid transport device, the configuration of the pump unit is described. This is not the case. For example, a screw pump that rotates a screw to transport liquid in the axial direction, or a plunger pump that converts rotation of a cam into plunger movement and transports liquid by reciprocating movement of the plunger. Other possible pumps may be used.

1 Liquid transport device,
5 Pump part,
10 body, 11 cam, 12 drive mechanism, 19 battery,
111 Cam side reflection part,
121 piezoelectric actuator, 122 rotor, 123 deceleration transmission mechanism,
123A Transmission wheel, 124 1st rotor side reflection part, 125 2nd rotor side reflection part,
20 cartridges, 21 tubes, 22 fingers,
25 tube guide wall, 26 reservoir,
30 patches,
40 detector,
41 cam rotation detection unit, 41A light emitting unit, 41B light receiving unit,
43 first rotor rotation angle detection unit, 43A light emitting unit, 43B light receiving unit,
43BR resistance,
44 second rotor rotation angle detection unit, 44A light emitting unit, 44B light receiving unit,
45 rotor rotation detector, 45A light emitter, 45B light receiver,
50 control unit,
51 counter, 52 storage unit, 53 calculation unit, 54 driver,
400 encoder circuit,
401 voltage follower, 402A, 402B voltage follower resistance,
410 comparator circuit,
411 comparator,
412A, 412B reference voltage resistance, 413A, 413B voltage dividing resistance,
414A, 414B hysteresis resistance,
420 resetting circuit,
421 resistor, 422 resistor, 423 resetting unit

Claims (6)

A drive mechanism having a rotor that rotates when transporting liquid;
An encoder for detecting a rotation angle of the rotor;
A comparator that compares a detection value detected by the encoder with a predetermined reference value and outputs a signal having an H level or an L level;
A reference value setting unit that detects the output signal and changes the reference value;
A liquid transport apparatus comprising: The liquid transport device according to claim 1,
The drive mechanism has a piezoelectric actuator that contacts a vibrating body that vibrates when a drive signal is applied to the rotor and rotates the rotor;
The piezoelectric actuator is biased so that an end of the vibrating body and an outer peripheral portion of the rotor are in contact with each other in a state where a vibration trajectory of the vibrating body and a rotation surface of the rotor are parallel to each other. Liquid transport device. The liquid transport device according to claim 1 or 2,
Comprising a cam for transporting liquid by being rotated by rotation of the rotor;
The drive mechanism has a speed reducing portion that reduces the rotation of the rotor and transmits it to the cam.
The liquid transport apparatus according to claim 1, wherein the detection unit detects a rotation angle of the speed reduction unit. The liquid transport device according to claim 1 or 2,
Comprising a cam that is rotationally driven by the rotation of the rotor and transports the liquid;
The drive mechanism has a speed reducing portion that reduces the rotation of the rotor and transmits it to the cam.
The liquid transport apparatus according to claim 1, wherein the detection unit detects a rotation angle of the cam. The liquid transport device according to any one of claims 1 to 4,
When performing intermittent driving in which driving and stopping of the driving mechanism are repeated, the level of the signal output when the driving mechanism is stopped is stored,
A liquid having a resetting unit that applies a resetting voltage having a magnitude corresponding to the stored signal level to a predetermined terminal of the comparator circuit when the driving mechanism is driven again. Transport equipment. Detecting the rotation angle of the rotor that rotates when transporting the liquid;
Comparing the detected detection value with a predetermined reference value and outputting a signal having an H level or an L level;
Detecting the output signal and changing the reference value;
A method for transporting liquids.

Images