JP2005103901A - Mold for manufacturing roller member - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a mold for manufacturing a roller member capable of properly controlling the cell roughness of an internal cell and capable of preventing the occurrence of a waste raw material to contribute to the enhancement of a yield. <P>SOLUTION: This mold for manufacturing the roller member is equipped with a hollow columnar mold main body and the cap members 2 inserted in both end opening parts of the mold main body to close the opening parts and constituted so as to inject a raw material in the mold main body in a state that a core is provided on the center line of the mold main body to manufacture the roller member. Each of the cap members 2 is formed into a tapered shape at least in an insertion part 11 and at least one groove 12 extending almost in the insertion direction to allow the inside of the mold main body to communicate with the outside at the time of closing is provided to the outer periphery of the insertion part formed into a tapered shape. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a roller member manufacturing mold (hereinafter, also simply referred to as “mold”), and more particularly, to a roller member manufacturing mold for manufacturing various roller members used in an image forming apparatus or the like.

  In electrophotographic apparatuses and electrostatic recording apparatuses such as copying machines, printers and facsimiles, developing rollers, toner supply rollers, and cleaning rollers are used in each process of development, toner layer formation, cleaning, paper feeding, and conveyance in the electrophotographic process. Various roller members such as a paper feed roller and a transport roller play various roles.

  These roller members have a structure in which an elastic layer made of a rubber material or a resin material is supported on the outer periphery of the shaft, and in particular, the elastic layer is formed of a foam made of a low hardness polymer elastic foam. Many roller members having a foam layer are used. In a roller member provided with such a foam layer, it is important that the foam layer has a uniform cell structure over the entire member, thereby achieving a uniform hardness according to the application.

  As a method of manufacturing such a roller member, a method of forming a foam layer by integral molding with a shaft using a mold in which a shaft is previously arranged is generally used. In order to obtain good roller performance, various methods are available. Manufacturing methods have been studied and proposed. An example of a mold that can be used in such a manufacturing method is shown in FIG.

  The illustrated mold 20 includes a hollow columnar mold main body 21 and caps 22 a and 22 b that are inserted into both ends thereof and hold the core metal 23, and the core metal 23 penetrates the center line of the mold main body 21. In this state, the raw material 24 is injected into the roller member to produce it. In the mold 20, first, as shown in (a) in the figure, a predetermined amount of the raw material 24 is injected into the inside from the hole 25 a of the upper cap 22 a. In this case, as the raw material 24 is filled up to the lower end inside the mold 20, air escapes from the hole 25 b of the lower cap 22 b. After the injection of the raw material 24, the holes 25a and 25b of the caps 22a and 22b are closed with lids 26a and 26b, respectively, as shown in FIG. Thereafter, foaming is started by the foaming action of the raw material 24, and the foamed raw material is filled into the mold 20.

  A perspective view of the cap 22 is shown in FIG. As shown in the figure, the cap 22 has a core metal receiving hole 27 for fitting a core metal provided at the center and an air vent hole provided in the middle not contacting the inner surface of the mold body 21. Part 25.

  In addition, as a technique for improving the roller performance by improving the mold itself, for example, in order to prevent the occurrence of pinholes due to the mixing of air into the product and to ensure a good shape of the details of the members There is a vacuum forming technique for forming a roller in a state in which the internal pressure is controlled by removing air from the mold. FIG. 4 shows a schematic cross-sectional view of a mold used for such vacuum forming.

  The illustrated mold 30 includes a hollow columnar mold main body 21 and caps 22 a and 22 b that are inserted into both ends thereof and hold the core metal 23, and the core metal 23 is provided through the center line of the mold main body 21. The roller member is manufactured by injecting the raw material 24 into the inside in the same manner as in the mold 20 shown in FIG. In this mold 30, after injecting the raw material 24, as shown in the figure, the holes 25 a and 25 b of the caps 22 a and 22 b are closed with vacuuming lids 28 a and 28 b, respectively, and vacuumed by a vacuum pump (not shown). Pull. Thereby, since the raw material 24 foamed inside leaks out from the inside of the mold main body 21 to the outside, the holes 25a and 25b are surely clogged by the leaked foam raw material (FIG. 3). Even in the case of the mold 20 shown in FIG. 4, the holes 25a and 25b may be partially clogged with foaming raw materials.

