JP6840491B2 - Clamp sensor and measuring device - Google Patents

Description

The present invention includes a clamp sensor that detects a detected amount of a clamped object in a state where the clamped object is clamped by a pair of sensors having a substantially arc shape in a plan view, and measures the measured amount of the clamped object by providing the clamp sensor. It is related to the measuring device to be used.

As a clamp sensor of this type, a clamp sensor disclosed by the applicant in Patent Document 1 below is known. This clamp sensor is configured to include a movable side sensor and a fixed side sensor formed in a substantially arc shape in a plan view, respectively. In this case, the movable side sensor is rotatably connected around the base end portion by inserting the connecting pin through the base end portion. When detecting the current flowing through the electric wire by using this clamp sensor, for example, the lever provided at the base end portion of the movable side sensor is gripped. At this time, the movable side sensor rotates, and the tips of the sensors separate from each other. Next, the electric wire is passed through the separated portion, and then the gripped state with respect to the lever is released. At this time, the urging force of the spring causes the tips of the sensors to come into contact with each other, and the annular body composed of the sensors surrounds and clamps the electric wire. Then, each sensor detects the current flowing through the electric wire.

Japanese Unexamined Patent Publication No. 2007-17188 (Pages 4-5, Fig. 1)

However, the above-mentioned clamp sensor has the following problems to be improved. That is, in this type of clamp sensor including the above-mentioned clamp sensor, the thickness of each sensor is set to a predetermined thickness or more (relative to the thickness of the electric wire to be detected) in order to secure sufficient sensitivity. It needs to be thick enough). Further, the clamp sensor is formed in a shape (a shape having a substantially square cross section) in which the ratio of the depth (thickness) and the width of each sensor is approximately 1. Therefore, when another electric wire is wired in the vicinity of the electric wire to be detected or an obstacle exists in the vicinity of the electric wire to be detected, the clamp sensor clamps the electric wire to be detected. This can be difficult, and improvements in this regard are desired.

The present invention has been made in view of the problem to be improved, and an object of the present invention is to provide a clamp sensor and a measuring device capable of reliably clamping an object to be clamped.

In order to achieve the above object, the clamp sensor according to claim 1 is formed in a substantially arc shape in a plan view, and at least one of the clamp sensors can be rotated around a rotation axis on the base end side so that the tips can be opened and closed. A clamp sensor having a pair of sensor units configured in the above, and configured to be able to detect the detected amount of the clamped object in a state where the clamped object is clamped by each of the sensor units. The sensor case and the core housed in the sensor case are each provided, and the magnetic detection element that detects the magnetism generated in the core as the detected amount in the state where the clamped object is clamped is one of the sensor units. housed in one of the sensor case, the sensor case, at least each of said tip side, wherein the first length of the perpendicular to the length direction of the sensor sections and a direction perpendicular to the pivot axis It is formed in a thin shape in which the ratio to the second length in the direction along the rotation axis is in the range of 0.1 or more and 0.6 or less, and each of the tips is closed. The inner circumference of the portion on the base end side of the annular body formed by the sensor portion is formed so as to form a semicircular shape in a plan view , and the portion on the tip end side of the portion is formed in the thin shape. It is, and ratio of the second length of the first length at the site of the tip side is defined in the same value in the longitudinal direction, wherein each core, perpendicular vital the lengthwise The ratio of the third length in the direction orthogonal to the rotation axis to the fourth length in the direction along the rotation axis is about the same as the ratio of the first length to the second length. And the cross-sectional area is formed in a substantially constant shape in the length direction .

Further, the clamp sensor according to claim 2 is the clamp sensor according to claim 1. In the sensor case , the curvature of the portion on the tip end side in a plan view is larger than the curvature of the portion on the proximal end side in a plan view. Is also formed to be small.

Further, the clamp sensor according to claim 3 is the clamp sensor according to claim 2, wherein the portion of the sensor case on the tip end side has a linear shape.

The measuring device according to claim 4 relates to the clamp sensor according to any one of claims 1 to 3 and the clamp target based on the magnetic detection amount as the detected amount detected by the clamp sensor. It is equipped with a measuring unit that measures the amount to be measured.

