Reciprocating Pump

Abstract

To provide a reciprocation pump capable of more easily and accurately estimating the abrasion loss of a ware band.SOLUTION: A reciprocation pump includes: a pump body having a piston and a cylinder; and a drive part for making the piston reciprocate in a reciprocating direction. The drive part has: a drive part body having a disc-like rotary body and an eccentric shaft part provided on the surface of the rotary body; a cylindrical housing covering the drive part body from the outer peripheral side and extending in the reciprocating direction; a cross head movable forward and backward in the housing in the reciprocating direction; a link part connecting the rotary body to the cross head; and a ware band provided between the outer peripheral face of the cross head and an inner peripheral face of the housing, and further includes a plurality of first sensor parts provided outside the cylinder in the piston while being spaced from one another in the radial direction with respect to the reciprocating direction, for measuring the displacement in the radial direction of the piston.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to a reciprocating pump. [Background technology]

[0002] Reciprocating pumps have been used to compress liquid hydrogen. This type of pump is capable of pressurizing liquid hydrogen up to approximately 90 MPa, for example. Specifically, a reciprocating pump mainly comprises a piston that reciprocates in the axial direction and a cylinder that surrounds the piston. As the piston reciprocates within the cylinder, the liquid hydrogen is gradually compressed and discharged to the outside. The piston is driven by a drive unit. The drive unit has a cylindrical housing, a crosshead that can reciprocate within the housing, a rotor, and a link that converts the circular motion of the rotor into reciprocating motion.

[0003] Wear rings are sliding components that guide the piston within the cylinder. Wear rings are also installed in the sliding portion between the crosshead and the housing. Therefore, wear can occur in the wear rings over time. As wear in the wear ring progresses, there is a risk that the piston and the cylinder may come into contact. For this reason, there has been a growing demand for technology that can manage the progression of wear ring wear.

[0004] One example of this type of technology is the diagnostic method described in Patent Document 1 below. This diagnostic method is a technology for evaluating the amount of wear on a wear ring installed between the impeller and casing of a centrifugal pump. This method is said to be able to diagnose the degree of wear on the wear ring by comparing the planned values ​​and actual measured values ​​of the head and flow rate. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2014-202144 Summary of the Invention [Problem to be solved by the invention]

[0006] However, in order to obtain the planned and actual values ​​of the head and flow rate as described above, it is necessary to constantly acquire and analyze a large number of parameters, such as the pump's suction pressure and discharge pressure, the motor's voltage, current, efficiency, etc. For this reason, there is still room for improvement in the technology described in Patent Document 1.

[0007] The present disclosure has been made to solve the above-mentioned problems, and aims to provide a reciprocating pump that allows for easier and more accurate evaluation of the amount of wear of a wear band. [Means for solving the problem]

[0008] In order to solve the above-described problems, a reciprocating pump according to the present disclosure includes a pump main body having a piston that compresses a liquid and a cylinder that covers the piston from the outside, and a drive unit that reciprocates the piston in a reciprocating direction relative to the cylinder, wherein the drive unit includes a drive unit main body having a disk-shaped rotor centered on a central axis that extends in a direction intersecting the reciprocating direction and an eccentric shaft portion provided on a surface of the rotor, a cylindrical housing that covers the drive unit main body from the outer periphery and extends in the reciprocating direction, a crosshead that is movable back and forth in the reciprocating direction within the housing, a link portion that connects the rotor and the crosshead, and a wear band that is provided between the outer periphery of the crosshead and the inner periphery of the housing, and further includes a plurality of first sensors that are provided outside the cylinder of the piston at intervals in a radial direction relative to the reciprocating direction and that measure radial displacement of the piston. an acceleration sensor provided between the inner peripheral surface of the wear band and the outer peripheral surface of the crosshead; a self-power generating mechanism having a first member provided on the inner peripheral surface of the wear band and a second member provided on the outer peripheral surface of the crosshead and slidable against the first member, the first member sliding against the second member based on the reciprocating motion of the wear band, and supplying power to the acceleration sensor; Further provided are: [Effects of the Invention]

