JP2009064711A - Proximity-sensor manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a proximity-sensor manufacturing method that manufactures an easily-manufacturable and high-reliability proximity sensor while preventing the occurrence of a variation in the outside dimension of a proximity sensor. <P>SOLUTION: The proximity-sensor manufacturing method is configured to prevent the occurrence of a variation in the total length of a proximity sensor by the following manner. First jigs 81, 85 are mounted to a terminal-part assembly 40 while a body-part assembly 70 is placed on a second jig 90. The first jigs and the second jig are used so as to adjust a proximity-sensor dimension by adjusting the size of a gap formed between the rear end of a processing circuit board 50 and a pin holder. The terminal-part assembly 40 is assembled and fixed to the processing circuit board 50. The terminal-part assembly 40 is positioned and fixed in such a manner. A holder member is abutted against and fixed to the terminal-part assembly 40 so as to prevent the occurrence of a variation in the total length of the proximity sensor. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a method of manufacturing a proximity sensor that uses a detection coil to detect the presence or position of a metal body as a detection object, and in particular, proximity that can prevent the occurrence of variations in the axial dimension of the proximity sensor. The present invention relates to a method for manufacturing a sensor.

  A proximity sensor is known as one of sensors that detect the presence or position of a metal body as a detection target. This proximity sensor is widely used mainly for various production facilities and industrial robots.

  Generally, a proximity sensor includes a case body and a holder member formed in a cylindrical shape, a coil assembly including a core and a detection coil, a terminal assembly including a terminal pin for external connection, a detection coil and a terminal pin. And a processing circuit board provided with an electrically connected processing circuit. The coil assembly is assembled and fixed inside the case body and at the front end of the case body, and the terminal assembly is assembled and fixed inside a holder member connected to the rear end of the case body. The processing circuit board provided with the processing circuit is arranged behind the coil assembly and in front of the terminal assembly so as to extend along the axial direction of the case body inside the case body.

  In the proximity sensor having such a configuration, conventionally, in order to prevent variation in the outer dimension of the proximity sensor in the axial direction, the terminal unit assembly is positioned and fixed to the holder member so as to be fixed, Positioning and fixing has been performed by holding the holder member against the case body. Then, in order to absorb the dimensional accuracy variation of internal components (coil assemblies, processing circuit boards, etc.) arranged side by side in the axial direction and the variation in assembly accuracy between these components, A gap was provided, and the above variation was absorbed by the gap. In addition, a lead wire, a flexible substrate, etc. were used for the electrical connection between these components.

  When manufacturing this type of proximity sensor, the coil assembly is assembled in advance by fixing it to the front end of the processing circuit board to form an intermediate assembly part, and the intermediate assembly part is inserted into the case body and fixed. After that, the terminal part assembly and the holder member are attached to the rear end of the case body, and the terminal pins and the rear end of the processing circuit board are electrically connected to assemble them. Thereafter, a liquid resin material is injected into the space inside the case body, and the internal components are sealed by curing the resin material.

References disclosing the proximity sensor configured as described above and the manufacturing method thereof include, for example, Japanese Patent Application Laid-Open No. 2004-111116 (Patent Document 1), Japanese Patent Application Laid-Open No. 2004-153018 (Patent Document 2), -98234 (patent document 3) and the like.
JP 2004-111116 A JP 2004-153018 A Japanese Utility Model Publication No. 4-98234

  However, the proximity sensor configured as described above has the following problems. First, because it is a configuration in which components arranged apart in the axial direction are connected by lead wires or a flexible substrate, the connection work between the lead wires or flexible substrate and the above components is not easy and is assembled. There was a problem that the work would be complicated. Secondly, there is a risk that the lead wire or flexible substrate may be assembled in contact with the inner wall surface of the case body. If such contact occurs, the water resistance and insulation resistance will deteriorate. There was a problem that. Thirdly, it is not easy to make the heat stress resistance strong at the solder joint between the lead wire or flexible substrate and the above-mentioned component, and there is a problem that the part deteriorates over time.

  As described above, when the configuration as described above is employed to prevent variation in the external dimension of the proximity sensor in the axial direction, the assembly work becomes complicated and the reliability is lowered. The result was a problem.

  Accordingly, the present invention has been made to solve the above-described problems, and can prevent the occurrence of variations in the outer dimensions of the proximity sensor, and can be easily manufactured and has high reliability. It is an object of the present invention to provide a method for manufacturing a proximity sensor.

The proximity sensor manufacturing method according to the first aspect of the present invention includes a cylindrical case body having a front end and a rear end in the axial direction, and a detection coil, and is provided inside the case body and at the front end of the case body. The coil assembly is electrically connected to the detection coil, and is disposed behind the coil assembly so as to extend along the axial direction of the case body inside the case body. A proximity sensor comprising: a processing circuit board; and a terminal assembly that includes at least a terminal pin for external connection, is electrically connected to the processing circuit board, and is disposed at a rear end of the processing circuit board. A manufacturing method comprising the following steps.
(A) The processing circuit board is assembled and fixed to the coil assembly, and the coil assembly on which the processing circuit board is assembled and fixed is assembled and fixed to the case body. Steps to prepare.
(B) In the first jig having the first reference position and the second reference position that are separated by a predetermined distance, the terminal portion is arranged so that the predetermined position of the terminal portion assembly matches the first reference position. Positioning and setting the assembly.
(C) The main body portion is arranged such that the predetermined position of the main body portion assembly matches the third reference position on a second jig having a third reference position and a fourth reference position that are separated by a predetermined distance. Positioning and setting the assembly.
(D) The first jig on which the terminal assembly is set and the second jig on which the main body assembly is set so that the second reference position and the fourth reference position coincide with each other. Positioning and setting.
(E) A step of fixing the terminal part assembly to the main body part assembly while maintaining the positioned state.
(F) A step of removing the first jig and the second jig from the main body part assembly and the terminal part assembly.