According to the clamp sensor according to claim 1 and the measuring device according to claim 4, the length ( first length: width) in the direction orthogonal to the length direction of each sensor unit and orthogonal to the rotation axis. At least each of the sensor cases in each sensor unit has a thin shape in which the ratio to the length (second length: depth) in the direction along the rotation axis of is within the range of 0.1 or more and 0.6 or less. By forming the tip side, even when an obstacle exists in the vicinity of the clamp target, the clamp target and the obstacle are compared with the conventional configuration in which the ratio of the width and the depth is defined to be approximately 1. The sensor unit can be reliably and easily inserted into the narrow gap between the object and the object. Therefore, according to this clamp sensor and the measuring device, the clamp target can be reliably clamped even when an obstacle exists in the vicinity of the clamp target.

Further, according to this clamp sensor and this measuring device, the inner circumference of the portion on the base end side of the annular body formed by each sensor portion in a state where the tip portions are closed forms a semicircle in a plan view. Compared with the configuration in which the sensor case is formed as described above and the portion on the tip side of the portion is formed in a thin shape, so that the portion on the tip side and the portion on the proximal end side are all formed in a thin shape. Therefore, the strength of each sensor unit can be sufficiently increased.

Further, according to the clamp sensor according to claim 2 and the measuring device according to claim 4, the curvature of the portion on the tip end side in the plan view is smaller than the curvature of the portion on the proximal end side in the plan view. By forming the sensor case of each sensor part, the thin tip side part has a linear shape, and as a result, the tip side part and the base end side part are formed to have the same curvature. Unlike the configuration in which each sensor unit has an arc shape in a plan view as a whole, when an obstacle exists in the vicinity of the clamp target, the tip portion of the sensor unit is in a narrow gap between the clamp target and the obstacle. The tip can be securely and easily inserted into the gap simply by pushing straight in.

It is a perspective view of the clamp meter 1. It is a block diagram which shows the structure of the clamp meter 1. It is a perspective view of the clamp meter 1 when the sensor part 11a, 11b is in an open state. It is a front view of the clamp meter 1. It is a side view of the clamp meter 1. It is explanatory drawing explaining the use method of the clamp meter 1.

Hereinafter, embodiments of the clamp sensor and the measuring device will be described with reference to the accompanying drawings.

First, the configuration of the clamp meter 1 will be described. The clamp meter 1 shown in FIGS. 1 and 2 is an example of a measuring device, for example, measuring a current (an example of a measured quantity) flowing through an electric wire 200a as a clamp target shown in FIG. 4 in a non-contact manner (non-contact with metal). It is configured to be possible. Specifically, the clamp meter 1 includes a clamp sensor 2 and a main body 3.

As shown in FIGS. 1 and 3, the clamp sensor 2 includes a pair of sensor units 11a and 11b, and as shown in FIG. 4, the electric wire 200a is clamped (surrounded) by the sensor units 11a and 11b. The magnetic field as the amount to be detected generated when a current is flowing through 200a is detected in a non-contact manner.

Further, in this sensor 2, as shown in FIGS. 4 and 6, the sensor unit 11b (one of the sensor units 11a and 11b) opens and closes (contacts and detaches) the tip portions 21a and 21b of the sensor units 11a and 11b. The sensor unit 11a is fixed to the main body case 30 of the main body 3 in a non-rotating state so as to be rotatable around the rotation shaft 23. Further, in this sensor 2, the sensor unit 11b is configured to rotate in response to an operation (pushing in and releasing) of the lever 30a arranged in the main body case 30. In the following description, the state in which the tips 21a and 21b of the sensor portions 11a and 11b are closed (the state shown in FIG. 4) is also referred to as a "closed state", and the states in which the tips 21a and 21b are open (FIG. 4). The state shown in 6) is also referred to as an "open state".

Further, as shown in FIG. 4, the sensor unit 11a includes a sensor case 10a, a core (not shown) housed in the sensor case 10a, and a magnetic detection element. Further, as shown in the figure, the sensor unit 11b includes a sensor case 10b and a core (not shown) housed in the sensor case 10b. In this case, the core is formed of a magnetic material, has a rectangular cross section, and has a substantially constant cross-sectional area in the length direction of the core. Further, the cross section of the core is the width (length in the direction orthogonal to the depth : the third length ) with respect to the depth (the length in the direction from the front side to the back side of the paper surface in FIG. 4: the fourth length). The ratio is defined to be about the same as the ratio R (the ratio of the width W to the depth D of the sensor units 11a and 11b) described later. Further, as an example, the magnetic detector element is composed of a Hall element, and in a state where the electric wire 200a is clamped by the sensor units 11a and 11b, a magnetic field as a detected amount generated in the core when a current is flowing through the electric wire 200a is generated. Detect and output the detection signal.

