JP2019051730A - Method of manufacturing roller member, roller member mold, roller shaft, and roller member - Google Patents

Abstract

To integrally mold a friction material to a roller shaft without resin leakage and with excellent shape, positional accuracy, and bonding strength of a roller part, and to manufacture roller components excellent in transfer performance at a very low cost.SOLUTION: A roller shaft 1 is inserted into a mold comprising a mold member 7 having a first mold surface defining an outer peripheral part of a roller part 2 and mold members 8, 9 respectively having second and third mold surfaces defining first and second flat surface parts 3, 3 of the roller part 2, and then the mold is closed. Subsequently, a molding material is injected around the roller shaft 1 to integrally mold the roller part 2. The roller part 2 includes the outer peripheral part, and the first and second flat surface parts 3, 3 rising from the roller shaft 1 to the outer peripheral part. The roller shaft 1 includes flange parts 4, 4 at parts corresponding to the first and second flat surface parts 3, 3, which prevent the molding material from leaking outward from the first and second flat surface parts 3, 3 when the roller part 2 is integrally molded around the roller shaft 1 by casting.SELECTED DRAWING: Figure 6

Description

  The present invention relates to a method for manufacturing a roller member in which a molding material is injected around a roller shaft and a roller portion is integrally formed with the roller shaft, and a roller member mold used for molding the roller member.

  Conventionally, a roller member is used in a conveyance system that handles sheet materials (paper, plastic sheets, etc.) such as a copying machine and a printer. This type of roller member may be manufactured by a process of press-fitting a roller portion molded with a synthetic rubber material into a roller shaft, for example. Such a method has a problem that man-hours are large and manufacturing costs increase.

  In addition, when the roller part is press-fitted into the roller shaft, two flange portions are provided near both ends of the roller portion as a guide for positioning the rubber roller portion in the axial direction on the roller shaft. Fine adjustment may be made so that the rubber roller portion is positioned inside the portion. However, in such a manufacturing method, a gap may be formed between the two flange portions and the rubber roller portion during the press-fitting process, so that the accuracy of the axial mounting position is deteriorated or the rubber roller portion is distorted. There was a problem that the external accuracy deteriorated. As a result, in order to improve the coaxial accuracy between the roller shaft and the rubber portion after press-fitting, further polishing of the outer periphery is required, which may cause further cost increase. Furthermore, since the positioning is performed only by press-fitting, there is a possibility that the roller portion is displaced due to insufficient bonding strength with the roller shaft.

  In view of the above problems, conventionally, a method has been proposed in which the friction material of the sheet conveying roller member and the roller body are integrally formed by two-color molding in a copying machine or the like in which the friction material is provided on the outer periphery of the roller body. (For example, Patent Document 1 below). In Patent Document 1, the friction material is formed so as to be integrally interposed between a plurality of branch portions provided on the outer periphery of the roller body and provided at substantially equal intervals. According to the structure of Patent Document 1, the friction material and the roller main body are formed by molding in two colors (twice), and the work of assembling the friction material and the roller main body later becomes unnecessary.

JP-A-9-202486

  In the prior art as disclosed in Patent Document 1, a roller body (roller shaft) and a friction material (roller portion) are integrally formed on the outer periphery thereof by two-color molding. In this document, the configuration of the molding die is not particularly shown, but it is necessary to form cavities (voids) without gaps when molding, for example, a thermoplastic elastomer resin as a friction material on the outer periphery of the roller body. However, in general, a roller body molded first (first color) from the resin has a lower shape accuracy than the mold, and it is extremely difficult to bring all the contact portions with the mold into contact with no gap. As a result, there is a problem in that a gap is generated at a portion corresponding to the boundary between the roller body (roller shaft) and the friction material, and the resin flows into the portion to cause resin leakage. If this resin leakage occurs, the friction material (roller portion) may become defective due to the occurrence of sink marks, or even a slight resin leakage may remain as burrs. There was a problem of increased costs.

  The problem of the present invention is that the outer shape and positional accuracy of the roller portion and the bonding strength are good, the friction material can be integrally formed with the roller shaft without resin leakage, and the roller parts with excellent conveying performance can be manufactured very simply and inexpensively. There is in doing so.

  In order to solve the above problems, in the present invention, a first mold surface that defines the outer peripheral portion of the roller portion and a second flat surface that rises to the outer peripheral portion of the roller portion are defined. A roller shaft is inserted into a mold having a mold surface and a third mold surface that defines a second plane portion that rises to the outer peripheral portion of the roller portion, the mold is closed, and the roller shaft In a method of manufacturing a roller member in which a molding material is injected around the roller and the roller portion is integrally formed with the roller shaft, first and second flange portions are respectively provided at portions corresponding to the first and second plane portions. An insert step of inserting and closing the roller shaft provided with the mold into the mold so that the second and third mold surfaces are in contact with and closely contact the first and second flange portions, respectively, and the mold Said first, second and third mold faces of the mold, Employing a structure including an injection step of injecting a molding material for forming the roller portion in the clearance defined between the fine said roller shaft.

  Alternatively, a first mold surface that defines the outer peripheral portion of the roller portion, a second mold surface that defines a first flat surface that rises to the outer peripheral portion of the roller portion, and the roller portion A third die surface defining a second flat surface rising to the outer peripheral portion, a roller shaft is inserted into a die, the die is closed, and a molding material is injected around the roller shaft to In the roller member formed integrally with the roller shaft, the roller portion includes an outer peripheral portion, a first flat portion that rises from the roller shaft to the outer peripheral portion, and a second that rises from the roller shaft to the outer peripheral portion. And a flange that prevents the molding material from leaking outside the first and second planar portions when the roller portion is integrally molded around the roller shaft by casting. At a position corresponding to the first and second plane portions. It adopted a configuration with, respectively.