  In the proximity sensor manufacturing method according to the first aspect of the present invention, in the step of positioning and setting the terminal assembly on the first jig (step (B)), Preferably, the predetermined position of the terminal assembly to be matched with a reference position is the rear end of the terminal pin, and the main body assembly is positioned and set on the second jig. In the step (C), the predetermined position of the main body assembly to be matched with the third reference position is preferably the front end of the main body assembly.

  In the proximity sensor manufacturing method according to the first aspect of the present invention, the first jig has the first reference surface at the first reference position and the second reference surface at the second reference position. Preferably, the second jig has a third reference surface at the third reference position and a fourth reference surface at the fourth reference position. In this case, the step of positioning and setting the terminal assembly on the first jig (step (B)) is performed by abutting the rear end of the terminal pin against the first reference surface. Preferably, the step of positioning and setting the main body assembly on the second jig (step (C)) pushes the front end of the main assembly to the third reference plane. Is preferably done by applying Positioning and setting the first jig on which the terminal part assembly is set and the second jig on which the main body part assembly is set (step (D) above) It is preferable to carry out by abutting the second reference plane and the fourth reference plane.

  In the proximity sensor manufacturing method according to the first aspect of the present invention, in the state where the first jig is set to the terminal assembly, the first reference surface is placed behind the terminal pin. It is preferable to include a biasing member that biases in the direction of pressing against the end. In this case, the step of positioning and setting the terminal assembly on the first jig (step (B) above) However, it is preferable that the rear end of the terminal pin of the terminal assembly is brought into contact with the first reference plane by using a biasing force by the biasing member.

  In the proximity sensor manufacturing method according to the first aspect of the present invention, the first jig is attached to the terminal part assembly in a state where the terminal part assembly is set. It is preferable that the second jig is placed on the main body assembly in a state where the main body assembly is set.

A method for manufacturing a proximity sensor according to a second aspect of the present invention includes a cylindrical case body having a front end and a rear end in the axial direction and at least a detection coil, the interior of the case body, and the front end of the case body The coil assembly is electrically connected to the detection coil, and is disposed behind the coil assembly so as to extend along the axial direction of the case body inside the case body. A proximity sensor comprising: a processing circuit board; and a terminal assembly that includes at least a terminal pin for external connection, is electrically connected to the processing circuit board, and is disposed at a rear end of the processing circuit board. A manufacturing method comprising the following steps.
(A) The processing circuit board is assembled and fixed to the coil assembly, and the coil assembly on which the processing circuit board is assembled and fixed is assembled and fixed to the case body. Steps to prepare.
(G) The terminal portion of the first jig having the first reference position and the second reference position that are separated by a predetermined distance so that the predetermined position of the terminal portion assembly matches the first reference position. Positioning and setting the assembly.
(H) A step of positioning and setting the main body assembly on the first jig so that a predetermined position of the case body matches the second reference position.
(I) A step of fixing the terminal part assembly to the main body part assembly while maintaining the positioned state.
(J) A step of removing the first jig from the main body assembly and the terminal assembly.

  In the proximity sensor manufacturing method according to the second aspect of the present invention, in the step of positioning and setting the terminal assembly on the first jig (step (G) above), Preferably, the predetermined position of the terminal assembly to be matched with one reference position is the rear end of the terminal pin, and the step of positioning and setting the terminal assembly on the first jig In (step (H) above), the predetermined position of the case body to be matched with the second reference position is preferably the rear end of the case body.

  In the proximity sensor manufacturing method according to the second aspect of the present invention, the first jig has a first reference surface at the first reference position and a second reference surface at the second reference position. In this case, the step of positioning and setting the terminal assembly on the first jig (the step (G)) includes the rear end of the terminal pin as the first end. Preferably, the step of positioning and setting the main body assembly on the first jig (step (H)) is a rear end of the case body. Is preferably performed by abutting against the second reference plane.

  In the proximity sensor manufacturing method according to the second aspect of the present invention, in the state where the first jig is set to the terminal assembly, the first reference surface is placed behind the terminal pin. It is preferable to include a biasing member that biases in the direction of pressing against the end. In this case, the step of positioning and setting the terminal assembly on the first jig (step (G) above) ) Is preferably performed by abutting the rear end of the terminal pin of the terminal part assembly against the first reference plane by using a biasing force of the biasing member.

  In the method of manufacturing a proximity sensor according to the second aspect of the present invention, the first jig is in the state in which the terminal part assembly and the main body part assembly are set. And it is preferable that it is what is attached to the said main-body-part assembly.

  In the proximity sensor manufacturing method according to the first aspect and the second aspect of the present invention, the step of fixing the terminal part assembly to the main body part assembly (of (E) or (I) above) Step) is preferably performed by brazing the front ends of the terminal pins to a land provided on the processing circuit board with a brazing material.

In the proximity sensor manufacturing method according to the first aspect and the second aspect of the present invention, the proximity sensor is disposed behind the case body and the case body so as to surround the terminal assembly. It is preferable to further include a cylindrical holder member arranged on the same axis, and in that case, it is preferable that the manufacturing method of the proximity sensor further includes the following steps.
(K) The holder member is assembled to the rear end of the case body of the main body assembly to which the terminal assembly is assembled and fixed, and the first abutting surface provided on the holder member and the terminal assembly The holder member is fixed to the case body so that the terminal assembly is disposed inside the holder member while maintaining the state in contact with the second abutting surface provided in a three-dimensional shape. Step to do.

In the method for manufacturing a proximity sensor according to the first aspect and the second aspect of the present invention, it is preferable that the holder member is fixed to the case body by a resin sealing layer. In that case, the resin sealing layer is preferably formed by the following steps.
(L) A space formed in the main body assembly in which the terminal assembly is assembled and fixed and the holder member is assembled, via a resin inlet provided in the terminal assembly. A step of injecting a liquid resin material and curing the injected resin material to form a resin sealing layer.

