Pump device

Abstract

The utility model provides a pump device which can be formed at low cost and can simply and conveniently deduce the flow and the operation state of the pump device without being influenced by the characteristics of conveyed fluid and pipeline conditions. The pump device is provided with a pump head having a suction port and a discharge port for conveying fluid, and a diaphragm attached to the pump head and forming a pump chamber for communicating the suction port and the discharge port; and a pump body including a reciprocating member connected to the diaphragm and provided so as to be movable in the reciprocating direction of the diaphragm, a drive mechanism capable of driving the reciprocating member in the reciprocating direction of the diaphragm, and a control unit for controlling the drive mechanism, and further provided with: a sensor unit for sensing the reciprocating member in the reciprocating direction of the diaphragm; a strain sensor that is provided in a portion of the pump device that is not in contact with the conveyed fluid, and that detects strain generated at the non-contact portion when the pump device is operated; and an estimation unit that estimates the actual flow rate of the conveyed fluid in the pump device or the pressure of the conveyed fluid.

Description

Technical Field

[0001] The utility model relates to a pump device. Background Art

[0002] Conventionally, a pump device is known which has a structure in which a pump head is mounted on a pump main body housing a drive mechanism of the pump. For example, in a pump device in which a reciprocating motion member such as a diaphragm reciprocates, the pressure in the pump chamber is obtained by a pressure sensor mounted on the pump head or the like, and the flow rate of the fluid to be transported is determined to judge the operating state, thereby suppressing, for example, a failure caused by a large accumulation of bubbles in the pump chamber (see Patent Document 1).

[0003] Prior Art Documents

[0004] Patent Documents

[0005] Patent Document 1: Japanese Patent Publication No. 6022943 Summary of the Invention

[0006] Technical Problems to be Solved by the Invention

[0007] However, in the pump device of the prior art disclosed in the above Patent Document 1, a structure in which a pressure sensor is provided at a position in contact with the fluid to be transported is adopted. Therefore, in the case of transporting a fluid having characteristics such as deterioration and failure of an expensive pressure sensor, this pump device is not applicable, and in this case, there are problems such as the inability to judge the flow rate of the fluid to be transported and the inability to judge the operating state of the pump device based on this judgment.

[0008] On the other hand, there is also a case where a flow meter is provided on a pipe or the like of a pump device to measure the flow rate of the fluid to be transported, but in this case, there are problems such as an increase in the cost of the flow meter and limitations on the conditions of various pipes.

[0009] The present utility model has been completed in view of the above circumstances, and an object thereof is to provide a pump device that can be configured at low cost and can simply infer the flow rate, pressure, and operating state of the pump device without being affected by the characteristics of the fluid to be transported and the pipe conditions.

[0010] Means for Solving the Technical Problems

[0011] The pump device related to the present utility model includes: a pump head formed with a suction port and a discharge port for conveying fluid; a diaphragm attached to the pump head and forming a pump chamber that connects the suction port and the discharge port; and a pump main body, which includes: a reciprocating motion member connected to the diaphragm and arranged to be movable along the reciprocating motion direction of the diaphragm, a driving mechanism capable of driving the reciprocating motion member along the reciprocating motion direction of the diaphragm, and a control unit for controlling the driving mechanism. The pump device includes: a sensor unit, which is arranged at a position in the pump device that is non-contact with the conveyed fluid and detects the strain generated at the non-contact position when the pump device operates; and an inference unit, which infers the actual flow rate of the conveyed fluid or the pressure of the conveyed fluid in the pump device based on the amount of strain at the non-contact position detected by the sensor unit.

[0012] In an embodiment of the present utility model, the control unit controls the operation of the driving mechanism based on the inference result of the actual flow rate obtained by the inference unit so that the actual flow rate of the conveyed fluid becomes a preset set flow rate.

[0013] In another embodiment of the present utility model, it further includes a storage unit that stores information prepared in advance for each number of strokes of the reciprocating motion member, and this information shows the actual flow rate ratio corresponding to the potential difference of the waveform data representing the amount of strain. The inference unit infers the actual flow rate according to the potential difference of the waveform data representing the amount of strain and referring to the information showing the actual flow rate ratio in the storage unit.

[0014] In yet another embodiment of the present utility model, the control unit further includes a display unit that visually displays the information of the inferred actual flow rate together with the set flow rate.

[0015] In yet another embodiment of the present utility model, when the output value of the waveform data representing the amount of strain is greater than a specified threshold after a specified time has elapsed since the start of the suction period of the pump device, or when the output value of the waveform data representing the amount of strain is less than a specified threshold after a specified time has elapsed since the start of the discharge period of the pump device, the inference unit infers that the operating state of the pump device is abnormal operation.

[0016] In yet another embodiment of the present utility model, the sensor unit is arranged at the non-contact position on the outer periphery near the position of the reciprocating motion member that is connected to the diaphragm.

[0017] In yet another embodiment of the present utility model, a plurality of the sensor units are arranged at the non-contact position.