[0009] According to the present disclosure, it is possible to provide a reciprocating pump that allows for easier and more accurate evaluation of the amount of wear of a wear band. [Brief explanation of the drawings]

[0010] [Figure 1] 1 is a longitudinal cross-sectional view showing a configuration of a reciprocating pump according to a first embodiment of the present disclosure. [Figure 2] FIG. 2 is a cross-sectional view taken along line II-II in FIG. [Figure 3] FIG. 2 is a longitudinal cross-sectional view showing a modified example of the reciprocating pump according to the first embodiment of the present disclosure. [Figure 4] FIG. 4 is a longitudinal cross-sectional view showing the configuration of a reciprocating pump according to a second embodiment of the present disclosure. [Figure 5] FIG. 10 is an enlarged cross-sectional view of a main portion of a reciprocating pump according to a third embodiment of the present disclosure. [Figure 6] FIG. 10 is an enlarged cross-sectional view of a main portion of a reciprocating pump according to a fourth embodiment of the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0011] A reciprocating pump 100 according to an embodiment of the present disclosure will now be described with reference to FIGS. 1 and 2. FIG.

[0012] (Configuration of reciprocating pump) The reciprocating pump 100 is a device for pressurizing a cryogenic liquid, such as liquid hydrogen, to a high pressure (approximately 90 MPa). As shown in Fig. 1, the reciprocating pump 100 includes a piston 1, a cylinder 2, a drive unit 3, a casing 4, a check valve 5, a discharge pipe 6, a discharge valve 7, and a measurement unit 8. The piston 1 and the cylinder 2 constitute a pump body 9.

[0013] (Piston configuration) The piston 1 has a cylindrical piston body 10 centered on an axis O extending in the vertical direction, and a wear ring 11 and a piston ring 12 attached to the piston body 10. The radial dimension of the piston body 10 is constant throughout the entire area in the direction of the axis O. The wear ring 11 is provided at the tip of the piston body 10. The wear ring 11 has an annular shape centered on the axis O and is made of a resin material.

[0014] One wear ring 11 is provided at the lower end of the piston body 10, and another wear ring 11 is provided at a distance from the wear ring 11 in the direction of the axis O. A plurality of (for example, six) piston rings 12 are provided between the pair of wear rings 11 and arranged at intervals in the direction of the axis O. The wear ring 11 is provided to guide the piston body 10 along the inner circumferential surface of the cylinder 2, which will be described later. On the other hand, the piston ring 12 is provided to maintain liquid-tightness and air-tightness between the piston body 10 and the inner circumferential surface of the cylinder 2.

[0015] (Cylinder configuration) The cylinder 2 is cylindrical and has a bottom, covering the piston 1 from the outer periphery. The piston 1 is inserted into the cylinder 2 from an opening h at the top of the cylinder 2. The space inside the cylinder 2 below the tip of the piston 1 forms a compression chamber 21. A check valve 5 is provided at the bottom of the cylinder 2 to guide liquid hydrogen into the compression chamber 21. This check valve 5 is capable of allowing liquid hydrogen to flow only in the direction from outside the cylinder 2 toward the inside of the compression chamber 21. In other words, even if the pressure in the compression chamber 21 increases, liquid hydrogen will not flow out of the cylinder 2 through the check valve 5.

[0016] A discharge pipe 6 is connected to the side of the cylinder 2 facing the compression chamber 21. The discharge pipe 6 is provided to discharge the liquid hydrogen compressed in the compression chamber 21 to the outside of the cylinder 2. A discharge valve 7 is provided on this discharge pipe 6. The discharge valve 7 is capable of circulating liquid hydrogen only in the direction from the compression chamber 21 to the outside when the pressure inside the compression chamber 21 reaches or exceeds a predetermined value.