  With the above configuration, according to the present invention, each mold and the roller shaft can be defined with the second and third mold surfaces in contact with and in close contact with the first and second flange portions of the roller shaft. A molding material for forming the roller portion is injected into the gap formed. For this reason, the outer shape and positional accuracy and bonding strength of the roller part are good, the friction material can be integrally formed with the roller shaft without resin leakage, and the roller parts with excellent conveyance performance can be manufactured very easily and inexpensively. There is an effect.

It is sectional drawing which showed the structure of the roller member shape | molded by the method of this invention. It is the perspective view which showed the structure of the roller member shape | molded by the method of this invention. It is the perspective view which showed the structure of the roller axis | shaft used when forming a roller member by the method of this invention. It is sectional drawing shown in the state which inserted the roller axis | shaft in the roller member metal mold | die used when shape | molding a roller member by the method of this invention, and this metal mold | die. It is sectional drawing which showed the roller member metal mold | die used when a roller member is shape | molded by the method of this invention in the mold closed state. It is sectional drawing shown in the state which inject | poured the molding material for integral molding into the roller member metal mold | die used when shape | molding a roller member by the method of this invention. It is sectional drawing which showed the schematic structure of the roller member metal mold | die used when shape | molding a roller member by the method of this invention, and a shaping | molding apparatus in a mold closed state. It is sectional drawing which showed the schematic structure of the roller member metal mold | die used when shape | molding a roller member by the method of this invention, and a shaping | molding apparatus in the mold open state. It is sectional drawing which showed the structure of the different roller member shape | molded by the method of this invention. It is sectional drawing shown in the state which inserted the roller axis | shaft in the roller member metal mold | die of FIG. It is sectional drawing which showed the roller member metal mold | die of FIG. 9 in the mold closed state. FIG. 10 is a cross-sectional view showing a state where a molding material for integral molding is injected into the roller member mold of FIG. 9. It is sectional drawing which showed the structure of the still different roller member shape | molded by the method of this invention. It is sectional drawing shown in the state which inserted the roller axis | shaft in the roller member metal mold | die of FIG. It is sectional drawing which showed the roller member metal mold | die of FIG. 13 in the mold closed state. It is sectional drawing shown in the state which inject | poured the molding material for integral molding into the roller member metal mold | die of FIG. It is the perspective view which showed the structural example of the roller member used for conveyance of a sheet material.

  DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments for carrying out the present invention will be described with reference to embodiments relating to an image forming apparatus shown in the accompanying drawings. The following embodiment is merely an example, and for example, a detailed configuration can be appropriately changed by those skilled in the art without departing from the gist of the present invention. Moreover, the numerical value taken up by this embodiment is a reference numerical value, Comprising: This invention is not limited.

  In this embodiment, as shown in FIG. 17, a roller member in which a roller portion 2 is integrally formed on a roller shaft 1 is taken as an example, and a roller member mold, a roller shaft, or an integral molding method for manufacturing the roller member is used. I will explain it. In FIG. 17, the roller portion 2 is integrally formed at two locations on the roller shaft 1. Such a roller member can be used as a roller member for conveying a sheet material (paper, plastic sheet, etc.) of a copying machine or a printer.

  FIG. 1 shows a cross-sectional structure of a roller member 12 formed by integrally forming a roller portion 2 on a roller shaft 1 in this embodiment. FIG. 2 is a perspective view showing the entire roller member 12 of FIG. FIG. 3 is a perspective view showing the structure of the roller shaft 1 used for integral molding of the roller member 12 of the present invention. In FIG. 1, the alternate long and short dash line indicates the (rotation) center of the roller shaft 1 (the same applies to other cross-sectional views described later).

  1 to 3, reference numeral 1 denotes a roller shaft, and 2 denotes a roller portion, each of which is made of a molding material as described later. The roller portion 2 is integrally formed of a molding material capable of forming a friction material on the outer periphery of the roller shaft 1 by a method as described later. The outer peripheral portion of the roller portion 2 constitutes a friction surface for conveying a sheet material and the like, and both end portions of the roller portion 2 are flat portions 3 and 3 that rise to the outer peripheral portion of the roller portion 2 (the first portion Plane part and second plane part).

  In the roller shaft 1 of the present embodiment, flange portions 4 and 4 (first and second flange portions) are provided at portions corresponding to the flat portions 3 and 3 of the roller portion 2, respectively. When the roller shaft 1 is formed, the flange portions 4 and 4 are formed integrally with the roller shaft 1 with a diameter larger than the outer shape of the roller shaft 1 and with a predetermined thickness over the entire circumference of the roller shaft 1. The flange portions 4, 4 form biting portions 5, 5 that bite toward the roller portion 2 as shown in FIG. 1 in the roller member 12 after integral molding.

  The roller shaft 1 is formed with a thinned portion 6 in order to reduce the thickness of the roller shaft 1 particularly in the lower portion (base or pedestal portion) of the roller portion 2 (FIGS. 1 and 3). The lightening portion 6 can be formed when the roller shaft 1 is formed. Further, the lightening portion 6 can be formed on a portion of the roller shaft 1 excluding the roller portion 2 (FIG. 2, FIG. 3 or FIG. 17). The portion left by forming the lightening portion 6 has a rib structure as shown in the figure, for example. The lightening portion 6 below the roller portion 2 is continuously filled with the same molding material as the roller portion 2. Thereby, the roller part 2 and the roller shaft 1 are firmly coupled, and the problem that the roller part 2 slides on the roller shaft 1 can be avoided.

  Further, as shown in FIG. 1, in this embodiment, the flange portions 4 and 4 of the roller shaft 1 bite into the roller portion 2 (5, 5) and are integrally formed, so there is no gap, and axial positional accuracy is obtained. Has the effect of being good. In addition, since it is integrally formed with no gap and the dimension in the radial direction is determined by the mold, the accuracy is good, and it is not necessary to perform polishing or the like in post-processing.