[0018] In another embodiment of the present utility model, the sensor unit is disposed at the non-contact portion of at least one of the following positions: a reinforcing member mounted on the front side of the pump head, a holder member disposed on the back side of the diaphragm, a bracket member mounted on the front side of the drive mechanism, the outer periphery of the reciprocating member located on the rear side more forward than the front of the bracket member, and the upper portion of the drive mechanism.

[0019] Effects of the Invention

[0020] According to the present utility model, a pump device can be configured at low cost, and the pump device can simply infer the flow rate, pressure, and operating state of the pump device without being affected by the characteristics of the fluid to be transported and the pipeline conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 is a side sectional view schematically showing a pump device according to the first embodiment of the present utility model.

[0022] Figure 2 is Figure 1 A arrow view of

[0023] Figure 3 is a block diagram schematically showing the circuit structure of the pump device.

[0024] Figure 4 is a graph showing the inferred flow rate and the measured flow rate of the pump device.

[0025] Figure 5 is a graph showing the inferred flow rate and the measured flow rate of the pump device.

[0026] Figure 6 is a graph showing the inhalation period and the discharge period of the pump device and the strain waveform data.

[0027] Figure 7 is a diagram showing an example of data stored in the storage unit of the pump device.

[0028] Figure 8 is a diagram showing an example of display on the display unit of the pump device.

[0029] Figure 9 is a sectional view schematically showing the installation position of the sensor unit in the pump device according to the second embodiment of the present utility model.

[0030] Figure 10 is a sectional view schematically showing the installation position of the sensor unit in the pump device according to the third embodiment of the present utility model.

[0031] Figure 11It is a cross-sectional view schematically showing the installation position of the sensor unit in the pump device according to the 4th embodiment of the present utility model.

[0032] Figure 12 It is a cross-sectional view schematically showing the installation position of the sensor unit in the pump device according to the 5th embodiment of the present utility model.

[0033] Figure 13 It is a cross-sectional view schematically showing the installation position of the sensor unit in the pump device according to the 6th embodiment of the present utility model.

[0034] Explanation of reference numerals

[0035] 10 Driving mechanism

[0036] 11 Shaft member

[0037] 11a First member

[0038] 11b Second member

[0039] 16 Strain gauge

[0040] 20 Pump body

[0041] 21, 25 Storage space

[0042] 26 Front housing

[0043] 27 Rear housing

[0044] 29 Control board

[0045] 29a Sensor board

[0046] 30 Pump head

[0047] 31 Pump chamber

[0048] 40 Adapter member

[0049] 50 Diaphragm

[0050] 54 Fixing member

[0051] 60 Washer member

[0052] 73 Control unit

[0053] 74 Inference unit

[0054] 75 Storage unit

[0055] 100 Pump device Detailed implementation manners

[0056] In the following, with reference to the accompanying drawings, the pump device according to the embodiment of the present utility model will be described in detail. However, the following embodiments do not limit the utility model related to each claim, and in addition, the combination of features described in the embodiments is not necessarily required for the solution of the utility model.

[0057] In addition, in the following embodiments, for the same or equivalent components, the same reference numerals are marked and repeated descriptions are omitted. In addition, in the embodiments, the arrangement, ratio, dimensions, etc. of each component are sometimes exaggerated or reduced and shown in a state inconsistent with the actual situation, and sometimes the description of a part of the components is omitted.

[0058] [First Embodiment]

[0059] [Structure of the Pump Device]

[0060] Figure 1 is a side sectional view schematically showing the pump device according to the first embodiment of the present utility model. Figure 2 is Figure 1 A arrow view of Figure 3 is a block diagram schematically showing the circuit structure of the pump device.

[0061] As Figure 1 shown, the pump device 100 of the first embodiment includes: a pump main body 20 having a drive mechanism 10 as a drive source (drive unit) and a control substrate 29; and a pump head 30 mounted on the front side of the pump main body 20. It should be noted that the basic configuration of the pump device 100 of the present embodiment, including the internal structure, can be constituted by a so-called ordinary pump device. Therefore, the known structures are not described in detail below and only the outline is explained.

[0062] The pump device 100 further includes: an adapter member 40 provided between the pump head 30 and the pump main body 20 for mounting the pump head 30 on the pump main body 20; and a diaphragm 50 clamped by the adapter member 40 and mounted on the pump head 30, and connected to the shaft member 11 which is a reciprocating member of the drive mechanism 10 through the adapter member 40.

[0063] In addition, the pump device 100 also has a strain gauge 16 as a sensor unit provided at a portion of the pump device 100 that is not in contact with the fluid to be transported. In the following, the direction of the pump main body 20 toward the pump head 30 is denoted as the front, and the direction opposite to the front is denoted as the rear. As Figure 1 shown by the arrow in

[0064] [Structure of the Drive Mechanism]

[0065] The drive mechanism 10 includes, for example: a motor 12, an eccentric cam mechanism 13, and a shaft member 11. The motor 12 drives the rotary shaft 13a of the eccentric cam mechanism 13 to rotate through a gear mechanism 12a. The eccentric cam mechanism 13 converts the rotary motion of the rotary shaft 13a into a reciprocating motion of the shaft member 11 through an eccentric cam portion 13b. The shaft member 11 is driven in the reciprocating motion direction RD in the front and rear directions by the reciprocating motion converted by the eccentric cam mechanism 13.

