JPS61276499A - Diaphragm for loudspeaker - Google Patents

Abstract

PURPOSE:To make a roll edge high in renearity to amplitude by specifying the shape of V-shaped grooves formed on the edge of a loudspeaker diaphragm. CONSTITUTION:Many V-shaped grooves 7 are formed on an edge formed by a conical face 5 of semi-apex angle (a) 45 deg. from an inner peripheral circle and a conical face 6 of the same semi-apex angle from an outer peripheral circle. Troughs of the grooves 7a start from circular arcs 7c of radial angle C at angles 20-40 deg.C to a circle 3 and end in circular arcs 7e that become tangent of a circle 4 through straight lines 7d of tangent, and formed by a circular arc of radius R1 between circles 3, 4, and groove walls 7f are formed at an angle of 90 deg. to the troughs 7a. Crests 7b are made to a circular arc face of radius R2 that start from supporting points between the walls 7f and the face 5 and end at intersection with the face 6. Because of this shape, the depth and width of grooves 7 are the same from inner periphery to outer periphery, and the grooves 7 do not overlap on the edge face and become roll form of circular arc shape in vertical direction, and hardness of the edge becomes uniform throughout the whole area. Consequently, a roll edge of a loudspeaker diaphragm high in linearity to amplitude is obtained.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a speaker diaphragm used for sound reproduction, in which a plurality of V-shaped grooves are provided in the edge shape, more specifically, in the roll edge. This invention relates to improvements to diaphragms for speakers.

[Conventional technology]

The conventional roll edge speaker diaphragm of this type is
rM ~ shown in FIG.

In plan view, the V-shaped groove 1 provided on this diaphragm has a valley bottom 1a reaching the outermost circle 2b in a straight line tangential to the innermost circle 2a of the edge, and a peak 1b at the innermost circle. It starts with a straight line in the tangential direction and separates from the middle toward the adjacent valley bottom 1b.

The space between the separated peaks 1b is a circular surface 1c centered on the center of the diaphragm and passing through the separated peaks 1b.

Also, in the vertical direction, as shown in Figure 6, the valley floor 1a is also the mountaintop 1b.
are also the same height in the innermost circumferential circle 2a and the outermost circumferential circle 2b,
The valley bottom 1as and the mountain peak 1b are also curved upward so that the height difference between the mountain peak 1b and the valley bottom 1a is greatest at the part where the mountain peak 1b separates, that is, the highest part of the mountain peak 1b.

In this way, a V-shaped groove is formed from the innermost circumference to the outermost circumference with a straight line in the tangential direction.
The distance to the apex of the peak 1b, that is, the length of the inner groove, and the distance from the apex of the peak 1b to the outermost circumference, that is, the length of the outer groove are not equal (the inner groove is longer).

Further, the groove width is narrow at the innermost circumference and widest at the apex of the peak 1b, and an inner surface IC is formed outside the apex of the peak 1b.

[Problem that the invention seeks to solve]

In the roll edge of conventional speaker diaphragms, as mentioned above, the groove in the inner circumferential direction from the apex of the peak 1b is longer than the outer circumferential direction, and the groove width is narrower, resulting in a +7-shaped shape that is thin and long, and therefore weak. .

On the other hand, the grooves in the outer circumferential direction are short in length and have a large difference in groove width and between the valley bottom 1a and the peak 1b, that is, have a strong shape.

As a result, the edge becomes unbalanced, with the inner circumference being soft and the outer circumference being hard, which has the disadvantage of poor linearity with respect to swing width.

[Purpose of the invention]

The present invention is intended to eliminate the above-mentioned drawbacks of conventional speaker diaphragms, and aims to provide a roll edge speaker diaphragm that has high linearity with respect to amplitude due to the 7-shaped grooves formed on the entire edge surface. purpose.

[Summary of the invention]

In order to achieve the above-mentioned object, the present invention forms the width and depth of the V-shaped groove formed in the roll edge almost unchanged from the innermost circumference to the outermost circumference, and also changes the planar shape of the V-shaped groove. The purpose is to change the

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to FIGS. 1 to 3.

3 is the inner circumferential circle of the edge portion, 4 is the outer circumferential circle, and the conical surface 5 has a half apex angle a of 45 degrees from the inner circumferential circle 3, and the conical surface 5 has a half apex angle of the same angle from the outer circumferential circle 4. 6 is formed.

The bottom 7a of the V-shaped groove 7 formed in this edge part is
Planarly, it starts with an arc 7C with a radiation angle C of 20 to 40 degrees with respect to the inner circle 3, becomes a straight line 7d that is tangent to the arc 7C, and finally becomes a tangent to the outer circle 4. It ends at arc 7e.