  Further, when the roller member 12 configured as shown in FIGS. 1 and 2 is used as a roller member for conveying a general sheet material or the like, a pressure contact force that compresses the entire roller portion 2 in the diameter direction thereof. Work. Such a pressure contact force is generated, for example, by an urging means using, for example, a spring or the like disposed inside a copying machine or a printer. On the other hand, in the roller member 12 of the present embodiment, as shown in FIG. 1, the biting portions 5 and 5 of the flange portions 4 and 4 have a thickness of the roller portion 2 in the diametrical direction as compared with other portions of the roller portion. One feature is that the thickness is reduced by the radial height of the flange portions 4 and 4. With such a structure, the repulsive force against the pressure contact force is greater in the roller portion 2 above the flange portions 4 and 4 (the biting portions 5 and 5) than in the other portions. For this reason, in the roller member 12 of the present embodiment, there is an effect that the grip force necessary for the conveyance is increased and the conveyance performance can be improved as compared with the conventional structure in which the flange portions 4 and 4 are not provided.

  Next, a roller member mold for manufacturing the roller member 12 shown in FIGS. 1 and 2, a method for manufacturing the roller member, and the like will be described with reference to FIGS. 4 to 8. FIG. 4 shows a configuration example of the roller molding die of the present embodiment in the form of a sectional view. The state of FIG. 4 is a state in which the mold is opened and the roller shaft 1 is inserted (inserted or placed) into the mold. In addition, the roller shaft 1 uses another mold separately in the shape having the flange portions 4 and 4 in the portion corresponding to the base of the hollow portion 6 and the roller portion (2) as shown in FIG. And injection molded.

  In FIG. 4, reference numeral 7 denotes a first mold member provided with a first mold surface that defines the outer peripheral portion of the roller portion 2. In addition, 8 is a second mold member having a second mold surface that defines one plane portion (3: first plane portion) of the roller portion 2, and 9 is the other mold portion of the roller portion 2. It is a 3rd metal mold | die member provided with the 3rd metal mold | die surface which defines a plane part (3: 2nd plane part).

  In this embodiment, the molding material injection port 10 is provided in the second mold member 8. In the state where the mold is not closed as shown in FIG. 4, there is a gap in each boundary portion 11 between the flange portion 4 and the second mold member 8 and the third mold member 9.

  Of the first to third mold members 7 to 9, an arbitrary mold member can be divided into a plurality of parts as necessary for convenience such as mold opening and taking out the roller member 12 (for example, a mold). Etc.). In FIG. 7 and FIG. 8 described later, an example of a divided structure of the mold members 7 to 9 is shown.

  However, the structure of the mold division such as the first mold member 7, the second mold member 8, and the third mold member 9 described above is merely an example, and the roller portion 2 can be injection-molded. A person skilled in the art may arbitrarily change the structure of the mold division. Whatever mold division structure is used, the essential mold surfaces in the present embodiment are at least the following three (the parentheses at the end of each bullet are the first to the first of the present embodiment). 3 shows the relationship with the mold member 3).

(1) First mold surface (first mold member 7) that defines the outer peripheral portion of the roller unit 2
(2) Second mold surface (second mold member 8) that defines a first flat surface portion (3) rising to the outer peripheral portion of the roller portion 2
(3) Third mold surface (third mold member 9) that defines a second flat surface portion (3) that rises to the outer peripheral portion of the roller portion 2
In the integral molding of the roller portion 2 of the present embodiment, the roller shaft 1 is inserted into the mold that defines the first to third mold surfaces, the mold is closed, and a molding material is placed around the roller shaft 1. This corresponds to a manufacturing method in which the roller portion 2 is integrally formed with the roller shaft 1 by pouring (casting).

  FIG. 5 shows a state before the mold of FIG. 4 is closed and the molding material is injected in the form of a sectional view. The state in FIG. 5 corresponds to a state in which the insertion process of the roller shaft 1 has been completed.

  As described above, the roller shaft 1 inserted in the mold includes the first and second flange portions 4 and 4 at portions corresponding to the first and second plane portions 3 and 3, respectively. . The cavity shape (or the shape of the roller shaft 1) defined by the first mold member 7, the second mold member 8, and the third mold member 9 is inserted into the roller shaft 1 and closed. At this time, the roller shaft 1 and the mold surface are configured to form the following contact state.

  That is, this contact state means that the first and second flange portions 4 and 4 of the roller shaft 1 have a second mold surface (second mold member 8) and a third mold surface (third The roller shaft 1 is inserted into the mold so that the mold members 9) come into contact with each other and come into close contact with each other.

  Alternatively, it is more preferable to form the following contact state. That is, the second mold surface (second mold member 8) and the third mold surface (third mold member 9) are in contact with the first and second flange portions 4 and 4 only. Rather, a contact state is formed in which the left and right flange portions 4 and 4 are pushed to the extent that they are elastically (or plastically) deformed inward.

  The above-mentioned contact state when the mold is inserted and closed is formed by the cavity shape defined by the mold, particularly the second mold member 8 and the third mold member 9. This can be realized by setting the dimensions of the roller shaft 1, particularly the first and second flange portions 4, 4.

  By forming the contact state as described above when the mold is inserted and closed, a second mold surface (second mold member 8) is formed on the first and second flange portions 4 and 4. In addition, the third mold surface (third mold member 9) can be brought into close contact with each other. Thereby, the clearance gap in the site | part of the boundary part 11 of the roller part 2 and the roller shaft 1 can be eliminated completely.

  The boundary portion 11 between the roller portion 2 and the roller shaft 1 corresponding to the base portion of the flat surface portions 3 and 3 of the roller portion 2 can be a path through which the molding material leaks to a portion other than the roller portion 2 of the roller shaft 1, for example. . However, in this embodiment, the roller shaft 1 is provided with the first and second flange portions 4 and 4, and the second mold surface (second mold member 8) and the third mold surface ( The third mold member 9) is configured to be in close contact. For this reason, it can prevent effectively that a molding material leaks to parts other than the roller part 2 of the roller shaft 1 of a molding material at the time of injection | pouring of the molding material mentioned later.

