JP2007092966A - Manufacture of rubber hose - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To simplify diameter contraction work of inside diameter and outside diameter when manufacturing a rubber hose whose inside diameter and outside diameter on one end side are formed as contracting diameters, and improve its quality. <P>SOLUTION: When mounting a contracted outside diameter jig 150 for contracting outside diameter on one end side of the hose, a worker pushes the contracted outside diameter jig 150 into a side of rubber hose raw material PGH by using a guide shaft part 118 as guide. Consequently, the rubber hose raw material PGH enters a contracted diameter forming fitting hole 152 of the contracted outside diameter jig 150 from its end part side, its outside diameter is contracted in the contracted diameter forming fitting hole 152, and its inside diameter is contracted in a contracted diameter forming shaft part 114. The contracted outside diameter jig 150 is fitted and mounted in a condition in which centering is performed for the rubber hose raw material PGH by the guide shaft part 118 being coaxial with the contracted diameter forming shaft part 114. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a method of manufacturing a rubber hose in which a rubber hose material before vulcanization is vulcanized and one end side is shaped to have a reduced diameter on both inner and outer diameters, and a jig set used for manufacturing such a rubber hose.

  A general rubber hose is a straight rubber hose whose inner and outer diameters are uniform. However, a rubber hose having both inner and outer diameters reduced only at the end of the hose. In such a rubber hose, various methods have been proposed in order to simplify the reduction of the inner and outer diameters (for example, Patent Document 1).

Japanese Patent No. 3661338

  In this patent document, a jig for outer diameter reduction is first attached to the one end side of a hose (a rubber hose material before vulcanization) from the outside of the hose, and then a rod-shaped mandrel is inserted into the rubber hose material.

  In such a method, it is necessary to manually support the outer diameter reduction jig together with the rubber hose material when inserting the mandrel. The rubber hose material is soft and has no soreness because it is before vulcanization, so skill is required to insert the mandrel while supporting the outer diameter reduced diameter jig together with the rubber hose material by hand. there were.

  Moreover, since the hose end is covered with an outer diameter reduction jig from the outside, the positional relationship between the mandrel tip and the rubber hose material cannot be visually recognized when the mandrel tip reaches near the hose end. Therefore, since it is necessary to continue the mandrel insertion in this state, skill is required for center alignment of the mandrel tip portion and the rubber hose material at the time of mandrel insertion. If the mandrel is inserted while the center alignment is not successful, the rubber hose material will be bent unnecessarily, which may lead to poor appearance.

  Such a problem is expected to be improved to some extent if an outer diameter-reduced jig is fitted into a rubber hose material that has been inserted into a mandrel. However, since it is necessary to fit and install the outer diameter reduced diameter jig from the outside to the rubber hose material with the mandrel existing on the inner diameter, if the center alignment at this time is insufficient, the outer diameter reduced diameter jig The outer peripheral edge of the rubber hose material rubs the outer edge of the rubber hose material and tends to leave a turn or bulge on the outer edge of the end. Such turning and swelling cause poor appearance, so careful work and skill are required for fitting the outer diameter reduced diameter jig into the rubber hose material already inserted into the mandrel.

  The present invention was made in order to solve the above-mentioned problems in manufacturing a rubber hose whose one end side is shaped to have a reduced diameter on both the inner and outer diameters, and simplifies work and improves quality when reducing the inner and outer diameters. The purpose is to achieve both.

  In order to solve at least a part of such problems, in the present invention, when forming one end side of the rubber hose so that the inner and outer diameters are both reduced in diameter, a rod-shaped mandrel is inserted into the rubber hose material before vulcanization, The diameter-shaping shaft part for the hose inner diameter reduction shaping that is smaller in diameter than the inner diameter of the rubber hose material is positioned on one end side of the rubber hose material, and this diameter-shaping shaft part is made of rubber hose material. cover. The mandrel is provided with a guide shaft portion that is coaxially projected from the reduced diameter shaped shaft portion and formed with an outer diameter equal to or smaller than the outer diameter of the reduced diameter shaped shaft portion. Therefore, in the state after the mandrel is inserted, the guide shaft portion also protrudes from the rubber hose material in a state where the center is aligned with the rubber hose material covering the reduced diameter shaped shaft portion.

