JP2004120358A - Antenna for radio communication - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce fluctuations in characteristics and to reinforce the mechanical strength of an element and a cable soldering portion not to cause a cost increase. <P>SOLUTION: A printed board 1 is provided with notch portions 7. A case 5 made of a resin is provided with claw portions 6 locking into the notch portions 7. In addition, the case 5 made of the resin is provided with a recessed portion 8 for the element fixing the element 3 and a recessed portion 9 for a cable fixing the cable 4. Then, the case 5 made of the resin is mounted to cover the element 3, a balun circuit portion 2, and the cable 4 on the printed board. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an antenna for wireless communication, and more particularly, has a short element length, is installed in tens to hundreds of houses in an area where it is housed in a housing, and is used for information and control of failure or abnormality of equipment. The present invention relates to a wireless communication antenna of a wireless master device in a 1: N wireless system for communicating information and the like with a management center via a 400 MHz band wireless communication.
[0002]
[Prior art]
The wireless base station, which is attached to a telephone pole or messenger wire like a wireless master unit, has a communication antenna housed inside the body of the base station, so that it does not give a sense of discomfort or distrust to the local people. There are cases. An example of a communication antenna used in such a wireless master device will be described with reference to FIG. FIG. 4 is a perspective view of a communication antenna to be housed inside the housing.
[0003]
In FIG. 4, the antenna element (right) 3a and the antenna element (left) 3b are inserted and soldered to a printed circuit board 16 having a balun circuit portion 2 made of copper foil, and the element retainer 17 is soldered. Fixed. One of the cables 4 is connected to the balun circuit section 2 of the printed circuit board 16 by insertion and soldering so as to be connected to the communication device section of the master unit body. The balun circuit portion 2 of the printed circuit board 16 and the soldered portion of the cable 4 are provided with a moisture-proof coating 18 for preventing the characteristics from largely changing when water droplets adhere to the device due to dew condensation or the like. Further, the cable 4 is screwed and fixed to the printed circuit board 16 by the fixture 19.
[0004]
[Problems to be solved by the invention]
However, in the above-described conventional configuration, the balun circuit portion formed on the printed circuit board is particularly susceptible to the resin housing housing the communication antenna, and particularly when the distance from the housing cannot be greatly separated, Antenna characteristics change greatly due to variations in the mounting position and the distance due to the tolerance of the finished resin housing.Therefore, the mounting position of the antenna is restricted. There was a problem that miniaturization was hindered.
[0005]
Also, in order to prevent the characteristics from changing due to dust and dirt adhering to the balun during operation and to prevent disconnection due to the tensile stress of the cable, it is necessary to fix the cable with fixing brackets, etc. There has been a problem that the cost is increased due to an increase in man-hours, and furthermore, the soldered portion of the element is broken or disconnected due to stress such as vibration or temperature change.
[0006]
The present invention suppresses the influence on the antenna characteristics due to the resin housing housing the wireless communication antenna, solves the problems such as disconnection due to the soldered portion of the element and the stress of the cable, and eliminates the cost increase for fixing. It is another object of the present invention to provide a wireless communication antenna that is housed inside an antenna and that further improves the quality of the moisture-proof coating operation.
[0007]
[Means for Solving the Problems]
In order to solve the above problems, the present invention provides an insertion hole or a notch in a printed circuit board, a resin case that engages with the insertion hole or the notch, and a fixing claw. A resin case configured to cover an element for radio wave transmission, a balun circuit, and a cable is positioned, inserted, and fixed.
[0008]
According to the present invention, variations in antenna performance can be reduced, restrictions on the mounting position can be reduced, and proper arrangement and downsizing of the housing can be realized.
[0009]
BEST MODE FOR CARRYING OUT THE INVENTION
According to a first aspect of the present invention, there is provided a printed circuit board having a balun circuit for mounting and connecting a radio wave transmitting element and the element for matching with a wireless device to which the antenna of the present invention is connected, and connecting to the printed circuit board. It is equipped with a cable for the purpose of connecting to a wireless device, and is further provided with a resin case that covers the radio wave transmission element on the printed circuit board, the balun circuit section and the cable in a close state, and positions the resin case on the printed circuit board. -It is configured to be fixed.
[0010]
As a result, the portion that directly touches during operation or the like is reduced, so that it is possible to prevent a change in characteristics due to stress and adhesion of dust and dirt, and the balun circuit portion is more susceptible to the influence of the dielectric constant of the resin as the distance becomes shorter. By taking advantage of this fact, it is possible to reduce the influence of the dielectric constant of the housing that houses the wireless communication antenna, thereby reducing variations in antenna performance and reducing the restrictions on the mounting position of the wireless communication antenna. Can be downsized.
[0011]
According to a second aspect of the present invention, the printed circuit board is provided with an insertion hole or a notch, and the resin case facing the insertion hole or the notch is provided with a fixing claw to be inserted and locked on the printed circuit board. Is what you do.