  FIG. 6 shows, in a cross-sectional view, a state in which the molding material for forming the roller portion 2 is injected from the injection port 10 after the insert and mold closing in FIG. 5 are completed. In FIG. 6, the molding material forming the roller portion 2 is illustrated by hatching. The molding material injected through the injection port 10 is injected into a cavity (gap) defined by the first to third mold members 7 to 9 as shown in FIG. Thus, the roller portion 2 and the lightening portion 6 of the roller shaft are filled.

  In the present embodiment, the second mold surface (second mold member) is formed on the first and second flange portions 4 and 4 by the mold cavity shape and the dimension setting of each part of the roller shaft 1 as described above. 8) and the third mold surface (third mold member 9) are in contact with each other and are in close contact with each other. Or, further, the second and third mold surfaces (second and third mold members 8 and 9) are elastically (or plastically) deformed inwardly on the left and right flange portions 4 and 4, respectively. A contact state that pushes in is formed. As a result, the gap at the boundary portion 11 between the roller portion 2 and the roller shaft 1 is completely shielded. Therefore, the filled molding material does not leak from the boundary portion 11 or remain as burrs, and a high-quality roller member 12 can be obtained only by integral (injection) molding without requiring post-processing or the like.

  7 and 8 show, in a cross-sectional view, a configuration example of a molding apparatus 100 for integrally (injecting) molding the roller portion 2 with respect to the roller shaft 1 using the roller member mold shown in FIGS. ing.

  7 and 8, the second mold member is substantially L-shaped so that the shape of the injection port 10 can be injected with the molding material from the upper bush 10a. The dimensions of the members are somewhat different from the states of FIGS.

  In the configuration of FIGS. 7 and 8, the first mold member 7 and the third mold member 9 are formed in a ring shape, as clearly shown in FIG. 101 is slidable left and right. For example, by forming the first mold member 7 and the third mold member 9 in an annular shape, the outer peripheral surface of the roller portion 2 can be integrally formed without generating a seam or the like. Further, the second mold member 8 in FIG. 7 is divided into, for example, an upper part and a lower part, and the upper half including the injection port 10 can be removed when the mold is opened as shown in FIG.

  However, the molds of FIGS. 7 and 8 and the first to third mold members 7 to 9 still function as in FIGS. 4 to 6 with respect to the manufacturing process of integrally forming the roller portion 2 on the roller shaft 1. Are equivalent.

  FIG. 7 shows a state in which each mold member is opened and the roller shaft 1 is inserted, and then the first to third mold members 7, 8, 9 are closed and the molding material is injected from the injection port 10. It corresponds to.

  FIG. 8 corresponds to a state where the mold is opened thereafter. In FIG. 8, the first mold member 7 and the third mold member 9 are moved rightward in the drawing along the axial direction of the roller shaft 1 by the moving stage 101 of the molding apparatus 100. Of the upper and lower divided second mold members 8, the upper half including the injection port 10 is removed. By forming the mold open state as shown in FIG. 8, the roller member 12 in which the roller portion 2 is integrally formed at a predetermined portion on the roller shaft 1 can be carried out from the molding apparatus 100 upward. This carry-out operation may be performed manually by an operator or may be performed using a robot hand or the like.

  Further, in the configuration of the mold and the molding apparatus 100 shown in FIGS. 7 and 8, the position of the first mold member 7 and the third mold member 9 is moved by the moving stage 101 with respect to the roller shaft 1. It can be arbitrarily controlled by sliding in the axial direction of the shaft 1. Therefore, by adjusting the sliding amount by the moving stage 101, the pushing amount of the second mold member 8 and the third mold member 9 with respect to the flange portions 4, 4 (or the biting portions 5, 5) can be freely set. Can be set. According to the above configuration, the first mold member 7 and the third mold member at the time of mold closing by the moving stage 101 even when, for example, leakage or burr occurs around the roller portion 2. This can be accommodated by adjusting the position of 9.

  As described above, according to this embodiment, it is possible to manufacture the roller member (12) in which the roller portion (2) is integrally formed on the roller shaft (1) without requiring the conventional press-fitting process of the roller portion. it can. For this reason, the roller part is not affected by dimensional errors and work accuracy unlike post-fitting and press-fitting methods, and unnecessary force is not applied to the outer diameter of the roller. The accuracy can be maintained. Further, the roller shaft (1) and the roller portion (2) can be coupled with high strength, and the object such as a sheet material can be conveyed with high accuracy without causing any slippage or deformation of the roller portion during operation after mounting. be able to.

  Further, the roller shaft (1) used in this embodiment has first and second flange portions (4, 4) at portions corresponding to the first and second plane portions (3, 3) of the roller portion (2), respectively. 4). When the roller shaft is inserted into the mold and closed, the first and second flange portions (4, 4) are brought into contact with the second and third mold surfaces (mold members 8, 9), respectively. Alternatively, each mold surface is pushed in to the extent that a part of the flange portion is deformed halfway. Such a contact between the second flange portions (4, 4) and the second and third mold surfaces (mold members 8, 9), or a pressed state, is the shape of each mold member as described above. , Depending on the dimensions and by controlling the mold position of the molding apparatus for mounting the mold member. In particular, as described with reference to FIGS. 7 and 8, the abutting or pushing state can be finely adjusted by a molding apparatus.

