Foreign substance sensing device

Abstract

A foreign substance sensing device according to one embodiment of the present invention comprises: a pipe along which a fluid passes; electrodes disposed to surround the pipe; and a foreign substance detection sensor that senses, by means of the electrodes, a change in capacitance caused by foreign substances in the fluid passing along the pipe. As the electrodes, a positive electrode and a negative electrode may be alternately disposed along the circumference of the pipe.

Description

Foreign body detection device

[0001] Cross-citation with related application(s)

[0002] This application claims the benefit of priority to Korean Patent Application No. 10-2024-0119985, filed September 4, 2024, the entire contents of which are incorporated herein by reference.

[0003] The present invention relates to a foreign substance detection device, and more specifically, to a foreign substance detection device capable of accurately measuring a foreign substance by accurately measuring a change in electrostatic capacitance regardless of which part of a measurement pipe the foreign substance passes through.

[0004] In modern society, the widespread use of portable devices like cell phones, laptops, camcorders, and digital cameras, as well as energy storage systems (ESS), has led to active development of related technologies. Furthermore, rechargeable secondary batteries are increasingly being used as power sources for electric vehicles (EVs), hybrid electric vehicles (HEVs), and plug-in hybrid electric vehicles (P-HEVs) to address air pollution issues caused by conventional gasoline-powered vehicles. This, in turn, heightens the need for further development of these batteries.

[0005] Currently commercialized secondary batteries include nickel-cadmium batteries, nickel-hydrogen batteries, nickel-zinc batteries, and lithium secondary batteries. Among these, lithium secondary batteries are receiving the most attention due to their advantages of free charging and discharging, low self-discharge rate, and high energy density.

[0006] These lithium secondary batteries primarily use lithium oxide and carbon materials as the positive and negative electrode active materials, respectively. Lithium secondary batteries comprise an electrode assembly comprising positive and negative plates coated with the positive and negative electrode active materials, respectively, with a separator interposed between them, and an outer case, i.e., a battery case, that seals and encloses the electrode assembly together with an electrolyte.

[0007] These secondary batteries are widely used not only in small devices like portable electronic devices, but also in medium- to large-scale devices like electric vehicles and energy storage systems (ESS), and their use is rapidly increasing. Furthermore, the use of residential battery packs for power storage has been on the rise recently.

[0008] Foreign matter, especially metallic particles, can cause numerous problems during the secondary battery manufacturing process. Metallic particles can cause low voltages in batteries and ultimately lead to battery failure. Metallic particles can be present not only in the raw materials themselves, but also in facilities associated with the secondary battery manufacturing process. Therefore, it is necessary to measure the presence of metallic particles from all sources throughout the secondary battery manufacturing process.

[0009] However, since the shape of the sensor for measuring foreign substances is conventionally flat, there is a problem that the accuracy of measuring foreign substances varies depending on the distance between the foreign substance and the sensor.

[0010] The problem to be solved by the present invention is to provide a foreign substance detection device capable of accurately measuring a foreign substance by accurately measuring a change in electrostatic capacitance regardless of which part of the measurement pipe the foreign substance passes through.

[0011] However, the problems to be solved by the embodiments of the present invention are not limited to the problems described above and can be expanded in various ways within the scope of the technical ideas included in the present invention.

[0012] A foreign substance detection device according to one embodiment of the present invention includes a pipe through which a fluid passes, electrodes arranged to surround the periphery of the pipe, and a foreign substance detection sensor that senses a change in electrostatic capacity caused by foreign substances in the fluid passing through the pipe through the electrodes, wherein the electrodes may be arranged with anodes and cathodes alternately along the periphery of the pipe.

[0013] The above electrode may have an interdigitated structure.

[0014] The above foreign substance detection device further includes an inlet through which the fluid flows, and the fluid flowing through the inlet can flow into the pipe.

[0015] The above inlet may be a variable inlet in which the cross-sectional area through which the fluid flows in can be changed.

[0016] The variable inlet may include an aperture portion whose cross-sectional area is variable between a first area and a second area.

[0017] The above aperture portion may include a support plate having an open center, a plurality of blades rotatably coupled to the support plate, a rotation plate having an open center and supporting the plurality of blades together with the support plate, and a guide portion guiding the rotation of the plurality of blades.

[0018] The above guide portion may include a guide groove formed in one of the blades and the rotation plate to guide rotation of the plurality of blades, and a guide protrusion formed in the other of the blades and the rotation plate and inserted into the guide groove.