  By employing the proximity sensor manufacturing method according to the present invention, it is possible to prevent the occurrence of variations in outer dimensions and easily manufacture a highly reliable proximity sensor.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. First, with reference to FIG. 1, the structure of the proximity sensor manufactured using the manufacturing method of the proximity sensor in Embodiment 1 and 2 of this invention mentioned later is demonstrated. FIG. 1 is a cross-sectional view of a proximity sensor manufactured using the proximity sensor manufacturing method according to Embodiment 1 or 2 of the present invention.

  As shown in FIG. 1, the proximity sensor 1 has a substantially cylindrical outer shape, a case body 10 having a front end and a rear end in the axial direction, and a holder member 20 disposed behind the case body 10. The coil assembly 30 disposed inside the case body 10 and at the front end of the case body 10, the terminal assembly 40 disposed inside the holder member 20, and the case assembly 10 are accommodated in the coil assembly. The processing circuit board 50 is mainly provided behind the solid body 30 and in front of the terminal assembly 40.

  The case body 10 is made of a metal cylindrical member. The holder member 20 includes a holder case 21 made of a metal cylindrical member and a receptacle 22 made of a resin cylindrical member. The receptacle 22 is press-fitted and fixed to the holder case 21. The holder member 20 is disposed coaxially with the case body 10 behind the case body 10, and is assembled and fixed in a state where the front end thereof is inserted into the rear end of the case body 10.

  The coil assembly 30 includes a core 31 made of a magnetic material, and a detection coil 32 and an auxiliary coil 33 formed by winding a coil wire (generally a copper wire). The detection coil 32 is accommodated in an annular recess provided in the front surface 31 a of the core 31, and the auxiliary coil 33 is accommodated in an annular recess provided in the front end of the outer peripheral surface of the core 31. The detection coil 32 is a coil that generates a magnetic field for detecting a detection target, and the auxiliary coil 33 is a magnetic field for adjusting the magnetic field of the detection coil 32 (more specifically, adjusting the direction of the magnetic field). Is a coil that generates The auxiliary coil 33 is generally called a cancel coil. The auxiliary coil 33 is connected in series with the detection coil 32, and the winding direction is opposite to the winding direction of the detection coil 32.

  The coil assembly 30 is housed inside a bottomed cylindrical coil case 12 and is arranged with the front surface 31 a of the core 31 in contact with the bottom of the coil case 12. The coil case 12 is press-fitted and fixed to the case body 10 so that the bottom thereof is positioned at the front end of the case body 10. As a result, the coil assembly 30 is disposed at the front end of the case body 10.

  The terminal assembly 40 includes a terminal pin 41 for external connection and a resin pin holder 42 that supports the terminal pin 41. The terminal pin 41 has a connection end 41 a located so as to protrude forward from the pin holder 42, and the connection end 41 a is electrically connected to the processing circuit board 50. The pin holder 42 has a resin inlet 42a at the center thereof. The terminal part assembly 40 is fitted and fixed in an opening provided in the receptacle 22 of the holder member 20.

  The processing circuit board 50 is made of a rigid board, and is disposed inside the case body 10 so as to extend along the axial direction of the case body 10. A processing circuit is formed on the processing circuit board 50. The processing circuit includes a detection circuit having the detection coil 32 and the auxiliary coil 33 described above as circuit elements, an output circuit for converting the output of the detection circuit into a voltage output or a current output of a predetermined specification, and power introduced from the outside Includes a power supply circuit that converts the signal into a predetermined power supply specification and outputs it to a detection circuit or the like. Here, the rigid board is a wiring board having high rigidity as typified by a glass-epoxy board, and is particularly suitable for mounting electronic components. The processing circuit board 50 has conductor patterns formed on the main surfaces 50a and 50b and inside thereof, and various kinds of the above-described various types of electronic components mounted on the main surfaces 50a and 50b are combined with these conductor patterns. A circuit is formed.

  The detection coil 32, the auxiliary coil 33, and the terminal pin 41 are electrically connected to the processing circuit provided on the processing circuit board 50. Specifically, the relay board 60 is used for electrical connection between the detection coil 32 and the auxiliary coil 33 and the processing circuit. The relay substrate 60 is formed of a flexible substrate, and includes a base 61 that is bonded and fixed to the back surface 31b of the core 31 of the coil assembly 30, and a plate-shaped shield portion 62 that is bonded and fixed to the front surface 31a of the core 31 of the coil assembly 30. And a cylindrical shield part 63 which is bent so as to surround a portion where the processing circuit of the coil assembly 30 and the processing circuit board 50 is provided. The base 61 of the relay board 60 is used for electrical connection between the detection coil 32 and the auxiliary coil 33 described above and the processing circuit. The plate-like shield part 62 and the cylindrical shield part 63 are parts for preventing intrusion of noise from the outside, and the conductor patterns provided in the plate-like shield part 62 and the cylindrical shield part 63 are stabilized. It is a part that exhibits an electrostatic shielding effect by being grounded to a potential.

  Here, the flexible substrate is a wiring substrate that is more flexible than the above-mentioned rigid substrate, and is formed, for example, by attaching a conductor pattern to the main surface of a base material made of polyimide resin with an adhesive or the like. Applicable. Since this flexible substrate is moderately flexible, it can be freely folded or folded, and can be used as a wiring substrate for relaying between electrical contacts. The base 61, the plate-like shield part 62, and the cylindrical shield part 63 described above are formed of a single flexible substrate, and are formed by bending a flexible substrate having a predetermined shape at a predetermined position. The

  As described above, the base 61 of the relay substrate 60 is bonded and fixed to the core 31. More specifically, the base 61 of the relay board 60 is fixed to the core 31 by bonding the main surface 61a of the base 61 of the relay board 60 and the back surface 31b of the core 31 via an adhesive part (not shown). . Here, a plurality of lands are provided on the main surface 61 b of the base 61 of the relay substrate 60. The coil end 32a of the detection coil 32 and the coil end 33a of the auxiliary coil 33 are connected to a predetermined land among these lands by soldering. The land is a bonding electrode provided in a part of the conductor pattern formed on the processing circuit board for realizing electrical connection. The lands are exposed on the surface of the processing circuit board, and terminal pins and lead wires are joined by soldering, pressure welding, or the like, thereby realizing electrical connection between these and the conductor pattern.