[0017] (Driver configuration) The piston 1 described above reciprocates in the direction of axis O when a driving force is applied by a driving unit 3 within a cylinder 2. The driving unit 3 has an eccentric shaft 31, a rotor 32, a link 33, a swing shaft 35, a crosshead 36, a housing 37, and a wear band 38. The eccentric shaft 31 and the rotor 32 constitute a driving unit main body 50.

[0018] The eccentric shaft portion 31 is driven to rotate around a rotation axis X (central axis) that extends in a horizontal direction perpendicular to the axis O by an electric motor (not shown). The eccentric shaft portion 31 is cylindrical and has a center on the rotation axis X. The rotating body 32 is provided integrally with the eccentric shaft portion 31 and has a disk shape that has a center on an axis different from the rotation axis X. In other words, the rotation axis X of the eccentric shaft portion 31 is provided at an eccentric position with respect to the center of the rotating body 32. When the eccentric shaft portion 31 is driven to rotate, the rotating body 32 revolves around the rotation axis X.

[0019] The link portion 33 is a member that converts the orbital motion of the rotor 32 into reciprocating motion in the direction of the axis O and transmits the motion to the piston. The link portion 33 has an upper annular portion 33a that is annular and covers the outer periphery of the rotor 32, a connecting portion 33b, and a lower annular portion 33c. A bearing device (not shown) is provided between the inner circumferential surface of the upper annular portion 33a and the outer circumferential surface of the rotor 32. The lower annular portion 33c is annular like the upper annular portion 33a and is integrally connected to the upper annular portion 33a by the connecting portion 33b. A swing shaft portion 35 is attached to the lower end of the lower annular portion 33c. A lower end of the swing shaft portion 35 is connected to the upper end of the piston 1. The swing shaft portion 35 is swingable around a swing axis that extends horizontally and is perpendicular to the axis O relative to the lower annular portion 33c.

[0020] The crosshead 36 is cylindrical with a bottom that covers the lower annular portion 33c from the outside. A housing 37 is provided on the outer periphery of the crosshead 36. When the link portion 33 reciprocates as the rotating body 32 turns, the outer periphery of the crosshead 36 reciprocates relative to the inner periphery of the housing 37. This direction may be simply referred to as the "reciprocating direction." The reciprocating direction is a direction that intersects with the above-mentioned rotation axis X. A wear band 38 is provided between the outer periphery of the crosshead 36 and the inner periphery of the housing 37. The wear band 38 is a member that has the same function and material as the above-mentioned wear ring 11.

[0021] (Casing configuration) The casing 4 is a container that covers the cylinder 2 from the outside. The casing 4 has a cylindrical casing main body 41 with a bottom, a supply pipe 42, and a gas discharge pipe 43. The supply pipe 42 is a pipe for guiding liquid hydrogen from an external supply source into the casing main body 41 (liquid storage chamber 44). The supply pipe 42 is provided near the bottom surface of the casing main body 41. The gas discharge pipe 43 is provided for discharging vaporized components (gas components) in the liquid storage chamber 44 to the outside. The gas discharge pipe 43 is provided at a position spaced above the supply pipe 42. The liquid level of the liquid hydrogen in the liquid storage chamber 44 is adjusted so that it is located below the gas discharge pipe 43. The discharge pipe 6 described above extends to the outside of the casing 4.

[0022] (Configuration of the measurement unit) The first sensor unit 81 serving as the measuring unit 8 is a non-contact sensor that detects the radial displacement of the piston body 10. Specifically, an optical or eddy current sensor is used as the first sensor unit 81. The first sensor unit 81 is disposed outside the cylinder 2 (i.e., above the opening of the cylinder 2) so as to face the piston body 10 in the radial direction. Two first sensor units 81 are provided circumferentially with a 90° interval around the axis O. One first sensor unit 81 is provided along the oscillating surface direction of the pivot shaft 35. That is, the one first sensor unit 81 measures the radial displacement of the piston 1 from the direction in which the load due to the pivoting of the pivot shaft 35 is applied to the piston 1. The other first sensor unit 81 measures the displacement of the piston 1 from a direction perpendicular to the one first sensor unit 81. The number of first sensor units 81 is not limited to two, and may be one, three, or more. Furthermore, the circumferential interval between the two first sensor portions 81 does not necessarily have to be exactly 90°, and manufacturing errors and the like are allowed.

