JP2009006606A - Rubber extrusion device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a gear pump type rubber extrusion device with feed roll, capable of significantly increasing the discharge quantity of rubber. <P>SOLUTION: In the gear pump type rubber extrusion device 1, a casing 2 includes, in a cross section orthogonal to second-stage gears 11 and 12, a hollow part 40 defined by a boundary line including a first circular arc 13A concentric with the second-stage gear 11 to be meshed with a first-stage gear 21A, a second circular arc 14A concentric with the second-stage gear 12 not to be meshed with the first-stage gear 21A, a third circular arc 15A concentric with the first-stage gear 21A, and a fourth circular arc 16A concentric with a flat roll 22A. The hollow part 40 includes a dent part 5A formed by cutting out a casing part including an intersection between the second circular arc 14A and the fourth circular arc 16A. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention comprises a pair of gears that rotate in mesh with each other in a casing, a gear pump that pushes out rubber, and a pair of rolls that face each other across a small gap and rotate in opposite directions, and rubber material A feed roll that feeds the gear pump through the gap, a pair of gears as rear gears, a front gear that meshes with one of the rear gears, and the front gear across the gap. Flat rolls rotating in the opposite direction to the front gear are respectively arranged on a pair of mutually parallel axes, and plasticizing means for plasticizing the material supplied by the feed roll and conveying it to the gear pump The present invention relates to a provided rubber extrusion device.

  As a method for affixing the rubber member to the outside of the already formed tire component, a method of winding a continuous rubber ribbon having a certain cross section a plurality of times to finish it into a predetermined cross-sectional shape is used. As a rubber extruding apparatus for continuously extruding such a rubber ribbon, a gear pump is known which is composed of a pair of gears which mesh with each other and rotate.

  With regard to the supply of rubber to such a gear pump, conventionally, a means for extruding while plasticizing rubber with a screw has been used. However, such a supply method using a screw has a variation in rubber material or temperature. If it fluctuates, the viscoelastic characteristics of the rubber will change, and as a result, the amount of rubber supplied from the screw to the gear pump will fluctuate, and the amount of rubber discharged from the gear pump will not be constant. This is a problem, and causes a problem that the rubber ribbon extruded from the gear pump changes in cross section, making it impossible to form a rubber member having a uniform cross section.

  On the other hand, a method of supplying rubber using a feed roll is also known. However, since the ability to plasticize rubber is low, fluctuations in the properties of the rubber material supplied to the feed roll directly affect the feed roll to the gear pump. The amount of rubber supplied changes, and in this case as well, the amount of rubber discharged from the gear pump is not constant.

  Therefore, between the gear pump and the feed roll, a plasticizing means comprising a gear meshing with the gear of the gear pump and a roller disposed opposite to the gear is arranged, thereby performing plasticization and stabilizing the quantity. There has been proposed an extrusion apparatus that measures conversion (for example, see Patent Document 1).

  FIG. 1 is a cross-sectional view showing such a conventional rubber extrusion apparatus, FIG. 2 is a cross-sectional view showing this apparatus in another cross section, and the rubber extrusion apparatus 1 includes an extrusion head 3 for discharging rubber G, The gear pump 10 is composed of a pair of rear gears 11 and 12 that rotate in mesh with each other, and a pair of rolls 31 and 32 that rotate in opposite directions opposite to each other with a gap 33 interposed therebetween. A feed roll 30 for supplying the rubber material M to the gear pump 10 through the gap 33, a front gear 21A meshing with the rear gear 11, and the front gear 21A facing the front gear 21A across the gap 23. A flat roll 22A that rotates in the reverse direction, a front gear 21B that meshes with the rear gear 12, and a flat that rotates opposite to the front gear 21B opposite to the front gear 21B with a gap 23 therebetween. Consists roll 22B, it constituted comprising a plasticizing means 20 for conveying the material supplied by the feed roll 30 to the gear pump 10 and plasticized.

  Here, the rear gears 11 and 12, the front gear 21 </ b> A, the flat roll 22 </ b> A, and the rolls 31 and 32 are arranged in a temperature-controlled casing 92.