  As described above, in the manufacture of a roller member having a foam layer, it is required to realize a roller member having a uniform cell structure with a desired roughness over the entire member. However, the mold 20 generally used conventionally as shown in FIG. 3 cannot sufficiently satisfy this requirement.

  That is, in the mold 20 shown in the figure, the cell roughness fluctuates due to the fitting of the lids 26a and 26b. If the fitting is too tight, the cell becomes finer or air is not released, so foaming is not possible. The product will stop and a short circuit will occur. On the other hand, if the fit is too loose, the cell becomes rough, and in some cases, leakage of the raw material occurs. In addition, the material 24 inevitably leaks when the air is vented from the lower hole portion 25b, so that the injection amount varies and the material 24 is wasted. Further, when molding is performed with the mold 20 placed vertically as shown in the drawing, a difference in density occurs between the top and bottom of the product due to the difference in internal pressure, and the roller performance is impaired.

  Accordingly, the object of the present invention is to solve the above-described problems in the prior art and to appropriately control the cell roughness of the internal cells, and to contribute to the improvement of yield by preventing the generation of waste raw materials. An object of the present invention is to provide a die for producing a roller member.

  As a result of intensive studies, the present inventors have appropriately controlled the foaming pressure of the roller member at the time of molding by improving the cap member used for closing the die body in the die for roller member production. As a result, it was found that a desired cell roughness can be realized in the obtained roller member, and the present invention has been completed.

In order to solve the above problems, a roller member manufacturing mold of the present invention includes a hollow columnar mold main body, a cap member that is fitted into both end openings of the mold main body and closes the opening, In a mold for roller member production in which a raw material is injected into the mold body to produce a roller member in a state where a core bar is provided on the center line of the mold body,
The cap member is formed in a taper shape at least in the insertion portion, and extends substantially in the insertion direction on the outer periphery of the insertion portion formed in the taper shape. And having at least one groove that communicates with each other.

  In the metal mold | die of this invention, it is preferable that the semicircular, U-shaped or V-shaped induction groove is provided in the insertion direction inner end part of the said groove | channel. In addition, the groove is preferably provided with a most depressed portion of the outer peripheral surface of the inner end portion in the insertion direction of the cap member as a starting point. Further, the cap member is preferably made of polypropylene, and the groove is preferably provided with at least two.

  In the present invention, with the above configuration, the pressure in the mold at the time of foam molding of the roller member, that is, the foam pressure can be appropriately adjusted and obtained through the groove provided in the cap member. In the roller member, a desired cell roughness can be easily and reliably realized. Further, when the leakage of air and foaming pressure is completed, the raw material continues to enter the groove, and is in a sealed state in which the raw material is self-sealed. Therefore, there is no generation of waste materials due to the occurrence of further leakage, and production with a high yield becomes possible.

  The conventional vacuum forming technique described above is similar to the present invention in that the molding is performed by controlling the internal pressure, but the control of the cell roughness is performed in order to prevent pinholes and to ensure the shape. The technical idea is different from the intended present invention. In addition, there is a drawback that foamed polyurethane enters the mold cap for controlling the foaming pressure, and either the clogged foamed polyurethane is removed or it is disposable as a consumable part for reuse. Thus, there is a problem that an extra process and cost are required. In the present invention, unnecessary foaming material leaks out of the groove, and after demolding, the foaming material does not remain inside the cap member. Therefore, such a problem does not occur, and the cap member can be easily reused. Is possible.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
In FIG. 1, the structural example of the metal mold | die for roller member manufacture of this invention is shown. The illustrated mold 10 includes a hollow columnar mold main body 1 and a cap member 2 that is inserted into both end openings to close the opening, and the core metal 3 is placed on the center line of the mold main body 1. In a state where the roller member is provided, the raw material 4 is injected into the mold main body 1 to manufacture the roller member.