[0023] (Action and effect) To operate the reciprocating pump 100, first, liquid hydrogen is supplied into the cylinder 2 through the supply pipe 42, and then the piston 1 is reciprocated within the cylinder 2 by the drive unit 3. This causes the liquid hydrogen within the cylinder 2 to be gradually compressed and reach a high pressure. The high-pressure liquid hydrogen is then discharged to the outside through the discharge pipe 6.

[0024] Here, if the reciprocating pump 100 is operated continuously for a long period of time, wear occurs in the sliding parts of the drive unit 3. Specifically, wear is likely to occur in the wear band 38 provided between the crosshead 36 and the housing 37 described above. Once the wear band 38 has worn to a certain extent, it is replaced. For this reason, it is necessary to monitor the degree of wear (amount of wear) of the wear band 38 and predict when it should be replaced. Therefore, the reciprocating pump 100 according to this embodiment employs the above-described configurations.

[0025] According to the above configuration, the relative displacement between the crosshead 36 and the housing 37 can be detected by measuring the radial displacement of the piston over a certain period of time using the first sensor unit 81. This makes it possible to know the progress of wear on the wear band 38. In particular, since the displacement of the piston 1 is measured outside the cylinder 2 near the wear band 38, the amount of wear of the wear band 38 can be detected more accurately.

[0026] Furthermore, with the above configuration, by measuring the displacement of the piston 1 from at least two directions spaced circumferentially at 90° intervals, the degree of wear on the wear band 38 can be detected with even greater accuracy. In particular, the piston 1 is primarily subjected to a load in the diameter direction associated with the rotation of the rotor 32. By measuring the displacement of the piston 1 in a direction along this load and in another direction perpendicular to it, the inclination of the piston can also be detected, ultimately enabling the degree of wear on the wear band 38 to be detected with greater accuracy.

[0027] The first embodiment of the present disclosure has been described above. Various changes and modifications can be made to the above configuration without departing from the spirit and scope of the present disclosure. For example, as shown in FIG. 3 , a modified example can be provided in addition to a first sensor unit 81. The second sensor unit 82 is a non-contact sensor capable of measuring radial displacement of the piston 1 inside the cylinder 2. This configuration allows the second sensor unit 82 to measure the displacement of the piston 1 inside the cylinder 2 in addition to the first sensor unit 81, thereby enabling the progress of wear of the wear band 38 to be detected with even greater accuracy. Similarly to the first sensor unit 81, it is also desirable to provide two second sensor units 82 spaced 90° apart in the circumferential direction.

[0028] Second Embodiment Next, a reciprocating pump 100 according to a second embodiment of the present disclosure will be described with reference to Fig. 4. Note that the same components as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof will be omitted.

[0029] 4, in this embodiment, a reservoir 60 is provided on the top surface of the casing body 41 in a region overlapping between the crosshead 36 and the housing 37. The reservoir 60 is an annular tray centered on the axis O, and is provided to collect wear powder generated as the wear band 38 wears.

[0030] (Action and effect) With the above configuration, the wear progress of the wear band 38 can be visually and quantitatively evaluated based on the amount of wear debris accumulated in the reservoir 60. For example, the amount of wear can be quantitatively evaluated based on the weight of the wear debris. Furthermore, it is possible to prevent the surrounding area from being soiled by the scattering of wear debris. This also makes it possible to avoid malfunctions of the device caused by wear debris getting into unexpected places.

[0031] The second embodiment of the present disclosure has been described above. Various changes and modifications can be made to the above configuration without departing from the spirit and scope of the present disclosure. For example, while the example of FIG. 4 shows a configuration including a first sensor unit 81 and a second sensor unit 82, it is also possible to provide only the first sensor unit 81.