  A plurality of lands are also provided at portions near the front ends of the main surfaces 50 a and 50 b of the processing circuit board 50. The lands provided on the processing circuit board 50 are soldered in a state where the front end of the processing circuit board 50 is pressed against the base 61 of the relay board 60, so that a plurality of lands provided on the main surface 61 b of the base 61 are provided. Is connected to the designated land. The three-dimensional connection between the land provided on the processing circuit board 50 and the land provided on the base 61 is performed by a so-called cross-beam soldering method. In addition, the solder connection part connected by this girder soldering is shown with the code | symbol 35 in FIG. As described above, electrical connection between the detection coil 32 and the auxiliary coil 33 and the processing circuit is realized.

  The electrical connection between the terminal pin 41 and the processing circuit is such that the terminal pin 41 arranged on the land provided near the rear ends of the main surfaces 50a and 50b of the processing circuit board 50 so as to face the land. The connection end 41a is soldered. In FIG. 1, this solder connection portion is denoted by reference numeral 36.

  In addition, although the illustration is abbreviate | omitted in FIG. 1, the space inside the case body 10 and the holder member 20 is sealed with the resin sealing layer. The resin sealing layer is a layer for sealing the internal components of the proximity sensor 1, and is formed by injecting a liquid resin material into the space inside the case body 10 and the holder member 20 and curing it. Has been. The sealing with the resin sealing layer is performed for the purpose of preventing moisture and oil from entering the space inside the case body 10 and the holder member 20 from the outside, and at the same time in a vibration environment. It is also possible to prevent damage to internal components. In addition, as a resin material for sealing, a resin material containing a polyurethane resin or the like as a raw material is preferably used.

  Next, the operation of the proximity sensor having the above-described configuration will be described. A pulsed excitation current periodically flows through the detection coil 32. The frequency of this exciting current is, for example, several kHz. Thereby, the detection coil 32 and the auxiliary coil 33 are excited. A resistor (not shown) is connected to both ends of the detection coil 32.

  When the metal object as the detection object does not exist within the detectable range of the proximity sensor 1, the current flowing in the detection coil 32 itself after the supply of the excitation current to the detection coil 32 is interrupted It decreases rapidly due to the resistance connected at both ends. Therefore, when the metal body as the detection target does not exist within the detectable range of the proximity sensor 1, the voltage between both ends of the detection coil 32 is that of the detection coil 32 itself immediately after the supply of the excitation current is cut off. Although it increases due to the back electromotive force, it decays rapidly thereafter.

  On the other hand, when the metal body that is the detection target is present within the detectable range of the proximity sensor 1, if the supply of the excitation current to the detection coil 32 is interrupted, the magnetic field around the metal body Since (the magnetic field by the detection coil 32) changes, an eddy current is generated in the metal body. When the magnetic flux due to the eddy current passes through the detection coil 32, an induced voltage is generated in the detection coil 32. As a result, when a certain time (for example, several tens of microseconds) elapses from when the supply of the excitation current to the detection coil 32 is cut off, the induced voltage becomes dominant as the voltage across the detection coil 32. . Therefore, the presence / absence or position of the detection target can be detected by comparing the voltage across the detection coil 32 at this time with a threshold value.

  When the detection coil 32 is excited by the above-described method, the induced voltage reflects the time change of the eddy current flowing in the metal body. The detection coil 32 serves to convert the temporal change of the eddy current into a voltage. This voltage is not easily influenced by components having temperature dependency such as loss of the detection coil 32 and parasitic capacitance. Therefore, it is possible to provide a proximity sensor that is not easily affected by temperature changes during detection.

  The detection circuit may include an oscillation circuit having the detection coil 32 as a resonance circuit element and a discrimination circuit that binarizes the oscillation amplitude of the oscillation circuit with a threshold value. In this case, the proximity sensor 1 detects the decrease in the oscillation amplitude of the oscillation circuit and the stop of the oscillation that occur when the metal body as the detection object approaches the detection coil 32, thereby detecting the metal as the detection object. Detects the presence or position of the body. In such a system, an excitation current whose frequency changes continuously, for example, several hundred kHz (for example, the waveform is a sine wave) is applied to the detection coil 32.

  Next, with reference to FIG. 1, a mechanism for preventing variation in the outer dimension in the axial direction in the proximity sensor 1 having the above-described configuration will be described.

  As shown in FIG. 1, in the proximity sensor 1, the total length L <b> 1 that is the length from the front end of the case body 10 to the rear end of the holder member 20, and the length from the front end of the case body 10 to the rear end of the terminal pin 41. The length L2 needs to be within a predetermined range. In a conventional proximity sensor, the length L1 is adjusted by holding the holder member 20 against the case body 10 and the length L2 is adjusted against the holder member 20 with respect to the terminal member assembly 40. This was adjusted by.

  On the other hand, the present invention adjusts the size of the gap (distance D1 shown in the drawing) formed between the rear end of the processing circuit board 50 and the pin holder 42 by using a jig described later. The length L2 is adjusted so as to be within a predetermined range by fixing the terminal assembly 40 to the processing circuit board 50 and fixed in this way. By adjusting the holder member 20 against the subassembly 40, the total length L1 is adjusted to be within a predetermined range. As a result, variations in the dimensional accuracy of the components themselves (the coil case 12, the coil assembly 30, the relay substrate 60, and the processing circuit substrate 50) that are arranged side by side in the axial direction, and combinations of these components All the variations in the attaching accuracy are absorbed by the above-described gap, and the total length L1 and the length L2 fall within a predetermined range. As described above, since the holder member 20 is fixed to the terminal part assembly 40, the holder member 20 is not fixed between the holder member 20 and the case body 10, as shown in FIG. Gaps A and B are formed between these ends. That is, the insertion depth D2 of the holder member 20 with respect to the case body 10 is configured to be adjustable.

