JP2016022660A - Screen changer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a screen changer that improves sealing performance while ensuring the smoothness of sliding movement in a screen unit.SOLUTION: A screen changer comprises: a screen unit 4 where a plurality of filter sets 10 including a screen 12 for filtration are juxtaposed in a slide plate 9; a case body 3 having a guide hole 8 sliding-movably guiding the screen unit 4; and a seal ring 15. The seal ring 15 comprises a base part 15A held by the screen unit 4 and a seal part 15B extending radially inward from the base part 15A. The seal part 15B is interposed between a first side surface S1 of the guide hole 8 and a second side surface S2 of the filter set 10, and a space part 16 having a substantially V-shaped cross section widening in a radially inward direction is arranged between the seal part 15B and the second side surface S2.SELECTED DRAWING: Figure 5

Description

  The present invention relates to a screen changer for filtering an extruded material from an extruder, and in particular, easily seals the leakage of the extruded material from a gap between a screen unit and a guide hole for slidably guiding the screen unit. It relates to a screen changer.

  As a device for filtering an extruded material such as rubber extruded from an extruder, for example, a slide type screen changer is known. For example, as shown conceptually in FIG. 6, this type of screen changer a includes a case main body a1 fixed to the front end of the extruder b, and an X-axis direction supported by the case main body a1 and perpendicular to the extrusion direction. And a screen unit a2 that can slide. The screen unit a2 includes a slide plate d that passes through a guide hole c provided in the case main body a1, and a plurality of (for example, two) filtration screens f that are attached to the slide plate d.

  When one screen f is clogged, the screen unit a2 can be switched to the other new screen f by changing the position of the screen unit a2 in the X-axis direction.

  Here, in order to smoothly slide the screen unit a2, a slight gap g is formed between the guide hole c and the screen unit a2. However, this causes a problem that a part of the extruded material leaks from the gap g. In particular, on the rear side (upstream side) in the extrusion direction with respect to the screen f, the pressure P becomes higher due to the passage resistance of the screen f and the like, and thus leakage occurs remarkably.

  Therefore, in Patent Document 1 below, as shown in FIG. 6, it is described that a ring-shaped sealing material h that is attached to the side surface of the guide hole c and seals between the screen unit a2 is provided. Such a sealing material h has a constant pressure contact force with the screen unit a2. For this reason, when the pressure contact force is set to be large, the resistance when the screen unit a2 is slid is increased, resulting in a loss of smoothness. On the contrary, when the pressure contact force is set small, the sealing effect becomes insufficient, and there is a tendency for leakage to occur from the gap g1 on the rear side in the extrusion direction with respect to the screen f. Thus, there is a tradeoff between smoothness of slide movement and sealing performance, and it has been a difficult problem to sufficiently satisfy both.

JP-A-6-320533

  Therefore, an object of the present invention is to provide a screen changer that can improve the sealing performance while ensuring smoothness of sliding movement in the screen unit.

The present invention is a sliding screen changer having a screen for filtering extruded material from an extruder,
A case body having a guide hole fixed in the front end of the extruder and extending in the X-axis direction perpendicular to the extrusion direction;
A screen unit in which a plurality of filtration sets including the screen for filtration and a breaker plate are arranged in parallel in the X-axis direction on a slide plate guided so as to be slidable in the X-axis direction in the guide hole;
And a first side surface which is a side surface on the rear side in the extrusion direction of the guide hole, and a seal ring for sealing between the screen unit,
Between the seal ring and the screen unit, a gap portion having a substantially V-shaped cross section that becomes wider toward the inside in the radial direction is provided, and a part of the extruded material from the extruder flows into the gap portion. The whole seal ring moves to the rear side in the extrusion direction and is pressed against the first side surface to seal between the first side surface.

  In the screen changer according to the present invention, the filtration set includes a screen holding ring disposed on the rear side in the extrusion direction of the screen, and between the side surface on the rear side in the extrusion direction of the screen holding ring and the seal ring. It is preferable that the screen holding ring press and hold the screen against the breaker plate when the gap is formed and a part of the extruded material from the extruder flows into the gap.

  In the screen changer according to the present invention, it is preferable that the seal ring protrudes rearward in the pushing direction from the side surface of the slide plate and has a gap of 3 mm or more between the first side surface and the slide plate. .

  As described above, the present invention includes a seal ring that seals between the first side surface of the guide hole and the screen unit, and is widened radially inward between the seal ring and the screen unit. A gap having a substantially V-shaped cross section is formed.

  Therefore, a part of the extruded material from the extruder flows into the gap portion in a wedge shape. Here, the pressure of the extruded material is high during the operation of the extruder. Therefore, during the operation of the extruder, the wedge-shaped extruded material flowing in at a high pressure causes the entire seal ring to move rearward in the extrusion direction and be strongly pressed against the first side surface. As a result, it is possible to improve the sealing performance between the first side surface and the seal ring, and thus between the first side surface and the screen unit.