[0066] The shaft member 11 is constituted of, for example, a rod-shaped metal member or a resin member, and includes: a first member 11a provided on the front side in a manner connected to the diaphragm 50, and a second member 11b connected and provided on the rear side of the first member 11a and connected to the eccentric cam portion 13b of the eccentric cam mechanism 13.

[0067] While the shaft member 11 is pushed forward by the eccentric cam portion 13b, the front flange portion 11c of the second member 11b is pushed forward by the repulsive force of the spring member 14, so as to move toward the front side of the pump body 20, causing the diaphragm 50 to be displaced in the forward direction. In addition, the shaft member 11 is pulled back toward the rear side of the pump body 20 by the eccentric cam portion 13b with a force stronger than the repulsive force of the spring member 14 through the front flange portion 11c of the second member 11b, so as to move toward the rear side of the pump body 20, causing the diaphragm 50 to be displaced in the backward direction.

[0068] In this way, the shaft member 11 is pushed and pulled by the eccentric cam portion 13b in the drive mechanism 10 and repeats the forward and backward movements as described above, so as to perform a reciprocating motion in the reciprocating motion direction RD. It should be noted that on the front side (front surface) of the drive mechanism 10, a bracket portion 15 serving as a bracket member facing the front opening 20a of the pump body 20 is provided to mount an adapter member 40 described below.

[0069] In addition, the drive mechanism 10 is not limited to the structure having the motor 12 and the eccentric cam mechanism 13 described above as long as its structure can drive the shaft member 11 at least in the forward or backward direction of the diaphragm 50 as described above. For example, it may also be a structure employing an actuator or the like that directly drives the shaft member 11 using, for example, electromagnetic force or the like.

[0070] [Structure of the pump body]

[0071] The housing portion constituting the pump main body 20 is formed of, for example, a resin member. That is, the pump main body 20 has a front housing 26, a rear housing 27 connected thereto, and a pump base 20b. The front housing 26 has a front opening 20a provided on the front side, and a storage space 21 provided above the pump base 20b and connected to the front opening 20a. The rear housing 27 has a storage space 25 capable of storing the control board 29.

[0072] The storage space 21 in the front housing 26 of the pump main body 20 is formed, for example, in a cylindrical shape, and is configured such that a part thereof (for example, the lower side) is connected to the inside of the pump base 20b. The storage space 25 in the rear housing 27 of the pump main body 20 is separated from the storage space 21 in the reciprocating motion direction RD, but is formed in the same shape as or a rounded rectangular shape as the storage space 21, and is configured such that a part thereof (for example, the lower side) is connected to the inside of the pump base 20b.

[0073] In the storage space 21 of the front housing 26, the drive mechanism 10 is mainly stored, and also stored are, for example, a wire pipe 19a that stores a cable 19 as a wiring and is wound around the drive mechanism 10, and the above-described bracket portion 15. The front housing 26 has a rear wall 22 provided on the rear side. The rear housing 27 is attached to the back surface (rear side surface) 22a of the rear wall 22 of the front housing 26 by screwing with mounting screws 27a.

[0074] The control board 29 is directly attached to the rear housing 27 by screwing with mounting screws 27b. The cable 19 of the wire pipe 19a is connected to the control board 29. The control board 29 controls the drive mechanism 10 and controls the operation of the entire pump device 100.

[0075] It should be noted that an operation unit 28 is provided on the rear side of the pump main body 20, and the operation unit 28 is used for operation inputs such as setting operations of the pump device 100 by an operator, for example. The operation unit 28 includes a display unit 28a that visually displays various information related to the pump device 100.

[0076] [Setting of the sensor unit]

[0077] The strain gauge 16 as the sensor unit is provided at a portion not in contact with the fluid to be transported, for example, at the outer periphery of the first member 11a of the shaft member 11 near the portion connected to the diaphragm 50. The strain gauge 16 is used to detect the strain generated at the outer periphery of the first member 11a when the pump device 100 is in operation.

[0078] As Figure 2As shown, the strain gauge 16 is attached to the outer peripheral portion of the first component 11a by an adhesive or the like. However, the installation method of the strain gauge 16 is not limited to this. The strain gauge 16 may also be individually installed on the outer peripheral portion of the first component 11a as shown in the figure. In the present embodiment, although not shown in the figure, a plurality of (for example, two) strain gauges are provided on the outer peripheral portion of the first component 11a.

[0079] A lead wire 16a is connected to the strain gauge 16, and the lead wire 16a extends in a direction intersecting the reciprocating motion direction RD. The lead wire 16a extending from the strain gauge 16 is protected by, for example, a silicone resin coating. A connector 16b is connected to the end of the lead wire 16a. The connector 16b is connected to a relay connector 16c provided on a part of the bracket portion 15. The relay connector 16c is connected to a sensor substrate 29a provided, for example, on the upper part of the drive mechanism 10 through a cable 19b and a connector 16d. Since the sensor substrate 29a is connected to the cable 19 through a connector 16e, the strain gauge 16 is electrically connected to the control substrate 29 through the lead wire 16a, the connector 16b, the relay connector 16c, the cable 19b, the connector 16d, the sensor substrate 29a, the connector 16e, and the cable 19.

