JP4228235B2 - Production equipment for thermoplastic resin granules - Google Patents

Description

  The present invention relates to an apparatus for producing a thermoplastic resin granule for producing a thermoplastic resin granule by cutting a strand of a thermoplastic resin, and in particular, to extend the life of a cutter for cutting the strand of a thermoplastic resin, and The present invention relates to an apparatus for manufacturing a thermoplastic resin granular material capable of preventing oblique cutting.

As shown in FIG. 4, a conventional thermoplastic resin particulate manufacturing apparatus 50 includes a plurality of nozzles of a die head (not shown) that melts and stores a thermoplastic resin and is extruded onto an inclined trough 54. The strand 10 is caused to flow down to the lower end while being solidified by the cooling water supplied from the upper end of the inclined trough 54, and a desired value is obtained between the cutter 58 and the fixed blade 59 via a take-up roller 57 installed at the lower end. Cut to length.
However, in such a thermoplastic resin particle manufacturing apparatus 50, the flow-down positions of the plurality of strands 10 moving along a number of channels provided on the inclined trough 54 are substantially constant. Therefore, the rotary blade and the fixed blade 59 of the cutter 58 for cutting the strand 10 always cut the strand 10 at the same place, and the strand 10 is attached to the rotary blade and the fixed blade 59 of the cutter 58 after a long period of use. Groove marks 60 (FIG. 5) due to wear occur in the abutting portion. And once such a groove mark 60 is generated, the strand 10 gets stuck in the groove mark 60, and there is a problem that it is difficult to obtain the thermoplastic resin granular material 11 having a clean cut surface and a uniform length. there were.

For this reason, the strand 10 is cut while the cutter 58 is reciprocated in the direction of the rotation axis, and the strand 10 is brought into contact with the blade edge of the rotary blade of the cutter 58 evenly to suppress the generation of the groove marks 60. Although it has been attempted to prolong the service life, there is a problem in that reciprocating the cutter 58 rotating at a high speed in the direction of the rotation axis is highly dangerous in terms of mechanism and the structure becomes complicated. Further, the groove mark 60 of the fixed blade 59 is not eliminated.
Thus, some inventions have been made in which the strand 10 flowing down the inclined trough 54 is reciprocated by some means in a direction orthogonal to the flow-down direction. For example, in Japanese Patent Laid-Open No. 02-500425, a feeding gear having a groove for allowing the strand 10 to flow down is reciprocated. This is realized by reciprocating the groove guide for guiding the strand.
As shown in FIG. 6, the present inventors also have a rectifying guide 34 b constituting a part of the inclined trough 34, or a thermoplastic resin granular material provided with a reciprocating means 36 for reciprocating the rectifying guide 34 b and the lower trough 34 c connected thereto. The manufacturing apparatus 30 of a thing is invented (Unexamined-Japanese-Patent No. 2003-200417).
Japanese Patent Laid-Open No. 02-500425 Japanese Patent Laid-Open No. 06-218728 JP 2003-200417 A

However, when cutting the strand by reciprocating the strand as described above, the cutting edge of the rotary blade of the cutter has a spiral shape with an angle of 1 to 4 degrees with respect to the rotation axis. The force applied by the rotary blade to the strand generates a component force in the direction along the cutting edge of the fixed blade. When the strand 10 reciprocates at 0.03 mm / s or more, the blade moving direction of the rotary blade and the moving direction of the strand Are equal to each other, the component force in the direction along the cutting edge of the fixed blade exceeds the static frictional force between the upper surface of the fixed blade and the strand generated by the rotating blade pressing the strand against the fixed blade, and the strand slides sideways. As a result, there arises a problem that the cut surface is inclined.
In view of the above problems, the present invention provides an apparatus for producing a thermoplastic resin granular material that prevents side slip at the time of cutting associated with reciprocating movement of a strand, thereby extending the life of the cutter and preventing the strand from being obliquely cut. It is.

