Flat magnetic flux sensor

Abstract

The utility model discloses a flat magnetic flux sensor, which belongs to the technical field of magnetic flux sensors, and solves the technical problem that the traditional circular magnetic flux sensor cannot be applied to a flat prestressed tendon using place with a limited space structure, the flat magnetic flux sensor comprises a spool with a flat structure, and the middle part of the spool is provided with a winding groove; a secondary coil is arranged in the winding groove, a primary coil wrapping the secondary coil is arranged on the outer wall of the bobbin, an outer sleeve wrapping the primary coil is arranged on the periphery of the bobbin, the outer sleeve is of a flat structure, and a thermistor is arranged in the outer sleeve. And a signal line of the secondary coil, a signal line of the primary coil and a signal line of the thermistor are electrically connected with a cable respectively to form a data line cable. The outer wall of the bobbin is provided with a wire outlet groove used for leading out a signal wire of the secondary coil. The magnetic flux sensor provided by the utility model is integrally flat, can be conveniently installed in a flat prestressed tendon using place with a limited space structure, and can ensure the measurement precision.

Description

Technical Field

[0001] The utility model relates to the technical field of magnetic flux sensors, and more specifically, to a flat magnetic flux sensor. Background Art

[0002] Prestressed flat anchors are used for post-tensioned simply supported T-beams, hollow slabs, low box girders with limited height in cities and other thin-walled structures, as well as transverse prestressing of bridge decks, etc., which can effectively reduce the height of beams or slabs. The current problem is that the post-tensioned prestressed concrete slabs are relatively thin, and the prestress loss of steel strands is large. At present, the force sensor can only measure the tension prestress, and cannot obtain the effective prestress of the prestressed strands in the concrete.

[0003] At present, the detection methods / detection products for internal prestress are limited to the detection of conventional internal prestress. For example, although the patent CN201811322693.0 "A detection structure and stress detection method for internal prestressed bundles" uses the magnetic flux method, it has not formed an integrated magnetic flux sensor. The patent CN113176017B "Steel strand internal prestress distribution monitoring method, monitoring system and use method thereof" pre-buries a magnetic resonance sensor with a primary coil and a secondary coil at the steel strand to be prestressed, and uses the change in the induced electromotive force of the secondary coil in the magnetic resonance sensor caused by the change in the prestress of the steel strand to monitor the prestress of the steel strand to monitor the prestress of the steel strand. The force measuring device of the above method is composed of multiple components or adopts a traditional sensor, which has high requirements on the space and volume of the use site and is only suitable for the detection of conventional internal prestress.

[0004] Traditional circular magnetic flux sensors cannot be embedded in places where flat prestressed tendons are used due to their shape and size limitations. When measuring the tension of flat prestressed tendons, the vertical distance between the cylindrical sensor and the component is too large, resulting in a decrease in measurement accuracy, which cannot meet the high-precision requirements of monitoring sensors during operation. Utility Model Content

[0005] The technical problem to be solved by the utility model is aimed at the above-mentioned deficiencies in the prior art. The purpose of the utility model is to provide a flat magnetic flux sensor.

[0006] The technical solution of the utility model is: a flat magnetic flux sensor, including a bobbin with a flat structure, a winding groove is provided in the middle of the bobbin, a secondary coil is provided in the winding groove, a primary coil is provided on the outer wall of the bobbin for covering the secondary coil, an outer sleeve is provided on the periphery of the bobbin for covering the primary coil, the outer sleeve is a flat structure, a thermistor is provided in the outer sleeve, and a signal line of the secondary coil, a signal line of the primary coil, and a signal line of the thermistor are respectively electrically connected to a cable line to form a data line cable.

[0007] As a further improvement, the outer wall of the bobbin is provided with a wire outlet groove for leading out the signal wire of the secondary coil.

[0008] Furthermore, an open ring is provided between the secondary coil and the primary coil to separate the two.

[0009] Furthermore, fixing plates are respectively provided on the peripheries of the bobbins at both ends of the primary coil, and a lining plate is provided between the fixing plates and the primary coil.

[0010] Furthermore, the fixing plate is a two-half structure, both ends of the fixing plate are respectively locked by bolts, and the lining plate is provided with a wire outlet for passing the signal wire of the secondary coil and the signal wire of the primary coil.

[0011] Furthermore, the outer wall of the spool is provided with a first mounting step for mounting the fixing plate.

[0012] Furthermore, a front baffle and a wire outlet baffle are respectively provided at both ends of the spool, the wire outlet baffle is provided with a wire outlet hole, and the two ends of the outer sleeve are respectively connected to the front baffle and the wire outlet baffle by bolts.

