JPH04336802A - Manufacture of whip antenna - Google Patents

Abstract

PURPOSE:To reduce the entire processing time and to allow the method to easily cope with various shapes in the case of manufacturing a whip antenna by the swaging method. CONSTITUTION:A stroke of a head for knocking a high tensile strength material is changed during one working by the swaging method in the method for manufacturing the whip antenna in which the high tensile strength material is worked by the swaging method wile the high tensile strength rod material is moved in the axial direction.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a whip antenna.

0002

[Prior Art] Antennas with various structures are used as car radio antennas, but among them, a single-length whip antenna is an antenna that maintains the required minimum reception function and pursues low cost. It has been known.

[0003] The receiving section of this single-length whip antenna is
A single rod-shaped conductive member (
After being attached to the vehicle body, it remains exposed outside the vehicle body. Therefore, the above-mentioned whip antenna is made of a high tensile strength material with high resilience so that it can sufficiently withstand the load caused by obstacles while the vehicle is running, the load applied during car washing, parking in a garage, etc. Furthermore, in order to reduce wind noise, some of these antennas use multi-stage antennas that have a straight part whose diameter gradually decreases as it approaches the tip of the antenna.

[0004] As an antenna of this kind,
There is an antenna described in Japanese Patent No. 11305, which is formed by hammering and forging work.

[0005]

Problems to be Solved by the Invention The following methods can be considered for manufacturing the above-mentioned conventional multi-stage whip antenna by a conventional method. First, the rod-shaped material is moved at a constant speed in the axial direction from the antenna base toward the tip, and the head hits the material from the radial direction to perform the first swaging process. conduct. In this case, processing is performed with a constant stroke of the head, that is, processing is performed to a diameter that is slightly smaller than the diameter of the material and is the same. Then, a second process is performed from a position a predetermined distance away from the base of the antenna toward the tip of the antenna, and at this time, the stroke of the head is slightly lengthened (the diameter is slightly shortened). . In this case as well, swaging is performed while moving the material at the same processing speed as above. Hereafter, gradually shorten the machining distance to the tip of the antenna and perform the swaging process as many times as necessary, such as the third and fourth times, and lengthen the stroke of the head as the number of swaging processes increases. . By processing in this way, a multi-tiered whip antenna can be manufactured.

However, when machining is performed in this way, there is loss time between one machining and the next, such as between the first and second machining, so the overall There is a problem that processing time becomes long.

Furthermore, according to the above method, the stroke of the head is constant in one swaging process, so although it is possible to process a multi-step shape, it is difficult to process the cross section with a curve. It is extremely difficult and practically impossible to process the cross section with a uniform taper, or to form a protrusion in the radial direction between the base and tip of the antenna. There is a problem.

[0008] The present invention provides a method for manufacturing a whip antenna, which can shorten the entire processing time when manufacturing a whip antenna by a swaging method, and can easily accommodate various shapes. The purpose is to provide the following.

[0009]

[Means for Solving the Problems] The present invention provides a method for manufacturing a whip antenna by processing a rod-shaped high tensile strength material by a swaging method while moving the high tensile strength material in its axial direction. The aging method changes the stroke of the head that strikes the high tensile strength material during processing.

0010

Embodiment FIG. 1 is an explanatory diagram of an embodiment of the present invention.

In this embodiment, the workpiece W is a rod-shaped high tensile strength material, and one end of the workpiece W is held between the chucks C, and the workpiece W is gradually moved to the left in the figure (leftward on the Y axis) with respect to the heads H1 and H2. The heads H1 and H2 move up and down at a preset constant speed, thereby striking the surface of the workpiece W and processing it by a swaging method. That is, when head H1 moves upward on the X-axis in the figure, head H2 moves downward on the X-axis, and heads H1 and H2
The workpieces W are struck at the same time. At the same time, the heads H1 and H2 rotate at high speed in the circumferential direction of the workpiece W, the chuck C also rotates in the circumferential direction of the workpiece W, and as the chuck C rotates, the workpiece W also rotates and swags. Processing is performed. Actually, the work W
The rotational speed of the heads H1 and H2 is much faster than the rotational speed of the heads H1 and H2.

The strokes of the heads H1 and H2 can be changed, and the strokes of the head H1 and H2 are always set to be the same. Further, it is set such that the larger the strokes of the heads H1 and H2, the slower the speed at which the chuck C moves the workpiece W in the axial direction.