The present inventor has solved the above problem by the following means.
(1) The molten thermoplastic resin is continuously discharged from a plurality of nozzles, and flows into an inclined trough disposed below the nozzle together with cooling water to form a plurality of strands of thermoplastic resin, and then a desired In the manufacturing apparatus for thermoplastic resin granules cut into lengths into chips, a traverse guide that repeatedly reciprocates a part of the upper surface of a cutter vicinity in the postscript section of the inclined trough in a direction perpendicular to the flow direction of the strand If, Ri Na and and a cutter having a fixed blade having a number of fine grooves that are engraved in parallel to the running direction of the strand cutting edge top surface, and the narrow groove of the cutting edge the upper surface of the fixed blade, the depth An apparatus for producing a thermoplastic resin granular material, having a thickness of 0.3 mm to 0.7 mm, and an interval between adjacent narrow grooves of 0.7 mm to 1.5 mm .
(2) The molten thermoplastic resin is continuously discharged from a plurality of nozzles, and flows into an inclined trough disposed below the nozzle together with cooling water to form a plurality of strands of thermoplastic resin, and then a desired In the manufacturing apparatus for thermoplastic resin granules cut into lengths into chips, a traverse guide that repeatedly reciprocates a part of the upper surface of a cutter vicinity in the postscript section of the inclined trough in a direction perpendicular to the flow direction of the strand And a cutter provided with a fixed blade having a large number of fine grooves carved in parallel to the running direction of the strand on the upper surface of the blade tip, and the traverse guide has a moving speed of 0.03 mm / s to in 0.003 mm / s, all SANYO travel distance repeated reciprocation of 5 to 15 mm, also the narrow groove of the cutting edge the upper surface of the fixed blade, the depth 0.3mm~0.7m In apparatus for producing a thermoplastic resin granules, wherein the spacing between adjacent fine grooves is 0.7Mm～1.5Mm.

The following effects are exhibited by the present invention.
(A) Since the position of the strand that contacts the rotary blade is moved by the traverse guide, all the positions of the rotary blade and the fixed blade are used and evenly worn, so the life of the cutter can be extended.
(B) In addition, since a narrow groove for preventing side-sliding of the strand is provided on the upper surface of the fixed blade, side-sliding at the time of cutting of the reciprocating strand by the traverse guide is eliminated, so that there is no oblique cutting of the strand and the shape is uniform. A thermoplastic resin granular material can be manufactured stably.

Embodiments of the present invention will be described with reference to the drawings of the examples.
FIG. 1 is a structural explanatory view of a thermoplastic resin granular material manufacturing apparatus according to the present invention, FIG. 2 is a detailed explanatory view of a traverse guide and a cutter portion, and FIG. 3 is a perspective view of an embodiment of a fixed blade.
In the figure, 1 is a thermoplastic resin particle production apparatus, 2 is a die head, 3 is a nozzle, 4 is an inclined trough, 4a is an upper flap, 4b is a rectifying guide, 4c is a lower flap, 5 is a traverse guide, and 6 is reciprocating. Moving means, 7 is a take-up roller, 8 is a cutter, 8a is a rotary blade, 9 is a fixed blade, 9a is a narrow groove, 10 is a strand, 11 is a granular material, 12 is a cooling water tank, 12a is a cooling water outlet, 12b is a cooling water inlet, 13 is a cooling water spray.

An apparatus 1 for producing a thermoplastic resin granular material according to the present invention comprises an inclined trough comprising a die head 2, a cold water tank 12, an upper flap 4a, a rectifying guide 4b and a lower flap 4c as shown in FIG. 4, reciprocating means 6 for reciprocating the straightening guide 4b or the straightening guide 4b and the lower flap 4c, a take-up roller 7 for feeding the strand 10 to the cutter 8, a cutter 8 and a fixed blade 9 for cutting the strand 10, and cooling It consists of a water spray 13.
As shown in FIG. 3, narrow grooves 9a having a depth of 0.3 mm to 0.7 mm are formed on the upper surface of the fixed blade 9 at intervals of 0.7 mm to 1.5 mm . In FIG. 3, the cross section of the narrow groove 9a is shown as a triangle. However, the present invention is not limited to this, and the narrow groove 9a may have a quadrangular or U-shaped cross section.

The die head 2 temporarily melts thermoplastic resin such as polyamide, polyethylene, polyolefin, propylene homopolymer and copolymer, 4-methylpentene-1 polymer, vinyl chloride homopolymer and copolymer, polyethylene terephthalate, polyamide and polystyrene. In the lower part of the die head 2, a plurality of nozzles 3 for simultaneously pushing out a plurality of strands 10 are linearly arranged on the upper flap 4a so as to cross the upper flap 4a. Yes.
The plurality of nozzles 3 are preferably arranged at intervals such that the plurality of strands 10 pushed out from the die head 2 are formed without sticking to each other.