  In the present invention, after the mandrel is inserted as described above, an outer diameter reduced diameter jig is fitted and attached to the outside of the rubber hose material from one end side of the rubber hose material on the side covering the reduced diameter shaping shaft portion. In the present invention, the outer diameter reduced diameter jig to be fitted and mounted in this way is provided with a reduced diameter shaped fitting hole for hose outer diameter reduced diameter shaping formed with a smaller diameter than the outer diameter of the rubber hose material, and a guide shaft portion. The guide hole to enter is provided coaxially.

  Therefore, when fitting the outer diameter reduced diameter jig from one end side of the rubber hose material, in the state before the one end side of the rubber hose material enters the opening end of the reduced diameter shaping fitting hole of the outer diameter reduced diameter jig, As described above, the guide shaft portion that protrudes from the rubber hose material with the center aligned enters the guide hole of the outer diameter reduction jig. Then, the outer diameter reduced diameter jig is guided by the guide shaft portion and fitted into the outer side of the rubber hose material. For this reason, the outer diameter reduced diameter jig can be fitted and attached to the outside of the rubber hose material with the center aligned with the rubber hose material. Can be avoided. As a result, the outer diameter of one end of the rubber hose material can be reduced by the diameter-reducing shaped fitting hole without causing turning or swelling to the outer edge of the rubber hose end, so that the mandrel has already been inserted and the outer diameter is reduced. The quality of a rubber hose with a reduced diameter obtained by vulcanizing a rubber hose material that has been fitted with a jig is improved.

  In addition, the rubber hose material outer diameter is reduced by following the inner diameter of the reduced diameter shaped fitting hole by inserting the rubber hose material into the reduced diameter shaped fitting hole after fitting the outer diameter reduced diameter jig on the outer side of the rubber hose material. The inner diameter of the rubber hose material is also reduced by this outer diameter reduction. Then, the inner diameter of the rubber hose material follows the outer diameter of the reduced diameter shaping shaft portion, whereby the reduced diameter of the inner diameter of the rubber hose material is defined.

  In addition, the guide function by the guide shaft part that has entered the guide hole of the outer diameter reduction jig increases the reproducibility of the fitting work of the outer diameter reduction jig from one end of the rubber hose material. It is not necessary and simple. In addition, the guide shaft part remains in the guide hole even after the outer diameter reduced diameter jig is fitted, so that the outer diameter is reduced when the rubber hose material is carried into and out of the vulcanizer and during the vulcanization period. The diameter jig will not fall off. Accordingly, it is possible to avoid problems caused by dropping of the outer diameter reduced diameter jig, for example, reduced diameter shaping due to jig falling off when the vulcanizer is carried in or during the vulcanization period.

  In addition, since the mandrel has only to be inserted into the rubber hose material in a state where the outer diameter reduction jig is not attached, the positional relationship between the mandrel and the rubber hose material can be always grasped in the course of this insertion operation. Therefore, even if the guide shaft part or diameter-shaping shaped shaft part, which is the mandrel tip part, reaches near the end of the rubber hose material, the positional relationship between the mandrel tip part and the rubber hose material can be visually confirmed. Centering of the part and the rubber hose material becomes easy, and the bending of the unnecessary rubber hose material, and thus the appearance failure as a rubber hose can be suppressed.

  In the present invention having the above-described configuration, the mandrel used at the time of manufacturing the rubber hose has an engagement shaft portion for defining the positional relationship of the outer diameter reduced diameter jig between the reduced diameter shaping shaft portion and the guide shaft portion. The outer diameter reduced diameter jig may be provided with an engagement portion that engages with the engagement shaft portion and positions the outer diameter reduced diameter jig with respect to the mandrel. On this basis, when the reduced diameter shaped shaft portion of the mandrel is covered with the rubber hose material, the guide shaft portion protrudes from the rubber hose material while the engagement shaft portion is positioned inside the rubber hose material. The mandrel is inserted into the rubber hose material until the protruding guide shaft portion can enter the guide hole of the outer diameter reduction jig and perform the guiding function. When the one end side of the rubber hose material is positioned in the reduced diameter shaping fitting hole of the outer diameter reduced diameter jig, the guide is kept until the engaging portion engages with the engaging shaft portion. The outer diameter-reduced jig is mounted from one end side of the rubber hose material while being guided by the shaft portion.