[0019] The variable inlet port may include a head portion detachably coupled to the inlet port, and the head portion may include a coupling portion coupled to the inlet port and an inlet portion through which the fluid flows and which has a cross-sectional area different from that of the inlet port.

[0020] The head portion may further include an enlarged portion whose cross-sectional area increases as it moves from the coupling portion toward the inlet portion, or a reduced portion whose cross-sectional area decreases as it moves from the coupling portion toward the inlet portion.

[0021] The electrode may include a first electrode and a second electrode disposed downstream of the first electrode, and the foreign substance detection sensor may include a first foreign substance detection sensor that measures a change in electrostatic capacity caused by the foreign substance in the fluid passing through the pipe through the first electrode, and a second foreign substance detection sensor that measures a change in electrostatic capacity caused by the foreign substance in the fluid passing through the pipe through the second electrode.

[0022] The size of the foreign substance measurable through the first foreign substance detection sensor and the size of the foreign substance measurable through the second foreign substance detection sensor may be different from each other.

[0023] The thickness of the first anode and the first cathode of the first electrode may be different from the thickness of the second anode and the second cathode of the second electrode.

[0024] The spacing between the first anode and the first cathode of the first electrode may be different from the spacing between the second anode and the second cathode of the second electrode.

[0025] The first voltage applied to the first electrode and the second voltage applied to the second electrode may be different from each other.

[0026] The first area of ​​the pipe where the first electrode is placed and the second area of ​​the pipe where the second electrode is placed may be different from each other.

[0027] The foreign substance detection device further includes a processor that detects the foreign substance passing through the pipe through electrical signals generated from the first foreign substance detection sensor and the second foreign substance detection sensor, and the processor can calculate a ratio of the amount of the foreign substance detected through the first electrode and the amount of the foreign substance detected through the second electrode.

[0028] The foreign substance detection device further includes a pump for sucking the fluid into the pipe and a filter member for filtering the fluid passing through the electrode, and the pump may be located downstream of the filter member.

[0029] The above foreign substance detection device may further include a shielding member disposed outside the electrode.

[0030] The above shielding member is formed of metal, and the above shielding member can be electrically connected to an external ground.

[0031] The above fluid may be air within a secondary battery manufacturing facility.

[0032] The foreign substance detection device according to embodiments of the present invention can accurately measure foreign substances by accurately measuring changes in electrostatic capacitance regardless of which part of the measurement pipe the foreign substance passes through.

[0033] Additionally, the foreign matter detection device includes a first foreign matter detection sensor and a second foreign matter detection sensor, each measuring different sizes of measurable foreign matter, enabling the ratio of small to large foreign matter to be calculated. This allows for flexible responses, such as establishing stronger countermeasures when a high ratio of large foreign matter is measured from a specific foreign matter source.

[0034] The effects of the present invention are not limited to the effects mentioned above, and other effects not mentioned will be clearly understood by those skilled in the art from the description of the claims.

[0035] FIG. 1 is a schematic diagram of a foreign substance detection device according to one embodiment of the present invention.

[0036] Figure 2 is a drawing for explaining the process of detecting a foreign substance by the foreign substance detection device illustrated in Figure 1.

[0037] Figure 3 is a cross-sectional view showing a cross-section of the pipe and electrode shown in Figure 2.

[0038] FIG. 4 is a drawing for explaining an aperture portion as an example of a variable inlet of the foreign substance device illustrated in FIG. 1.

[0039] Fig. 5 is an exploded view of the aperture portion shown in Fig. 4.

[0040] FIG. 6 is a drawing for explaining the head portion as another example of the variable inlet of the foreign substance device illustrated in FIG. 1.

[0041] Figure 7 is a schematic diagram of a foreign substance detection device according to another embodiment of the present invention.

[0042] Fig. 8 is a drawing for explaining the process of detecting a foreign substance by the foreign substance detection device illustrated in Fig. 7.

[0043] FIG. 9 is a drawing for explaining a shielding part of a foreign substance detection device according to one embodiment of the present invention.

[0044] Hereinafter, various embodiments of the present invention will be described in detail with reference to the attached drawings so that those skilled in the art can easily implement the invention. The present invention may be implemented in various different forms and is not limited to the embodiments described herein.

[0045] In order to clearly explain the present invention, parts that are not related to the description are omitted, and the same reference numerals are used for identical or similar components throughout the specification.

[0046] Furthermore, the sizes and thicknesses of each component shown in the drawings are arbitrarily indicated for convenience of explanation, and thus the present invention is not necessarily limited to the illustrated components. In the drawings, the thicknesses are enlarged to clearly represent various layers and regions. Furthermore, in the drawings, the thicknesses of some layers and regions are exaggerated for convenience of explanation.