  FIG. 2 shows an enlarged perspective view of the cap member 2 according to the present invention. As shown in the figure, the cap member 2 is formed in a taper shape at least in the insertion portion 11 to be inserted into the opening of the mold body 1, and a groove extending in a substantially insertion direction on the outer periphery of the insertion portion 11. Two 12 are provided. In the present invention, when the mold is closed, the inside of the mold main body 1 communicates with the outside through the groove 12, and leakage of air and foaming pressure is performed.

  In the present invention, the foaming pressure at the time of foaming can be controlled by appropriately adjusting the cross-sectional dimensions and the number of the grooves 12 provided in the cap member 2, and thereby the roughness of the foamed cells can be controlled. . Specifically, by increasing the total cross-sectional area of the grooves 12 determined by the cross-sectional dimensions and the number of the grooves 12, the amount of leakage increases, that is, the pressure inside the mold decreases, and rough cells are formed. The On the other hand, by reducing the total cross-sectional area of the groove 12, the amount of leakage is reduced, that is, the pressure inside the mold is increased, and fine cells are formed. Usually, if the number of grooves having the same cross-sectional area is doubled, the leakage amount is also doubled. Therefore, as long as the number of the grooves 12 has a cross-sectional area corresponding to the desired cell roughness, it is possible to obtain the effect of the present invention by providing at least one, but it is possible to effectively remove the foaming pressure. From the viewpoint of achieving a good balance, it is preferable to provide at least two at equal intervals in the circumferential direction. In addition, about the cross-sectional dimension of the groove | channel 12, it is necessary to form in the shape of a narrow groove which can be sealed with the raw material 4 after the foaming pressure leaks.

  Moreover, as shown in the figure, it is preferable that a guide groove 13 is provided at the inner end of the groove 12 in the insertion direction. By providing the guide groove 13, the air flow can be improved and the end shape of the obtained roller member can be made uniform. The shape of the guide groove 13 may be U-shaped, semicircular, etc. in addition to the V-shape shown in the figure, and is not particularly limited. Moreover, when forming in V shape, the angle of the V shape is preferably about 90 degrees.

  Further, it is preferable that the groove 12 is provided with the most depressed portion of the outer peripheral surface of the inner end portion in the insertion direction of the cap member 2 as a starting point, so that air can be leaked more smoothly. In the illustrated example, the groove 12 is started from the most depressed portion A of the outer peripheral surface via the guide groove 13. In addition, although the length which provides the groove | channel 12 is decided by the length of the insertion part 11 and the presence or absence of the induction | guidance | derivation groove | channel 13, if the length of the groove | channel 12 is too short, for example, less than about 5 mm, the amount of leak will increase and it will be stabilized. As a result, the amount of leakage cannot be properly controlled, which is not preferable.

  In the mold 10 of the present invention, it is important that the cap member 2 used for closing the opening at both ends is provided with the groove 12 as described above so that the leak amount of air and foaming pressure can be adjusted. There is no particular limitation on the structure, shape, etc., and it can be determined appropriately according to conventional methods.

  For example, the mold body 1 may have any shape as long as the opening portions at both ends are formed in a shape into which the cap member 2 can be inserted, and the material thereof is a metal such as iron, copper, aluminum, or stainless steel. In addition, ceramics or the like can be used. Preferably, stainless steel is used in terms of strength, rust prevention, cost, and the like. Also, the material of the cap member 2 is not particularly limited as long as it can withstand the heating during molding, but from the viewpoint of releasability of the roller member after molding, it is preferable to use polypropylene. .