  In this way, in order to position one end side of the rubber hose material in the diameter-reducing fitting hole of the outer diameter-reducing jig, first, the outer diameter-reducing jig is fitted and installed after receiving guidance from the guide shaft portion. The rubber hose material is inserted into the reduced diameter shaping fitting hole on one end side. After that, during the mounting of the outer diameter reduced diameter jig until the engaging portion of the outer diameter reduced diameter jig engages with the engagement shaft portion of the mandrel, the rubber hose material that remains in the reduced diameter shaping fitting hole The mandrel is continuously inserted into the rubber hose material so as to cover the reduced diameter shaping shaft portion of the mandrel together with the outer diameter reduced diameter jig. Even during the continuous insertion of the mandrel, the outer diameter reduction jig is guided by the guide shaft portion, so that the above-described problems caused by the center shift can be avoided. The positional relationship between the rubber hose material and the mandrel entering the diameter-reducing fitting hole is determined by the engagement between the engaging portion of the outer diameter reducing jig and the engaging shaft portion of the mandrel. The relative position of the shaped shaft portion and the rubber hose material is also reproduced for each rubber hose material, which is preferable for improving the quality of the rubber hose.

  In addition, this invention is applicable also as a jig set which has a mandrel and outer diameter reduction jig used for an above-described manufacturing method.

  Examples of the present invention will be described below. FIG. 1 is a perspective view schematically showing a rubber hose GH to be manufactured with a part broken away, and FIG. 2 is a schematic perspective view showing a mandrel for manufacturing the rubber hose GH.

  As shown in FIG. 1, a rubber hose GH as a finished product is formed into a reduced diameter shaped hose portion GS that is three-dimensionally bent and has one end of the hose shaped to have a reduced diameter on both inner and outer diameters. That is, in the rubber hose GH, the inner diameter / outer diameter of the hose remaining portion GZ excluding the portion of the reduced diameter shaping hose portion GS is larger than that of the reduced diameter shaping hose portion GS. The reduced diameter shaping hose portion GS is a straight tube at the end of the hose, and the hose remaining portion GZ is bent three-dimensionally.

  As shown in FIG. 2, the mandrel 100 has a round bar shape, has a mandrel base portion 102 on one end side, and has a shaping shaft portion 110 for reducing the inner diameter of the rubber hose on the other end side. An intermediate shaft portion 104 having a uniform outer diameter is formed between 102 and the shaped shaft portion 110. The intermediate shaft portion 104 has the same three-dimensional bent shape as the completed rubber hose GH shown in FIG. 1, and its outer diameter is substantially the same as the inner diameter of the rubber hose GH.

  The shaping shaft portion 110 is connected to one end side of the intermediate shaft portion 104 via the continuous shaft portion 112, and from the side of the continuous shaft portion 112, the reduced diameter shaping shaft portion 114, the engagement shaft portion 116, And a guide shaft portion 118. The continuous shaft portion 112 is formed so as to connect the shaft portions of the intermediate shaft portion 104 and the reduced diameter shaping shaft portion 114 so that the outer periphery thereof is gradually connected. In this embodiment, the continuous shaft portion 112 has an arc shape. The continuous shaft portion 112 may be tapered.

  The reduced diameter shaping shaft portion 114 is involved in the diameter reduction shaping of the hose inner diameter in the hose manufacturing process described later, and the outer diameter is the hose inner diameter of the hose remaining portion GZ and the rubber hose material in the finished rubber hose GH of FIG. The diameter is smaller than the inner diameter of the PGH, and is almost the same as the inner diameter of the reduced diameter shaping hose portion GS of the rubber hose GH. The engagement shaft portion 116 is connected to the reduced diameter shaping shaft portion 114 with an annular recess 117 interposed therebetween, and the annular recess 117 performs a positioning function of an outer diameter reduction jig described later. The outer diameter of the engagement shaft portion 116 is the same as that of the reduced diameter shaping shaft portion 114. The guide shaft portion 118 is formed so as to protrude coaxially from the reduced diameter shaping shaft portion 114 with the engagement shaft portion 116 interposed therebetween, and the outer diameter thereof is slightly smaller than that of the reduced diameter shaping shaft portion 114. The guide shaft portion 118 may have the same diameter as the reduced diameter shaping shaft portion 114.