[0047] Furthermore, when we say that a layer, membrane, region, plate, or other part is "on" or "over" another part, this includes not only cases where it is "directly on" the other part, but also cases where there are other parts in between. Conversely, when we say that a part is "directly on" another part, it means that there are no other parts in between. Furthermore, saying that a part is "on" or "over" a reference part means that it is located above or below the reference part, and does not necessarily mean that it is located "above" or "over" the direction opposite to gravity.

[0048] Additionally, terms indicating directions such as front, back, left, right, up, and down are used, but these terms are only for convenience of explanation and may vary depending on the location of the target object or the location of the observer.

[0049] Additionally, throughout the specification, whenever a part is said to "include" a component, this does not mean that it excludes other components, but rather that it may include other components, unless otherwise specifically stated.

[0050] Additionally, throughout the specification, when we say "in plan", we mean when the target portion is viewed from above, and when we say "in cross section", we mean when the target portion is viewed from the side in a cross-section cut vertically.

[0051] Hereinafter, embodiments of the present invention will be described with reference to the drawings.

[0052] FIG. 1 is a schematic diagram of a foreign substance detection device according to one embodiment of the present invention. FIG. 2 is a drawing for explaining the process by which the foreign substance detection device illustrated in FIG. 1 detects foreign substances. FIG. 3 is a cross-sectional view illustrating the piping and electrode illustrated in FIG. 2.

[0053] Referring to FIGS. 1 to 3, a foreign substance detection device (100) according to one embodiment of the present invention may include an inlet (110) through which a fluid flows, a pipe (120) through which the fluid flowing in through the inlet (110) passes, an electrode (130) arranged to surround the pipe (120), a foreign substance detection sensor (140) that senses a change in electrostatic capacity caused by a foreign substance (p) in the fluid flowing through the pipe (120) through the electrode (130), and a processor (150) that detects the foreign substance (p) through an electrical signal of the foreign substance detection sensor (140).

[0054] The inlet (110) is a portion through which fluid flows into the foreign substance detection device (100). The inlet (110) is connected to a pipe (120), and thus, fluid flowing through the inlet (110) can flow into the pipe (120).

[0055] The cross-sectional area of ​​the inlet (110) may be different from the cross-sectional area of ​​the pipe (120). In particular, the inlet (110) may be a variable inlet whose cross-sectional area can be changed to vary the suction power depending on the size of the foreign substance. Meanwhile, the detailed configuration of the variable inlet described above will be described later.

[0056] The pipe (120) may be connected to an inlet (110) through which a fluid flows in and an outlet (180) through which the fluid flows out. In addition, the inlet (110) and the pipe (120) and the pipe (120) and the outlet (180) may be connected through separate pipes (not shown) through which the fluid may flow. Accordingly, the foreign substance detection device (100) according to one embodiment of the present invention can measure foreign substances (p) in the fluid around the foreign substance generation source (10) through a separate pipe connecting the inlet (110) and the pipe (120) even if it is placed at a long distance from the foreign substance generation source (10).

[0057] The electrode (130) may be arranged to surround the periphery of the pipe (120). The electrode (130) may be electrically connected to a power source supplied from a current source and / or a voltage source (not shown). When power is connected to the electrode (130), an electric field is formed by the electrode (130) surrounding the pipe (120), and thus, the electrostatic capacitance may be determined.

[0058] The foreign substance detection sensor (140) can detect a foreign substance (p) in a fluid passing through a pipe (120) via an electrode (130). For example, the foreign substance detection sensor (140) may be a capacitance sensor. Referring to FIG. 2, when a foreign substance (p) (e.g., a metal particle) contained in a fluid flowing into a pipe (120) passes through a pipe (120) in which an electrode (130) is arranged, the capacitance formed by the electrode (130) changes. The foreign substance detection sensor (140) can sense a change in the capacitance that occurs when the foreign substance (p) passes through. At this time, the foreign substance detection sensor (140) can generate an electrical signal corresponding to the change in the capacitance.

[0059] The processor (150) can detect a foreign substance (p) through an electrical signal generated from a foreign substance detection sensor (140). For example, the processor (150) can determine that a foreign substance (p) is included in the fluid flowing in the pipe (120) based on the electrostatic capacity corresponding to the electrical signal received from the foreign substance detection sensor (140) being greater than or equal to a predetermined value.

