JP2014025795A - Lifting device with automatic antenna elevation angle adjustment mechanism - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a lifting device with an automatic antenna elevation angle adjustment mechanism which automatically adjusts elevation angle of a measurement antenna such that the measurement antenna is always directed toward an object under measurement while moving the measurement antenna up and down so as to enable more accurate measurement of unwanted radiation.SOLUTION: A lifting device with an automatic antenna elevation angle adjustment mechanism of the present invention includes; a lifting pole erected on a top face of a base; a lifting member movably provided to allow vertical movement along the lifting pole; an elevation angle adjustment unit attached to the lifting member; drive means for moving the lifting member up and down; and an inclined cam with one end secured to the lifting pole. A cam rod of the elevation angle adjustment unit is engaged with the inclined cam, and a measurement antenna is mounted on a front rod of the elevation angle adjustment unit.

Description

  The present invention relates to an antenna elevation automatic adjustment lifting apparatus used for measurement of unnecessary radiation of electromagnetic waves generated from electronic equipment.

  In recent years, unnecessary radiation of electromagnetic waves generated from electronic devices and the like has an effect on other electronic devices and the like, which causes a malfunction of these electronic devices and the like. For this reason, measurement and evaluation of unwanted radiation is obligatory and the legal system is in place.

  Usually, measurement and evaluation of unnecessary radiation of electromagnetic waves generated from electronic equipment is performed in accordance with a standard established by the International Commission on Radio Interference (common name: CISPR). According to this standard, the maximum level of unwanted radiation emitted from electronic equipment Must be used to evaluate the effects of electromagnetic interference.

  In order to know the maximum level of this unwanted radiation, measurement must be continued continuously while the distance between the object to be measured and the antenna is 3 m to 10 m and the height of the antenna is 1 m to 4 m. Don't be. During this measurement, the measurement antenna is required to always face the object to be measured. In particular, in the measurement of a high frequency band of 1 GHz or more, a horn-shaped measurement antenna having extremely strong directivity is used, and therefore the measurement antenna needs to be directed to the object to be measured as accurately as possible.

  As antenna lifting devices used for measurement and evaluation of such unwanted radiation of electromagnetic waves, for example, techniques such as Patent Document 1 and Patent Document 2 are known.

JP 2006-177894 A No. 5-45981

  However, in such conventional antenna elevating devices, since the elevating operation of the measurement antenna and the elevation angle providing operation of the measurement antenna are not linked, when the measurement antenna is raised or lowered, it always faces the object to be measured of the measurement antenna. It was difficult to save.

  Therefore, the present invention has been made in view of the above circumstances, and when raising and lowering the measurement antenna, the elevation angle of the measurement antenna is automatically adjusted so that the measurement antenna always faces the object to be measured. As a result, an object of the present invention is to provide an antenna elevation automatic adjustment lifting apparatus capable of measuring unnecessary radiation with higher accuracy.

  In order to achieve the above object, an antenna elevation automatic adjustment lifting apparatus according to the present invention includes a lifting column that is erected on the upper surface of a base, a lifting member that is vertically movable along the lifting column, The elevation angle adjusting unit, which is attached to the elevating member and has at least a front rod and a rear rod, drive means for elevating the elevating member, and an inclined cam fixed at one end to the elevating support column, and the elevation angle The rear rod of the adjustment unit is engaged with the inclined cam, and a measurement antenna is attached to the front rod of the elevation adjustment unit.

  According to the present invention, since the rear rod of the elevation adjustment unit is engaged with the inclined cam as the elevation member moves up and down, the elevation angle of the measurement antenna is automatically adjusted in conjunction with the elevation of the elevation adjustment unit. It is possible to measure unnecessary radiation with higher accuracy.

  Furthermore, in the antenna elevation angle automatic adjustment lifting apparatus of the present invention, it is preferable to provide a tilt angle adjustment support rod between the other end of the tilt cam and the lower part of the lifting column. By adopting such a configuration, the stability of the tilt cam is improved, the adjustment accuracy of the elevation angle is further improved, and more accurate measurement of unnecessary radiation becomes possible.

  Furthermore, the antenna elevation angle automatic adjustment lifting apparatus of the present invention preferably includes a length adjustment mechanism on the inclination angle adjustment support rod. By adopting such a configuration, it is possible to set an appropriate angle of the tilt cam by adjusting the length of the tilt angle adjusting support bar in advance according to the measurement distance. As a result, it is possible to accurately measure unwanted radiation and to shorten the set time.