Further, as shown in FIGS. 1, 3 and 4, the sensor units 11a and 11b are formed in a substantially arc shape in a plan view shape (a shape viewed in a direction along the axis of the rotation shaft 23), respectively. Specifically, as shown in FIG. 4, the sensor portions 11a and 11b are on the base end portions 22a and 22b side of the annular body 100 formed by the sensor portions 11a and 11b when the tip portions 21a and 21b are closed to each other. The inner circumference of the part is formed so as to form a semicircular shape in a plan view. In the following description, each portion of the sensor portions 11a and 11b constituting this portion on the proximal end portions 22a and 22b is also referred to as "base end portion side portions 52a and 52b", respectively. Further, the portion of the sensor portion 11a on the tip portion 21a side (hereinafter, also referred to as “tip portion side portion 51a”) and the portion of the sensor portion 11b on the tip portion 21b side (hereinafter, also referred to as “tip portion side portion 51b”) are It is formed so that the curvature is smaller (the radius of curvature is larger) than the base end side portions 52a and 52b. That is, as shown in the figure, the sensor portions 11a and 11b are formed in a shape forming an elongated annular body 100 in the closed state.

Further, as shown in FIGS. 4 and 5, each of the tip end side portions 51a and 51b of the sensor portions 11a and 11b has a length in a direction along the axis of the rotation shaft 23 ( second length: hereinafter, this The length is also referred to as "depth D" (see FIG. 5), and is the length in the direction orthogonal to the length direction of the sensor units 11a and 11b and orthogonal to the rotation axis 23 ( first length: hereinafter, this). The length is also referred to as "width W" (see FIG. 4), and the ratio R is smaller than 1 (that is, the width W is shorter than the depth D). In this case, when the ratio R is larger than 0.6, the sensor portions 11a and 11b cannot be sufficiently thinned, so that the effect of the thinning is that "the electric wire 200a can be reliably clamped" (this effect). Will be described in detail later). On the other hand, when the ratio R is less than 0.1, the cores constituting the sensor units 11a and 11b become too thin, the magnetic characteristics deteriorate, and the detection accuracy of the magnetism (detected amount) of the clamp sensor 2 may decrease. There is. Therefore, in order to fully exert the effect of thinning while maintaining high accuracy of magnetic detection, it is necessary to specify the ratio R to a value within the range of 0.1 or more and 0.6 or less, and this clamp. In the sensor 2, the ratio R is defined as 0.5.

As shown in FIG. 2, the main body portion 3 includes a display unit 31, an operation unit 32, a processing unit 33, and a main body case 30 (see FIG. 1) in which each of these components is housed or arranged. ing.

The display unit 31 is composed of, for example, a liquid crystal panel, and is arranged on the front panel of the main body case 30 as shown in FIGS. 1, 3 and 4. Further, the display unit 31 displays the measured value of the current or the like according to the control of the processing unit 33. The operation unit 32 is configured to include various switches 32a, dials 32b, etc. arranged on the front panel of the main body case 30, and outputs operation signals corresponding to these operations.

The processing unit 33 controls each unit constituting the main body unit 3 according to an operation signal output from the operation unit 32. Further, the processing unit 33 functions as a measuring unit, measures the current value of the current flowing through the electric wire 200a based on the detection signal output from the clamp sensor 2 (magnetic detection element), and displays it on the display unit 31.

Next, a method of measuring the current value of the current flowing through the electric wire 200a to be clamped by using the clamp meter 1 will be described with reference to the drawings. In this case, as shown in FIG. 6, it is assumed that the electric wire 200b is wired in the vicinity of the electric wire 200a.

First, the lever 30a (see FIG. 6) of the main body 3 is pushed in. At this time, the sensor portion 11b rotates in the direction in which the tip portions 21a, 21b of the sensor portions 11a, 11b of the clamp sensor 2 are opened against each other against the urging force of the spring (not shown), as shown in FIG. In addition, the sensor units 11a and 11b are opened.

Next, as shown in FIG. 6, the sensor unit is located in the gap between the electric wires 200a and 200b arranged close to each other so that the electric wires 200a are located between the tip portions 21a and 21b of the sensor units 11a and 11b. The tip portion 21b of 11b is inserted.

