JPH0927256A - Detector - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the diameter of a detector and to enhance soldering work and product reliability. SOLUTION: Two grooves 21, 22 for laying the conductors 11, 12 of a coaxial cable 1 are formed on a base 2 made of an insulating material. Lands 21a, 22a for connecting the conductors 11, 12 by soldering are formed on at least part of the inner surfaces of the grooves 21, 22.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to an elongated rod-shaped detector.

[0002]

2. Description of the Related Art In recent years, photoelectric detectors have a diameter of 3 mm to
Some are downsized to about several mm. An example of such a photoelectric detector is shown in FIG. In FIG. 6A,
The core wire (center conductor) 101 and the shield wire (outer conductor) 102 of the coaxial cable 100 are soldered to a printed circuit board (base) 103, respectively. An electronic component 1 such as a chip resistor is provided on the printed circuit board 103.
04 is mounted, and two leads 105a and 105b of the PD (photodiode) 105 are soldered. The PD 105 and the like are wrapped with a metal plate 106 for shielding, and then the metal sleeve 1 for protection is used.
It is stored in 07. The metal sleeve (cylindrical body) 1
A lens 108 is attached to the tip of 07.

[0003]

However, in the above-mentioned prior art, since the shielded wire 102 of the coaxial cable 100 is exposed and twisted, the shielded wire 102 is soldered to the substrate 103, so that the number of man-hours required for manual work increases. . Furthermore, in the conventional photoelectric detector, the coaxial cable 1
When the core wire 101 and the shield wire 102 of No. 00 are soldered, the printed circuit board 103 is flat as shown in FIG. 6B, so that the solder 109 easily flows on the surface of the board 103, and the core wire 101 and the shield wire 102 are shielded. Line 102,
It is inevitable that the positioning accuracy of the land of the substrate 103 with respect to the terminal surface (not shown) is deteriorated. Therefore, the substrate 1
Since the width W of 03 becomes large, the photoelectric detector cannot be made sufficiently thin. Moreover, the workability of soldering is poor, and there is a risk of short-circuiting. Such a problem similarly occurs in detectors such as proximity switches other than photoelectric detectors. Therefore, the main object of the present invention is to reduce the diameter of the detector and to improve the workability of brazing and the reliability of the product.

Further, in the above-mentioned prior art, since the metal plate 106 for shielding is wound, the number of assembling steps is large and the outer diameter of the detector is also large.

Further, since the leads 105a and 105b of the PD 105 are soldered to the substrate 103, the PD 105
It is inevitable that the optical axis of the lens 107 and the axis of the sleeve 107 are slightly deviated from each other, so that the optical axes of the lens 108 and the PD 105 are likely to deviate from each other.

The present invention can deal with such other problems as will be described later in the embodiments of the invention.

[0007]

In order to achieve the above-mentioned main object, the present invention forms a base into a rod shape, and the base has a first groove and a groove width wider than that of the first groove. The narrow second groove is formed on the same axis, and the terminal surface is formed on at least a part of the inner surfaces of both grooves. In the coaxial cable brazed to the base, the center conductor is exposed, and the outer conductor is exposed while covering the first covering material. The outer conductor and the center conductor are respectively exposed to the first and second conductors. It is brazed to the terminal surface while being laid in the groove.

When the coaxial cable is connected to the terminal surface of the base, the conductor is dropped into the groove, and the terminal surface on the inner surface of the groove and the conductor are brazed with the conductor along the groove. Therefore, the conductor positioning accuracy is good, and since the solder (the solder) stays in the groove, the brazed portion becomes compact, so that the detector can be made thin and the soldering reliability is high, and There is no risk of short circuit.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below by taking a photoelectric detector as an example. 1 and 2 are enlarged views of the first embodiment. As shown in FIG. 1, a coaxial cable 1 concentric with one axis includes a shield wire (outer conductor) 11 and
A core wire (center conductor) 12, a first coating material 13 that insulates between the two wires 11 and 12, and a second coating material that covers the shielded wire 11.
It is composed of a covering material 14. At the tip of the coaxial cable 1, the core wire 12 is exposed and the shielded wire 11
Are exposed in a state of covering the first covering material 13, and
Since the outer peripheral surface of the first covering material 13 is exposed between the two wires 11 and 12, the core wire 12 and the shield wire 11 are separated from each other in the axial direction.
The insulation between 12 is secured. The coaxial cable 1 is fixed to a molded base 2 as described later.

The base 2 is a kind of so-called three-dimensional substrate, and has a round bar shape as a whole and is made of an insulating material such as synthetic resin (for example, liquid crystal polymer). U-shaped first, second, and third grooves 21, 22, and 23 are formed in the base 2 on the same axis along the longitudinal direction of the base 2. First, second and third grooves 21, 22, 2
2 (d) and 2 (e) in a state in which the shield wire 11, the core wire 12 and the first coating material 13 have been dropped into each of FIG.
It is stored like.