  Next, a manufacturing process of the rubber hose GH will be described. FIG. 3 is a process diagram showing the procedure of the manufacturing process of the rubber hose GH. As shown in this process diagram, first, a rubber hose material PGH before vulcanization is prepared (step S100). If the rubber hose material PGH is a vulcanized rubber, for example, an ethylene / propylene copolymer rubber (EPDM), a straight cylindrical material formed by extruding a material before vulcanization of the EPDM rubber by an extrusion molding method or the like. It is cut with the same length as the length of the rubber hose GH as a finished product. FIG. 4 is an explanatory view showing the rubber hose material PGH together with the mandrel 100. As shown in the drawing, the rubber hose material PGH includes a through hole, and the diameter of the through hole is substantially the same as or slightly smaller than the inner diameter of the hose remaining portion GZ, and is larger than the inner diameter of the reduced diameter shaped hose portion GS. That is, the reduced diameter shaping shaft portion 114, the engagement shaft portion 116, and the guide shaft portion 118 of the mandrel 100 are formed so that the outer diameter is smaller than the through hole diameter of the rubber hose material PGH.

  Next, the mandrel 100 is inserted into the through hole of the rubber hose material PGH (step S110). FIG. 5 is an explanatory view showing the state of mandrel insertion step by step. As shown in the figure, the operator supports the rubber hose material PGH with both hands or a jig (not shown) (see FIG. 5A), and inserts the guide shaft portion 118 of the mandrel 100 into the material through-hole from one end of the rubber hose material PGH. The Then, the rubber hose material PGH is pushed in so as to follow the bent intermediate shaft portion 104 of the mandrel 100 while supporting the rubber hose material PGH (see FIG. 5B). The insertion of the mandrel 100 is continued until the guide shaft portion 118 of the shaping shaft portion 110 protrudes from the end side of the rubber hose material PGH. Prior to the insertion of the mandrel, an appropriate release agent is applied to the outer surface of the mandrel.

  After the mandrel is inserted in step S110, the reduced diameter shaped shaft portion 114 of the shaped shaft portion 110 in the mandrel 100 is positioned on one end side of the rubber hose material PGH, and the reduced diameter shaped shaft portion 114 is placed on the rubber hose material PGH. (See FIG. 5B). In this state, the mandrel 100 causes the guide shaft portion 118, which is coaxial with the reduced diameter shaping shaft portion 114, to protrude from the rubber hose material PGH.

  Further, the rubber hose material PGH is shaped so as to follow the outer diameter of the intermediate shaft portion 104 at a portion covering the intermediate shaft portion 104 by the mandrel insertion. In this case, the diameter of the through hole of the rubber hose material PGH is substantially the same as or slightly smaller than the inner diameter of the hose residual portion GZ, and the outer diameter of the intermediate shaft portion 104 is substantially the same as the inner diameter of the hose residual portion GZ. Even if it is expanded by the intermediate shaft portion 104, the expansion of the outer diameter accompanying the expansion of the inner diameter is only slight. On the other hand, on the shaping shaft portion 110 side, the rubber hose material PGH covers the reduced diameter shaping shaft portion 114 having a smaller diameter than the intermediate shaft portion 104 (specifically, the rubber hose inner diameter and the rubber hose material inner diameter) as described above. become.

  Next, initial mounting of an outer diameter reducing jig for inner and outer diameter shaping is performed (step S120). FIG. 6 is a schematic cross-sectional view of the outer diameter reduced diameter jig 150, and FIG. 7 is an explanatory view showing a state of initial mounting of the outer diameter reduced diameter jig 150. As shown in FIG. 6, the outer diameter reduction jig 150 is for reducing the inner and outer diameters of the reduced diameter shaping hose part GS in the finished rubber hose GH of FIG. 1 from the hose residual part GZ. The diameter-reducing shaping fitting hole 152 and the guide hole 154 are provided coaxially. The diameter-reducing fitting hole 152 is a hose insertion guide portion 153 having a tapered opening end, and the fitting hole inner diameter is smaller than the outer diameter of the hose remaining portion GZ (specifically, the outer diameter of the rubber hose material PGH). The outer diameter of the reduced diameter shaping hose portion GS is defined. Therefore, when the rubber hose material PGH is fitted into the reduced diameter shaping fitting hole 152, the outer diameter of the hose is reduced. As the hose outer diameter is reduced, the inner diameter of the rubber hose material PGH is also reduced. This inner diameter reduction is defined by the reduced diameter shaping shaft portion 114 as described later.

  The guide hole 154 has a diameter that allows the guide shaft portion 118 of the mandrel 100 to be inserted, and the guide shaft portion 118 that has entered the guide hole 154 can guide the outer diameter reduction jig 150. .

