JP5121492B2 - Elastic roller manufacturing apparatus and elastic roller manufacturing method - Google Patents

Description

  The present invention relates to an elastic roller manufacturing apparatus and an elastic roller manufacturing method.

  Many of the rollers such as a charging roller and a developing roller used in an electrophotographic apparatus are provided with an elastic layer including a shaft body and rubber or elastomer covering its periphery (hereinafter also referred to as an elastic roller). One common method for manufacturing such an elastic roller is a method using a crosshead.

  That is, the shaft core is introduced into the cross head, the periphery of the shaft core is covered with unvulcanized rubber, and after curing, the outer diameter is adjusted by polishing or the like. According to this method, a highly accurate elastic roller can be manufactured with high productivity (Patent Document 1).

In this method, there has been reported a conveying apparatus configured to be able to continuously introduce an axial core body into a cross head using a plurality of pairs of feed rollers (Patent Document 2).
Japanese Patent Laid-Open No. 2003-300279 JP 2005-227754 A

  According to the study by the present inventors, the conveyance accuracy of the shaft core body to the cross head by the feed roller has an influence on the uniformity of the layer thickness of the raw material mixture of the elastic layer covering the periphery of the shaft core body. I found out that The uniformity of the thickness of the layer of the raw material mixture formed around the shaft core is important for obtaining a high-quality elastic roller with little eccentricity.

  An object of the present invention is to provide an elastic roller manufacturing apparatus and an elastic roller manufacturing method capable of efficiently manufacturing a high-quality elastic roller as a result of high accuracy of conveying the shaft core body to the cross head. It is in.

Apparatus for producing an elastic roller according to the present invention is directed to an apparatus for producing elastic roller around the mandrel is coated with an elastic layer, and the crosshead, sequentially for transporting said mandrel to said crosshead Of the plurality of pairs of feed rollers, the pair of feed rollers disposed at the position farthest from the cross head is made of resin or rubber around the cored bar. The at least one other pair of feed rollers comprises a second pair of rollers having a metal layer around the mandrel, and a second pair of feed rollers. The pressing force of the shaft core body by the pair of rollers is larger than the pressing force of the shaft core body by the pair of first rollers.

  A method of manufacturing an elastic roller according to the present invention is a method of manufacturing an elastic roller in which the periphery of the shaft core is covered with an elastic layer using the elastic roller manufacturing apparatus. A first step of transporting the core body to the crosshead, and a second step of covering the periphery of the shaft core body with a layer made of the material of the elastic layer in the crosshead, the first step comprising: It includes a step of transporting a plurality of shaft core bodies toward the cross head so that the front end of the subsequent shaft core body is always in contact with the rear end of the preceding shaft core body.

  According to the present invention, since the shaft core body can be introduced into the crosshead with higher accuracy, the thickness of the elastic layer covering the periphery of the shaft core body can be made uniform. As a result, a high-quality elastic roller can be obtained.

  An apparatus for manufacturing an elastic roller according to the present invention is an apparatus for manufacturing an elastic roller in which a shaft core is covered with an elastic layer, and includes a cross head and a plurality of pairs of feed rollers for sequentially transporting the cross head to the cross head. It has.

An example of the manufacturing apparatus of the elastic roller of this invention is shown in the schematic of FIG. 1A is a front view, and FIG. 1B is a side view. As shown in FIG. 1, the elastic roller manufacturing apparatus includes a transport unit 14, a crosshead 11, and an extruder 10 connected to the crosshead 11.
[Transport unit]
As shown in FIG. 2, the transport unit 14 has a plurality of pairs of feed rollers (25-1, 25-2, 25-3, 25-4) arranged in parallel. Can be sequentially conveyed to the crosshead 11. FIG. 2A is a plan view of the transport unit 14 as viewed from above. FIG.2 (b) is sectional drawing in the AA line of Fig.2 (a). In FIG. 2, one of the rollers (four rollers) constituting a plurality of pairs of feed rollers (25-1, 25-2, 25-3, 25-4) is fixed rotatably. It is a block. 28b is a block in which the other roller (four rollers) is rotatably fixed.