  Hereinafter, a method for manufacturing a roller member using the mold 10 of the present invention will be described with reference to FIG. First, as shown to (a) in a figure, in the state which penetrated the metal core 3 on the centerline of the metal mold | die body 1, the metal mold | die 10 is arrange | positioned so that a longitudinal direction may become substantially horizontal, and inside Raw material 4 is injected. Next, the cap member 2 is inserted into both ends, and the mold 10 is pressurized from both ends. Next, the raw material inside starts to foam, and the foamed raw material is filled into the mold 10 as shown in FIG.

  In the present invention, since the internal pressure of the mold is controlled through the leakage of foaming pressure by the action of the cap member 2 at this time, it is possible to achieve appropriate hardness as desired in the obtained roller member. Become. Further, as shown in the drawing, by using a method in which the mold 10 is placed horizontally and the raw material 4 is injected in the vicinity of the central portion in the longitudinal direction, foaming of the raw material can be progressed uniformly toward both ends. The cell structure can be made more uniform, and a roller member having no hardness difference in the longitudinal direction can be obtained. Therefore, when the mold 10 of the present invention is used in combination with this manufacturing method, it is more effective for manufacturing a high-quality roller member.

  The material of the shaft of the roller member that can be applied to the mold 10 of the present invention and the blending of the raw materials are not particularly limited, and commonly used materials can be appropriately used. By using a shaft and using a polyurethane material as a material, a polyurethane roller member having a structure in which a polyurethane foam layer is supported on the outer periphery of the shaft can be obtained. As such a polyurethane raw material, for example, the following polyisocyanate component and polyol component can be used.

  As the polyisocyanate component, aromatic isocyanate, aliphatic isocyanate, alicyclic isocyanate, and derivatives thereof can be used. Among them, aromatic isocyanate and derivatives thereof, particularly tolylene diisocyanate, diphenylmethane diisocyanate, and these Derivatives are preferably used.

  Examples of tolylene diisocyanate and derivatives thereof include crude tolylene diisocyanate, 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, and a mixture of 2,4-tolylene diisocyanate and 2,6-tolylene diisocyanate. These urea-modified products, burette-modified products, carbodiimide-modified products, and the like are used.

  Moreover, as diphenylmethane diisocyanate and derivatives thereof, for example, diphenylmethane diisocyanate and derivatives thereof obtained by phosgenating diaminodiphenylmethane and derivatives thereof are used. Examples of the derivatives of diaminodiphenylmethane include polynuclear bodies, and pure diphenylmethane diisocyanate obtained from diaminodiphenylmethane, polymeric diphenylmethane diisocyanate obtained from a polynuclear body of diaminodiphenylmethane, and the like can be used. Regarding the number of functional groups of polymeric diphenylmethane diisocyanate, a mixture of pure diphenylmethane diisocyanate and polymeric diphenylmethane diisocyanate having various functional groups is usually used, and the average number of functional groups is preferably 2.05 to 4.00, more preferably 2. .50 to 3.50 are used. Derivatives obtained by modifying these diphenylmethane diisocyanates and derivatives thereof, such as urethane-modified products modified with polyols, dimers formed by uretidione formation, isocyanurate-modified products, carbodiimide / uretonimine-modified products, allophanate-modified products , Urea-modified products, burette-modified products, and the like can also be used. Further, several types of diphenylmethane diisocyanate and derivatives thereof may be blended.

  As the polyol component, polyether polyol obtained by addition polymerization of ethylene oxide and propylene oxide, polytetramethylene ether glycol, polyester polyol obtained by condensing acid component and glycol component, polyester polyol obtained by ring-opening polymerization of caprolactone, polycarbonate diol, etc. are used. be able to.