[0080] [Structure of the pump head]

[0081] The pump head 30 is formed of, for example, a resin component or a metal component such as stainless steel. The pump head 30 has a pump chamber 31 formed in the center. The pump chamber 31 is formed together with a diaphragm 50 attached to the pump head 30, and its volume changes as the diaphragm 50 moves. It should be noted that in the pump device 100 of the present embodiment, on the front side of the pump head 30, for example, a reinforcing plate 30a as a reinforcing component for strengthening the mechanical strength of the pump head 30 and a cover component 30b for protecting the reinforcing plate 30a are installed.

[0082] The pump head 30 is installed on the front opening 20a side of the front housing 26 through, for example, an adapter component 40 installed on the bracket portion 15 of the drive mechanism 10. The pump head 30 has a suction port 32 and a discharge port 33 for delivering fluid that communicate with the pump chamber 31. The suction port 32 communicates with the lower part of the pump chamber 31, for example. The discharge port 33 communicates with the upper part of the pump chamber 31, for example.

[0083] In the pump head 30, a first connection port 34 is formed below the suction port 32 and on the suction side of the fluid being delivered. In addition, in the pump head 30, a second connection port 35 is formed above the discharge port 33 and on the discharge side of the fluid being delivered. These first connection port 34 and second connection port 35 communicate with the pump chamber 31 through the suction port 32 and the discharge port 33, respectively.

[0084] On the first connection port 34, a cylindrical suction-side adapter 37 is connected through a connection nut 37a with an inhalation valve 36a assembled thereon. On the second connection port 35, a cylindrical discharge-side adapter 38 is connected through a connection nut 37b with a discharge valve 36b assembled thereon.

[0085] The suction-side adapter 37 is connected to a suction-side pipe (not shown), and connects the suction port 32 of the pump head 30 to the suction-side flow path 39a through the inhalation valve 36a. The discharge-side adapter 38 is connected to a discharge-side pipe (not shown), and connects the discharge port 33 of the pump head 30 to the discharge-side flow path 39b through the discharge valve 36b.

[0086] [Structure of the adapter component]

[0087] The adapter component 40 is formed of a resin component, for example. The adapter component 40 is provided between the pump head 30 and the pump body 20 (front opening 20a of the front housing 26), closes the front opening 20a, and makes the storage space 21 in a closed state. The adapter component 40 has, for example, a plurality of mounting holes (not shown) provided at a specified interval, and a plurality of through holes (not shown) provided at a specified interval different from these plurality of mounting holes.

[0088] The adapter component 40 is fixed to the bracket portion 15 by a fastening unit such as a bolt (not shown) inserted into the mounting hole. Thus, the adapter component 40 is mounted on the pump body 20 so as to block the front opening 20a of the front housing 26. It should be noted that, for example, by fastening a bolt 42a passing through the insertion hole of the reinforcement plate 30a and the adapter component 40 to the bracket portion 15 provided behind the adapter component 40, the pump head 30 is liquid-tightly sealed and mounted on the front side of the pump body 20 through the adapter component 40.

[0089] The adapter component 40 has, for example: an annular convex portion 43 that clamps the fixing portion 51 located at the outer peripheral portion of the diaphragm 50 together with the pump head 30, and a wall portion 44 continuous with the inner peripheral wall surface 43a of the annular convex portion 43. A circular central hole portion 46 is formed at the center of the wall portion 44 of the adapter component 40.

[0090] It should be noted that the gasket component 60 is mounted in a state of being clamped between the bracket portion 15 and the adapter component 40 on the back surface (the surface on the front housing 26 side) of the wall portion 44 of the adapter component 40. The gasket component 60 is formed of rubber, for example. The gasket component 60 has: a disk portion 61 that contacts the back surface of the wall portion 44, and a central convex portion 62 provided at the center of the disk portion 61 and having an uneven shape (serpentine in a direction intersecting the reciprocating motion direction RD) in the reciprocating motion direction RD.

[0091] The central convex portion 62 of the washer member 60 is inserted in a liquid-tight manner into the central hole portion 46 of the wall portion 44 of the adapter member 40. Further, the first member 11a of the shaft member 11 is inserted in a liquid-tight manner into the central hole 63 of the central convex portion 62. Thus, the outer peripheral portion of the first member 11a of the shaft member 11 provided with the strain gauge 16 is not in contact with the fluid being conveyed flowing through the suction port 32, the pump chamber 31, and the discharge port 33 because it is provided at a position rearward of the central hole 63 of the central convex portion 62 of the washer member 60.