The strand 10 pushed out from the nozzle 3 is suspended in a channel (not shown) provided in the upper flap 4a along the longitudinal axis direction. The channel is for preventing adhesion between the adjacent strands 10 that hang down, and may be formed in a number corresponding to the number of the nozzles on the side wall suspending from the upper surface of the upper flap 4a. A single sheet may be formed by forming a square, triangular, or U-shaped narrow groove in a number of sections corresponding to the number of nozzles.
The upper flap 4a is attached so as to be able to turn back and forth around a support shaft (not shown), and the strand 10 is prevented from sticking to the upper flap 4a and peeled off to smoothly move the strand 10 downstream. It can be moved.

In addition, cooling water for cooling the strand 10 and feeding the strand 10 into the rectifying guide 4b flows into the plurality of channels from the slit-shaped cooling water outlet 12a. This cooling water is supplied to the cooling water tank 12 fixed to the back surface of the upper flap via the cooling water inlet 12b, and the amount of water that can at least solidify the outer surface of the strand 10 is secured. It is necessary to
Further, the strand 10 suspended from the nozzle 3 to the channel of the upper flap 4a is bent to approximately 70 to 90 degrees in the channel of the upper flap 4a by the water flow of the cooling water flowing from the cooling water outlet 12a, and sent to the rectifying guide 4b. It is.

Furthermore, it is also possible to inject cooling water from a plurality of cooling sprays 13 disposed above the inclined trough 4 immediately after the strand 10 is suspended by the upper flap 4b and bent by the water flow of the cooling water. The strand 10 is preferably cooled and solidified, and the strand 10 can be quickly submerged in the channels disposed in the upper flap 4a and the rectifying guide 4b by the water pressure.
The cooling spray 13 is disposed at a constant pitch apart from the surface of the inclined trough 4 at a fixed interval, but the arrangement range may extend over the entire inclined trough 4 from the upper flap 4a to the lower flap 4c, or Only the rectifying guide 4b may be used.

As described above and as shown in FIG. 1, after the strand 10 reaches the upper end of the upper flap 4a, it flows down while being cooled by the cooling water in the channel of the upper flap 4a. The amount of cooling water in the channel at this time Is adjusted so that the individual strands 10 do not jump out of one channel and move to another channel and stick to each other even when the specific gravity of the strand 10 is small and the strand 10 floats in the cooling water. There must be.
The channel should have a sufficient width so that the strand 10 does not contact the side surface of the channel until at least the surface of the strand 10 is solidified and does not stick to the side surface of the channel.

The flow rate of the cooling water flowing out from the cooling water outlet 12a at the upper end of the upper flap 4a is adjusted to 0.35 to 5 m / sec, preferably 0.5 to 2 m / sec.
If the flow rate of the cooling water is slower than 0.32 m / sec, the difference from the moving speed of the strand 10 when the strand 10 is pushed out becomes small, the cooling effect is small, and the strand 10 is conveyed downstream by the cooling water. The conveyance force is also reduced, and the probability that the strand 10 can be transferred to the take-up roller 7 is likely to decrease.
On the contrary, if the flow rate of the cooling water is faster than 5 m / sec, the difference with the moving speed of the strands 10 when the strands 10 are pushed out increases, and although the cooling effect is large, the strands 10 are conveyed downstream by the cooling water. The conveying force to be increased is increased, and the base portion of the strand 10 of the thermoplastic resin pushed out from the nozzle 3 is pulled, so that the diameter of the strand 10 becomes smaller than the diameter of the nozzle 3 or excessive cooling water causes the floating force of the strand 10 to increase. In addition, there is a possibility that the strands 10 jump out of one channel and move to another channel and stick to each other.

On the downstream side of the upper flap 4a, a rectifying guide 4b having a channel engraved in a state extending from the upper flap 4a is disposed so as to be able to reciprocate in the left-right direction. A lower flap 4c is disposed at the lower end of the rectifying guide 4b.
Similar to the upper flap 4a, the lower flap 4c is configured to be rotatable in the front-rear direction by a support shaft (not shown) provided in the upper end region of the lower flap 4c. This is opposed to the take-up roller 7 when a situation occurs in which the strands 10 are accumulated and stacked in a pole shape at the front part of the pair of take-up rollers 7 disposed on the downstream side of the lower flap 4c. The end of the lower flap 4c is pressed by the strand 10 and pivots backward so that the lower flap 4c can be pulled away from the strand 10 so that the strands stacked on the pole can be removed without causing danger to the operator. It is.

