JPS6213750Y2 - - Google Patents

Description

[Detailed description of the invention] This invention relates to an improvement of a rubber membrane for a membrane press type dehydrator.

As shown in FIG. 1, the membrane compression dehydrator includes a dome 2 having a hemispherical recess 1, a hollow plunger 3 connected to the upper end of the dome 2, a cylinder 4 surrounding the plunger 4, and a cylinder 4 surrounding the dome 2. The rubber film 5 covers the opening surface of the
is in a flat state (FIG. 1A), but the material to be dehydrated 6 is preliminarily agglomerated into blocks by an agglomerator (not shown) in the previous stage and transported to the lower part of the dome 2 by a grate-shaped conveyor 7. Then, suction is performed through the hole 3a in the plunger 3, and the rubber membrane 5 is stretched and brought into close contact with the inner wall of the recess 1 (FIG. 1B), and then high-pressure fluid is supplied into the cylinder 4. The dome 2 descends together with the plunger 3 toward the material to be dehydrated 6 on the conveyor 7, and along with this, a strong fluid pressure of 25 to 75 kg/cm ² is applied to the back surface of the rubber membrane 5 through the hole 3a of the plunger 3. The rubber membrane 5 strongly presses the material to be dehydrated 6 to squeeze out the moisture contained therein, and this moisture is discharged through the hole 7a of the conveyor 7 (FIG. 1C).
It was made to be done.

Rubber membrane 5 used in the membrane compression type dehydrator mentioned above
is subjected to repeated effects of vacuum suction and high pressure,
A fixing part 5 fixed to the periphery of the opening of the recess 1 of the dome 2
a is made of hard rubber, and the central pressing part 5b is made of soft rubber.

However, since the rubber materials (especially elongation rates) of the two parts 5a and 5b are different, during vacuum suction,
The interface between the two parts 5a and 5b was subjected to significant stress, and cracks often occurred along the interface, and the resulting cost of purchasing a new rubber membrane and the time required to replace the rubber membrane were major drawbacks of this dehydrator. .

Therefore, an object of the present invention is to provide a rubber film in which the occurrence of the above-mentioned cracks is suppressed as much as possible.

The present invention has been made to achieve the above object by following the behavior of the rubber membrane, suppressing the movement of the corners of the rubber membrane, and minimizing the formation of boundary surfaces near the damaged area.

Fig. 2 shows the behavior of the corner C of the rubber membrane 5 during vacuum suction, and Fig. 3 shows the behavior during compression. When subjected to inward tensile force and compressed, the corner C
This causes scratches on the conveyor 7 to protrude outward, and in particular, with the conventional rubber membrane, the edge of the interface between the hard rubber layer 5a and the soft rubber layer 5b as shown by the dotted line in FIG. is located near the corner C, so the scratches grow and promote delamination at the interface between the two parts 5a and 5b.

Therefore, the present invention has a rubber membrane 5 as shown in FIG.
The fixed part hard rubber layer 5a and the compressed part soft rubber layer 5b
The outer end i' in the radial direction of the boundary surface i with It is positioned radially inward from position W.

The thickness of the compressed part soft rubber layer 5b is about 13 mm, and the other end A of the boundary surface A is formed at least 3 mm away from the upper surface B of the pressed part soft rubber layer 5b. preferable.

In FIG. 4, 2 is a dome, 9 is a ring pressing member attached to the inner surface of the dome 2, 10 is a reinforcing fabric such as polyamide cloth applied to the outer surface of the fixed part hard rubber layer 5a, and 11 is a reinforcing fabric such as a polyamide cloth. This is a reinforcing cloth such as polyamide cloth embedded in multiple layers in the attachment ring contact portion of the fixed portion hard rubber layer 5a.

The one in Fig. 4 above is during vacuum suction and compression,
Since the corner part c of the rubber membrane 5 is composed only of the hard rubber layer 5a, the movement of the part C is suppressed as much as possible, and the boundary between the fixed part hard rubber layer 5a and the compressed part soft rubber layer 5b is Since the starting end of the surface A is located as far away from the region that is subjected to the strong compressive action by the attachment ring 8 as possible, stress concentration on the boundary surface A can be avoided as much as possible.

FIG. 5 shows another embodiment in which the radial outer end I' of the boundary surface I between the fixed part hard rubber layer 5a and the compressed part soft rubber layer 5b of the rubber membrane 5 is attached to the mounting ring 8.
Starting from a position W where an imaginary perpendicular line Q drawn from the lowest point P of the circumferential surface to the lower surface of the rubber membrane intersects with the lower surface of the rubber membrane 5 or radially inside from the position W, continuing to the circumferential surface of the mounting ring 8 It is formed so as to be curved so as to be substantially parallel to the upper surface of the compressed portion soft rubber layer 5b, and to end at a portion that extends substantially parallel to the upper surface of the compressed portion soft rubber layer 5b. With this configuration, since the intermediate portion of the boundary surface A between the fixed part hard rubber layer 5a and the compressed part soft rubber layer 5b of the rubber membrane 5 is formed in advance in a shape corresponding to the bent state during vacuum suction, Stress concentration acting on the interface A can be further reduced.

As explained above, according to the rubber membrane of the present invention,
By suppressing the movement of the corner as much as possible and placing the boundary surface away from the corner, the occurrence of cracks is suppressed as much as possible and the durability of the rubber film is improved. Furthermore, the production method is almost the same as that of conventional rubber membranes, and it is only necessary to change the boundary surface, so it can be implemented at low cost and the cost will not increase.

[Brief explanation of the drawing]

Fig. 1 is a model diagram explaining the operating principle of a membrane compression type dehydrator, Fig. 2 is an enlarged explanatory diagram showing the behavior of the corner of the rubber membrane during vacuum suction, and Fig. 3 is an explanatory diagram of the behavior during compression. FIG. 4 is an enlarged sectional view of the main part of the rubber membrane according to the present invention, and FIG. 5 is an enlarged sectional view of another embodiment. 5...Rubber film, 5a...Fixing part hard rubber layer, 5
b... Soft rubber layer at pressed part, A... Boundary surface, C...
Rubber membrane corner, 8...Mounting ring, 2...Dome.

Claims (1)

[Scope of Claim for Utility Model Registration] (1) The outer edge in the radial direction of the interface between the hard rubber layer of the fixed part and the soft rubber layer of the compressed part of the rubber membrane extends from the lowest point of the circumferential surface of the mounting ring to the A rubber membrane for a membrane compression type dehydrator, characterized in that it is formed so that an imaginary perpendicular line drawn down to the lower surface of the membrane intersects with the lower surface of the rubber membrane or is located radially inward from the position. (2) The boundary surface between the hard rubber layer of the fixed part and the soft rubber layer of the compressed part is such that the outer end in the radial direction is an imaginary perpendicular drawn from the lowest point of the circumferential surface of the mounting ring to the lower surface of the rubber membrane. Starting from a position where it intersects with the lower surface of the rubber membrane or radially inward from the position, it continues to curve so as to be approximately parallel to the circumferential surface of the mounting ring,
The rubber membrane according to claim (1) of the utility model registration, wherein the rubber membrane is further formed to end at a portion extending substantially parallel to the upper surface of the pressed soft rubber layer.