JP2001315120A - Elasticizer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain resin pellets, of which the cut end surfaces are cleanly arranged at a right angle to the axis of a resin strand and the cut lengths are uniform, having stable quality. SOLUTION: An elasticizer is constituted of a rotary blade 12 having continuous edges 11 crossing a rotary direction, a pair of upper and lower feed rolls 13 and 14 arranged in parallel to the axis of the rotary blade 12, the fixed blade 15 arranged between the feed roll 13 and the rotary blade 12 and the guide plate 16 arranged between the feed roll 14 and the rotary blade 12. The gap between a pair of the upper and lower feed rolls and the gap between the fixed blade and the guide blade are used as a strand feed-out passage 32 for feeding out the resin strand 17 toward the rotary blade 12. The feed roll 14 and the guide plate 16 both of which are positioned on the same side with respect to the strand feed-out passage are supported by the movable frame 18 rciprocally movable toward the strand feed-out passage. The gap 19 between the surface 28 opposed to the strand feed-out passage of the guide plate 16 and the peripheral surface of the feed roll 14 is set to 2 mm or less.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cutting device called an elastizer, which cuts a thermoplastic resin strand into small and fixed lengths and mainly produces resin pellets used as a raw material of a plastic molded product. is there. The resin strand as a raw material of the resin pellet is manufactured by extruding a thermoplastic resin from a heating extruder. For this reason, in order to continuously produce resin pellets, it is desirable to provide an elastizer in a portion following a water tank that cools the resin strand extruded from the heating extruder.

[0002]

2. Description of the Related Art Conventionally, an apparatus called a pelletizer has been used for an elastizer. This pelletizer is composed of a rotary blade, a pair of upper and lower feed rolls for feeding a strand toward the rotary blade, and a fixed blade provided between the feed roll and the rotary blade and cooperating with the rotary blade to cut the strand. It is configured. The fixed blade is provided between the lower feed roll and the rotary blade in the pair of upper and lower feed rolls, that is, below the delivery path of the strand sent out from the pair of upper and lower feed rolls, and the rotary blade faces the fixed blade downward. And the resin pellets cut in the meantime fall along the rotation direction of the fixed blade.

[0003] However, although the conventional pelletizer is suitable for cutting a strand having high hardness, it is cooled through a water tank, but is extruded from a heating extruder, is preheated, and has a high viscosity like a rubber string. It is not suitable for a flexible resin strand in the state of an elastic elastomer. Because, in the preheated resin strand in the elastomer state, the tip protruding from the fixed blade touches the fixed blade and vibrates up and down, and the distance from the feed roll to the blade edge of the rotary blade is long, and the The long protruding elastomeric resin strand touches the fixed blade and is pushed back or pulled and vibrates back and forth, and as a result, the cut surface of the obtained resin pellet is inclined with respect to the axis of the resin strand. In this case, the resin pellets having uniform shapes and stable quality cannot be obtained.

[0004]

In order to improve this point, the present inventor provided a fixed blade above the resin-strand delivery passage, and acted upwardly on the fixed blade with a rotating blade. A guide roll is provided between the feed roll and the rotary blade. The guide roll supports the resin strand from below to prevent it from sagging, and completes a pelletizer that suppresses vibration at the tip of the resin strand.
A patent application has been filed with -93606. In the pelletizer according to the prior application (Japanese Patent Application No. Hei 10-93606), a triangular shape generally surrounded by a resin fed straight, a peripheral surface of the rotary blade, and a peripheral surface of the guide roll is provided at a cutting portion by the rotary blade and the fixed blade. Depending on the material of the resin strand, the tip of the resin strand vibrates finely in the triangular gap, and a high-quality resin pellet whose cut surface is aligned at right angles to the axis of the resin strand is formed depending on the material of the resin strand. It turns out that it is not always available.

[0005]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide an elastizer in which the cut surface is neatly aligned at right angles to the axis of the resin strand, the cut length is uniform, and resin pellets of stable quality are obtained. is there.