[0060] The processor (150) may include, for example, a microcontroller unit (MCU). The processor (150) may be provided within the foreign substance detection device (100) or separately provided outside the foreign substance detection device (100) to remotely communicate with the foreign substance detection device (100). The form of the processor (150) may be variously modified or changed depending on the environment in which the present invention is implemented.

[0061] As shown in FIGS. 2 and 3, the electrodes (130) may have anodes (130a) and cathodes (130b) arranged alternately along the periphery of the pipe (120), and more specifically, the electrodes (130) may have an interdigitated structure.

[0062] As the electrodes (130) are arranged alternately as anodes (130a) and cathodes (130b) along the circumference of the pipe (120), the electric field (dotted line illustrated in FIG. 3) formed by the electrodes (130) can be uniformly formed inside the pipe (120). Therefore, the foreign substance detection device (100) according to one embodiment of the present invention can accurately measure the change in electrostatic capacitance regardless of which part of the pipe (120) the foreign substance (p) passes through. However, the shape of the electric field illustrated by the dotted line in FIG. 3 is merely an example illustrated for the purpose of explaining the present invention, and may be variously modified and changed depending on the environment in which the present invention is implemented, such as the diameter of the pipe (120), the voltage applied to the electrodes (130), the width and spacing of the electrodes (130).

[0063] In addition, the foreign substance detection device (100) may include a pump (170) that sucks fluid into a pipe (120), a filter member (160) that filters the fluid that has passed through the electrode (130), and an outlet (180) through which the fluid that has passed through the filter member (160) is discharged to the outside.

[0064] A fluid containing a foreign substance (p) can be introduced into the pipe (120) through the inlet (110) by the suction force generated by the pump (170) and then discharged to the outside through the outlet (180). At this time, the foreign substance (p) contained in the fluid can be removed by the filter member (160) after passing through the pipe (120). Here, the removal of the foreign substance (p) may mean that the foreign substance (p) is separated from the fluid. The fluid from which the foreign substance (p) has been removed can be discharged to the outside of the foreign substance detection device (100) through the outlet (180).

[0065] At this time, the pump (170) may be located downstream of the filter member (160). Since the fluid from which foreign substances (p) have been removed by the filter member (160) can be introduced into the pump (170), the influence of the foreign substances on the pump (170) can be reduced.

[0066] Meanwhile, the pump (170) can suck the fluid into the pipe (120), and the filter member (160) can be of any conventional structure and method as long as it can remove foreign substances (p), so detailed descriptions of the pump (170) and the filter member (160) are omitted.

[0067] Fig. 4 is a drawing for explaining an aperture portion as an example of a variable inlet of the foreign substance device illustrated in Fig. 1. Fig. 5 is an exploded view of the aperture portion illustrated in Fig. 4.

[0068] Referring to FIGS. 4 and 5, the inlet (110) may include an aperture (110a) that is deformable between a first area and a second area.

[0069] The aperture portion (110a) may include a support plate (111a) with an open center, a plurality of blades (113a) rotatably coupled to the support plate (111a), a rotation plate (116a) with an open center that supports the plurality of blades (113a) together with the support plate (111a), and a guide portion that guides the rotation of the plurality of blades (113a).

[0070] The support plate (111a) has an open center for fluid introduction. A plurality of hinge protrusions (112a) may be formed on the support plate (111a) to rotatably connect a plurality of blades (113a). The plurality of blades (113a) are connected to the hinge protrusions (112a) and can rotate around the hinge protrusions (112a).

[0071] The plurality of blades (113a) are members for closing at least a portion of the open portion of the support plate (111a). A hinge hole (114a) into which a hinge protrusion (112a) is inserted may be formed at the distal end of the plurality of blades (113a). Accordingly, the hinge protrusion (112a) of the support plate (111a) is inserted into the hinge hole (114a) of the plurality of blades (113a), so that the plurality of blades (113a) can be rotatably coupled to the support plate (111a). However, the configuration of the hinge protrusion (112a) and the hinge hole (114a) described above is merely exemplary, and the coupling method by which the plurality of blades (113a) can be rotatably coupled to the support plate (111a) may be variously modified and changed depending on the environment in which the present invention is implemented.

[0072] Meanwhile, in FIGS. 4 and 5, the plurality of blades (113a) are illustrated as eight blades (113a) in which four blades (113a) are stacked in two stages, but the number and arrangement of the plurality of blades (113a) are not limited by the illustrated example. For example, a plurality of blades (113a) formed in one stage may be arranged, and the number of the plurality of blades (113a) may be variously modified and changed, such as three, four, five, or six, depending on the environment in which the present invention is implemented. In addition, the shape of the plurality of blades (113a) is not limited by the illustrated example, and may be variously modified and changed depending on the environment in which the present invention is implemented.