[0013] Furthermore, second installation steps for installing the front baffle and the wire outlet baffle are respectively provided at both ends of the bobbin.

[0014] Furthermore, the signal wire of the secondary coil, the signal wire of the primary coil, and the signal wire of the thermistor are covered with an insulating sleeve.

[0015] Furthermore, the data cable is connected to the outlet baffle via an anti-bending connector.

[0016] Beneficial Effects

[0017] Compared with the prior art, the utility model has the following advantages:

[0018] The magnetic flux sensor of the utility model is flat as a whole, and the dimensions of the long end and the short end can be set according to actual needs. It can be conveniently embedded in bridge components with higher size requirements, such as box girder wing plates, top plates, etc., which require a larger eccentricity, and can be installed in any section of the flat anchor prestressed tendons. The lateral and vertical spacings between the magnetic flux sensor and the component are consistent, which can ensure measurement accuracy and can effectively perform measurements during its tensioning construction period and operation period. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a schematic diagram of the main structure of the utility model;

[0020] Figure 2 It is a left-side structural schematic diagram of the utility model;

[0021] Figure 3 for Figure 1 The enlarged view of point A in the middle;

[0022] Figure 4 This is a schematic diagram of the structure of the middle and outer sleeves of the utility model;

[0023] Figure 5 It is a structural schematic diagram of the centerline shaft of the utility model;

[0024] Figure 6 It is a structural schematic diagram of the lining plate of the utility model.

[0025] Wherein: 1- bobbin, 2- winding groove, 3- secondary coil, 4- primary coil, 5- outer sleeve, 6- outlet groove, 7- open ring, 8- fixing plate, 9- lining plate, 10- first installation step, 11- front baffle, 12- outlet baffle, 13- second installation step, 14- anti-bending joint, 15- data cable, 16- first bolt, 17- second bolt, 18- semicircular arc plate, 19- connecting plate, 20- installation groove, 21- thermistor. DETAILED DESCRIPTION

[0026] The present invention will be further described below with reference to the specific embodiments in the accompanying drawings.

[0027] See also Figure 1 to Figure 6 A flat magnetic flux sensor comprises a bobbin 1 of a flat structure. A winding groove 2 is provided in the middle of the bobbin 1, and a secondary coil 3 is provided in the winding groove 2. The secondary coil 3 is wound by enameled wire and is neatly wound in the winding groove 2 according to a set number of turns, layers and winding force. A primary coil 4 covering the secondary coil 3 is provided on the outer wall of the bobbin 1. The primary coil 4 is wound by enameled wire and is neatly wound on the bobbin 1 according to a set number of turns, layers and winding force. An outer sleeve 5 covering the primary coil 4 is provided on the periphery of the bobbin 1. The outer sleeve 5 is of a flat structure, such as Figure 4 As shown, the outer sleeve 5 includes two semicircular arc plates 18, and the two semicircular arc plates 18 are connected by two connecting plates 19 to form a flat structure. The flat structure of the bobbin 1 is similar to the flat structure of the outer sleeve 5. Preferably, the bobbin 1 is made of PA1010 material or stainless steel material. The outer sleeve 5 is hot-dip galvanized, and the outer sleeve 5 is cut into two halves along the center line of a circular steel cylinder, and two connecting plates 19 are added to become a flat structure.

[0028] The outer sleeve 5 is provided with a thermistor 21, and the signal line of the secondary coil 3, the signal line of the primary coil 4, and the signal line of the thermistor 21 are respectively electrically connected with the cable line to form a data line cable 15. Specifically, the signal line of the secondary coil 3, the signal line of the primary coil 4, and the signal line of the thermistor 21 are respectively welded with a 6-core cable line or connected through a terminal to form a sensor data line cable 15. The presence of the thermistor 21 provides temperature compensation for the sensor measurement result.

[0029] The signal line of the secondary coil 3, the signal line of the primary coil 4, and the signal line of the thermistor 21 are covered with an insulating sleeve. Specifically, the connection between the signal line of the secondary coil 3, the signal line of the primary coil 4, the signal line of the thermistor 21 and the cable line is wrapped with an insulating sleeve (or a heat shrink tube), and then the signal line of the secondary coil 3, the signal line of the primary coil 4, and the signal line of the thermistor 21 are wrapped together with the insulating sleeve. The data line cable 15 is connected to the outlet baffle 12 through the anti-bending connector 14. The data line cable 15 is led out of the sensor through the anti-bending connector 14 fixed on the outlet baffle 12. The anti-bending connector 14 can effectively extend the service life of the sensor data line and achieve a good waterproof effect.

[0030] The outer wall of the bobbin 1 is provided with a wire outlet slot 6 for leading out the signal wire of the secondary coil 3 .