[0006]

That is, an elastizer according to the present invention comprises a rotating blade 12 having a continuous cutting edge 11 intersecting in the rotating direction, and a pair of upper and lower blades arranged in parallel with the axis of the rotating blade. , A fixed blade 15 arranged between one of the upper and lower feed rolls 13 and the rotary blade 12, and a remaining one of the feed rolls 14 and the rotary blade 12. A main part is constituted by the arranged guide plate 16, and between a pair of upper and lower feed rolls 13 and 14 and a fixed blade 15.
A strand delivery passage 32 for delivering the resin strand 17 toward the rotary blade 12 is formed between the feed roller 14 and the guide plate 16, and the feed roll 14 and the guide plate 16 located on the same side with respect to the strand delivery passage 32 are connected to the strand delivery passage 32. 32. The gap 19 between the surface 28 of the guide plate 16 facing the strand delivery passage 32 and the peripheral surface of the feed roll 14 is 2 mm or less. This is the first feature.

A second feature of the elastizer according to the present invention is that, in addition to the first feature, a guide plate facing the feed roll 14 is provided between the feed roll 14 and the guide plate 16 located on the same side with respect to the strand delivery passage 32. 16 is that the surface 28 is a concave surface 21 having an arc-shaped cross section.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The main part of the elastizer is shown in FIG.
As shown in the figure, a rotary blade 12 having a continuous cutting edge 11 intersecting in the rotation direction, a pair of upper and lower feed rolls 13 and 14 arranged in parallel with the axis of the rotary blade 12, and a pair of upper and lower feed rolls One feed roll 13
The fixed blade 15 is disposed between the rotary blade 12 and the rotary blade 12, and the guide plate 16 is disposed between the remaining one feed roll 14 and the rotary blade 12. Between a pair of upper and lower feed rolls 13 and 14 and a fixed blade 15
A space between the guide plate 16 and the guide plate 16 is a strand delivery passage 32 for delivering the resin strand 17 toward the rotary blade 12.

The feed roll 14 and the guide plate 16 located on the same side with respect to the strand delivery passage 32
Are supported by a movable frame 18 that can reciprocate toward a strand delivery passage. The surface 28 of the guide plate 16 facing the feed roll 14 on one side of the strand delivery passage is an arc-shaped concave surface 21 centered on the axis 20 of the feed roll 14. The gap 19 between the surface 28 of the guide plate 16 facing the strand delivery passage and the peripheral surface of the feed roll 14 is 0.2 mm.
It is almost equal to nothing before and after, and there is a feed roll 1 between them
4 is in a close contact state in which the rotation of 4 is not hindered. The fixed blade 15 is screwed to a support bed 22 fixed to the elastizer body frame. Fixed blade edge 31
Is slightly protruded toward the rotary blade side (12) from the support bed 22, and can be polished as needed without being hindered by the support bed 22. Similarly to the guide plate 16, the surface of the fixed blade 15 facing the feed roll 13 may also be an arc-shaped concave surface 33.

In the fixed blade 15 and the guide plate 16 having such concave surfaces, the upper and lower upper surfaces 2 of the concave surfaces 21 and 33 are formed.
8.34 and lower surface 36/35 as flanges, concave portion 2
Since it has a cross section similar to a C-section steel with 1.33 as a web,
Even if the thicknesses e and f of the concave portions 21 and 33 are reduced, the strength becomes stable. Therefore, the concave portion 21
33, the thickness e · f is reduced, and the rotating blades 12 from the feed rolls 13 and 14 are reduced to an extent corresponding to their thickness e · f.
Distance can be shortened. When the gap between the concave surfaces 21 and 33 and the feed rolls 13 and 14 is narrow at the entrance (37) on the strand delivery passage side and wide at the exit 38 in the rotation direction of the feed roll (FIG. 2), the entrance The gap (19) at (37) is 0.2
It becomes easy to make it almost equal to nothing (zero) around mm.