First and second lands 21a and 22a to be terminal surfaces are formed integrally with the base 2 on the inner surfaces of the first and second grooves 21 and 22 of FIG. On the other hand, on the outer peripheral surface of the base 2, a shield (metal for shielding) 2 made of metal foil is provided on a portion excluding the insulating protrusions 24.
5 are integrally formed. In FIG. 1, the portions corresponding to the surfaces of the shield 25 and the lands 21a and 22a are shaded. Further, the thickness of the shield 25 is not drawn in order to make the drawings easy to see.

As shown in FIG. 2 (e), the first groove 21 has a groove width slightly wider than that of the shield wire 11, while the second groove 22 has a groove width slightly wider than that of the core wire 12. . Therefore, the groove width of the second groove 22 is narrower than that of the first groove 21. The shield wire 11 is the land 21 of the first groove 21.
On the other hand, the core wire 12 is soldered and connected to the land 22a of the second groove 22. The shield wire 11 is electrically connected to the shield 25 via the land 21a.

The first groove 21, the third groove 23, and the second groove 22 are formed in this order from the base end face 2a of the base 2 toward the base end, and the cross section of FIG. As clearly shown in the plan view, the bottom of each groove has a semicircular shape with the O point at the center.

As shown in FIG. 2B, a recess 26 is formed at the tip 2b of the base 2 in the longitudinal direction. On the bottom surface of the recess 26, a light emitting element 3 such as an LED is housed and a first wiring pattern is formed.
And the 2nd electric circuits 27 and 28 are formed. The light emitting element 3 is connected and fixed to the electrode of the second electric path 28 by soldering, and the second electric path 28 is connected to the second electric path 28 by a second electrode.
To the land 22a. On the other hand, the first electric line 27
The electrode and the light emitting element 3 are electrically connected by a wire (gold wire) 4. These electric lines 27, 28, lands 21a,
22a and the shield 25 are formed by electroless plating, electroplating, or the like. The base 2 is molded by injection molding once or plural times as required. The lands 21a and 22a may be formed by inserting thin metal plates by insert. A lens 5 made of transparent resin is provided in the recess 26.

A cylindrical metal sleeve (cylindrical body) 6 is mounted on the outer periphery of the base 2 as shown in FIG. 2 (e).
The above-mentioned insulating projections 24 project outward from the outer surface of the base 2, and are provided in plural in both the axial direction and the radial direction as shown in FIGS. An insulating space S is held between the sleeve 6 and the shield 25. The metal sleeve 6 is for protecting the detector.

In the above structure, the lands 21a, 22a
Since the first and second grooves 21 and 22 having the above are arranged on the same axis, it is not necessary to strip the shield wire 11 from the first covering material 13 and twist the shield wire 11 and The shielded wire 11 can be soldered to the land 21a in a state where the shield wire 11 is covered. Therefore, the man-hours required for soldering are reduced.

In the detector of FIG. 1, lands 21a and 22a are provided on the inner surfaces of the grooves 21 and 22, respectively. for that reason,
The coaxial cable 1 can be dropped into the grooves 21 to 23, and the shielded wire 11 and the core wire 12 can be soldered along the first and second grooves 21 and 22, respectively. Therefore, positioning of the shield wire 11 and the core wire 12 is easy, and there is no fear that the solder will protrude from the grooves 21 and 22. As a result, the width of the lands 21a and 22a required for soldering becomes small, so that the detector can be made thin, and the workability of soldering is improved, and there is no risk of short-circuiting, and product reliability is improved. Also improves.

Although the shield wire 11 is removed from the portion of the first coating material 13 accommodated in the third groove 23, the shield wire 11 can be easily shielded by using a cutter that cuts only the shield wire 11. Line 11 can be eliminated.

Further, in this embodiment, since the shield 25 is formed on the outer peripheral surface of the rod-shaped base 2 as shown by the diagonal lines, the number of assembling steps is larger than that of winding the conventional metal plate 106 (FIG. 7). And the outer diameter of the detector becomes smaller.

Further, in this embodiment, the insulating projection 24 is provided.
Is provided to form a space S between the shield 25 of the base 2 and the metal sleeve 6 of FIG. Therefore,
Insulation can be achieved without increasing the size of the detector.

Further, as shown in FIG. 2B, since the recess 26 is formed in the base 2 and the lens 5 is directly attached to the base 2, the optical axes of the light emitting element 3 and the lens 5 are misaligned. There is no danger of it occurring.

By the way, although the base 2 has a round bar shape in the above-described embodiment, the base 2 may have a rectangular bar shape as shown in FIGS. 3 (a) to 3 (c).

The cross-sectional shapes of the grooves 21 and 22 do not have to be semicircular or U-shaped, and the rectangular shape shown in FIG.
It may have a shape as shown in FIG. further,
As shown by the chain double-dashed line in FIG. 4B, the shield wire 11 does not have to be completely housed in the first groove 21.

In the above embodiment, the projector having the light emitting element 3 shown in FIG. 3 has been described, but the present invention can be applied to the light receiver having the light receiving element in the recess 26.
Further, it can be applied to a photoelectric detector having both the light emitting element and the light receiving element in the recess 26. in this case,
As shown in FIGS. 5A and 5B, a pair of first to third grooves 21 to 23 is provided.