In reality, the strokes of the heads H1 and H2 and the moving speed of the chuck C are set by the operator in advance, and based on the set values, a CNC (computer numerical control) device adjusts the strokes and the moving speed of the chuck C. The movement speed is controlled. In this case, the number of strokes per unit time of heads H1 and H2 is set constant.

FIG. 2 is an explanatory diagram when processing the workpiece W into a multistage shape, that is, a shape having a plurality of straight portions having different diameters in the above embodiment.

FIG. 2(1) is a front view of the antenna A1 arranged horizontally. The diameter of this antenna A1 gradually decreases as it approaches from the antenna base B to the antenna tip T, and from the antenna base B to the antenna tip T, regions R11, R12, R13, R14, R15 have different diameters. is formed. FIG. 2(2) is a chart showing various data when processing the antenna A1.

This antenna A1 is processed sequentially from the antenna base B to the antenna tip T.
, 70 mm, 80 mm, 90 mm, and 100 mm, and the diameters thereof are 4.5 mm and 4.0 m, respectively.
m, 3.5 mm, 3.0 mm, and 2.5 mm. Also, the strokes of heads H1 and H2 are α and α+, respectively.
0.25, α+0.5, α+0.75, α+1.0, and so on. In this case, α is a predetermined length. Furthermore, the speed at which the chuck C is moved to the left in the Y-axis direction in FIG.
00mm/min, and the diameter is 4.0mm, 3.5mm,
As the length increases to 3.0 mm and 2.5 mm, the moving speed of the workpiece W becomes 700 mm/min, 600 mm/min, 500 mm/min, and 400 mm/min, respectively.

As described above, in the above embodiment, the strokes of the heads H1 and H2 are changed depending on the position of the antenna A1 in processing by one swaging method. Antenna A1 can be manufactured only by processing, and therefore,
There is no loss time in processing by the swaging method, and the manufacturing time of the antenna A1 can be shortened. Here, "processing using a single swaging method" means:
It means "processing performed by continuously moving the workpiece W from a predetermined part of the antenna to another part", and in "processing by one swaging method", head H1,
With respect to H2, the workpiece W moves only in one direction and does not reciprocate. In actual swaging processing, the chuck C reciprocates with respect to the heads H1 and H2. For example, when the chuck C reciprocates five times, five antennas A1 are manufactured. However, in the past,
The chuck C reciprocates five times with respect to the heads H1 and H2, and finally one antenna A1 is manufactured. or
Conventionally, in order to manufacture one antenna in one reciprocating motion, it is necessary to stop the machine at that position to change the stroke of the heads H1 and H2 each time the diameter of the antenna changes. It is necessary to stop the machine five times to manufacture antenna A1. From this point as well, it can be understood that the manufacturing method of the above embodiment has a high manufacturing speed.

Furthermore, according to the above embodiment, the antenna A1 can be manufactured by only one swaging process, and focusing on a predetermined portion of the antenna A1,
The predetermined portion is swaged only once (processing is performed continuously), and therefore the machining of the predetermined portion is completed while the predetermined portion is hot, so the machining speed is high and the machining time is It has the advantage of being shorter. Also,
Since the machining of the predetermined portion is completed while the predetermined portion is still hot, the load on the heads H1 and H2 is reduced, and the head H
1. There is an advantage that the life of H2 becomes longer.

Furthermore, in the above embodiment, the diameter of the workpiece W can be arbitrarily changed during machining by one swaging method, so there is an advantage that the finished shape can be made into an arbitrary shape. .

FIG. 3 is an explanatory diagram of another antenna shape in the above embodiment, and FIG. 3(1) shows straight parts R21 and R23 whose cross section is parallel to the axis, and straight parts R21 and R23 whose cross section is not parallel to the axis. FIG. 3(2) is an external view of a straight tapered antenna A2 combined with a tapered portion R22 having a section, and FIG. 3(2) is a diagram showing processing conditions when processing the antenna A2 by a swaging method.

When processing the antenna A2, the moving speed of the work W is 400 mm/min in the region R21 whose diameter is 4 mm, and the moving speed of the work W is 400 mm/min in the region R23 whose diameter is 2.5 mm. 300mm/
minutes, and the smaller the diameter of antenna A2 (work W), the slower the moving speed of work W becomes.

Note that the diameter in region R22 is as shown in FIG.
2), the diameter is 4 to 2.5 mm, but in this case, in order to obtain an even taper, the linear interpolation function is used to gradually change the diameter (heads H1, H
2 strokes). This is head H1
, H2, in the region R22, α
~ α + 0.75 mm, but this is because the stroke of this head is gradually changed by a linear interpolation function (the diameter gradually becomes shorter from the antenna base B to the tip T). . In addition, work W
The moving speed is set to 300 mm/min in region R22.