[0073] The area of ​​the inner diameter (118a) formed by the plurality of blades (113a) can be changed depending on the direction in which the plurality of blades (113a) rotate. For example, in the example illustrated in (a) of Fig. 4, the plurality of blades (113a) can rotate clockwise to the same position as the example illustrated in (b) of Fig. 4. In the example illustrated in (a) of Fig. 4, the plurality of blades (113a) completely close the support plate (111a), and in the example illustrated in (b) of Fig. 4, the plurality of blades (113a) form an inner diameter (118a) having a predetermined area. However, the direction in which the plurality of blades (113a) rotate is not limited to the illustrated example, and may be variously modified and changed depending on the environment in which the present invention is implemented.

[0074] The guide unit can guide the rotation of the plurality of blades (113a). The guide unit can include a guide groove (117a) formed in one of the plurality of blades (113a) and the rotation plate (116a) to guide the rotation of the plurality of blades (113a) and a guide protrusion (115a) formed in the other of the plurality of blades (113a) and the rotation plate (116a) and inserted into the guide groove (117a). For example, in the example illustrated in FIG. 5, a guide protrusion (115a) is formed in the plurality of blades (113a), a guide groove (117a) is formed in the rotation plate (116a), and the guide protrusion (115a) formed in the plurality of blades (113a) is inserted therein. Accordingly, the rotation of the plurality of blades (113a) can occur in accordance with the rotation of the rotation plate (116a).

[0075] For example, a user can adjust the rotation of the plurality of blades (113a) by rotating the rotation plate (116a), thereby adjusting the area of ​​the inner diameter (118a) formed by the plurality of blades (113a). However, the method of adjusting the rotation of the plurality of blades (113a) is not limited to what has been described above. For example, the foreign substance detection device (100) may further include an actuator (not shown) that causes the rotation of the plurality of blades (113a). The actuator may be driven under the control of the processor (150) and may be driven to reduce or increase the area of ​​the inner diameter (118a) formed by the plurality of blades (113a). Meanwhile, the above-described actuator and the control method of the actuator may be variously modified and changed depending on the environment in which the present invention is implemented, as long as the rotation of the plurality of blades (113a) can be achieved.

[0076] FIG. 6 is a drawing for explaining the head portion as another example of the variable inlet of the foreign substance device illustrated in FIG. 1.

[0077] Referring to FIG. 6, the variable inlet may include a head portion (110b, 110c) that is detachably coupled. The head portion (110b, 110c) may include a coupling portion (111b, 111c) that is coupled to the inlet (110) and an inlet portion (113b, 113c) through which fluid is introduced.

[0078] The cross-sectional area of ​​the inlet portions (113b, 113c) of the head portions (110b, 110c) may be different from the cross-sectional area of ​​the inlet port (110) from which the head portions (110b, 110c) are detached. Specifically, (a) of FIG. 6 shows an example in which the cross-sectional area of ​​the inlet portion (113b) of the head portion (110b) is larger than the cross-sectional area of ​​the inlet port (110). The head portion (110b) illustrated in (a) of FIG. 6 may include an enlarged portion (112b) whose cross-sectional area increases from the connecting end to the coupling portion (111b) toward the inlet portion (113b). (b) of FIG. 6 shows an example in which the cross-sectional area of ​​the inlet portion (113c) of the head portion (110c) is smaller than the cross-sectional area of ​​the inlet port (110). The head portion (110c) illustrated in (b) of Fig. 6 may include a connecting portion (111c) and a reducing portion (112c) whose cross-sectional area decreases as it moves from the connecting end toward the inlet portion (113c).

[0079] Accordingly, the foreign substance detection device (100) according to one embodiment of the present invention can increase the suction power according to the size of the foreign substance or suction a wider area of ​​fluid by increasing or decreasing the area of ​​the inlet (110) as needed. For example, the foreign substance detection device (100) according to one embodiment of the present invention can normally perform detection of foreign substances in a wider area by suctioning fluid through the inlet (110) having a large cross-sectional area. If the area where foreign substances are generated is expected or specified, the foreign substance detection device (100) can suction fluid through the inlet (110) having a small cross-sectional area to generate a stronger suction power, thereby suctioning relatively large foreign substances.

