1. Technical Field
The disclosure relates to cavity filters, and more particularly relates to a connecting structure between a slider and a driving device in a cavity filter.
2. Description of Related Art
Cavity filters are popularly used in mobile communications. Generally, a cavity filter comprises a shell, a slider, a plurality of resonators, and a motor. The slider is movably connected to the shell and opposite to the plurality of resonators arranged in the shell. The motor drives the slider to move relative to the shell and couples with the resonators to adjust resonating frequency of the cavity filter. Generally, the slider is fixed to the motor by fasteners, such as screws. However, vibration of the motor causes the slider to vibrate, which makes the slider not able to move on an even keel, thereby reducing efficiency of adjusting the resonating frequency of the cavity filter.
Therefore, a need exists in the industry to overcome the described limitations.
Many aspects of the present embodiments can be better understood with reference to the following drawings. The components in the drawings are not necessarily drawn to scale, the emphasis instead being placed upon clearly illustrating the principles of the present embodiments. Moreover, in the drawings, all the views are schematic, and like reference numerals designate corresponding parts throughout the several views.
The disclosure is illustrated by way of example and not by way of limitation in the figures of the accompanying drawings in which like references indicate similar elements. It should be noted that references to “an” or “one” embodiment in this disclosure are not necessarily to the same embodiment, and such references mean at least one.
In
The driving device 40 is fixed in the shell 10 by screws 46 and comprises a shaft 42 parallel to the slider 20. In assembly, the fixing portion 22 is located above the shaft 42. The adapter 50 is installed between the fixing portion 22 and the shaft 42. In this embodiment, the driving device 40 is a step motor, but the disclosure is not limited thereto. When the driving device 40 is powered on, the shaft 42 moves along an axial direction of the shaft 42, thereby the slider 20 move on the plurality of positioning portions 14 and coupling with the resonators 30 to change a resonating frequency of the cavity filter 100. Vibrations of the shaft 42 along a radial direction are created during moving of the shaft 42. The shaft 42 is fixed to the adapter 50. The resilient member 60 is elastically connected between the slider 20 and the adapter 50. When the driving device 40 is powered on, the resilient member 60 absorbs the vibrations of the shaft 42, thereby the slider 20 can move on an even keel on the plurality of positioning portions 14 without vibrations. That is the slider 20 is snugly supported on the plurality of positioning portions 14 constantly during moving. Furthermore, the resilient member 60 is capable of absorbing a positioning error between the shaft 42 and the adapter 50, that is, if the shaft 42 is not be entirely parallel to a substantially horizontal plane due to the positioning error between the shaft 42 and the adapter 50, the slider 20 can still be positioned in the substantially horizontal plane on the plurality of portions 14 due to the resilient member 60 can adjust the situation of the slider 20.
In this embodiment, the fixing portion 22 of the slider 20 defines a through hole 222. The adapter 50 defines a screw hole 52 opposite to the through hole 222. In assembly, the resilient member 60 is clamped between the adapter 50 and the fixing portion 22 of the slider 20, and a screw 70 passes through the through hole 222, the resilient member 60 and is screwed into the screw hole 52, thereby the slider 20 is connected to the adapter 50. The screw 70 engages with the through hole 222 with a clearance fit, that is, the screw 70 is capable of moving in the through hole 222 freely under an external force.
The adapter 50 defines an installing hole 56 opened toward the shaft 42 of the driving device 40, as shown in
The resilient member 60 absorbs the vibrations of the shaft 42 along the radial direction due to elastic potential energy of the resilient member 60. Therefore, the slider 20 can move on an even keel to improve efficiency of adjusting the resonating frequency of the cavity filter 100.
While the exemplary embodiments have been described, it should be understood that it has been presented by way of example only and not by way of limitation. The breadth and scope of the disclosure should not be limited by the described exemplary embodiments, but only in accordance with the following claims and their equivalent.
Number | Date | Country | Kind |
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2012 2 0089237 U | Mar 2012 | CN | national |
Number | Name | Date | Kind |
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8294536 | Wong | Oct 2012 | B2 |
20140292445 | Wong | Oct 2014 | A1 |
Number | Date | Country | |
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20130234807 A1 | Sep 2013 | US |