  FIG. 3 is a front view showing the rear gears 11 and 12 constituting the gear pump 10 (corresponding to the arrows AA in FIG. 1), and these gears 11 and 12 are tooth profiles of a double helical gear (mountain gear). Make a shape.

  FIG. 4 is a front view showing the plasticizing means 20 (corresponding to the arrow BB in FIG. 1), and FIG. 5 is a front view of the gear corresponding to the arrow CC in FIG. The plasticizing means 20 includes a pair of parallel shafts 25 and 26, the front gears 21A and 21B having a helical gear (helical gear) tooth profile and a half gear width of the rear gears 11 and 12; The flat rolls 22A and 22B, which are half the width of 12 and are not provided with teeth on the peripheral surface, are attached. The front gear 21A and the flat roll 22B are attached to the shaft 25 side by side in the axial direction. The front gear 21B and the flat roll 21A are similarly mounted side by side in the axial direction, the front gear 21A and the flat roll 22A are opposed to each other, and the front gear 21B and the flat roll 22B are opposed to each other. Front gear 1A is a subsequent stage gear 11, front gear 21B to the subsequent stage gear 12 are arranged so that each mesh.

  The casing 92 is formed with a hollow portion 80 that houses the gear pump 10, the plasticizing means 20, and the feed roll 30, and provides a region that becomes a rubber flow path. The hollow portion 80 has the cross-sectional region shown in FIG. 1. The smell is concentric with the first arc 81A concentric with the rear gear 11 on the side meshing with the front gear 21A, with the second arc 82A concentric with the rear gear 12 on the side not meshing with the front gear 21A, and with the front gear 21A. The second stage arc 83A and the fourth stage arc 84A concentric with the flat roll 22A are separated by a boundary line, and in the cross-sectional area shown in FIG. 12, a second arc 82B concentric with the rear gear 11 on the side not meshing with the front gear 21B, a third arc 83B concentric with the front gear 21B, It is defined by the boundary line and a fourth arc 84B trawl 22B concentric.

  In the case of those shown in FIGS. 1 and 2, the first arc 81A and the second arc 82B form the same arc and form a part of a cylindrical surface continuous in the axial direction. A set of the arc 81B and the second arc 82A, a set of the third arc 83A and the fourth arc 84B, and a set of the third arc 83B and the fourth arc 84A are the same arc. As a result, a part of a cylindrical surface continuous in the axial direction is formed.

In the rubber extrusion device 90 configured as described above, the rubber material M supplied from the feed roll 30 passes through the first chamber 43 and is carried to the plasticizing means 20. The rubber G plasticized by the plasticizing means 20 and conveyed to the second chamber 44 is transferred to the third chamber by the gear pump 10, but the front gear 21 </ b> A and the rear gear 11 that mesh with each other. Of the rear stage gear 12 that moves along the arc surface 82A after passing between the flat roll 22A and the rear stage gear 12 because it cannot pass between the front stage gear 21B and the rear stage gear 12. The teeth of the rear gear 11 moving along the circular arc surface 82B after being passed between the flat roll 22B and the rear gear 11 after being accommodated between the teeth and transported to the third chamber 45. It can only be accommodated in between and transported to the third chamber 45, so that the discharge rate of the gear pump can be kept extremely low.
European Patent Application No. 1157604 (2001)

  The present invention has been made in view of such problems, and an object of the present invention is to provide a gear pump type rubber extrusion device with a feed roll that can greatly increase the amount of rubber discharged.

<1> consists of a pair of gears that rotate in mesh with each other in the casing, and consists of a gear pump that pushes rubber and a pair of rolls that face each other across a minute gap and rotate in opposite directions. A feed roll that supplies material to the gear pump through the gap, a pair of gears as rear gears, a front gear that meshes with one of these rear gears, and a gap between the front gear and the gap The flat rolls that face each other and rotate in the opposite direction to the front gear are arranged on a pair of mutually parallel axes, and the material supplied by the feed roll is plasticized and conveyed to the gear pump Means and
The casing has a first arc that is concentric with the rear gear that meshes with the front gear, and a second arc that is concentric with the rear gear that does not mesh with the front gear, in a cross section orthogonal to the rear gear. And a rubber extrusion device in which a hollow portion defined by a boundary line including a third arc concentric with the preceding gear and a fourth arc concentric with the flat roll is formed,
In the rubber extrusion device, a hollow portion formed by cutting out a casing portion including an intersection of the second arc and the fourth arc is provided in the hollow portion.