The feed roller supported by the block 28 a is rotatable by transmitting the rotation of the motor 30 via a belt 29 suspended on a gear portion provided at the end of the core metal 26. Each feed roller that is pivotally supported by the other block 28 b is pressed against the fixed block 28 a by the pressure means 31, and the shaft core 12 is pressed by the other feed roller and the groove 27.・ Pinch. Then, it rotates following the rotation of one of the feed rollers to convey the shaft core body 12. As the pressurizing means 31, an air cylinder, a hydraulic cylinder, a coil spring, a leaf spring, a disc spring or the like is used. The block 28b is guided and moved by two guides 32 penetrating the blocks 28a and 28b via bushes. When the block 28b is pressed by the pressing means 31, the blocks 28a and 28b are arranged in parallel so that each pair of feed rollers can securely clamp the shaft core body 12.
[First roller pair]
In the transport unit 14, the pair of feed rollers (25-1) arranged at the positions farthest from the cross head are a core metal 26 and a layer containing resin or rubber around it as shown in FIG. 3. It is composed of a first pair of rollers having a coating layer 34. FIG. 3A is a plan view, and FIG. 3B is a cross-sectional view taken along the line AA in FIG.

  The core metal 26 may be made of metal, high hardness resin, or the like. However, it is preferable that it has a strength that is durable against the pressure for sandwiching the shaft core body, and that large deformation does not occur due to pressurization. Specifically, a steel material or stainless steel having an elastic modulus of 190,000 Mpa or more can be used. The shape of the feed roller core may be either a columnar shape or a cylindrical shape.

Examples of the resin and rubber contained in the coating layer 34 include the following.
Resin: Nylon, polyamide (PA), polyacetal (POM), polycarbonate (PC), modified polyphenylene ether m-PPE, modified PPE). Polybutylene terephthalate (PBT), polyethylene terephthalate (PET), cyclic polyolefin (COP). Polyphenylene sulfide (PPS), polysulfone (PSF), polyethersulfone (PES), amorphous polyarylate (PAR), liquid crystal polymer (LCP), polyetheretherketone (PEEK), polyamideimide (PAI). Polyethylene (PE), polypropylene (PP), polyvinyl chloride (PVC), polyvinylidene chloride, polystyrene (PS). Polyvinyl acetate (PVAc), polytetrafluoroethylene (PTFE), ABS resin (acrylonitrile butadiene styrene resin), acrylic resin (PMMA), etc.
Rubber: Natural rubber, butadiene rubber, styrene butadiene rubber (SBR), nitrile rubber, ethylene propylene rubber (EPDM), chloroprene rubber (CR), nitrile butadiene rubber (NBR), epichlorohydrin rubber. Butyl rubber, silicone rubber, urethane rubber, fluorine rubber, chlorine rubber, etc. Other elastomers can also be used. These can be used as one kind or in combination.

  The elastic modulus of the covering layer 34 is preferably 1000 to 5000 MPa. As for the elastic modulus value, in the case of resin, the bending elastic modulus shown in JISK6911 is used, and in the case of rubber, it is tested based on JISK6394, and the value of the elastic modulus stored at 23 degrees and the test frequency of 10 Hz is adopted. Can do.

  The covering layer 34 in the first roller may include a plurality of layers. Moreover, you may coat | cover the outer periphery of the coating layer 34 with plating, such as nickel and chromium. Further, the surface of the coating layer 34 may be subjected to nitriding treatment or the like.

When a surface layer such as the above-described plating layer is provided on the surface of the coating layer 34, when the thickness of the surface layer is 0.1 mm or less, this is omitted from the object, and formula (1) described later is applied. . When the film thickness exceeds 0.1 mm, and when the coating layer 34 is composed of a layer containing a plurality of rubbers or resins, when the shaft core body is sandwiched, the layer having the smallest elastic modulus is greatly deformed. Tend to occur. Therefore, in the calculation of the applied pressure described later, the film thickness and elastic modulus of the layer having the lowest elastic modulus are applied to the expression (1) described later. Further, an uneven surface having a surface roughness Rz (JIS94-B060) of about 1 to 10 μm by blasting or the like can be formed on the outer peripheral surface of the coating layer.
[Second roller pair]
In the transport unit 14, at least one pair of other feed rollers other than the pair of feed rollers disposed at the position farthest from the cross head is a core metal and a coating that is a metal layer provided around the core. And a second pair of rollers having a layer.

  Examples of the material of the metal layer include brass, aluminum, duralumin, titanium, and copper from the viewpoint of good transportability of the shaft core.