[0031] An open ring 7 is provided between the secondary coil 3 and the primary coil 4 to separate the two. The open ring 7 is made of PA1010 material, and the bobbin 1 is provided with a mounting groove 20 for mounting the open ring 7 .

[0032] Fixed plates 8 are respectively provided on the periphery of the bobbin 1 at both ends of the primary coil 4 , and a lining plate 9 is provided between the fixed plate 8 and the primary coil 4 , and the lining plate 9 is made of PA1010 material.

[0033] The fixing plate 8 is a two-half structure, and both ends of the fixing plate 8 are respectively locked by the first bolts 16, that is, the fixing plate 8 includes two symmetrical half fixing plates, and the two half fixing plates are locked by the first bolts 16. The lining plate 9 is provided with outlets for passing the signal wires of the secondary coil 3 and the signal wires of the primary coil 4, and the signal wires of the secondary coil 3 and the signal wires of the primary coil 4 pass through the gaps of the fixing plate 8.

[0034] The outer wall of the bobbin 1 is provided with a first mounting step 10 for mounting the fixing plate 8. The two ends of the bobbin 1 are respectively provided with a front baffle 11 and a wire outlet baffle 12, which are hot-dip galvanized, and the wire outlet baffle 12 is provided with a wire outlet hole, and the anti-bending joint 14 is installed in the wire outlet hole, that is, the data cable 15 passes through the anti-bending joint 14 and is electrically connected with the signal line of the secondary coil 3, the signal line of the primary coil 4, and the signal line of the thermistor 21. The two ends of the outer sleeve 5 are respectively connected to the front baffle 11 and the wire outlet baffle 12 by the second bolt 17. The two ends of the bobbin 1 are respectively provided with a second mounting step 13 for mounting the front baffle 11 and the wire outlet baffle 12.

[0035] The above are only preferred implementations of the utility model. It should be pointed out that for those skilled in the art, several modifications and improvements can be made without departing from the structure of the utility model, which will not affect the effect of the implementation of the utility model and the practicality of the patent.

Claims

1. A flat magnetic flux sensor, characterized in that: The invention comprises a flat-structured bobbin (1), a winding groove (2) is provided in the middle of the bobbin (1), a secondary coil (3) is provided in the winding groove (2), a primary coil (4) covering the secondary coil (3) is provided on the outer wall of the bobbin (1), an outer sleeve (5) covering the primary coil (4) is provided on the periphery of the bobbin (1), the outer sleeve (5) is a flat-structured bobbin, a thermistor (21) is provided in the outer sleeve (5), and a signal line of the secondary coil (3), a signal line of the primary coil (4), and a signal line of the thermistor (21) are respectively electrically connected to a cable line to form a data cable (15).

2. A flat magnetic flux sensor according to claim 1, characterized in that: The outer wall of the bobbin (1) is provided with a wire outlet groove (6) for leading out the signal wire of the secondary coil (3).

3. A flat magnetic flux sensor according to claim 1, characterized in that: An open ring (7) is provided between the secondary coil (3) and the primary coil (4) to separate the two.

4. A flat magnetic flux sensor according to claim 1, characterized in that: The outer peripheries of the bobbins (1) at both ends of the primary coil (4) are respectively provided with fixing plates (8), and a lining plate (9) is provided between the fixing plates (8) and the primary coil (4).

5. A flat magnetic flux sensor according to claim 4, characterized in that: The fixing plate (8) is a two-half structure, and the two ends of the fixing plate (8) are respectively locked by first bolts (16). The lining plate (9) is provided with an outlet for passing the signal line of the secondary coil (3) and the signal line of the primary coil (4).

6. A flat magnetic flux sensor according to claim 4, characterized in that: The outer wall of the bobbin (1) is provided with a first mounting step (10) for mounting the fixing plate (8).

7. A flat magnetic flux sensor according to claim 1, characterized in that: The two ends of the spool (1) are respectively provided with a front baffle (11) and a wire outlet baffle (12), the wire outlet baffle (12) is provided with a wire outlet hole, and the two ends of the outer sleeve (5) are respectively connected to the front baffle (11) and the wire outlet baffle (12) by second bolts (17).

8. A flat magnetic flux sensor according to claim 7, characterized in that: Second installation steps (13) for installing the front baffle (11) and the outlet baffle (12) are respectively provided at both ends of the bobbin (1).

9. The flat magnetic flux sensor according to claim 1, characterized in that: The signal line of the secondary coil (3), the signal line of the primary coil (4), and the signal line of the thermistor (21) are covered with insulating sleeves at their peripheries.

10. The flat magnetic flux sensor according to claim 7, characterized in that: The data line cable (15) is connected to the line outlet baffle (12) via an anti-bending connector (14).

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