<2> is that in <1>, the number of the front gear and the flat roll provided in the plasticizing means is two, and the width of each of them is narrower than that of the rear gear. A front gear and a flat roll are arranged in the axial direction on each of the axis lines forming
The hollow portion is formed as a first hollow portion, and a hollow portion formed by cutting out a casing portion including an intersection of the first arc and the third arc is provided in the hollow portion, and arranged in the axial direction. It is a rubber extrusion apparatus which makes a 1st hollow part and a 2nd hollow part mutually communicate, and comprises a 2nd hollow part narrower than a 1st hollow part.

  <3> is a rubber extruding device in which the second dent portion is connected to the first dent portion so that the width thereof continuously changes in <2>.

  <4> In any one of <1> to <3>, in the cross section orthogonal to the rear stage gear, the width of the first depression is gradually increased from the fourth arc toward the second arc. After that, the rubber extruding device is configured to gradually decrease.

  According to <1>, since the hollow portion is provided with the hollow portion formed by cutting out the casing portion including the intersection of the second arc and the fourth arc, the hollow portion passes through the hollow portion. Thus, rubber can be supplied between the rear gear and the first arc surface, and the discharge amount of the gear pump can be greatly increased.

  According to <2>, the second dent formed by notching a casing portion including the intersection of the first arc and the third arc with the dent as the first dent. Since the first hollow portion arranged in the axial direction communicates with the second hollow portion, and the second hollow portion is configured to be narrower than the first hollow portion. The first circular arc surface in which the rubber that has entered the first depression is moved in the axial direction and moved to the second depression, and if there is no second depression, the rubber is hardly filled. And the half of the teeth in the axial direction of the rear gear can be filled with rubber, which can further increase the amount of rubber discharged.

  <3> According to <3>, since the 2nd hollow part was connected to the 1st hollow part so that the width | variety may change continuously, the rubber | gum from a 1st hollow part to a 2nd hollow part is used. It is possible to facilitate the movement in the axial direction, thereby increasing the rubber filling rate in the second depression and further increasing the amount of rubber discharged.

  According to <4>, in the cross section orthogonal to the rear gear, the width of the first recess is gradually increased and then gradually decreased from the fourth arc toward the second arc. Smooth rubber filling of the rear gear can be ensured while preventing the rubber from being caught in the reverse direction of discharge in the gear.

  FIG. 1 is a cross-sectional view showing a rubber extrusion device according to an embodiment of the present invention, FIG. 2 is a partial cross-sectional view showing this device in another cross section, and the rubber extrusion device 1 is an extrusion head for discharging rubber G 3 and a pair of rear gears 11 and 12 that mesh with each other and rotate, and a gear pump 10 that discharges the rubber G to the extrusion head 3 and a pair of rolls that face each other across the gap 33 and rotate in opposite directions. 31 and 32, and a feed roll 30 that supplies the rubber material M to the gear pump 10 through the gap 33, a front gear 21A that meshes with one of the rear gears 11 and 12, and the front gear 21A. And a flat roll 22A that rotates in the opposite direction to the front gear 21A, a front gear 21B that meshes with the other gear 12, and a front gear 21B that faces the front gear 21B. It comprises a flat roll 22B that rotates in the opposite direction to the front gear 21B, and comprises plasticizing means 20 that plasticizes the material supplied by the feed roll 30 and conveys it to the gear pump 10.

  Here, the rear gears 11 and 12, the front gear 21 </ b> A, the flat roll 22 </ b> A, and the rolls 31 and 32 are arranged in the temperature-controlled casing 2.

