JP3230951B2 - Antenna switching structure - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an antenna switching structure in electric equipment, for example, a radio, a portable telephone, and the like.

[0002]

2. Description of the Related Art In a radio device or the like, when only a built-in antenna is provided, a certain level of reception sensitivity can be obtained, but gain, directivity and impedance may not be sufficient. For this reason, the wireless device may be provided with an antenna (retractable antenna) that can be extended and retracted from the housing. Thus, by setting both the external antenna pulled out from the housing and the built-in antenna into the use state, it is possible to maintain the reception sensitivity at a certain level or higher.

[0003] This type of retractable antenna has an antenna switching structure that is used when pulled out of a housing. That is, as shown in FIGS.
A cylindrical insert 3 having both ends opened is attached to the housing 1. The power supply terminal 5 is attached to the insert 3, and the power supply terminal 5 is connected to the duplexer 7. The helical antenna 11 of the retractable antenna 9 is screwed into the insert 3. The helical antenna part 11 has an element part 1 that can be pulled out through the center.
3 are provided. A helical power supply unit 15 is provided at a lower end of the helical antenna unit 11, and the helical power supply unit 15 is connected to the power supply terminal 5. An element feeder 17 is provided at the tip of the element 13.

In the switching structure configured as described above, the element 13 is normally housed and only the helical power supply 15 is connected to the duplexer 7 as shown in FIG. On the other hand, when it is desired to obtain reception sensitivity equal to or higher than a certain level depending on the use state of the antenna, the element portion 13 of the retractable antenna 9 is pulled out. As a result, the element power supply unit 17 comes into contact with the helical power supply unit 15, and not only the helical antenna unit 11 but also the element unit 13 functions as an external antenna.

[0005]

However, in the conventional switching structure, since the retractable antenna 9 is supported and fixed by the insert 3, the element portion is caused by the inclination of the insert 3 or the fitting error of the drawer portion. 13 may be inclined inside the housing, and interference with other components may cause a malfunction of expansion and contraction of the element portion 13 and a malfunction of other components. In addition, a space for accommodating the element unit 13 must be provided in the housing 1, which has been an obstacle in realizing miniaturization of the entire apparatus. Further, in the conventional antenna switching structure, the element feeder 1
7 and the helical power supply unit 15 rub against each other, so that if the number of times of switching is increased, the metal powder may fall into the housing 1 and adversely affect other components on the board. The present invention has been made in view of the above circumstances, and does not interfere with other components in the housing, and has no obstacle to miniaturization, and furthermore, the metal powder generated in the switching contact portion causes the other components to be in contact with other components. An object of the present invention is to provide an antenna switching structure capable of preventing the influence, to achieve reliability of the antenna switching operation, to reduce the size of the device, and to prevent the antenna switching structure from adversely affecting other components.

[0006]

According to another aspect of the present invention, there is provided an antenna switching structure including a shaft made of a conductive material that protrudes from a housing and is fixedly connected to a duplexer provided inside the housing. An external antenna that is rotatably fitted to the shaft and is in a use state when rotated by a predetermined rotation angle from a storage position, and is provided in the external antenna and is electrically connected to a power supply unit of the external antenna, and is always connected to the shaft. A ball bearing made of a conductive material that is urged into contact with the outer peripheral surface of the shaft, and an insulating portion provided on the outer peripheral surface of the shaft and configured to cut off conduction between the ball bearing and the shaft at a position where the external antenna is housed. It is characterized by having.

[0007]

When the external antenna is in the storage position, the ball bearing is insulated by the insulating portion, and the conduction between the external antenna and the shaft is cut off. When the external antenna is turned around the shaft, the ball bearing moves on the outer periphery of the shaft and comes into contact with the outer peripheral surface of the shaft that is not covered with the insulating portion. With this, when the external antenna is stored, only the internal antenna is connected to the duplexer, whereas the external antenna contacts the metal part of the shaft via the ball bearing, is connected to the duplexer via the shaft, and Switching to the simultaneous use state with the external antenna is completed.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of an antenna switching structure according to the present invention will be described below in detail with reference to the drawings. FIG. 1 is a perspective view of the inside of the antenna switching structure of the present invention, and FIG.
1 is an AA sectional view of FIG. 1, FIG. 3 is a BB sectional view of FIG. 1, FIG. 4 is an exploded perspective view of the antenna switching structure of the present invention, and FIG. FIG. 6 is an explanatory view showing a state when an antenna is used in the switching structure of the present invention. A step 23 (FIG. 4)
) Is formed, and a cylindrical shaft 25 is provided on the step portion 23.
Are protruding. An external antenna 27 is rotatably attached to the shaft 25, and the external antenna 27 is stored in a state where the external antenna 27 is tilted to the step portion 23.

That is, the external antenna 27 is connected to the shaft 25.
Is raised from the step 23 around the
It will be used in a state protruding from the device. Further, an internal antenna 29 is provided in the housing 21, and the internal antenna 29 is a duplexer 31 on a substrate provided in the housing.
It is connected to the.

By the way, on the outer surface of the shaft 25, FIG.
As shown in FIG. 5, a pair of concave grooves 33a and 33b formed in the central axis direction and having a semicircular cross section are formed. The shaft 25 is made of a conductive metal, is fixed to the housing 21, and has a metal part connected to the duplexer 31 by wiring. An insulating portion 35 including one concave groove 33a is formed on a part of the outer peripheral surface of the shaft 25.

The external antenna 27 is rotatably mounted by fitting a shaft hole 37 (see FIG. 4) formed at one end into the shaft 25. A cylindrical insert 39 made of a conductive material is provided in the vicinity of the shaft hole 37 of the external antenna 27. The shaft hole 37 and the insert 39 are arranged in a positional relationship where the central axis is orthogonal. A sheet metal member 41 is fixedly provided on the shaft hole 37 side of the insert 39, and the external antenna 2 is provided in the sheet metal member 41.
The helical antenna 43 inside 7 is connected.