[0032] Third Embodiment Next, a third embodiment of the present disclosure will be described with reference to Fig. 5. Note that the same components as those in the above embodiments are denoted by the same reference numerals, and detailed description thereof will be omitted.

[0033] 5, the reciprocating pump 100 according to this embodiment further includes an optical fiber 70, an irradiation unit 71, and a determination unit 72. The optical fiber 70 is embedded in the wear band 38 over multiple paths. It is also possible to embed a single optical fiber 70 in the wear band 38 so that it spirals around the wear band 38.

[0034] The irradiation unit 71 is a light source that irradiates one end of the optical fiber 70 with light to generate light that is emitted from the other end of the optical fiber 70. The determination unit 72 is a device that determines the degree of wear of the wear band 38 based on the properties of the emitted light (for example, the intensity and brightness of the light). Note that a photometer or the like is preferably used as the determination unit 72.

[0035] (Action and effect) According to the above configuration, since the optical fiber 70 is embedded in the wear band 38, as the wear band 38 wears, the optical fiber 70 becomes exposed toward the crosshead 36, causing a change in cross-sectional shape. Therefore, the characteristics of the emitted light that passes through the other end of the optical fiber 70 after repeatedly reflecting within the optical fiber 70 also change. By evaluating this characteristic using the determination unit 72, the degree of wear of the wear band 38 can be detected accurately and easily. Furthermore, because the optical fiber 70 is made of a resin material like the wear band 38, it is unlikely to damage the housing 37 or the crosshead 36. In other words, measuring the degree of wear of the wear band 38 is unlikely to affect the normal operating conditions of the device. This allows the reciprocating pump 100 to operate stably for an even longer period of time.

[0036] The third embodiment of the present disclosure has been described above. Note that various changes and modifications can be made to the above configuration without departing from the gist of the present disclosure.

[0037] <Fourth embodiment> Next, a fourth embodiment of the present disclosure will be described with reference to Fig. 6. Note that the same components as those in the above embodiments are denoted by the same reference numerals, and detailed description thereof will be omitted.

[0038] 6, in this embodiment, an acceleration sensor 73 is provided between the inner circumferential surface of the wear band 38 and the outer circumferential surface of the crosshead 36. The acceleration sensor 73 may be fixed to the wear band 38 or to the crosshead 36. The acceleration sensor 73 detects changes in acceleration accompanying the reciprocating movement of the crosshead 36.

[0039] Furthermore, a self-power generating mechanism 76 is provided between the wear band 38 and the crosshead 36 to supply power to the acceleration sensor 73. The self-power generating mechanism 76 is based on a known power generation technology that generates power through friction, for example. The self-power generating mechanism 76 has a first member 74 provided on the inner circumferential surface of the wear band 38 and a second member 75 provided on the outer circumferential surface of the crosshead 36. The sliding contact between the first member 74 and the second member 75 generates an induced electromotive force, which is supplied to the acceleration sensor 73. This power operates the acceleration sensor 73.

[0040] (Action and effect) When the wear band 38 wears, the shape changes, causing the direction of reciprocation of the crosshead 36 to change slightly. In other words, the ratio of the directional components of the acceleration of the crosshead 36 changes. With the above configuration, the change in acceleration of the crosshead 36 that occurs as the wear band 38 wears can be measured by the acceleration sensor 73, making it possible to evaluate the degree of wear of the wear band 38. Furthermore, since the self-power generation mechanism 76 is included, there is no need to supply a separate external power source. This also prevents a decrease in the operating efficiency of the entire device. Therefore, the reciprocating pump 100 can be operated stably for an even longer period of time.

[0041] The fourth embodiment of the present disclosure has been described above. Note that various changes and modifications can be made to the above configuration without departing from the gist of the present disclosure.

[0042] <Additional Notes> The reciprocating pump described in each embodiment can be understood, for example, as follows.