  The rear gears 11 and 12 constituting the gear pump 10 preferably have a tooth shape of a double helical gear (mountain gear) (corresponding to the arrow AA in FIG. 6) as shown in a front view in FIG. The rubber can be continuously discharged by making it helical, the pulsation of the mass of the rubber ribbon R discharged from the extrusion head 3 is suppressed, and the rubber is left and right by making the teeth double. It is possible to flow symmetrically and maintain the uniformity of the rubber ribbon R in the width direction.

  The plasticizing means 20 has a pair of parallel shafts 25 as shown in FIG. 4 (corresponding to the arrow BB in FIG. 1) and FIG. 5 (corresponding to the arrow CC in FIG. 6). 26, the front gears 21A and 21B having half the width of the rear gears 11 and 12 and the helical gears (helical gears) and the half width of the rear gears 11 and 12 and teeth on the peripheral surface. Flat rolls 22A and 22B that are not provided are attached, the shaft 25 has the front gear 21A and the flat roll 22B aligned in the axial direction, and the shaft 26 has the front gear 21B and the flat roll 21A in the same manner. The front gear 21A and the flat roll 22A are opposed to each other, the front gear 21B and the flat roll 22B are opposed to each other, the front gear 21A is opposed to the rear gear 11, and the front gear 21B is rear gear 12. In It is arranged so as to mesh with each.

  6 shows a cross section corresponding to the arrow DD in FIG. 5, and FIG. 7 shows a cross section corresponding to the arrow EE in FIG.

  FIG. 8 is a conceptual diagram showing the casing 2 (however, the peripheral portion of the feed roll 30 is omitted) and the plasticizing means 20 in a disassembled state in perspective, and the shape of the hollow portion 40 of the casing 2 is shown in FIG. Referring also to FIG. 7, the hollow portion 40 of the casing 2 is concentric with the rear gear 11 on the side meshing with the front gear 21 </ b> A in a first cross section (cross section shown in FIG. 6) orthogonal to the rear gears 11 and 12. The first arc 13A, the second arc 14A concentric with the rear gear 12 on the side not meshing with the front gear 11, the third arc 15A concentric with the front gear 21A, and the fourth arc concentric with the flat roll 22A. The first cross-section is concentric with the rear-stage gear 12 on the side meshing with the front-stage gear 21B in the second cross-section (the cross section shown in FIG. 7) orthogonal to the rear-stage gears 11 and 12 at the same time. Arc 1 B, a second arc 14B concentric with the rear gear 11 on the side not meshed with the front gear 21B, a third arc 15B concentric with the front gear 21B, and a fourth arc 16B concentric with the flat roll 22B. It is defined by a boundary line including it.

  Here, the first circular arc surface 13A in the first cross section and the second circular arc surface 14B in the second cross section form a part of a cylindrical surface continuous in the length direction. Similarly, the second circular arc surface 14A and the first arc surface 13B are the third arc surface 15A and the fourth arc surface 16B, and the fourth arc surface 16A and the third arc surface 15B are the group. Each form part of a continuous cylindrical surface.

In the first cross section, the rubber extrusion device 1 according to the present invention cuts out a casing portion including the intersection point P ₁ between the second arc 14A and the fourth arc 16A to form a recess 5A. to have a second arc 14B, characterized in that to form devoid recess 5B off the casing part including the intersection P ₂ of the fourth arc 16B.

Further, the rubber extruder 1 is first preferably, recess 5A, and 5B as the first recess portion, by cutting a first circular arc 13A, a casing part including the intersection to Q ₁ and the third arc 15A the second recess 6A is formed, similarly, the first circular arc 13B, both a cut away the casing part including the intersection Q ₂ and the third arc 15B forming the second recess portion 6B, the axis 25 , 26 and the first dent part 5A and the second dent part 6B arranged in parallel with each other, and the first dent part 5B and the second dent part 6A are communicated with each other. The recesses 6A and 6B are configured to be narrower than the first recesses 5A and 5B.