The upper surface 28 of the guide plate 16 facing the strand delivery passage 32 can be formed of a thin plate such as a doctor blade. In this case, a C-shaped steel (channel) is used for the guide plate 16, the web of the C-shaped steel is opposed to the feed roll 14, and a doctor blade (sheet) is attached to the upper flange (28) of the C-shaped steel.
Should be attached. When such a C-shaped steel is used, the surface (21) of the guide plate 16 facing the feed roll 14 becomes a web surface of the C-shaped steel sandwiched between upper and lower flanges, and the edge of the upper flange of the C-shaped steel. Face the feed roll 14.

The movable frame 18 is supported by an arm 29 and protrudes from the elastic frame body frame.
3 is pulled down by the air cylinder 24 when setting the resin strand, and is pushed up by the air cylinder 24 when cutting the resin strand (when the elastizer is continuously operated). The resin strand 17 is set side by side on the lower feed roll 14 which is lowered and separated from the upper feed roll 13, and then the lower feed roll 14 is raised and pressed against the upper feed roll 13, and the upper and lower feed rolls 13, 14 are rotated. Then, it is sent to the rotary blade 12 and undergoes a cutting (shearing) action. On the upper surface 28 of the guide plate 14, in order to prevent the resin strands 17 from swaying and to make it easier to set the resin strands 17 on the lower feed roll 14 at regular intervals, the adjacent resin strands (17. 17) Partition groove 25 for partitioning
It is good to attach. Upper feed roll 13 shown
Is composed of a rubber roll, and the lower feed roll 1
4 is constituted by a metal roll.

[0013] A large number of resin strands 1 are supplied from the heating extruder.
7 are extruded in parallel in the form of a beam, cooled through the water tank so that they can be cut, and fed rolls 13 and 14.
Drawn into. Since the resin strands 17 are extruded while being aligned in a large number of beams, the feed roll 1
A groove 26 into which the resin strands 17 are divided and fitted one by one is preferably provided along the rotation direction on the peripheral surface of 4. When such a grooved feed roll 14 is used, the unevenness 27 that fits into the groove 26 on the peripheral surface of the feed roll 14 is formed at the corner (edge) of the guide plate 16 facing the strand delivery passage 32 and the peripheral surface of the feed roll 14. In the longitudinal direction of the guide plate 16 (parallel to the axis of the feed roll) in a saw-toothed or wavy shape.
A gap (19) corresponding to the depth of the groove 26 is not formed between the feed roll 14 and the upper surface 28 of the guide plate 16 facing the strand delivery passage 32. The irregularities 27 at the corners are continuous with the concave surface 21 of the guide plate 16 facing the feed roll 14, and the concave groove 21 is formed by forming an arc-shaped groove continuous with the axis 20 of the feed roll 14 along the rotation direction of the feed roll 14. It may be formed.

In the embodiment shown in FIG. 1, a fixed blade 15 is provided above the strand delivery passage, and a guide plate 1 is provided below.
6 is provided, but when the grooves (25, 27) are not formed in the feed roll 14 and the guide plate 16, the guide plate 16 is provided above the strand delivery passage, and the fixed blade 15 is provided below the strand delivery passage. It may be provided. In that case, feed roll (14) and guide plate (1)
6) is driven up and down on the upper side of the strand delivery passage, and the resin strand 17 is set on the lower feed roll (13) and the fixed blade (15) when it rises.

[0015]

According to the present invention (claim 1), a guide plate 16 is provided instead of the guide roll in the prior application (Japanese Patent Application No. 10-93606), and the guide plate 16 is fixed to the fixed blade 15 with the strand delivery passage interposed therebetween. Since it is provided facing each other, the feed roll 14 and the rotary blade 12 can be approached,
Accordingly, the length of the resin strand 17 protruding from the feed roll 14 to the rotary blade 12 can be reduced, and as a result, the rotary blade 1
Expansion and contraction and runout at the protruding portion of the resin strand 17 protruding to the second side are reduced.

Further, the guide plate 16 can be brought close enough to touch the rotary blade 12, and the guide plate 16
A gap (19) can be eliminated between the rotary blade 12 and the rotary blade 12 and between the guide plate 16 and the feed roll 14, and as a result, the upper and lower portions of the tip 30 of the resin strand 17 at the cutting site between the rotary blade 12 and the fixed blade 15 can be eliminated. Deflection and deflection can be eliminated, and the lengths of the cut resin pellets can be made uniform, and the cut surfaces can be aligned at right angles to the axis of the resin strand 17 to obtain stable quality resin pellets. .