The take-up roller 7 disposed on the downstream side of the lower flap 4c is composed of two rollers 7a and 7b having different diameters disposed on the upper and lower sides, and both are connected to the same drive source and have the same rotational speed. It is driven by. For this reason, the circumferential speed of the two rollers 7a and 7b is faster by the larger diameter of the large-diameter roller 7a disposed in the upper portion than the small-diameter roller 7b disposed in the lower portion, and the strand 10 The take-up roller 7 can be smoothly supplied.
Note that the outer periphery of the take-up roller 7 may be formed so that both the upper and lower rollers 7a and 7b are smooth, or the outer periphery of the large-diameter roller 7a is provided with a plurality of fine grooves parallel to the shaft center to form the strand 10. The take-up roller 7 may be reliably taken in. Furthermore, the large-diameter roller 7a may have a plurality of spiral irregularities formed on the outer periphery thereof.

  In the take-up roller 7, since the peripheral speeds of the upper and lower rollers 7a and 7b are different as described above, the sliding friction between the upper and lower rollers 7a and 7b and the strand 10 is large on the upper roller 7a side having a large diameter. 10 is bent slightly upward along the outer periphery of the upper roller 7a and faces the rotary blade 8a of the cutter 8 that rotates counterclockwise, so that the strand 10 can be easily cut. .

The strand 10 taken together with the cooling water by the take-up roller 7 is sent to the downstream cutter 8 while being held and taken up by the take-up roller 7, and has a desired shape and dimension by the rotary blade 8 a and the fixed blade 9 of the cutter 8. It cut | disconnects to the thermoplastic resin granular material 11 which it had.
The cutter 8 is disposed so as to extend across the strand 10 in a region separated from the take-up roller 7, and has a constant twist angle with respect to the axial center of the cutter 8 on the outer periphery thereof. A so-called spiral rotary blade 8a is mounted.
On the other hand, a fixed blade 9 is mounted on the lower roller 7 b side of the take-up roller 7 so as to face the cutter 8. The fixed blade 9 is a straight blade parallel to the axial direction, and the strand 10 is cut with the rotary blade 8a of the cutter 8 disposed slightly apart to obtain a thermoplastic resin granular material 11. Yes.
In the thermoplastic resin granule manufacturing apparatus of the present invention, the narrow groove 9a for preventing the side slip of the strand 10 is formed on the upper surface of the fixed blade 9 with a depth of 0.3 mm to 0.7 mm and an adjacent interval of 0.7 mm to 1.5 mm. A plurality of them are provided (see FIGS. 2 and 3).

The cut thermoplastic resin granules 10 are dried and cooled in a subsequent process (not shown) and then packed.
Further, the cooling water used for cooling and flowing down the strand 10 is separated from the thermoplastic resin particulates 11 at the lower end of the inclined trough 4, for example, downstream of the cutter 8, and if necessary, impurities are passed through the filter. After being removed, it is returned to the cooling water tank 12 fixed to the back surface of the upper flap 4a by a pump and reused.

The present invention repeats the reciprocating movement of the flow straightening guide 4b and the lower flap 4c of the inclined trough 4 using the thermoplastic resin granular material manufacturing apparatus 1 having the above-described structure and action, and the strand 10 generated along with the reciprocating movement. Side slip on the upper surface of the fixed blade 9 is prevented by a plurality of fine grooves 9a carved on the upper surface of the fixed blade 9, and a thermoplastic resin granular material 11 having a desired shape and dimension is obtained. 2 and FIG. In the figure, reference numeral 5 denotes a traverse guide, which shows a portion that reciprocates in the above-described inclined trough 4, that is, a combination of the straightening guide 4b and the lower flap 4c.
The reciprocating means 6 for reciprocating the straightening guide 4b and the lower flap 4c of the inclined trough 4 is any known means such as a cam mechanism, a screw mechanism, or a linear motor that converts the rotational motion of the electric motor into linear motion. As long as it can achieve its purpose, such as a power source capable of reciprocating, the structure and operation of preventing the side slip of the strand 10 on the upper surface of the fixed blade 9 will be described below.

As shown in FIG. 2, a guide 5 a is provided at the lower end of the traverse guide 5 for delivering the strand 10 to the take-up roller 7 at a constant interval.
In addition, a plurality of spiral irregularities are formed on the outer periphery of the large-diameter roller 7 a of the take-up roller 7, and the strand 10 that reciprocates between the convex portion and the small-diameter roller 7 b is always held between the cutter 8 It can be sent stably.