  Conversely, when the screen is switched, the operation of the extruder is stopped. For this reason, the pressure of the extruded material is lowered, and the pressing force against the first side surface of the seal ring is also reduced accordingly. As a result, resistance when sliding the screen unit is reduced, and smoothness can be ensured.

It is a perspective view which shows one Example of the screen changer of this invention. It is the fragmentary sectional view which looked at the screen changer from the upper part. It is a disassembled perspective view which shows a screen unit. It is sectional drawing which looked at the screen unit from the side. It is the elements on larger scale which show the peripheral part of a seal ring. It is sectional drawing which shows an example of the conventional screen changer.

Hereinafter, embodiments of the present invention will be described in detail.
As shown in FIGS. 1 and 2, the screen changer 1 of the present embodiment is a slide type screen changer that filters the extruded material from the extruder 2. The screen changer 1 includes at least a block-like case body 3 fixed to the front end of the extruder 2 and a slidable screen unit 4 having a filtering screen 12.

  The extruder 2 is an extruder that extrudes while extruding an extruded material such as unvulcanized rubber or resin, for example, and those having various conventional structures are preferably employed. The extruder 2 of this example includes a cylinder barrel 5 extending in the extrusion direction and a screw shaft 6 accommodated in the cylinder barrel 5. And the extrusion material thrown in from the hopper 5A is extruded from the discharge port 5B opened at the front end of the cylinder barrel 5 by the rotational drive of the screw shaft 6 by the electric motor.

  Next, the case main body 3 of the screen changer 1 is fixed to the front end of the cylinder barrel 5. The case body 3 includes a material flow path 7 that receives the extruded material from the extruder 2 and a guide hole 8 that guides the screen unit 4.

  The material flow path 7 continues to the discharge port 5B and extends in the extrusion direction. The guide hole 8 has, for example, a rectangular cross section, extends in the X-axis direction perpendicular to the extrusion direction, and intersects the material flow path 7. By this intersection, the material flow path 7 is divided into a first flow path part 7A on the rear side in the extrusion direction from the crossing position and a second flow path part 7B on the front side.

  The screen unit 4 includes a slide plate 9 that is slidably guided in the guide hole 8 in the X-axis direction, and a plurality (two in this example) of filtration sets 10 that are attached to the slide plate 9. .

  As shown in FIGS. 3 and 4, the slide plate 9 is provided with a plurality of storage holes 11 for storing and holding the filtration sets 10 concentrically in the X-axis direction. The storage hole 11 of this example is formed in a stepped hole shape having a first hole portion 11A on the rear side in the extrusion direction with a large inner diameter and a second hole portion 11B on the front side with a small inner diameter.

  Each filtration set 10 includes a mesh screen 12 for filtration and a breaker plate 13 that supports the screen 12. The breaker plate 13 includes a large-diameter first body portion 13A that fills the first hole portion 11A, a small-diameter second body portion 13B that fills the second hole portion 11B, and a rear side of the first body portion 13A. A stepped disk shape having a third body portion 13C having a small diameter that is continuous with the third body portion 13C. Further, the breaker plate 13 is formed with a plurality of small holes 13H through which the extruded material passes by penetrating in the extrusion direction. The screen 12 is adjacent to the breaker plate 13 on the rear side in the extrusion direction.

  The filtration set 10 of this example further includes a screen holding ring 14 disposed on the rear side in the extrusion direction of the screen 12. The screen holding ring 14 has an annular shape extending along the outer peripheral edge of the screen 12, and holds the screen 12 between the screen holding ring 14 and the breaker plate 13.

  The screen changer 1 further includes a seal ring 15 that seals between the first side surface S1 that is the side surface on the rear side in the extrusion direction of the guide hole 8 and the screen unit 4. Further, a gap portion 16 having a substantially V-shaped cross section is provided between the seal ring 15 and the screen unit 4 and becomes wider toward the inside in the radial direction.

As shown in FIG. 5, the seal ring 15 of this example includes a base portion 15A held by the screen unit 4 and a seal portion 15B extending from the base portion 15A along the first side surface S1 inward in the radial direction. In this example, the case where the seal ring 15 has a substantially L-shaped cross section including the base portion 15A and the seal portion 15B is shown.

  The base portion 15A includes an inner peripheral surface 11s of the storage hole 11 (in this example, an inner peripheral surface 11As of the first hole portion 11A) and an outer peripheral surface 13s of the breaker plate 13 (in this example, the third body portion). 13C and the outer peripheral surface 13Cs).

  The seal portion 15B is interposed between the second side surface S2 that is the side surface on the rear side in the extrusion direction of the filtration set 10 and the first side surface S1. In this example, the side surface on the rear side in the extrusion direction of the screen holding ring 14 constitutes the second side surface S2.

  The gap portion 16 is formed between the seal portion 15B and the second side surface S2. The gap 16 communicates with the material flow path 7. In this example, the second side surface S2 forms an inclined surface 17 that is inclined inward in the extrusion direction toward the inside in the radial direction, whereby the gap portion 16 is formed in a substantially V-shaped cross section. It is.