[0092] [Structure of the diaphragm]

[0093] The diaphragm 50 is connected to the first member 11a of the shaft member 11 inserted into the central hole 63 of the central convex portion 62 of the washer member 60 by the insertion bolt 52. The diaphragm 50 is an elastic member in which, for example, the insertion bolt 52 connected to the first member 11a is integrally formed inside a resin such as ethylene propylene rubber (EPDM) and polytetrafluoroethylene (PTFE).

[0094] The diaphragm 50 is driven by the drive mechanism 10 housed in the front housing 26 of the pump main body 20 so as to be displaced along the reciprocating motion direction RD to change the volume of the pump chamber 31 of the pump head 30. The diaphragm 50 is installed in a liquid-tight manner in a state where the fixing portion 51 is clamped between the pump head 30 and the annular convex portion 43 of the adapter member 40 as described above and the front side of the central portion 53 faces the pump chamber 31. It should be noted that, for example, a holder member 54 for maintaining the shape of the diaphragm 50 and holding the position of the diaphragm 50 is provided between the front end of the diaphragm 50 and the first member 11a of the shaft member 11.

[0095] In the pump device 100 configured as described above, for example, when it is necessary to replace the strain gauge 16, the pump head 30, the diaphragm 50, and the adapter member 40 can be removed from the pump main body 20, the connector 16b can be removed from the relay connector 16c, and then the strain gauge 16 can be replaced together with the first member 11a of the shaft member 11. Therefore, a structure is achieved in which the replacement operation of the strain gauge 16 and the maintenance operation on the pump head 30 side can be easily performed.

[0096] [Circuit structure of the pump device]

[0097] As Figure 3As shown in the figure, the circuit structure of the pump device includes: a plurality of strain gauges 16 (resistors R1, R2), a sensor substrate 29a, and a control substrate 29. The sensor substrate 29a includes: resistors R3, R4 that form a bridge circuit 71 together with the plurality of strain gauges 16 (resistors R1, R2); a differential amplifier circuit 72 that includes an operational amplifier 72a and a plurality of resistors R5, R6, R7, R8 connected thereto. The control substrate 29 includes a control unit 73, an inference unit 74, and a storage unit 75.

[0098] Each of the circuits 71, 72 of the sensor substrate 29a is appropriately designed according to various data and conditions such as various main specifications of the pump device 100. Each of the parts 73 to 75 of the control substrate 29 is appropriately constituted according to a combination of known hardware such as a CPU, a RAM, and a ROM.

[0099] The bridge circuit 71 includes a strain gauge 16 as resistor R1 and a strain gauge 16 as resistor R2 provided on adjacent sides of the bridge, and resistors R3, R4 as two fixed resistors, and is configured to be able to further reduce the apparent strain caused by temperature.

[0100] The differential amplifier circuit 72 is configured to be able to amplify the output (detection signal of the amount of strain) from the bridge circuit 71 to a specified value, remove noise, and perform temperature compensation by appropriately adjusting the values of the four resistors R5 to R8 connected to the operational amplifier 72a.

[0101] Therefore, the detection signal of the strain gauge 16 output from the bridge circuit 71 when the pump device 100 is operating is amplified and noise is removed in the differential amplifier circuit 72 after temperature compensation, and can be input to the inference unit 74 as waveform data representing the amount of strain of the outer peripheral portion of the first component 11a of the shaft component 11.

[0102] The inference unit 74 infers the flow rate or pressure of the fluid being transported in the pump device 100 based on the input waveform data. That is, the flow rate and pressure of the fluid being transported by the pump device 100 vary with the load. The pressure change inside the pump head 30 (for example, inside the pump chamber 31) generated when the pump device 100 is operating is applied to the shaft component 11 as a load change through the diaphragm 50. Therefore, a strain proportional to the load is generated.

[0103] The generated strain is detected by the strain gauge 16, and thus the inference unit 74 infers the flow rate or pressure of the fluid being transported in the pump device 100 based on the waveform data representing the amount of strain output via the bridge circuit 71 and the differential amplifier circuit 72.

[0104] On the other hand, based on the flow rate inference result obtained by the inference unit 74, the control unit 73 controls the operation of the drive mechanism 10 so that the actual flow rate (actual flow rate) of the fluid being conveyed becomes, for example, a preset set flow rate. It should be noted that the storage unit 75 stores, for example, information (actual flow rate ratio data) related to the flow rate decrease rate or actual flow rate ratio relative to the potential difference of the waveform data indicating the strain amount at each number of strokes per minute (spm: strokes per minute) of the shaft member 11, which is obtained through pre-measurement or the like. The inference unit 74 infers the actual flow rate of the pump device 100 with reference to the actual flow rate ratio data stored in the storage unit 75.

[0105] In addition, when inhaling gas, when the gas is inhaled into the pump chamber 31, since the gas is compressed, the rise of the waveform data indicating the strain amount will be delayed. Therefore, the inference unit 74 sets a threshold value for the output value after a certain time (after a specified time) from the start of the rise of the waveform data to grasp the gas inhalation state.