[0080] Fig. 7 is a schematic diagram of a foreign substance detection device according to another embodiment of the present invention. Fig. 8 is a diagram illustrating the process by which the foreign substance detection device illustrated in Fig. 7 detects foreign substances. In the following, descriptions of content identical or corresponding to those described with respect to the foreign substance detection device with reference to Figs. 1 to 3 will be omitted.

[0081] Referring to FIGS. 7 and 8, the electrode (130) may include a first electrode (131) and a second electrode (132) disposed downstream of the first electrode (131). The foreign substance detection sensor (140) may include a first foreign substance detection sensor (141) capable of sensing a change in electrostatic capacity caused by a foreign substance (p) in a fluid passing through the pipe (120) through the first electrode (131) and a second foreign substance detection sensor (142) capable of sensing a change in electrostatic capacity caused by a foreign substance (p) in a fluid passing through the pipe (120) through the second electrode (132). The processor (150) may detect a foreign substance (p) passing through the pipe (120) through the first foreign substance detection sensor (141) and the second foreign substance detection sensor (142).

[0082] At this time, the size of the foreign substance (p) measurable through the first foreign substance detection sensor (141) and the size of the foreign substance (p) measurable through the second foreign substance detection sensor (142) may be different from each other. For example, the second foreign substance detection sensor (142) can measure a foreign substance (p) having a smaller diameter than the first foreign substance detection sensor (141). In other words, the measurement sensitivity of the second foreign substance detection sensor (142) may be superior to the measurement sensitivity of the first foreign substance detection sensor (141). However, the relationship between the measurement sensitivities of the first foreign substance detection sensor (141) and the second foreign substance detection sensor (142) is not limited by the above-described description. For example, the first foreign substance detection sensor (141) may also measure a foreign substance (p) having a smaller diameter than the second foreign substance detection sensor (142).

[0083] In order to make the size of the foreign substance (p) measurable through the first foreign substance detection sensor (141) different from the size of the foreign substance (p) measurable through the second foreign substance detection sensor (142), at least one of the following conditions a) to d) may be satisfied.

[0084] a) The thickness (t1) of the first anode (131a) and the first cathode (131b) of the first electrode (131) may be different from the thickness (t2) of the second anode (132a) and the second cathode (132b) of the second electrode (132). For example, the thickness (t2) of the second anode (132a) and the second cathode (132b) of the second electrode (132) may be greater than the thickness (t1) of the first anode (131a) and the first cathode (131b) of the first electrode (131).

[0085] b) The gap (g1) between the first anode (131a) and the first cathode (131b) of the first electrode (131) may be different from the gap (g2) between the second anode (132a) and the second cathode (132b) of the second electrode (132). For example, the gap (g2) between the second anode (132a) and the second cathode (132b) of the second electrode (132) may be smaller than the gap (g1) between the first anode (131a) and the first cathode (131b) of the first electrode (131).

[0086] c) The first voltage applied to the first electrode (131) and the second voltage applied to the second electrode (132) may be different from each other. For example, the second voltage applied to the second electrode (132) may be greater than the first voltage applied to the first electrode (131).

[0087] d) As illustrated in FIG. 8, the first area of ​​the pipe (121) in which the first electrode (131) is disposed and the second area of ​​the pipe (122) in which the second electrode (132) is disposed may be different from each other. That is, the first diameter (D1) of the pipe (121) in which the first electrode (131) is disposed may be different from the second diameter (D2) of the pipe (122) in which the second electrode (132) is disposed. For example, the second diameter (D2) of the pipe (122) in which the second electrode (132) is disposed may be smaller than the first diameter (D1) of the pipe (121) in which the first electrode (131) is disposed.

[0088] The processor (150) can detect foreign substances (p) passing through the pipe (120) through electrical signals generated from the first foreign substance detection sensor (141) and the second foreign substance detection sensor (142). At this time, the processor (150) can calculate a ratio of the amount of foreign substances (p) detected through the first electrode (131) and the amount of foreign substances (p) detected through the second electrode (132).

[0089] For example, since the second foreign substance detection sensor (142) can measure foreign substances smaller in size than the first foreign substance detection sensor (141), the second foreign substance detection sensor (142) can measure both small and large foreign substances. On the other hand, the first foreign substance detection sensor (141) can measure only large foreign substances. That is, the ratio of small and large foreign substances can be calculated based on the amount of each foreign substance measured by the first foreign substance detection sensor (141) and the second foreign substance detection sensor (142).