  The elastic modulus of the metal layer is preferably in the range of 70000 to 220,000 MPa from the viewpoint of the transportability of the shaft core. For the elastic modulus of the metal layer, a test piece made of the same material is subjected to a tensile test based on JIS Z2241, and the value of the ratio of stress and strain before starting to yield in the stress-strain diagram can be adopted.

  In the present invention, configuring the pair of feed rollers (25-4) arranged at the position closest to the cross head as the second roller pair further improves the conveyance accuracy of the shaft core body. Preferred above. In this case, the other pair of feed rollers (25-2, 25-3) may be constituted by either the first roller pair or the second roller pair.

The first row La及 beauty second roller stably hold the mandrel on the outer peripheral surface may have a groove 27 for transporting. The groove 27 preferably has an axisymmetric shape with respect to the central axis of the roller. Examples of the shape of the groove 27 include an arc shape slightly larger than the core diameter and a V shape. Moreover, you may have further a small groove | channel in the one part. Specific examples of the cross-sectional shape of the groove 27 are shown in FIGS.

The runout accuracy of the coating layer for each of the first roller and the second roller is preferably 0.05 mm or less. The roundness is preferably 0.02 mm or less. By making the runout accuracy and roundness within this range, the contact between the feed roller and the shaft core body becomes better. Moreover, it can suppress that a contact state with a shaft core body changes with rotation of a feed roller, and a core metal slips, and a shaft core body can be conveyed with higher precision. For this reason, the initial amount of rubber or elastomer can be supplied with high accuracy around the shaft core body in the cross head, and a more accurate elastic roller can be manufactured. The roundness can be measured using a roundness measuring device (for example, trade name: Round Test RA-2100A; manufactured by Mitutoyo Corporation).
[Pressure applied to the shaft core by the first roller pair and the second roller pair]
The pressing force of the shaft core body by the pair of second rollers is made larger than the pressing force of the shaft core body by the pair of first rollers. That is, the first pair of rollers easily holds the shaft core. On the other hand, the pair of second rollers can apply a high pressure to the shaft core, and can locally increase the frictional force and suppress slippage during conveyance.

In the transport unit 14 shown in FIG. 2, a plurality of pairs of feed rollers can be pressurized together. In the case of such a configuration, the pressure applied to the shaft core body by the pair of feed rollers can be changed by using at least one of the methods listed in the following (A) to (C).
(A) The blocks to which the feed rollers are fixed are inclined to each other.
(B) Change the fixing position of the feed roller as appropriate.
(C) Change the thickness of the feed roller as appropriate.

  As another aspect of the means for adjusting the pressure applied to the shaft core by the feed roller, a configuration in which a pressurizing mechanism is provided for each of a plurality of pairs of feed rollers may be employed.

  By the way, it is preferable to adjust the pressure applied by the first roller pair and the pressure applied by the second roller pair so as to satisfy the following relationship.

  That is, the thickness of the layer containing the resin or rubber of the first roller when the shaft core is not conveyed is T1a, and the thickness of the metal layer of the second roller is T2a.

  In addition, the thickness of the layer including the resin or rubber of the first roller when the shaft core is conveyed is T1b, and the thickness of the metal layer of the second roller is T2b.

  Further, the elastic modulus of the layer containing the resin or rubber of the first roller is Ea, and the elastic modulus of the metal layer of the second roller is Eb. Then, the pressing force of the shaft core body by the pair of the first roller and the pair of the second roller is adjusted so that these relationships satisfy Expression (1).

[(T1a−T1b) / T1a] · Ea <[(T2a−T2b) / T2a] · Eb (1)
In the formula (1), (T1a-T1b) represents the amount of displacement of the layer containing the resin or rubber of the first roller when the shaft core is sandwiched between the pair of first rollers. The value obtained by dividing this by (T1a) indicates the amount of deformation per unit thickness of the layer containing the resin or rubber. The product of the amount of deformation and the elastic modulus of the layer containing the resin or rubber approximately corresponds to the stress that the layer containing the resin or rubber of the first roller receives from the shaft core body due to the sandwiching of the shaft core body. . That is, it is a value corresponding to the pressure applied to the shaft core by the first roller.

  Similarly, [(T2a−T2b) / T2a] · Eb corresponds to the pressure applied to the shaft core by the second roller.