[0106] In this way, based on the inferred actual flow rate, the inference unit 74 can further infer the operating state of the pump device 100, for example: to what extent the actual flow rate is operating relative to the set flow rate, or whether the operating state is abnormal, etc. Then, the control unit 73 can perform an operation for flow rate correction to make the actual flow rate of the fluid being conveyed become the set flow rate, for example, using the above actual flow rate ratio data, etc., and make the drive mechanism 10 operate in a manner to correct the flow rate. It should be noted that the display unit 28a in the operation unit 28 can visually display the notification information related to the operating state of the pump device 100 inferred by the inference unit 74 for the operator.

[0107] Figure 4 and Figure 5 is a graph showing the inferred flow rate and the actually measured flow rate of the pump device 100. Figure 4 The set flow rate is set to 60 [L / H]. Figure 5 The set flow rate is set to 1.0 [L / H], and then the vertical axis represents the flow rate [L / H] and the horizontal axis represents the pressure [MPa].

[0108] As Figure 4 the curves 77a and Figure 5As shown by curve 77b, whether the set flow rate is 60 [L / H] or 1.0 [L / H], in either case, when the pressure of the pump increases, a tendency for the flow rate to decrease is shown. The approximate curve 77c of the inferred flow rate, represented by a dashed line in the figure, depicts almost the same curve shape as the approximate curve 77d of the actual flow rate represented by a solid line. By calculating and comparing the results of the inferred flow rate and the actual flow rate thus represented, the error of the inferred flow rate relative to the actual flow rate is within ±2.08 [%RS] in terms of the scale accuracy, so it is shown that the inference unit 74 can perform flow rate inference with high accuracy. Here, as described above, there is a great correlation between the pressure of the pump and the strain amount.

[0109] Figure 6 is a graph showing the inhalation period and the discharge period of the pump device 100 and the strain amount waveform data. Figure 7 is a diagram showing an example of the data stored in the storage unit 75 of the pump device 100, showing an example of the actual flow rate ratio data representing the flow rate decrease rate, which is obtained by pre-measurement in the pump device 100 connected under specified pipeline conditions.

[0110] As Figure 6 shown, the high-level square wave U represents the inhalation period during which the pump device 100 is inhaling the transport fluid, and the low-level square wave D represents the discharge period during which the pump device 100 is discharging the transport fluid. This is obtained, for example, from a sensor cam signal (not shown). On the other hand, the waveform data W shows the output waveform of the differential amplifier circuit 72, which represents, for example, the strain amount obtained by detecting the stress change of the shaft member 11 of the pump device 100 with the strain gauge 16. The higher the level, the more it indicates that the shaft member 11 is in a state of bearing a load (a state where the load of the pump device 100 is higher). This waveform data W has the characteristic that its shape and the magnitude of the level change according to the pressure value of the transport fluid.

[0111] According to this Figure 6 it can be seen that during the inhalation period of the transport fluid represented by the square wave U, since the shaft member 11 is pulled back and the load applied to the shaft member 11 decreases, the waveform data W drops sharply and the level decreases. On the other hand, it can be seen that during the discharge period of the transport fluid represented by the square wave D, since the shaft member 11 is pushed forward and the load applied to the shaft member 11 increases over time, the waveform data W rises more slowly and the level becomes higher compared to the above-mentioned decrease.

[0112] Then, for example, by inferring and obtaining the potential difference PD of the drive mechanism 10 from the waveform data W, where the potential difference PD is represented by the level position D1 of the waveform data W at the end period of the square wave D in a certain cycle and the level position D2 of the waveform data W at the start period of the next cycle of the square wave D, the pressure of the fluid being conveyed can be recognized as the potential difference PD. It should be noted that although in this embodiment, in order to exclude the influence of noise from the "potential difference [V] of the waveform data representing the dependent variable" which is an input variable of the inference unit 74, the average value of the potential differences PD of 3 samples is used, the number of samples for obtaining the average value can be more or less.

[0113] In Figure 7 the actual flow rate ratio data 78 representing the flow rate decrease rate, the row elements represent, for example, a plurality of potential differences [V] calculated based on the potential differences PD of 3 samples under a certain operating condition (stroke number), and the column elements represent, for example, a plurality of stroke numbers [spm] set in 9 resolution levels, and correspondingly represent the values of the flow rate decrease rate corresponding to them.

[0114] It should be noted that the stroke number [spm] corresponds to the set flow rate [L / H]. In this example, the stroke numbers [spm] are 0.9 - 3.6, 3.6 - 9.0, 9.0 - 18.0, 18.0 - 36.0, 36.0 - 72.0, 72.0 - 108, 108 - 144, 144 - 180, 180 - respectively corresponding to the set flow rates [L / H] of 0.3 - 1.2, 1.2 - 3.0, 3.0 - 6.0, 6.0 - 12.0, 12.0 - 24.0, 24.0 - 36.0, 36.0 - 48.0, 48.0 - 60.0, 60.0 - respectively.

[0115] As Figure 7 shown, according to the actual flow rate ratio data 78 representing the flow rate decrease rate, for example, when the potential difference [V] is greater than 0.10 and less than 0.35, in any case where the stroke number [spm] is 0.9 - 180, the flow rate decrease rate is 0.00 (%), so it can be inferred that the actual flow rate remains the set flow rate.