As shown in FIG. 3, the fixed blade 9 disposed through the space of the take-up roller 7 has a depth of 0.3 mm to 0.7 mm on its upper surface and a plurality of adjacent intervals of 0.7 mm to 1.5 mm. The narrow groove 9a is engraved. In FIG. 3, the cross section of the narrow groove 9a is shown as a triangle. However, the cross section is not limited to this, and the narrow groove 9a may have a quadrangular or U-shaped cross section.
Since the narrow groove 9a is formed on the upper surface of the fixed blade 9, the strand 10 is pressed against the cutting edge of the fixed blade 9 by the pressure applied by the rotary blade 8a to cut the strand 10. A static frictional force is generated between the narrow groove 9a carved on the upper surface and the strand 10, and the rotary blade 8a has a spiral shape with an angle of 1 degree to 4 degrees with respect to the rotation axis. Even when the generated strand overcomes the force of side-sliding along the upper surface of the fixed blade 9 and the moving direction of the strand 10 coincides with the moving direction of the rotary blade 8a, the side-sliding of the strand does not occur and the strand is vertical. It is cut and its cross section is not slanted.
Then, until the rotary blade 8a cuts the strand 10 and then comes into contact with the strand 10, the pressure from the rotary blade 8a is not applied to the strand 10, so the static friction between the strand 10 and the upper surface of the fixed blade 9 The reciprocating movement of the strand 10 is not impaired, and therefore the cutting of the entire surface of the rotary blade 8a is possible, the generation of groove marks on the fixed blade 9 is prevented, and the life of the cutter 8 can be extended.

Structure explanatory drawing of the thermoplastic resin granular material manufacturing apparatus of the present invention Detailed explanation of traverse guide and cutter part Perspective view of an embodiment of a fixed blade Partial structure diagram of a conventional thermoplastic resin particle production equipment Enlarged view of groove marks due to cutter wear Partial structural diagram of an example of a conventional thermoplastic resin particle production apparatus provided with a reciprocating means for strands

Explanation of symbols

1: Production apparatus for thermoplastic resin granules 2: Die head 3: Nozzle 4: Inclined trough 4a: Upper flap 4b: Straightening guide 4c: Lower flap 5: Traverse guide 5a: Guide 6: Reciprocating means 7: Take-up roller 7a: Large diameter (upper) roller 7b: Small diameter (lower) roller 8: Cutter 8a: Rotating blade 9: Fixed blade 9a: Fine groove 10: Strand 11: Granular material 12: Cooling water tank 12a: Cooling water outlet 12b: Cooling water inlet 13: Cooling water spray 30: Thermoplastic resin granular material production apparatus 34: Inclined trough 34b: Straightening guide 34c: Lower trough 36: Reciprocating motion means 37: Take-up roller 38: Cutter 39: Fixed blade 50 : Production apparatus for thermoplastic resin granules 54: Inclined trough 57: Take-off roller 58: Cutter 59: Fixed blade 60: Groove mark

Claims (2)

After a plurality of thermoplastic resin strands are formed by continuously discharging molten thermoplastic resin from a plurality of nozzles and flowing together with cooling water to an inclined trough disposed below the nozzles, the desired length is obtained. In the thermoplastic resin granule manufacturing apparatus for cutting into chips, a traverse guide that repeatedly reciprocates a part of the upper surface of a cutter vicinity of the inclined trough in a direction perpendicular to the flow direction of the strand, and a blade edge Ri Na and and a cutter having a fixed blade having a number of fine grooves that are engraved in parallel to the running direction of the strands on the upper surface, and the narrow groove of the cutting edge the upper surface of the fixed blade, depth 0. An apparatus for producing a thermoplastic resin granular material, characterized in that it is 3 mm to 0.7 mm, and the interval between adjacent narrow grooves is 0.7 mm to 1.5 mm . After a plurality of thermoplastic resin strands are formed by continuously discharging molten thermoplastic resin from a plurality of nozzles and flowing together with cooling water to an inclined trough disposed below the nozzles, the desired length is obtained. In the thermoplastic resin granule manufacturing apparatus for cutting into chips, a traverse guide that repeatedly reciprocates a part of the upper surface of a cutter vicinity of the inclined trough in a direction perpendicular to the flow direction of the strand, and a blade edge A cutter provided with a fixed blade having a large number of fine grooves engraved on the upper surface in parallel with the running direction of the strand, and the traverse guide has a moving speed of 0.03 mm / s to 0.003 mm. / in s, all SANYO travel distance repeated reciprocation of 5 to 15 mm, also the narrow groove of the cutting edge the upper surface of the stationary blade, a depth 0.3 mm to 0.7 mm, Apparatus for producing a thermoplastic resin granulate interval between striations contact is characterized in that it is a 0.7Mm～1.5Mm.

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