  The outer diameter reduction jig 150 includes an engagement chamber 155 on the bottom side of the reduced diameter shaping fitting hole 152, and a steel ball 156 is provided in the engagement chamber so as to freely enter and exit by a spring. The engagement chamber 155 is configured such that the engagement shaft portion 116 of the shaping shaft portion 110 enters, and the steel ball 156 enters and engages with the annular recess 117 of the engagement shaft portion 116. By such engagement, the outer diameter reduction jig 150 is positioned with respect to the mandrel 100 (specifically, the shaping shaft portion 110).

  When initially mounting the outer diameter reduced diameter jig 150, as shown in FIG. 7, the outer diameter reduced diameter jig 150 is brought close to the rubber hose material PGH from the hose insertion guide portion 153 side and protruded from the material end side. The guide shaft portion 118 of the shaped shaft portion 110 is inserted into the guide hole 154 of the outer diameter reducing jig 150. As a result, the guide shaft portion 118 has an outer diameter reduced diameter jig 150 in the axial direction, that is, along the axial direction of the reduced diameter shaping shaft portion 114 and the rubber hose material PGH of the outer portion in the drawing. Guide to the left. That is, the guide shaft portion 118 has an outer diameter reduced diameter in a state before one end side of the rubber hose material PGH enters the hose insertion guide portion 153 that is an opening end of the diameter reduction shaping hole 152 of the outer diameter reduction jig 150. The guide hole 154 of the jig 150 enters the guide hole 154 and fulfills a guide function for fitting the outer diameter reduced diameter jig to the outside of the rubber hose material PGH. Moreover, since the guide shaft portion 118 is coaxial with the reduced diameter shaping shaft portion 114, the guide shaft portion 118 is outside in a state where the center is aligned with the rubber hose material PGH covering the reduced diameter shaping shaft portion 114. The diameter-reducing jig 150 is guided.

  Following the initial mounting of the outer diameter reduced diameter jig 150, the outer diameter reduced diameter jig 150 for forming the inner diameter of the hose is mounted (step S130). FIG. 8 is an explanatory view showing the state of mounting of the outer diameter reduced diameter jig 150 for shaping step by step. As shown in FIG. 8, the operator pushes the outer diameter reduced diameter jig 150 toward the rubber hose material PGH with the guide shaft portion 118 as a guide. By this pushing, the fitting of the outer diameter reduced diameter jig 150 to the outside of the rubber hose material PGH proceeds, and the rubber hose material PGH is reduced in diameter from the end side along the hose insertion guide portion 153 of the outer diameter reduced diameter jig 150. The shaped fitting hole 152 is entered, and the end portion is fitted into the reduced diameter shaped fitting hole 152 until the end hits the bottom of the reduced diameter shaped fitting hole 152 (see FIG. 8A). The fitting mounting of the outer diameter reducing jig 150 is performed in a state where the rubber hose material PGH is centered as described above. Further, in the rubber hose material PGH, the outer diameter is reduced by following the inner diameter of the reduced diameter shaping fitting hole 152 in the outer diameter reduced diameter jig 150, and the rubber hose material is reduced by the outer diameter reduced diameter. The inner diameter of the PGH is also reduced. In this case, since the material through-hole diameter before the outer diameter reduction is larger than the reduced diameter shaping shaft portion 114 and the guide shaft portion 118, the inner diameter reduction of the rubber hose material PGH proceeds in a so-called free state.

  When the end of the rubber hose material PGH comes into contact with the bottom of the reduced diameter shaping fitting hole 152, the outer diameter reduced diameter jig 150 is further pushed (see FIG. 8B), and the rubber hose material PGH is The mandrel is moved so that the mandrel is inserted more than shown in FIG. That is, in FIG. 5, the tip of the rubber hose material PGH approaches the mandrel base 102, and mandrel insertion proceeds to the end.