  Examples of polyether polyols obtained by addition polymerization of ethylene oxide and propylene oxide include water, propylene glycol, ethylene glycol, glycerin, trimethylolpropane, hexanetriol, triethanolamine, diglycerin, pentaerythritol, ethylenediamine, and methylglucotite. , Aromatic diamine, sorbitol, sucrose, phosphoric acid, etc. as starting materials, and those obtained by addition polymerization of ethylene oxide and propylene oxide. Particularly, water, propylene glycol, ethylene glycol, glycerin, trimethylolpropane. Those starting from hexanetriol are preferred. Regarding the ratio of ethylene oxide and propylene oxide to be added and the microstructure, the ratio of ethylene oxide is preferably 2 to 95% by weight, more preferably 5 to 90% by weight, and ethylene oxide is added to the terminal. preferable. In addition, the arrangement of ethylene oxide and propylene oxide in the molecular chain is preferably random.

  The molecular weight of the polyether polyol is bifunctional when water, propylene glycol, or ethylene glycol is used as a starting material, and preferably has a weight average molecular weight in the range of 300 to 6000, preferably in the range of 400 to 3000. Is more preferable. Further, when glycerin, trimethylolpropane, and hexanetriol are used as starting materials, they are trifunctional, and those having a weight average molecular weight in the range of 900 to 9000 are preferable, and those in the range of 1500 to 6000 are more preferable. Furthermore, a bifunctional polyol and a trifunctional polyol can be appropriately blended and used.

  Polytetramethylene ether glycol can be obtained, for example, by cationic polymerization of tetrahydrofuran, and those having a weight average molecular weight in the range of 400 to 4000, particularly in the range of 650 to 3000 are preferably used. It is also preferable to blend polytetramethylene ether glycols having different molecular weights. Furthermore, polytetramethylene ether glycol obtained by copolymerizing an alkylene oxide such as ethylene oxide or propylene oxide can also be used.

  Further, it is also preferable to use a blend of polytetramethylene ether glycol and a polyether polyol obtained by addition polymerization of ethylene oxide and propylene oxide. In this case, it is preferable to use such a blend ratio so that the weight ratio is in the range of 95: 5 to 20:80, particularly 90:10 to 50:50.

  In addition to the polyol component, a polymer polyol obtained by modifying the polyol with acrylonitrile, a polyol obtained by adding melamine to the polyol, a diol such as butanediol, a polyol such as trimethylolpropane, or a derivative thereof may be used in combination.

  These polyol component and polyisocyanate component may be used by prepolymerizing polyol with polyisocyanate in advance. As the method, a polyol and a polyisocyanate are put in a suitable container, sufficiently stirred, and kept at 30 to 90 ° C., preferably 40 to 70 ° C. for 6 to 240 hours, preferably 24 to 72 hours. Is mentioned.

  Catalysts used for the curing reaction of polyurethane raw materials include monoamines such as triethylamine and dimethylcyclohexylamine, diamines such as tetramethylethylenediamine, tetramethylpropanediamine, and tetramethylhexanediamine, pentamethyldiethylenetriamine, pentamethyldipropylenetriamine, tetra Triamines such as methylguanidine, triethylenediamine, dimethylpiperazine, methylethylpiperazine, cyclic amines such as methylmorpholine, dimethylaminoethylmorpholine, dimethylimidazole, dimethylaminoethanol, dimethylaminoethoxyethanol, trimethylaminoethylethanolamine, methylhydroxy Alcohol amines such as ethyl piperazine and hydroxyethyl morpholine; (Dimethylaminoethyl) ether, ether amines such as ethylene glycol (dimethyl) aminopropyl ether, stannous octoate, dibutyltin diacetate, dibutyltin dilaurate, dibutyltin marker peptide, dibutyltin thiocarboxylate, dibutyltin dimaleate, dioctyl And organometallic compounds such as tin marker peptide, dioctyl tin thiocarboxylate, phenylmercury propionate and lead octenoate. These catalysts may be used alone or in combination of two or more.