[0012]
Thereby, the positioning and fixing of the resin case can be easily performed, so that it is possible to prevent an increase in cost due to additional parts and an increase in man-hours.
[0013]
According to a third aspect of the present invention, the resin case is provided with a concave portion for fixing the radio wave transmission element between the resin case and the printed circuit board, and the resin case is fitted and fixed to the printed circuit board and the element is fixed at the same time. It is configured.
[0014]
As a result, the element can be fixed without adding any additional parts and at the same time as the insertion and fixing of the resin case.Addition of parts and additional man-hours for disconnection and fixing of the soldered part of the element due to stress during work etc. Cost can be prevented.
[0015]
Further, the invention according to claim 4 is configured such that a concave portion for fixing a cable between the resin case and the printed circuit board is provided, and the cable is fixed at the same time as the resin case is fitted and fixed to the printed circuit board. Things.
[0016]
As a result, the cable can be fixed without adding additional parts and at the same time as the insertion and fixing of the resin case, and the parts with low mechanical strength such as the soldered part and the core part of the cable due to tensile stress during work etc. In addition, it is possible to prevent disconnection of the wire and to prevent cost increase due to addition of parts for fixing and increase in man-hours.
[0017]
The invention according to claim 5 is such that the resin case is formed into a container shape so as to enclose the printed circuit board, and in a state where the printed circuit board is fixed, a coating material is injected and cured into the resin case to form a necessary portion of the printed circuit board. Has a moisture-proof structure, and is configured to fix the element and the cable.
[0018]
As a result, the accuracy of the application position and thickness of the moisture-proof coating is improved, and the overflow and dripping of the coating material can be prevented, so that the work management up to curing can be facilitated. Further, since the element and the cable are also fixed by the coating, it is possible to prevent an increase in cost due to additional parts for fixing and an increase in man-hours.
[0019]
【Example】
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0020]
(Example 1)
1 and 2 are perspective views showing a wireless communication antenna according to a first embodiment of the present invention. FIG. 1 is a perspective view before assembly, and FIG. 2 is a perspective view after assembly. In FIG. 1, 1 is a printed circuit board, 2 is a balun circuit portion formed of copper foil on the printed circuit board, 3a and 3b are arranged on the printed circuit board, and are 波長 wavelengths connected to the balun circuit portion by soldering. The left and right elements of the dipole antenna, 4 are connected to the balun circuit by soldering, a cable for connecting to the communication equipment, 5 is a radio wave transmission element on the printed circuit board and the balun circuit and the cable in close proximity. A resin case inserted and fixed to the printed circuit board so as to cover it, 6 is provided in the resin case, and a claw portion that fits with a notch 7 provided on the opposing printed circuit board, and 8 is provided in the resin case. The reference numeral 9 denotes a concave portion for fixing the element, and 9 denotes a concave portion for fixing the cable provided in the resin case.
[0021]
The claw portion 7 is aligned with the cutout portion 7 of the printed circuit board 1 to which the antenna elements 3a and 3b and the cable 4 are fixed by soldering, and the resin case 6 is inserted and fitted to cover the balun circuit portion. At this time, since the fixing concave portions 8 of the elements 3a and 3b of the resin case 6 have the same size as the diameters of the elements 3a and 3b, the elements 3a and 3b are located between the printed circuit board 1 and the element fixing concave portions 8 of the resin case 6. 3b is fixed. In the same manner, the resin concave portion 9 of the cable 4 of the resin case 6 has the same size as the diameter of the cable 4, and the cable 4 is aligned with the position of the concave portion 9 of the resin case 6. The cable 4 is fixed by inserting and fitting the cable 6 into the printed circuit board 1.
[0022]
As described above, when the resin case is provided with the claw portion, the concave portion for fixing the element, and the concave portion for fixing the cable, which are fitted to the cutout portion provided on the printed circuit board, and the resin case is inserted into the printed circuit board. At the same time, the element and the cable are fixed so that there is no need to take measures against stress, adhesion of dirt or dirt, restrict the mounting position of the antenna, or add additional components to fix the element or cable. It is possible to solve the problem that it is difficult to reduce the size of the housing, the disconnection of the soldered portion of the element or the cable due to the stress, and the increase in cost due to the addition of components and man-hours for the countermeasure.
[0023]
FIG. 3 is a perspective view showing the configuration of a wireless communication antenna having a moisture-proof coating according to the present embodiment. The same components as those in FIG. 1 are denoted by the same reference numerals and description thereof will be omitted. In FIG. 3, reference numeral 10 denotes a resin case in which a printed circuit board 11 is inserted and fixed, and is formed in a container shape so as to enclose the entire printed circuit board 11. An insertion groove for passing 3a and 3b, 13 is an insertion groove for passing the cable 4 in the same manner, and 14 is a resin case 10 in which the printed circuit board 11 is inserted and fixed. Is a high-viscosity coating material for filling the gap so that the moisture-proof coating material 15 does not protrude from the insertion grooves 12a, 12b, and 13 of the elements 3a and 3b and the cable 4 when the moisture-proof structure is used.