[0116] On the other hand, as the potential difference [V] gradually increases from 0.35 - 0.60, 0.60 - 0.85,..., to greater than 2.70, the flow rate decrease rate at each stroke number [spm] gradually decreases. The flow rate decrease rate is the largest in the range where the maximum stroke number [spm] is greater than 180, and the flow rate decrease rate at this time is 23.68%.

[0117] Then, the inference unit 74 inputs the potential difference [V] and the flow rate set value [L / H] (set stroke number [spm]) as input variables, and based on what is stored in the storage unit 75 as Figure 7From the table shown, infer the actual flow rate.

[0118] Figure 8 FIG. is a diagram showing a display example in a display unit of a pump device.

[0119] As Figure 8 As shown, the display unit 28a included in the operation unit 28 is provided with: a first flow rate display area 28b that displays, for example, the flow rate inferred by the inference unit 74 as described above (and the actual flow rate calculated by arithmetic operation); and a second flow rate display area 28c that displays the set flow rate preset by an operator or the like. In the display unit 28a, since the inferred flow rate and the set flow rate are shown side by side in a manner that can be easily visually confirmed like this, the operator can easily grasp the operating state of the pump device 100.

[0120] It should be noted that the inference unit 74 can, for example, perform arithmetic processing so that the number of strokes [spm] becomes the magnification after adding the flow rate decrease rate by 100 (flow rate decrease rate + 100 (%)), and cause the control unit 73 to control the operation of the drive mechanism 10 so as to correct the flow rate of the component reduced based on the set flow rate and make it the set flow rate again.

[0121] In addition, as described above, the inference unit 74 detects the pressure of the fluid to be transported based on the waveform data representing the strain amount. For example, when the output value of the waveform data representing the strain amount is greater than a specified threshold value after a certain time has elapsed since the start time of the suction period of the pump device 100, or when the output value of the waveform data representing the strain amount is less than the specified threshold value after a certain time has elapsed since the start time of the discharge period, it is inferred that the operating state of the pump device 100 is abnormal. In addition, the inference unit 74 can also, for example, pay attention to whether the waveform shape of the waveform data from the rising position to the peak position is delayed compared to normal operation. Suppose that in the case where the waveform shape is a special shape that is more significantly delayed than normal operation from the start time of the discharge period shown by the square wave D, etc., indicating the operating state, it can also be inferred that a gas suction state has occurred and the operating state of the pump device 100 is abnormal operation. In these cases, notification information notifying such a situation can also be displayed on the display unit 28a.

[0122] In this way, the pump device 100 according to the present embodiment can infer the flow rate and pressure of the fluid to be transported by the pump device 100 based on the strain amount of the shaft member 11 detected by the strain gauge 16. As a result, a cheap structure can be obtained, and the flow rate and operating state can be simply inferred without being affected by the characteristics of the fluid to be transported and the pipeline conditions, and the correction of the flow rate and the inference of abnormal operation can also be easily performed.

[0123] [Second Embodiment]

[0124] Figure 9This is a cross-sectional view schematically showing the installation position of the sensor unit in the pump device according to the second embodiment of the present invention. It should be noted that hereinafter, repeated descriptions of parts that have been described will be omitted.

[0125] As Figure 9 shown, in the pump device 100A according to the second embodiment, for example, a strain gauge 16 as a sensor unit is provided on the front 30c side of a reinforcement plate 30a mounted on the front side of the pump head 30, which is a non-contact part for conveying fluid. In this regard, it is different from the first embodiment. With this structure, the load of the pump device 100A can also be detected by the strain gauge 16 in terms of the amount of strain, so the same effects as those of the first embodiment can be achieved.

[0126] [Third Embodiment]

[0127] Figure 10 This is a cross-sectional view schematically showing the installation position of the sensor unit in the pump device according to the third embodiment of the present invention.

[0128] As Figure 10 shown, in the pump device 100B according to the third embodiment, for example, a strain gauge 16 as a sensor unit is provided on the back (rear surface) 54a side of a holder member 54 provided on the back (rear side) of the diaphragm 50, which is a non-contact part for conveying fluid. In this regard, it is different from the first and second embodiments. With this structure, the load of the pump device 100B can also be detected by the strain gauge 16 in terms of the amount of strain, so the same effects as those of the first and second embodiments can be achieved.

[0129] [Fourth Embodiment]

[0130] Figure 11 This is a cross-sectional view schematically showing the installation position of the sensor unit in the pump device according to the fourth embodiment of the present invention.

[0131] As Figure 11 shown, in the pump device 100C according to the fourth embodiment, for example, a strain gauge 16 as a sensor unit is provided on the back (rear surface) 15a side of a bracket part 15 mounted on the front side of the drive mechanism 10, which is a non-contact part for conveying fluid. In this regard, it is different from the first to third embodiments. With this structure, the load of the pump device 100C can also be detected by the strain gauge 16 in terms of the amount of strain, so the same effects as those of the first to third embodiments can be achieved.