(Embodiment 1)
In the following, a detailed description will be given of a mechanism that prevents variations in the outer dimensions in the axial direction by specifically describing the method of manufacturing the proximity sensor according to the first embodiment of the present invention. 2 to 9 are a perspective view and a cross-sectional view for explaining the manufacturing method of the proximity sensor according to the first embodiment of the present invention.

  First, the main body assembly 70 shown in FIG. 2 is prepared. Specifically, the base 61 of the relay board 60 is bonded and fixed to the coil assembly 30, and the processing circuit board 50 is soldered to the base 61 of the relay board 60 bonded and fixed to the coil assembly 30. As a result, the coil assembly 30 and the processing circuit board 50 are assembled and fixed. Next, the coil assembly 30 to which the processing circuit board 50 is assembled and fixed is assembled and fixed inside the case body 10 using the coil case 14. More specifically, the coil assembly 30 to which the processing circuit board 50 is assembled and fixed is fixed to the coil case 14 using an adhesive or a sealing material, and then the coil assembly 30 is assembled and fixed. 14 is press-fitted and fixed to the case body 10 to obtain a main body assembly 70 as shown in FIG. In the state of the main body assembly 70, a portion near the rear end of the processing circuit board 50 protrudes from the rear end (the end located on the left side in the drawing) of the case body 10. The land 51 is located at the rear end of the processing circuit board 50 of the portion to be processed.

  Next, as shown in FIG. 3, the 1st jig | tool 80 is attached to the terminal part assembly 40 with which the terminal pin 41 and the pin holder 42 which were previously produced by insert molding were integrated. The terminal part assembly 40 has a cylindrical resin injection part 42 b provided integrally with the pin holder 42. The resin injection portion 42b extends along the direction in which the terminal pin 41 extends, and has a flange portion 42c at a predetermined position on the outer periphery thereof. The hollow portion of the resin injection portion 42 b communicates with a resin injection port 42 a provided in the pin holder 42.

  The first jig 80 has a holding part 81 and an urging part 85. The holding portion 81 is made of a cylindrical member having a hollow portion 82 that can receive the terminal portion assembly 40, and has an engaging portion 83 that can be inserted into the rear end of the case body 10 at one end thereof. Further, the holding portion 81 has a flange portion 84 at a predetermined position in the axial direction on the outer periphery thereof. The urging portion 85 includes a locking portion 86 made of a plate-like member and a coil spring 87 fixed to one main surface of the locking portion 86. The locking part 86 has a locking slit 86a.

  The terminal part assembly 40 is inserted into the hollow part 82 of the holding part 81 of the first jig 80. At that time, the terminal assembly 40 is inserted from the end of the holding portion 81 on the side where the engaging portion 83 is provided, and the resin injection portion 42b is on the side where the engaging portion 83 of the holding portion 81 is not provided. It is inserted so as to protrude from the end. A first reference plane P1 (see FIG. 6) is provided at a predetermined position on the inner wall surface that defines the hollow portion 82 of the holding portion 81, and the rear end of the terminal pin 41 abuts against the first reference plane P1. As a result, the terminal part assembly 40 is held against the holding part 81.

  A biasing portion 85 of the first jig 80 is further attached to the holding portion 81 of the first jig 80 in which the terminal assembly 40 is inserted. The biasing portion 85 is attached to the resin injection portion 42b of the terminal portion assembly 40 that is positioned to protrude from the end portion of the holding portion 81 where the engagement portion 83 is not provided, and the resin injection portion 42b is the locking portion. By rotating the locking portion 86 in a state where the locking portion 86 is inserted into the locking slit 86 a, the collar portion 42 c provided on the resin injection portion 42 b is locked to the locking portion 86. In this state, the coil spring 87 is maintained in a compressed state, and the state in which the rear end of the terminal pin 41 is pressed toward the first reference plane P1 is maintained by the biasing force.

  Next, referring to FIG. 4, the first jig 80 to which the terminal part assembly 40 is attached is attached to the main body part assembly 70. More specifically, the terminal part assembly 40 is attached to the main body part assembly 70 by inserting the engaging part 83 of the first jig 80 into the rear end of the case body 10 of the main body part assembly 70. The first jig 80 is attached. At this time, the rear end of the processing circuit board 50 that protrudes from the rear end of the case body 10 is received in the hollow portion 82 of the holding portion 81 of the first jig 80. The connection end 41a of the terminal pin 41 faces the land 51 provided at the rear end. In the above-described state in which the first jig 80 attached to the main body part assembly 70 is attached, the first jig 80 is not locked against the main body part assembly 70 and the like. The first jig 80 is in a state where its assembly position can be adjusted in the axial direction.

  Next, as shown in FIGS. 5 and 6, the main body assembly 70 to which the first jig 80 is attached is placed on the second jig 90. The second jig 90 includes a base portion 91 having a groove-shaped placement portion 92 provided on the upper surface, and a standing wall portion 93 provided at one end of the base portion 91. The main surface of the standing wall portion 93 on the side facing the mounting portion 92 corresponds to the third reference surface P3. When the main body assembly 70 is mounted on the mounting portion 92, the main surface is placed on the third reference surface P3. The main body assembly 70 is set so that the front end abuts against it.

  Next, while the main body assembly 70 is placed on the second jig 90 and the front end of the main body assembly 70 abuts against the third reference plane P3, the first jig with respect to the second jig 90 is maintained. The tool 80 is positioned. Specifically, by adjusting the insertion depth of the engaging portion 83 of the first jig 80 with respect to the rear end of the case body 10 of the main body assembly 70, the flange portion 84 of the first jig 80 is moved to the first position. (2) Affix to the end surface of the base portion 91 of the jig 90. Here, of the main surfaces of the flange portion 84, the main surface that presses against the end surface of the base portion 91 corresponds to the second reference surface P2, and the end surface of the base portion 91 corresponds to the fourth reference surface P4. To do.