[0090] In general, the larger the size of the foreign matter, the greater the physical damage (e.g., tearing of the separator) that may occur during the manufacturing process, which may increase the occurrence rate of low-voltage defects in lithium secondary batteries. Therefore, if a high proportion of large foreign matters is measured from a specific foreign matter generation source (10) through the foreign matter detection device (100) described above, flexible responses such as setting stronger countermeasures are possible.

[0091] FIG. 9 is a drawing for explaining a shielding part of a foreign substance detection device according to one embodiment of the present invention.

[0092] Referring to FIG. 9, the foreign substance detection device (100) may further include a shielding member (190) disposed outside the electrode (130). As illustrated in (a) of FIG. 9, the shielding member (190) may be in the form of a covering that surrounds the outside of the electrode (130). In addition, as illustrated in (b) of FIG. 9, the shielding member (190) may be in the form of a covering that is disposed between the electrode (130) and the noise source (20). However, the shape of the shielding member (190) is not limited to what has been described above, and may be variously modified or changed depending on the environment in which the present invention is implemented, as long as it has a form that can shield between the noise source (20) and the electrode (130). The noise source (20) may be, for example, a configuration that can affect the electrostatic capacitance of the electrode (130), such as a motor.

[0093] The material of the shielding portion (190) may be a polymer material such as PDMS (Polydimethylsiloxane), polyimide, etc. Alternatively, the material of the shielding portion (190) may be metal. In this case, the shielding portion (190) may be electrically connected to an external ground.

[0094] By placing the shielding member (190) outside the electrode (130), noise entering the electrode (130) from an external noise source (20) can be shielded. Accordingly, the measurement precision of the foreign substance detection sensor (140) can be improved, so that the foreign substance detection device (100) can detect foreign substances (p) contained in the fluid more precisely.

[0095] Meanwhile, in the above-described embodiments, the speed of the fluid flowing through the inlet (110) and through the pipe (120) can be implemented by being variously modified and changed depending on the process environment, the type of fluid, the amount of metal particles, etc. In some cases, the fluid can flow at a constant speed in the pipe (120), stop in the pipe (120), flow at an arbitrary speed in the pipe (120), or a combination of these can flow with a predetermined profile in the pipe (120).

[0096] In addition, the fluid flowing in the pipe (120) of the foreign substance detection device (100) according to the above-described embodiments may be air within the secondary battery manufacturing facility. For example, air within the secondary battery manufacturing facility may be introduced from outside the foreign substance detection device (100) through the above-described separate pipe. Through this, the foreign substance detection device (100) can monitor whether the air around the foreign substance generation source (10) located away from the location where the foreign substance detection device (100) is placed contains foreign substances, for example, metal particles.

[0097] If metal particles are included in the electrode during the electrode manufacturing process, they may grow during the operation of the lithium secondary battery, causing a leakage current between the positive and negative electrodes and causing low-voltage defects in the lithium secondary battery. Therefore, monitoring foreign substances, such as metal particles, is important during the electrode manufacturing process. The foreign substance detection device (100) according to the above-described embodiments can detect whether foreign substances are generated from a foreign substance generation source during the electrode manufacturing process. In particular, the foreign substance detection device (100) illustrated in FIGS. 7 and 8 can measure the ratio of large particles to small particles according to the size of the foreign particles. In general, the larger the size of the foreign substance, the greater the physical damage (e.g., tearing of the separator, etc.) that may occur during the manufacturing process, which may increase the occurrence rate of low-voltage defects in the lithium secondary battery. Therefore, if a high ratio of large particles is measured from a specific foreign substance generation source (10) through the foreign substance detection device (100), flexible responses such as setting stronger countermeasures are possible.

[0098] Meanwhile, the process in which the foreign substance detection device (100) according to the embodiments of the present invention can be used is not limited by what has been described above, and can be used in all processes that require monitoring the generation of foreign substances, for example, metal particles, generated by manufacturing equipment within a battery production line.

[0099] Although the preferred embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements made by those skilled in the art using the basic concept of the present invention defined in the following claims also fall within the scope of the present invention.