The bottom 7a of this V-shaped groove 7 is formed by an arc with a radius R1 starting from the inner circumferential circle 3 and ending at the outer circumferential circle 4.
The groove wall surface 7f is formed at an angle of 90 degrees with respect to the groove.

Therefore, the apex where the groove wall surface 7f and the conical surface 5 intersect is the beginning of the crest 7b of the groove 7, and the apex where the groove wall surface 7f and the conical surface intersect is the end of the crest 7b.

Then, a surface drawn by connecting the vertices with an arc of radius R2 becomes the surface of the mountain top 7b.

The reason why the wall surface 7f intersects with the conical surface 5 and the conical surface 6 is because the width of the stringer 7 is smaller than the distance between the adjacent grooves, they intersect with a line, and the vibrations pass through this line with a curved surface of radius R2. The circumferential surface centered on the plate becomes the surface of the peak 7b.

In this way, for example, %f27 grooves 7 are formed in the edge portion.

8 is an air vent hole drilled in the peak 7b.

Therefore, the figure 7 groove 7 touches the conical surfaces 5 and 6 and the peak 7b
The height from the valley bottom 7a to the peak 7b when the valley is formed, that is, the depth of the groove 7 is the same on both the inner and outer circumferences, so the width is also the same, and the depth when the valley bottom 7a begins. is 0 on both the inner and outer circumferences.

Next, the valley bottom 7a begins with a circular arc 7c that is radial in the direction of 20 to 40 degrees from the inner circumferential surface 3, and a straight line 7d that is tangent to the circular arc 7c.
It becomes. If the wear is taken out in a straight line in the tangential direction from the innermost circumference of the edge, the strength of the V-shaped groove will increase until the slope on the side that touches the inside of the edge of the figure-7 groove is not created and the slope on one side is separated by a width that can be created. This was done to improve the problem of not being able to remove the gap, and in order to make it as small as possible, the shape described above was adopted.

Moreover, by doing so, the number of the 7-shaped grooves 7 can be increased, and the area of the surface forming the peak 7b can be reduced, thereby improving the holding of the vibration system.

Furthermore, the straight line 7d of the valley bottom 7a ends as a circular arc 7e, but if the straight line 7d ends as the straight line 7d, the strength of the groove 7 at this portion is prevented from becoming too strong.

At the same time, by doing this, the groove 7 comes into contact with the adjacent groove 7, so the groove 7 can be formed without leaving the peak 7b surface on the outer periphery, and the width of the groove 7 can be made uniform. This is possible, and in combination with making the depth m7 uniform on the conical surface 6, the strength of the entire edge portion can be made uniform.

Therefore, even if the edge vibrates up and down, the linearity with respect to its amplitude is improved, no rolling or abnormal noise occurs during operation, and an edge with good characteristics can be obtained.

〔Effect of the invention〕

As described above, by specifying the shape of the V-shaped groove formed in the edge portion as described above, the strength of the entire edge can be made uniform, and there is no difference between the inner periphery and the outer periphery as in the conventional case. will not occur.

Therefore, the magnitude of the vibration of the diaphragm is proportional to the input, and linearity is improved, resulting in good speaker characteristics and reduced distortion.

Further, it has the advantage that the edges do not roll or abnormal noises are not generated.

[Brief explanation of drawings]

1 to 3 show one embodiment of the present invention, in which FIG. 1 is a plan view, FIG. 2 is a sectional view taken along the valley bottom, and FIG.
The cross-sectional view taken along the line E-E in the figure, and Figures 4 to 6 show a conventional speaker diaphragm. Figure 4 is a plan view, Figure 5 is a cross-sectional view along the valley bottom, and Figure 6 is 5 is a cross-sectional view taken along line AB and CD in FIG. 4. FIG. 3... Inner circumference circle, 4... Outer circumference circle, 5, 6... Conical surface, 7... V-shaped groove, 7a... Valley bottom, 7b... Mountain top, 7C... Circular arc , 7d...straight line, 7e...circular arc, 7f...wall surface, ab06. Half apex angle, C...Radiation angle, R1...Curved surface radius of valley bottom, R2...Curved surface radius of mountain top.

Claims (1)

[Claims] A plurality of V-shaped grooves are formed so that the bottom of the groove extends from the innermost circumference of the edge at an arc with a radial angle of 20 to 40 degrees to the inner circle, and forms a straight line in the tangential direction of the arc. After that, the edge ends up as a circular arc tangent to the outermost circumferential circle, and the peak part of the groove starts from the end of the conical surface that starts along the innermost inner circumferential circle, and extends to the outermost outer circumferential circle. The depth and width of the groove at that part are the same from the circumference to the outer circumference, and the groove does not overlap on the entire edge surface, and in the vertical direction, the groove is arc-shaped. A diaphragm for a speaker, characterized in that the diaphragm is provided at an edge portion so as to have a roll shape.