  In the rubber extrusion device 1 configured as described above, in order to push out the rubber ribbon R, first, the gears 11, 12, 21A, 21B and the flat rolls 22B, 22A constituting the gear pump 10 and the plasticizing means 20 are moved. The rolls 31 and 32 constituting the feed roll 30 are rotated at a rotation speed independent of the gears 11, 12, 21 </ b> A and 21 </ b> B, and the rubber material M is fed into the feed roll 30. Is continuously supplied to the bank 42 formed between the rolls 31 and 32.

  The rubber material M supplied to the bank 42 moves to the first chamber 43 through the gap between them by the rotation of the rolls 31 and 32. The rubber material M is conveyed to the second chamber 44 by the front gears 21A and 21B and the flat rolls 22A and 22B of the plasticizing means 20, and becomes a plasticized rubber G.

  As shown in FIG. 8, the rear gears 11 and 12 constituting the gear pump 10 have mutual teeth in the third chamber 45 as shown in the detailed view showing the vicinity of the meshing point 18 of the gears 11 and 12. 46 is approaching and after the meshing point 18 where these teeth 46 are engaged, the teeth 46 are rotated in the second chamber 44 so that they are separated from each other. 18 in the direction of approaching the arcuate surfaces 13A, 13B, 14A, and 14B, accommodated in the interdental space 47 between the teeth 46 and the teeth 46 adjacent to each other, which are emptied after 18 Carried.

  However, the rubber G housed in the inter-tooth space 47 on the half width side that meshes with the gear 21A of the gear 11 cannot advance beyond the meshing point 28 between the gear 11 and the gear 21A. The rubber G housed in the inter-tooth space 47 on the half-width side that meshes with the gear 21B of the gear 12 cannot advance beyond the meshing point 29 of the gear 12 with the gear 21B. , 12 of the rubber G accommodated in the interdental space 47, the half-width side facing the flat rolls 22A, 22B (the half-width side facing the flat roll 22A of the gear 12 in FIG. 1 and the gear in FIG. 11 is accommodated in the third chamber 45 only on the half-width side facing the 11 flat rolls 22B.

  Since a sufficient discharge amount cannot be obtained with this alone, the present invention addresses this problem by providing the first recesses 5A, 5B. By providing these recesses 5A, 5B, The rubber G moving together with the peripheral surfaces of the rolls 22A and 22B can also be pushed into the interdental space 47, and the density in the interdental space 47 can be increased to increase the discharge amount.

  More preferably, the second depression 6B is formed continuously with the first depression 5A, so that the rubber G pushed into the first depression 5A is diverted to the second depression 6B. The space between the first arcuate surface 13B and the rear gear 12 is also filled with rubber G, and similarly, the second recess 6A is formed continuously with the first recess 5B. The rubber G pushed into the first recess 5B is diverted into the second recess 6A, and the space between the first arcuate surface 13A and the rear gear 11 is filled and discharged. And the discharge amount can be greatly increased.

  It is preferable that the width of the first recesses 5A and 5B is gradually increased and then gradually decreased from the fourth arcs 16A and 16B toward the second arcs 14A and 14B. Further, when the first depressions 5A, 5B and the second depressions 6B, 6A are communicated with each other, it is preferable that their widths are continuously changed. The flow from the recesses 5A, 5B to the second recesses 6B, 6A can be made smooth, and the flow rate can be increased.

  Further, as a method of increasing the discharge amount of the rubber extruder, there is a method of increasing the fluidity of rubber by raising the temperature control temperature of the feed roll 30 in addition to providing the hollow portion. Conventionally, the temperature adjusting means of the rubber extruder includes a first temperature adjusting zone for adjusting the temperature of the extrusion head 3, and a second temperature adjusting zone for adjusting the temperature of the gear pump 10, the plasticizing means 20, and the entire feed roll 30. Are divided into two zones, and each of them is configured to be capable of independent temperature control. However, in the method proposed here, the second temperature control zone is further divided into a zone of the gear pump 10 and the plasticizing means 20, and a feed roll. By dividing the zone of the feed roll 30 into 30 zones, the zone of the feed roll 30 can be controlled at a temperature independent from the zone of the gear pump 10 and the plasticizing means 20, and the temperature control temperature of the feed roll 30 is Even when a low-temperature rubber material is supplied to the feed roll 30, it is set high so that it can be heated sufficiently, thereby increasing the fluidity of the rubber and increasing the discharge amount. It is possible.