  When imparting conductivity to the roller member, a conductive material can be added to a raw material such as a polyurethane raw material. Conductive materials include ionic conductive materials and electronic conductive materials, and ionic conductive materials include octadecyltrimethylammonium such as dodecyltrimethylammonium such as tetraethylammonium, tetrabutylammonium and lauryltrimethylammonium, hexadecyltrimethylammonium and stearyltrimethylammonium. , Ammonium perchlorate such as benzyltrimethylammonium and modified aliphatic dimethylethylammonium, chlorate, hydrochloride, bromate, iodate, borofluoride, sulfate, alkylsulfate, carboxylic acid Organic ionic conductive materials such as salts and sulfonates; perchlorates, chlorates, hydrochlorides, bromates, iodates, and borates of alkali metals or alkaline earth metals such as lithium, sodium, calcium, and magnesium Hydroiodide, trifluoromethyl sulfate, and inorganic ion conductive material such as sulfonate. Further, as the electronic conductive material, conductive carbon black such as ketjen black, acetylene black, etc .; carbon black for rubber such as SAF, ISAF, HAF, FEF, GPF, SRF, FT, MT; for ink such as oxidized carbon black Carbon black, pyrolytic carbon black, graphite; conductive metal oxides such as tin oxide, titanium oxide, and zinc oxide; metals such as nickel and copper; carbon whiskers, graphite whiskers, titanium carbide whiskers, conductive potassium titanate whiskers, Examples thereof include conductive whiskers such as conductive barium titanate whiskers, conductive titanium oxide whiskers, and conductive zinc oxide whiskers. By appropriately adding these conductive materials, the volume specific resistance of the roller member can be adjusted.

  In addition, in raw materials such as polyurethane raw materials, in addition to the above conductive materials, fillers such as inorganic carbonates, foam stabilizers such as silicone foam stabilizers and various surfactants, phenol, phenylamine, etc. An antioxidant, a low friction agent, a charge adjusting agent, and the like can be appropriately added. Among these, as the silicone foam stabilizer, a dimethylpolysiloxane / polyoxyalkylene copolymer or the like can be suitably used, and comprises a dimethylpolysiloxane moiety having a molecular weight of 350 to 15000 and a polyoxyalkylene moiety having a molecular weight of 200 to 4000. Those are particularly preferred. The molecular structure of the polyoxyalkylene moiety is preferably an addition polymer of ethylene oxide or a co-addition polymer of ethylene oxide and propylene oxide, and its molecular terminal is preferably ethylene oxide. Examples of the surfactant include cationic surfactants, anionic surfactants, ionic surfactants such as amphoteric, and nonionic surfactants such as various polyethers and various polyesters. The blending amount of the silicone foam stabilizer and various surfactants is preferably 0.1 to 10 parts by weight, more preferably 0.5 to 5 parts by weight with respect to 100 parts by weight of the polyurethane raw material.

Hereinafter, the present invention will be described specifically by way of examples.
Comparative Example A core metal 23 (made by SUM) having an outer diameter of 6 mm is set in advance on a mold 20 (inner diameter φ16.0 mm, outer diameter φ20.0 m, made by SUS) having the shape shown in FIG. Preheating was performed to 80 ° C. Thereafter, the polyurethane raw material is injected into the inside while removing air from the hole 25b of the lower cap 22b, the upper and lower holes 25a and 25b are respectively closed by the lids 26a and 26b, and the polyurethane raw material is foamed by the action of internal pressure. Thus, the foaming raw material was filled into the mold 20. This was cured at 110 ° C. for 10 minutes and demolded to obtain a roller member of a comparative example.