In this case, in this clamp sensor 2, as described above, the width W of the tip side portions 51a and 51b is 0.5 with respect to the depth D (the width W is 1/2 of the depth D) and has a thin shape. The sensor portions 11a and 11b are formed. Therefore, in this clamp sensor 2, even when the wire 200b is wired in the vicinity of the wire 200a to be clamped, the ratio R of the width W and the depth D is defined as approximately 1 as compared with the conventional configuration. Therefore, the sensor unit 11b can be reliably and easily inserted into the narrow gap between the electric wires 200a and 200b. Further, in this clamp sensor 2, as described above, the sensor portions 11a and 11b are formed so that the tip end side portions 51a and 51b have a smaller curvature than the proximal end side portions 52a and 52b. As shown in 6, the thin tip portions 21a and 21b of the sensor portions 11a and 11b have a linear shape. Therefore, in the clamp sensor 2, the tip end side portions 51a and 51b and the proximal end side portions 52a and 52b are formed to have the same curvature, and the sensor portions 11a and 11b have an arc shape as a whole. Unlike this, the tip portion 21b of the sensor portion 11b can be reliably and easily inserted into the narrow gap between the electric wires 200a and 200b simply by pushing the clamp meter 1 straight.

Subsequently, the electric wire 200a is positioned between the base end portions 22a and 22b of the sensor portions 11a and 11b, and then the pushing against the lever 30a is released. At this time, the sensor portion 11b rotates in the direction in which the tip portions 21a, 21b of the sensor portions 11a, 11b come into contact with each other due to the urging force of the spring (not shown), and as shown in FIG. 4, the sensor portions 11a, 11b Is closed. As a result, as shown in the figure, the electric wire 200a is clamped by the sensor portions 11a and 11b (in the figure, the electric wire 200b is not shown). In this case, in this clamp sensor 2, as described above, the sensor portions 11a and 11b are formed in a thin shape, and the sensor portions 11b can be reliably and easily inserted into the narrow gap between the electric wires 200a and 200b. It is possible to securely clamp the electric wire 200a.

Subsequently, the magnetic detection element arranged in the sensor unit 11a detects the magnetic field generated in each core of the sensor units 11a and 11b by the current flowing through the electric wire 200a, and outputs a detection signal. Next, the processing unit 33 of the main body 3 measures the current value of the current flowing through the electric wire 200a based on the detection signal. Subsequently, the processing unit 33 causes the display unit 31 to display the measured value.

Next, when the measurement is completed, the lever 30a is pushed in to open the sensor units 11a and 11b, and then the clamp sensor 2 is pulled away from the electric wire 200a. Next, the push against the lever 30a is released to close the sensor units 11a and 11b.

As described above, according to the clamp sensor 2 and the clamp meter 1, the tip portions 21a and 21b sides of the sensor portions 11a and 11b are formed into a thin shape having a width W of 0.5 with respect to the depth D. Even when an obstacle such as another electric wire 200b exists in the vicinity of the electric wire 200a to be clamped, the electric wire is compared with the conventional configuration in which the ratio R of the width W and the depth D is approximately 1. The sensor unit 11b can be reliably and easily inserted into the narrow gap between the 200a and the obstacle. Therefore, according to the clamp sensor 2 and the clamp meter 1, the electric wire 200a can be reliably clamped even when an obstacle exists in the vicinity of the electric wire 200a to be clamped.

Further, according to the clamp sensor 2 and the clamp meter 1, the proximal end portion 52a on the proximal end portions 22a, 22b side of the annular body 100 formed by the sensor portions 11a, 11b in a state where the distal end portions are closed to each other. , 52b is formed so as to form a semicircular shape in a plan view, and the tip portion side portions 51a, 51b on the tip end portion 21a, 21b side of the proximal end portion side portions 52a, 52b are formed into a thin shape. The strength of the sensor portions 11a and 11b can be sufficiently increased as compared with a configuration in which all of the tip end side portions 51a and 51b and the proximal end side portions 52a and 52b are formed in a thin shape.