In the insert 39, a ball bearing 45 made of a conductive material is inserted. A screw 4 serving as a closing member is provided on a portion of the insert 39 opposite to the sheet metal member 41.
7 is screwed, and a spring 49 is provided between the screw 47 and the ball bearing 45. A ball bearing projection hole 51 is formed in the sheet metal member 41, and a part of the ball bearing 45 urged by a spring 49 projects from the ball bearing projection hole 51. That is, the protruding ball bearing 45
Is projected into the shaft hole 37.

In the antenna switching structure configured as described above, as shown in FIG.
Is disposed by the urging force of the spring 49 in the concave groove 33a on the side where the insulating portion 35 is formed. Therefore, the helical antenna unit 43 includes the sheet metal member 41, the insert 39,
The conduction up to the ball bearing 45 is established, but the conduction with the shaft 25 is interrupted by the insulating portion 35.

In this state, as shown in FIG. 6, when the external antenna 27 is brought into a use state around the shaft 25, the ball bearing 45 moves on the outer periphery of the shaft 25 and is covered by the insulating portion 35. It is arranged in the concave groove part 33b. Thereby, the ball bearing 45 is electrically connected to the metal part of the shaft 25. At this time, the ball bearing 45 falls into the groove 33b,
There is a sense of moderation that regulates the turning power with a certain resistance, and it is clarified that the raising of the external antenna 27 has been completed.

That is, when the external antenna 27 is housed, only the internal antenna 29 is connected to the duplexer 31, but when the external antenna 27 is raised, the ball bearing 45 contacts the metal part of the shaft 25, The helical antenna 43 of the external antenna 27
Sheet metal member 41, insert 39, ball bearing 4
5. It will be connected to the duplexer 31 via the shaft 25. Thereby, the switching to the simultaneous use state of the internal antenna 29 and the external antenna 27 is completed.

According to the above-described antenna switching structure, since the external antenna 27 is provided outside the housing 21, it is possible to eliminate a malfunction in antenna switching caused by interference with other components inside the housing 21. Since it is not necessary to provide a space for housing the external antenna 27 in the housing 21, the size of the apparatus main body can be reduced. Further, unlike the retractable antenna described in the related art, the contact portion is not rubbed every time the drawer is pulled out, and since the contact is provided outside the housing 21, metal powder is generated due to the rubbing of the contact. Therefore, the effect of the metal powder on other components can be completely eliminated. Further, since the antenna switching structure can be configured using the shaft 25 that rotatably supports the external antenna 27 without attaching another switching switch component, the number of components is not increased, and the size and weight are reduced. Can be achieved.

[0017]

As described above in detail, according to the antenna switching structure of the present invention, since the external antenna is provided outside the housing, the antenna switching operation by interfering with other components inside the housing is performed. There is no failure and the reliability of the switching operation can be improved. Further, since there is no need to provide a space for housing the external antenna in the housing, the size of the apparatus main body can be reduced. Furthermore, unlike the retractable antenna, the contact portion does not rub each time it is pulled out, and since the contact is provided outside the housing, no metal powder is generated due to the rubbing of the contact, preventing adverse effects on other parts can do.

[Brief description of the drawings]

FIG. 1 is a perspective view of the inside of an antenna switching structure of the present invention.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is a sectional view taken along line BB of FIG. 1;

FIG. 4 is an exploded perspective view of the antenna switching structure of the present invention.

FIG. 5 is an enlarged view of a main part of the antenna switching structure of the present invention.

FIG. 6 is an explanatory diagram showing a state when an antenna is used in the switching structure of the present invention.

FIG. 7 is an exploded view of a conventional antenna switching structure.

FIG. 8 is an explanatory diagram of a conventional antenna switching structure when the element portion is housed.

FIG. 9 is an explanatory view of a conventional antenna switching structure when the element portion is pulled out.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 21 Housing 25 Shaft 27 External antenna 31 Duplexer 33a, 33b Groove part 35 Insulation part 39 Insert 41 Sheet metal member 45 Ball bearing 47 Screw (closing member) 49 Spring 51 Hole

Continued on the front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) H01Q 1/24 H01Q 1/12 H01Q 1/44 H01Q 21/28

Claims (3)

(57) [Claims] 1. A shaft made of a conductive material protruding from a housing and fixedly connected to a duplexer provided inside the housing, and is rotatably fitted to the shaft and rotated by a predetermined rotation angle from a storage position. An external antenna which is used when the external antenna is in use, a ball bearing made of a conductive material which is provided in the external antenna, which is electrically connected to a feeder of the external antenna, and which is always urged and brought into contact with the outer peripheral surface of the shaft; An antenna switching structure, comprising: an insulating portion provided on an outer peripheral surface of the external member to interrupt conduction between the ball bearing and the shaft when the external antenna is in a housed state. 2. A concave groove formed in the insulating portion to fit a part of the ball bearing when the external antenna is housed, and a part of the ball bearing formed on an outer peripheral surface of the shaft when the external antenna is in use. The antenna switching structure according to claim 1, further comprising a concave groove to be fitted. 3. A cylindrical insert provided in the external antenna and made of a conductive material for accommodating the ball bearing, a sheet metal member having a hole for closing one end of the insert and projecting a part of the ball bearing, and A closing member for closing the other end of the insert, and a part disposed between the closing member and the ball bearing for urging a part of the ball bearing so as to project from the hole; The antenna switching structure according to claim 1, further comprising a spring that contacts an outer periphery of the shaft.