  In the state where the second flange portions (4, 4) and the second and third mold surfaces (mold members 8, 9) are in contact with each other or pushed in as described above, the molding material is formed into the mold cavity (gap). The roller part is integrally formed on the roller shaft. For this reason, in this embodiment, the gap at the boundary between the roller portion (2) and the roller shaft (1) is completely shielded during casting. Therefore, the filled molding material does not leak from this boundary portion to unnecessary portions on the roller shaft or remain as burrs, and there is no resin leakage or burrs by only integral molding without requiring post-processing. A roller member (12) can be obtained.

  Further, according to this embodiment, the roller member (12) is a part of the flange portion (4, 4) of the roller shaft (1) at the respective flat surface portions (3, 3) of the roller portion (2). It is manufactured in a state where it is bitten. For this reason, for example, the thickness in the diameter direction of the roller part (2) in the flat part (3, 3) is reduced by the flange part, and the repulsive force against compression is increased. For this reason, in applications where the roller member (12) is pressed against the object by the urging member in conveying the sheet material or the like, the grip force in the vicinity of the flat portions (3, 3) at both ends of the roller portion (2) is increased. As a result, there is an effect that poor conveyance hardly occurs.

  Hereinafter, with reference to FIGS. 9 to 12, a second embodiment relating to a roller member mold, a roller shaft, or an integral molding method for manufacturing a roller member in the present invention will be described. 9, FIG. 10, FIG. 11 and FIG. 12 correspond to FIG. 1, FIG. 4, FIG. 5 and FIG. As for the molding apparatus (roller member manufacturing apparatus), the configuration shown in FIGS. 7 and 8 can be used in this embodiment. In the present embodiment, the appearance of the finally produced roller member (12) is the same as that shown in FIG. Hereinafter, the same reference numerals are used for members that are the same as or correspond to those in the first embodiment, and the detailed description thereof will be omitted.

  FIG. 9 shows a cross-sectional structure of the roller member 12 manufactured in the present embodiment. As shown in the figure, in this roller member 12, recesses 13 and 13 having stepped shapes recessed in the thickness direction of the flange portions are formed on the outer surfaces of the flange portions 4 and 4. The recess 13 having the step shape is not formed at the time of injection molding of the roller shaft 1 but is formed by press-contacting a mold. For example, the recess 13 having a step shape is formed by the second and third mold surfaces (described below) defining the first and second flat portions 3 and 3 of the roller portion 2 as shown in FIGS. The second mold member 8 and the third mold member 9) are formed by a pressure contact force when the mold is closed (clamped).

  The recesses 13 and 13 having a step shape remain as contact marks of the second mold member 8 and the third mold member 9 at the base portions of the flat portions 3 and 3 of the roller portion 2.

  FIG. 10 shows a configuration example of the roller molding die of the present embodiment in the form of a sectional view. The state of FIG. 10 is a state in which the mold is opened and the roller shaft 1 is inserted (inserted or placed) into the mold. As is clear from a comparison between FIG. 10 and FIG. 4, the overall configuration and arrangement of the mold are the same as those of FIG. The structure of the roller shaft 1 is the same as that of the first embodiment, and the shapes of the flange portions 4 and 4 are substantially the same as those in FIG.

  In the configuration of FIG. 4, the portions corresponding to the first and second plane portions 3 and 3 of the roller portion 2 of the second mold member 8 and the third mold member 9 are the flange portion 4 and the flange portion 4 when the mold is closed. It was a size and a shape of each contact | abutting to the upper part of 4 (FIG. 5).

  On the other hand, in the configuration of FIG. 10, the second mold member 8 and the second mold member 8 define the first and second plane portions 3 and 3 of the roller portion 2 of the third mold member 9. Each of the mold surfaces protrudes larger in the inner direction of the cavity (gap) than that in FIG. The second and third mold members 8 and 9 are closed (clamped) and brought into contact with the flange portions 4 and 4 so that the flange portions 4 and 4 have the above-described step shape. Recesses 13 are formed. That is, the flange portions 4, 4 are formed along the square shape of the mold surface portions 13 a, 13 a that are pressed against the upper portions of the flange portions 4, 4 of the second mold member 8 and the third mold member 9. A part is deform | transformed and the recessed parts 13 and 13 which have a level | step difference shape are formed.

  FIG. 11 shows a state before the mold of FIG. 10 is closed and the molding material is injected. At this stage, when the mold having the shape as described above is closed, the second mold member 8 and the second mold member 8 and the second mold member 8 are elastically (or plastically) deformed so that the biting portions 5 and 5 of the flange portions 4 and 4 of the roller shaft 1 are deformed. The mold surface portions 13a and 13a (FIG. 10) of the third mold member 9 are contacted and compressed. Thereby, the recessed parts 13 and 13 which have a level | step difference shape are formed in the outer side of the upper part of the flange parts 4 and 4 like illustration. The shapes of the recesses 13 and 13 are defined by the shapes of the second mold member 8 and the third mold member 9, or further, the pressure contact force of the moving stage 101 (FIGS. 7 and 8) of the molding apparatus 100. The amount of deformation of the recesses 13 can also be adjusted.

  FIG. 12 corresponds to FIG. 6 of Example 1 and shows a state in which a molding material is injected. At this stage, as described above, the flange parts 4 and 4 are elastically (or plastically) deformed, and the second mold member 8 and the third mold member 8 are in a closed state (clamped) to the extent that the recesses 13 and 13 are formed. The mold member 9 is pressed against the roller shaft 1. For this reason, the second mold member 8 and the third mold member 9 are in close contact with the biting portions 5 and 5, and the gaps at the boundary portions 11 and 11 are completely shielded. Therefore, even if the molding material is injected from the injection port 10 in this state, the molding material filled from the boundary portions 11 and 11 does not leak or flash, and the roller member has the same or better quality as that of the first embodiment. 12 can be obtained.