Example 1
A core metal 3 (made by SUM) having an outer diameter of 6 mm is set in advance in the mold 10 (inner diameter φ16.0 mm, outer diameter φ20.0 m, made by SUS) shown in FIG. Pre-heating was performed. Thereafter, as shown in the figure, a polyurethane raw material similar to that of the comparative example is injected in the vicinity of the central portion in the longitudinal direction inside the mold body 1, and the cap member 2 is inserted into both ends to close the mold 10, and from both ends. Pressurized. The raw material inside was filled by foaming inside the mold 10. At this time, leakage of air and foaming pressure was performed by the groove 12 provided in the cap member 2. The cap member 2 used was provided with two grooves 12 as shown in Table 1 below at intervals of 180 °. This was cured at 110 ° C. for 10 minutes and demolded to obtain a roller member of Example 1.

Example 2
A roller member of Example 2 was produced in the same manner as in Example 1 except that a cap member 2 having four grooves as shown in Table 1 below at 90 ° intervals was used. .

  For each roller member sample of Comparative Example and Examples 1 and 2, three points were taken in the longitudinal direction, and the Asker FP hardness at each point was measured and the cell roughness was evaluated. In all samples, the hardness and cell roughness were uniform between the points, whereas the sample of the comparative example had higher hardness from the upper side to the lower side during vertical installation, and the cell roughness was dense. And had a non-uniform structure in the longitudinal direction.

Examples 3-5
Next, the leak amount and cell roughness (cell size) were measured using the cap members 2 provided with grooves under the conditions shown in Table 1 below. The obtained results are also shown in Table 1 below. As can be seen from the results in Table 1 below, the amount of leakage can be adjusted by appropriately setting the total cross-sectional area of the groove and the length of the groove determined from the cross-sectional area and the number of grooves. It became possible to control the height.

＊１：溝形状は、夫々図５中に示す断面形状を有することを意味する。
＊２：金型本体１とキャップ部材２を加圧して、１ｋＰａの圧力のエアーを注入した際のリーク量を測定した値である（図６参照）。

* 1: Groove shape means having the cross-sectional shape shown in FIG.
* 2: A value obtained by measuring the amount of leakage when pressurizing the mold body 1 and the cap member 2 and injecting air at a pressure of 1 kPa (see FIG. 6).

  As described above, according to the present invention, the roller capable of appropriately controlling the cell roughness of the internal cell and contributing to the improvement of the yield by preventing the generation of the waste material. It is possible to realize a member manufacturing mold.

(A) And (b) is sectional drawing which shows the metal mold | die for roller member manufacture of this invention. It is an expansion perspective view which shows the cap member which concerns on this invention. (A) And (b) is sectional drawing which shows the conventional type | mold, (c) is an expansion perspective view of a cap. It is sectional drawing which shows an example of the type | mold used for the conventional vacuum forming. (A) And (b) is an example of the cross section of a cap member. It is explanatory drawing of the measuring method of the leak amount which concerns on an Example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1,21 Mold body 2 Cap member 3,23 Core metal 4,24 Raw material 10 Roller member manufacturing die 11 Insertion portion 12 Groove 13 Guide groove 20 Mold 22a, 22b Cap 25a, 25b Hole portion 26a, 26b Lid 27 Hole for receiving cored bar 28a, 28b Lid for vacuuming

Claims (5)

A hollow columnar mold body, and a cap member that is fitted into both opening portions of the mold body to close the opening portion, and the core metal is inserted through the center line of the mold body. , In a roller member manufacturing mold for manufacturing a roller member by injecting raw material into the mold body,
The cap member is formed in a taper shape at least in the insertion portion, and extends substantially in the insertion direction on the outer periphery of the insertion portion formed in the taper shape. A roller member manufacturing die having at least one groove communicating with each other.   The roller member manufacturing die according to claim 1, wherein a semicircular, U-shaped or V-shaped guide groove is provided at an inner end of the groove in the insertion direction.   3. The roller member manufacturing die according to claim 1, wherein the groove is provided starting from the most depressed portion of the outer peripheral surface of the inner end portion in the insertion direction of the cap member.   The roller member manufacturing die according to any one of claims 1 to 3, wherein the cap member is made of polypropylene. The roller member manufacturing die according to any one of claims 1 to 4, which has at least two grooves.

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