Feed roll 14 and guide plate 16
Are supported by the same movable frame 18, so that when setting and cleaning the resin strand 17 and raising and lowering the feed roll 14, there is no need to adjust the gap 19 between the feed roll 14 and the guide plate 16 at all. The gap 1 between the surface 28 of the guide plate 16 facing the strand delivery passage and the peripheral surface of the feed roll 14
Since the gap 9 is substantially 2 mm or less and the gap 19 is substantially eliminated, the resin pellet 17 can be efficiently obtained without the resin strand 17 being fitted between the gaps. so,
Since no adjustment mechanism for adjusting the gap 19 between the feed roll 14 and the guide plate 16 is required,
The distance from the feed roll 14 to the rotary blade 12 can be reduced, and the elastizer can be easily manufactured and handled.

According to the present invention (claim 2), the surface 28 of the guide plate 16 facing the feed roll 14 on one side of the strand delivery passage 32 is formed as an arc-shaped concave surface 21 having substantially the same radius of curvature as the feed roll 14.
The guide plate 16 can be formed by cutting the surface of the hard plate.

The guide plate 16 having such an arcuate concave surface 21 has a cross section of the upper and lower upper surfaces 28 of the concave surface 21.
And the lower surface 36 as a flange and the concave portion 21 as a web, so that the shape becomes similar to a C-shaped steel. Therefore, even if the thickness e of the concave portion 21 is reduced, the strength is stable, and the thickness corresponds to the thickness e. In addition, the distance from the feed roll 14 to the rotary blade 12 can be reduced.

By doing so, the projecting length of the resin strand 17 sent out from the feed roll 14 is shortened, so that the deflection or bending of the tip 30 of the resin strand 17 at the cut portion is more reliably prevented, and a high-quality resin Pellets can be obtained.

[Brief description of the drawings]

FIG. 1 is a perspective view of a main part of an elastizer according to the present invention.

FIG. 2 is a sectional view of a main part of the elastizer according to the present invention.

[Explanation of symbols]

 REFERENCE SIGNS LIST 11 blade tip 12 rotary blade 13 feed roll (rubber roll) 14 feed roll (metal roll) 15 fixed blade 16 guide plate 17 resin strand 18 movable frame 19 gap 20 feed roll shaft 21 concave surface 22 support bed 23 support post 24 air cylinder 25 partition groove 26 groove 27 Irregularities 28 Surface (upper surface) facing delivery path 29 Arm 30 Tip of resin strand 31 Cutting edge 32 Strand delivery path 33 Concave surface 34 Upper surface 35/36 Lower surface 37 Inlet portion 38 Exit portion

Claims (2)

[Claims] 1. A rotary blade (12) having a continuous blade edge (11) crossing in the rotation direction, and a pair of upper and lower feed rolls (13, 14) arranged in parallel with the axis of the rotary blade (12).
14), a fixed blade (15) disposed between one of the upper and lower feed rolls (13) and the rotary blade (12), and the remaining one of the feed rolls (14). A guide plate (16) disposed between the rotary blades (12) forms a main part of the elastizer, and the upper and lower pair of feed rolls (13
14) and between the fixed blade (15) and the guide plate (1).
6) is a strand delivery path (32) for delivering the resin strand (17) toward the rotary blade (12), and the feed roll (14) located on the same side with respect to the strand delivery path (32). ) And the guide plate (16) are supported by a movable frame (18) that can reciprocate toward the strand delivery passage (32), and the strand delivery passage (32) of the guide plate (16).
An elastizer characterized in that a gap (19) between a surface (28) facing the surface and a peripheral surface of the feed roll (14) is 2 mm or less. 2. The feed roll (14) and the guide plate (16) located on the same side with respect to the strand delivery passage (32) according to claim 1, wherein the guide plate (16) faces the feed roll (14). 2. An elastizer according to claim 1, wherein the surface (28) is a concave surface (21) of arcuate cross section.