  Moreover, on the side of the shaped shaft portion 110, the reduced diameter shaped shaft portion 114 enters the material through-hole with respect to the rubber hose material PGH whose inner diameter is reduced in a free state as described above. For this reason, the inner diameter of the rubber hose material PGH follows the outer diameter of the reduced diameter shaping shaft portion 114, whereby the reduced diameter of the inner diameter of the rubber hose material is defined. In the process of the outer diameter reduction by the reduced diameter shaping fitting hole 152 of the outer diameter reduced diameter jig 150 by the fitting mounting of the outer diameter reduced diameter jig 150 and the inner diameter reduction diameter by the reduced diameter shaping shaft portion 114 accompanying this. Since the outer diameter reduction jig 150 is guided by the guide shaft portion 118 and is in a state where the rubber hose material PGH and the center are aligned, the center of the reduced diameter shaping shaft portion 114 also enters the material through hole. It becomes a state. Even if the inner diameter reduction in the above-described free state proceeds so as to be smaller than the outer diameter of the reduced-diameter shaped shaft portion 114, the reduced-diameter shaped shaft with the center aligned as described above. Because of the entry of the portion 114, there is no particular trouble, and the inner diameter reduction due to the outer diameter of the reduced diameter shaping shaft portion 114 is defined.

  In this embodiment, the outer diameter reduction jig 150 integrated with the rubber hose material PGH is pushed (fitted), and the outer diameter reduction jig is inserted into the annular recess 117 in the engagement shaft portion 116 of the shaping shaft portion 110. The process was terminated when 150 steel balls 156 entered (see FIG. 8C). That is, the operator finishes fitting and mounting of the outer diameter reduced diameter jig 150 due to the moderation feeling due to the steel ball entering, and in this state, the mandrel insertion is also finished. FIG. 9 is a perspective view schematically showing the state of the rubber hose material PGH in a state where the mandrel insertion and the outer diameter reduction jig 150 are fitted and mounted.

  In the state shown in FIG. 8C or FIG. 9, the outer diameter reduced diameter jig 150 is positioned with respect to the mandrel 100, and thus the diameter-reduced shaft portion 114, by the steel ball 156 entering the annular recess 117. Will be made. That is, the positional relationship of the reduced diameter shaping fitting hole 152 with respect to the rubber hose material PGH covering the reduced diameter shaping shaft portion 114 is also determined, and the region of the rubber hose material PGH fitted in the reduced diameter shaping fitting hole 152 is shown in FIG. The reduced diameter shaped hose portion GS shown in FIG.

  When the mandrel insertion and the outer diameter reduction jig mounting are thus completed, the vehicle is placed on a cart (not shown) in the state shown in FIG. 9 and transported to a vulcanization processing apparatus, where the vulcanization processing is performed by the apparatus. Are all carried out from the apparatus (step S140). As a result, the rubber hose material PGH becomes a vulcanized rubber hose GH. In this state, the rubber hose GH is in the form as shown in FIG. Is removed (step S150), and GH is removed from the mandrel 100 (step S160). As a result, the finished rubber hose GH shown in FIG. 1 is obtained.

The embodiment described above has the following advantages.
(1) When the outer diameter reducing jig 150 having the diameter reducing fitting hole 152 for reducing the outer diameter of the hose is fitted into the rubber hose material PGH from the end side, the end of the rubber hose material PGH is attached. The outer diameter reduced diameter jig 150 is centered and guided by the reduced diameter shaping shaft portion 114 and the guide shaft portion 118 coaxial with the rubber hose material PGH. For this reason, since the outer diameter reduced diameter jig 150 can be fitted and attached to the outside of the rubber hose material PGH with the center aligned with the rubber hose material PGH, the hose insertion guide portion of the outer diameter reduced diameter jig 150 is initially fitted and fitted. Inadvertently rubbing the outer edge of the rubber hose material end portion with the peripheral wall of 153 or the reduced diameter shaping fitting hole 152 can be avoided. As a result, it is possible to reduce the outer diameter of one end side of the rubber hose material PGH in the reduced diameter shaping fitting hole 152 of the outer diameter reduced diameter jig 150 without incurring turning or swelling on the outer edge of the rubber hose end. It is possible to improve the quality of the rubber hose GH of a finished product that has been reduced in diameter and obtained through vulcanization.

(2) Since the center alignment and guidance are performed by the guide shaft portion 118 not only in the initial insertion (step S120) of the outer diameter reduction jig 150 but also in the subsequent insertion (step S130), the outer diameter reduction jig 150 Is not attached to the rubber hose material PGH. In addition, the reproducibility of guidance is high. Therefore, skill is not required for the mounting work of the outer diameter reduction jig 150, which is simple.