[0132] [Fifth Embodiment]

[0133] Figure 12It is a cross-sectional view schematically showing the installation position of the sensor unit in the pump device according to the fifth embodiment of the present invention.

[0134] As Figure 12 shown, in the pump device 100D according to the fifth embodiment, for example, a strain gauge 16 as a sensor unit is provided on the outer peripheral portion of the second member 11b of the shaft member 11, which is a non-contact portion for conveying fluid and is located on the rear side compared to the front surface of the support portion 15. In this regard, it is different from the first to third embodiments. With this structure, the load of the pump device 100D can also be detected by the strain gauge 16 in terms of the amount of strain, so the same effects as those of the first to fourth embodiments can be achieved.

[0135] [Sixth Embodiment]

[0136] Figure 13 It is a cross-sectional view schematically showing the installation position of the sensor unit in the pump device according to the sixth embodiment of the present invention.

[0137] As Figure 13 shown, in the pump device 100E according to the sixth embodiment, for example, a strain gauge 16 as a sensor unit is provided on the upper part of the drive mechanism 10 (for example, the upper surface 13d of the bearing portion 13c of the eccentric cam mechanism 13), which is a non-contact portion for conveying fluid. In this regard, it is different from the first to fifth embodiments. With this structure, the load of the pump device 100E can also be detected by the strain gauge 16 in terms of the amount of strain, so the same effects as those of the first to fifth embodiments can be achieved.

[0138] Several embodiments of the present invention have been described above, but these embodiments are presented as examples and are not intended to limit the scope of the invention. These new embodiments can be implemented in various other forms, and various omissions, substitutions, and changes can be made without departing from the gist of the invention. These embodiments and their modifications are included in the scope and gist of the invention, and at the same time are included in the invention described in the patent claims and its equivalent scope.

[0139] For example, in the above-described first embodiment, the strain gauge 16 is provided on the outer peripheral portion of the first member 11a of the shaft member 11, while in the second to sixth embodiments, the strain gauge 16 is provided at a non-contact portion for conveying fluid different from that of the first embodiment. In addition, the strain gauge 16 may be combined and provided at the installation positions of the non-contact portions shown in the first to sixth embodiments. The position of the strain gauge 16 can be set at various positions as long as it can detect the load of the pump device in terms of the amount of strain at the installation position, where the installation position is a non-contact portion for conveying fluid, so it is not limited to the above-described installation method.

Claims

1. A pump device, characterized in that: have: A pump head having a suction port and a discharge port for conveying fluid, a diaphragm attached to the pump head and forming a pump chamber connecting the suction port and the discharge port; as well as The pump body comprises: a reciprocating member connected to the diaphragm and arranged to be movable along the reciprocating direction of the diaphragm, a driving mechanism capable of driving the reciprocating member along the reciprocating direction of the diaphragm, and a control unit for controlling the driving mechanism. Among them, it also has: a sensor portion provided at a portion of the pump device that is not in contact with the conveying fluid and that detects strain generated at the non-contact portion when the pump device is operated; and An estimating unit estimates an actual flow rate of the conveying fluid or a pressure of the conveying fluid in the pump device based on the strain amount of the non-contact portion detected by the sensor unit.

2. The pump device according to claim 1, characterized in that The control unit controls the operation of the driving mechanism based on the estimation result of the actual flow rate obtained by the estimation unit so that the actual flow rate of the conveying fluid becomes a preset set flow rate.

3. The pump device according to claim 2, characterized in that A storage unit is further included, the storage unit storing pre-made information at each stroke number of the reciprocating member, the information showing an actual flow rate ratio corresponding to a potential difference of the waveform data representing the strain amount, The estimation unit estimates the actual flow rate by referring to the information indicating the actual flow rate ratio in the storage unit based on the potential difference of the waveform data indicating the strain amount.

4. The pump device according to claim 3, characterized in that The control unit further includes a display unit that displays information on the estimated actual flow rate together with the set flow rate in a visually recognizable manner.

5. The pump device according to claim 1, characterized in that The inference unit infers that the operating state of the pump device is abnormal operation when the output value of the waveform data representing the strain amount after a specified time has passed from the start time of the suction period of the pump device is greater than a specified threshold value, or when the output value of the waveform data representing the strain amount after a specified time has passed from the start time of the discharge period of the pump device is less than a specified threshold value.

6. The pump device according to any one of claims 1 to 5, characterized in that The sensor portion is provided at the non-contact portion of the outer peripheral portion near a portion of the reciprocating member connected to the diaphragm.

7. The pump device according to any one of claims 1 to 5, characterized in that A plurality of the sensor parts are provided at the non-contact location.

8. The pump device according to any one of claims 1 to 5, characterized in that The sensor portion is arranged at the non-contact portion of at least one of the following portions: a reinforcing portion installed on the front side of the pump head, a fixing portion arranged on the back side of the diaphragm, a bracket portion installed on the front side of the driving mechanism, an outer peripheral portion of the reciprocating motion portion located further rearward than the front of the bracket portion, and an upper portion of the driving mechanism.

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