  Hereinafter, with reference to FIGS. 13 to 16, a third embodiment relating to a roller member mold, a roller shaft, or an integral molding method for manufacturing a roller member in the present invention will be described. In the present embodiment, similar to the second embodiment, the concave portions (14, 14) are formed in the flange portions 4, 4 of the roller shaft 1 by the shapes of the second mold member 8 and the third mold member 9, or the pressure contact force thereof. ). The difference from the second embodiment is the shape of the recesses (14, 14) formed in the flange portions 4, 4 of the roller shaft 1, and the other roller member molds and roller shafts shown in FIGS. Alternatively, the whole integral molding method is the same as that shown in FIGS. In the following description, the same reference numerals are used for members that are the same as or correspond to those in the first and second embodiments, and detailed description thereof is omitted.

  FIG. 13 shows a cross-sectional structure of the roller member 12 manufactured in the present embodiment. As shown in the figure, in the roller member 12, tapered recesses 14 and 14 that are recessed in the thickness direction of the flange portion are formed on the outer surfaces of the flange portions 4 and 4. The tapered recesses 14 and 14 are not formed at the time of injection molding of the roller shaft 1 but are formed by pressure contact with a mold. As shown in FIGS. 14 to 16, the recesses 14 and 14 are formed by the same technique as in the second embodiment. That is, also in the present embodiment, the concave portions 14 and 14 of the flange portions 4 and 4 are formed in the shape of the second mold member 8 and the third mold member 9 as in the second embodiment, or further, the molding apparatus 100. It is formed using the pressure contact force of the moving stage 101. The difference from the second embodiment is only the shapes of the recesses 14 and 14 and the shapes of the second mold member 8 and the third mold member 9 corresponding thereto.

  The concave portions 14 and 14 having the tapered shape of the present embodiment are the second and third mold surfaces that define the first and second plane portions 3 and 3 of the roller portion 2 as shown in FIGS. It is formed by the pressure contact force at the time of mold closing (clamping) of the following (second mold member 8 and third mold member 9).

  However, in this embodiment, as shown in FIG. 14, the second die member 8 and the third die member 9 correspond to the lower portions of the first and second plane portions 3 and 3 of the roller portion 2 of the third die member 9. The mold surface portions 14a and 14a are formed in a tapered shape.

  For this reason, when the respective molds are closed (clamped) as shown in FIG. 15, the mold surface portions 14a and 14a (FIG. 14) of the second mold member 8 and the third mold member 9 provide flanges. Concave portions 14 and 14 having a tapered shape are formed on the outer sides of the upper portions of the portions 4 and 4 respectively. That is, when the respective molds are closed (clamped) as shown in FIG. 15, the second mold member 8 and the third mold member with respect to the biting portions 5 and 5 of the flange portions 4 and 4 of the roller shaft 1. Nine mold surface portions 14a and 14a (FIG. 14) are pressed to form tapered concave portions 14 and 14, respectively. The shapes of the recesses 14 and 14 are defined by the shapes of the second mold member 8 and the third mold member 9, or further, the pressure contact force of the moving stage 101 (FIGS. 7 and 8) of the molding apparatus 100. The amount of deformation of the recesses 14 and 14 can also be adjusted.

  The concave portions 14 and 14 having a tapered shape remain as contact marks of the second die member 8 and the third die member 9 at the base portions of the flat portions 3 and 3 of the roller portion 2.

  FIG. 16 corresponds to FIG. 6 of the first embodiment (or FIG. 12 of the second embodiment), and shows a state in which a molding material is injected. At this stage, as described above, the flange parts 4 and 4 are elastically (or plastically) deformed, and the second mold member 8 and the third mold member 8 are in a closed state (clamped) to the extent that the recesses 14 and 14 are formed. The mold member 9 is pressed against the roller shaft 1. For this reason, the second mold member 8 and the third mold member 9 are in close contact with the biting portions 5 and 5, and the gaps at the boundary portions 11 and 11 are completely shielded. Therefore, even if the molding material is injected from the injection port 10 in this state, the molding material filled from the boundary portions 11 and 11 does not leak or flash, and the roller member has the same or better quality as that of the first embodiment. 12 can be obtained.

  In this embodiment, since the die surface portions 14a and 14a (FIG. 14) or the concave portions 14 and 14 are tapered without corners, the cross-sectional areas of the flange portions 4 and 4 can be increased. For example, it is possible to prevent the flange portions 4 and 4 from cracking or chipping when the mold is closed.

  Hereinafter, some specific examples of integral molding of the roller member will be described with reference to specific numerical values.

(Specific example of integral molding of roller member (1))
Here, a specific example in which the roller member 12 shown in FIGS. 1 to 3 described in the first embodiment is formed by the roller member mold or the manufacturing method shown in FIGS. 4 to 8 will be described.

  The shape, mold and molding conditions of the roller member 12 are as follows. For example, the roller shaft 1 of the roller member 12 has a diameter of about 6 mm and a length of about 70 mm. Moreover, the diameter of the integral molding part which integrally molds the roller part 2 shall be about (PHI) 10mm. The roller portion 2 to be integrally formed has an outer diameter of Φ14 mm, an inner diameter of Φ10 mm, a wall thickness of 2 mm, and a length of about 10 mm, and one roller portion is integrally formed with respect to one roller shaft. Further, flanges having a width of 0.4 mm and an outer diameter of Φ10.6 mm at positions substantially corresponding to both sides of the pedestal portion (integral molding portion) of the roller shaft 1 for integrally molding the roller portion 2 and the flat portions 3 and 3 of the roller portion 2. The part was formed in two places (height is approximately 0.3 mm). The roller shaft 1 as described above is manufactured by injection molding or the like separately from integral molding using another mold as described above.

  Here, not only the second mold member and the third mold member are brought into contact with the flange portions 4, 4 provided on the roller shaft 1 by the moving stage 101 of the molding apparatus 100, but also the flange portion 4. A pressure contact force that causes elastic (or plastic) deformation of 4 was applied. For example, the moving stage 101 of the molding apparatus 100 sets the second mold member and the third mold member so that the pressing amounts of the roller shaft 1 in the axial direction are about 0.02 mm, respectively, and are brought into close contact with each other. .