  As shown in FIG. 6, in the state where the second reference surface P2 and the fourth reference surface P4 are in contact with each other, the distance between the first reference surface P1 and the fourth reference surface P4 is a predetermined distance. As a result, the distance from the front end of the main body assembly 70 to the rear end of the terminal pin 41 is maintained at a constant distance. By setting this distance to be a predetermined length L2, the size of the gap formed between the rear end of the processing circuit board 50 and the pin holder 42 is adjusted, so that the length L2 is reduced. The length is within a predetermined range.

  Next, soldering of the connection end 41a of the terminal pin 41 and the land 51 of the processing circuit board 50 is performed while maintaining the above state. As a result, electrical connection between the terminal pin 41 and the processing circuit is realized, and mechanical connection between the main body assembly 70 and the terminal assembly 40 is also realized.

  Next, as shown in FIG. 7, the first jig 80 and the second jig 90 are removed from the main body assembly 70 to which the terminal assembly 40 is assembled and fixed. More specifically, by rotating the locking portion 86 of the first jig 80, the lock of the flange portion 42c with respect to the locking portion 86 is released, and the first jig 80 is removed from the terminal assembly 40. The first jig 80 and the second jig 90 are removed from the main body assembly 70 to which the terminal assembly 40 is assembled and fixed by taking out the main body assembly 70 from the mounting portion 92 of the second jig 90. Remove. In FIG. 7, the illustration of the solder joint between the connection end 41 a of the terminal pin 41 and the land 51 of the processing circuit board 50 is omitted.

  Next, as shown in FIG. 8, the rear end of the case body 10 of the main body assembly 70 in which the terminal assembly 40 is assembled and fixed to the holder member 20 in which the receptacle 22 is press-fitted and fixed to the holder case 21 in advance. Assemble to. At this time, the holder member 20 is stopped by the first abutting surface 22 a (see FIG. 1) provided on the receptacle 22 abutting against the second abutting surface 42 d provided on the pin holder 42. In the state where the holder member 20 is abutted and assembled to the main body assembly 70, the insertion depth of the holder member 20 with respect to the case body 10 is adjusted by the abutment, and the case body in the combined state 10 and the length of the holder member 20, that is, the total length L1 of the proximity sensor 1 after completion is maintained within a predetermined range.

  Next, as shown in FIG. 9, a hopper 100 is attached to the tip of the resin injection portion 42 b while maintaining the state in which the holder member 20 is abutted and assembled to the main body assembly 70, and the hopper 100 Is used to inject a liquid resin material into the space inside the case body 10 and the holder member 20. Then, the injected resin material is cured. By the resin sealing layer formed in this curing step, the case body 10 positioned and assembled and the holder member 20 are bonded and fixed. Thereafter, the resin injection portion 42b is cut and removed at the base, whereby the proximity sensor 1 as shown in FIG. 1 is obtained.

  By using the method for manufacturing a proximity sensor according to the present embodiment described above, it is possible to provide a proximity sensor in which the occurrence of variations in outer dimensions is prevented. When the proximity sensor manufacturing method according to the present embodiment is used, there is no need for a configuration in which internal components that are spaced apart are connected to each other by a lead wire or a flexible substrate. Therefore, it is possible to provide a highly reliable proximity sensor and facilitate assembly work.

(Embodiment 2)
Below, the manufacturing method of the proximity sensor in Embodiment 2 of this invention is demonstrated concretely. In the proximity sensor manufacturing method according to Embodiment 1 of the present invention described above, the proximity sensor is manufactured using the second jig, thereby preventing the occurrence of variations in the external dimensions in the axial direction. However, in the method of manufacturing the proximity sensor according to the present embodiment, in view of the fact that the variation in the outer dimension in the axial direction of the case body 10 can actually be manufactured with sufficient accuracy, Use is omitted. 10 and 11 are a perspective view and a cross-sectional view for explaining the manufacturing method of the proximity sensor according to the second embodiment of the present invention. In addition, the detailed description is abbreviate | omitted here about the step similar to the manufacturing method of the proximity sensor in the above-mentioned Embodiment 1 of this invention, and the step according to the said manufacturing method.

  In the proximity sensor manufacturing method according to Embodiment 2 of the present invention, first, assembly work is performed in accordance with the above-described proximity sensor manufacturing method according to Embodiment 1 of the present invention. Specifically, the step of preparing the main body assembly 70, the step of attaching the terminal assembly 40 to the first jig 80, and the terminal assembly in the main assembly 70 shown in FIGS. Each step of attaching the first jig 80 to which 40 is attached is performed in accordance with the above-described method for manufacturing a proximity sensor according to the first embodiment of the present invention.

  Here, in the step of attaching the terminal part assembly 40 to the first jig 80, the first reference surface provided at a predetermined position on the inner wall surface that defines the hollow opening 82 of the holding part 81 of the first jig 80. By abutting the rear end of the terminal pin 41 against P <b> 1 (see FIG. 11), the terminal part assembly 40 is stopped against the holding part 81. Further, in the step of attaching the first jig 80 with the terminal part assembly 40 attached to the main body part assembly 70, the engaging part of the first jig 80 is attached to the rear end of the case body 10 of the main body part assembly 70. 83 is inserted, and the second reference surface P2 (see FIG. 11) provided at a predetermined position on the outer peripheral surface of the holding portion 81 of the first jig 80 is abutted against the rear end of the case body 10 to hold it. The main body assembly 70 is abutted against the portion 81. With the above-described stopper, both the terminal part assembly 40 and the main body part assembly 70 are positioned and attached to the first jig 80. The holding portion 81 of the first jig 80 does not need to be provided with the flange portion 84 (see FIGS. 10 and 11).