Here, the thickness (T1a, T1b) of the layer containing the resin or rubber of the first roller and the thickness (T2a and T2b) of the metal layer of the second roller will be described.
(2) When the first roller is composed of a cored bar and a layer containing resin or rubber, and no groove is formed on the outer peripheral surface;
T1a is the difference between the radius of the roller and the radius of the cored bar. T1b is the difference between the distance from the core center to the shaft core and the radius of the core when the shaft core is sandwiched.
(E) When the second roller is composed of a metal core and a metal layer, and no groove is formed on the outer peripheral surface;
T2a is the difference between the radius of the roller and the radius of the cored bar. T2b is the difference between the distance from the core center to the shaft core and the radius of the core when the shaft core is sandwiched.
(F) When the first roller is composed of a cored bar and a layer containing resin or rubber, and a groove for conveying the shaft core body is formed on the outer peripheral surface;
T1a is the distance from the position where the shaft core body and the layer containing resin or rubber are in contact to the interface between the layer containing resin or rubber and the cored bar. T1b is the distance from the position where the shaft core body and the layer containing resin or rubber are in contact to the interface between the layer containing resin or rubber and the cored bar.
(G) When the second roller is composed of a core metal and a metal layer, and a groove for conveying the shaft core body is formed on the outer peripheral surface;
T2a is the distance from the position where the shaft core body and the metal layer are in contact to the interface between the metal layer and the metal core. T2b is the distance from the position where the shaft core body and the metal layer are in contact to the interface between the metal layer and the metal core.

  In the cases (2) to (g), the measurement of T1a, T1b, T2a and T2b may be performed by measuring the actual thickness of each layer, or by measuring the distance between the axes of a pair of rollers and calculating it. You can also. At the time of measurement, the shaft core is held between all pairs of feed rollers. The inter-axis distance is a measured value measured between the outer surfaces of the cored bar of the feed roller using a caliper, a micrometer, or a non-contact laser length measuring instrument (for example, product name: LS-7030; manufactured by Keyence Corporation). Can be adopted.

  Using the first roller pair and the second roller pair, the pressure core is adjusted so as to satisfy the formula (1), and the shaft core body is sandwiched and conveyed, thereby further increasing the shaft core body. It can be conveyed to the crosshead with high accuracy and stability.

Moreover, if the supply amount of rubber or elastomer to the mandrel around the crosshead and fixed amount, to produce a roller crown shape, if the mandrel the outer diameter changes, the conveying speed of the mandrel The occurrence of slipping can be suppressed even when the speed is changed. Thus, coated with rubber or elastomer desired amount around the mandrel, it is possible to obtain a good outer diameter accuracy in rollers being extruded. As a result, post-extrusion post-processing can be omitted, and even when post-processing such as polishing is performed, the polishing allowance is reduced, and a roller with small variations in physical properties such as surface roughness and resistance can be obtained. .

  In the transport unit, it is preferable that a gap (39 in FIG. 2) between each pair of feed roller maximum diameter portions is 0.05 mm or more and 0.5 mm or less. Such a gap can suppress a rapid fluctuation in the interval between the feed rollers when the conveyance of the shaft core is interrupted, and can continue the conveyance of the shaft core more stably. The pair of feed rollers installed with a gap is preferably a pair of feed rollers made of metal rollers, particularly a pair of feed rollers (25-4) closest to the cross head. More preferably, all feed roller pairs are used. As a measurement method of this gap, a value measured using a gap gauge or a non-contact laser length measuring machine (LS-5120: manufactured by Keyence Corporation) can be used.

The feed roller has, for example, an outer diameter of 20 to 150 mm, a film thickness of 5 to 140 mm, and a thickness of about 5 to 30 mm when the length of the shaft core to be conveyed is 200 to 400 mm and the outer shape is about 4 to 10 mm. Can be mentioned. Moreover, the pitch arrange | positioned on the block of the said feed roller can mention about 1.05-2 times the outer diameter of a feed roller. As a conveyance speed of a shaft core object, it can be set as 10-100 mm / sec, for example.
[Crosshead]
The crosshead used in the elastic roller manufacturing apparatus of the present invention can be of a general configuration.