  The material of the roller shaft 1 is, for example, PET resin (for example, Rynite (trade name)), and is molded in advance with another mold. The material of the roller portion 2 is, for example, a styrene elastomer resin (for example, Actimer (trade name)) having a JIS hardness of about 60 °.

  Each part of the mold has a schematic configuration as shown in FIGS. 4 to 6 and a single-point gate from the injection port 10 and a cold runner system. The molding conditions set in the molding apparatus 100 were a resin temperature setting of 200 ° C., a mold cooling medium temperature of about 30 ° C., and molding was performed at a holding pressure of 60 MPa. In this example, the molding cycle of the roller part 2 was about 40 seconds.

  In the roller member 12 manufactured under the above conditions, the coaxial accuracy of the roller shaft 1 and the roller portion 2 is 0.05 mm or less, the outer diameter accuracy of the roller portion is ± 0.1 mm or less, and the axial positional accuracy of the roller portion is ± 0.05 mm. It was as good as below, and stable molding was possible without any resin leakage or burrs.

  Furthermore, when the roller member 12 manufactured under the above conditions is used as a roller member for transporting a sheet material or the like by applying a pressing force, as described above, the grip force in the vicinity of the flat portions 3 and 3 at both ends of the roller portion 2 is used. The characteristic that becomes stronger is obtained. This is considered because the repulsive force of the elastic material of the roller part 2 becomes larger than the other part because of the flange parts 4 and 4. As a result, for example, the frictional force value was improved from 1.5 to 2.0 as compared with a configuration in which the structures of the flange portions 4 and 4 were not used, and the conveyance performance of the sheet material or the like could be greatly improved.

(Specific example of integral molding of roller member (2))
Here, a specific example in which the roller member 12 of FIG. 9 described in the second embodiment is formed by the roller member mold or manufacturing method shown in FIGS. 10 to 12 will be described.

  The shape, mold, molding conditions, and the like of the roller member 12 are the same as those in the above specific example (1), and are as follows. For example, the roller shaft 1 has a diameter of about 6 mm and a length of about 70 mm. Moreover, the diameter of the integral molding part which integrally molds the roller part 2 shall be about (PHI) 10mm. The roller part 2 to be integrally formed has an outer diameter of Φ14 mm, an inner diameter of Φ10 mm, a wall thickness of 2 mm, and a length of about 10 mm, and one roller part is integrally formed with one roller shaft. Further, flanges having a width of 0.4 mm and an outer diameter of Φ10.6 mm at positions substantially corresponding to both sides of the pedestal portion (integral molding portion) of the roller shaft 1 for integrally molding the roller portion 2 and the flat portions 3 and 3 of the roller portion 2. The part was formed in two places (height is approximately 0.3 mm). The roller shaft 1 as described above is manufactured by injection molding or the like separately from integral molding using another mold as described above.

  Compared to the case of the first embodiment, in the configuration of the second embodiment, the second mold member 8 and the third mold member 9 are more actively pressed to form the square shapes of the mold surface portions 13a and 13a. The flange parts 4 and 4 are elastically (or plastically) deformed along For this reason, the pushing amount of the second mold member 8 and the third mold member 9 in the axial direction of the roller shaft 1 is set larger than that of the above specific example (1). For example, the moving stage 101 of the molding apparatus 100 sets the second mold member 8 and the third mold member 9 so that the pressing amounts of the roller shaft 1 in the axial direction are about 0.05 mm, respectively. I let you.

  The material of each part is the same as that of the specific example (1). That is, the material of the roller shaft 1 is, for example, PET resin (for example, Rynite (trade name)), and is molded in advance by another mold. The material of the roller portion 2 is, for example, a styrene elastomer resin (for example, Actimer (trade name)) having a JIS hardness of about 60 °.

  Each part of the mold has a schematic configuration as shown in FIGS. 10 to 12, and is a one-point gate and cold runner system from the inlet 10. The molding conditions set in the molding apparatus 100 were a resin temperature setting of 200 ° C., a mold cooling medium temperature of about 30 ° C., and molding was performed at a holding pressure of 60 MPa. In this example, the molding cycle of the roller part 2 was about 40 seconds.

  In the roller member 12 manufactured under the above conditions, the coaxial accuracy of the roller shaft 1 and the roller portion 2 is 0.05 mm or less, the outer diameter accuracy of the roller portion is ± 0.1 mm or less, and the axial positional accuracy of the roller portion is ± 0.05 mm. It was as good as below, and stable molding was possible without any resin leakage or burrs.

  Furthermore, at the time of casting under the above conditions, the stepped recesses 13 and 13 are formed to a depth of about 0.03 mm in the flange portions 4 and 4 exposed at the lower portions of the flat portions 3 and 3 of the roller portion 2. The second mold member 8 and the third mold member 9 are pressed against each other. As a result, resin leakage during molding could be prevented more completely and stably.

(Specific example of integral molding of roller member (3))
Here, a specific example in which the roller member 12 of FIG. 13 described in the third embodiment is formed by the roller member mold or the manufacturing method shown in FIGS. 14 to 16 will be described.

  The shape, mold, molding conditions, and the like of the roller member 12 are the same as those of the above specific example (1) and specific example (2), and are as follows. For example, the roller shaft 1 has a diameter of about 6 mm and a length of about 70 mm. Moreover, the diameter of the integral molding part which integrally molds the roller part 2 shall be about (PHI) 10mm. The roller part 2 to be integrally formed has an outer diameter of Φ14 mm, an inner diameter of Φ10 mm, a wall thickness of 2 mm, and a length of about 10 mm, and one roller part is integrally formed with one roller shaft. Further, flanges having a width of 0.4 mm and an outer diameter of Φ10.6 mm at positions substantially corresponding to both sides of the pedestal portion (integral molding portion) of the roller shaft 1 for integrally molding the roller portion 2 and the flat portions 3 and 3 of the roller portion 2. The part was formed in two places (height is approximately 0.3 mm). The roller shaft 1 as described above is manufactured by injection molding or the like separately from integral molding using another mold as described above.