  As shown in FIG. 11, in a state where the terminal assembly 40 and the main assembly 70 are positioned and attached to the first jig 80, the first reference plane P1 and the second reference plane P2 Therefore, the distance from the rear end of the main body assembly 70 to the rear end of the terminal pin 41 is maintained at a constant distance. Here, as described above, since the variation in the outer dimension in the axial direction of the case body 10 hardly occurs, the distance from the front end of the main body assembly 70 to the rear end of the terminal pin 40 is a predetermined length L2. As a result, the size of the gap formed between the rear end of the processing circuit board 50 and the pin holder 42 is adjusted, and the length L2 becomes a length within a predetermined range.

  Next, soldering of the connection end 41a of the terminal pin 41 and the land 51 of the processing circuit board 50 is performed while maintaining the above state. As a result, electrical connection between the terminal pin 41 and the processing circuit is realized, and mechanical connection between the main body assembly 70 and the terminal assembly 40 is also realized. Each step performed thereafter is the same as that in the first embodiment.

  By using the proximity sensor manufacturing method according to the present embodiment described above, the same effect as that obtained when the proximity sensor manufacturing method according to the first embodiment described above is used can be obtained. Furthermore, since the number of jigs is reduced, the manufacturing operation is further facilitated, and the manufacturing cost can be further reduced.

  In the proximity sensor manufacturing method according to Embodiment 1 of the present invention described above, a partition, a step, a flange, or the like is provided at each of the first reference position to the fourth reference position of the first jig and the second jig. The case where it is set as the structure which provides a 1st reference surface thru | or a 4th reference surface by was illustrated. In the proximity sensor manufacturing method according to Embodiment 2 of the present invention described above, the first reference surface is provided by providing a partition, a step, or the like at each of the first reference position and the second reference position of the first jig. The second reference plane is provided. However, it is not always necessary to configure these reference positions on the surface for stopping. In other words, it is only necessary to adopt a configuration in which the relative mounting position of the parts with respect to the jig and the relative mounting position of the jigs can be accurately positioned, and it is naturally possible to use a method other than the stopper. .

  Further, the reference position in the first and second embodiments of the present invention described above is not limited to the position described above. These reference positions can be variously changed based on the shape of the jig, the shape of the proximity sensor to be manufactured, and the like. Actually, in the proximity sensor manufacturing method in the first embodiment and the proximity sensor manufacturing method in the second embodiment, the first reference position provided in the first jig is the same position, but the second reference position is the second position. The reference position is a different position.

  In the proximity sensor manufacturing method according to the first embodiment of the present invention described above, the main body assembly is attached to the second jig after the second jig to which the terminal assembly is attached is attached to the main body assembly. The case where the assembling work is performed in the order of placing the parts has been described as an example, but the main body assembly is first placed on the second jig, and then the terminal part assembly is attached. The assembly work may be performed in the order in which the two jigs are attached to the main body assembly. As described above, the work procedure can be variously changed as necessary.

  Thus, the above-described embodiments disclosed herein are illustrative in all respects and are not restrictive. The technical scope of the present invention is defined by the terms of the claims, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

It is sectional drawing of the proximity sensor manufactured using the manufacturing method of the proximity sensor in Embodiment 1 or 2 of this invention. It is a perspective view for demonstrating the manufacturing method of the proximity sensor in Embodiment 1 of this invention. It is a perspective view for demonstrating the manufacturing method of the proximity sensor in Embodiment 1 of this invention. It is a perspective view for demonstrating the manufacturing method of the proximity sensor in Embodiment 1 of this invention. It is a perspective view for demonstrating the manufacturing method of the proximity sensor in Embodiment 1 of this invention. It is sectional drawing for demonstrating the manufacturing method of the proximity sensor in Embodiment 1 of this invention. It is a perspective view for demonstrating the manufacturing method of the proximity sensor in Embodiment 1 of this invention. It is a perspective view for demonstrating the manufacturing method of the proximity sensor in Embodiment 1 of this invention. It is a perspective view for demonstrating the manufacturing method of the proximity sensor in Embodiment 1 of this invention. It is a perspective view for demonstrating the manufacturing method of the proximity sensor in Embodiment 2 of this invention. It is sectional drawing for demonstrating the manufacturing method of the proximity sensor in Embodiment 2 of this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 Proximity sensor, 10 Case body, 12 Coil case, 20 Holder member, 21 Holder case, 22 Receptacle, 22a 1st contact surface, 30 Coil assembly, 31 Core, 31a Front surface, 31b Back surface, 32 Detection coil, 32a Coil end 33, auxiliary coil, 33a coil end, 35, 36 solder joint, 40 terminal assembly, 41 terminal pin, 41a connection end, 42 pin holder, 42a resin injection port, 42b resin injection port, 42c collar, 42d second Butting surface, 50 processing circuit board, 50a, 50b main surface, 51 land, 60 relay substrate, 61 base, 61a, 61b main surface, 62 plate shield part, 63 cylindrical shield part, 70 body part assembly, 80 1 jig, 81 holding part, 82 hollow part, 83 engaging part, 84 flange part, 85 Biasing part, 86 Locking part, 86a Locking slit, 87 Coil spring, 90 Second jig, 91 Base part, 92 Placement part, 93 Standing wall part, 100 Hopper, P1 First reference plane, P2 Second reference Plane, P3 third reference plane, P4 fourth reference plane.