[0100] [Explanation of symbols]

[0101] 10: Source of foreign matter

[0102] 20: Noise source

[0103] 100: Foreign substance detection device

[0104] 110: Inlet

[0105] 110a: Aperture section

[0106] 111a: Support plate

[0107] 112a: Hinge protrusion

[0108] 113a: Blades of Vengeance

[0109] 114a: Hinge hole

[0110] 115a: Guide protrusion

[0111] 116a: Rotating plate

[0112] 117a: Guide Home

[0113] 110b, 110c: Head

[0114] 111b, 111c: Joints

[0115] 112b: Enlarged section

[0116] 112c: Reduced section

[0117] 113b, 113c: Inlet

[0118] 120: Piping

[0119] 130: Electrode

[0120] 130a: positive pole

[0121] 130b: cathode

[0122] 140: Foreign substance detection sensor

[0123] 150: Processor

[0124] 160: Filter absence

[0125] 170: Pump

[0126] 180: exhaust port

[0127] 190: Shielding

Claims

1. A pipe through which a fluid passes; Electrodes arranged to surround the periphery of the above pipe; and Includes a foreign substance detection sensor that senses a change in electrostatic capacity caused by foreign substances in the fluid passing through the pipe through the electrode, The above electrode is a foreign substance detection device in which positive and negative electrodes are alternately arranged along the circumference of the pipe.

2. In paragraph 1, A foreign substance detection device, wherein the above electrode has an interdigitated structure.

3. In paragraph 1, Further comprising an inlet port through which the fluid flows in, A foreign substance detection device in which the fluid introduced through the inlet flows into the pipe.

4. In paragraph 3, A foreign substance detection device wherein the above inlet is a variable inlet in which the cross-sectional area through which the fluid flows in can be changed.

5. In paragraph 4, A foreign matter detection device, wherein the variable inlet includes an aperture whose cross-sectional area is variable between a first area and a second area.

6. In paragraph 5, The above aperture part, Support plate with open center; A plurality of blades rotatably connected to the support plate; A rotating plate having an open center and supporting the plurality of blades together with the support plate; and A foreign substance detection device including a guide part that guides the rotation of the plurality of blades.

7. In paragraph 6, The above guide part, A guide groove formed in one of the blades and the rotating plate to guide the rotation of the plurality of blades; and A foreign substance detection device comprising a guide protrusion formed on the other of the blade and the rotating plate and inserted into the guide groove.

8. In paragraph 4, The variable inlet includes a head portion that is detachably coupled to the inlet, A foreign substance detection device, wherein the head portion includes a coupling portion coupled to the inlet port and an inlet port into which the fluid flows and has a cross-sectional area different from that of the inlet port.

9. In paragraph 8, A foreign substance detection device, wherein the head portion further includes an enlarged portion whose cross-sectional area increases as it moves from the coupling portion toward the inlet portion, or a reduced portion whose cross-sectional area decreases as it moves from the coupling portion toward the inlet portion.

10. In paragraph 1, The electrodes include a first electrode and a second electrode disposed downstream of the first electrode, A foreign substance detection device, wherein the foreign substance detection sensor comprises a first foreign substance detection sensor that measures a change in electrostatic capacity caused by the foreign substance in the fluid passing through the pipe through the first electrode, and a second foreign substance detection sensor that measures a change in electrostatic capacity caused by the foreign substance in the fluid passing through the pipe through the second electrode.

11. In paragraph 10, A foreign substance detection device, wherein the size of a foreign substance measurable through the first foreign substance detection sensor and the size of a foreign substance measurable through the second foreign substance detection sensor are different from each other.

12. In paragraph 11, A foreign substance detection device, wherein the thickness of the first anode and the first cathode of the first electrode are different from the thickness of the second anode and the second cathode of the second electrode.

13. In paragraph 11, A foreign substance detection device, wherein the distance between the first anode and the first cathode of the first electrode is different from the distance between the second anode and the second cathode of the second electrode.

14. In paragraph 11, A foreign substance detection device, wherein the first voltage applied to the first electrode and the second voltage applied to the second electrode are different from each other.

15. In paragraph 11, A foreign substance detection device, wherein the first area of ​​the pipe where the first electrode is placed and the second area of ​​the pipe where the second electrode is placed are different from each other.

16. In paragraph 11, Further comprising a processor that detects the foreign substance passing through the pipe through an electrical signal generated from the first foreign substance detection sensor and the second foreign substance detection sensor, A foreign substance detection device, wherein the processor calculates a ratio of the amount of foreign substances detected through the first electrode and the amount of foreign substances detected through the second electrode.

17. In paragraph 1, a pump for sucking the fluid into the pipe; and Further comprising a filter member for filtering the fluid passing through the electrode, The above pump is a foreign matter detection device located downstream of the above filter member.

18. In paragraph 1, A foreign substance detection device further comprising a shielding member disposed outside the electrode.

19. In paragraph 18, The above shielding member is formed of metal, The above shield is a foreign substance detection device electrically connected to an external ground.

20. In paragraph 1, The above fluid is a foreign substance detection device that is air inside a secondary battery manufacturing facility.

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