(3) Since the mandrel 100 may be inserted into the rubber hose material PGH before the outer diameter reduction jig 150 is fitted and mounted, the mandrel 100 and the rubber hose material PGH are always in the process of inserting the mandrel shown in FIG. Can be grasped. Therefore, even if the guide shaft portion 118 and the reduced diameter shaping shaft portion 114 which are mandrel tip portions reach the end of the rubber hose material, the positional relationship between the mandrel tip portion and the rubber hose material PGH can be visually confirmed. The center alignment of the mandrel tip portion and the rubber hose material PGH becomes easy, and the bending of the unnecessary rubber hose material PGH, and thus the appearance defect as the rubber hose GH can be suppressed.

(4) In the present embodiment, in the shaping shaft portion 110 of the mandrel 100, the engagement shaft portion 116 is provided between the reduced diameter shaping shaft portion 114 and the guide shaft portion 118, and the steel of the outer diameter reduced diameter jig 150 is provided. In cooperation with the sphere 156, the outer diameter reduced diameter jig 150 is positioned with respect to the mandrel 100 (specifically, the reduced diameter shaping shaft portion 114), and further, the rubber hose material PGH and the reduced diameter shaping fitting hole 152 are arranged. Perform positioning. As a result, the rubber hose material PGH is fitted into the reduced diameter shaping fitting hole 152 up to a predetermined position (specifically, the position where the material end portion hits the bottom of the reduced diameter shaping fitting hole 152). The mutual positional relationship among the shaping fitting hole 152, PGH, and the reduced diameter shaping shaft portion 114 can be defined with high reproducibility. For this reason, the length of the hose residual part GZ in the rubber hose GH as a finished product and the reduced diameter shaping of the inner and outer diameters are uniform, which is preferable in terms of improving the quality of the rubber hose.

(5) Since the guide shaft 118 remains in the guide hole 154 even after the outer diameter reduced diameter jig 150 is fitted and installed, the rubber hose material is taken into and out of the vulcanizer and is in the vulcanization period. Does not cause the outer diameter reduction jig 150 to drop off. Therefore, in addition to avoiding troubles caused by dropping of the outer diameter reduced diameter jig 150, for example, reduction in diameter forming due to jig falling off when the vulcanizer is carried in or during the vulcanization period, consideration for jig dropping becomes unnecessary and workability is improved. Rise.

  As mentioned above, although the Example of this invention was described, this invention is not restricted to above-described embodiment, In the range which does not deviate from the summary, it is possible to implement in various aspects.

  For example, the outer diameter reduction jig 150 is divided into a hose diameter reduction processing part having a reduction diameter shaping fitting hole 152 and a jig positioning part having a steel ball 156 and a guide hole 154, and both these parts are divided and mounted. A possible configuration can also be adopted.

FIG. 3 is a perspective view schematically showing a rubber hose GH to be manufactured with a part broken away. It is a schematic perspective view which shows the mandrel for manufacture of this rubber hose GH. It is process drawing which showed the procedure of the manufacturing process of rubber hose GH. It is explanatory drawing which represented this rubber hose material PGH with the mandrel 100. FIG. It is explanatory drawing which shows the mode of mandrel insertion later on. 3 is a schematic cross-sectional view of an outer diameter reduced diameter jig 150. FIG. It is explanatory drawing which shows the mode of the initial mounting | wearing of the outer diameter reduction jig 150. FIG. It is explanatory drawing which shows the mode of the mounting for shaping of the outer diameter reduction jig 150 later on. It is a perspective view which shows roughly the mode of the rubber hose material PGH in the state where the mandrel insertion and the fitting mounting of the outer diameter reduction jig 150 are completed.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 ... Mandrel 102 ... Mandrel base part 104 ... Intermediate shaft part 110 ... Shaped shaft part 112 ... Consecutive shaft part 114 ... Reduced diameter shaped shaft part 116 ... Engagement shaft part 117 ... Annular recess 118 ... Guide shaft part 150 ... Outer diameter reduction jig 152 ... Reduction diameter shaping fitting hole 153 ... Hose insertion guide part 154 ... Guide hole 155 ... Engagement chamber 156 ... Steel ball GH ... Rubber hose GS ... Reduction diameter shaping hose part GZ ... Hose remaining part PGH ... Rubber hose material

Claims (3)