Further, according to the clamp sensor 2 and the clamp meter 1, the sensor portions 11a, so that the curvatures of the tip end side portions 51a and 51b in the plan view are smaller than the curvatures of the proximal end side portions 52a and 52b in the plan view. By forming 11b, the thin tip side portions 51a and 51b have a linear shape, and as a result, the tip side portions 51a and 51b and the proximal end side portions 52a and 52b are formed so as to have the same curvature. Unlike the configuration in which the sensor units 11a and 11b form an arc shape in a plan view as a whole, when an obstacle exists in the vicinity of the electric wire 200a, the sensor unit is formed in a narrow gap between the electric wire 200a and the obstacle. The tip portion 21b can be reliably and easily inserted into the gap simply by pushing the tip portion 21b of the 11b straight.

The configuration of the clamp sensor and the measuring device is not limited to the above configuration. For example, the example in which the sensor portions 11a and 11b are formed so that the width W is 0.5 with respect to the depth D has been described above, but the ratio of the width W to the depth D is in the range of 0.1 or more and 0.6 or less. It can be specified arbitrarily within.

Further, although the example in which the entire range of the tip portion side portions 51a and 51b is formed into a thin shape is described above, the range formed into the thin shape is the tip portion side portions 51a and 51b as long as the tip portions 21a and 21b sides are included. Only a part (a part on the tip 21a, 21b side of the boundary between the tip side portions 51a, 51b and the proximal end side portions 52a, 52b) may be used. Further, in addition to the tip end side portions 51a and 51b, a configuration in which all or part of the base end side portions 52a and 52b are formed into a thin shape can also be adopted. Further, the example in which the tip end side portions 51a and 51b are formed so that the curvature is smaller than that of the proximal end side portions 52a and 52b has been described above, but the curvature of the distal end side portions 51a and 51b is the proximal end side portion 52a. It is also possible to adopt a configuration in which the curvature is greater than or equal to the curvature of 52b.

Further, although the example in which the sensor unit 11b (one of the sensor units 11a and 11b) is configured to be rotatable has been described above, the sensor unit 11a can be configured to be rotatable and both the sensor units 11a and 11b can be rotated. It can also be configured as.

Further, the example in which the clamp sensor 2 detects the magnetic field as the detected amount and the processing unit 33 measures the current as the measured amount has been described above, but the detected amount and the measured amount are limited to the magnetic field and the current. It includes various physical quantities such as voltage, power and resistance.

1 Clamp meter 2 Clamp sensor 11a, 11b Sensor part 21a, 21b Tip part 22a, 22b Base end part 23 Rotating shaft 33 Processing part 51a, 51b Tip side part 52a, 52b Base end side part 100 Annulus 200a Electric wire D Depth R Ratio W Width

Claims (4)

Each sensor unit is provided with a pair of sensor units that are formed in a substantially arc shape in a plan view and at least one of them is rotatable around a rotation axis on the base end portion side so that the tip portions open and close. It is a clamp sensor configured to be able to detect the detected amount of the clamped object in the state where the clamped object is clamped by.
Each of the sensor units includes a sensor case and a core housed in the sensor case, and a magnetic detection element that detects the magnetism generated in the core in a state where the clamped object is clamped as the detected amount. It is housed in the sensor case of one of the sensor units.
The sensor case is at least each of said tip side, first the direction along the rotation axis of the first length of the perpendicular to the length direction of the sensor sections and a direction perpendicular to the pivot axis The said in an annular body formed in a thin shape in which the ratio to the length of 2 is in the range of 0.1 or more and 0.6 or less, and formed by each sensor portion in a state where the respective tip portions are closed. The inner circumference of the portion on the base end side is formed so as to form a semicircle in a plan view , the portion on the tip end side of the portion is formed in the thin shape, and the portion on the tip end side is formed. The ratio of the first length to the second length is defined as the same value in the length direction .
Each core has the first length as a ratio of a third length in a direction orthogonal to the length direction and orthogonal to the rotation axis to a fourth length in a direction along the rotation axis. A clamp sensor that is defined to be about the same as the ratio to the second length and has a substantially constant cross-sectional area in the length direction. The clamp sensor according to claim 1, wherein the sensor case is formed so that the curvature of the portion on the tip end side in a plan view is smaller than the curvature of the portion on the proximal end side in a plan view. The clamp sensor according to claim 2, wherein the portion of the sensor case on the tip end side has a linear shape. The clamp sensor according to any one of claims 1 to 3, and a measuring unit that measures a measured amount for the clamped object based on the magnetically detected amount as the detected amount detected by the clamp sensor. Equipped with measuring equipment.

Images