  In the antenna elevation automatic adjustment lifting / lowering apparatus of the present invention, it is preferable that a radio wave absorber is attached to the tilt cam and the tilt angle adjustment support rod. By adopting such a configuration, it is possible to suppress reflection of unnecessary radiation emitted from the object to be measured, and to perform measurement with higher accuracy.

  According to the present invention, it is possible to automatically adjust the elevation angle of the measurement antenna so that the measurement antenna always faces the object to be measured, and as a result, the antenna elevation angle automatic capable of measuring unnecessary radiation with higher accuracy. An adjustment lifting device can be provided.

It is a perspective view which shows the antenna elevation angle automatic adjustment raising / lowering apparatus by this embodiment. It is the figure which looked at the raising / lowering support | pillar of the antenna elevation angle automatic adjustment raising / lowering apparatus by this embodiment from the inclination cam side. (A) is a side view when the elevation angle adjustment unit in this embodiment becomes a rectangle. (B) is a side view when the elevation adjustment unit in the present embodiment is a parallelogram. It is a front view of the inclination angle adjustment stick | rod in this embodiment. It is a front view of the inclination-angle adjustment stick | rod of this embodiment. It is the figure which attached the electromagnetic wave absorber to the inclination cam and inclination angle adjustment rod of this embodiment.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a perspective view showing a configuration of an antenna elevation automatic adjustment lifting apparatus 1 according to the present embodiment.

  An antenna elevation automatic adjustment lifting apparatus 1 according to the present embodiment includes a lifting column 3 standing on an upper surface of a base 2, a lifting member 4 provided so as to move up and down along the lifting column 3, and a lifting member 4. And a drive means 7 and a drive unit 8 for raising and lowering the elevating member 4, and an inclined cam 9 having one end fixed to the elevating support column 3, and a rear rod 10 of the elevation angle adjusting unit 6. The measuring antenna 12 is attached to the front rod 11 of the elevation adjustment unit 6 via the antenna fixing holder 32.

  The base 2 includes a base member 13 and a sub base member 14. When these members are made of a non-metallic material such as fiber reinforced plastic or vinyl chloride, it is possible to suppress reflection of electromagnetic waves radiated from the object 15 to be measured. Reflection can be reduced.

  The base member 13 may be made of a plate formed in a rectangular shape, and casters 16 may be provided at the four corners on the back surface of the base member 13 so that the antenna elevation angle automatic adjustment lifting apparatus 1 can be moved. In the vicinity of the caster 16, an adjuster foot 17 for adjusting the height may be provided in a screw hole provided so as to penetrate the base member 13 in the vertical direction. Stable evaluation can be performed by adjusting the height of the adjuster foot 17.

  A rectangular sub-base member 14 is provided on the upper surface of the base member 13, and the sub-base member 14 is fixed to the base member 13 by a fixing screw 18 through a plurality of through holes provided on the peripheral side. . On the sub-base member 14, the lifting column 3, the driving unit 8, and the driving unit 7 are installed.

  The lifting column 3 is made of a non-metallic material such as fiber reinforced plastic so that the lifting member 4 to which the elevation angle adjusting unit 6 is fixed can be moved up and down and the reflection of electromagnetic waves is suppressed. In addition, a reinforcing member 19 is provided at the lower end portion of the lifting column 3 to expand its installation area and ensure installation stability, and is fixed on the sub-base member 14.

  The elevating member 4 includes a holding portion lid 23, a slider 5, and a holding portion 21, and the antenna stay 22 of the elevation angle adjusting unit 6 is fixed to the holding portion 21. The holding portion 21 has a U-shaped shape, and an antenna stay 22 is fitted into the U-shaped portion, and a holding portion lid 23 is fixed from above with a screw or the like. The antenna stay 22 can be finely adjusted in a direction toward and away from the object to be measured 15.

  The elevation operation of the elevation adjustment unit 6 will be described with reference to FIGS. The drive unit 8 is provided with a motor, and a drive gear is provided as the drive means 7. When the motor rotates, the drive gear provided at the end of the rotation shaft rotates, and the timing belt 33 wound between the drive pulley and the timing pulley 34 provided at the upper part of the lifting column 3 also circulates. The inner surface of the timing belt 33 has a groove shape and engages with a protrusion provided on the outer periphery of the drive gear or the timing pulley 34.