  Embodiments differing from the conventional example only in that the conventional rubber extrusion device shown in FIGS. 1 and 2 is a conventional example, and the first and second depressions shown in FIGS. 6 and 7 are added. Using these rubber extruding devices as examples, the rubber extruding amounts of these rubber extruding devices with respect to the rotational speed of the gear pump were measured. The results are shown in FIG. As is apparent from FIG. 10, it can be seen that the rubber discharge amount of the embodiment is greatly increased compared to the conventional example.

It is sectional drawing of the conventional rubber extrusion apparatus. It is sectional drawing which shows the conventional rubber extrusion apparatus in another cross section. It is a front view which shows a front | former stage gear. It is a front view which shows a back | latter stage gear and a flat roll. It is an arrow view corresponding to CC arrow view of FIG. It is sectional drawing which shows the rubber extrusion apparatus of embodiment which concerns on this invention. It is sectional drawing in another cross section which shows the rubber extrusion apparatus of embodiment. It is a conceptual diagram which shows a casing and a plasticizing means. It is detail drawing showing the meshing point vicinity of a back | latter stage gear. It is a graph which shows the relationship between the rubber discharge amount and the gear pump rotation speed of the rubber extrusion apparatus of an Example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Rubber extrusion apparatus 2 Casing 3 Extrusion head 10 Gear pump 11, 12 Rear gear 13A, 13B 1st circular arc (surface)
14A, 14B Second arc (surface)
15A, 15B Third arc (surface)
16A, 16B Fourth arc (surface)
18 Meshing point between the rear gears 20 Plasticizing means 21A, 21B Front gears 22A, 22B Flat rolls 23 Clearance 25, 26 Shafts of the plasticizing means 28, 29 Meshing points between the front gears and the rear gears 30 Feed rolls 31, 32 rolls 42 Bank 43 First chamber 44 Second chamber 45 Third chamber 46 Gear teeth 47 Interdental space G Rubber M Rubber material R Rubber ribbon

Claims (4)

In the casing,
A pair of gears that mesh with each other and rotate, and a gear pump that pushes out rubber,
A pair of rolls facing each other across a minute gap and rotating in the opposite direction, a feed roll that feeds the rubber material through the gap to the gear pump;
The pair of gears are used as rear gears, a front gear that meshes with one of these rear gears, and a flat roll that faces the front gear across a gap and rotates in the opposite direction to the front gear. And a plasticizing means for plasticizing the material supplied by the feed roll and transporting the material to the gear pump.
The casing has a first arc that is concentric with the rear gear that meshes with the front gear, and a second arc that is concentric with the rear gear that does not mesh with the front gear, in a cross section orthogonal to the rear gear. And a rubber extrusion device in which a hollow portion defined by a boundary line including a third arc concentric with the preceding gear and a fourth arc concentric with the flat roll is formed,
A rubber extruding apparatus, wherein a hollow portion formed by cutting out a casing portion including an intersection of the second arc and the fourth arc is provided in the hollow portion. The number of the front gears and flat rolls provided in the plasticizing means is two, and the width of each of them is narrower than that of the rear gears. Rolls are arranged one by one in the axial direction,
The hollow portion is formed as a first hollow portion, and a hollow portion formed by cutting out a casing portion including an intersection of the first arc and the third arc is provided in the hollow portion, and arranged in the axial direction. The rubber extrusion device according to claim 1, wherein the first depression and the second depression are communicated with each other, and the second depression is configured to be narrower than the first depression.   The rubber extruding device according to claim 2, wherein the second indented portion is communicated with the first indented portion so that the width thereof continuously changes.   4. The structure according to claim 1, wherein, in a cross section orthogonal to the rear gear, the width of the first depression is gradually increased and then gradually decreased from the fourth arc toward the second arc. The rubber extrusion apparatus described in 1.