[0043] (1) A reciprocating pump 100 according to a first aspect includes a pump body 9 having a piston 1 for compressing a liquid and a cylinder 2 that covers the piston 1 from the outside, and a drive unit 3 that reciprocates the piston 1 in a reciprocating direction relative to the cylinder 2. The drive unit 3 includes a drive unit body 50 having a disk-shaped rotor 32 centered on a central axis (rotation axis X) that extends in a direction intersecting the reciprocating direction and an eccentric shaft portion 31 provided on the surface of the rotor 32, and a rotor 50 that covers the outer periphery of the drive unit body 50 and reciprocates the piston 1 in the reciprocating direction relative to the cylinder 2. a cylindrical housing 37 extending in a direction perpendicular to the axis of rotation of the piston 1; a crosshead 36 movable back and forth within the housing 37; a link portion 33 connecting the rotating body 32 and the crosshead 36; and a wear band 38 provided between the outer peripheral surface of the crosshead 36 and the inner peripheral surface of the housing 37. The piston 1 further includes a plurality of first sensor portions 81 provided outside the cylinder 2 of the piston 1 at intervals in a radial direction relative to the reciprocating direction and for measuring radial displacement of the piston 1.

[0044] According to the above configuration, the relative displacement between the crosshead 36 and the housing 37 can be detected by measuring the radial displacement of the piston over a certain period of time using the first sensor unit 81. This makes it possible to know the progress of wear on the wear band 38.

[0045] (2) A reciprocating pump 100 according to a second aspect is the reciprocating pump 100 of (1), wherein the plurality of first sensor parts 81 are arranged at intervals of 90° in the circumferential direction.

[0046] According to the above configuration, by measuring the displacement of the piston from at least two directions at 90° intervals in the circumferential direction, the progress of wear of the wear band 38 can be detected with even greater accuracy.

[0047] (3) The reciprocating pump 100 according to the third aspect is the reciprocating pump 100 of (1) or (2), further comprising a plurality of second sensor units 82 arranged inside the cylinder 2 of the piston 1 at intervals in the radial direction relative to the reciprocating direction, and measuring the radial displacement of the piston 1.

[0048] According to the above configuration, in addition to the first sensor unit 81, the second sensor unit 82 measures the displacement of the piston 1 inside the cylinder 2, thereby making it possible to detect the degree of wear of the wear band 38 with even greater accuracy.

[0049] (4) A reciprocating pump 100 according to a fourth aspect is a reciprocating pump 100 according to any one of aspects (1) to (3), in which the plurality of second sensor parts 82 are arranged at 90° intervals in the circumferential direction.

[0050] According to the above configuration, by measuring the displacement of the piston 1 from at least two directions at 90° intervals in the circumferential direction, the progress of wear of the wear band 38 can be detected with even higher accuracy.

[0051] (5) The reciprocating pump 100 according to the fifth aspect is a reciprocating pump 100 according to any one of aspects (1) to (4), and further includes a storage section 60 provided below the housing 37 and capable of storing wear powder from the wear band 38.

[0052] According to the above configuration, the degree of wear of the wear band 38 can be visually and quantitatively evaluated from the amount of wear debris accumulated in the reservoir 60.

[0053] (6) The reciprocating pump 100 according to the sixth aspect is a reciprocating pump 100 according to any one of the aspects (1) to (5), and further includes an optical fiber 70 embedded inside the wear band 38, an irradiation unit 71 that transmits light to the optical fiber 70, and a determination unit 72 that receives the emitted light after passing through the optical fiber 70 and determines the amount of wear of the wear band 38 based on the properties of the emitted light.

[0054] According to the above configuration, since the optical fiber 70 is embedded in the wear band 38, when the wear band 38 wears, the optical fiber 70 becomes exposed, for example, and the cross-sectional shape changes. This causes a change in the properties of the emitted light that passes through the optical fiber 70. By evaluating this property using the determination unit 72, the degree of wear of the wear band 38 can be detected accurately and easily.