Claims (13)

A cylindrical case body having a front end and a rear end in the axial direction;
A coil assembly including at least a detection coil and disposed inside the case body and at a front end of the case body;
A processing circuit board electrically connected to the detection coil and disposed behind the coil assembly so as to extend along the axial direction of the case body inside the case body;
A method of manufacturing a proximity sensor comprising at least a terminal pin for external connection, and a terminal assembly that is electrically connected to the processing circuit board and disposed at a rear end of the processing circuit board,
The processing circuit board is assembled and fixed to the coil assembly, and the body assembly is prepared by assembling and fixing the coil assembly on which the processing circuit board is assembled and fixed to the case body. Steps,
The terminal part assembly is placed on a first jig having a first reference position and a second reference position that are separated by a predetermined distance so that the predetermined position of the terminal part assembly matches the first reference position. Positioning and setting; and
The main body assembly is mounted on a second jig having a third reference position and a fourth reference position that are separated by a predetermined distance so that the predetermined position of the main body assembly matches the third reference position. Positioning and setting; and
Position the first jig on which the terminal assembly is set and the second jig on which the body assembly is set so that the second reference position and the fourth reference position match. Step to set and
Fixing the terminal part assembly to the body part assembly while maintaining the positioned state;
And a step of removing the first jig and the second jig from the body part assembly and the terminal part assembly. In the step of positioning and setting the terminal part assembly on the first jig, the predetermined position of the terminal part assembly to be matched with the first reference position is a rear end of the terminal pin,
In the step of positioning and setting the main body assembly on the second jig, the predetermined position of the main body assembly to be matched with the third reference position is a front end of the main body assembly. The method for manufacturing a proximity sensor according to claim 1. The first jig has a first reference surface at the first reference position and a second reference surface at the second reference position;
The second jig has a third reference surface at the third reference position and a fourth reference surface at the fourth reference position,
The step of positioning and setting the terminal assembly on the first jig is performed by abutting the rear end of the terminal pin against the first reference plane,
The step of positioning and setting the main body assembly on the second jig is performed by abutting the front end of the main assembly on the third reference plane,
The step of positioning and setting the first jig on which the terminal part assembly is set and the second jig on which the main body part assembly is set includes the second reference surface and the fourth reference surface. The method for manufacturing a proximity sensor according to claim 2, wherein the proximity sensor is abutted against each other. The first jig includes a biasing member that biases the first reference surface in a direction in which the first reference surface is pressed against a rear end of the terminal pin in a state where the terminal assembly is set.
The step of positioning and setting the terminal assembly on the first jig uses the biasing force of the biasing member to place the rear end of the terminal pin of the terminal assembly in the first reference plane. The method of manufacturing a proximity sensor according to claim 3, wherein the proximity sensor is performed by striking the sensor. The first jig is attached to the terminal part assembly in a state where the terminal part assembly is set,
The proximity sensor manufacturing method according to claim 1, wherein the second jig is placed on the main body assembly in a state where the main body assembly is set. A cylindrical case body having a front end and a rear end in the axial direction;
A coil assembly including at least a detection coil and disposed inside the case body and at a front end of the case body;
A processing circuit board electrically connected to the detection coil and disposed behind the coil assembly so as to extend along the axial direction of the case body inside the case body;
A method of manufacturing a proximity sensor comprising at least a terminal pin for external connection, and a terminal assembly that is electrically connected to the processing circuit board and disposed at a rear end of the processing circuit board,
The processing circuit board is assembled and fixed to the coil assembly, and the body assembly is prepared by assembling and fixing the coil assembly on which the processing circuit board is assembled and fixed to the case body. Steps,
The terminal part assembly is placed on a first jig having a first reference position and a second reference position that are separated by a predetermined distance so that the predetermined position of the terminal part assembly matches the first reference position. Positioning and setting; and
Positioning and setting the main body assembly on the first jig so that a predetermined position of the case body matches the second reference position;
Fixing the terminal part assembly to the body part assembly while maintaining the positioned state;
And a step of removing the first jig from the body part assembly and the terminal part assembly. In the step of positioning and setting the terminal part assembly on the first jig, the predetermined position of the terminal part assembly to be matched with the first reference position is a rear end of the terminal pin,
The step of positioning and setting the terminal assembly on the first jig, the predetermined position of the case body to be matched with the second reference position is a rear end of the case body. The manufacturing method of the proximity sensor as described in 2. above. The first jig has a first reference surface at the first reference position and a second reference surface at the second reference position;
The step of positioning and setting the terminal assembly on the first jig is performed by abutting the rear end of the terminal pin against the first reference plane,
The proximity sensor manufacturing method according to claim 7, wherein the step of positioning and setting the main body assembly on the first jig is performed by abutting a rear end of the case body against the second reference surface. Method. The first jig includes a biasing member that biases the first reference surface in a direction in which the first reference surface is pressed against a rear end of the terminal pin in a state where the terminal assembly is set.
The step of positioning and setting the terminal assembly on the first jig uses the biasing force of the biasing member to place the rear end of the terminal pin of the terminal assembly in the first reference plane. The method of manufacturing a proximity sensor according to claim 8, wherein the proximity sensor is performed by striking the sensor.   The said 1st jig | tool is attached to the said terminal part assembly and the said main-body part assembly in the state in which the said terminal-part assembly and the said main-body part assembly were set, Any of Claim 6 to 9 A method for manufacturing the proximity sensor according to claim 1.   The step of fixing the terminal part assembly to the main body part assembly is performed by brazing a front end of the terminal pin to a land provided on the processing circuit board with a brazing material. The manufacturing method of the proximity sensor in any one of. The proximity sensor further includes a cylindrical holder member disposed behind the case body and coaxially with the case body so as to surround the terminal part assembly,
The holder member is assembled to the rear end of the case body of the main body assembly to which the terminal assembly is assembled and fixed, and the first abutting surface provided on the holder member and the terminal assembly are provided. A step of fixing the holder member to the case body so that the terminal assembly is disposed inside the holder member while maintaining the state where the second abutting surface is abutted. The method for manufacturing a proximity sensor according to claim 1, further comprising: In the space formed in the main body assembly in which the terminal assembly is assembled and fixed and the holder member is assembled, a liquid is introduced through a resin inlet provided in the terminal assembly. Injecting a resin material and further comprising forming a resin sealing layer by curing the injected resin material,
The proximity sensor manufacturing method according to claim 12, wherein the holder member is fixed to the case body by the resin sealing layer.

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