  As shown in FIG. 2, the elevating member 4 is fixed to the belt on the left side of the timing belt 33 by a belt holder 36 as shown in FIG. 2. Therefore, when the timing belt 33 rotates to the left toward FIG. 2, the elevating member 4 rises, and when the timing belt 33 rotates to the right toward FIG. 2, the elevating member 4 descends.

  As shown in FIG. 3A, the elevation adjustment unit 6 has a rectangular shape, the antenna stay 22 and the substay 24 form a long side, and the front rod 11 and the rear rod 10 form a short side. The antenna stay 22 and the substay 24 constituting the elevation angle adjusting unit 6 are connected to the front rod 11 via a pre-stay hinge 25 and connected to the rear rod 10 via a post-stay hinge 26. By rotating the pre-stay hinge 25 and the post-stay hinge 26, the elevation angle adjusting unit 6 can freely change the shape from a rectangle to a parallelogram as shown in FIG. A lever 27 formed continuously with the rear rod 10 is bent toward the inclined cam side to form a cam rod 28 that engages with the inclined line hole 29. The end portion of the cam rod 28 can slide the inclined line hole 29 in accordance with the lifting / lowering operation of the lifting / lowering member 4.

  The operation in the measurement evaluation of the antenna elevation automatic adjustment lifting apparatus 1 configured as described above will be described.

  As described above, in measurement of unwanted radiation, the measurement object 15 is placed on a table having a height of about 80 cm, and the measurement antenna 12 is fixed at a position separated from the measurement object 15 by about 3 m to 10 m. Then, the measurement antenna 12 is moved up and down in the range from 1 m to 4 m in height, and the measurement evaluation operation when the distance between the measurement antenna 12 and the DUT 15 is 10 m will be described below.

  First, the position of the tilt cam 9 is adjusted in consideration of the measurement distance between the measurement antenna 12 and the DUT 15. The closer the distance between the measurement antenna 12 and the object 15 to be measured, the larger the angle formed between the lifting column 3 and the inclined cam 9. Conversely, the farther the distance between the measurement antenna 12 and the object 15 to be measured, The angle formed by the lifting column 3 and the inclined cam 9 is reduced. When the measurement distance is 10 m, the angle is about 3 degrees. This angle can be easily changed by adjusting the joint hinge portion 30 provided on the inclined cam adapter 31 that supports the inclined cam 9.

  Next, the antenna stay 22 is slid and fixed. For example, when the total length of the front rod 11 and the rear rod 10 is about 50 cm, when the distance between the measurement antenna 12 and the object 15 to be measured is 10 m, the antenna stay 22 is slid to the tilt cam 9 side by about 13 cm. become. Similarly, when the measurement distance is 1 m, the distance is 50 cm, and when the measurement distance is 3 m, the distance is 33 cm. As the distance between the measurement antenna 12 and the measurement object 15 increases, the ratio of sliding the antenna stay 22 toward the inclined cam 9 decreases.

  As described above, after the antenna stay 22 is moved back and forth in accordance with the measurement distance and the measurement antenna 12 is positioned, the elevating member 4 is set so that the center of the position of the measurement antenna 12 becomes a height of 1 m as a measurement evaluation start point. Is moved along the lifting column 3. At this time, the substay 24 is prevented from contacting the reinforcing member 19. At this position, the elevation adjustment unit 6 is rectangular.

  When the measurement evaluation is started, the motor of the driving unit 8 rotates, and the driving gear serving as the driving unit 7 rotates the timing belt 33 in the left direction. As a result, the elevation angle adjustment unit 6 fixed to the elevating member 4 rises at a constant speed together with the measurement antenna 12 attached to the front rod 11 via the antenna fixing holder 32. At this time, since the cam rod 28 is engaged with the inclined line hole 29 of the inclined cam 9, the cam rod 28 also rises along the inclined line hole 29 as the elevating member 4 rises. Along with this movement, the rear rod 10 is interlocked with the front rod 11 with the post-stay hinge 26 as a fulcrum, and the elevation angle adjusting unit 6 rises slowly changing its shape. Since the cam rod 28 rises along the inclination of the inclined cam 9, the cam rod 28 approaches the lifting column 3 as the position thereof becomes higher.