[0055] (7) A reciprocating pump 100 according to a seventh aspect is a reciprocating pump 100 according to any one of the aspects (1) to (6), further comprising an acceleration sensor 73 provided between the inner circumferential surface of the wear band 38 and the outer circumferential surface of the crosshead 36, a first member 74 provided on the inner circumferential surface of the wear band 38, and a second member 75 provided on the inner circumferential surface of the crosshead 36 and slidable against the first member 74, and a self-generating mechanism 76 that supplies power to the acceleration sensor 73 by sliding the first member 74 and the second member 75 based on the reciprocating motion of the crosshead 36.

[0056] With the above configuration, the change in acceleration of the crosshead 36 that occurs as the wear band 38 wears can be measured by the acceleration sensor 73, making it possible to evaluate the degree of wear of the wear band 38. Furthermore, since the device has a self-power generating mechanism 76, there is no need to supply a separate external power source. This also makes it possible to avoid a decrease in the operating efficiency of the entire device. [Explanation of symbols]

[0057] 100 Reciprocating Pump 1 piston 2 cylinders 3 Drive unit 4 Casing 5. Check valve 6 Discharge piping 7. Discharge valve 8. Measurement section 9 Pump body 10 Piston body 11 Wearing 12 Piston rings 21 Compression chamber 31 Eccentric shaft part 32 Rotating body 33 Link section 33a Upper annular part 33b Connection 33c Lower annular part 35 Swing shaft 36 Crosshead 37 Housing 38 Wear Band 41 Casing body 42 Supply pipe 43 Gas exhaust pipe 44 Liquid storage chamber 50 Drive unit body 60 Storage section 70 Optical Fiber 71 Irradiation unit 72 Judgment section 73 Acceleration Sensor 74 First member 75 Second member 76 Self-powered mechanism 81 First sensor part 82 Second sensor part h opening O axis X rotation axis

Claims

1. a pump body having a piston for compressing a liquid and a cylinder for covering the piston from the outside; a drive unit that reciprocates the piston in a reciprocating direction relative to the cylinder; Equipped with The drive unit is a drive unit main body having a disk-shaped rotor centered on a central axis extending in a direction intersecting the reciprocating direction, and an eccentric shaft portion provided on a surface of the rotor; a cylindrical housing that covers the drive unit body from an outer periphery side and extends in the reciprocating direction; a crosshead that is movable back and forth in the reciprocating direction within the housing; a link portion connecting the rotating body and the crosshead; a wear band provided between an outer peripheral surface of the crosshead and an inner peripheral surface of the housing; and The piston further includes a plurality of first sensor units provided at intervals in a radial direction relative to the reciprocating direction on the outside of the cylinder, the first sensor units measuring a radial displacement of the piston, an acceleration sensor provided between an inner peripheral surface of the wear band and an outer peripheral surface of the crosshead; a self-power generating mechanism including a first member provided on an inner peripheral surface of the wear band and a second member provided on an outer peripheral surface of the crosshead and capable of sliding with the first member, the first member sliding with the second member based on the reciprocating motion of the wear band, thereby supplying power to the acceleration sensor; The reciprocating pump further comprises:

2. The reciprocating pump according to claim 1 , wherein the plurality of first sensor units are arranged at intervals of 90° in the circumferential direction.

3. 3. The reciprocating pump according to claim 1, further comprising a plurality of second sensor units arranged inside the cylinder of the piston at intervals in a radial direction relative to the reciprocating direction, and configured to measure radial displacement of the piston.

4. The reciprocating pump according to claim 3 , wherein the second sensor units are arranged at 90° intervals in the circumferential direction.

5. 2. The reciprocating pump according to claim 1, further comprising a reservoir provided below the housing and capable of storing wear powder from the wear band.

6. an optical fiber embedded inside the wear band; an irradiation unit that transmits light to the optical fiber; a determination unit that receives the emitted light after passing through the optical fiber and determines the wear amount of the wear band based on the properties of the emitted light; The reciprocating pump of claim 1 further comprising:

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