One end side is a manufacturing method of a rubber hose shaped to have a reduced diameter with both inner and outer diameters,
A rod-shaped mandrel is inserted into the rubber hose material before vulcanization, and the reduced diameter shaping shaft portion for reducing the inner diameter of the hose formed at the end of the mandrel is smaller than the inner diameter of the rubber hose material. A step of covering the reduced diameter shaping shaft portion with the rubber hose material, positioned on one end side of the material,
From one end side of the rubber hose material on the side covering the reduced diameter shaping shaft portion, a reduced diameter shaping fitting hole for a hose outer diameter reduced diameter shaping formed smaller than the outer diameter of the rubber hose material is provided. Fitting and mounting an outer diameter reduced diameter jig on the outer side of the rubber hose material, and positioning one end side of the rubber hose material in the reduced diameter shaping fitting hole;
A step of vulcanizing the rubber hose material in a state where the mandrel has been inserted and the outer diameter reduced-diameter jig is fitted and fitted to the outside; and
The mandrel is provided with a guide shaft portion that is coaxially projected from the reduced diameter shaped shaft portion and formed with an outer diameter equal to or less than the outer diameter of the reduced diameter shaped shaft portion,
The outer diameter reduction jig has a guide hole into which the guide shaft portion enters, coaxially with the reduced diameter shaping fitting hole,
The guide shaft portion enters the guide hole of the outer diameter reduced diameter jig in a state before one end side of the rubber hose material enters the opening end of the reduced diameter shaping fitting hole of the outer diameter reduced diameter jig, A method for manufacturing a rubber hose that performs a guiding function of fitting the outer diameter reduced diameter jig to the outer side of the rubber hose material. A method for producing a rubber hose according to claim 1,
The mandrel includes an engagement shaft portion for defining the positional relationship of the outer diameter reduced diameter jig between the reduced diameter shaping shaft portion and the guide shaft portion,
The outer diameter reduction jig includes an engagement portion that engages with the engagement shaft portion and positions the outer diameter reduction jig with respect to the mandrel,
In the step of covering the reduced diameter shaped shaft portion of the mandrel with the rubber hose material, the guide shaft portion protrudes from the rubber hose material while the engagement shaft portion is positioned inside the rubber hose material, and the protrusion Inserting the mandrel into the rubber hose material until the guide shaft portion can enter the guide hole of the outer diameter reduced diameter jig and fulfill the guiding function,
In the step of positioning one end side of the rubber hose material in the reduced diameter shaping fitting hole of the outer diameter reduced diameter jig, the guide shaft portion is used until the engagement portion is engaged with the engagement shaft portion. A method for manufacturing a rubber hose, wherein the outer diameter reduced diameter jig is fitted and attached from one end side of the rubber hose material while receiving guidance. It is a jig set used when vulcanizing a rubber hose material before vulcanization and producing a rubber hose whose one end side is shaped to have a reduced diameter on both the inner and outer diameters,
A rod-shaped mandrel to be inserted into the rubber hose material, and an outer diameter reduced diameter jig to be fitted and attached to the outside of one end side of the rubber hose material into which the mandrel has been inserted,
The mandrel is
A reduced diameter shaping shaft portion for hose inner diameter reduction shaping formed on the mandrel end side with a smaller diameter than the inner diameter of the rubber hose material,
A guide shaft portion that is coaxially projected from the reduced-diameter shaped shaft portion, and is formed with an outer diameter equal to or smaller than the outer diameter of the reduced-diameter shaped shaft portion;
An engagement shaft portion formed in a continuous portion between the guide shaft portion and the reduced diameter shaping shaft portion;
The outer diameter reduction jig is
A diameter-reducing fitting hole for hose outer diameter-reducing shaping that is formed to be smaller than the outer diameter of the rubber hose material, and the rubber hose material is fitted from one end side,
A guide hole that is formed coaxially with the reduced diameter shaping fitting hole and into which the guide shaft portion enters when the rubber hose material is attached to the outside,
An engagement portion that engages with the engagement shaft portion and positions the outer diameter reduction jig relative to the mandrel;
The guide shaft portion enters the guide hole of the outer diameter reduced diameter jig in a state before one end side of the rubber hose material enters the opening end of the reduced diameter shaping fitting hole of the outer diameter reduced diameter jig. It fulfills the guiding function of mounting the outer diameter reduced diameter jig to the outside of the rubber hose material,
The mandrel has the guide shaft portion protruding from the rubber hose material while the engaging shaft portion is positioned inside the rubber hose material, and the protruding guide shaft portion is formed in the guide hole of the outer diameter reducing jig. Inserted into the rubber hose material until it can enter and fulfill the guiding function,
The outer diameter reduction jig is mounted from one end side of the rubber hose material while being guided by the guide shaft portion until the engagement portion engages with the engagement shaft portion.

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