As shown in the configuration diagram of FIG. 5, the cross head is provided with a mandrel 22 having a circular hole portion for allowing the shaft core body 12 to pass through, and a neck portion 23 connected to the pushing portion 10. The raw material composition kneaded in the extruder 10 reaches the vicinity of the mandrel 22 through the neck portion 23, and is divided into two along the mandrel at the cylindrical receiving portion provided around the mandrel. And merge again to form a cylindrical shape. In the tapered nipple 20 provided at the lower end portion of the mandrel, the raw material composition is wound around the shaft core conveyed through the circular hole portion of the mandrel, and from the die 21 provided at the lower end of the cross head. The roller is pushed out. The die 21 includes four alignment bolts 15 arranged at a pitch of 90 degrees, as shown in a cross-sectional view taken along line AA in FIG. 5, with respect to the traveling direction of the shaft core body. and movable in the direction of the orthogonal biaxial, it can be finely adjust the center of the cylindrical material composition is formed mandrel and thereon.
[Extruder]
The extruder connected to the crosshead may include a temperature-controllable cylinder and screw, and may include a vent hole and a vacuum pump for removing bubbles contained therein.

  Although the crosshead shown in FIG. 5 is extruded in the vertical direction, the extruder may be configured to extrude in the horizontal direction. However, it is preferable to extrude in the vertical direction in terms of accuracy and the like.

  There is no restriction | limiting in particular as rubber | gum or an elastomer contained in the raw material mixture of an elastic layer supplied to the circumference | surroundings of a shaft core body in a crosshead. Specifically, the following can be exemplified. Natural rubber, butadiene rubber, styrene butadiene rubber (SBR), nitrile rubber, ethylene propylene rubber (EPDM), chloroprene rubber (CR), nitrile butadiene rubber (NBR), epichlorohydrin rubber, butyl rubber. Silicone rubber, urethane rubber, fluorine rubber, chlorine rubber, etc.

  The raw material mixture contains vulcanizing agents such as sulfur, metal oxides and organic oxides, inorganic fillers such as carbon black, talc and clay, other vulcanization accelerators and process oils as required. It may be.

As a conductive agent, carbons such as carbon black, metal oxides such as graphite, TiO ₂ , SnO ₂ and ZnO, solid solutions of SnO ₂ and Sb ₂ O ₅ , double oxides such as a solid solution of ZnO and Al ₂ O ₃ , Metal powder such as Cu and Ag, conductive fibers, and the like may be used. These conductive agents can be added in an amount of 5 to 200 parts by mass with respect to 100 parts by mass of rubber or elastomer.
[Other parts]
The elastic roller manufacturing apparatus shown in FIG. 1 further includes a shaft core body supply unit 13 that supplies a shaft core body, a cutting machine 16, a support mechanism 17, and the like.

Mandrel supply unit 13 includes a stocker 13a for accommodating a mandrel, and a delivery portion 13b is supplied to the conveying unit 14 takes out one mandrel from the stocker 13a.

The support mechanism 17 provided below the cross head 11 is a roller that is extruded from the cross head 11 while the outer periphery of the shaft core 12 that is transported without gaps is covered with unvulcanized rubber or elastomer in a cylindrical shape. Support. The support mechanism 17 moves the roller pushed out from the cross head in the vertical direction according to the moving speed.

The cutting machine 16 has a pair of semicircular cutting blades, and when the support mechanism 17 supporting the rollers reaches a predetermined position, the cutting blades are formed in a cylindrical shape around the shaft core. The raw material composition is cut. The cut roller is then placed on the tray 19 by the auto hand 18 to cure the unvulcanized rubber or elastomer, and if necessary, polish it to adjust the outer diameter and surface roughness, and apply ultraviolet rays, electron beams, The elastic roller is formed by a surface treatment process using plasma or the like.

  According to the elastic roller manufacturing method of the present invention, the shaft core body can be reliably sandwiched and transported by the pair of first rollers. On the other hand, the shaft core can be introduced into the cross head without slipping by the pair of second rollers. A pair of feed rollers constituted by a pair of first rollers is arranged at a position farthest from the cross head, and a pair of feed rollers constituted by a pair of second rollers is located close to the cross head, preferably a cross. Place it at the position closest to the head. For this reason, the shaft core can be transported to the crosshead stably and accurately.

The roller extrusion device of the present invention will be described in detail below, but the technical scope of the present invention is not limited thereto.
[Example 1]
As a raw material composition of a roller to be manufactured, the following components were first kneaded for 15 minutes by a pressure kneader.
NBR (trade name “JSR N230SV”: manufactured by JSR Corporation): 100 parts by mass;
Carbon black (trade name “Toka Black # 7360SB” manufactured by Tokai Carbon Co., Ltd.): 48 parts by mass;
Zinc stearate: 1 part by mass;
Zinc oxide: 5 parts by mass;
Calcium carbonate (trade name “Nanox # 30”: manufactured by Maruo Calcium Co., Ltd.): 20 parts by mass.

