JPS6324733B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a fluid filter, and is effective for use in, for example, air filters, oil filters, etc. for automobiles.

(Prior Art) Conventionally, as shown in Japanese Patent Application Laid-Open No. 57-140617, fluid filtration is constructed by continuously bending a fan-shaped or trapezoidal band-shaped filter medium into a cross-sectional shape, and then curving the band-shaped filter medium into a circular shape. In the body, bending lines are attached to the bending position before the body is bent into a wave-like cross-sectional shape.
As shown in FIG. 2, for example, there are two methods for applying the bending lines: heating the scoring blade 101 to a high temperature and applying the bending lines using a heat press; There is a way to add bending lines.

If you try to continuously bend the filter medium with bending lines in this way so that it has a wavy cross section and roll it into a circular shape, the third
As shown in the figure, irregular corners are bent, and when inserted into the shaping mold 105 as shown in Fig. 4, problems such as tearing of the filter medium P and buckling occur as shown in Fig. 5. be. Further, even if the upper surface is well rounded into a circle as shown in FIG. 6a, there is still a problem in that the lower surface is bent at the corners as shown in FIG. 6c.

(Problems to be Solved by the Invention) The present invention solves the problem of the corner bending phenomenon that occurs when a filter medium that is continuously bent in a wavy manner is rolled up.

(Means for Solving the Problems) In the present invention, the following measures were taken to solve the above problems. That is, it has a plate-shaped filter medium whose length dimension at one end is longer than the length dimension at the other end, and this band-shaped filter medium is bent into a wave-shaped cross section between the two ends, and
In this fluid filter body, the filter medium has a curved structure such that the one end side is the outer peripheral side and the other end side is the inner peripheral side, and the filter medium bent in the cross-sectional wave shape has guide lines on at least the inner peripheral side slope of the curved structure. A fluid filter body is provided with a large number of.

(Example) Next, an example of the present invention will be described based on the drawings. FIG. 1 is a perspective view showing a state immediately after the filter medium 10 is bent into a wave shape. Also, Figure 7 shows the filter medium 1.
This shows the state before 0 is bent into a wave shape.
FIG. 8 is an enlarged view of section A in FIG. 7. As can be seen from these figures, the shape of the filter medium 10 before bending is a fan shape, and the bending lines 1 are formed along this fan shape.
A plurality of numbers 2 (11 in this embodiment) are attached.
This bending line 12 is made by applying a high temperature scoring blade to the filter medium 1.
0 by thermocompression bonding. The filter medium 10 provided with the bending lines 12 in this manner is bent into a wave-like cross-sectional shape by a bending device (not shown), as shown in FIG. In this embodiment, five peaks are formed, and the five peaks are designated by symbols a to e from the inside (FIG. 1). A plurality of cut lines 14 are cut at equal intervals on the inner slopes of the mountain parts a to e, going from the top of the mountain part to the valley, that is, from one end where the length of the filter medium 1 is long to the other end. In this example, there are 12 on the slope of mountain part a, 14 on mountain part b, and 16 on mountain part c.
There are 17 ridges in the crest d and 18 ridges in the ridge e. As can be seen from FIGS. 7 and 8, this cut line 14 has an inclination angle θ (θ=30° in this embodiment) with respect to the normal l-l of the bend line 12. The slope is reversed for each mountain. still,
When the inclination angle θ is set to 0°, there may be a portion N where the bending is not possible as shown in the model diagram of FIG. 9, but the conventional irregular corner bending phenomenon will not occur. Further, in this embodiment, the thickness of the cut line 14 is 1 mm, the thickness of the filter medium 10 is 3.2 mm, and the cut depth is 0.2 to 0.5 mm.

Next, the principle of how the filter medium 10 can be reliably bent into a regular polygon without causing corner bending by providing the cut lines 14 will be explained using a simple model diagram.