[0024]
The printed circuit board 11 is inserted into and fixed to the insertion grooves 12a, 12b, and 13 of the resin case 10 with the elements 3a and 3b and the cable 4 aligned, and the elements 3a and 12b are inserted into the insertion grooves 12a, 12b, and 13 of the resin case 10. A high-viscosity coating material 14 is applied so as to fill the gap between 3b and the cable and prevent the moisture-proof coating material 15 from protruding. Next, a moisture-proof coating material 15 is injected into the inside of the resin case 10 and hardened, so that the entire printed circuit board 11 has a moisture-proof structure, and the elements 3a and 3b and the cable 4 are fixed.
[0025]
As described above, the printed circuit board is fixed in a container-shaped resin case, and the coating material is injected and cured to have a moisture-proof structure. It is possible to solve the problem that it is difficult to control the thickness and the position of the coating without requiring any management.
[0026]
【The invention's effect】
As is apparent from the above description, the antenna for wireless communication of the present invention has the following effects.
[0027]
By configuring and fixing the resin case so as to cover the printed circuit board, especially the balun circuit part in close proximity, the part that directly touches at the time of work etc. is reduced, and stress, dust and dirt adhesion Changes in characteristics can be prevented.
[0028]
In addition, the degree of the effect of the dielectric constant of the resin adjacent to the balun circuit portion is greater, and the resin case is much closer to the resin than the housing housing the wireless communication antenna. For this reason, if the characteristics are set in advance including the effect of the dielectric constant of the resin case and the housing case, the effect of the dielectric constant due to the variation in the distance from the housing can be reduced, and the variation in antenna performance can be reduced. Restrictions on the mounting position of the wireless communication antenna can be reduced, and proper arrangement and downsizing of the housing can be realized.
[0029]
In addition, the printed circuit board is provided with an insertion hole or a notch, the opposed resin case is provided with a fixing claw, and is configured to be inserted and locked on the printed circuit board. It can be realized without increasing the number of man-hours and man-hours, and can prevent cost increase.
[0030]
In addition, the resin case is provided with a concave portion for fixing the element for radio wave transmission between the printed circuit board and the printed circuit board, and the resin case is fitted and fixed to the printed circuit board so that the element is fixed at the same time as the work. Disconnection of the soldered portion of the element due to stress at the time and the like can be prevented, and cost increase due to addition of components for fixing and increase in man-hour can be prevented.
[0031]
Also, by providing a concave portion for fixing the cable to the resin case in the same manner as described above, the cable is fixed at the same time as being fitted and fixed to the printed circuit board, so that the soldering of the cable due to the tensile stress at the time of work etc. Breakage of portions with low mechanical strength such as attachment portions and core portions can be prevented, and costs can be prevented from increasing due to additional components for fixing and an increase in man-hours.
[0032]
In addition, the resin case is formed in a container shape so as to wrap the printed circuit board, and with the printed circuit board fixed, a coating material is injected and cured inside the resin case to make the necessary parts of the printed circuit board a moisture-proof structure, and at the same time, the element In addition, since the cable is fixed, the accuracy of the application position and thickness of the moisture-proof coating can be improved, and the overflow or dripping of the coating material can be prevented, so that the work management until curing can be facilitated. Further, since the element and the cable are also fixed by the coating, it is possible to prevent an increase in cost due to additional parts for fixing and an increase in man-hours.
[Brief description of the drawings]
FIG. 1 is a partially exploded perspective view of a wireless communication antenna according to a first embodiment of the present invention; FIG. 2 is a perspective view after assembly of the antenna is completed; FIG. 3 is a perspective view of a wireless communication antenna according to a second embodiment of the present invention; FIG. 4 is a perspective view showing an example of a conventional wireless communication antenna.
DESCRIPTION OF SYMBOLS 1, 11 Printed circuit board 2 Balun circuit part 3 Element 4 Cable 5, 10 Resin case 6 Claw part 7 Cutout part of printed circuit board 8 Element concave part 9 Cable concave part 12, 13 Notch part 14 of resin case 14 High viscosity Coating material 15 Moisture-proof coating material

Claims (5)

An element for radio wave transmission, a printed board on which this element is mounted, and a balun circuit for matching with a wireless device is formed; a cable connected to the printed circuit board and connected to the wireless device; A wireless communication antenna, comprising: a balun circuit portion; and a resin case that covers the cable, wherein the resin case is positioned and fixed to the printed circuit board. 2. The wireless communication antenna according to claim 1, wherein the printed circuit board has an insertion hole or a notch, and the resin case has a fixing claw that engages with the insertion hole or the notch. 3. The wireless communication antenna according to claim 1, wherein a concave portion for fixing the element is provided in the resin case. 4. The wireless communication antenna according to claim 1, wherein a concave portion for fixing the cable is provided in the resin case. 2. The wireless communication antenna according to claim 1, wherein a resin case is formed so as to surround the printed board, and a coating material is injected into the inside and cured while being fixed to the printed board.

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