Next, the following components were added and kneaded with an open roll for 15 minutes.
Tetrabenzylthiuram disulfide (trade name “Parkasit TBzTD”: manufactured by Flexis Co., Ltd.): 4.5 parts by mass;
Sulfur (vulcanizing agent): 1 part by mass.

  A die having an inner diameter of 9 mm is set in the extrusion apparatus shown in FIG. 1, a vent type extruder having a diameter of 50 mm (L / D = 20) is used as the extruder, and the cylinder and screw of the extruder and the crosshead are set at 90 ° C. The temperature was adjusted.

  The shaft core was prepared by applying nickel plating to the outer peripheral surface of a stainless steel (SUM22L) cylinder having a diameter of 6 mm and a total length of 252 mm, and applying an adhesive to the region excluding both ends 10 mm. The adhesive used was a hot melt type having conductivity, and the film thickness was about 3 μm.

  As the transport unit, the apparatus shown in FIG. 2 was used. The pair of feed rollers (25-1, 25-2) forms a layer made of 27 mm thick nylon (MC-nylon MC901: manufactured by Nippon Polypenco Co., Ltd.) on a stainless steel (SUS304) core with an outer diameter of 25 mm. The first roller was used. In order to hold the shaft core, a semicircular cross-sectional groove shown in FIG. The pair of feed rollers (25-3, 25-4) was constituted by a roller (second roller) in which a layer made of brass having a thickness of 27 mm was formed on a stainless steel (SUS304) core metal having an outer diameter of 25 mm. Moreover, regarding each feed roller, the film thickness was changed, and the pressure applied to the shaft core body was adjusted by each feed roller pair. That is, as shown in FIG. 7, the shape of the groove provided on the outer peripheral surface of each feed roller is an R3.05 arc-shaped groove 36 slightly larger than the core metal. Then, the groove depth is adjusted, and the film thickness of the nylon layer (corresponding to 38 in FIG. 7) for the first roller, and the film thickness of the brass layer for the second roller (see FIG. 7) (corresponding to 38 in Fig. 7) was adjusted to the values shown in Table 1. The smaller the thickness, the lower the pressure applied by the pair of feed rollers to the shaft core.

  The thickness 38 of the above layer is the distance between the shafts of each pair of feed rollers, the linear distance of the exposed part of the shaft, and a non-contact laser measuring machine (trade name: LS-5120; manufactured by Keyence Corporation). ) Is a value obtained from the measured value measured by (1).

  In the calculation of equation (1), the elastic modulus of MC nylon was 3500 Mpa, and the elastic modulus of brass was 110000 Mpa.

  An air cylinder (trade name: CDQ2B63-20D; manufactured by SMC) was used as the pressurizing means 31, and the block 28b was pressed against the block 28a with air having a pressure of 0.5 Mpa.

Set the feed speed of the shaft member about 60 mm / sec, the rear end face of the preceding mandrel and brought into contact with the front end surface of the succeeding mandrel by transporting the mandrel to continuously crosshead It was. And the film of the raw material composition was formed in the surrounding surface of each axial core, and the unvulcanized roller was extruded from the die | dye.

  The extruded unvulcanized roller was heated at 160 ° C. for 60 minutes in a heating furnace using hot air to produce 100 elastic rollers.

  About each of 100 obtained elastic rollers, the outer diameter was measured using the laser outer diameter measuring device (LS-7030: Keyence Corporation make). For each roller, 47 points were measured at a pitch of 5 mm with respect to the elastic layer width of 232 mm, and the difference between the maximum value and the minimum value was obtained. The value of the roller having the largest difference among the 100 rollers is shown in Table 3 as the outer diameter accuracy.

[Example 2]
The depth of the groove on the outer peripheral surface of each feed roller was adjusted so that the thicknesses of the resin layer and metal layer were as shown in Table 1. Otherwise, an elastic roller was prepared and evaluated in the same manner as in Example 1. The results are shown in Table 3.