FIGS. 4(1) to 4(4) are front views of other antennas A3, A4, A5, and A6 according to the present invention.

FIG. 4(1) shows an antenna A3 having a straight taper shape, which is a combination of a straight part R31 having a section parallel to the axis and a tapered part R32 having a section not parallel to the axis. FIG. 4(2) is a front view of an antenna A4 having a straight portion R41 and a tower-shaped region R42 whose cross section is curved and whose diameter is smaller as it approaches the antenna tip T. be.

FIG. 4(3) shows straight parts R51, R53, R55 having sections parallel to the axis, and tapered parts R52, R54 having sections non-parallel to the axis.
, R56 is a front view of an antenna A5 having a straight taper shape arranged alternately, and FIG. 4(4)
are the straight part R61 and the tapered parts R62 and R63.
, R64, R65, and R66, and is a front view showing a multi-protrusion antenna A6 having ring-shaped protrusions T1, T2, T3, and T4 between each tapered portion. In other words, the antenna A6 has a plurality of protrusions having ring-shaped protrusions at predetermined intervals.

Also in FIGS. 4(1) to (4), the shorter the diameter of each antenna, the longer the stroke of the heads H1 and H2, and the longer the stroke of the heads H1 and H2, the longer the workpiece W is moved. Machining is performed by slowing down the speed of movement in the axial direction. In this case, heads H1, H2
Machining is performed by slowing down the movement speed in the axial direction relative to the number of strokes per unit time. That is, actually the head H1
The number of strokes per unit time by heads H1 and H2 is set to a fixed value, but if the number of strokes per unit time by heads H1 and H2 is increased, the moving speed in the axial direction can be increased accordingly. good.

In the antenna A6 having a plurality of protrusions shown in FIG. 4(4), the protrusions T1 to T4 have hexagonal front projections;
Protrusions that are rectangular and have a longer length in the lateral direction (in the axial direction of antenna A6) may be used, or protrusions T1 to T4 may be formed in a concentrated manner near the base B of antenna A6. You can do it like this.

Further, constants such as the strokes of the heads H1 and H2 and the moving speed of the workpiece W may use values other than those used in the above embodiment. Further, in the above embodiment, the workpiece W is hit by two heads, but the workpiece W may be hit by three or more heads.

Furthermore, in the above embodiment, the heads H1, H
It is set so that the larger the stroke of head H1, H2, the slower the speed of movement of the workpiece W in the axial direction by the chuck C.
Workpiece W by chuck C regardless of the stroke of
The moving speed in the axial direction may be kept constant.

[0030]

[Effects of the Invention] According to the present invention, when manufacturing a whip antenna by the swaging method, the entire processing time can be shortened, and various shapes can be easily manufactured. play.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram of an embodiment of the present invention.

FIG. 2 is an explanatory diagram of an antenna A1 manufactured according to the above example.

FIG. 3 is an explanatory diagram of an antenna A2 manufactured according to the above example.

FIG. 4 Antenna A3 manufactured according to the above example;
It is a front view of A4, A5, and A6.

[Explanation of symbols]

W...rod-shaped high tensile strength material, C...Chuck, A1 to A6...antenna, H1, H2...Head.

Claims (4)

[Claims] Claim 1. A method for manufacturing a whip antenna by processing a rod-shaped high tensile strength material by a swaging method while moving the rod-shaped high tensile strength material in its axial direction, the method comprising the steps of: A method for manufacturing a whip antenna, comprising changing the stroke of a head that strikes the high tensile strength material. 2. The whip according to claim 1, wherein the larger the stroke of the head, the slower the speed at which the high tensile strength material is moved in its axial direction relative to the number of strokes per unit time. How to manufacture an antenna. 3. The method for manufacturing a whip antenna according to claim 1, wherein the speed at which the high tensile strength material is moved in its axial direction is kept constant with respect to the number of strokes per unit time. 4. In claim 1, the finished shape of the whip antenna is a multi-stage shape having straight portions having different diameters, a straight portion having a portion whose cross section is parallel to the axis line, and a portion having a cross section not parallel to the axis line. A straight taper shape combined with a tapered part, a tower shape with a curved cross section and a diameter smaller as it approaches the tip of the antenna, or a multiple protrusion shape with ring-shaped protrusions at predetermined intervals. The manufacturing method of the featured whip antenna.