  As described above, the gap portion 16 is formed between the seal portion 15 </ b> B and the second side surface S <b> 2, and the gap portion 16 opens in a substantially V shape with respect to the material flow path 7. Therefore, a part of the extruded material from the extruder 2 enters the wedge portion in the gap portion 16.

  Here, during the operation of the extruder 2, the screen 12 and the breaker plate 13 have a passage resistance, so that the pressure of the extruded material is higher on the rear side than the screen 12. Therefore, during the operation of the extruder 2, the wedge-shaped extruded material entering at a high pressure causes the entire seal ring 15 to slide to the rear side in the extrusion direction and be strongly pressed against the first side surface S1. As a result, it is possible to improve the sealing performance between the first side surface S1 and the seal portion 15B, and thus between the first side surface S1 and the screen unit 4. Conversely, the screen unit 4 is pressed forward in the extrusion direction by the wedge-shaped extrusion material. For this reason, there is no gap between the side surface of the breaker plate 13 on the front side in the extrusion direction and the guide hole 8, and leakage of the extrusion material from this point is prevented even without a seal material.

  On the other hand, when the screen 12 is switched, the operation of the extruder 2 is stopped. Therefore, the pressure of the extruded material is lowered, and the pressing force against the first side surface S1 of the seal portion 15B is also reduced accordingly. As a result, the resistance when the screen unit 4 is slid in the X-axis direction is reduced, and the smoothness of the slide movement can be ensured. In order to further improve the smoothness of the slide movement, as shown in FIG. 5, the seal ring 15 is protruded rearward in the pushing direction from the side surface of the slide plate 9, and the first side surface S <b> 1 and the slide plate 9 are It is preferable to provide a gap D of 3 mm or more between them. Thereby, when the screen unit 4 slides, the slide resistance due to the extruded material that has entered the gap portion 16 can be reduced.

  Further, in this example, the rear side surface of the screen holding ring 14 constitutes the second side surface S2. Therefore, during the operation of the extruder 2, the screen holding ring 14 can strongly press the screen 12 against the breaker plate 13 by the wedge-shaped extruded material that enters at a high pressure. That is, the holding force to the screen 12 can be increased.

  Instead of the second side surface S2, the gap portion 16 may be formed in a substantially V-shaped cross section by making the side surface 15Bs on the front side of the seal portion 15B an inclined surface that is inclined rearward in the extrusion direction. Further, both the second side surface S2 and the side surface 15Bs can be inclined surfaces.

  As shown in FIGS. 1 and 2, the sliding movement of the screen unit 4 is performed by a hydraulic cylinder 20 in this example. Specifically, the cylinder 20 is supported on the side surface of the case body 3 via, for example, a U-shaped mounting base 21. The side surface of the screen unit 4 is connected to the rod end of the cylinder 20 extending in the X-axis direction. Reference numeral 22 in FIG. 1 denotes an extrusion head which is attached to the front side of the screen changer 1 and forms a filtered extrusion member. Reference numeral 23 in FIG. 4 is a bearing member that is attached to the inner surface of the guide hole 8 and reduces the sliding resistance with the screen unit 4 during sliding movement.

  As mentioned above, although especially preferable embodiment of this invention was explained in full detail, this invention is not limited to embodiment of illustration, It can deform | transform and implement in a various aspect.

DESCRIPTION OF SYMBOLS 1 Screen changer 2 Extruder 3 Case main body 4 Screen unit 8 Guide hole 9 Slide plate 10 Filtration set 11 Storage hole 11s Inner peripheral surface 12 Screen 13 Breaker plate 13s Outer peripheral surface 14 Screen holding ring 15 Seal ring 15A Base 15B Seal part 16 Gap Part 17 Inclined surface S1 1st side surface S2 2nd side surface

Claims (3)

A sliding screen changer having a screen for filtering extruded material from an extruder,
A case body having a guide hole fixed in the front end of the extruder and extending in the X-axis direction perpendicular to the extrusion direction;
A screen unit in which a plurality of filtration sets including the screen for filtration and a breaker plate are arranged in parallel in the X-axis direction on a slide plate guided so as to be slidable in the X-axis direction in the guide hole;
And a first side surface which is a side surface on the rear side in the extrusion direction of the guide hole, and a seal ring for sealing between the screen unit,
Between the seal ring and the screen unit, a gap portion having a substantially V-shaped cross section that becomes wider toward the inside in the radial direction is provided, and a part of the extruded material from the extruder flows into the gap portion. The screen changer is characterized in that the whole seal ring moves rearward in the extrusion direction and is pressed against the first side surface to seal between the first side surface.   The filtration set includes a screen holding ring that is disposed on the rear side in the extrusion direction of the screen, and the gap portion is formed between a side surface on the rear side in the extrusion direction of the screen holding ring and the seal ring. 2. The screen changer according to claim 1, wherein a part of the extruded material from the extruder flows into the part, whereby the screen holding ring presses and holds the screen against the breaker plate. 3. The seal ring according to claim 1, wherein the seal ring protrudes rearward in the pushing direction from the side surface of the slide plate, and a gap of 3 mm or more is provided between the first side surface and the slide plate. Screen changer.

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