[Example 3]
The material of the layer around the core of the first roller is polyacetal resin (POM, elastic modulus 2800 MPa) (Derlin 100P; manufactured by DuPont), and the depth of the grooves on the outer peripheral surfaces of the first roller and the second roller is The thickness of each resin layer and metal layer was changed to the values shown in Table 1. Otherwise, an elastic roller was prepared and evaluated in the same manner as in Example 1. The results are shown in Table 3.

[Example 4]
Three pairs of feed rollers of the transport unit were used, and the pressure applied to the block was 0.34 MPa. Further, the depth of the groove on the outer peripheral surface of each feed roller was adjusted so that the thicknesses of the resin layer and the metal layer were as shown in Table 1. Otherwise, an elastic roller was prepared and evaluated in the same manner as in Example 1. The results are shown in Table 3.

[Examples 5 to 9]
The depth of the groove on the outer peripheral surface of each feed roller was adjusted so that the thicknesses of the resin layer and metal layer were as shown in Table 1. Otherwise, an elastic roller was prepared and evaluated in the same manner as in Example 1. The results are shown in Table 3.

[Comparative Examples 1-3]
The material of the layer around the core of the feed roller, the thickness of the resin layer, and the metal layer were changed to the thicknesses shown in Table 2. Otherwise, an elastic roller was prepared and evaluated in the same manner as in Example 1. The results are shown in Table 3.

  As a result, in the example, it was found that the maximum value of the fluctuation of the outer diameter of the elastic roller was small, and the shaft core body was stably conveyed.

  On the other hand, the elastic roller according to the comparative example had a large variation in outer diameter. Thereby, it turned out that the conveyance accuracy of a shaft core body is not enough. In particular, in Comparative Example 1, there was a case in which the shaft core did not enter between the feed rollers in the middle, resulting in a biting failure, and the outer diameter of the elastic roller varied greatly.

It is the schematic which shows an example of the manufacturing apparatus of the elastic roller of this invention. It is the schematic which shows the conveyance unit in the manufacturing apparatus of the elastic roller shown in FIG. It is the schematic which shows the feed roller in the conveyance unit shown in FIG. It is explanatory drawing which shows the groove | channel which may be provided in the outer peripheral surface of the feed roller in the conveyance unit shown in FIG. It is a block diagram which shows the crosshead in the manufacturing apparatus of the elastic roller shown in FIG. It is sectional drawing which shows the die | dye of the front-end | tip of the crosshead shown in FIG. It is explanatory drawing of the feed roller used for the Example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Extruder 11 Cross head 12 axis | shaft core 14 Conveyance unit 25-1, 25-2, 25-3, 25-4 Pair of feed roller

Claims (3)

An apparatus for manufacturing an elastic roller in which the periphery of the shaft core is covered with an elastic layer,
And crosshead has a feed roller pairs for sequentially conveyed to the crosshead of the mandrel,
Of the plurality of pairs of feed rollers, the pair of feed rollers arranged at the position farthest from the cross head is a pair of first rollers having a layer containing resin or rubber around the cored bar. Consists of
The at least one pair of feed rollers comprises a second pair of rollers having a metal layer around the core; and
An apparatus for manufacturing an elastic roller, characterized in that the pressing force of the shaft core body by the pair of second rollers is larger than the pressing force of the shaft core body by the pair of first rollers. The thickness of the layer containing the resin or rubber of the first roller when the shaft core is not conveyed is T1a, and the thickness of the metal layer of the second roller is T2a.
The thickness of the layer containing the resin or rubber of the first roller during conveyance of the shaft core body is T1b, the thickness of the metal layer of the second roller is T2b, and
When the elastic modulus of the layer containing the resin or rubber of the first roller is Ea and the elastic modulus of the metal layer of the second roller is Eb, the pair of the first rollers so as to satisfy the formula (1). The elastic roller manufacturing apparatus according to claim 1, wherein the pressure applied to the shaft core body by the pair of second rollers is adjusted.
[(T1a−T1b) / T1a] · Ea <[(T2a−T2b) / T2a] · Eb (1) A method for manufacturing an elastic roller in which the periphery of the shaft core is covered with an elastic layer using the elastic roller manufacturing apparatus according to claim 1,
A first step of conveying a plurality of shaft cores to the crosshead;
A second step of covering the periphery of the shaft core body with a layer made of the material of the elastic layer in the crosshead;
The first step includes a step of transporting the plurality of shaft core bodies toward the cross head so that the front end of the subsequent shaft core body is always in contact with the rear end of the preceding shaft core body. A method for producing an elastic roller.

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