  In the configuration of the third embodiment, similarly to the second embodiment, the second mold member 8 and the third mold member 9 are positively pressed to follow the inclined tapered shape of the mold surface portions 14a and 14a. The flange portions 4 and 4 are elastically (or plastically) deformed. For this reason, the pushing amount of the second mold member 8 and the third mold member 9 in the axial direction of the roller shaft 1 is set to be larger than those in the above specific examples (1) and (2). For example, the moving stage 101 of the molding apparatus 100 sets the second mold member 8 and the third mold member 9 so that the pressing amounts in the axial direction of the roller shaft 1 are about 0.1 mm, respectively. I let you.

  The material of each part is equivalent to the above specific examples (1) and (2). That is, the material of the roller shaft 1 is, for example, PET resin (for example, Rynite (trade name)), and is molded in advance by another mold. The material of the roller portion 2 is, for example, a styrene elastomer resin (for example, Actimer (trade name)) having a JIS hardness of about 60 °.

  Each part of the mold has a schematic configuration as shown in FIGS. 14 to 16 and is a one-point gate from the injection port 10 and a cold runner system. The molding conditions set in the molding apparatus 100 were a resin temperature setting of 200 ° C., a mold cooling medium temperature of about 30 ° C., and molding was performed at a holding pressure of 60 MPa. In this example, the molding cycle of the roller part 2 was about 40 seconds.

  In the roller member 12 manufactured under the above conditions, the coaxial accuracy of the roller shaft 1 and the roller portion 2 is 0.05 mm or less, the outer diameter accuracy of the roller portion is ± 0.1 mm or less, and the axial positional accuracy of the roller portion is ± 0.05 mm. It was as good as below, and stable molding was possible without any resin leakage or burrs.

  Further, in the roller member 12 manufactured under the above conditions, the second mold member 8 and the third mold member 9 are more closely attached to the roller shaft 1, and the tapered concave portions 14 and 14 are formed. The deepest part is formed with a depth of about 0.1 mm. Since such mold clamping is performed at the time of casting, resin leakage during molding can be more completely and stably prevented. Moreover, according to the structure of Example 3, since the taper shape is employ | adopted as the recessed parts 14 and 14 (or mold surface site | parts 14a and 14a) formed in the flange parts 4 and 4, the flange parts 4 and 4 are used. There is no cracking or chipping, and a great improvement in yield can be expected.

  DESCRIPTION OF SYMBOLS 1 ... Roller shaft, 2 ... Roller part, 3 ... Plane part of roller part, 4 ... Flange part, 5 ... Biting-in part, 6 ... Meat removal part, 7 ... 1st metal mold member, 8 ... 2nd metal mold | die Member, 9 ... third mold member, 10 ... inlet, 11 ... boundary portion, 12 ... roller member, 13 ... concave portion in thickness direction of flange portion, 14 ... oblique concave portion in thickness direction of flange portion

Claims (8)

A first mold surface that defines an outer peripheral portion of the roller portion; a second mold surface that defines a first flat portion rising to the outer peripheral portion of the roller portion; and the outer peripheral portion of the roller portion A roller mold is inserted into a mold having a third mold surface defining a second flat surface portion that rises up, and the mold is closed, and a molding material is injected around the roller shaft to form the roller section. In a method for manufacturing a roller member that is integrally formed with the roller shaft,
The roller shaft provided with the first and second flange portions at the portions corresponding to the first and second plane portions, respectively, and the second and third mold surfaces on the first and second flange portions, respectively. An insert step of inserting into the mold and closing the mold so that they are in contact with each other, and
The method includes an injection step of injecting a molding material for forming the roller portion into a gap defined by the first, second and third mold surfaces of the mold and the roller shaft. A method for manufacturing a roller member.   2. The method for manufacturing a roller member according to claim 1, wherein, in the insert step, the second mold surface and the third mold surface are configured such that the roller shaft is the first, second and third molds. A method for manufacturing a roller member, comprising: a mold surface portion that deforms part of the first and second flange portions when the mold is inserted and closed on the inside of the surface.   3. The method for manufacturing a roller member according to claim 2, wherein the mold surface portions of the second mold surface and the third mold surface that deform part of the first and second flange portions are stepped. A method for producing a roller member, comprising:   3. The method of manufacturing a roller member according to claim 2, wherein the mold surface portions of the second mold surface and the third mold surface that deform part of the first and second flange portions are tapered. A method for producing a roller member, comprising:   A roller member mold comprising the first, second and third mold surfaces used in the method for producing a roller member according to any one of claims 1 to 4.   A roller shaft comprising the first and second flange portions used in the method for manufacturing a roller member according to claim 1. A first mold surface that defines an outer peripheral portion of the roller portion; a second mold surface that defines a first flat portion rising to the outer peripheral portion of the roller portion; and the outer peripheral portion of the roller portion A roller mold is inserted into a mold having a third mold surface defining a second flat surface portion that rises up, and the mold is closed, and a molding material is injected around the roller shaft to form the roller section. In the roller member formed integrally with the roller shaft,
The roller portion includes an outer peripheral portion, a first flat portion rising from the roller shaft to the outer peripheral portion, and a second flat portion rising from the roller shaft to the outer peripheral portion,
The roller shaft has flange portions for preventing the molding material from leaking outside the first and second flat portions when the roller portion is integrally molded around the roller shaft by casting. Each of the roller members is provided at a portion corresponding to the flat portion.   The roller member according to claim 7, wherein the flange portion has a contact mark that contacts the second or third mold surface of the mold.

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