  That is, as shown in FIG. 3A, before the measurement is started, the shape of the rectangular elevation adjustment unit 6 including the front rod 11, the rear rod 10, the antenna stay 22, and the sub stay 24 is changed to the shape shown in FIG. As shown to b), it becomes a parallelogram gradually with the raising / lowering member 4 ascending.

  Due to this shape change, the front rod 11 forming one side of the parallelogram also tilts simultaneously with the rear rod 10 with respect to the tilt cam 9 with the hinge portion 25 before stay as a fulcrum. Thus, the measurement antenna 12 fixed to the front rod 11 faces the measurement object 15 as the elevating member 4 moves up.

  In this embodiment, one end of the inclined cam 9 is supported in a cantilevered manner on the upper part of the lifting column 3, but it may be further fixed to the lower end side of the lifting column 3 using an inclination angle adjusting rod 37. If it does so, the inclination cam 9 will be fixed more firmly, and the cam rod 28 will be able to slide the inclination line hole 29 more stably.

  Further, as shown in FIG. 4, the tilt angle adjusting rod 37 has a length adjusting function, and an appropriate angle of the tilt cam 9 corresponding to the distance between the measurement antenna 12 and the measured object 15 is calculated in advance. The scale 20 may be engraved on the tilt angle adjusting rod 37 so that this angle can be set immediately for each measurement distance.

  Since the tilt cam 9 and the tilt angle adjusting rod 37 are located on a straight line connecting the device under test 15 and the measurement antenna 12, unnecessary radiation emitted from the device under test 15 is easily reflected in the direction of the measurement antenna 12. Therefore, it is desirable to attach a radio wave absorber 38 made of a magnetic material or the like to the tilt cam 9 or the tilt angle adjusting rod 37 as shown in FIG. As a result, unnecessary radiation emitted from the DUT 15 is absorbed by the radio wave absorber 38, and reflection in the direction of the measurement antenna 12 is suppressed as much as possible to obtain a more accurate measurement result.

  In this way, measurement and evaluation of unnecessary radiation is continuously performed until the ground height of the measurement antenna reaches 1 m to 4 m. However, according to the antenna elevation automatic adjustment device of this embodiment, measurement is performed when the measurement antenna is raised and lowered. To provide an antenna elevation automatic adjustment lifting device capable of automatically adjusting the elevation angle of a measurement antenna so that the antenna always faces the object to be measured and, as a result, capable of measuring unnecessary radiation with higher accuracy. Can do.

DESCRIPTION OF SYMBOLS 1 Antenna elevation angle automatic adjustment raising / lowering device 2 Base 3 Elevating support column 4 Elevating member 5 Slider 6 Elevation angle adjusting unit 7 Driving means 8 Driving portion 9 Inclining cam 10 Rear rod 11 Front rod 12 Measuring antenna 13 Base member 14 Sub base member 15 Cover Measurement object 16 Caster 17 Adjuster foot 18 Fixing screw 19 Reinforcement member 20 Scale 21 Holding part 22 Antenna stay 23 Holding part lid 24 Sub stay 25 Hinge before stay 26 Hinge after stay 27 Lever 28 Cam rod 29 Inclined line hole 30 Joining hinge part 31 Inclined cam Adapter 32 Antenna fixing holder 33 Timing belt 34 Timing pulley 35 Upper belt holder 36 Belt holder 37 Inclination angle adjusting rod 38 Wave absorber

Claims (4)

  Elevating angle adjusting unit having an elevating support column erected on the upper surface of the base, an elevating member provided to be movable up and down along the elevating support column, and at least a front rod and a rear rod attached to the elevating member Driving means for raising and lowering the elevating member, and an inclined cam fixed at one end to the elevating support column, and the rear rod of the elevation angle adjusting unit is engaged with the inclined cam, and the elevation angle adjusting unit An antenna elevation automatic adjustment lifting apparatus, characterized in that a measurement antenna is attached to the front rod.   2. The antenna elevation angle automatic adjustment lifting apparatus according to claim 1, wherein a tilt angle adjustment support rod is provided between the other end of the tilt cam and a lower portion of the lifting column.   The antenna elevation angle automatic adjustment lifting apparatus according to claim 2, wherein the tilt angle adjustment support bar includes a length adjustment mechanism.   4. The antenna elevation automatic adjustment lifting apparatus according to claim 1, wherein a radio wave absorber is attached to the tilt cam and the tilt angle adjustment support rod. 5.

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