In order to reliably bend all of the cut lines 14, it is necessary to have ease of bending at the initial stage of bending and difficulty in bending after bending to prevent only one cut line from bending too much. That is, as shown in the model diagram of _FIG .
When the bend is made, a bending stopping moment M ₂ is applied to stop the bending progress.
M ₂ ′ is required. Therefore, as shown in FIG. 11, if a cut line 14 having an inclination angle θ is provided, when a moment M that tends to round the filter medium 10 acts, this moment M tends to bend it along the cut line 14. It is decomposed into a moment M ₁ and a bending stop moment M ₂ . That is,
The above-mentioned ease of bending and the difficulty of bending after bending exist at the same time. Such filter media 1
When 0 is bent, it becomes as shown in FIG. 12, and is regularly bent into a regular polygon along the incision lines 14.

Although the embodiments of the present invention have been described above, the shape of the cut line 14, which is an example of the guide line, may be modified in various other ways. For example, as shown in FIG. 13, the cut lines 14 may be stopped in the middle of the slope instead of extending over the entire slope of the mountain. Further, the cut streaks 14 may be shaped like a mountain wave as shown in FIG. 14, or may be shaped like a series of semi-ovals as shown in FIG. 15. In the above-mentioned embodiment, the directions of the notches 14 were reversed for each ridge, but they may all be oriented in the same direction. Further, as a method for forming the bending lines 12 and the cutting lines 14, methods such as a hot pressing method, a dielectric method, a cold pressing method, an ultrasonic tracing method, a roller scoring method, a movable spatula method, etc. can be considered.

As an example, FIG. 16 shows a cross section of a streak S formed by the hot pressing method, and FIG. 17 shows a cross section of a streak S formed by the cold pressing method. The filter medium 10 consists of three layers: a dense layer 10a, an intermediate layer 10b, and a coarse layer 10c.

Although the rounded shape of the filter medium 10 is a regular polygon M that approximates a perfect circle R as shown in FIG. 18, it is also possible to form a polygon that approximates an ellipse.

(Function) In the present invention, when the filter medium is rolled up, a large number of guide lines are provided, which ultimately act as guide lines, and the filter medium is accurately rolled up along these guide lines.

(Effects of the Invention) Therefore, it is possible to round the polygon into an accurate polygon that approximates the desired shape without causing the irregular corner bending phenomenon that occurs in the conventional case.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing a filter medium according to an embodiment of the present invention, FIG. 2 is a perspective view showing a conventional example, FIG. 3 is a plan view of the conventional example, and FIG. 4 is a perspective view showing the conventional example during shaping. Fig. 5 is a partial sectional view showing a conventional example, Fig. 6 shows a conventional example, in which a is a plan view, b is a front view, c is a bottom view, and Fig. 7 is a plan view of the filter medium of the embodiment. Figure 8 is a detailed view of part A in Figure 7, Figure 9 is a model diagram of the filter medium, Figures 10, 11, and 12 are model diagrams for explaining rounding of the filter medium, and Figures 13 and 14. Figure, 1st
FIG. 5 is a diagram showing a modified example of the cut streak, FIGS. 16 and 17 are cross-sectional views of the streak, and FIG. 18 is a model diagram showing a rounded shape. 10... Filter medium, 12... Bending line, 14... Cutting line.

Claims (1)

[Scope of Claims] 1. A plate-shaped filter medium whose length at one end is longer than the length at the other end, the plate-shaped filter medium is bent between both ends into a wave-shaped cross section, and the filter medium is bent at the one end. In a fluid filter having a curved structure such that one side is an outer circumferential side and the other end side is an inner circumferential side, a large number of guide lines are provided at least on the inner circumferential side slope of the curved structure of the filter medium bent in the cross-sectional wave shape. Fluid filter. 2. The fluid filter according to claim 1, wherein the plurality of guide lines are cut lines. 3. The fluid filter according to claim 1 or 2, wherein the plurality of guide lines are provided at an angle with respect to the inner peripheral side slope of the filter medium. 4. The fluid filter according to claim 1 or 2, wherein the plurality of guide lines are provided linearly with respect to the inner peripheral side slope of the filter medium. 5. Any one of claims 1 to 4, wherein the guide line is provided on the inner peripheral side slope of the filter medium from the one end to the other end of the filter medium. The fluid filter body described in .