Furthermore, the present invention can be applied to detectors other than photoelectric detectors, for example, detectors such as proximity switches. In the present invention, the detector is a concept including, for example, one of a light emitter and a light receiver of a photoelectric detector, a set of a light emitter and a light receiver, and a light emitter and a light receiver.

Further, although the third groove 23 is provided in the above embodiment, the third groove 23 is not necessarily provided.
The lands 21a and 22a may be formed on the entire surfaces of the grooves 21 and 22 or may be formed on a part thereof. Also, "brazing" using a metal other than solder may be performed.

[0027]

As described above, according to the present invention,
Since the pair of grooves having the terminal surface and having different groove widths are arranged on the same axis, the core wire and the shield wire of the coaxial cable can be welded without exposing and twisting the shield wire. Therefore, the troublesome work of stripping and twisting the shield wire becomes unnecessary. Further, since the terminal surface is provided on the inner surface of the groove, the conductor is positioned by the groove, which facilitates the positioning of the conductor and prevents the solder (solder) from protruding from the groove. Therefore,
It is possible to further reduce the diameter of the thin detector, improve the workability of brazing, and eliminate the risk of short-circuiting, thus improving the reliability of the product.

Further, in the invention of claim 2, since the metal for shielding is integrally formed on the outer peripheral surface of the base,
Not only the labor for winding the shield plate can be saved, but also the diameter can be further reduced.

Further, according to the invention of claim 3, since the insulating projection is provided to insulate the shield and the metal sleeve from each other, the outer diameter of the photoelectric detector does not become thicker.
Insulation can be achieved.

Further, if the outer peripheral surface of the first coating material is exposed between the central conductor and the outer conductor, both conductors are separated in the axial direction, so that the reliability of insulation between both conductors is improved.

[Brief description of drawings]

FIG. 1 is an enlarged exploded perspective view showing a detector according to a first embodiment of the present invention.

2A is a sectional view taken along line aa of FIG. 2B, FIG. 2B is a longitudinal sectional view of a base, FIG. 2C is a right side view, and FIG. 2D is a sectional view taken along line dd of FIG. FIG. 1E is a vertical sectional view of the photoelectric detector.

FIG. 3 is an enlarged front view of a photoelectric detector showing a second embodiment,
It is a longitudinal sectional view and a transverse sectional view.

FIG. 4 is an enlarged cross-sectional view showing another shape of the groove.

FIG. 5 is an enlarged front view and bottom view of a photoelectric detector showing a third embodiment.

FIG. 6A is an exploded vertical sectional view showing a conventional photodetector,
(B) is a cross-sectional view of the substrate.

[Explanation of symbols]

 1: Coaxial cable 11: Shield wire (outer conductor) 12: Core wire (center conductor) 13: First covering material 14: Second covering material 2: Base 21: First groove 22: Second groove 21a, 22a: Land (terminal surface) 24: Insulation protrusion 25: Shielding metal 26: Recesses 27, 28: Electric path 3: Light emitting element 6: Metal sleeve

Claims (6)

[Claims] 1. A coaxial cable comprising a center conductor, an outer conductor, a first coating material for insulating between the both conductors, and a second coating material for coating the outer conductor, and a long cable made of an insulating material. In a detector in which a terminal is attached to the terminal surface of the base, a detection element is provided at the tip of the base in the longitudinal direction, and a cylindrical body is attached to the outside of the base, the base is formed into a rod shape. A first groove and a second groove having a groove width narrower than the first groove are formed on the same axis in the base, and at least a part of the inner surfaces of the both grooves are respectively formed. The terminal surface is formed, the coaxial cable, the central conductor is exposed, the outer conductor is exposed in a state of covering the first coating material, the outer conductor and the central conductor, respectively, The terminal surface in a state of being laid in the first and second grooves. A detector characterized by being brazed to. 2. The detector according to claim 1, wherein a shielding metal is integrally formed on the outer peripheral surface of the base. 3. The insulating space according to claim 2, wherein a plurality of insulating projections projecting outward are integrally formed on the outer periphery of the rod-shaped base, and the insulating space is provided between the cylindrical body and the shielding metal. Is held by the detector. 4. The recess according to claim 2, wherein a recess is formed at the tip of the rod-shaped base, and the detection element is housed in the recess, so that at least one of the outer periphery of the element is surrounded. A detector whose part is covered with the metal for the shield. 5. The coaxial cable according to claim 1, wherein the outer peripheral surface of the first covering material is exposed between the center conductor and the outer conductor, so that the exposed portion of the center conductor and the outer conductor is exposed. Detectors separated in the axial direction. 6. The device according to claim 1, 2, 3, 4 or 5, wherein at least one of a light emitting element and a light receiving element of a photoelectric detector is provided as the detection element, and the base is connected to the terminal surface. A detector in which an electric path is formed, and at least one of the light emitting element and the light receiving element is connected to and fixed to an electrode of the electric path.